Adenosine for paroxysmal supraventricular tachycardia: dose ranging and comparison with verapamil. Assessment in placebo-controlled, multicenter trials. The Adenosine for PSVT Study Group. Adenosine: a clinical experience and comparison with verapamil for the termination of supraventricular tachycardias. Electrophysiological mechanisms and determinants of vagal maneuvers for termination of paroxysmal supraventricular tachycardia. Adenosine versus verapamil in the treatment of supraventricular tachycardia: a randomized double-crossover trial. Treatment of atrial fibrillation and paroxysmal supraventricular tachycardia with bidisomide. The Atrial Fibrillation Investigation with Bidisomide (AFIB) Investigators. A randomized, placebo-controlled trial of propafenone in the prophylaxis of paroxysmal supraventricular tachycardia and paroxysmal atrial fibrillation. UK Propafenone PSVT Study Group. Comparison of Treatment of Supraventricular Tachycardia by Valsalva Maneuver and Carotid Sinus Massage. Adenosine cardioprotection study in clinical setting of paroxysmal supraventricular tachycardia. Propafenone versus amiodarone in field treatment of primary atrial tachydysrhythmias. Intravenous administration of diltiazem in the treatment of supraventricular tachyarrhythmias. Supraventricular Arrhythmia in Patients Having Noncardiac Surgery: Clinical Correlates and Effect on Length of Stay Intravenous amiodarone versus verapamil for acute conversion of paroxysmal atrial fibrillation to sinus rhythm. Risk of hospitalization for upper gastrointestinal tract bleeding associated with ketorolac, other nonsteroidal anti-inflammatory drugs, calcium antagonists, and other antihypertensive drugs. Cycling of inducibility of paroxysmal supraventricular tachycardia in women and its implications for timing of electrophysiologic procedures. Acute conversion of paroxysmal supraventricular tachycardia with intravenous diltiazem. IV Diltiazem Study Group. Early postoperative arrhythmias after pediatric cardiac surgery. Calcium antagonists are associated with reduced mortality after cardiac surgery: a propensity analysis. Abnormal Sonographic Endometrial Findings in Asymptomatic Postmenopausal Women: Possible Role of Antihypertensive Drugs Continued propranolol administration following coronary bypass surgery. Antiarrhythmic effects. Efficacy and safety of low-dose propranolol versus diltiazem in the prophylaxis of supraventricular tachyarrhythmia after coronary artery bypass grafting. Randomised controlled double-blind trial of the calcium channel antagonist amlodipine in the treatment of acute alcoholic hepatitis. Use of calcium antagonists and cognitive decline in old age: The Leiden 85-plus study Effectiveness of glibenclamide on myocardial ischemic ventricular arrhythmias in non-insulin-dependent diabetes mellitus.
OBJECTIVE To assess the safety and efficacy of intravenous adenosine in terminating acute episodes of paroxysmal supraventricular tachycardia .  DESIGN Two prospect i ve , double-blind , r and omized , placebo-controlled trials to evaluate dose response in patients receiving adenosine  and to compare the effects of adenosine with those of verapamil . PATIENTS A total of 359 patients with a tachycardia electrocardiographically consistent with paroxysmal supraventricular tachycardia were entered into the two protocol s. Patients subsequently found to have arrhythmias other than paroxysmal supraventricular tachycardia were excluded from the efficacy analysis . INTERVENTIONS The first protocol compared sequential intravenous bolus doses of 3 , 6 , 9 , and 12 mg of adenosine to equal volumes of saline . In the second protocol , patients received either 6 mg and , if necessary , 12 mg of adenosine or 5 mg and , if necessary , 7.5 mg of verapamil . MEASUREMENTS AND MAIN RESULTS When data are expressed in terms of cumulative response in eligible patients , intravenous adenosine terminated acute episodes of paroxysmal supraventricular tachycardia in 35.2 % , 62.3 % , 80.2 % , and 91.4 % of patients who received maximum doses of 3 , 6 , 9 , and 12 mg , respectively , in a four-dose sequence , whereas 8.9 % , 10.7 % , 14.3 % , and 16.1 % of patients responded to four sequential placebo doses ( P less than 0.0001 ) . In the second trial , cumulative response rates after 6 mg followed , if necessary , by 12 mg of adenosine were 57.4 % and 93.4 % , and after 5 mg followed , if necessary , by 7.5 mg of verapamil were 81.3 % and 91.4 % . The average time after injection to termination of tachycardia by adenosine was 30 seconds . Adenosine caused adverse effects in 36 % of patients , but they lasted less than 1 minute and were usually mild . CONCLUSIONS Adenosine in grade d doses up to 12 mg rapidly and effectively terminates acute episodes of paroxysmal supraventricular tachycardia in which the atrioventricular node is an integral part of the re-entrant circuit . The overall efficacy of adenosine is similar to that of verapamil , but its onset of action is more rapid . Adverse reactions to adenosine are common but are minor and brief The efficacy and side-effects of adenosine for treatment of supraventricular arrhythmias were compared to verapamil therapy in patients presenting to the emergency room . Clinical variables and the time interval from the initiation of treatment to the termination of the supraventricular tachycardia , as well as the time from the initial effective dose of medication to the termination of supraventricular tachycardia were compared for adenosine and verapamil . Adenosine was given to a total of 44 patients , 16 patients in the electrophysiology laboratory , and 28 patients in the emergency room for evaluation and termination of their tachycardia . In the electrophysiology laboratory , 7 patients had AV node reentry , 5 had Wolff-Parkinson-White syndrome , 2 of whom had atrial flutter and fibrillation but no bypass tract reentry , 1 had concealed bypass tract reentry , 1 had Lown-Ganong-Levine syndrome , 1 had intraatrial reentry , and 1 had an automatic atrial tachycardia . Twenty-five patients received  adenosine in the emergency room and 3 patients in the hospital for 31 episodes of supraventricular arrhythmias . In the emergency room , 11 patients had supraventricular tachycardia due to AV node reentry , 3 had Wolff-Parkinson-White syndrome , 6 had atrial flutter or intra-atrial re-entry , 2 had ventricular tachycardia , and 3 had sinus tachycardia . In the hospital , 2 patients had atrial flutter and one had sinus tachycardia . The group of 14 patients with supraventricular tachycardia due to Wolff-Parkinson-White syndrome or AV node reentry presenting in the emergency room were compared in a retrospective manner to the patients treated with st and ard verapamil therapy with respect to time from initiation of therapy to termination of supraventricular tachycardia and time from effective dose of medication to the termination of supraventricular tachycardia , as well as side-effects . There was no significant difference between the two groups with respect to clinical variables .  Adenosine converted 18 of 18 episodes of supraventricular tachycardia in 14 patients 24.6 + /- 9.6 seconds from the administration of the effective dose ( 0.104 + /- 0.024 mg/kg ) and a mean of 4.4 + /- 2.0 minutes from the initiation of therapy . Verapamil converted 29 of 32 episodes of supraventricular tachycardia in 20 patients , 10.9 + /- 7 minutes from the administration of the effective dose , and a mean of 16.8 + /- 20 minutes from the initiation of therapy using a mean of 8.4 + /- 3.4 mg of IV verapamil . ( ABSTRACT TRUNCATED AT 400 WORDS BACKGROUND The vagal maneuvers used for termination of paroxysmal supraventricular reentrant tachycardia ( PSVT ) appear to involve more complex mechanisms than we have known , and further study should be done to explore the possible mechanisms . METHODS AND RESULTS In this study , 133 patients with PSVT and 30 age- and sex-matched control subjects were included . We assessed the effects of different vagal maneuvers on termination of PSVT and compared baroreflex sensitivity and beta-adrenergic sensitivity between the patients with PSVT and control subjects . Out of 85 patients with atrioventricular reciprocating tachycardia ( AVRT ) , vagal maneuvers terminated in 45 ( 53 % ) . Of these , 28 ( 33 % ) terminated in the ante grade limb and 17 ( 20 % ) terminated in the retro grade limb . Out of 48 patients with atrioventricular nodal reentrant tachycardia ( AVNRT ) , vagal maneuvers terminated the tachycardia in the ante grade slow pathway ( 14 % ) or in the retro grade fast pathway ( 19 % ) . Baroreflex sensitivity was poorer but isoproterenol sensitivity test better in patients with AVNRT . Poorer ante grade atrioventricular node conduction properties and better vagal response determined successful ante grade termination of AVRT by vagal maneuvers . Poorer retro grade accessory pathway conduction property but better vagal response determined successful retro grade termination of AVRT . Better sympathetic and vagal response associated with poorer retro grade atrioventricular node conduction determined retro grade termination of AVNRT by the Valsalva maneuver . CONCLUSIONS Both the vagal response and conduction properties of the reentrant circuit determine the tachycardia termination by vagal maneuvers . Improved underst and ing of the interaction of autonomic and electrophysiological mechanisms in maintaining or terminating PSVT may provide important insight into the pathophysiology of these two tachycardias The safety and efficacy of verapamil and adenosine in the acute termination of supraventricular tachycardia were compared in a r and omized double-crossover trial . Of 32 eligible patients with either spontaneous or induced narrow complex tachycardia , seven ( 22 % ) patients experienced conversion to sinus rhythm with carotid sinus massage . The other 25 patients were r and omly assigned to receive either adenosine ( n = 14 ) or verapamil ( n = 11 ) . Relative drug efficacies were 100 % for adenosine versus 73 % for verapamil , p = NS . Adenosine given at less than or equal to 120 micrograms/kg caused conversion in 12 ( 86 % ) of 14 patients . The other two patients required 20 mg adenosine for conversion . After conversion the systolic blood pressure increased significantly in the adenosine group but not in the verapamil group . Reinitiation of tachycardia occurred in two ( 14 % ) of 14 patients r and omized to the adenosine group . Serious adverse hemodynamic effects were observed in one ( 9 % ) of 11 patients r and omized to verapamil . The incidence of conversion arrhythmias was similar in both treatment groups ( adenosine 57 % , verapamil 50 % , p = NS ) BACKGROUND Atrial fibrillation and paroxysmal supraventricular tachycardia are common disorders of the heart rhythm for which antiarrhythmic drug therapy is commonly prescribed . The Atrial Fibrillation Investigation with Bidisomide ( AFIB ) study was a r and omized , placebo-controlled clinical trial design ed to accomplish three goals in a single protocol : ( 1 ) to determine the efficacy of the antiarrhythmic drug bidisomide in the treatment of these two arrhythmias ; ( 2 ) to establish the appropriate dose range for bidisomide ; and ( 3 ) to detect an adverse mortality effect of bidisomide if one were present in patients with atrial fibrillation . METHODS AND RESULTS In this clinical trial , 1227 patients with atrial fibrillation and 187 with paroxysmal supraventricular tachycardia were r and omly assigned to bidisomide ( 200 , 400 , or 600 mg BID ) or placebo ; patient groups with each arrhythmia were analyzed separately . Symptomatic recurrences of atrial fibrillation and paroxysmal supraventricular tachycardia were documented with the use of transtelephonic ECG monitoring . The time to the first symptomatic arrhythmia recurrence was measured in each patient and compared among treatment groups . Among the atrial fibrillation patients , there was no significant difference in the time to first symptomatic recurrence between the placebo group and any of the three bidisomide treatment groups ; the hazard ratios ( placebo : treatment ) were 1.19 , 1.03 , and 1.14 for bidisomide 200 , 400 , and 600 mg BID , respectively . Among paroxysmal supraventricular tachycardia patients , there was a similar lack of a significant treatment effect ; the hazard ratios were 1.30 , 1.93 , and 1.59 for bidisomide 200 , 400 , and 600 mg BID , respectively . In the primary safety analysis of mortality , 3 of 493 patients taking placebo  died , compared with 9 of 488 patients taking one of the two higher doses of bidisomide ( P>.10 ) . CONCLUSIONS Bidisomide in the doses tested did not have a clinical ly important antiarrhythmic effect . The AFIB study provided a novel clinical trial design to test antiarrhythmic drugs for both safety and efficacy BACKGROUND Few antiarrhythmic agents have been shown in r and omized controlled trials to be effective and well tolerated in the prophylaxis of paroxysmal supraventricular tachycardia or paroxysmal atrial fibrillation .  Propafenone , a class IC anti-arrhythmic agent with weak beta-adrenoceptor antagonist properties , has shown promise in preliminary clinical studies . METHODS AND RESULTS A double-blind , placebo-controlled trial of the efficacy and tolerability of propafenone was undertaken in 100 patients with paroxysmal supraventricular tachycardia ( [ PSVT ] n = 52 ) or atrial fibrillation/flutter ( [ PAF ] n = 48 ) who had recorded two or more symptomatic arrhythmia recurrences by transtelephonic ECG monitoring during a 3-month drug-free observation period . Patients were r and omized into two consecutive crossover periods of propafenone ( 300 mg BID ) versus placebo followed by 300 mg TID propafenone versus placebo . Analysis was based on the time to treatment failure , defined as the interval from treatment onset to the occurrence of either ECG-documented arrhythmia or an intolerable adverse event . With a proportional-hazards model , we determined the relative risk ( 95 % confidence interval ) of treatment failure after the achievement of steady-state drug levels for placebo compared with propafenone 300 mg BID to be 6.8 ( 2.2 to 21.2 , P < .001 , n = 45 ) for PSVT and 6.0 ( 1.8 to 20.0 , P = .004 , n = 30 ) for PAF . Due to a greater incidence of adverse events on high-dose propafenone , the relative risks of receiving placebo rather than propafenone 300 TID were only 2.2 ( 0.9 to 5.3 , P = .1 , n = 34 ) for PSVT and 1.9 ( 0.7 to 4.7 , P = .2 , n = 25 ) for PAF . However , if adverse events were excluded in the high-dose comparison , relative risks for arrhythmia recurrence were 15.0 ( 2.0 to 113 , P = .009 ) for PSVT and incalculable ( no preferences for placebo , P = .0002 ) for PAF . One episode of wide-complex tachycardia was documented during propafenone therapy . CONCLUSIONS Propafenone is of value in the prophylaxis of both PSVT and PAF . A dose of 300 mg BID is effective and well tolerated . A larger dose of 300 mg TID causes more adverse effects but may be more effective in those who can tolerate it STUDY OBJECTIVE To compare the efficacy of the Valsalva maneuver with that of carotid sinus massage ( CSM ) in terminating paroxysmal supraventricular tachycardia ( SVT ) in the ED . METHODS This prospect i ve , r and omized case study was performed in the ED of a tertiary care institution . Patients were at least 10 years of age with regular narrow complex tachycardia and had an ECG diagnosis of SVT . Patients with regular narrow complex tachycardia were r and omly assigned to undergo either the Valsalva maneuver or CSM . If the tachycardia was not terminated by the method chosen by r and omization , then the alternative method of vagal maneuver was used . If the tachycardia was not converted by both methods of vagal stimulation , patients would undergo either synchronized electrical cardioversion or a pharmacologic method of conversion at the discretion of the treating physician , depending on the patient 's hemodynamic status . RESULTS One hundred forty-eight instances of SVT were studied . Sixty-two patients underwent Valsalva maneuver first with conversion in 12 ( success rate of 19.4 % ) . Eighty-six underwent CSM first with conversion in 9 ( success rate 10.5 % ) . Carotid sinus massage was used in the 50 cases of SVT in which conversion was not achieved with the Valsalva maneuver . Conversion occurred in 7 cases ( success rate 14.0 % ) . For the 77 cases of SVT in which initial CSM did not achieve conversion , conversion occurred in 13 with the Valsalva maneuver ( success rate 16.9 % ) . The Valsalva maneuver and CSM achieved conversion in a total of 41 instances of SVT ( success rate 27.7 % ) . CONCLUSION Vagal maneuvers are efficacious in terminating about one quarter of spontaneous SVT cases . There is no detectable difference in efficacy between the Valsalva maneuver and CSM . [ Lim SH , Anantharaman V , Teo WS , Goh PP , Tan ATH : Comparison of treatment of supraventricular tachycardia by Valsalva maneuver and carotid sinus massage . Ann Emerg Med January 1998;31:30 - 35 . ] PSVT attack of > 20min and frequency > 160 is well-recognized model of myocardial dysfunction . We measured 6-keto-PGF1alpha and TXB(2 ) before and after adenosine administration to assess its cardioprotective potential . A total of 64 patients were r and omly assigned as having acute episode of PSVT to adenosine or verapamil group . A bolus of 6 mg of adenosine up to the maximum dose of 12 or 5 mg of verapamil up to the maximum dose of 10 mg were given , until the sinus rhythm was restored . The levels of PGI(2 ) , TXA(2 ) and TAS were measured in three different time intervals . In adenosine group all parameters were normalized after 20min of conversion to sinus rhythm . The ratio of PGI(2)/TXA(2 ) increased after 5min of conversion to SR ( P<0.01 ) . Also , the ratio of TXA(2)/TAS was decreased for ADO ( P<0.01 ) . This is the first study to demonstrate that adenosine exerts cardioprotective effect Thirty-nine patients with paroxysmal atrial fibrillation or supraventricular tachycardia r and omly received amiodarone or propafenone intravenously at home . Fifteen patients received amiodarone and 24 received propafenone ; 87.5 % of the patients who received propafenone and 40 % of the patients who received amiodarone were converted at home to sinus rhythm ( P less than .005 ) . The median time of conversion was 10 minutes ( range 5 to 35 ) for propafenone and 60 minutes ( range 20 to 130 ) for amiodarone ( P less than 0.005 ) . When either drug failed to terminate atrial tachydysrhythmias at home , the same drug always restored sinus rhythm with subsequent oral treatment during hospitalization . No major side effects were observed after the infusion of either drug . The incidence of minor side effects was not significantly different between the two drugs . Both the drugs are efficacious and safe in the acute management of primary supraventricular tachydysrhythmias .  Propafenone showed a greater rapidity of action UNLABELLED The aim of the study was to investigate the efficacy of diltiazem bolus intravenous administration , compared to disopyramide , in the treatment of various types of paroxysmal supraventricular tachyarrhythmias . METHOD Fifty patients ( 23 males , 27 females , mean age 47.7 + /- 15.2 years ) with paroxysmal supraventricular tachyarrhythmia ( 20 with paroxysmal atrial tachycardia , 23 with paroxysmal atrial fibrillation and rapid ventricular response and 7 with atrial fluttering ) were studied . Diltiazem at a dose of 0.25 - 0.30 mg/kg BW or disopyramide at a dose of 50 mg were given bolus IV . If conversion of the arrhythmia to sinus rhythm could not be achieved with the initial drug , the alternate was given . The order of administration of the drugs was r and om , independent of the type of the arrhythmia . Before and during drug administration detailed clinical examination and frequent blood pressure ( BP ) measurements were performed . Twenty-four hour Holter monitoring was done in all patients , starting with the administration of the antiarrhythmic drug . RESULTS 1 ) Paroxysmal atrial tachycardia : diltiazem administration converted the arrhythmia to sinus rhythm in all patients while disopyramide in only 1 of 9 patients who received this drug . 2 ) Paroxysmal atrial fibrillation : disopyramide converted the arrhythmia in 5 patients without significant change in ventricular response in the others . Diltiazem did not convert the arrhythmia though it caused significant decrease in ventricular response ( < 100 bpm ) and in 1 patient an important bradycardia ( 45 bpm ) . 3 ) Atrial fluttering : disopyramide converted the arrhythmia to sinus rhythm in 1 patient without significant change in the ventricular response in the others . Diltiazem caused significant decrease in the ventricular response without conversion to sinus rhythm . During conversion to sinus rhythm an AV junctional rhythm of short duration ( < 1 min ) was noticed in 5 patients and a short pause ( < 2 sec ) with or without an initial premature contraction in the remaining 21 . Disopyramide administration was not associated with side effects .  Diltiazem administration cause small ( < 20 mm Hg ) , transient ( < 30 min ) decrease of BP without symptoms with the exception of the patient with bradycardia in whom the BP decrease was significant ( 90/60 from 160/80 mm Hg ) followed by intense symptoms which lasted for six hours . CONCLUSIONS Diltiazem administration is extremely effective in conversion of paroxysmal atrial tachycardia to sinus rhythm . In addition it retards ventricular response in patients with atrial fibrillation and fluttering . Compared to disopyramide these effects of diltiazem are more pronounced and clinical ly pertinent Supraventricular arrhythmia after noncardiac surgery is common [ 1 , 2 ] . Much of the data on the epidemiology and consequences of perioperative supraventricular arrhythmia in patients undergoing noncardiac surgery were collected before recent advances in anesthetic and monitoring techniques were made [ 3 ] . This clinical syndrome may have been influenced by such trends as the aging of the general population and the increased use of -blockers and calcium-channel blockers . To test the hypothesis that supraventricular arrhythmia remains a frequent event that is associated with major adverse outcomes after surgery , we studied a consecutive sample of 4181 patients who underwent major , nonemergency , noncardiac procedures and were in sinus rhythm at the preoperative evaluation . Our findings provide insight into the contemporary epidemiology and natural history of perioperative supraventricular arrhythmia . Methods Patients All patients 50 years of age or older who underwent major , nonemergency , noncardiac procedures at Brigham and Women 's Hospital , Boston , Massachusetts , from 18 July 1989 to 28 February 1994 were eligible for the study . Major noncardiac procedures were defined as those associated with an expected length of stay of 2 or more days . Procedures were electively scheduled or were done during inpatient admissions . The Brigham and Women 's Hospital Human Research Committee approved the enrollment and clinical data collection protocol s. Patients were included in this analysis if they were in sinus rhythm at the preoperative evaluation . Of the 4315 consecutive patients enrolled in the overall study , 4181 ( 97 % ) met this criterion and constituted the study sample for this analysis . Data Collection The data collection protocol is described elsewhere ( [ 4 ] ; Lee TH , Marcantonio ER , Mangione CM , Thomas EJ , Cook EF , Sugarbaker DJ , et al. Derivation and prospect i ve validation of a simple index for prediction of cardiac risk of major noncardiac surgery . In preparation ) . In brief , patients who provided informed consent for the full study protocol had preoperative evaluations done by study personnel , who used a structured data form . These evaluations included detailed medical histories , physical examinations , and laboratory testing . Intraoperative data were obtained from anesthesia flow sheets and surgeons ' notes . For patients who did not have this evaluation because they could not be approached or because they refused to participate in the interview portion of the study , clinical data were obtained from the structured evaluation performed by the anesthesiologist noted in the medical record . This data source was also used to obtain American Society of Anesthesiologists ( ASA ) classifications for all patients . Consenting patients agreed to postoperative sampling of creatine kinase . If total creatine kinase levels were elevated , creatine kinase-MB levels were measured immediately after surgery , at 8 p.m. on the evening of surgery , and on the next two mornings . For other enrolled patients , creatine kinase-MB testing was done according to the physician 's orders . Electrocardiography was performed in the recovery room and 1 , 3 , and 5 days after surgery if the patient remained hospitalized . Study personnel review ed charts daily for the occurrence of complications . Classification of Outcome The perioperative period was divided into two parts : the intraoperative period , which ended at the patient 's departure from the operating room , and the postoperative period . A perioperative supraventricular arrhythmia was diagnosed whenever a patient was noted by his or her physicians or by the study 's research personnel to have new onset of atrial fibrillation , atrial flutter , paroxysmal atrial tachycardia , multifocal atrial tachycardia , or regular supraventricular tachyarrhythmia without discernible P waves . For the purpose of this study , only episodes of supraventricular arrhythmia that were reported to be persistent or were treated with specific therapies were considered in the analysis . Review of records for a r and omly selected subset of 60 patients with supraventricular arrhythmia revealed that 87 % received specific treatment ( cardioversion or antiarrhythmic therapy ) . The postoperative occurrence of major cardiac events was classified by a single review er [ who was blinded to preoperative clinical data ] on the basis of postoperative clinical information , including cardiac enzyme measurements , electrocardiograms , and clinical events . Criteria for perioperative myocardial infa rct ion were 1 ) a new Q wave lasting 0.04 seconds or longer , 2 ) creatine kinase-MB levels greater than 5 % of an elevated total creatine kinase level with a typical increase and decrease in creatine kinase-MB levels , and 3 ) creatine kinase-MB levels greater than 3 % of an elevated total creatine kinase level in the setting of electrocardiographic changes consistent with ischemia [ 4 ] . Major cardiac events were myocardial infa rct ion , cardiogenic pulmonary edema , ventricular fibrillation or primary cardiac arrest , and sustained complete heart block . Intermediate cardiac events , recorded by study research personnel on the basis of record review , were congestive heart failure without pulmonary edema , myocardial ischemia with documented electrocardiographic changes , and documented ventricular tachycardia . Noncardiac events were pulmonary embolism , cerebrovascular accident , noncardiac pulmonary edema , respiratory failure requiring intubation , renal failure requiring dialysis , gastrointestinal bleeding , bacteremia , pneumonia , urinary tract infection , and wound infection . Statistical Analysis Univariate analyses of the correlation between clinical characteristics and the occurrence of perioperative supraventricular arrhythmia were performed by using a chi-square test and the Fisher exact test for categorical variables and a t-test or Wilcoxon test for continuous variables . Variables with a P value less than 0.10 were then entered into the multiple regression analysis . Stepwise logistic regression analysis was used to determine independent correlates of supraventricular arrhythmia . A two-sided P value less than 0.05 was considered statistically significant . Clinical ly relevant variables from the regression model were analyzed for potential interactions . Potentially significant interaction terms were considered in the regression models . In the analysis of the association between intraoperative events and the occurrence of supraventricular arrhythmia , only postoperative episodes of supraventricular arrhythmia were included ( n = 256 ) . A clinical ly significant hypotensive episode during surgery was defined as a decrease of one third in the original systolic blood pressure or a systolic blood pressure less than 90 mm Hg . Linear regression models were used to estimate the independent variation in length of stay attributable to supraventricular arrhythmia ; these models controlled for age , sex , preoperative clinical characteristics , ASA classification , type of procedure , and postoperative events ( major and intermediate cardiac events and noncardiac events ) . The log transformation of length of stay was used because of the non-normal distribution of this variable . The adjusted hospital days attributable to supraventricular arrhythmia were estimated from the percentage change in length of stay by using the geometric mean of length of stay from the final model . Results The patients ' mean age ( SD ) was 66 9 years . A total of 2244 patients ( 54 % ) were male , 563 ( 14 % ) were diabetic , 609 ( 15 % ) had a history of myocardial infa rct ion , 244 ( 6 % ) had congestive heart failure , and 1366 ( 33 % ) had evidence of ischemic heart disease . The types of procedures performed were orthopedic ( 35 % ) , thoracic ( 12 % ) , abdominal ( 12 % ) , abdominal aortic aneurysm ( 5 % ) , other vascular ( 16 % ) , and other general surgical ( 20 % ) procedures . A new perioperative supraventricular arrhythmia developed in 317 patients ( 7.6 % ) ( Table 1 ) . Less than 25 % of patients who had supraventricular arrhythmia had more than one episode of arrhythmia . Atrial fibrillation and supraventricular tachycardia without discernible P waves were the most frequent types of supraventricular arrhythmia and usually occurred in the postoperative period . The time of occurrence of postoperative supraventricular arrhythmia peaked during the first 3 days after surgery ( Figure 1 ) . This pattern of occurrence after surgery was similar for all types of supraventricular arrhythmia . Table 1 . Prevalence of Perioperative Supraventricular Arrhythmia  in 4181 Patients Undergoing Noncardiac Surgery *  Figure 1 . Distribution of  supraventricular arrhythmias ( SVA ) according to the time of first occurrence among the 256 patients who developed arrhythmias after surgery . Correlates of Supraventricular Arrhythmia Compared with patients who did not develop supraventricular arrhythmia , patients who developed this arrhythmia were significantly older and were more likely to be male ; to have a history of myocardial infa rct ion , congestive heart failure , diabetes , chronic lung disease , cancer , or arrhythmia ; to have evidence of clinical ly significant valvular disease ( such as systolic murmurs of grade III or higher ) on physical examination ; and to have premature atrial complexes on preoperative electrocardiography ( Table 2 ) . Table 2 . Univariate Analysis of Preoperative Correlates of Perioperative Supraventricular Arrhythmia * Preoperative use of calcium-channel blockers , digoxin , procainamide , and quinidine was more common in patients who developed supraventricular arrhythmia . Use of -blockers did not differ between the two groups . Patients with ASA classification III or IV were more likely to develop supraventricular arrhythmia . The most significant univariate correlate of supraventricular arrhythmia was the type of procedure performed . Patients who had abdominal aortic aneurysm repair or an intrathoracic , abdominal , or other vascular procedure had an increased risk for perioperative Abstract Amiodarone and verapamil are well-known antiarrhythmic drugs used for treatment of ventricular and supraventricular arrhythmias . Although verapamil is the drug of choice for control of the atrioventricular node , it has also been reported to terminate atrial fibrillation . 1–3 Amiodarone has been used extensively for drug-refractory ventricular tachycardia but seldom for termination of paroxysmal atrial fibrillation . 4–6 To our knowledge , no comparative study with amiodarone and verapamil has been reported . Because of this , we compared the efficacy of intravenous amiodarone versus verapamil for conversion of paroxysmal atrial fibrillation to sinus rhythm in a single-blind r and omized study BACKGROUND Nonsteroidal anti-inflammatory drugs ( NSAIDs ) cause substantial morbidity and mortality from upper gastrointestinal tract disease . Ketorolac tromethamine has been singled out as an NSAID with a distinct gastrotoxicity profile . Calcium channel blockers , a class of antihypertensive drugs , have also been found to increase the risk of gastrointestinal tract bleeding . METHODS We identified 1505 patients hospitalized because of upper gastrointestinal tract bleeding and /or perforation , and we r and omly sample d 20,000 controls in the source population . RESULTS The adjusted relative risk ( RR ) for upper gastrointestinal tract bleeding and /or perforation in NSAID users compared with nonusers was 4.4 ( 95 % confidence interval [ CI ] , 3.7 - 5.3 ) . The risk increased with higher daily doses . Ketorolac presented the highest risk ( RR , 24.7 ; 95 % CI , 9.6 - 63.5 ) and piroxicam ranked second ( RR , 9.5 ; 95 % CI , 6.5 - 13.8 ) . Ketorolac was 5 times more gastrotoxic than all other NSAIDs ( RR , 5.5 ; 95 % CI , 2.1 - 14.4 ) . The excess risk with  ketorolac  was observed with both oral and intramuscular administration and was already present during the first week of therapy . Among the various antihypertensive drug classes , beta-blockers were associated with the lowest relative risk ( RR , 1.0 ; 95 % CI , 0.7 - 1.4 ) , and current use of calcium channel blockers with the highest ( RR , 1.7 ; 95 % CI , 1.3 - 2.1 ) . The association with calcium channel blockers declined when adjusting for various markers of comorbidity ( RR , 1.4 ; 95 % CI , 1.1 - 1.8 ) . Past use of calcium channel blockers was also associated with an increased risk ( RR , 1.5 ; 95 % CI , 1.3 - 1.8 ) . CONCLUSIONS The excess risk of major upper gastrointestinal tract complications associated with outpatient use of ketorolac suggests an unfavorable risk-benefit assessment compared with other NSAIDs . More data are required to reduce the uncertainty about the apparent small increased risk of upper gastrointestinal tract bleeding in patients using calcium channel blockers Arrhythmias in women may be affected by phases of the menstrual cycle . This study was design ed to determine the prevalence of perimenstrual clustering of spontaneous episodes of paroxysmal supraventricular tachycardia ( SVT ) in women . It also tested the hypothesis that women with this temporal pattern of events have an altered probability of induction of paroxysmal SVT during electrophysiologic testing at higher estrogen states ( midcycle or with estrogen replacement therapy ) than at low estrogen states ( perimenstrual or without estrogen replacement ) . A structured history of the relation of spontaneous paroxysmal SVTs to phases of the menstrual cycle was obtained prospect ively among 42 women referred during a 3-year period . Patients with cyclical patterns of spontaneous tachycardias , who had had negative electrophysiologic studies at midcycle or while receiving estrogen replacement therapy  , had repeat procedures ( 1 ) when premenstrual or at the onset of menses , or ( 2 ) after stopping estrogen replacement therapy . Seventeen of 42 consecutive female patients ( 40 % ) had histories of perimenstrual clustering of arrhythmias . Six women ( 4 with normal menstrual cycles , 2 on estrogen replacement therapy )  , who qualified for paired electrophysiologic studies because of a negative initial electrophysiologic study that included provocation with isoproterenol , had inducibility into SVTs during the second study . All 6 had dual atrioventricular ( AV ) nodal pathway physiology , 4 had AV nodal reentrant tachycardia ( AVNRT ) induced , 1 had both AVNRT and reciprocating AV tachycardias , and 1 had nonsustained AVNRT and an atrial tachycardia induced . Successful ablation procedures were performed in 5 of the 6 patients . Thus , among women with a history of perimenstrual clustering of paroxysmal SVT and among those receiving estrogen replacement therapy , scheduling of elective electrophysiologic procedures at times of low estrogen levels ( premenstrual or off estrogen replacement therapy ) may facilitate the probability of a successful procedure Diltiazem has electrophysiologic effects similar to those of verapamil . Its efficacy and safety in 4 doses for treatment of induced supraventricular tachycardia ( SVT ) were examined and compared with those of placebo in 87 patients ( 25 with atrioventricular [ AV ] nodal reentry tachycardia , 60 with AV reentry associated with an accessory AV connection , and 2 with atrial tachycardia ) .  Conversion to sinus rhythm occurred in 4 of 14 patients ( 29 % ) with 0.05 mg/kg of diltiazem , 16 of 19 ( 84 % ) with 0.15 mg/kg , 13 of 13 ( 100 % ) with 0.25 mg/kg , and 14 of 17 ( 82 % ) with 0.45 mg/kg compared with 6 of 24 ( 25 % ) treated with placebo .  Conversion rates in groups receiving doses of 0.15 to 0.45 mg/kg of diltiazem were superior to that in the placebo group ( p less than 0.001 ) . Time to conversion was 3.0 + /- 2.6 minutes in responding diltiazem patients compared with 5.9 + /- 6.1 minutes in responding control patients . Diltiazem administration result ed in significant lengthening of SVT cycle length , AH interval , and AV nodal effective refractory period and block cycle length . The most frequent adverse response to diltiazem was hypotension ( 7 of 63 patients ) ; however , only 4 patients had symptoms related to hypotension . Thus , intravenous diltiazem in doses of 0.15 , 0.25 and 0.45 mg/kg is an effective and safe treatment for the acute management of SVT OBJECTIVE Early postoperative arrhythmias are a known complication of cardiac surgery ; however , little data exists specific to pediatrics . The purpose of this study was to determine the incidence and risk factors associated with the development of arrhythmias immediately after surgery in a pediatric population . METHODS Data were collected in a prospect i ve observational format from pediatric patients undergoing cardiac surgery between September 2000 and May 2003 . This format included age , anatomy , surgical repair , and serum magnesium and calcium levels , as well as cardiopulmonary bypass and aortic crossclamp times . Patients were continuously monitored , and hemodynamically significant arrhythmias were recorded . RESULTS Arrhythmias occurred in 28 of the 189 patients enrolled ( 15 % ) including 16 with junctional ectopic tachycardia , 7 with complete atrioventricular block , 4 with ventricular tachycardia , and 1 with re-entrant supraventricular tachycardia . Significant differences were found between the arrhythmia and nonarrhythmia groups with regard to age ( 22 vs 45 months ) , cardiopulmonary bypass time ( 189 vs 109 minutes ) , and aortic crossclamp time ( 105 vs 44 minutes ) ; P < .05 . Magnesium and calcium levels were not significantly different between the groups . Two repairs carried an increased risk : complete atrioventricular septal defect repair , 8 of 11 patients ( 72 % ) , and the arterial switch 5 of 8 patients ( 62.5 % ) ; P < .05 . Atrioventricular septal defects had an even higher incidence when controlled for age , bypass time , and crossclamp time ( odds ratio = 7.65 ) . CONCLUSIONS Hemodynamically significant postoperative arrhythmias are a frequent complication of pediatric cardiac surgery . Younger age and longer bypass and crossclamp times are risk factors for arrhythmia . In addition , the repair of atrioventricular septal defects carries an independent risk of arrhythmias OBJECTIVES Observational studies have question ed the effectiveness of perioperative calcium channel blockers but failed to correct for selection biases . We therefore performed a prospect i ve observational cohort study of the effects of calcium channel blockers on cardiac surgical  mortality . A propensity score technique was used for risk adjustment . METHODS We identified 6619 patients who underwent nontransplant cardiac surgery at the Toronto General Hospital ( Toronto , Ontario , Canada ) between May 1999 and December 2001 . Propensity scores for calcium channel blocker use were constructed for the entire sample and for the subgroup ( n = 5222 ) that underwent coronary artery bypass grafting . The calcium channel blocker adjusted odds ratio for in-hospital mortality after cardiac surgery was determined by using multiple logistic regression and propensity matched-pairs analyses . A subgroup analysis was performed for patients who underwent coronary artery bypass grafting :  the calcium channel blocker adjusted odds ratio for mortality was determined by using propensity score matched-pairs analyses . RESULTS Calcium channel blockers were associated with significantly reduced cardiac surgical mortality after adjustment with both multiple logistic regression ( odds ratio , 0.56 ; 95 % confidence interval , 0.33 - 0.94 ; P = .028 ) and propensity score matched-pairs analyses ( odds ratio , 0.56 ; 95 % confidence interval , 0.32 - 0.98 ; P = .042 ) . Calcium channel blockers were also associated with reduced mortality ( odds ratio , 0.48 ; 95 % confidence interval , 0.23 - 0.98 ; P = .044 ) among patients who underwent coronary artery bypass grafting . CONCLUSIONS After adjustment for baseline differences , calcium channel blockers were associated with significantly reduced mortality after cardiac surgery . This benefit also extends to the subgroup that underwent coronary artery bypass grafting . A large r and omized controlled trial of perioperative calcium channel blockers is therefore warranted OBJECTIVE The purpose of this study was to evaluate the possible effect of the antihypertensive agent nifedipine ( a calcium channel antagonist ) on the endometrium of asymptomatic menopausal women by using transvaginal sonography , hysteroscopy , and endometrial sampling . DESIGN Eighty-five asymptomatic postmenopausal women with an ultrasonographically detected endometrial thickness of more than 7 mm were examined . The study group comprised 43 women treated with nifedipine ( 30 - 60 mg/day ) for mild to moderate hypertension for at least 1 year , and the control group comprised 42 normotensive women . All participants underwent transvaginal sonography , hysteroscopy , and , if necessary , endometrial biopsy . RESULTS Of the 85 patients , 53 were found to have atrophic endometrium , 36 ( 83.7 % ) in the study group and 17 ( 40.5 % ) in the control group . The difference between the groups was statistically significant ( p < 0.05 ) . There were three cases of hyperplasia and three cases of carcinoma of the endometrium , with similar rates in the two groups . CONCLUSIONS Among asymptomatic postmenopausal patients with sonographically thickened endometrium , atrophic endometrium was found to be significantly more prevalent in those using calcium channel antagonists to control hypertension than in those who were normotensive controls . The presence of endometrial hyperplasia and malignancy in the study group underscores the importance of meticulous endometrial evaluation whenever sonographically thickened endometrium is encountered One hundred consecutive patients requiring propranolol hydrochloride before undergoing isolated aortocoronary bypass procedures were examined . In half the patients , propranolol therapy was discontinued , whereas the other half continued to receive intraoperative and postoperative propranolol regardless of clinical events . Although there were no preoperative differences in the apparent degree of coronary arterial disease or left ventricular function in the two groups , postoperative supraventricular arrhythmias were less frequent in the propranolol-treated group , most noticeably in those receiving less than 320 mg preoperatively . In patients who had received large preoperative doses ( greater than or equal to 320 mg/day ) , there were no significant differences in postoperative supraventricular tachycardias . Continued propranolol therapy following isolated coronary bypass surgery appears to be a safe and efficacious method of decreasing the incidence of postoperative supraventricular tachycardias OBJECTIVE Supraventricular tachyarrhythmias ( SVT ) complicate postoperative management after coronary bypass surgery in about 30 % of all patients . Though a prophylactic treatment both with beta-adrenergic blocking agents and the calcium antagonist diltiazem has been used for the prevention of post-operative SVT , no study yet has performed a prospect i ve comparison of the efficacy of these therapies . METHODS To investigate the prophylactic effect of either a calcium antagonist ( diltiazem , 0.1 mg/kg per h i.v . ) or a beta-adrenergic blocking agent ( propranolol , 10 mg every 6 h postoperatively ) , we r and omized prospect ively 103 consecutive patients into three groups , the third one serving as a control group . Anti-arrhythmic medication was started with the procedure and was continued until the 3rd postoperative day . RESULTS Preoperative conditions were the same for the three groups concerning age , extent of coronary heart disease , ventricular function and heart-related medication . There were no differences in intraoperative parameters or postoperative enzyme patterns . Diltiazem was ineffective in preventing SVT , the incidence being exactly the same as in the control group ( 35 % ) . Propranolol reduced the occurrence of SVT significantly ( 7 % , P < 0.05 ) . Furthermore , patients treated with diltiazem needed positive inotropic support more often in the first hours after surgery than patients of the control group ( 30 % vs 5 % , P < 0.01 ) . CONCLUSIONS The perioperative administration of low-dose propranolol is considered a safe and effective drug prophylaxis to avoid the occurrence of SVT after bypass surgery BACKGROUND / AIMS Calcium channel blockers have a hepatoprotective action in animal models of alcohol-induced liver injury but their effect in alcoholic liver disease in humans has not been previously investigated . We have conducted a r and omised , placebo-controlled trial to investigate the possible benefit of the calcium channel blocker amlodipine in terms of 4-week survival in hospitalised patients with severe acute alcoholic hepatitis . METHODS Sixty-two patients with acute alcoholic hepatitis were r and omised to receive 5 - 10 mg amlodipine each day for 1 year or an identical capsule containing placebo . In 36 ( 58 % ) , acute alcoholic hepatitis was confirmed on biopsy and in the remainder on clinical and laboratory criteria . There were no statistically significant differences in clinical characteristics and disease severity in the treated and placebo groups . RESULTS Of the 32 patients receiving amlodipine , there were six deaths ( 19 % ) in the first 4 weeks compared with seven ( 23 % ) of the placebo patients ( p=0.329 ) . Causes of death were similar in the amlodipine and control groups , with liver failure predominant . Analysis by the Cox proportional hazards model after adjustment for other prognostic factors showed survival was not significantly influenced by active treatment ( p=0.07 ) . One patient in each group was withdrawn because of the development of hypotension , but this did not recur on re introduction of the capsules . CONCLUSIONS This study shows that calcium channel blockers are well tolerated with few side effects in advanced alcoholic liver disease , but there is no conclusive evidence from this study that calcium channel blockers are helpful in the treatment of alcoholic hepatitis The systolic hypertension in Europe ( Syst-Eur ) trial has been the only trial that has suggested a protective effect of antihypertensive treatment on incidence of dementia . It is unclear whether this protective effect has been caused by the blood pressure lowering effect of the calcium antagonist nitrendipine or by the calcium channel inhibition . From the Leiden 85-plus study , a population -based cohort study of 599 subjects aged 85 years , we selected 204 subjects who used at least one antihypertensive at baseline . Associations between use of antihypertensives at baseline and change in cognitive functioning over time were assessed with linear mixed models . After adjusting for gender , education , and use of other antihypertensives , only use of calcium antagonists was associated with a significant decelerated annual cognitive decline during follow-up ( 0.40 MMSE-points per year , p=0.001 ) . Use of other antihypertensives was not associated with a decelerated annual cognitive decline ( all p values > 0.3 ) . Our data support the interpretation that the reported prevention of dementia by calcium antagonists is exerted through its calcium channel inhibition rather than its blood pressure lowering properties Glibenclamide , a hypoglycemic sulfonylurea , is a blocker of the adenosine triphosphatase-modulated potassium ion channels . The opening of these channels in the myocardial cells , induced by acute myocardial hypoxia , can be responsible for ischemic ventricular arrhythmias . To evaluate the antiarrhythmic effects of this drug 19 non-insulin-dependent diabetic patients were selected . They had coronary artery disease and evidence on Holter monitoring of ventricular premature complexes or nonsustained ventricular tachycardia , or both , induced by transient myocardial ischemia . In all patients , 24-hour electrocardiographic monitoring was performed to evaluate the number and duration of myocardial ischemic events , the frequency of ventricular premature complexes and nonsustained ventricular tachycardia per minute of ischemia and the percentage of ventricular premature complexes versus total ischemic beats . Selected patients were classified in 2 groups : group A ( 9 patients ) received metformin ( placebo ) and group B ( 10 patients ) was treated with glibenclamide . On the fourteenth day patients underwent 24-hour control monitoring . Then a crossover between the 2 groups was made and a new Holter monitoring sequence was performed at the end of the second phase . Results indicate that glibenclamide significantly ( p less than 0.001 ) reduced both the frequency of ventricular premature complexes and the episodes of nonsustained ventricular tachycardia during transient myocardial ischemia , but did not change the number and duration of acute myocardial ischemic attacks and did not reduce the spontaneous ventricular arrhythmias . Thus , glibenclamide appears to have an antiarrhythmic effect in preventing ventricular arrhythmias induced by transient myocardial ischemia
In the pooled analysis there was no significant difference in reversion rate or relapse rate between the two drugs .
Adenosine and verapamil are both effective treatments for supraventricular tachycardia in the majority of patients .
BACKGROUND Patients with paroxysmal supraventricular tachycardia frequently present to the Emergency Department .
Where vagal manoeuvres fail , the two most commonly used drugs are adenosine and calcium channel antagonists .
Both are known to be effective but both have a significant side-effect profile .
OBJECTIVES To examine the relative effects of adenosine and calcium channel antagonists and , if possible , to determine which is most appropriate for the management of supraventricular tachycardia .