bluuebunny/crossref_metadata_2025_split huggingface dataset:
Provocation of ventricular tachycardia by antimalarial drug halofantrine in congenital long QT syndrome
Authors: Toivonen Lauri , Viitasalo Matti , Pohjola‐Sintonen Sinikka , Siikamäki Heli , Raatikka Marja 
Published: February 2009

AbstractThis report deals with two patients who suffered sustained episodes of torsade de pointes ventricular tachycardia while using the novel antimalarial drug halofantrine. Both patients had congenital long QT syndrome, and their QT interval was further prolonged at the time of the event. This first electrocardiographic documentation of ventricular arrhythmias together with halofantrine's known prolonging effect on the QT interval demonstrates that the drug has the potential to induce life‐threatening arrhythmias.
Concomitant use of nitrates, calcium channel blockers, and beta blockers for optimal antianginal therapy
Authors: Cohn Peter F. 
Published: February 2009

AbstractDespite the introduction of new mechanical techniques for revascularization, pharmacologic therapy continues to be the mainstay of antianginal therapy. The conventional antianginal medications, which include nitrates, beta blockers, and calcium channel blockers, act to correct the imbalance between myocardial supply and demand by increasing coronary blood flow, reducing myocardial oxygen requirements, or both. All three are appropriate for the management of angina caused by a fixed coronary obstruction, but nitrates and calcium channel blockers, which not only reduce demand but also increase supply, are preferred in cases of angina believed to involve a significant increase in vasomotor tone. Because of the different yet complementary mechanisms of action of the three classes of anti‐ischemic drags, use of these agents in combination is a rational approach to the treatment of angina unresponsive to monotherapy. Such combinations have been shown to enhance the therapeutic response achieved with single‐agent therapy. In addition, the pharmacologic action of one of the components of the combination regimen may serve to offset side effects typically associated with the other.
ST‐segment computerized monitoring before and after angioplasty: Clinical correlation with recurrent angina during the short‐term follow‐up
Authors: Gurfinkel E. , Duronto E. , Manos E. , García N. , Mejaíl R. , Mendiz O. , Cerdá M. , Mautner B. 
Published: February 2009

AbstractThe purpose of this study was to determine whether computerized ST‐segment monitoring previous to percutaneous transluminal coronary angioplasty (PTCA) and after performance of this procedure may be useful to discern a pattern of recurrent angina. For this purpose, we analyzed 57 patients (11 women and 46 men, mean age 60 years) before and after treatment with balloon procedure. These patients were followed up during the next 3 months. A computerized electrocardiographic (ECG) device was used which was capable of recording simultaneously all 12 leads at rest. It was programmed to store a complete ECG every 5 min and was capable of detecting any abnormal ST alteration > than 0.5 mV at 80 ms after J junction, including R‐wave amplitude. Measurements were started before (mean time 7.26 h) and after (mean time 7.96 h) the procedure. The value for ST amplitude at the J junction was used as the 0 point; then the most negative depression or the most positive elevation value was considered as the most abnormal ST alteration during monitoring. The patients were followed up for 3 months for the purpose of recognizing recurrent angina or establishing the occurrence of death. Twelve patients (30%) had recurrent angina. Discriminant function analysis revealed that ST monitoring in these patients showed significant difference after PTCA in comparison with controls, both in the frontal plane [ST depression 170 ± 52 mV vs. 231 ± 23 (p = 0.02)J and in precordial leads [176 ± 16 vs. 80 ± 6.19 mV (p = 0.0001)]. Among patients who had no recurrent angina there were significant changes in the horizontal plane [171 ± 18.3 mV vs. 156 ± 14.7 mV (p = 0.007)] but not in the frontal plane [213 ± 17.67 mV vs. 195 ± 75.2 mV (p = NS)]. There were no significant changes when the ST slope was evaluated as elevated among patients with or without recurrent angina. In this pilot study, the computer method using continuous recording data to determine whether significant differences existed among groups showed that ST‐segment depression in the frontal leads before PTCA could contribute to identifying a group of patients at risk of developing recurrent angina soon after PTCA.
Transesophageal echocardiography in the intensive care unit: Impact on diagnosis and decision‐making
Authors: Chenzbraun Adrian , Pinto Fausto J. , Schnittger Ingela 
Published: February 2009

AbstractTransesophageal echocardiography (TEE) is widely used in the management of patients in intensive care units. The present study assesses the specific value of this technique in various categories of these patients. We reviewed 113 studies performed in 100 such patients for: suspected aortic dissection (25), suspected endocarditis (33), source of emboli assessment (19), hemodynamic instability (15), and miscellaneous (21). TEE provided diagnostic information in all patients with aortic dissection, in 53% of the cases with hemodynamic instability, in 50% of the cases with septic states with high likelihood of endocarditis, and in 29% of the cases where the question was the source of emboli. When the clinical probability for endocarditis was low, all transesophageal echocardiograms performed in septic patients were negative. The information provided by TEE was considered crucial in one‐third of the positive cases; in about one‐half of these special cases, the results were instrumental for further surgical management. There were no significant side effects related to the procedure. TEE is easily performed in the intensive care unit setting and yields useful information in almost half of the cases. Special benefit is expected in suspected aortic disease, hemodynamic instability, suspected endocarditis, and embolic events. The overall yield as screening procedure in febrile patients is low.
The effect of limited handrail support on total treadmill time and the prediction of vo2 max
Authors: Manfre Michael J. , Yu Guan‐Hiok , Varmá Andre A. , Mallis George I. , Kearney Kevin , Karageorgis Mario A. 
Published: February 2009

AbstractHolding onto the front handrail during treadmill testing significantly increases total treadmill time (TT) and predicted VO2 max when compared with tests without front handrail support. By limiting the amount of handrail support to the tips of two fingers of one hand, the difference in TT can be substantially reduced. In the present study, the difference in TT between tests with and without handrail support for healthy men was not significantly different. However, this was not true for healthy women and for male patients with coronary artery disease and myocardial infarction.
Clinical value of transesophageal atrial stimulation and recording in patients with arrhythmia‐related symptoms or documented supraventricular tachycardia—correlation to clinical history and invasive studies
Authors: Pehrson Steen M. , Blomströ‐LUNDQVIST Carina , Ljungströ Erik , Blomströ Per 
Published: February 2009

AbstractThe main objective of the present study was to evaluate the clinical applicability of transesophageal atrial stimulation (TAS) and recording with regard to inducibility of supraventricular tachycardia (SVT) in patients with either an ECG‐documented paroxysmal SVT or a clinical history of palpitations suggesting this disease. A further objective was to assess the inducibility of SVT and to compare the inducibility by TAS with that obtained by an invasive electrophysiologic study (EPS). A total of 64 patients (aged 13‐74 years) with ECG‐documented paroxysmal SVT (n = 50) or only a history of palpitations (n = 14) was referred for TAS. Preexcitation was present in 35 patients. The study protocol included single and double extrastimuli delivered at a basic paced interval of 500 ms, and incremental atrial stimulation until a cycle length of 275 ms or a second‐degree AV block appeared. In 10 patients atropine intravenously was required for induction. The same protocol was used in 34 of the patients who also underwent invasive EPS. TAS was completed in 56 of 64 patients (88%). In this group SVT was induced during TAS in 84% (47/56). Of patients with ECG‐documented tachycardia, clinical tachycardia was induced in 90% (35/39) with ECG‐documented regular paroxysmal SVT and in 67% of patients (4/6) with ECG‐documented atrial fibrillation. In patients without ECG‐documented tachycardia, clinically relevant arrhythmia was induced in 73% (8/11). In 30 of 32 patients (94%) with an inducible tachycardia during invasive EPS, it was also possible to induce the tachycardia by TAS. We concluded that TAS is a simple and noninvasive diagnostic tool for evaluation of clinical arrhythmia in patients with documented or suspected paroxysmal SVT. The inducibility of SVT seems comparable to that obtained by invasive EPS.
Spontaneous echo contrast on transthoracic echocardiography and left atrial thrombus in rheumatic mitral valve disease patients: A clinicopathologic study
Authors: Wanishsawad Chad , Puavilai Wilai , Roongsrttong Chanwtt , Sitthi‐Amorn Chitr 
Published: February 2009

AbstractThe association of spontaneous echo contrast and thrombus in the left atrium in patients with mitral valve disease is controversial. This study was undertaken to determine whether there is an independent association between spontaneous echo contrast on transthoracic echocardiography (TTE) and intraoperative evidence of left atrial thrombus and to evaluate the clinical implications of spontaneous echo contrast in patients with symptomatic rheumatic mitral valve disease. A total of 255 patients who underwent surgery for rheumatic mitral valve disases were preoperatively evaluated by transthoracic two‐dimensional and Doppler echocardiography. Spontaneous echo contrast in the left atrium was carefully sought. The left atrium was carefully searched for evidence of thrombus intraoperatively. The association of spontaneous echo contrast and left atrial thrombus was determined by univariate and multivariate analysis. Of the patients studied, 77 (30%) had left atrial thrombus. Left atrial thrombus was found in 47 and 21 % of patients with and without spontaneous echo contrast, respectively (p < 0.001). Spontaneous echo contrast and atrial fibrillation were found to be the only two independent predictors of left atrial thrombus (odds ratio = 2.16; 95% confidence interval 1.15‐4.04 p < 0.05, and odds ratio = 6.98; 95% confidence interval 3.45‐14.16, p < 0.001, respectively). It was concluded that there is an independent association between spontaneous echo con trast on TTE and left auial thrombus in patients with mitral valve disease requiring surgical correction. These patients are at high risk for left atrial thrombus and should, therefore, be con sidered for long‐term anticoagulation.
Emergency and long‐term extracorporeal life support following acute myocardial infarction: Rescue from severe cardiogenic shock related to stunned myocardium
Authors: Kurose Mrsuro , Okamoto Kazufumi , Sato Toshihide , Kukita Ichiro , Taki Kenichiro , Goto Hiraaki 
Published: February 2009

AbstractThere has been no report regarding therapy of extracorporeal life support (ECLS) that showed stunned myocardium echocardiographically and electrocardiographically in patients with acute myocardial infarction. ECLS was performed in eight patients with cardiogenic shock or arrest unresponsive to catecholamines and intra‐aortic balloon pumping following myocardial infarction; these patients required prolonged external cardiac massage. After the initiation of ECLS, both blood pressure and metabolic acidosis improved in all patients. Four of eight patients were weaned from ECLS after a mean of 69.3 h, which was far longer than previously reported in patients with ischemic heart disease. Three of these patients survived, and cardiac function recovered to NYHA class II in two of the survivors and class III in the other. The other five patients did not recover from coma during ECLS and died. A marked improvement of ventricular wall motion was seen in two survivors with the disappearance of pathologic Q waves after the initiation of ECLS. No occlusion of the coronary arteries or bypass grafts was observed in any of the survivors. These findings suggested the existence of stunned myocardium with myocardial reperfusion. The recovery of stunned myocardium may be delayed for days or even weeks, hence the extended period of ECLS therapy was theoretically justifiable. We conclude that long‐term ECLS is a useful therapeutic method for patients with severe cardiogenic shock that is related to stunned myocardium.
Refractory hypoxemia in inferior myocardial infarction from right‐to‐left shunting through a patent foramen ovale: A case report and review of the literature
Authors: Silver Marc T. , Lieberman Eric H. , Thibault George E. 
Published: February 2009

AbstractRight ventricular (RV) infarction is a well‐recognized complication of some acute inferior myocardial infarctions. Recently, there have been numerous case reports of RV infarctions complicated by severe refractory hypoxemia secondary to right‐to‐left shunting through a patent foramen ovale. An additional case missed by transthoracic echocardiography and cardiac catheterization is reported and the English literature on the subject is reviewed.
Bilateral renal artery occlusion: An unusual presentation of atrial fibrillation and hypertrophic cardiomyopathy
Authors: Fu Gene Y. , Candela Richard J. , Yakubov Steven J. , Mishkind Michael , Obarski Timothy 
Published: February 2009

AbstractHypertrophic cardiomyopathy predisposes patients to atrial fibrillation and the development of systemic embolization. We describe a rare case of bilateral renal artery thrombosis which presented as acute renal failure requiring dialysis. The patient was successfully treated with a selective, continuous infusion of urokinase which resulted in the return of adequate renal function.
Sleep apnea and complete heart block
Authors: Rama Pamela R. , Sharma Satish C. 
Published: February 2009

AbstractSleep apnea has been associated with various types of cardiac dysrhythmias; however, complete heart block has not been reported to occur in this condition. This brief report describes the case of a patient who developed episodes of prolonged complete heart block during sleep apnea. Nasal continuous positive airway pressure resulted in complete resolution of the heart block.
Risk indicators for death and prognosis among patients in whom acute myocardial infarction was not confirmed in relation to prescription of beta blockers at discharge
Authors: Herlitz J. , Karlson B. W. , Hjalmarson ÅA. 
Published: February 2009

AbstractA large number of studies have shown the prognosis after acute myocardial infarction (AMI) to be favorably affected by treatment with beta blockers. Whether such treatment also will have a favorable effect on the prognosis in patients in whom AMI was not confirmed has not been shown. A study was undertaken at Sahlgren's Hospital, Göoteborg, to determine risk indicators for death and prognosis among 1,443 patients in whom AMI was not confirmed and who survived hospitalization in relation to whether or not beta blockers were prescribed at discharge. One‐year mortality was determined and p values were corrected for differences at baseline. Of the 1,443 patients who participated in the analyses, 44% were prescribed beta blockers. They differed from the remaining patients by younger age, predominance of men, a more frequent history of AMI, angina pectoris, and hypertension, and a less frequent history of congestive heart failure. Patients in whom beta blockers were prescribed had a 1‐year mortality of 6% compared with 16% in those not on beta blockers (p < 0.001). The difference was similar in various subgroups according to clinical history.
Percutaneous transluminal coronary angioplasty versus thrombolysis in acute myocardial infarction: A meta‐analysis
Authors: Vaitkus Paul T. 
Published: February 2009

AbstractWhile percutaneous transluminal coronary angioplasty (PTCA) as a primary modality for treating acute myocardial infarction (MI) has been shown to have important advantages over thrombolysis, a survival benefit has not been demonstrated because of the small size of the individual trials. To increase the statistical power to detect a survival benefit, we performed a meta‐analysis of trials of PTCA and thrombolysis. We pooled the data for all randomized, controlled trials; randomized, controlled trials stratified according to thrombolytic agent [streptokinase vs. tissue plasminogen activator (TPA)]; and all trials. Pooling was performed by calculating the Mantel‐Haenszel odds ratio with the Robins, Greenland, and Breslow estimate of variance. Calculation of the Q statistic was performed to assess heterogeneity. For all four analyses, the odds ratio indicated a significant survival advantage of PTCA over thrombolysis: all randomized controlled trials [0.57,95% confidence index (CI): 0.48,0.68)]; streptokinase trials [0.61,95% CI: 0.43,0.87); TPA trials (0.52,95% CI: 0.36,0.76); all trials (0.51,95% CI: 0.43,0.61). The Q statistic was not significant for any of the analyses. The results of our meta‐analysis support the hypothesis that PTCA is associated with a significant reduction in mortality compared with thrombolysis.
Successful radiofrequency catheter ablation of atrial muscle reentry tachycardia in a young adult
Authors: Douglas Dane E. , Case Christopher L. , Shuler C. Osborne , Gillette Paul C. 
Published: February 2009

AbstractAtrial muscle reentry as a mechanism of tachycardia has been well illustrated in isolated animal atrial muscle. It has infrequently been reported as an etiology of supraventricular tachycardia in young patients. A case of atrial muscle reentry tachycardia and its successful elimination using radiofrequency catheter and its successful elimination using radiofrequency catheter ablation is reported.
Is ventricular wall stress rather than left ventricular hypertrophy an important contributory factor to sudden cardiac death?
Authors: James Michahl A. , Macconnell Thomas J. , Jones John V. 
Published: February 2009

AbstractSudden cardiac death comprises a significant proportion of cardiac mortality in Western society. Left ventricular hypertrophy has been identified by many authors as a possible risk factor for sudden cardiac death, however, left ventricular hypertrophy develops in response to external stimuli on the heart as a means of normalizing wall stress. It is possible that the fundamental abnormalities in wall stress, rather than the left ventricular hypertrophy itself, pose the increased risk of sudden death. Left ventricular hypertrophy, the consequence of raised wall stress, is easy to measure and easy to study and it is understandable why this parameter should have received more attention. Wall stress by contrast is difficult to measure, and worse, is variable throughout the ventricle so that it cannot be measured in a single quantifiable figure. As a consequence, only a limited amount of attention has been paid to wall stress as a possible trigger mechanism for cardiac arrhythmia. However, there is evidence from both basic and clinical research to suggest that raised wall stress may be a risk factor for sudden cardiac death and cardiac arrhythmia. This review discusses the evidence for and against left ventricular hypertrophy and wall stress as risk factors for sudden cardiac death, and also presents recent evidence that left ventricular hypertrophy in isolation can protect the heart against the arrhythmogenic effects of raised wall stress.
Complications of warfarin therapy monitored by the international normalized ratio versus the prothrombin time ratio
Authors: Andrews Thomas C. , Peterson David W. , Doeppenschmidt Dennis , Foster Jeff S. , Lucca Michael J. , Deering Joseph A. , Laveau Paul J. 
Published: February 2009

AbstractThe objective of our study was to determine the rates of bleeding complications and thromboembolic events in patients receiving oral anticoagulant therapy monitored with the prothrombin time (PT) ratio versus therapy monitored with the International Normalized Ratio (INR) using a retrospective time‐series study design. Over 650 patients enrolled in a large anticoagulation clinic were studied during two time periods corresponding to the use of the PT ratio versus the INR to guide anticoagulant therapy, with over 400 patient‐years of follow‐up for each time period. The rate of bleeding complications using the PT ratio to guide therapy was 6.7% (1.2% major, 5.5% minor) per patient‐year, compared with 2.9% (0% major, 2.9% minor) using the INR (p = 0.02). The rate of thromboembolic complications was 1.0% using the PT ratio, compared with 0.2% using the INR (p = NS). Therapy monitored with the INR required 19.8 visits per year, compared with 20.7 visits per year using the PT ratio. We conclude that the INR should be used to monitor oral anticoagulant therapy in an effort to reduce bleeding complications while maintaining an acceptable rate of thromboembolic events.
Importance of the time of onset of supraventricular tachyarrhythmias on prognosis of patients with acute myocardial infarction
Authors: Serrano Carlos V. , Antǒnio José , Ramires F. , Mansur Antǒnio P. , Pileggi Fúlvio 
Published: February 2009

AbstractIt is known that left ventricular (LV) function, severity of coronary artery disease, and the presence of ventricular arrhythmias are major determinants of prognosis in patients surviving an acute myocardial infarction (AMI). However, little is known about the relationship between the time of onset of supraventricular tachyarrhythmias (SVTs) and mortality. Therefore, this study was carried out in a 48‐month period on 131 patients with AMI who presented with SVT during hospitalization. Of these, 53 patients (40.5%) had arrhythmia within < 12 h of MI, while 78 patients (59.5%) had arrhythmia between 12 h and 4 days. The arrhythmias studied were atrial fibrillation, atrial flutter, and paroxysmal supraventricular tachycardia. The patients were similar for age, gender, coronary risk factors, creatine kinase‐MB peak, cardioversion and LV function. Angiographic features for patients with the < 12‐h onset of arrhythmia were: 86.7% of the patients had uniarterial lesions, 8.9% had biarterial lesions, and 4.4% had triarterial lesions. Patients with the 12‐h‐4‐day onset had 16.1%, 53.2%, and 30.6% (p≤0.05) of the respective lesions. Inferior wall myocardial infarction was more frequent among patients with the earlier onset (60.4%), while patients with the later onset presented more anterior wall infarctions (50.0%). Only 11.3% of the patients with the earlier onset presented with severe in‐hospital congestive heart failure (Killip classes III‐IV), versus 62.8% of the patients with the later onset (p≤0.0001). Patients with the earlier onset of arrhythmia had fatality rates of 7.6 and 15.1% during the first month and subsequent 47 months post‐MI, respectively, while the other set of patients presented rates of 37.2 (p≤0.0003) and 24.4% (p≤0.01), respectively. These data suggest that the relationship between SVT occurrence between 12 h and 4 days after MI and poor prognosis is apparently linked to the occurrence of more severe coronary artery disease in these patients.