Is peripheral arterial pressure a satisfactory substitute for ascending aortic pressure when measuring aortic valve gradients?

Substitution of peripheral arterial pressure for ascending aortic pressure is a common but poorly validated practice in the assessment of aortic valve gradients by catheterization. The accuracy of this practice was assessed by comparing the left ventricular-ascending aortic mean gradient in 26 cases of aortic stenosis with the left ventricular-femoral artery gradient, both with and without compensation for temporal delay in femoral artery pressure. Aligned left ventricular-femoral artery gradients (matching upstrokes to compensate for peripheral time delay) underestimated the left ventricular-ascending aortic gradient by 10 mm Hg (range 0 to -17). Unaltered simultaneous left ventricular-femoral artery gradients overestimated the left ventricular-ascending aortic gradient by an average of 9 mm Hg (range +1 to +18). For both peripheral techniques, the error was relatively constant throughout the range of aortic valve gradients. The most accurate estimate of both aortic valve gradient and area was obtained by averaging the gradients and areas derived from aligned and unaltered left ventricular-peripheral arterial simultaneous tracings. Although only occasionally critical for clinical decision-making, these errors may be overwhelming in certain types of research applications, such as comparisons of valve prosthesis gradients and serial evaluations of aortic stenosis. An additional source of error is a coexistent peripheral arterial gradient that was present in 21% of otherwise technically suitable patients in the screened study group.

Postmyocardial infarction pain and infarct extension in the coronary care unit: role of two-dimensional echocardiography.

Recent data suggest that patients who manifest extension of their acute myocardial infarct have a worse prognosis than to those who do not have this complication and, if identified early, may be candidates for more aggressive intervention. Serial two-dimensional echocardiography was used to diagnose myocardial infarct extension in 33 consecutive patients and its sensitivity was compared with that of electrocardiography (ECG) and serum creatine kinase determination. Infarct extension was diagnosed clinically using ECG and enzymatic criteria. The echocardiograms were scored using a weighted regional scoring system, with each segment of the left ventricle ascribed a percent of the total left ventricular mass. Abnormal regions were summed to yield a percent asynergy. In the postinfarction period, 19 episodes of acute ischemia occurred; in 9 of these episodes clinical extension was confirmed, and in 7 of the 9 episodes echocardiographic extension was detected. In the patients in whom infarct extension was documented clinically, the mean asynergy score increased from a mean of 19.2 +/- 11.3% to 36.1 +/- 18.2% (p less than 0.01). Where no extension was detected, the asynergy score improved from the initial 31.5 +/- 24.1% to 28.3 +/- 21.9% (p less than 0.05). The extent of the change in echocardiographic wall motion abnormality was not predicted by the amount of creatine kinase reelevation. Electrocardiography alone failed to distinguish which episodes of ischemia represented infarct extension and which did not. Greater degrees of asynergy were associated with worse in-hospital mortality. Two-dimensional echocardiography is a useful method for detecting myocardial infarct extension providing a means of assessing functional impact and prognosis.

Acute reduction in functional infarct expansion with late coronary reperfusion: assessment with quantitative two-dimensional echocardiography.

Reperfusion performed too late to salvage myocardium decreases chronic infarct expansion in experimental animals. However, the acute effects of delayed reperfusion are not known. Twenty-two dogs underwent 3 (n = 8), 4 (n = 8) or 6 h (n = 6) of circumflex artery occlusion followed by 3 h of reperfusion. Effects of reperfusion on diastolic expansion were assessed in two ways: 1) change in mean radius of curvature of the infarct segment, and 2) change in the ratio of the length of the diameter from the center of the infarct zone to the opposite wall (septal-lateral diameter) to the length of the diameter perpendicular to this (anteroposterior diameter). Effects on systolic expansion were examined with quantitative two-dimensional echocardiographic systolic thickening analysis. Delayed reperfusion produced an immediate decrease in diastolic infarct expansion. The ratio of septal-lateral/anteroposterior diameters, which had increased with occlusion from a preocclusion baseline of 0.98 +/- 0.06 to 1.13 +/- 0.08 (p less than 0.001), decreased with reperfusion to 1.02 +/- 0.07 at 15 min and 1.03 +/- 0.08 at 3 h of reperfusion (p = 0.001). This was due solely to a decrease in the septal-lateral diameter. The radius of curvature of the infarcted segment increased from 2.1 +/- 0.5 cm before reperfusion to 2.74 +/- 0.8 cm at 15 min and 2.6 +/- 0.85 cm at 3 h of reperfusion (p = 0.009). This occurred despite a significant (13.6%) decline in end-diastolic cavity area and is compatible with flattening of the reperfused infarct region. Systolic infarct expansion also improved slightly.(ABSTRACT TRUNCATED AT 250 WORDS)

In vivo prediction of the transmural extent of experimental acute myocardial infarction using contrast echocardiography.

Acute myocardial infarction progresses radially from endocardium to epicardium within the ischemic area. The amount of progression is highly variable, but depends largely on the transmural distribution of myocardial blood flow. Recent contrast echocardiographic observations indicate that slowly appearing low levels of contrast enhancement are often seen in the ischemic region, particularly in the epicardial level, and that ischemic regions which show these low levels of contrast have significantly more blood flow than those that do not. This study was designed to determine whether the transmural distribution of this delayed contrast enhancement can sufficiently discriminate between regions of high and low flow to serve as an in vivo predictor of the transmural extent of acute infarction. Twenty-four dogs had acute circumflex coronary ligation which was maintained for 6 hours. Contrast echocardiographic studies were performed at the level of the mitral chordae 2 hours after occlusion using a dilute hydrogen peroxide and blood solution as a contrast agent. Comparison was made with the pathologic infarct measured by triphenyltetrazolium chloride staining. The mean transmural extent of infarction ranged from 0 to 89% and was predicted in vivo by the transmural extent of the delayed contrast defect (r = 0.92; infarction [percent transmural] = 0.74 contrast [percent transmural] + 11%; SEE = 10%). Reproducibility for the transmural extent of delayed contrast defects was good (r = 0.89 to 0.98.) These data further support the concept that the transmural distribution of delayed contrast enhancement parallels blood flow and indicate that the mean transmural extent of acute infarction can be predicted in vivo 2 hours after coronary occlusion from the residual contrast defect.

Percutaneous transluminal coronary angioplasty versus medical therapy for stable angina pectoris: outcomes for patients with double-vessel versus single-vessel coronary artery disease in a Veterans Affairs Cooperative randomized trial. Veterans Affairs ACME InvestigatorS.

OBJECTIVES: This study sought to assess outcomes of men with double-vessel coronary artery disease randomly assigned to treatment by percutaneous transluminal coronary angioplasty (PTCA) or medical therapy, compared with previously reported outcomes for men with single-vessel disease. BACKGROUND: We previously reported that PTCA provides better symptom relief and treadmill performance than medical therapy for men with stable angina pectoris due to single-vessel disease. Whether this advantage applies to patients with double-vessel disease is unknown. METHODS: Male patients (n = 328) with stable angina pectoris and ischemia on treadmill testing were randomly assigned to PTCA or medical therapy; 101 patients had double-vessel disease, and 227 had single-vessel disease. Symptoms, treadmill performance, quality of life score, coronary stenosis and myocardial perfusion were compared at baseline and at 6 months. Patients were followed up for up to 6 years and underwent additional treadmill testing 2 to 3 years after randomization. RESULTS: PTCA-treated and medically treated patients with double-vessel disease experienced comparable improvement in exercise duration (+1.2 vs. +1.3 min, respectively, p = 0.89), freedom from angina (53% and 36%, respectively, p = 0.09) and improvement of overall quality of life score (+1.3 vs. +4.4, respectively, p = 0.32) at 6 months compared with baseline. This contrasts with greater advantages favoring PTCA by these criteria in patients with single-vessel disease (p = 0.0001 to 0.02). Trends present at 6 months persisted at late follow-up. Patients undergoing double-vessel dilation had less complete initial revascularization (45% vs. 83%) and greater average stenosis of worst lesions at 6 months (74% vs. 56%). Likewise, patients with double-vessel disease showed less improved myocardial perfusion imaging (59% vs. 75%). CONCLUSIONS: PTCA is beneficial in male patients with double-vessel disease; however, we cannot demonstrate the same advantage over medical therapy seen in similar patients with single-vessel disease. Less complete revascularization and greater restenosis for patients having multiple dilations would account for these findings. Alternatively, a type 2 error might be operative. Technical advances since completion of this trial might improve these outcomes. These findings warrant further investigation in a larger trial.

Evaluation of exercise thallium scintigraphy versus exercise electrocardiography in predicting survival outcomes and morbid cardiac events in patients with single- and double-vessel disease. Findings from the Angioplasty Compared to Medicine (ACME) Study.

OBJECTIVES: We sought to evaluate the prognostic ability of cardiac exercise stress tests in predicting cardiac mortality and morbidity in a low risk group of patients with established coronary artery disease (CAD). BACKGROUND: Although previous studies have demonstrated the superior value of stress nuclear cardiac scintigraphy in the prognosis of patients with CAD, none of these studies have focused on patients with a proven angiographic low risk profile (i.e., single- and double-vessel CAD). METHODS: Three hundred twenty-eight patients with documented single- and double-vessel disease were treated by random assignment to percutaneous transluminal coronary angioplasty or medical therapy in the Angioplasty Compared to Medicine (ACME) trial. Six months after randomization, maximal symptom-limited exercise tests were performed with electrocardiography (n = 300) and thallium scintigraphy (n = 270). Patients were followed up for a minimum of 5 years thereafter. RESULTS: A reversible thallium perfusion deficit documented after 6 months of either therapy was associated with an adverse mortality outcome (18% mortality rate with a reversible thallium perfusion defect and 8% mortality rate with no reversible thallium perfusion deficit, p = 0.02). Moreover, an important mortality gradient was demonstrated in relation to the number of reperfusing defects (0 = 7%, 1 to 2 = 15%, >3 = 20%, p = 0.04). Exercise electrocardiography did not predict this mortality outcome. CONCLUSIONS: A reversible thallium perfusion deficit demonstrated 6 months after medical therapy or coronary angioplasty is a valuable prognostic marker in patients with angiographically documented single- and double-vessel disease and is superior to exercise electrocardiography in this regard.

Intraaortic balloon counterpulsation as a temporary support measure in decompensated critical aortic stenosis.

Intraaortic balloon counterpulsation was instituted in two adult patients whose condition was rapidly deteriorating because of critical decompensated valvular aortic stenosis. The acute hemodynamic effect of counterpulsation in these patients was compared with the effect of counterpulsation in three control patients with unstable angina and no aortic valve disease. Augmentation of aortic diastolic pressure was similar in both groups; however, in contrast to the patients with unstable angina, the patients with aortic stenosis had no decrease in left ventricular systolic pressure. Counterpulsation resulted in an increase in the transvalvular pressure gradient, which was associated with a slight increase in stroke volume. In both patients with aortic stenosis, the institution of counterpulsation resulted in marked clinical improvement, which facilitated successful valve replacement surgery. The benefit from counterpulsation in critically decompensated aortic stenosis appears to be derived almost entirely from augmentation of the diastolic coronary filling gradient. The improvement that results from counterpulsation suggests that ischemia is the major cause of decompensation.

Propranolol as primary therapy for thyrotoxicosis.

It has been suggested that propranolol hydrochloride alone is effective in the treatment of thyrotoxicosis. To test this hypothesis, eight mildly thyrotoxic individuals were prospectively studied for an average of eight months, during which propranolol alone was administered and thyroid function tests, cardiac systolic time intervals, and body densities were sequentially measured. Two patients became euthyroid. The others had adequate but incomplete symptomatic control. Weight loss was not corrected, but no changes in lean body mass were induced. The augmented myocardial contractility of thyrotoxicosis, as determined by systolic time intervals, improved but failed to return completely to normal. Thus, systolic time intervals are a practical means of following the peripheral response to chronic beta-adrenergic blockage in thyrotoxic patients. However, these observations do not support the use of propranolol alone as the first choice of therapy for thyrotoxicosis.

Clinical use of thrombolytic agents in venous thromboembolism.

The use of thrombolytic agents in venous thromboembolism has been shown to be highly effective. Patients treated with lytic agents show more rapid clot resolution and lung reperfusion and more rapid and greater reversal of the abnormal hemodynamic responses to pulmonary embolism than patients receiving heparin. Moreover, lytic therapy removes thromboemboli more completely from the pulmonary microcirculation, whereas residual thromboemboli tend to accumulate with heparin therapy. In addition, lytic therapy tends to preserve the venous valves, whereas distortion and destruction occur with heparin therapy. Hence, lytic therapy confers a number of short- and long-term benefits not observed with heparin therapy.

Assessment of severity of mitral stenosis by echocardiographic leaflet separation.

Mitral valve area (MVA) determined at cardiac catheterization was compared with M mode echocardiographic measurements in 44 patients with mitral stenosis and no substantial mitral regurgitation. Despite statistically significant correlations, measurements of anterior leaflet motion, including rate of diastolic closure (EF slope) were not useful in predicting severity of stenosis. In contrast, maximal diastolic separation of anterior and posterior leaflets (SEP) was more closely correlated with MVA and appears to have some predictive value. Narrow separation was associated with severe mitral stenosis. Wide separation was associated with relatively mild stenosis. Intermediate values in 16 of 44 patients (36%) were not of predictive value. Recognizing this limitation, measurement of maximal diastolic mitral leaflet separation from M mode echocardiograms is proposed as a simple and useful method for assessing severity of mitral stenosis.

The efficacy of exercise as an aid for smoking cessation in women: a randomized controlled trial.

BACKGROUND: Smoking prevalence rates among women are declining at a slower rate than among men. OBJECTIVE: To determine if exercise, a healthful alternative to smoking, enhances the achievement and maintenance of smoking cessation. METHODS: Two hundred eighty-one healthy, sedentary female smokers were randomly assigned to either a cognitive-behavioral smoking cessation program with vigorous exercise (exercise) or to the same program with equal staff contact time (control). Subjects participated in a 12-session, group-based smoking cessation program. Additionally, exercise subjects were required to attend 3 supervised exercise sessions per week and control subjects were required to participate in 3 supervised health education lectures per week. Abstinence from smoking was based on self-report, was verified by saliva cotinine level, and was measured at 1 week after quit day (week 5), end of treatment (week 12), and 3 and 12 months later (20 and 60 weeks after quit day, respectively). RESULTS: Compared with control subjects (n = 147), exercise subjects (n = 134) achieved significantly higher levels of continuous abstinence at the end of treatment (19.4% vs 10.2%, P = .03) and 3 months (16.4% vs 8.2%, P=.03) and 12 months (11.9% vs 5.4%, P=.05) following treatment. Exercise subjects had significantly increased functional capacity (estimated VO2 peak, 25+/-6 to 28+/-6, P<.01) and had gained less weight by the end of treatment (3.05 vs 5.40 kg, P = .03). CONCLUSIONS: Vigorous exercise facilitates short- and longer-term smoking cessation in women when combined with a cognitive-behavioral smoking cessation program. Vigorous exercise improves exercise capacity and delays weight gain following smoking cessation.

Resting early peak diastolic filling rate: a sensitive index of myocardial dysfunction in patients with coronary artery disease.

Resting first-pass radionuclide angiocardiography (RNA) was used to derive left-ventricular (LV) peak diastolic filling rates (PFR) in normals (Group 1:N = 12) and in patients with coronary artery disease (CAD), both without (Group 2:N = 27) and with previous myocardial infarction (Group 3:N = 23). Resting peak filling rates were significantly depressed in both Group 2 (1.61 +/- 0.36; p less than 0.01) and Group 3 (1:35 +/- 0.26; p less than 0.001) patients when compared with Group 1, normals (2.14 +/- 0.63). Even though LV systolic function of Group 2 patients was normal and comparable to that in Group 1 (EF = 0.55 +/- 0.06 against EF 0.55 +/- 0.06 NS), diastolic dysfunction [PFR less than 1.61 end diastolic volume/sec (EDV/sec)] was present at rest in 14 of 27 (52%). Depressed PFR values was also seen in 20 of 23 Group 3 patients (87%). It appears that (a) resting PFR is a sensitive and easily obtainable parameter of the diastolic dysfunction associated with CAD; (b) abnormal PFR values are seen in almost all patients with previous myocardial damage, and (c) a significant proportion of CAD patients without any evidence of abnormal systolic function have depressed resting PFR of the LV.

Diagnosis of acute myocardial infarction in patients undergoing open heart surgery: a comparison of serial myocardial imaging with cardiac enzymes, electrocardiography, and vectorcardiography.

In 44 consecutive patients undergoing elective open heart surgery (OHS), serial electrocardiograms (ECG), vectorcardiograms (VCG), serum CPK, cardiac isoenzymes (CPKMB), and myocardial images using Tc-99m pyrophosphate were obtained, before and after the operation, for the detection of acute myocardial infarction (AMI). Twenty-nine patients developed one or more positive tests postoperatively. Two patients had positive myocardial scintiscans; both had other evidence of infarction. Conversely, the appearance of CPKMB, or new ECG and VCG changes, occurred frequently without evidence of infarction, and were not associated with the development of a positive scintiscan. The results show that false-negative results are infrequent in patients imaged early after OHS, and that cardiac surgical procedures do not cause a high incidence of false-positive scintigrams. Consequently, radionuclide imaging for AMI offers an important adjunct for excluding acute infarction following open heart surgery.

Randomized, placebo-controlled evaluation of lidoflazine in patients receiving beta-blocker therapy with propranolol: improvement in anginal symptoms and exercise tolerance with combined drug therapy.

Twenty-nine patients symptomatic despite beta-blocker therapy were entered into a randomized, double-blind, placebo-controlled, crossover trial of lidoflazine added to propranolol. After clinically documented beta blockade was achieved, patients were randomized to either propranolol plus placebo (P) or propranolol plus lidoflazine (L). Patients initially receiving lidoflazine (group with treatment sequence LP) showed improvement in exercise tolerance from propranolol alone (7.2 to 9.3 minutes, p less than 0.05). Those randomized initially to propranolol plus placebo (group with treatment sequence PL) had unchanged exercise tolerance (7.3 minutes). After 4 months, patients were crossed over to the alternative form of therapy. Patients (group PL) now receiving lidoflazine in addition to propranolol increased their exercise duration (7.8 minutes), but not, significantly. However, patients switched to propranolol plus placebo (group LP) continued to sustain their improved exercise capacity, showing a "carryover" effect. Symptomatic improvement was manifested by a statistically significant reduction in both anginal attack rate and nitroglycerin consumption. The therapeutic efficacy of combined therapy was associated with further blunting of the heart rate response to exercise achieved by beta blockade alone. The combination of agents was well tolerated.

Coronary calcification in the diagnosis of coronary artery disease.

Clinical, postmortem and angiographic studies of coronary calcification are reviewed to define the value of fluoroscopy in the diagnosis and management of coronary artery disease. Autopsy studies consistently show a unique association between calcification of the coronary arteries and atherosclerosis. The relation of coronary calcification to the presence of major stenosis is more variable but is strong enough to be of clinical value, particularly in the younger subject. The diagnostic value of fluoroscopy can be improved by attention to the detailed features of calcification observed with the technique. Combined use of fluoroscopy and exercise testing appears to be a valid and as yet unexploited approach to the noninvasive diagnosis of coronary stenosis. Fluoroscopy has been a neglected method of noninvasive diagnosis and is sufficiently promising to warrant greater clinical use.

Effects of left ventricular systolic function on left ventricular diastolic filling patterns in severe mitral regurgitation.

Significant mitral regurgitation (MR) may alter the normal pattern of Doppler detected left ventricular (LV) filling by causing a prominent early filling (E) wave velocity. The manner and extent to which the typical filling pattern of uncomplicated MR is affected by concomitant impaired LV systolic function has not been characterized. Twenty patients with severe LV systolic dysfunction (2-dimensional echocardiographic estimation of ejection fraction < or = 30%) and 21 age- and sex-matched case controls with normal systolic function (ejection fraction > or = 55%) were selected. In addition, 20 subjects with normal LV systolic function and no MR were analyzed as a reference group. Maximal E-wave velocity was increased and highest among MR patients with preserved LV systolic function (124 +/- 37 cm/s) than among those with LV systolic dysfunction (101 +/- 25 cm/s; p <0.05) and normal controls (74 +/- 18 cm/s; p <0.001). Concurrently, A-wave velocity was lowest in patients with systolic dysfunction and MR (47 +/- 23 cm/s; p <0.001) than in patients with normal systolic function and MR (79 +/- 33 cm/s) and normal controls (74 +/- 20 cm/s). Deceleration time of the E wave was longest among those with normal systolic function and MR (203 +/- 41 ms) than among those with systolic dysfunction and MR (152 +/- 35 ms; p <0.001) and normal controls (167 +/- 53 ms; p <0.05). Thus, systolic LV dysfunction in patients with severe MR, compared to patients with MR and normal LV systolic function, is associated with important changes in diastolic inflow velocities, including reduction of the maximal A-wave velocity to a greater extent than the E wave, resulting in an increased E/A ratio and shortening of deceleration time of the E wave.

Clinical appraisal of current nuclear and other noninvasive cardiac diagnostic techniques.

At a time of rapid increases in the cost of medical care and the application of complex invasive procedures to cardiovascular diagnosis, the use of noninvasive methods has aroused interest. This report discusses the usefulness and limitations of various noninvasive diagnostic methods including nuclear medicine techniques, echocardiography, exercise electrocardiography and determination of systolic time intervals. Emphasis is placed on the applicability of these methods to specific disease processes (such as ischemic heart disease, cardiac valve disease, pulmonary embolic disease), their relative merits, future potential and present shortcomings.

Programmed electrical stimulation of the heart in coronary artery disease.

The induction of ventricular arrhythmia in patients with a history of malignant ventricular arrhythmia by programmed electrical stimulation (PES) is associated with a poor prognosis. However, the incidence and significance of inducible arrhythmia in patients with stable coronary artery disease (CAD) who do not have a history of serious arrhythmia are unknown. We studied 32 such patients (31 men, mean age 55 years) with PES at the time of cardiac catheterization. Fourteen patients (Group I) manifested greater than or equal to 3 extraventricular responses when challenged with 1 to 3 propagated right ventricular extrastimuli during ventricular pacing. Twelve (86%) of these 14 had evidence of left ventricular dysfunction (LVD), defined by a global ejection fraction of less than 50% or regional wall motion abnormalities. The remaining 18 patients (Group II) manifested less than or equal to 2 responses to extrastimulation. Only 4 (22%) of these 18 had LVD. Proximal 3-vessel CAD was more frequent in Group I patients (10 of 14, 71%) than in Group II (7 of 18, 39%). Only 5 patients (4 from Group I and 1 from Group II) demonstrated complex arrhythmia during exercise testing or ambulatory monitoring. The induction of extraventricular responses during PES may serve as an independent marker of electrical instability in the coronary population and is a much more common finding in those with LVD.

Safety and efficacy of diltiazem hydrochloride for the treatment of stable angina pectoris: report of a cooperative clinical trial.

Sixty-three patients completed a multicenter 10 week, double-blind, parallel group protocol evaluating the efficacy of diltiazem versus placebo with respect to rate of attacks of angina, nitroglycerin consumption and duration of treadmill exercise. An additional 36 patients were evaluated for drug safety. A 4 week placebo lead-in phase was followed by a 2 week dose titration period and two treatment evaluation periods of 2 weeks each. Both diltiazem and placebo were associated with a significant reduction in weekly frequency of angina from the baseline rate. Intergroup comparison disclosed a significantly greater reduction for the patients receiving diltiazem than for those receiving placebo. A similar reduction was noted for nitroglycerin consumption. Total exercise duration at week 10 was statistically greater in patients treated with diltiazem. Diltiazem was well tolerated. No abnormalities in hematologic profiles or in routine serum chemistry values were observed; electrocardiographic P-R and QRS intervals were unaffected. Adverse effects that could have been related to drug administration were reported in 11 patients who received diltiazem and in 12 patients who received placebo. Of the 17 episodes in the diltiazem group only 3 were considered significant and drug-related, and only one of these resulted in discontinuation of the drug.

Effects of left ventricular shape and captopril therapy on exercise capacity after anterior wall acute myocardial infarction.

The importance of left ventricular (LV) shape in determining exercise capacity was assessed in 40 male patients with LV dysfunction after anterior acute myocardial infarction (AMI). Because captopril therapy is known to improve exercise capacity in this patient population, the potential interaction between LV shape and captopril therapy was also evaluated. Patients underwent cardiac catheterization 2 to 4 weeks after AMI followed by randomization to receive placebo or captopril. LV shape was defined from biplane ventriculography by a sphericity index (volume observed/volume of sphere using long axis as diameter). Quarterly clinical assessments and maximal exercise testing were performed. A cumulative heart failure score, specific activity scale and average exercise time for the year were calculated. A greater shape distortion (increasing sphericity index) was associated with increased LV volumes, decreased ejection fraction and a larger abnormally contracting segment. Sphericity index was the only independent predictor of average exercise duration in the placebo group. Placebo-treated patients in the tercile with the most spherical ventricles had not only the lowest exercise capacity (p less than 0.01), but also accumulated the highest heart failure (p less than 0.05) and specific activity scale (p less than 0.05) scores. Captopril-treated patients with the same baseline distortion of LV shape did not manifest these shape-dependent objective and subjective measures of reduced functional capacity.