bluuebunny/crossref_metadata_2025_split huggingface dataset:
The implantable defibrillator and antiarrhythmic drugs—competitive and complementary treatment for severe ventricular arrhythmia
Authors: Dorian Paul , Newman David 
Published: February 2009

AbstractMost patients with a history of sustained ventricular tachycardia (VT) or ventricular fibrillation (VF) are at high risk of recurrence. Implanted defibrillators (ICDs) are highly effective in sensing and converting VT or VF to a perfusing rtrythm. “Conventional” antiarrhythmic agents, which primarily block cardiac sodium channels, are relatively ineffective in preventing arrhythmia recurrence; amiodarone and sotalol appear to be effective in reducing recurrence and mortality rates, although the extent of benefit is not well understood. Despite the apparent advantage of ICDs, they have short‐ and long‐term complications, are costly, and their benefit in prolonging the quantity or quality of life remains unproven. Randomized clinical trials which compare the effect of ICDs with that of antiarrhythmic drugs on mortality, cost, and quality of life will be necessary to understand how patients with malignant arrhythmias ought to be treated. If an ICD is implanted, adjunctive therapies need to be considered to treat the underlying heart disease and to derive optimum benefit from the device. Drugs may have beneficial or adverse interactions with devices, and the full understanding of these interactions requires further study.
Coronary artery fistula related to dilatation of totally occluded vessel
Authors: Saad Robert M. , Jain Avanindra 
Published: February 2009

AbstractPercutaneous transluminal coronary angioplasty (PTCA) is widely used to treat patients with coronary artery disease. Experience and improvement in catheters has led to its wider utilization. A case of coronary recanalization, complicated by coronary fistula created by an angioplasty guidewire, is reported.
The utility of nitroderm® TTS® in angina pectoris: Long‐term treatment after switching from long‐acting oral isosorbide dinitrate
Authors: Hayashi H. , Ito T. , Matsubara T. , Watanabe T. , Kuzuya F. , Mizuno Y. , Sotohata I. , Fujinami T. , Toyama J. , Yamada K. 
Published: February 2009

AbstractLong‐acting oral isosorbide dinitrate (ISDN) was replaced by Nitroderm® ITS®, and the utility of this drug in long‐term treatment was assessed in 69 patients with angina pectoris. The frequency of attacks (p < 0.001) and the consumption of sublingual nitrate tablets (p < 0.01) were found to be significantly lower at 2 weeks to 6 months than in the observation period in patients who experienced attacks or received sublingual tablets during the observation period. On the other hand, no significant time‐lapse changes from the observation period were noted in patients who experienced no attacks or received no sublingual tablets during the observation period. The symptoms of adverse effects were mild. The improvement rates (improved) of subjective symptoms and electrocardiogram (ECG) in Group A were about 50% after 6 months. On the other hand, the improvement rates (not aggravated) of subjective symptoms and ECG in Group B were more than 90%. Nitroderm TTS is considered a useful plaster preparation which can be used for sufficiently extended periods of time because its efficacy was as high as, or higher than, that of oral ISDN when this drug was administered over a long period of time after a switch from longacting oral ISDN in angina pectoris patients.
A randomized pilot trial of low‐dose combination lipid‐lowering therapy following coronary artery bypass grafting
Authors: BARBIR M. , HUNT BEVERLEY J. , GALLOWAY D. , TAYLOR ALISON , ILSLEY C. , MITCHELL A. , YACOUB M. 
Published: February 2009

AbstractVein graft atherosclerosis is a common and serious complication of coronary artery bypass grafting (CABG). There is mounting evidence that lipoprotein abnormalities play an equally important role in the development of lesions in saphenous vein grafts after CABG as in native coronary vessel disease. The potential benefit of low‐dose lipid lowering combination therapy in these patients has not been investigated. In a randomized, double‐blind, placebo‐controlled study, we compared the efficacy and safety of a low‐dose combination of colestipol 10 g and simvastatin 10 mg/day (CS) to colestipol 10 mg and bezafibrate 400 mg/day (CB) for 2 months in 33 patients with serum total cholesterol > 6.5 mmol/l and triglyceride < 4.5 mmol/l who had undergone CABG for severe coronary artery disease. In the CS group, total cholesterol decreased by 29% and low‐density lipoprotein (LDL) cholesterol by 42%; similarly, CB reduced total cholesterol by 17%, LDL cholesterol by 23%, triglyceride by 19%, and increased high‐density lipoprotein (HDL) cholesterol by 14%. Lipoprotein (a) and hemostatic factors were unaffected by either therapy in this study. Both combination therapies were well tolerated with no significant clinical or biochemical side effects. We conclude that low‐dose combinations of colestipol and simvastatin or colestipol and bezafibrate are effective and well tolerated in the management of moderate hyperlipidemia in patients who had undergone CABG.
Torsade de pointes complicating drug treatment of low‐malignant forms of arrhythmia: Four case reports
Authors: Faber T. S. , Zehender M. , Van Loo A. De , Hohnloser S. , Just H. 
Published: February 2009

AbstractIn patients with malignant ventricular arrhythmias, antiarrhythmic therapy is known to carry a substantial risk of proarrhythmia. This risk is usually considered to be low when supraventricular arrhythmias or benign ventricular arrhythmias are considered. We were able to collect data on four patients without a history of life‐threatening arrhythmias, in whom antiarrhythmic therapy was used and resulted in documented ventricular fibrillation or torsade de pointes. In Cases No. 1 and 2, atrial fibrillation was treated with either quinidine or quinidine and sotalol in combination. In both patients Holter monitoring, 4‐12 h after conversion to sinus rhythm, documented the spontaneous occurrence of torsade de pointes degenerating into ventricular fibrillation and requiring DC shock for termination. In Case No. 3, atrial fibrillation was treated with sotalol and amiodarone for 2 months when incessant episodes of torsade de pointes were documented. In Case No. 4, frequent but unsustained ventricular arrhythmias were treated with amiodarone in a patient suffering dilative cardiomyopathy. After 6 days of treatment at a heart rate of 54 beats/min, a marked QT increase was associated with the occurrence of repetitive episodes of polymorphic ventricular tachycardia degenerating into ventricular fibrillation. None of the patients presented significant electrolyte abnormalities in the laboratory. A pathologic increase of the QTc‐time was documented in Cases No. 1, 3, and 4. In all patients antiarrhythmic therapy was withdrawn after the proarrhythmic event and the patient became free of malignant tachyarrhythmias. Antiarrhythmic therapy also carries a considerable risk of proarrhythmia when “benign” cardiac arrhythmias are treated. The risk seems to be lower than in patients with malignant arrhythmias, however it includes the occurrence of lethal tachyarrhythmias. Special attention should be paid to the selection of antiarrhythmic agents when used in combination.
Noninvasive localization of accessory pathways by magnetocardiographic imaging
Authors: Nomura Masahiro , Nakaya Yutaka , Saito Ken , Kishi Fumiko , Watatsuki Tetsuzo , Miyoshi Hirokazu , Nishikado Akiyoshi , Bando Shigenobu , Ito Susumu , Nlshltanl Hiromu , Wada Masao , Fujita Satoshi , Tamura Itsuro 
Published: February 2009

AbstractThe magnetocardiogram (MCG) is a newly developed method that helps localize a cardiac current source. To test the clinical accuracy of a 7‐channel biomagnetic system in the localization of early ventricular depolarization sites, the MCGs of 14 patients with Wolff‐Parkinson‐White (WPW) syndrome were recorded in a radiofrequency‐shielded room. The locations of early ventricular depolarization sites were classified by standard 12‐lead electrocardiograms (ECGs) and body surface iso‐potential mapping. The accessory pathways of 3 patients with WPW syndrome were located in the right free wall and in 11 patients in the left free wall. The three‐dimensional (3‐D) dipole location was computed every 2 ms from the onset of the QRS complex by the least‐square method. These 3‐D dipole locations were projected onto a gated magnetic resonance image in order to visualize the propagation of the calculated ventricular source. The results were compared with those obtained by body surface isopotential mapping, and electrocardiographic and electrophysiologic studies. The location of the deduced current dipole at 20 ms correlated well with the location of the accessory pathway by the body surface mappings in 12 of the 14 patients with WPW syndrome. The MCG is capable of precisely determining the 3‐D location of a current source in a noninvasive manner and may be of potential benefit in the treatment of WPW syndrome by catheter ablation.
Bisoprolol, a once‐a‐day beta‐blocking agent for patients with mild to moderate hypertension
Authors: Davidov Michael E. , Singh Sant P. , Vlachakis Nicolas D. , Blumenthal Jerome B. , Simon Joseph S. , Bryzinski Brian S. , Koury Kenneth J. , Alemayehu Demissie 
Published: February 2009

AbstractThe 24‐h blood pressure control of bisoprolol, a new beta1‐selective, beta‐blocking agent, was studied in 240 mild to moderate hypertensive patients in this 4‐week, randomized, double‐blind, placebo‐controlled trial. A once‐daily dosing schedule was evaluated by comparing bisoprolol's antihypertensive effectiveness and safety at 24 h postdose and 3 h postdose, the latter time intended to correspond to peak effectiveness. Results from this trial demonstrated the antihypertensive effectiveness of once‐daily bisoprolol at doses ranging from 5‐20 mg. Mean reductions from baseline diastolic blood pressure, measured 24 h postdose, were 6.3,8.8, and 10.1 mmHg for patients receiving bisoprolol 5, 10, and 20 mg, respectively, compared with 1.6 mmHg for placebo‐treated patients (p< 0.01); mean reductions from baseline systolic blood pressure for the bisoprolol groups were 8.6, 8.6, and 10.9 mmHg, respectively, versus 3.3 mmHg for placebo (p≤0.01); and mean reductions from baseline heart rate for the bisoprolol groups were 5.1,7.1, and 10.2 beats/min, respectively, compared with a 0.9 beats/min increase in heart rate for the placebo group (p < 0.01). The response rates for bisoprolol‐treated patients ranged from 47 to 70% compared with 18% for patients on placebo (p < 0.01). Antihypertensive effects were dose‐related and sustained over the 24‐h dosing interval. Near maximal antihypertensive effects were achieved within 1 week of initiation of therapy with bisoprolol and were sustained over the course of the trial.The antihypertensive effects of bisoprolol were accompanied by a favorable safety profile. Furthermore, bisoprolol was welltolerated and did not differ significantly from placebo in either the frequency or severity of reported adverse experiences. Withdrawal rates for adverse events were 1.4% for the placebo group versus 1.9% for the composite bisoprolol group. Laboratory changes generally were related to small increases within the normal range and were not clinically relevant. No bisoprolol‐treated patient left the study or interrupted treatment for a clinical laboratory abnormality.
Urinary carnitine excretion in patients with heart failure
Authors: Matsui Shinobu , Sugita Toshiro , Matoba Munetoshi , Murakami Eiji , Takekoshi Noboru , Shinka Toshihiro , Matsumoto Isamu 
Published: February 2009

AbstractTo evaluate the fatty acid metabolism in heart failure, the semiquantitative analysis of urinary free carnitine and acylcarnitine was made by fast atom bombardment mass spectrometry (FABMS) in 22 patients (mean age 67.3 years) with heart failure and 19 age‐matched healthy controls (average age 60.4 years). Urinary excretion of free carnitine was 0.20 ± 0.118 ratio/mg creatinine in the healthy controls and 1.32 ± 1.170 ratio/mg creatinine in the patients with heart failure. The latter value was significantly higher (p < 0.01 ). Patients with heart failure were classified into two groups according to the urinary free carnitine concentration. One was the high excretion group (2.19 ± 0.102 ratio/mg creatinine, 12 cases) and the other was the low excretion group (0.37 ± 0.212 ratio/mg creatinine, 10 cases). In the high excretion group, urinary acetylcarnitine was also increased, but no significant abnormalities were observed in the urinary organic acid profile. In the high group, 1 patient was classified as NYHA class III and 11 as NYHA class IV. Four patients died in the hospital. In the low excretion group, five patients were classified as NYHA class III and five as NYHA class IV. Only one patient died in the hospital. In the high group, patients with severe and prolonged heart failure tended to maintain higher values of urinary free carnitine. We could not find any abnormalities in fatty acid metabolism in patients with heart failure, but it is suspected that the patients who excrete large amounts of free carnitine into the urine, namely the patients with severe heart failure, have some possibility of carnitine deficiency.
Fatal intracerebral hemorrhage following thrombolytic therapy of embolic myocardial infarction in unsuspected infective endocarditis
Authors: Di Salvo Thomas G. , Tatter Stephen B. , O'Gara Patrick T. , Nielsen Gunnlaugur P. , Desanctis Roman W. 
Published: February 2009

AbstractCerebral hemorrhage occurs in 0.2% of patients under the age of 60 years treated with thrombolytic therapy for acute myocardial infarction. A case of fatal cerebral hemorrhage following TPA therapy for myocardial infarction due to probable coronary artery embolism during unsuspected native valve infective endocarditis is reported.
Lactate threshold is not an onset of insufficient oxygen supply to the working muscle in patients with chronic heart failure
Authors: Yamabe Hiroshi , Itoh Kazushi , Yasaka Yoshinori , Takata Teruo , Yokoyama Mitsuhiro 
Published: February 2009

AbstractIt has been argued that the lactate threshold (LT) serves as an index to reflect circulatory insufficiency in transporting oxygen during submaximal exercise in patients with chronic heart failure (CHF). We examined whether or not the LT was related to an insufficient oxygen supply in patients with CHF. Sixty‐nine patients were divided by NYHA classification. All underwent invasive cardiopulmonary exercise testing. The rate of increase in oxygen delivery (O2D) versus VO2 (ΔO2D/ ΔVO2) was significantly lowered when work rate exceeded LT, that is, 1.32 ± 0.35 to 1.05 ± 0.37 (p < 0.01), 1.22 ± 0.40 to 0.98 ± 0.40 (p < 0.05), and 1.04 ± 0.26 to 0.78 ± 0.39 (p < 0.05) in NYHA classes I, II, and III, respectively. However, the rate of increase in leg O2D versus leg VO2 (ΔLO2D/ΔLVO2) did not change, that is, 1.25 ± 0.20 to 1.29 ± 0.20 (NS), 1.27 ± 0.23 to 1.21 ± 0.28 (NS), and 1.19 ± 0.24 to 1.15 ± 0.17 (NS) in classes I, II, and III, respectively. Leg venous PO2 was significantly different among three groups, that is, 23.7 ± 3.4 mmHg, 23.2 ± 2.8 mmHg, and 20.1 ± 2.3 mmHg (p < 0.001), respectively. Thus, the oxygen supply to the working muscle did not become insufficient when work rate exceeded LT, and the LT occurred at different levels of leg PO2. It was concluded that the LT was not a result of anaerobiosis in patients with CHF.
Postoperative hemodynamic improvement with paced linkage of the donor and recipient hearts following heterotopic cardiac transplantation
Authors: Cowell R. , Morris‐Thurgood J. , Coghlan J. , Paul V. , Mitchell A. , Khaghani A. , Ilsley C. , Yacoub M. 
Published: February 2009

AbstractIt has been shown that following heterotopic heart transplantation the recipient left ventricle ejects more effectively when it contracts out of phase with the donor left ventricle. However, this is rarely the situation, as the two hearts beat independently of one another and the denervated donor heart tends to beat faster than the recipient. In this study the hemodynamic effects of connecting the two hearts by an external temporary dual‐chamber pacemaker were evaluated. The donor right ventricle was sensed and the recipient right atrium paced after a timed delay. The delay was adjusted so that recipient systole coincided with donor diastole. Eleven patients were studied in the first postoperative day. Pacing resulted in an improvement in cardiac output from 5.0 to 5.61/min (p = 0.003) and a reduction in pulmonary capillary wedge pressure from 16 to 12 mmHg (p = 0.0035). This was associated with a 35% reduction in inotrope requirements. It is concluded that sequential pacing of the two hearts is a useful adjunct to inotropic support in the postoperative period.
The severity of residual coronary stenosis immediately after thrombolytic therapy does not influence the size of later left ventricular asynergic area
Authors: Fukunaga Takashi , Hanada Yuhji , Koiwaya Yasushi , Eto Tanenao 
Published: February 2009

AbstractTo determine whether the severity of residual coronary artery stenosis immediately after thrombolytic therapy influences the size of later left ventricular (LV) asynergic area, we reviewed coronary angiograms (CAGs) and left ventriculograms (LVGs) of 31 patients with acute myocardial infarction (AMI). All patients received intracoronary urokinase therapy within 6 h after onset of AMI due to total occlusion of the proximal left anterior descending coronary artery (LAD). A dose of 960,000 IU urokinase was infused into the ostium of the left coronary artery over 40 min. Patients in whom antegrade blood flow without delayed distal filling was restored received rigorous anticoagulation. The patients were divided into three groups according to the severity of the coronary lesion immediately after urokinase therapy: 9 patients with complete occlusion in Group 1, 15 with > 90% stenosis in Group 2, and 7 with <90% stenosis in Group 3. There were no significant differences in the baseline clinical characteristics among the patients in the three groups. The LADs in Group 1 were also totally occluded 1 month after urokinase therapy, the treated vessels in both Groups 2 and 3 were still patent, and patients in Group 2 showed a further reduction in residual stenosis. When LV asynergic area, regional wall motion, and global ejection fraction (EF) were compared among the three groups, no significant differences were demonstrated. in comparison with the data immediately after urokinase therapy, all parameters 1 month after therapy were significantly improved in both Groups 2 and 3. However, there was no significant difference in the improvement of these parametere between Groups 2 and 3 despite significant differences in residual stenosis of the LADs immediately after urokinase
Noninvasive evaluation of contractile state by left ventricular dP/dtmax divided by end‐diastolic volume using continuous‐wave doppler and M‐mode echocardiography
Authors: Kawai Hiroya , Yokota Yoshiyuki , Yokoyama Mltsuhiro 
Published: February 2009

AbstractThe maximum rate of left ventricular (LV) pressure rise (dP/dtmax) is commonly used in the assessment of directional change in LV contractility and, recently, estimated by analyzing continuous‐wave Doppler ultrasound velocity curve of mitral regurgitation. As an alteration in ventricular preload is known to affect dP/dtmax, normalized dP/dtmax for preload might be more reliable to assess LV contractile state. To investigate the usefulness of a new index of LV contractile state determined by continuous‐wave Doppler analysis of mitral regurgitation and M‐mode echocardiogram‐derived LV end‐diastolic volume, we studied 18 patients with mild mitral regurgitation. The continuous‐wave Doppler velocity curves of mitral regurgitation were digitized and converted to instantaneous pressure gradient between the LV and left atrium using the simplified Bernoulli equation. The maximum value of its first derivative (Doppler‐derived dP/dtmax) correlated well with LV dP/dtmaxusing simultaneously recorded LV pressures by manometer‐tipped catheter (n = 20, r = 0.97, p < 0.001). Corrected Doppler‐derived dP/dtmax for LV end‐diastolic volume using Teichholz's method significantly increased by inotropic stimulation with dobutamine (p < 0.01); however, it remained unchanged by augmentation of afterload with angioteasin II. Thus, the LV dP/dtmax can be accurately estimated in humans by analyzing the continuous wave Doppler velocity curve of mitral regurgitation, and corrected Doppler‐derived dP/dtmax for LV end‐diastolic volume is relatively independent of loading alteration and sensitive to inotropic stimulation. We concluded that echocardiographic assessment by combined Doppler‐ and M‐mode measurements provides a useful and sensitive index of LV contractile state noninvasively.
Pathology of tricuspid valve stenosis and pure tricuspid regurgitation—Part I
Authors: Waller Bruce F. , Howard Jane , Fess Stephen 
Published: February 2009

AbstractThis three‐part article examines the histologic and morphologic basis for stenotic and purely regurgitant tricuspid valves. In Part I, conditions producing tricuspid valve stenosis are reviewed. In over 90% of stenotic tricuspid valves, the etiology is rheumatic disease. In isolated tricuspid stenosis, the etiology is either carcinoid or congenital. Rare causes of tricuspid stenosis include active infective endocarditis, metabolic or enzymatic abnormalities (Fabry's, Whipple's disease), and giant blood cysts.
Enoximone versus epinephrine/nitroglycerin in cardiac low‐output states following valve replacement
Authors: Zwölfer Werner , Keznickl Paul , Dressler Helmut T. , Dieterich Hans A. 
Published: February 2009

AbstractThis prospective, randomized, comparative study was designed to assess the inotropic and vasodilatory effects of the selective phosphosidesterase III inhibitor enoximone compared with standard therapy with epinephrine/nitroglycerin in patients with refractory low output states following cardiac valve replacement. Enoximone possesses inotropic and vasodilatory properties and has proven to be of beneficial effect in patients suffering from severely impaired myocardial function. Six patients in each group received either enoximone bolus‐infusion of 0.5 mg/kg over 10 min followed by an infusion of 5 m̈g/kg/min up to 20 m̈g/kg/min or epinephrine and nitroglycerin infusion of 0.05 and 0.5 m̈g/kg/min, respectively, for 4 hours postoperatively. Hemodynamic effects of enoximone and the combination of epinephrine/nitroglycerin were compared. Both treatments led to positive inotropy with a simultaneous decrease in filling pressures and vascular resistances. The results indicate that enoximone in low‐output states following cardiac valve replacement was at least equally effective in comparison with standard therapy with epinephrine and nitrolycerin.