Medical versus surgical treatment for angina pectoris

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Abstracts

stellate (RS) stimulation resulted in increased positivity of the T wave and prolongation of the Q-T interval. In 19 of 26 animals, left stellate (LS) stimulation resulted in decreased amplitude or negativity of the T wave. Unilateral RS or LS ablation caused various ECG changes generally characterized by lower amplitude, diphasic T waves and prolonged Q-T interval. These findings differ from previous findings in the dog. FRP’s were then measured at 8 epicardial sites in 5 animals before and after stellectomy. Right stellectomy prolonged FRP on the anterior right ventricular surface, and left stellectomy had a similar effect on the lateral and inferior left ventricular surface. This lateralization of stellate influence is common to dog and cat, but the areas of distribution are somewhat different. This finding, along with extrinsic factors such as body size and shape, may account for the species difference in ECG changes following unilateral alteration in sympathetic tone. Warming the anterior surface of the cat heart was then carried out in 5 animals with expectation of shortening recovery time in the area of suggested RS predominance. This resulted in ECG effects similar to those of RS stimulation. These findings demonstrate lateralization of stellate-induced FRP and ECG changes in the cat. Since stereotaxic mapping has been developed for the cat, this species appears suitable for the study of CNS-induced ECG changes. Acute Hemodynamic Effects of Red Cell Phoresis in Secondary Polycythemia with Cyanotic Congenital Heart Disease. A. ROSENTHAL,M.D., L. N. BURTON, B.S., A. T. MARTY, M.D., D. G. NATHAN, M.D. and A. S. NADAS,M.D., Boston, Mass. To investigate the hemodynamic effects of acute red cell mass reduction in cyanotic heart disease, 14 patients aged 31/2to 24 years were studied at catheterization prior to and following red cell phoresis of 18.9% (7.8-29.3) of the red cell volume (RCV) with fresh frozen plasma replacement. Measurements of RCV with 510, plasma volume (PV) with 1251, hematocrit (hct), arterial (A) and venous (V) blood gases, oxygen saturation and carrying capacity ‘VO,, cardiac output (CO), systemic resistance (SR), and in 3 instances blood viscosity were obtained prior to and after the procedure. Hypervolemia was present and constant in each individual. The initial mean hct of 73% (63-85) was lowered to 61% (53-65) and the carrying capacity from 28.7 (21.7-31.1) to 23.5 vol. % (16.1-28.4). CO increased from a mean of 3.5 +1.3 to 5.8 ? 2.5 L./min./M.2 (p < 0.05) and was

associated with a drop in SR from 26 2 9.7 to 15 f 5 units (1, < O.OOl), a small decrease in mean arterial pressure, decreased blood viscosity and yield shear stress (0.103-0.036 dynes/cm.2 at 38’ C.). Despite the fall in carrying capacity and (‘4) oxygen saturation, which was particularly observed in the patients with a diminished pulmonary blood flow, systemic oxygen transport (ml. of O,/min./kg.) increased from 27.3 1 8.3 to 35.9 -C 10.3 (0 < 0.05). Tissue perfusion improved with a rise in arterial pH from 7.346 2 0.029 to 7.382 & 0.037 (0 < 0.05). These results show that oxygen transport and tissue perfusion are improved by an acute reduction of RCV in cyanotic congenital heart disease. Medical Versus Surgical Treatment for Angina Pectoris. H. I. RUSSEK, M.D., F.A.C.C. and B. L. ZOHMAN,M.D., F.A.c.c., New York, N. Y. Results obtained after surgical revascularization of the myocardium were compared with those obtained after propranolol-nitrate therapy. Both groups of patients were strikingly similar in age, sex, severity of angina pectoris, duration of disease and cineangiographic findings. The medically treated group showed a higher percentage of complicating disease. In 86 patients in whom single or double arterial transplants were performed, there was an immediate mortality of 24.4% and a delayed mortality (during the first 6 months) of 8.1%. Triple coronary artery disease, present in 30 surgically treated patients, was associated with an immediate mortality of 40% and a delayed mortality of an additional 10%. Only 32 of the 86 cases (37.2%) showed unequivocal clinical improvement. Major postoperative complications developed in 17 instances. In the medically treated group of 52 patients, the total mortality rate was 7.6y0 during the first year of therapy, and 95.5% of those treated showed excellent clinical response. The differences between the results of medical and surgical therapy are highly significant statistically (@ < 0.001). These results indicate the need for careful reassessment of the indications for surgical intervention. At present propranolol-nitrate therapy appears to offer far less risk and considerably greater clinical benefit in the first year of follow-up study. Left Ventricular Power in Heart Disease. R. 0. RUSSELL, JR.,M.D., F.A.c.c., M. FRIMER, B.s.E.E., C. hl. PORTER, nr.~. and H. T. DODGE, M.D., F.A.c.c., Birmingham, Ala. Left ventricular (LV) power (P x dV/dt) was calculated from LV volume curves determined THE

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OF CARDIOLOGY