Journal of the American College of Cardiology
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J. Am. Coll. Cardiol. · Jun 1994
Randomized Controlled Trial Clinical TrialEfficacy of spinal cord stimulation as adjuvant therapy for intractable angina pectoris: a prospective, randomized clinical study. Working Group on Neurocardiology.
In a prospective, randomized study with an 8-week follow-up period, we evaluated the efficacy of spinal cord stimulation on exercise capacity and quality of life in patients with intractable angina. ⋯ Spinal cord stimulation significantly improves exercise capacity and quality of life. On the basis of an increase in exercise capacity and rate-pressure product, the mechanism by which spinal cord stimulation acts may be related to improved oxygen supply to the heart combined with an analgesic effect.
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J. Am. Coll. Cardiol. · Jun 1994
Aminophylline fails to improve the outcome of cardiopulmonary resuscitation from prolonged ventricular fibrillation: a placebo-controlled, randomized, blinded experimental study.
The purpose of this study was to evaluate systematically the effects of the adenosine antagonist aminophylline on resuscitation outcome in a canine model of postcardioversion nonperfusing rhythm. ⋯ The results of this study suggest that aminophylline fails to improve the outcome of resuscitation from prolonged ventricular fibrillation. It does not reverse established electromechanical dissociation and may in fact increase the number of cardioversion applications required to terminate ventricular fibrillation. The rationale for conducting clinical trials with aminophylline during cardiopulmonary resuscitation is questionable.
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J. Am. Coll. Cardiol. · Jun 1994
Comparative StudyImproved hemodynamic function and mechanical efficiency in congestive heart failure with sodium dichloroacetate.
The purpose of this study was to determine whether sodium dichloroacetate improves hemodynamic performance and mechanical efficiency in congestive heart failure. ⋯ Dichloroacetate administration stimulates myocardial lactate consumption and improves left ventricular mechanical efficiency. Forward stroke volume and left ventricular minute work increase significantly, with a simultaneous reduction in myocardial oxygen consumption. Dobutamine administration results in similar hemodynamic improvements but with no change in left ventricular mechanical efficiency and with opposite effects on lactate metabolism. The opposing metabolic actions, yet similar hemodynamic responses, of dichloroacetate and dobutamine suggest that these agents may be complementary in the treatment of congestive heart failure.
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J. Am. Coll. Cardiol. · Jun 1994
Influence of pacing-induced myocardial ischemia on left atrial regurgitant jet: a transesophageal echocardiographic study.
We investigated the influence of pacing-induced myocardial ischemia on systolic regurgitant jet in the left atrium, using simultaneous transesophageal echocardiography and transesophageal atrial pacing. ⋯ Quantitative changes in geometry and function of the left ventricle caused by pacing-induced myocardial ischemia augments systolic regurgitant jet size. An increase in the jet during atrial pacing is associated with new or increased wall motion abnormalities, especially of the posterior wall. Pacing-induced anterior wall motion abnormalities appear not to be related directly to an increase in the jet.
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J. Am. Coll. Cardiol. · May 1994
Randomized Controlled Trial Comparative Study Clinical TrialEffect of beta-blockade on heart rate variability in patients with coronary artery disease.
This study assessed the effects of beta-blockade on heart rate variability in patients with coronary artery disease and determined whether the effects of metoprolol in a controlled-release formulation and atenolol differ with regard to electrocardiographic measures of cardiac autonomic control. ⋯ Beta-blockade by metoprolol and atenolol enhance the heart rate variability in patients with coronary artery disease. This may contribute to the protective effects of beta-blockade in ischemic heart disease.