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Clinical and angiographic features of 31 patients with anomalous coronpary artery origin are reviewed. Of 17 aberrant circumflex arteries from the right sinus of Valsalva or artery, each was retro-aortic, six atherosclerotic, and seven irrigated a small area of myocardium. Of seven anomalous right coronary arteries from the left sinus of Valsalva or artery, each was ante-aortic and two atherosclerotic. Aberrant origin of the circumflex or right coronary artery was a benign anomaly. The proximal course of seven aberrant left coronary arteries from the right sinus of Valsalva or right coronary artery was related to clinical events. The anomaly was best demonstrated in the lateral view. In five cases, coronary blood flow during exercise and myocardial metabolism during pacing were assessed. Two had had a previous infarction with nonatherosclerotic arteries. Exercise coronary blood flow was normal in four and low in one patient. Pacing resulted in lactate production in two with atherosclerotic and one without atherosclerotic arteries. We conclude that anomalous left coronpary origin from the right sinus of Valsalva can result in significant myocardial ischemia and infarction.

The cardiac profile of 38 patients readmitted to the hospital with the clinical and radiologic findings of pulmonary artery hypertension and right ventricular failure 2 months after ingestion of toxic rapeseed oil was determined with M-mode and two-dimensional echocardiography, pulsed Doppler flow studies and right and left heart catheterization and ventriculography. The echocardiogram and pulsed Doppler recordings revealed right ventricular enlargement in 84% of the patients, indirect evidence of pulmonary artery hypertension in 76% and tricuspid insufficiency in 13%. At cardiac catheterization (n = 11) the mean (+/- standard deviation) pulmonary artery pressure was 40 +/- 9 mm Hg, mean pulmonary systemic vascular resistance ratio was 0.45 +/- 0.12 and mean right ventricular end-diastolic pressure was 13 +/- 4 mm Hg. Pulmonary artery hypertension was sustained after the acute administration of 100% oxygen and persisted in six patients who were restudied within 6 months. Cardiac index and left heart pressures were normal in all but one patient. The contrast ventriculographic studies revealed right ventricular dilation in all patients, tricuspid regurgitation in three patients and a normal left ventricular contraction pattern in all but one patient. The data confirm that symptomatic pulmonary artery hypertension and associated right ventricular dysfunction can complicate toxic rapeseed oil ingestion and that these findings persist for at least 6 months.

Medical certification to return to work after coronary bypass surgery in occupations that carry a risk to public safety is controversial, particularly for airline pilots. To address this issue, 10,312 patients from the CASS registry who underwent coronary bypass surgery were studied and 2,326 men with clinical and postoperative characteristics similar to those of the average airline pilot who might apply to renew his license after surgery were selected. The 5 year probability of remaining free of an acute cardiac event, defined as acute coronary insufficiency, myocardial infarction or sudden death, was 0.92 +/- 0.01 (mean +/- SE) for the 1,207 men without previous myocardial infarction and 0.98 +/- 0.01 for the 122 men who never smoked and did not have a history of hypertension. Among the 1,119 men with a previous myocardial infarction, the probability of remaining free of acute cardiac events was 0.91 +/- 0.02 and 0.92 +/- 0.02 when left ventricular contraction score was 5 to 9 and 10 or greater, respectively. In this patient subgroup, mortality rate was similar to that of the age-matched U.S. male population when the left ventricular contraction score was 5 to 9 (4.0% versus 4.3%; p = NS) but significantly worse when the left ventricular contraction score was 10 or greater (7% versus 4.2%; p = 0.05). The data from this CASS registry study are pertinent to the question of operationally unlimited first-class medical certification of carefully selected airline pilots after coronary bypass surgery.(ABSTRACT TRUNCATED AT 250 WORDS)

Baseline, clinical, and angiographic features of 1014 Coronary Artery Surgery Study (CASS) registry patients with combined proximal left anterior descending and proximal left circumflex coronary disease were examined to define determinants of prognosis in this clinical high-risk patient subset. A stepwise Cox regression analysis identified congestive heart failure score, left ventricular contraction score, mitral regurgitation, age, and digitalis usage as independent variables predictive of 8-year survival. When patients were stratified by left ventricular contraction score, the 8-year survival rate was 62%, 49%, and 19%, respectively, for patients with a left ventricular score of 5 to 9, 10 to 14, and greater than or equal to 15 (p less than 0.0001). The presence of a stenosis greater than or equal to 70% in the right coronary artery was associated with worse survival (47% versus 54% at 8 years; p = 0.051). In conclusion, the diagnosis of combined proximal left anterior descending and left circumflex coronary artery disease represents a large prognostic spectrum that needs to be considered when counselling individual patients.

Between January 1970 and July 1978, 85 patients aged 65 years or more underwent aortocoronary bypass surgery at the Montreal Heart Institute. The mortality during the operation and the first 29 days thereafter was 12% overall, but was only 5% when the myocardium was protected by the use of cold cardioplegic solutions. Of the 75 patients who survived this period 7 (9%) had a perioperative transmural myocardial infarction. Nonfatal noncardiac complications were more common in these patients than in younger patients, but did not lead to permanent deficits. Three patients died after discharge from hospital, two of cardiac causes. Only one patient had a nonfatal myocardial infarction after discharge. The actuarial 5-year survival rate for all the patients was 80%. After a mean follow-up period of 30 months the condition of 94% of the patients was improved by at least one class of the New York Heart Association functional classification, and 68% were asymptomatic. It is concluded that aortocoronary bypass surgery can be performed in selected older patients with a relatively low in-hospital mortality and morbidity. Symptomatic improvement occurs in almost all such patients. Cardiac catheterization and aortocoronary bypass surgery should therefore be performed in selected older patients with severe angina that is refractory to optimum medical therapy.

Laser recanalization of occluded femoral or popliteal arteries was performed in 12 patients using a continuous wave neodymium yttrium aluminum garnet (Nd-YAG) laser. The histologic findings of the laser-irradiated arterial segments in two of these patients are reported. The specimens were obtained 2 and 4 weeks after the laser procedure. The laser-irradiated vessel in Patient 1 had been partially recanalized with reduction of the atherosclerotic occlusion from 3 to 1 cm. The lased arterial lumen manifested thermal injury to the inner quarter of the arterial wall with vacuolization and a rim of carbonization occupying 10% of the width of the arterial wall, but without thrombus formation. Histologic examination in Patient 2 revealed no fibrin deposits, atherosclerotic debris or thrombi at the intimal arterial edge. At the crater site, thermal injury was apparent with vacuolization of the intimal fibrous tissue. The histologic sections obtained 4 weeks after the procedure revealed new fibrous intimal tissue without endothelialization in some of the heavily calcified tissue sections. Where the plaques were noncalcified, reendothelialization was noted with only minimal damage to the surrounding tissue. No medial or elastic fiber disruption was seen, and no aneurysmal dilation had occurred. Intimal splitting with a cleft between the tunica media and the intima was noted at the site of previous balloon angioplasty. In conclusion, the follow-up histologic findings 2 and 4 weeks after laser angioplasty in two patients using a specially designed catheter delivery system and cooling blood perfusate revealed thermal injury to the inner quarter of the arterial vessel wall and no evidence of thrombus formation.

Thallium perfusion imaging following the intravenous infusion of dipyridamole, a potent coronary vasodilator, has been demonstrated to be useful in the evaluation of the functional significance of coronary artery disease (CAD). While recent studies have demonstrated that 2-dimensional echocardiographic monitoring of left ventricular (LV) function after intravenous dipyridamole has a sensitivity somewhat less than that of thallium perfusion imaging, none has examined the usefulness of Doppler evaluation of aortic blood flow in this setting. One hundred patients undergoing dipyridamole-thallium imaging for clinical indications were studied. Technically adequate Doppler echocardiographic studies were obtained in 97 patients. LV ejection fraction, peak aortic velocity and acceleration, as well as segmental LV wall motion, were analyzed before and at peak dipyridamole effect. Thallium perfusion images were normal in 41 and abnormal in 53 patients studied. A statistically significant difference in percent change from baseline to peak dipyridamole effect in velocity, acceleration and ejection fraction was seen between the 2 groups (26 vs -2%, 51 vs -2% and 16 vs 4%, respectively, all p less than 0.05). Comparison of 2-dimensional wall motion analysis to thallium yielded a sensitivity and specificity of 74 and 80%, respectively. In the group of patients who underwent cardiac catheterization, 2-dimensional wall motion analysis yielded a sensitivity of 64% in the detection of CAD. The combination of 2-dimensional and Doppler echocardiographic parameters increased the sensitivity in the detection of CAD to 85%.(ABSTRACT TRUNCATED AT 250 WORDS)

Most patients who are considered candidates for coronary angioplasty should have objective evidence of myocardial ischemia confirmed before the procedure, if clinically possible. In patients with progressive unstable angina, for whom exercise testing is inappropriate, the location of transient resting ECG changes should be looked for on the 12-lead ECG. In clinically stable patients with 1-vessel coronary disease, a pre-PTCA exercise test without radionuclides would suffice for most patients. In the initial months after PTCA, persistence or the return of an ischemic response similar to that observed before the procedure would indicate restenosis. Disease progression in other vessels during the year after the PTCA procedure would be uncommon compared to the incidence of restenosis. In all other stable patients, exercise ECG should be combined with thallium-201 scintigraphy to provide a more useful evaluation of angioplasty results. If only a single vessel is dilated, the importance of the remaining coronary disease may be demonstrated and may influence the clinical decision as to whether further intervention is needed. Dilatation of occluded vessels is occasionally attempted in patients with multivessel coronary disease. The incidence of restenosis is slightly greater (40%) in the months after PTCA than in a stenotic nonoccluded vessel. Multilesion dilatation can also be associated with restenosis at more than one site, and the use of thallium scintigraphy may be helpful in assessing which region of the myocardium is ischemic. As dilatation is performed more frequently in patients with multivessel disease, coronary angiography will remain the 'gold standard' to answer questions about recurrence or progression of the disease, and against which to compare results of noninvasive tests. All exercise tests should be performed without cardioactive medication if possible, and the test should be a sign- or symptom-limited test. The elective exercise test in an asymptomatic individual after PTCA should be performed between 1 and 2 weeks to serve as a baseline for future follow-up. In patients who develop restenosis, symptomatic status will often suggest a PTCA failure. In asymptomatic patients or those with atypical symptoms, the exercise thallium study will often be useful.

To evaluate the significance of ischemic ST-segment depression without associated chest pain during exercise testing, data were analyzed from 2,982 patients from the Coronary Artery Surgery Study (CASS) registry who underwent coronary arteriography and exercise testing and were followed up for 7 years. Patients with proved coronary artery disease (CAD) (at least 70% diameter narrowing) were grouped according to whether they had at least 1 mm of ST-segment depression or anginal chest pain during exercise testing. Four hundred twenty-four had ischemic ST depression without angina (group 1); 232 had angina but no ischemic ST depression (group 2); 456 had both ischemic ST depression and angina (group 3); and 471 had neither ischemic ST depression nor angina (group 4). Sixty-three percent of patients in group 1 and 55% in group 2 had multivessel CAD (difference not significant). The 7-year survival rates were similar for patients in groups 1 (76%), 2 (77%), and 3 (78%), but were significantly better for patients in group 4 (88%, p less than 0.001). Among group 1 patients, survival was related to severity of CAD (p less than 0.001). The 7-year survival rate in group 1 was significantly worse than that in a separate group of 282 patients with ischemic ST depression without angina during exercise testing who had no CAD (95% survival, p less than 0.001). Thus, in patients with silent myocardial ischemia during exercise testing, the extent of CAD and the 7-year survival rate are similar to those of patients with angina during exercise testing. Prognosis is determined primarily by the severity of CAD. In patients without CAD, the survival rate is excellent.

The duration of electrical systole (QT interval) was measured in 72 subjects (48 women and 24 men) who had normal coronary arteries and left ventricular function at cardiac catheterization (group 1). The same measurements were obtained in 100 patients with a normal ECG (from 40 women and 60 men referred to our institution and found normal on a noninvasive clinical basis) and compared to a double independent manual calculation (group 2). The computer assisted program was found reliable in QT interval measurements. In both study groups women showed longer QTc. No difference in QTc duration was seen in subjects taking beta-blockers prior to angiography. As compared to group 1, subjects of group 2 showed similar average QTc values. However, 9 out of 100 subjects of group 2 had abnormal QTc as compared with none of group 1 (p less than 0.05). QTc calculations may improve the usefulness of computer assisted programs in ECG interpretation. Present data can be used as reference values for normality. They stress in addition the necessity of introducing the heart rate correction for the interpretation of QT interval. This can help in stimulating prospective clinical studies to assess the value of QTc as an index of risk for cardiac dysrhythmias.

The diagnostic accuracy of 14-lead exercise electrocardiography was evaluated in 112 women who had no history of myocardial infarction and underwent coronary angiography. The sensitivity of ST-segment displacement of 0.1 mV or more in any of 14 ECG leads was 0.79 for coronary artery stenosis of at least 70%; the specificity was 0.66. Results were similar using bipolar ECG leads CC5 and CM5 or 11 standard ECG leads. The ST-segment shifts that occurred only during exercise were associated with a 77% false-positive rate (10 of 13). Downsloping ST-segment depression did not provide more diagnostic information than horizontal ST-segment depression in the three clinical subsets of women. In women with typical angina pectoris, ST-segment depression of at least 0.15 mV for 0.08 second after the J point or a final treadmill time less than 360 seconds was predictive of proximal left or multivessel coronary artery disease. In the women with probable angina or nonspecific chest pain, this finding was not of diagnostic value. ST-segment elevation of 0.1 mV or more in leads V1-2 or a VL predicted proximal stenosis of at lest 80% in the left anterior descending coronary artery in all six women with typical angina pectoris. Maximal exercise testing in women with typical angina provides important diagnostic information when 11 standard ECG leads are recorded. In women with probable angina or nonspecific chest pain, diagnostic exercise testing is less useful and bipolar leads CC5 and CM5 are sufficient for most clinical purposes.

Physiological adaptations of the heart to prolonged, intense physical training produce electrocardiographic changes considered abnormal in untrained persons. Increased vagal tone, anatomical changes in the heart, and other less understood mechanisms are thought to cause a spectrum of surface ECG changes characteristic of trained athletes. Arrhythmias frequently seen include sinus bradycardia, sinus pauses, and supraventricular ectopic beats. Conduction abnormalities such as prolonged P-R interval, first degree AV heart block, Wenckebach type I AV heart block, non-sinus escape rhythms, and intraventricular conduction delays of right bundle branch type are also found. Other commonly seen abnormalities include right axis deviation, increased right and left ventricular voltage, ST segment elevation, diphasic and inverted T waves, and prominent U waves. Changes in ECG parameters with exercise include a shortening of the P-R interval with a concomitant increase in the P wave/P-R interval ratio, improved AV conduction with cessation of Wenckebach phenomenon, and normalisation of ST segment and other T wave changes. Thallium scintigraphy and radionuclide angiography have been very useful in ruling out ischaemic heart disease in athletes with rest- and exercise-induced repolarisation abnormalities. Racial differences in QRS voltage and repolarisation changes have been documented. In summary, it is important to consider the type of physical activity, intensity of training, race of athlete, body habitus, and the time the ECG was obtained in relation to training in order to better understand the "normal' spectrum of ECG changes in athletes.

Of 99 patients who underwent "emergency" diagnostic studies, 82 had "unstable angina" (group A), 15 had recent myocardial infarction (group B), and two had intractable congestive heart failure due to acute mitral regurgitation (group C). Two cardiac and two local complications occurred either during the procedure or during the following 48 hours. There were no deaths or myocardial infarctions. Ten (12 percent) patients of group A had "normal" coronary arteries and normal left ventricular function; 13, 26 and 33 patients had one, two, and three coronary arteries involved, respectively. Those with three-vessel disease had a significantly higher left ventricular end-diastolic pressure (LVEDP) and lower ejection fraction (EF) than those with one- and two-vessel disease. Those with previous myocardial infarction had a significantly higher incidence of reduced EF and of wall motion abnormalities than those without a previous myocardial infarction. All patients in group B had significant coronary arterial disease, and 80 percent (12) had abnormal left ventricular function. Their mean LVEDP and EF were significantly higher and lower, respectively, than those found in group A. In conclusion, acutely ill patients were studied with low risk. Most patients had three- or two-vessel disease. Abnormal left ventricular function was related to three-vessel disease and to recent and old myocardial infarction.

The acute antianginal effects of 5 mg and 20 mg nisoldipine were compared with 20 mg nifedipine and placebo. Maximal treadmill exercise testing was performed before and 3 hours after drug administration in 10 patients with chronic stable angina. Resting heart rate and systolic blood pressure were unchanged following low-dose nisoldipine, but 20 mg nisoldipine and 20 mg nifedipine increased heart rate and decreased systolic arterial pressure (p less than 0.05). Time (in seconds) to the onset of 0.1 mV ST segment depression was significantly prolonged after 5 mg nisoldipine (+60 +/- 53; p less than 0.05) and 20 mg nisoldipine (+100 +/- 78; p less than 0.01) but not after 20 mg nifedipine (+48 +/- 131; p = NS). Total exercise duration increased significantly following 5 mg and 20 mg nisoldipine (p less than 0.01 and p less than 0.001, respectively) but only slightly following nifedipine (p = NS). The maximal rate-pressure product was increased to a similar degree following doses of both nisoldipine and nifedipine (p less than 0.05). Nisoldipine is an effective antianginal agent which performs well in comparison to nifedipine.

Diltiazem is a calcium slow-channel blocking drug that may be effective in the treatment of chronic stable angina pectoris. To evaluate the therapeutic efficacy 3 hours after a single oral dose of 120 mg, 12 men with chronic stable angina pectoris performed a maximal exercise test on a bicycle ergometer after ingesting either placebo or diltiazem administered in a double-blind fashion. During submaximal exercise at a fixed work load, diltiazem decreased the average heart rate response from 119 +/- 17 to 107 +/- 14 beats/min (p less than 0.01), systolic blood pressure from 182 +/- 15 to 175 +/- 15 mm Hg (p less than 0.05) and the rate-pressure product from 21.8 +/- 4.2 to 18.8 +/- 3.2 x 10(-3) units (p less than 0.01). The average submaximal work load at which significant ST-segment depression (0.1 mV) first appeared was increased from 355 +/- 142 to 525 +/- 143 seconds (p less than 0.01) after diltiazem. At peak exercise after diltiazem, the average depth of ST-segment depression in any one lead and the extent of myocardial ischemia observed in all 12 ECG leads were decreased (p less than 0.01), even though the average work load was increased by 29% (p less than 0.01). Peak heart rate, systolic blood pressure and rate-pressure product were similar with placebo and diltiazem. The plasma diltiazem concentration was 13.9 +/- 29 ng/ml 3 hours after ingestion and was significantly (p less than 0.05) related to the increased time to the onset of important ST-segment depression (r = 0.65) and to the decrease in the extent of myocardial ischemia observed in all 12 ECG leads (r = -0.61) compared with placebo. Thus, diltiazem is effective in treating chronic stable angina pectoris. It decreases myocardial oxygen requirements during upright exercise and appears to increase myocardial oxygen delivery.

Left ventricular performance, coronary anatomy and postoperative clinical parameters of 66 control patients (group 1) randomly selected from 797 survivors of coronary bypass surgery were compared with those of 45 patients who died within 30 days of operation (group II) and 53 patients who died late (average, 22+/-2 mo) (group III). Average preoperative left ventricular end-diastolic pressure, ejection fraction and mean circumferential fibre shortening rate were significantly better in group I than in group III patients. These same parameters were not significantly different when group I was compared to group II. Abnormal wall motion was significantly less frequent in patients from group I than in patients from group II and III. Triple-vessel disease was present preoperatively in 40 (61%) controls compared with 37 (82%) early deaths (P = 0.021) and 35 (66%) late deaths (NS). The number of grafts placed per patient was not significantly different in the three groups. Perioperative myocardial in farction (MI) and low cardiac output syndrome were the commonest causes of early death. Late complications such as MI and heart failure occurred in 4 (6%) v; 15 (32%) (P = 0.0006) and 4 (6%) v. 27 (57%) (Pless than 0.0001) group I v. group III patients, respectively. Surgical expertise, preoperative ventricular performance and triple-vessel disease are important determinants of early mortality following bypass surgery and preoperative left ventricular performance is one of the most important determinants of late mortality,

Carpentier-Edwards bioprostheses were implanted in 605 patients, 509 of whom had a single valve replacement, and 96 of whom had a multiple valve replacement. There were 54 early deaths (8.9%) and 26 late deaths (4.3%). The five-year actuarial survival was 87% for aortic valve replacement, 83% for mitral valve replacement, and 81% for multiple valve replacement. Of the 525 survivors, all but 3 were followed for a total of 964 patient-years; 354 patients (68%) remained asymptomatic, and 95 patients (18%) were improved. The incidence of thromboembolism, endocarditis, and reoperation due to primary tissue failure of the bioprosthesis were 2.0, 1.3, and 0.1% per patient-year, respectively. The actuarial probability of being free of all valve-related complications was 93% after five years. Satisfactory hemodynamic performance of the bioprosthesis was demonstrated by postoperative studies done in 70 patients. Thus, the Carpentier-Edwards porcine valve provides good clinical improvement, with a low incidence of valve-related complications and tissue failure at five years postoperatively.

Recent advances in Doppler echocardiography have made possible noninvasive determination of stroke volume, cardiac output and peak ejection velocity at rest. To determine the ability of Doppler to measure these variables and the effect of altered left ventricular (LV) function during upright treadmill exercise, 20 normal subjects (group I) and 17 patients with coronary artery disease (CAD) (group II) were studied. Stroke index response was similar in both groups. The increase in cardiac index was more rapid in group I subjects and reached a higher peak value at maximal exercise (8.6 +/- 2.5 vs 5.5 +/- 2.2 liters/min, p less than 0.001). Peak ejection velocity increased rapidly during exercise in group I subjects; it increased much less in group II patients. Differences were significant at each stage of exercise. Peak ejection velocity was 1.56 +/- 0.32 and 0.89 +/- 0.26 m/s in group I vs group II patients, respectively, at maximal exercise. Three responses were seen in group II subjects. Three patients, all with 1-vessel CAD and normal LV function at rest, showed a normal response, with an increase in peak ejection velocity of at least 80% (type I response). In 8 patients peak ejection velocity increased less than 80% (type II response) and in 6 patients it decreased at maximal exercise (type III). Type II and III responses were seen in patients with more severe CAD and LV dysfunction at rest. These data show a progressive difference in Doppler-derived variables in exercise between normal subjects and patients with CAD, which is greatest in patients with LV dysfunction at rest and multivessel CAD.

Between September 1966 and September 1976, a group of 48 patients with normal coronary arteries or nonsignificant coronary atherosclerosis documented in a first coronary arteriogram underwent a second angiogram because of persistent or recurrent chest pain. The interval between studies was 13 to 108 months (mean 42 months). The indication for the first angiogram was typical or atypical anginal pain. The patients were separated into two groups according to the results of the first angiogram. Group I included 22 patients, 9 men and 13 women, with normal coronary arteries (mean age 49 years, range 28 to 62). Group II included 26 patients, 18 men and 8 women, with coronary stenosis of less than 50% of intraluminal diameter (mean age 49 years, range 38 to 63). The second angiogram revealed normal coronary arteries in all 22 patients in Group I but showed progression of diseases in 7 (27%) of the 26 patients in group II. The coronary arterial narrowings were greater than 50% in four patients and greater than 70% in only two patients. The clinical course, coronary risk factors and interval between angiograms were not useful predictors of progression of disease. The data suggest that coronary artery disease is unlikely to developed in adults with normal coronary arteries and that roughly 75% of adults with nonsignificant atherosclerosis will not show progression of disease over a 3 to 4 year period.

Isolated junctional S-T depression induced during treadmill exercise testing was correlated with coronary arteriographic findings in 230 patients. Of 75 patients with junctional depression of less than 1.5 mm, 10 had 50% or greater stenosis of at least one major coronary artery and 2 patients (3%) had multivessel disease. Of 42 with junctional depression of 1.5 mm or more and a rapid upsloping S-T segment, 23 had 50% or greater coronary stenosis and 12 of these had multivessel disease. Of 35 with an upsloping pattern (junctional depression of more than 2 mm, upsloping S-T segment depressed 2 mm or more, 0.08 second after the J point), 33 (94%) had 50% or greater coronary stenosis compared with 46 (96%) and 30 (97%) with 2 mm or more junctional depression ahd a horizontal or downsloping S-T segment. In conclusion, multivessel disease is rare with isolated exercise-induced junctional depression of less than 1.5 mm but common when the J point is depressed 1.5 mm or more. Junctional depression of more than 2 mm is associated with the same incidence of coronary disease when the S-T segment is slowly ascending (upsloping pattern) as when it is horizontal.

To identify predictors of mortality in medically treated patients with symptomatic coronary artery disease, 30 variables were analyzed in 4,083 patients. Regression analysis demonstrated that seven variables were independent predictors of survival. A high risk subgroup (annual mortality rate above 5%) was identified, consisting of patients with either a congestive heart failure score of 3 to 4 or 1 mm or greater ST segment depression and final exercise stage of 1 or less. When all 30 variables were analyzed conjointly, the left ventricular contraction pattern (p less than 0.0001) and the number of diseased coronary vessels (p less than 0.003) proved to be the most important predictors of survival. In a subgroup of 572 patients with three vessel coronary disease and preserved left ventricular function, the probability of survival at 4 years ranged from 53% for patients only able to achieve stage 1/2 of exercise to 100% for patients able to exercise into stage 5 (p less than 0.004). Thus, in patients with defined coronary pathoanatomy, clinical and exercise variables primarily relating to the functional state of the left ventricle are helpful in assessing prognosis.

The Angell-Shiley porcine xenograft was evaluated in 48 asymptomatic subjects who underwent cardiac catheterization an average of 14 months after operation. Nineteen patients had mitral and 29 had aortic valve replacement. The average mitral valve gradient was 8 +/- 3 mm Hg and the average effective orifice area was 1.8 +/- 0.6 cm2. The average aortic valve gradient was 22 +/- 7 mm Hg and the average effective orifice area was 1.2 +/- 0.3 cm2. During supine leg exercise, the average mitral valve gradient increased to 12 +/- 4 mm Hg (p less than 0.001) and the average aortic valve gradient increased to 27 +/- 8 mm Hg (p less than 0.001) compared to findings at rest. On the basis of data obtained with a regression analysis model, there is a high probability that an Angell-Shiley aortic xenograft with a stent diameter less than 25 mm will have a postoperative effective orifice area of less than 1 cm2, and that an Angell-Shiley mitral xenograft with a stent diameter less than 30 mm will have a postoperative effective orifice area of less than 1.5 cm2. Our data suggest that the Angell-Shiley xenograft has suboptimal hemodynamic performance in stent sizes less than 30 mm in the mitral position and less than 25 mm in the aortic position.

The acute effect of a single oral 100 mg dose of ibopamine on systolic and diastolic left ventricular function in nine patients with congestive heart failure was assessed by quantitative M-mode and pulsed Doppler echocardiography. Echocardiography was performed at baseline and 30, 60, and 120 minutes after ingestion of drug. Indices of systolic and diastolic left ventricular function were derived from digitized tracings of the septal and posterior endocardial surfaces and transmitral and aortic valve velocity profiles. Ibopamine significantly improved systolic function as reflected by a decrease in the preejection period to left ventricular ejection time ratio from 0.57 +/- 0.16 at baseline to 0.47 +/- 0.15 (p less than 0.05) 30 minutes after ingestion of drug. The maximum improvements in stroke volume and cardiac output after ibopamine were from 63 +/- 35 to 72 +/- 40 ml (p less than 0.05) and 4.6 +/- 1.7 to 5.4 +/- 2.1 L/min (p = 0.05), respectively. The contribution of atrial systole to total diastolic filling increased from 32 +/- 10% at baseline to 37 +/- 12% (p less than 0.05) after 30 minutes and persisted for at least 120 minutes. The distribution of diastolic filling was significantly altered after ingestion of ibopamine as reflected by a decrease in the ratio of the time-velocity integrals of left ventricular filling during early diastole and atrial systole (Ei/Ai) from 2.44 +/- 1.08 at baseline to 1.98 +/- 0.97 (p less than 0.05) 30 minutes after drug. The decrease in the Ei/Ai persisted for at least 120 minutes. The duration of the effect of ibopamine on diastolic filling persisted longer than its effect on augmenting systolic function. The positive effect of ibopamine on systolic function makes it a promising drug in the treatment of congestive heart failure.

Thallium-201 myocardial perfusion scintigraphy is reported to be a less accurate diagnostic test for coronary artery disease in women than in men. We retrospectively analyzed 34 Tl-201 studies obtained in 28 symptomatic women and compared them with those obtained in 32 men during the same interval. Three criteria were tested: criterion 1 was defined as abnormal scans showing any defect; criterion 2, scans showing only transient (reversible) defects; and criterion 3, scans showing either transient or "significant" (i.e., not due to breast attenuation) fixed defects. The sensitivity in women was 1.00, 0.73, and 0.93, respectively; the specificity, 0.26, 0.84, and 0.85. The best values in men were a sensitivity of 1.00 and a specificity of 0.86. The three criteria were then prospectively tested in 33 scans of 29 additional women. The sensitivity was 0.90, 0.65, and 0.80, respectively, and the specificity, 0.18, 1.00, and 0.92. Defects (usually fixed) due to breast attenuation artifact were seen frequently (30%). Criterion 3 best differentiates such defects from those resulting from coronary artery disease, making Tl-201 myocardial perfusion scintigraphy as accurate in women as in men.

The relationship of regional and global left ventricular function to aortic flow dynamics during exercise was determined in 14 normal subjects and 14 patients with coronary artery disease. Doppler and two-dimensional echocardiographic studies were performed before, during, and immediately after an exercise test by the Bruce protocol. Two-dimensional echocardiography was used to determine the ejection fraction and new wall motion abnormalities. The peak ejection velocity, stroke index, and cardiac index were calculated from the pulsed Doppler tracing. In normal subjects the ejection fraction increased significantly (p less than .001) from rest (0.51 +/- 0.07) to peak exercise (0.61 +/- 0.07), while the response in coronary patients was blunted (0.49 +/- 0.11 vs 0.48 +/- 0.16). Similarly, the change in peak ejection velocity throughout exercise in normal subjects (from 0.71 +/- 0.12 to 1.50 +/- 0.35 m/sec) was significantly (p less than .01) greater than that in patients with coronary artery disease (from 0.61 +/- 0.13 to 0.90 +/- 0.29 m/sec). There was a good correlation between the percent change in peak ejection velocity and the percent change in ejection fraction from rest to peak exercise in the entire study group (rs = .64) and in the patients with coronary artery disease (rs = .84). These preliminary data suggest that exercise-induced changes in Doppler echocardiographic variables may offer a potential adjunct in the evaluation of patients with ischemic heart disease.

A total of 102 patients aged 65 to 78 years underwent valvular replacement between 1975 and 1980. Calcific aortic stenosis was, by far, the commonest lesion (54 cases), followed by mitral stenosis (16 cases), mitral incompetence (14 cases), aortic incompetence (10 cases) and double valve lesions (8 cases). Sixty four patients underwent aortic valve replacement with 7 early deaths (10,9 p. 100). There were 30 mitral valve replacements with 7 deaths (23,3 p. 100) and 8 patients had double valve surgery with 4 deaths (50 p. 100). Aorto-coronary bypass grafting was associated in 25 cases with a 20 p. 100 mortality. Changes in the technique of peroperative myocardial protection have considerably reduced early mortality which has fallen from over 20 p. 100 to 2,9 p. 100 since the use of cardioplegia with local and systemic hypothermia. There was a higher surgical mortality in patients with poor left ventricular function, cardiomegaly and severe symptomatic incapacity. Non-fatal postoperative complications were common (50 p. 100 of survivors). There were 12 late deaths, 75 p. 100 of which were related to cardiovascular causes. The actuarial survival rate was 65,5 +/- 6 p. 100, 5 years after surgery. When operative mortality was excluded, the 5 year survival rate of the operated patients did not differ from that of the general populations of the same age (79,8 p. 100). Only 5 of our patients were lost to follow-up. Of the survivors, 95,5 p. 100 were asymptomatic or improved by at least one functional grade after an average postoperative period of 30 months. The incidence of late haemorrhagic complications in patients on anticoagulants was 11 p. 100.(ABSTRACT TRUNCATED AT 250 WORDS)

The prognostic value of early exercise testing after successful coronary angioplasty was determined in 196 and 225 consecutive patients with single-vessel and multivessel coronary disease, respectively, who underwent a symptom-limited exercise test within 30 days of the procedure. The incidence of exercise-induced ST segment depression greater than or equal to 1 mm was significantly greater in patients with multivessel versus single-vessel disease (27% versus 14%; p less than 0.005) and in patients with multivessel coronary disease who had incomplete versus complete revascularization (36% versus 10%; p less than 0.001). An abnormal exercise ECG result was associated with a significantly increased risk of cardiac events in patients with multivessel disease but not in patients with single-vessel disease. Exercise-induced angina occurred in a small and similar proportion of patients with single and multivessel coronary disease (8% versus 12%). The presence of exercise-induced angina was associated with a higher incidence of follow-up cardiac events in patients with multivessel disease and incomplete revascularization (52% versus 33%; p less than 0.05). Exercise duration was significantly less in patients with multivessel disease who had a subsequent cardiac event compared with that in patients who did not have such an event (458 +/- 168 versus 519 +/- 156 seconds; p = 0.01). Thus an abnormal exercise ECG finding within 1 month of successful coronary angioplasty is predictive of subsequent cardiac events in patients who have multivessel disease. The prognostic content of the test might be further improved if the test were performed several months after the procedure when the risk of restenosis is greatest.

To determine whether coronary artery bypass surgery would prolong survival in patients with silent myocardial ischemia during exercise testing, the data on 692 such patients from the Coronary Artery Surgery Study (CASS) registry were analyzed. The patients were followed up for up to 7 years after medical (n = 424) or surgical (n = 268) therapy. Stratification of patients into subsets was based on the results of cardiac catheterization. Surgical benefit was greatest in the patients with three vessel coronary artery disease or abnormal left ventricular function. Among the 75 patients with three vessel coronary disease and left ventricular dysfunction, the 7 year survival rate was 37% for the medical group and 90% for the surgical group (p less than 0.0001). Thus, among patients with silent myocardial ischemia during exercise testing in this nonrandomized study, survival appeared to be enhanced by coronary artery bypass surgery in subsets of patients with severe coronary artery disease and abnormal left ventricular function.

Determination of the restenosis rate after multilesion percutaneous transluminal coronary angioplasty is an important consideration in defining expanded indications for the procedure. Of 209 patients who underwent successful multilesion coronary angioplasty, 55 symptomatic and 74 asymptomatic patients were restudied an average of 7 +/- 4 months after dilation. The restenosis rate was 82% (45 of 55) in the symptomatic patients and 30% (22 of 74) in the asymptomatic patients (p less than 0.001). Only 4% of the asymptomatic patients had restenosis at more than one dilation site. When only patients who developed a restenosis were considered, the restenosis occurred at more than one dilation site in 47% (21 of 45) of the symptomatic group versus 14% (3 of 22) of the asymptomatic group (p less than 0.05). When all recurrent stenoses were examined, the severity of the luminal narrowing was greater than or equal to 70% in 64% (45 of 70) of the stenotic lesions in the symptomatic patients versus 31% (8 of 26) of the stenotic lesions in the asymptomatic patients (p less than 0.05). Proximal left anterior descending coronary artery disease, increased length of the stenotic narrowing, male gender and diabetes were associated with an increased incidence of restenosis by multivariate analysis. Patient-related variables were not predictive of multilesion restenosis. In conclusion, the majority of patients are clinically improved after multilesion coronary angioplasty. Recurrent symptoms after multilesion coronary angioplasty are frequently associated with multilesion restenosis and a more severe degree of restenotic narrowing. Restenosis at more than one dilation site is uncommon in the asymptomatic patient.(ABSTRACT TRUNCATED AT 250 WORDS)

Exercise electrocardiographic stress testing was performed in 81% of the 780 patients randomized in the Coronary Artery Surgery Study at entry. The cumulative survival at the end of 7 year follow-up was 90% for those assigned to surgical treatment and 88% for those assigned to medical therapy (p = NS). These survival rates did not differ significantly from either those of the entire randomized cohort or those of the 149 patients who did not have a qualifying exercise test at baseline. No differences in important baseline characteristics existed between those who were exercised and not exercised at entry. Stratification of patients according to the degree of ST segment depression (less than 1 mm, greater than or equal to 1 mm, greater than 2 mm) and final exercise stage achieved during a Bruce protocol treadmill test (final stage less than or equal to 1, stage 2 and greater than or equal to stage 3) failed to show any significant differences in 7 year survival rates between medically and surgically assigned patients. Additionally no differences in survival were noted within either the medical or surgical groups regardless of the degree of ST segment depression or the final stage achieved. The presence of exercise-induced angina, however, identified patients who had a survival advantage if assigned to surgical therapy, with a 7 year survival rate of 94% compared with 87% for medically assigned patients (p = .007).(ABSTRACT TRUNCATED AT 250 WORDS)

Introduction of a reliable method for continuous monitoring of mixed venous oxygen saturation has focused attention on the therapeutic and prognostic implications of this value. It is generally agreed that mixed venous oxygen saturation in the 40 to 60 percent range is associated with substantial patient morbidity and mortality if not rapidly corrected. However, several patients with chronic low cardiac output syndrome who have had mixed venous oxygen saturation of less than 40 percent for prolonged periods of time and who have not had decompensation were observed. Three representative patients with these findings are described and mechanisms put forth that may account for the observed relations between mixed venous oxygen saturation and mortality in these and other patients.