bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sensitivity and specificity of programmed atrial stimulation for induction of supraventricular tachycardias
Authors: Manolis A. S. , Manolis A. S. , Deering T. , Han E. H. , Estes N. A. M. 
Published: February 2009

AbstractThe sensitivity and specificity of two programmed atrial stimulation protocols were studied in 92 consecutive patients undergoing electrophysiologic studies both with (35 patients) and without (57 patients) clinical supraventricular arrhythmias. Protocol I (P I) consisted of incremental atrial pacing to 2:1 atrioventricular (AV) block and a single atrial extrastimulus scanned by 10 ms decrements through diastole to the atrial effective refractory period at a single drive‐cycle length. Protocol II (P II) included a second atrial extrastimulus scanned by 10 ms decrements through diastole at a single drive‐cycle length with the first extrastimulus set 20 ms from the atrial effective refractory period. Rapid atrial pacing at cycle lengths of 350, 300, and 250 ms was then performed with PII. P I was employed in all patients while P II was studied in the final 48 patients only. Of the 35 patients with clinical atrial arrhythmias, 26 (74%) of their arrhythmias were induced with either P I (18/35; sensitivity = 51%) and/or P II (12/17; sensitivity = 71%). Of the 57 patients without clinical atrial arrhythmias (control group), atrial arrhythmias were induced in 11 (19%), 3 with PI (specificity 95%, 54/57) and 8 with P II (specificity 74%, 23/31). The sensitivity of P II was higher (71%), but its specificity was lower (74%) than P I (51% and 95%, respectively; p>0.05). The positive predictive value of P II was lower (60%) than that of P I (86%) (p>0.05), but the negative predictive value (82%) and predictive accuracy (73%) were comparable to those of P I (76% and 78%, respectively). In conclusion, protocol II (P II) including double extrastimuli and rapid atrial pacing can enhance sensitivity of programmed atrial stimulation in inducing atrial tachyarrhythmias, but results in lower specificity when compared to protocol I (P I).
Nisoldipine: A replacement therapy for nifedipine in the treatment of severe hypertension
Authors: Grossman E. , Rosenthal T. 
Published: February 2009

AbstractThe use of nisoldipine (10–20 mg b.i.d.) was evaluated as a replacement therapy for long‐acting nifedipine (40–120 mg/day) in 21 patients with severe hypertension, who were resistant to or intolerant of nifedipine. Except for one patient with specific contraindications, all participants received an individually determined constant dose of beta blocker throughout the 8‐month study. Results indicated a significant decrease in blood pressure after four weeks of treatment with nisoldipine (173 ± 5/98 ± 4 to 156 ± 3/91 ± 2 mmHg, p>0.05) without an associated change in pulse rate in 19 patients; only 5 of the 21 patients showed no further benefit from nisoldipine. No significant biochemical changes were noted in any of the patients during the study. In three patients, leg edema that had developed as a consequence of previous nifedipine therapy resolved completely following nisoldipine administration. Two patients withdrew from the study before term because of headaches and palpitations. An additional two patients suffered headaches, but tolerated the drug and continued the study. One patient suffered from polyuria. Nisoldipine appears to be an effective substitute treatment for nifedipine in severely hypertensive patients sensitive or resistant to nifedipine.
Study of the left ventricular function in pregnancy‐induced hypertension
Authors: Escudero E. M. , Favaloro L. E. , Moreira C. , Plastino J. A. 
Published: February 2009

AbstractLeft ventricular (LV) morphological and functional characteristics in 9 women suffering from pregnancy‐induced hypertension (PIH) were studied by means of echocardiograms. In order to distinguish which changes depended on the pressure values and which were the result of pregnancy, 10 nonpregnant control women with no heart disease and 10 normal pregnant women (NP) were studied and the results of each of the groups compared. To evaluate the structure, left ventricular systodiastolic diameters and wall thickness were measured. The only statistically significant difference was in the diastolic diameters between the PIH (4:7 ±0.3 cm) and the control group (4.4±0.2 cm) p>0.01. Left ventricular mass was significantly increased (p>0.01) in the PIH patients (185±53.1 g) compared to the NP patients (161 ±29.6 g) and the control group (125±17.4 g). No statistically significant differences were found in the radius thickness ratio in the three groups. The systolic function assessed by the shortening percentage was significantly lower (p>0.05) in the control group (32.8±4.4%) and in the NP patients (37.8±5.2%) than in the PIH group (39±6.5%). Afterload assessed by isovolumic period stress was significantly greater (p>0.01) in the PIH patients (157 ± 10.6 dyne/cm2) compared with the NP group (118.9±7.01 dyne/cm2). There were no significant differences between the first group and the control group (134.09± 8.7 dyne/cm2). As evidence of the diastolic function, analysis was made, on the one hand, of diastolic isovolumic period length (DIP). Values in the control group were 50±8.1 ms, in NP 54 ±14.2 ms, and in PIH 50±12.2 ms. There were no significant differences between the groups. On the other hand, peak velocity diameter diastolic changes were determined: that of the control group was 18±3.8 cm/s; for the NP group, 18±5.9 cm/s; and for the PIH group, 21 ±5.3 cm/s. There were no statistically significant differences here either. The foregoing results lead us to the conclusion that PIH does not produce evident structural changes in the left ventricular cavity beyond those already caused by adaptation to pregnancy. The changes in systolic function may be secondary to the effects of an added adrenergic activity, suggested in turn as being responsible for this hypertension. Diastolic function is not altered despite the increase in the left ventricular mass in this group of patients.
Abnormal pharmacokinetics of flecainide in a “Nonresponder”
Authors: Tsukamoto H. , VAN Gelder I. C. , Crijns H. J. G. M. , VAN Wijk L. M. , Lie K. I. 
Published: February 2009

AbstractFlecainide is well absorbed after oral administration. Following rapid infusion of flecainide, there is a short distribution phase. Plasma levels of flecainide are proportional to dose. Both QRS durations and flutter wave intervals are lengthened after flecainide administration. We report an abnormal pharmacokinetic response to oral as well as intravenous flecainide in a patient who was treated with flecainide for several episodes of atrial flutter. In contrast to the usual pattern, this patient did not show a significant increase in QRS duration, flutter wave interval, or plasma concentration. We could not explain this abnormal pharmacokinetic response, but excluded a rapid and complete renal clearance, an excessively high rate of metabolization, and an abnormal binding mechanism as possible mechanisms. We concluded that flecainide may produce abnormal pharmacokinetic mechanisms, preventing appearance of unbound substance in plasma, thereby preventing occurrence of electrophysiological effects.
Persistent painless st‐segment depression after exercise testing and the effect of age
Authors: Flugelman M. Y. , Halon D. A. , Shefer A. , Peer M. , Dagan T. , Lewis B. S. , Schneeweiss A. 
Published: February 2009

AbstractThe relation between the duration of ischemic ST‐segment depression (1 mm or more 60 ms after the J point) and the clinical awareness of chest pain was studied in 31 patients (aged 39–73 years) undergoing symptom‐limited, graded treadmill exercise testing. The response of these patients to nitrate therapy (spray or sublingual tablet) given immediately on cessation of exercise was also studied. During exercise, angina pectoris appeared at an estimated workload of 4.6±2.2 metabolic equivalents (METS) (mean±SD), and pathological ST‐segment depression at 4.9 ± 1.9 METS (p=NS.) On cessation of exercise, angina disappeared after 3.0±1.9 min, but ST‐segment depression persisted for more than twice as long (6.6 ± 4.1 min) (p < 0.0001). The ratio of time to ST‐segment recovery/time to relief of pain (a quantitative measure of silent ischemia during recovery) increased with age (r = 0.49, p = 0.002), and in 16 patients over 60 years of age was higher than in 15 younger patients (3.6 ± 2.5 vs. 2.1 ± 1.4) (p < 0.04). The silent ischemia ratio after exercise tended to decrease, although not significantly so (p = 0.2), in patients who received oral nitrates; there was no difference in the response to spray or tablet in this regard. We conclude that ST‐segment depression frequently persists after relief of exercise‐induced angina pectoris and more so in elderly patients.
Systemic and coronary hemodynamic effects of combined oral alpha‐ and beta‐adrenergic blockade (labetalol) in normotensive patients with stable angina pectoris and positive exercise stress tests
Authors: Feldman R. L. , Prida X. E. , Hill J. A. 
Published: February 2009

AbstractThe systemic and coronary hemodynamic effects of combined alpha‐ and beta‐adrenergic blockade produced by oral labetalol were assessed in 12 normotensive patients with angina pectoris and an ischemic electrocardiographic response to exercise stress. At rest, labetalol (200 mg, orally) produced systemic vasodilation (systemic vascular resistance ‐9%, p < .01) as aortic pressure fell and cardiac output was unchanged. Left ventricular (LV) end‐diastolic pressure also fell slightly (17%, p = .05). Systemic vasodilation was not accompanied by reflexly mediated increases in heart rate. Coronary flow and resistance and myocardial oxygen uptake were unchanged. Before labetalol, supine bicycle exercise produced angina in 10 patients. After labetalol, exercise duration was prolonged in 6 of these 10 (average 56%). During exercise, tachycardia was blunted (‐7%, p < .05) as were increases in aortic pressure (‐12 %, p < .01) and coronary sinus flow (‐25%, p = .03). Cardiac output and LV end‐diastolic pressure were similar to control period values. These hemodynamic effects of oral labetalol appeared beneficial, differed from those expected of classic beta‐adrenergic blocking agents, and were, in general, similar to those we have observed after intravenous labetalol. The clinical response was good and the drug safe. Labetalol should undergo further evaluation in normotensive as well as hypertensive patients with ischemic heart disease.
Etiology and prognostic implications of a large pericardial effusion in men
Authors: Colombo A. , Olson H. G. , Egan J. , Gardin J. M. 
Published: February 2009

AbstractTo assess the etiology and prognosis of a large pericardial effusion, we reviewed 25 consecutive patients who presented with a large pericardial effusion and underwent a drainage procedure. Large pericardial effusion was defined as: (1) an echo‐free space > 10 mm anteriorly and posteriorly by M‐mode echocardiography and (2) removal of > 350 ml of fluid at pericardial drainage. The etiologies of large pericardial effusion were: neoplastic (36%), idiopathic (32%), uremic (20%), postmyocardial infarction (8%), and acute rheumatic fever (4%). Of our patients, 44% presented with cardiac tamponade, while 25% of patients with idiopathic pericarditis had hemorrhagic effusion and cardiac tamponade. At follow‐up, 37 ± 17 months after pericardial drainage, 68% had died from complications of their underlying disease. There were no deaths attributed to pericardial disease. While 88% of patients with idiopathic large pericardial effusion were alive at follow‐up, none of the neoplastic large pericardial effusion patients survived longer than 5 months after initial pericardial drainage (p < 0.001). Additionally, the survival of patients with uremic large pericardial effusion was better than patients with neoplastic large pericardial effusion (p < 0.05). We conclude: (1) neoplastic, idiopathic, and uremic pericarditis are the most common causes of large pericardial effusion in men, (2) idiopathic pericarditis can be hemorrhagic and cause cardiac tamponade, and (3) the prognosis of large pericardial effusion is related to patients' underlying disease.
Comparison of auscultation with two‐dimensional and doppler echocardiography in patients with suspected mitral valve prolapse
Authors: Barron J. T. , Manrose D. L. , Liebson P. R. 
Published: February 2009

AbstractAuscultation was compared to two‐dimensional echocardiography (2D echo) and Doppler ultrasonography in 140 consecutive patients referred for evaluation for suspected mitral valve prolapse (MVP) to assess the precision of the two diagnostic methods. Ninety patients (64%) had midsystolic clicks, of which 42 (47%) had MVP by echocardiography; 6 patients (4%) had MVP by 2D echo but no click on examination. In 15 (17%) of the 90 patients, a click was heard only in the standing or squatting positions and 2D echo did not detect prolapse in the supine position in 10 (67%) of the 15. With auscultation as the reference standard for MVP, 2D echo has a sensitivity of 47% and a specificity of 89%. Of the 140 patients, 51 (36%) had systolic murmurs; Doppler detected mitral and/or tricuspid regurgitation in 26 (50%). In 23 (16%) patients, there was Doppler evidence of mitral or tricuspid regurgitation even though systolic murmurs were not heard. Auscultation shows a 53% sensitivity and 73% specificity for systolic murmurs, using Doppler ultrasonography as the reference standard. Of 48 patients with MVP by 2D echo, 15 (13%) had associated mitral regurgitation by Doppler. The results indicate that 2D echo and Doppler ultrasonography should be interpreted in concert with auscultation for the diagnosis of mitral valve prolapse and for therapeutic decision making.
Systolic time intervals in duchenne muscular dystrophy: evaluation of left ventricular performance
Authors: Chenard A. A. , Becane H. M. , Tertrain F. , Weiss Y. A. 
Published: February 2009

AbstractThe purpose of this study was to evaluate the prevalence of latent cardiac heart failure in Duchenne's muscular dystrophy (DMD). Systolic time intervals (STI) were measured in a cross‐sectional study of a group of 177 patients 6‐21 years old. Total electromechanical systole (QS2), left ventricular ejection time (LVET), and pre‐ejection period (PEP), were corrected for heart rate by means of regression equations obtained from 33 normal subjects (QA2 I, LVET I, PEP I). Mean STI values were significantly different from those observed in an age‐matched control group. PEP I was prolonged, LVET I was abbreviated, while QS2 I remained unaltered. STI varied significantly with age. Abnormal values were uncommon before age 10 years. The most critical period was 14–16 years, with an abrupt increase in prevalence from 35 to 72%. Such changes point to the practical use of the STI for clinical decision making especially for surgery.
Acute renal failure following low osmolality radiocontrast dye
Authors: Elliott C. , Reger M. 
Published: February 2009

AbstractIt is hoped that recently released low osmolality radiocontrast agents (RCAs) will have a lower nephrotoxic potential, since dye nephropathy may be related to hyperosmolality. We report here 2 cases of typical oliguric dye nephropathy in patients without risk factors for dye nephropathy. These cases show that these new agents do have nephrotoxic potential.
Cardiac dysfunction associated with the acquired immunodeficiency syndrome (aids)
Authors: Webb J. G. , Chan‐Yan C. , Kiess M. C. 
Published: February 2009

AbstractFive patients with acquired immune deficiency syndrome (AIDS) developed clinical evidence of mild to severe cardiac dysfunction confirmed by nuclear angiography and echocardiography. In 4 patients who were studied postmortem there was no evidence of myocarditis, valvular, or ischemic heart disease. Cardiac involvement in patients with AIDS may include pericardial and myocardial involvement by opportunistic pathogens or Kaposi's sarcoma, subclinical myocardial dysfunction, or an as‐yet unexplained cardiomyopathy.
Extraction of an intracardial catheter embolus using combined radiography and transesophageal echocardiography
Authors: Neumann H. P. H. , Hofmann T. , Koester W. , Billmann P. , Kauffmann G. W. 
Published: February 2009

AbstractEmbolism of a fragment of a central venous catheter is a serious clinical complication, especially when the fragment cannot be made visible by radiological methods. We report a case where such a fragment could only be localized by transesophageal echocardiography (TEE). With combined use of x‐rays and TEE, the catheter embolus was successfully extracted using a conventional Dormia catheter. For similar situations the described procedure is recommended.
Aspergillus endocarditis in association with a false aortic aneurysm
Authors: Corrigan C. , Horner S. M. 
Published: February 2009

AbstractA 32‐year‐old man was admitted with an intracerebral hematoma and subsequently with bilateral femoral emboli five months after aortic valve replacement. Blood cultures for bacteria and fungi were negative but microscopy of the embolus revealed Aspergillus fumigatus. At operation a large false aneurysm of the ascending aorta and vegetations on the prosthetic aortic valve were found. Aspergillus endocarditis is diagnosed antemortem in only 23% of fatal aortic aneurysms: blood cultures are positive in only 8%. Clinically a large vessel embolus is characteristic, being present in 83% and microscopy and culture of such an embolus if present are vital investigations.
Coronary artery bypass surgery in women
Authors: Becker R. C. , Corrao J. M. , Alpert J. S. 
Published: February 2009

AbstractCoronary bypass surgery is performed more frequently in men than in women. A selection bias in favor of men may exist in currently utilized evaluation precesses for patients with both chest pain syndromes and documented coronary artery disease. Surgery should be considered in women with significant left main coronary artery stenosis, “left main equivalent” coronary disease, severe three‐vessel coronary disease with/without left ventricular dysfunction, two‐vessel coronary disease (including a proximal left anterior descending artery stenosis), and unstable angina pectoris with decreased left ventricular function. Women and men undergoing coronary bypass surgery seem to benefit from internal mammary artery grafts used alone or in combination with saphenous vein grafts. Surgical mortality, incomplete revascularization, early and late graft occlusion, and recurrent angina are more prevalent in women who undergo surgery. However, long‐term mortality following surgery is similar in men and women.
Ultrafiltration in the treatment of refractory congestive heart failure
Authors: Dileo M. , Bergerone S. , Pozzi R. , Pacitti A. , Tognarelli G. , Segoloni G. , Vercellone A. , Brusca A. 
Published: February 2009

AbstractArtificial subtraction of fluids and solutes was evaluated in the course of acute and chronic heart failure when it became refractory to standard intensive medical treatment. A group of 19 patients (mean age 57 years), 9 with ischemic, 2 amyloidotic, 4 valvular, and 4 idiopathic cardiomyopathy, were treated. In 17 patients extracorporeal ultrafiltration (UF) by means of a polysulfonate ultrafilter was adopted along 125 sessions (105 assisted by a roller pump and 20 as a slow continuous ultrafiltrate). In two patients continuous peritoneal dialysis was adopted. In every case UF was well tolerated. Ultrafiltrate volumes ranged from 1680 to 3500 ml for every session with corresponding Na losses ranging from 194 to 434 mEq/session. Improved clinical and functional status with reduction of edema was observed in 17 of 19 patients. In 12 patients UF could be discontinued due to restored response to diuretics; 5 of these patients could subsequently undergo heart surgery (1 transplant, 3 valve replacement, 1 coronary bypass). The remaining 7 patients survived on medical therapy alone for an average of 228 days. In 7 of 19 cases, UF could not be discontinued, and these patients died after an average of 23 days of treatment. In conclusion, UF proved to be effective in eliminating salt‐fluid overload and restoring response to medical treatment. Patients who are potential surgical candidates seem to be the most suitable for UF.
Comparative cardiac effects of intravenous bolus of ipratropium bromide (itrop) and atropine sulfate in 22 patients
Authors: Libersa C. C. , Caron J. F. , Dupuis B. A. , Kacet S. , Lesenne M. , Werquin S. , Danays T. , Lekieffre J. P. 
Published: February 2009

AbstractAt the present time, there is no satisfactory pharmacological treatment for arrhythmia or conduction disorders induced by or aggravated by vagal hypertonia. The limited duration of action of the atropine derivatives currently available justifies the development of new compounds with expected longer acting duration. The aim of this study was to compare the effects of a single blind intravenous injection of ipratropium bromide to those of atropine sulfate in 22 patients. These patients were studied with continuous Holter recordings for three days. During the second and the third nights (patient sleeping), boluses of atropine (0.03 mg/kg) and of ipratropium bromide (0.03 mg/kg), respectively, were added to a continuous saline intravenous infusion. Accurate ECG analysis allowed determination of maximal heart rate peak, timing of maximal heart rate, variations in sinus cycle length, atrioventricular conduction, and durations of drug action. A nonsuggestive questionnaire was presented to patients to detect possible occurrence of side effects. The mean maximal heart rate rose significantly (p<0.001) for atropine (+46.2%) and for ipratropium bromide (+57.4%). The effects obtained with ipratropium bromide on the heart rate lasted nearly twice as long as those obtained with atropine (respectively, 120±38.4 min and 70±30 min‐ for the pharmacological half‐life). Common minor muscarinic side effects (dryness of the mouth) were noted with the two drugs. In conclusion, this comparative intraindividual study confirmed the prolonged vagolytic effects of intravenous ipratropium bromide, which may be valuable in the treatment of patients with vagally mediated automaticity and conduction disturbances.
Monotherapy of hypertension with darodipine: A new calcium‐channel blocker
Authors: Chrysant S. G. , Chrysant C. , Trus J. , Hitchcock A. 
Published: February 2009

AbstractCalcium‐channel blockers are increasingly used as single agents for the treatment of essential hypertension. Following three weeks of single‐blind placebo therapy, 43 patients with essential hypertension were randomized into four groups. Group 1 (10 patients) received placebo twice a day, Group 2 (13 patients) received darodipine (PY 108‐068) 50 mg twice a day, Group 3 (9 patients) received darodipine 100 mg twice a day, and Group 4 (11 patients) received darodipine 150 mg twice a day. Patients were seen in the clinic weekly for 4 weeks. Clinical and laboratory evaluations were done on each patient. Darodipine caused a sustained decrease in the supine and standing systolic and diastolic blood pressure (p<.001) and there were no significant pressure differences between the three drug dosages. The effects of the drug on heart rate were not consistent. Placebo had no effect on either blood pressure or heart rate. Side effects were few, mild, and consisted of headaches and peripheral edema, and did not necessitate discontinuation of the drug. No metabolic abnormalities were seen with either low or high doses of the drug. We conclude that: (1) darodipine is effective, safe, and well tolerated; (2) its antihypertensive effectiveness is similar at high and low doses, although the higher doses seemed to have a slightly greater effect on the diastolic arterial pressure; (3) the low dose may be preferable since side effects were dose related.