In 78 (0.9%) of 8,283 patients without associated congenital heart disease studied by angiography, one or more major elements of the coronary arterial system originated in an ectopic manner. Symptoms attributable to the aberrant vessel more present in 20 of the 78 patients and in 15 patients these anomalies were treated surgically. The hemodynamically significant anomalies which lead to abnormalities of myocardial perfusion are of particular surgical importance. There are 4 major types: 1) aberrant origin of the left anterior descending branch from the pulmonary artery; 2) origin of the left coronary artery from the right aortic sinus; 3) origin of the left coronary artery from the pulmonary artery and 4) severe atherosclerotic occlusive disease in an aberrant vessel. The incidence, angiographic features and surgical aspects of these anomalies are discussed.
One hundred and seven patients with chronic heart failure (NYHA class II to IV) stabilized on digitalis and/or diuretics, recruited from 11 centres were randomized into a double-blind, placebo-controlled study to assess the effect of 12 weeks of cilazapril therapy on exercise tolerance and clinical status. Thirty-five patients were randomized to placebo and 72 to cilazapril at a starting dose of 1 mg daily; titration to cilazapril 2.5 mg at week 4 and 5 mg at week 8 (or matching placebo) was carried out in patients who did not improve clinically. Demographic characteristics, including exercise test duration increased from 402 s (+/- 17 SEM) at baseline to 462 s (+/- 19 SEM) at week 12 for the cilazapril group (+15%) and from 405 s (+/- 23 SEM) at baseline to 408 s (+/- 30 SEM) at week 12 in patients on placebo (+1%) (P < 0.001). In the placebo group, patients able to exercise for more than 6 min at baseline showed an increase in exercise duration at week 12 while those able to exercise for up to 6 min at baseline showed a decrease (P = ns). In contrast, cilazapril-treated patients showed an increase in exercise tolerance regardless of baseline exercise test duration; patients with the most impaired exercise tolerance at baseline showed a greater improvement than patients with mildly impaired baseline exercise tolerance (P < 0.05 vs placebo). NYHA class improved by at least one grade in 51% of the cilazapril group vs 32% in the placebo group (P = ns). At the end of the trial, 15% of the patients were non-responders on cilazapril vs 41% on placebo (P < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)
We have evaluated clinically a rate-responsive pacemaker which uses the evoked QT principle as indicator of physiological demand. This pacemaker is microprocessor-based and fully programmable noninvasively through radiofrequency coupling to an external microcomputer. To date this system has been implanted in 15 patients. With this QT sensing pacemaker the rate response to exercise was smooth and progressive, and gradually returned to the basic paced rate after termination of activity. Physiologic rate responsive pacing resulted in significant improvement in exercise tolerance and a 40% increase in cardiac output when compared to fixed-rate pacing in 8 patients. This initial experience confirms the possibility of obtaining a physiological response to exercise using a pacing system dependent only on a unipolar electrode which is independent of the problems of atrial activity and sensing. Rate responsive pacing might prove to be a useful alternative to atrial synchronous systems, and particularly advantageous in those patients whose sinoatrial function is abnormal or who suffer from atrial arrhythmias.
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