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We report the safety and feasibility of the first three patients using cardiopulmonary bypass support at the Indiana University Medical Center during PTCA. All patients had severe left ventricular dysfunction. Cannulation was performed using 18- or 20-French cannulae of the femoral vessels, either surgically or percutaneously. After heparinization with an activated clotting time of greater than 450 seconds, cardiopulmonary bypass was instituted using the Bard CPS system. Flows ranged from 3.0 to 4.3 L/min. Normasol was used to prime the pump. Blood was retransfused back into the patient at the end of the procedure. Bleeding was a problem in case 1 at the arterial cannulation site and subsequently was corrected for cases 2 and 3. Coronary angioplasties were deemed technically successful. We conclude that high-risk angioplasty can be performed in patients with poor left ventricular function using cardiopulmonary bypass support in the cardiac catheterization laboratory. Further study is indicated.

The recent application of exercise electrocardiography in asymptomatic populations requires the physician to be aware of the differences in sensitivity, specificity, and predictive value when compared with its application in the symptomatic population. Strict application of standard testing methodology is necessary to assure valid data collection and to permit the most meaningful interpretation. The prevalence of the false-positive electrocardiogram is distressingly frequent and often eventuates in further diagnostic testing. The asymptomatic positive ECG response does increase the risk of development of overt manifestations of ischemic heart disease. Routine testing in the asymptomatic population should be limited to high-risk population subsets.

The occurrence of ventricular arrhythmias at rest or during ordinary daily activities has been implicated as a risk factor for future coronary-related events and sudden death. However, the clerical significance of exercise-induced ventricular arrhythmias remains uncertain. To assess the prevalence and reproducibility of such arrhythmias, two serial maximal treadmill exercise tests were performed in a study population of 543 male Indian State policemen at an average interval of 2.9 years. Four hundred sixty-two subjects were clinically free of evidence of cardiovascular disease, and 81 had evidence of definite or suspected cardiovascular disease. The prevalence of exercise-induced ventricular arrhythmias during the first test was 30% in men aged 25 to 34 years, 32% in those aged 35 to 44 years and 36% in those aged 45 to 54 years. The prevalence rate in these age groups with repeat testing was 36, 38 and 42%, respectively. These differences were not statistically significant. The group with definite or suspected cardiovascular disease had a greater prevalence of exercise-induced ventricular arrhythmias than normal subjects during both tests but the prevalence rate with repeat testing remained constant. The occurrence of exercise-induced ventricular arrhythmias was reproducible in individual subjects during the second test in 55% of 25 to 34 year olds, 58% of 35 to 44 year olds and 62% of 45 to 54 year olds. Thus, individual reproducibility in two consecutive tests was only slightly greater than reproducibility by chance alone. The group with known or suspected cardiovascular disease demonstrated a trend toward greater reproducibility with repeat testing. Exercise-induced ventricular arrhythmias were not reproducible by type or complexity. The marked variability of exercise-induced ventricular arrhythmias during repeat maximal exercise testing in a clinically normal population appears to negate the usefulness of this finding during a single test as a marker of future cardiovascular disease. Nevertheless, subjects whose arrhythmias were reproducible may form a group destined to manifest clinical cardiovascular disease in long-term follow-up studies.

The echocardiographic features of mitral valvular motion in a patient with classic rheumatic mitral stenosis are presented. Two unusual features were noted, and the important of careful echocardiographic scanning of the mitral valve is imphasized. The theories for the classic echocardiographic abnormalities of mitral stenosis are briefly considered in light of the findings in this case.

A ventilation-perfusion (V/Q) lung scan in a postoperative patient with a Swan-Ganz catheter showed an area of mismatch suggesting pulmonary embolism. Radiographs, as well as failure to get a venous return from the catheter suggested wedging. A pulmonary angiogram, performed after the Swan-Ganz catheter was pulled back, was essentially normal. An autopsy performed within 24 hours of the lung scan did not reveal pulmonary emboli. Wedged Swan-Ganz catheter was probably responsible for the V/Q mismatch.

Maximal treadmill exercise tests were performed by 586 male members of the Indiana State Polic Force who were free of clinical evidence of cardiovascular disease. The study population was categorized into groups according to cigarette smoking experience and subgroups according to age and number of pack-years of exposure. There were 176 nonsmokers (30 percent), 268 current smokers (46 percent) and 142 former smokers who had abstained for at least 1 year (24 percent). No statistically significant differences were found in the prevalence of exercise-induced ventricular premature complexes when current smokers were compared with nonsmokers or former smokers either as a group or as subgroups classified by age. The duration of maximal exercise and the peak heart rate and systolic blood pressure during maximal exercise were compared for each group. The duration of maximal exercise was significantly shorter in smokers (P less than 0.001) and former smokers (P less than 0.005) than in nonsmokers. Maximal systolic blood pressure during exercise was greater in smokers than in nonsmokers (P less than 0.01) but did not differ significantly between nonsmokers and former smokers. Maximal heart rate during exercise was significantly lower in smokers (P less than 0.01) and former smokers (P less than 0.01) than in nonsmokers. In conclusion, there was a statistically significant difference in the duration of exercise and the maximal heart rate and systolic blood pressure attained during exercise between men who smoked and nonsmokers, but the prevalence of the exercise-induced ventricular premature complexes did not appear to be influenced by smoking habits.

Exercise and 3 hour delayed redistribution thallium-201 myocardial perfusion imaging was performed in 107 patients including 87 patients with documented coronary artery disease and 20 patients with normal coronary arteriograms. A computer algorithm for statistical analysis and redisplay of the analog scintillation data was developed to augment the visual analysis of the standard analog image. The basic algorithm identified the myocardial area (pixel) with the most absolute counts and developed an appropriate standard deviation range from a table. All pixels in the area of the myocardium containing absolute counts below three standard deviation ranges (or approximately 6 standard deviations) were deleted from the final image. The remaining pixels were redisplayed in a digitized bimodal format and the image photographed. Two experienced observers compared visual analysis of the analog image alone and the analog image in conjunction with the computer-analyzed image for sensitivity, specificity and predictive accuracy in the detection of perfusion defects in patients with coronary artery disease and in normal subjects. Sensitivity in patients with coronary artery disease and in normal subjects. Sensitivity in patients with coronary artery disease for the analog scintillation image alone was 79 percent (69 of 87) and with computer analysis 95 percent (83 of 87). Specificity in the patients with no coronary disease was 100 percent (20 of 20) for both techniques. The predictive accuracy of the test was 83 percent (89 of 107) for the analog image alone and 96 percent (103 of 107) for the two images combined. It is concluded that use of a computer statistical analysis algorithm of thallium-201 analog myocardial perfusion images improves the accuracy of detection of perfusion defects in patients with coronary artery disease.

A 57 year old women with substernal nonexertional chest pain and angiographically patent coronary arteries was evaluated with two dimensional echocardiography and myocardial perfusion scintigraphy after provocation of pain with methacholine. Simultaneous with the development of angina pectoris, the electrocardiogram demonstrated S-T segment elevation in leads II, III and aVF, followed by atrioventricular block. The echocardiogram revealed akinesia of the previously normally contracting left ventricular posterior wall during pain followed by hyperkinesia after the administration of nitroglycerin. Perfusion imaging suggested reversible inferior wall hypoperfusion. Thus, these studies provided noninvasive documentation of segmental left ventricular dysfunction and hypoperfusion during variant angina.