Showing papers on "Ejection fraction published in 1982"

Survival of medically treated patients in the coronary artery surgery study (CASS) registry.

Abstract: The objective of this study was to evaluate the impact on survival of the anatomic extent of obstructive coronary artery disease and of two measures of left ventricular (LV) performance. This study is based on 20,088 patients without previous coronary artery bypass graft surgery who were enrolled in the registry of the National Heart, Lung, and Blood Institute Coronary Artery Surgery Study from 1975 to 1979. The cumulative 4-year survival of medically managed patients was analyzed to determine the survival of specific subsets of patients with obstructive coronary disease. The vital status of 99.8% of the patients was known. The 4-year survival of medically treated patients with no significant obstructive disease was 97%, in contrast to 92%, 84% and 68% in patients with one-, two- and three-vessel disease, respectively. The presence of left main coronary artery disease decreased survival significantly. The 4-year survival decreased from 70% to 60% in patients with three-vessel disease when significant obstruction of the left main coronary artery was also present. Patients with significant coronary artery disease who had an ejection fraction of 50--100%, 35--49%, and 0--34% had a 4-year survival of 92%, 83% and 58%, respectively. The systolic contraction pattern was assessed in five selected segments and given a score of 1--6, with a score of 1 for normal function, increasing to 6 if an aneurysm was present. In a patient with normal LV contraction in all five segments of the LV ventricular angiogram, the LV score would equal 5. Patients with an LV score of 5--11, 12--16 and 17--30 had 4-year survivals of 90%, 71% and 53%, respectively. Patients with good LV function (a score of 5--11) had a 4-year survival of 94%, 91% and 79% for one-, two- and three-vessel disease, respectively. Patients with poor left ventricular function (score of 17--30) had a 4-year survival rate of 67%, 61% and 42% in one-, two- and three-vessel disease, respectively. Thus, LV function is a more important predictor of survival than the number of diseased vessels.

Determinants of prognosis in survivors of myocardial infarction: a prospective clinical angiographic study.

Abstract: To identify predictors of late mortality, 259 consecutive men (less than or equal to 60 years old) who survived acute myocardial infarctions were catheterized one month after admission and were then followed for a mean of 34 months. Nineteen patients (7 per cent) died during the observation period. Of 79 base-line descriptors, 17 proved to be univariate predictors of survival. Cox regression analysis demonstrated that the ejection fraction (P less than 0.001), the number of diseased vessels (P less than 0.005), and the occurrence of congestive heart failure in the coronary unit (P less than 0.01) were the only independent predictors of survival. Risk stratification showed that the probability of survival at four years was highest in patients with normal ejection fractions (96 to 100 per cent, depending on the number of diseased vessels) and lowest in those with ejection fractions below 20 per cent (3o to 75 per cent). The prognosis in patients with ejection fractions between 21 and 49 per cent was significantly worse (78 per cent) than in those with normal ejection fractions only in the group with three-vessel involvement (P less than 0.01). Since most survivors of myocardial infarction who are likely to have their lives prolonged by coronary-artery bypass surgery are in this group, it is reasonable to limit routine coronary angiography to the 56 per cent of survivors who have ejection fractions between 21 and 49 per cent.

Prognostic value of exercise testing, coronary angiography and left ventriculography 6--8 weeks after myocardial infarction.

Abstract: This study provides data on a consecutive series of 179 survivors of acute myocardial infarction (MI) who had symptom-limited treadmill exercise testing, coronary angiography and left ventriculography within 6--8 weeks after infarction. No patient died. The prevalence of multivessel disease was higher in the symptomatic survivors (79%) (p less than 0.001). The prevalence of multivessel disease in inferior MI was 63% and in anterior MI 42% (p less than 0.001). Left ventricular impairment was more severe in anterior and preexisting MI than in inferior and nontransmural MI (p less than 0.005). During a mean follow-up of 28 months, 11 cardiac deaths and 12 reinfarctions occurred. The total mortality rate was 22% (10 of 46) in patients with an ejection fraction less than 30% or three-vessel disease and 1% (one of 133) in patients with an ejection fraction greater than or equal to 30% and one- or two-vessel disease (p less than 0.001). A group at high risk of mortality is thus identified by angiography. The total reinfarction rate was 9% (11 of 121) in patients with an exercise tolerance of less than 10 minutes (Bruce protocol) and 2% (one of 58) in patients with an exercise tolerance of 10 minutes or more (p less than 0.1). The 58 patients who had an exercise tolerance of 10 minutes or more had a very low risk for cardiac death or reinfarction.

Abnormal left ventricular function in hyperthyroidism: evidence for a possible reversible cardiomyopathy.

Abstract: We assessed the effects of exercise and beta-adrenoceptor blockade on left ventricular ejection fraction (LVEF) measured by radionuclide ventriculography in nine patients with uncomplicated hyperthyroidism. Patients were studied in both the hyperthyroid and euthyroid states. The hyperthyroid state was characterized by a high LVEF at rest but--paradoxically--by a significant fall (P less than 0.01) in LVEF during exercise. At the same workload and at the same heart rate, patients had a restoration of the normal rise in LVEF during exercise when they were euthyroid. The LVEF was greater during exercise (P less than 0.02) when the patients were euthyroid than when they were hyperthyroid. Pretreatment with propranolol caused similar reductions in resting LVEF in the hyperthyroid and euthyroid states; the drug attenuated the rise in LVEF during exercise when the patients were euthyroid, but did not influence the exercise-induced reduction in LVEF in hyperthyroidism. The abnormal left ventricular function observed during exercise in hyperthyroidism suggests a reversible functional cardiomyopathy, independent of beta-adrenoceptor activation, that is presumably a direct effect of an excess in circulating thyroid hormones.

A QRS scoring system for assessing left ventricular function after myocardial infarction.

Abstract: A QRS scoring system for estimating the size of a myocardial infarct was evaluated in 55 patients who did not have left ventricular hypertrophy or conduction abnormalities. Serial 12-lead surface electrocardiograms were scored according to a 29-point system based on the duration of Q and R waves and on the ratios of R-to-Q amplitude and R-to-S amplitude. The scores were proportional to the severity of wall-motion abnormalities, which was determined by radionuclide blood-pool scanning and which correlated inversely with the radionuclide-determined left ventricular ejection fraction (LVEF). A score less than 3 was 93 per cent sensitive and 88 per cent specific for both severe regional dyssynergy and major depression of the global LVEF. The following equation was used to estimate the LVEF from the QRS score: LVEF (%) = 60 - (3 x QRS score). After acute myocardial infarction, an electrocardiogram can provide important indirect quantitative information about left ventricular function.

Exercise responses before and after physical conditioning in patients with severely depressed left ventricular function.

Abstract: The ability of patients with severely impaired left ventricular function to perform short-term exercise and to participate in a cardiac rehabilitation program and attain physical training effects was evaluated. Treadmill exercise tests were performed before and after physical conditioning in 10 patients with a prior myocardial infarction and a left ventricular ejection fraction at rest of less than 27 percent (range 13 to 26) determined by radionuclide angiography. All patients participated in a supervised exercise program with a follow-up period of 4 to 37 (mean 12.7) months. Baseline exercise capacity showed marked variability, ranging from 4.5 to 9.4 (mean 7.0 ± 1.9) METS, and improved to 5.5 to 14 (mean 8.5 ± 2.9) METS after conditioning (p = 0.05). The oxygen pulse (maximal oxygen uptake/maximal heart rate) before and after conditioning was used to assess a training effect and increased significantly from 12.8 ± 2.0 to 15.7 ± 3.2 ml/beat (p

Physiologic correlates of right ventricular ejection fraction in chronic obstructive pulmonary disease: A combined radionuclide and hemodynamic study☆

Abstract: The pathophysiologic correlates of right ventricular ejection fraction, as well as its relation to contractile function as assessed by systolic pressure-volume data, were evaluated in 20 patients with chronic obstructive pulmonary disease. Radionuclide and hemodynamic measurements were obtained simultaneously. Baseline determinations were obtained in all patients. In seven patients, studies were repeated after intravenous administration of sodium nitroprusside. This procedure allowed characterization of right ventricular performance at decreased afterload and provided two points necessary for definition of the right ventricular systolic pressure-volume relation. Seventeen of the 20 patients had a depressed right ventricular ejection fraction (less than 45 percent). There was a strong inverse linear correlation between right ventricular ejection fraction and afterload as assessed by peak or mean pulmonary arterial pressure (r = −0.81) and pulmonary vascular resistance index (r = −0.73). Right ventricular ejection fraction also correlated, although less strongly, with preload as assessed by right ventricular end-diastolic volume index (r = −0.56) and mean right atrial pressure (r = −0.51). It did not correlate with cardiac index, the ratio of peak pulmonary arterial pressure to right ventricular end-systolic volume index, arterial oxygen tension or left ventricular ejection fraction. After nitroprusside administration, mean arterial pressure, peak pulmonary arterial systolic pressure and pulmonary vascular resistance index decreased significantly. The slope (E) and the volume intercept (V 0 ) of each pressure-volume line were determined. Administration of dobutamine resulted in a leftward shift from the endsystolic pressure-volume line. There were poor correlations between E and right ventricular ejection fraction, as well as between E and the control ratio between pulmonary arterial systolic pressure and end-systolic volume index. These data demonstrate that, in addition to intrinsic contractile influences, right ventricular ejection fraction is highly dependent on afterload, but less dependent on preload. Right ventricular ejection fraction is a poor indicator of the slope of the systolic pressure-volume relation, raising questions concerning its use as an independent index of chamber contractility.

Cardiovascular effects of tricyclic antidepressants in depressed patients with chronic heart disease.

Abstract: Twenty-four depressed patients with heart disease were treated for four weeks in a double-blind trial of imipramine, doxepin, or placebo to assess the effects of tricyclic antidepressants on ventricular function and rhythm. The tricyclic antidepressants had no effect on left ventricular ejection fraction at rest or during maximal exercise, as measured by radionuclide ventriculograms obtained before and after treatment. Premature ventricular contractions were reduced by imipramine but were not consistently changed by doxepin or placebo. Treatment with imipramine and doxepin, but not placebo, was associated with significant improvement (P less than 0.001) in standard ratings of depression. Our findings underscore the need for a reappraisal of the cardiovascular risks of tricyclic antidepressants and suggest that in the absence of severe impairment of myocardial performance, depressed patients with preexisting heart disease can be effectively treated with these agents without an adverse effect on ventricular rhythm or hemodynamic function.

Improved left ventricular diastolic filling in patients with coronary artery disease after percutaneous transluminal coronary angioplasty.

Abstract: Left ventricular (LV) diastolic filling is abnormal at rest in many patients with coronary artery disease (CAD), even in the presence of normal resting LV systolic function. To determine the effects of improved myocardial perfusion on impaired. LV diastolic filling, we studied 25 patients with one-vessel CAD by high-temporal-resolution radionuclide angiography before and after percutaneous transluminal coronary angioplasty (PTCA). No patient had ECG evidence of previous myocardial infarction. Despite normal regional and global LV systolic function at rest in all patents, LV diastolic filling was abnormal (peak LV filling rate [PFR] less than 2.5 end-diastolic volumes (EDV)/sec or time to PFR greater than 180 msec) in 17 of 25 patients. Twenty-three patients had abnormal LV systolic function during exercise. After successful PTCA, LV ejection fraction and heart rate at rest were unchanged, but LV ejection fraction during exercise increased, from 52 +/- 8% (+/- SD) to 63 +/- 5% (p less than 0.001). LV diastolic filling at rest improved: PFR increased from 2.3 +/- 0.6 to 2.8 +/- 0.5 EDV/sec (p less than 0.001) and time to PFR decreased from 181 +/- 22 to 160 +/- 18 msec (p less than 0.001). Thus, a reduction in exercise-induced LV systolic dysfunction after PTCA, reflecting a reduction in reversible ischemia, was associated with improved LV diastolic filling at rest. These data suggest that in many CAD patients with normal resting LV systolic function and without previous infarction, abnormalities of resting LV diastolic filling are not fixed, but appear to be reversible manifestations of impaired coronary flow.

Precordial ST-segment depression during acute inferior myocardial infarction: clinical, scintigraphic and angiographic correlations

Abstract: The cause and associated pathophysiology of precordial ST-segment depression (ST decreases) during acute inferior myocardial infarction (IMI) are controversial. To investigate this problem, electrocardiographic findings in 48 consecutive patients with acute IMI were prospectively compared with results of coronary angiography, submaximal exercise thallium-201 (201TI) scintigraphy and multigated blood pool imaging, all obtained 2 weeks after IMI, and with clinical follow-up at 3 months. Patients were classified according to the admission ECG obtained 3.3 +/- 3.1 hours after the onset of chest pain. Twenty-one patients (group A) had no or less than 1.0 mm ST decreases, and 27 (group B) had greater than or equal to 1.0 mm ST decreases in two or more precordial (V1-6) leads. Patients in group B had more prolonged chest pain after admission to the coronary care unit than those in group A (2.8 +/- 3.0 vs 1.2 +/- 1.1 hours, p less than 0.03), greater summed ST-segment elevation in leads II, III, aVF (6.7 +/- 4.7 vs 3.3 +/- 4.5 mm, p less than 0.02), higher plasma peak creatine kinase levels (1133 +/- 781 vs 653 +/- 482 IU/l, p less than 0.01), a higher prevalence of "true posterior" infarction by ECG criteria (26% vs 5%, p less than 0.05), a lower radionuclide ejection fraction (46 +/- 9% vs 54 +/- 6%, p less than 0.001), more extensive infarct-related asynergy (p less than 0.001) and 201TI perfusion abnormalities (p less than 0.01), more complications during hospitalization (p less than 0.03), and more cardiac events at 3 months (p less than 0.02). There were no significant differences between group A and group B in the extent of underlying coronary disease, prevalence of left anterior descending coronary artery disease, exercise-induced ST decreases or angina, and 201TI defects or wall motion abnormalities in anterior or septal segments. Thus, patients with acute IMI who have associated precordial ST decreases have greater global and regional left ventricular dysfunction due to more extensive inferior or inferoposterior wall infarction, rather than concomitant anteroseptal ischemic injury.

Preoperative prediction of reversible myocardial asynergy by postexercise radionuclide ventriculography.

Abstract: Myocardial asynergy is sometimes reversed by coronary bypass, and a noninvasive method of predicting which assess are reversible would be desirable. To assess whether changes in myocardial wall motion observed immediately after exercise can differentiate reversible from nonreversible myocardial asynergy, we evaluated 53 patients by radionuclide ventriculography before and after exercise and again at rest after coronary bypass surgery. Preoperative improvement in wall motion immediately after exercise was highly predictive of the surgical outcome (average chance-corrected agreement, 91 per cent). At surgery the asynergic segments that had improved after exercise were free of grossly apparent epicardial scarring. The accuracy of these predictions for postoperative improvement was significantly greater (P less than 0.01) than that of analysis of Q waves on resting electrocardiography (average chance-corrected agreement, 40 per cent). In contrast, preoperative changes in left ventricular ejection fraction after exercise were not predictive of postoperative resting ejection fraction. We conclude that postexercise radionuclide ventriculography can be used to identify reversible resting myocardial asynergy. This test should prove effective in predicting which patients with myocardial asynergy are most likely to benefit from aortocoronary revascularization.

Prognostic implications of ventricular arrhythmias during 24 hour ambulatory monitoring in patients undergoing cardiac catheterization for coronary artery disease

Abstract: The prognostic importance of ventricular arrhythmias detected during 24 hour ambulatory monitoring was evaluated in 395 patients with and 260 patients without significant coronary artery disease. Ventricular arrhythmias were found to be strongly related to abnormal left ventricular function. A modification of the Lown grading system (ventricular arrhythmia score) was the most useful scheme for classifying ventricular arrhythmias according to prognostic importance. When only noninvasive characteristics were considered, the score contributed independent prognostic information, and the complexity of ventricular arrhythmias as measured by this score was inversely related to survival. However, when invasive measurements were included, the ventricular arrhythmia score did not contribute independent prognostic information. Furthermore, ejection fraction was more useful than the ventricular arrhythmia score in identifying patients at high risk of sudden death.

Intracoronary thrombolysis in acute myocardial infarction: Duration of ischemia as a major determinant of late results after recanalization

Abstract: To define the effect of duration of myocardial ischemia on the late results after successful thrombolysis in patients with acute transmural myocardial infarction, data on 39 patients treated with intracoronary infusion of streptokinase were analyzed. Patients with successful recanalization of infarct vessel and a time lag between onset of symptoms and reperfusion less than 4 hours were assembled in group A1 (n = 15) and patients with successful recanalization but a time lag of more than 4 hours (n = 17) in group A2. Group B consisted of 7 patients with unsuccessful thrombolysis. Coronary anatomy, left ventricular volume, ejection fraction and regional ejection fraction of infarct area were determined before and 4 weeks after thrombolysis with cineangiography. Serum creatine kinase activity was serially measured. Before intervention, the groups were comparable with regard to age, Killip class, localization of infarction, incidence of previous infarction, Gensini score of coronary anatomy, left ventricular volume, ejection fraction, regional ejection fraction of infarct area and serum creatine kinase activity. Four weeks after the intervention, patients in group A1 had a higher ejection fraction (59 %) and regional ejection fraction of infarct area (39%) than patients in group A2 (ejection fraction: 49%, p Thus, contraction of infarct area was improved and enzymatic estimate of infarct size was reduced after early as compared with late reperfusion in patients with acute myocardial infarction.

Effects of verapamil and propranolol on left ventricular systolic function and diastolic filling in patients with coronary artery disease: radionuclide angiographic studies at rest and during exercise.

Abstract: To determine the effects of verapamil on left ventricular (LV) systolic function and diastolic filling in patients with coronary artery disease (CAD), we performed gated radionuclide angiography at rest and during exercise in 16 symptomatic patients before and during oral verapamil therapy (480 mg/day). Twelve patients were also studied during oral propranolol (160--320 mg/day). LV ejection fraction at rest was normal in 13 patients, but abnormal diastolic filling at rest, defined as peak filling rate (PFR) less than 2.5 end-diastolic volumes (EDV)/sec or time to PFR greater than 180 msec, was present in 15. During verapamil, resting ejection fraction decreased (control 50 +/- 10% [+/- SD), verapamil 45 +/- 12%, p less than 0.005), but resting diastolic filling improved: PFR increased (control 1.9 +/- 0.6 EDV/sec, verapamil 2.3 +/- 0.9 ECV/sec, p less than 0.005) and time to PFR decreased (control 185 +/- 38 msec, verapamil 161 +/- 27 msec, p less than 0.05). Exercise ejection fraction did not change during verapamil (control 42 +/- 13%, verapamil 43 +/- 12%, NS), but exercise PFR increased (control 3.1 +/- 0.9 EDV/sec, verapamil 3.6 +/- 1.1 EDV/sec, p less than 0.05) and exercise time to PFR decreased (control 108 +/- 30 msec, verapamil 91 +/- 17 msec, p less than 0.05). In contrast, propranolol did not alter ejection fraction, PFR, or time to PFR at rest or during exercise. Thus, LV ejection fraction is decreased by verapamil at rest but is unchanged during exercise. While LV systolic function is not improved by verapamil, LV diastolic filling is enhanced by verapamil, both at rest and during exercise. These mechanisms may account in part for the symptomatic improvement in many patients during verapamil therapy.

Two-dimensional echocardiographic assessment of left ventricular volumes and ejection fraction in children.

Abstract: The ability of two-dimensional echocardiography to measure left ventricular volumes and ejection fraction was evaluated in 25 children with congenital heart disease. Dimensions and planimetered areas were obtained in the short-axis view at the mitral valve and high and low papillary muscle levels and in the apical two- and four-chamber views. Eight algorithms using five geometric models were assessed. Left ventricular end-diastolic volume, end-systolic volume and ejection fraction were compared with data from biplane cineangiocardiograms. The correlation varied with the algorithm used. Algorithms using short-axis views appeared superior to those using only apical long-axis views. Four algorithms estimated left ventricular volumes with equal accuracy (Simpson's rule, assuming the ventricle to be a truncated cone; Simpson's rule, assuming the ventricle to be a truncated ellipse; hemisphere cylinder; and ellipsoid biplane). The single algorithm that best estimated left ventricular ejection fraction was the ellipsoid biplane formula using the short-axis view at the papillary muscle level (r = 0.91, slope = 0.94, SEE = 6.7%). Thus, two-dimensional echocardiography can accurately assess left ventricular volumes and ejection fraction in children with congenital heart disease.

Prognostic significance of angiographically documented left ventricular aneurysm from the Coronary Artery Surgery Study (CASS).

Abstract: In order to evaluate the prognosis of medically treated patients with angiographically defined left ventricular aneurysm the data available from 1,136 patients with aneurysm (7.6 percent) from 15,019 patients with coronary artery disease in the Coronary Artery Surgery Study (CASS) registry were analyzed. Prior myocardial infarction, reduced ejection fraction, absence of angina and evidence of congestive heart failure were more commonly present in patients with aneurysm. The cumulative survival rates of medically treated patients at 1, 2, 3 and 4 years were 90, 84, 79 and 71 percent, respectively. The Cox analysis of survival indicated that the following variables predicted outcome: age, residual left ventricular function as assessed with angiography, left ventricular end-diastolic pressure, functional impairment due to congestive heart failure, number of vessels diseased, mitral regurgitation and S3 gallop. When survival was stratified for similar degrees of left ventricular dysfunction and functional impairment there was no difference between the survival of patients with aneurysm and that of registry patients without aneurysm. The data from this large population study indicate that the survival of patients with left ventricular aneurysm is better than previously recognized. The mortality in this group is primarily related to age, left ventricular function and clinical severity of heart failure. The presence of an aneurysm does not independently alter survival.

Hemodynamic correlates of right ventricular ejection fraction measured with gated radionuclide angiography.

Abstract: Right ventricular function was studied in 60 patients with equilibrium gated radionuclide angiography. The mean (± standard deviation) right ventricular ejection fraction in 20 normal subjects was 53 ± 6 percent, a value in agreement with previous data from both radionuclide and contrast angiographie studies. This value was similar (55 ± 7 percent) in 11 patients with coronary artery disease but normal left ventricular function. Radionuclide measurements of right ventricular ejection fraction were correlated with right heart hemodynamics. There was a significant negative linear correlation between right ventricular ejection fraction and mean pulmonary arterial pressure (r = −0.82) and between right ventricular ejection fraction and right ventricular end-diastolic pressure (r = −0.67). Furthermore, patients with elevated right ventricular enddiastolic pressure and mean pulmonary arterial pressure had a more severely depressed ejection fraction than did those with an elevated mean pulmonary arterial pressure alone. Thus, an abnormal value for right ventricular ejection fraction by gated radionuclide angiography in the absence of primary right ventricular volume overload suggests abnormal right heart pressures, whereas a normal value excludes severe pulmonary arterial hypertension or an elevated right ventricular end-diastolic pressure.

Inotropic contractile reserve: A useful predictor of increased 5 year survival and improved postoperative left ventricular function in patients with coronary artery disease and reduced ejection fraction

Abstract: The increase in left ventricular ejection fraction produced by postextrasystolic potentiation or epinephrine infusion has been used to demonstrate inotropic contractile reserve in patients with coronary artery disease and a depressed ejection fraction (less than 0.50). Prior studies have shown that a change in ejection fraction of 0.10 or more after postextrasystolic potentiation or epinephrine infusion is helpful in discriminating those patients with a better short-term (1 year) prognosis whether treated medically or surgically. This study related inotropic contractile reserve to 5 year prognosis in 54 patients receiving postextrasystolic potentiation or epinephrine infusion between 1971 and 1974. Current left ventricular function in surviving patients was assessed with radionuclide ventriculograms whenever possible. Five year survival was significantly better in patients with an initial change in ejection fraction greater than 0.10 in both the surgically treated group (16 of 20 versus 5 of 15, p less than 0.01) and the medically treated group (6 of 8 versus 1 of 11, p less than 0.01). Furthermore, among the surviving patients in the surgical group, current ejection fraction in the radionuclide ventriculogram was significantly greater in patients who demonstrated inotropic contractile reserve in their 1971 to 1974 contrast left ventriculogram. These findings support the concept that coronary revascularization enhances function of ischemic but viable myocardium.

Angiographic findings 1 month after myocardial infarction: a prospective study of 259 survivors.

Abstract: Coronary anatomy as it relates to left ventricular function was assessed prospectively in patients who survived acute myocardial infarction. The study population included 259 consecutive male patients age 60 years or younger who underwent catheterization 30 days after the acute event. Coronary artery obstructive lesions (greater than 50% reduction in luminal diameter) were found in 241 patients (93%), 118 (45%) of whom had total and 76 (29%) subtotal (greater than 90%) stenosis) occlusion of at least one coronary artery. Normal coronary vessels were seen in eight patients (3%) and nonobstructive lesions in 10 (4%). One-, two- and three-vessel disease were present in 89, 86 and 66 patients, respectively. Patients with normal coronary arteries or nonobstructive lesions had higher ejection fractions than those with obstructive lesions in one, two or three vessels (p less than 0.05). Ejection fraction was lower (p less than .001) and the percentage of akinetic segments higher (p less than 0.001) in patients with total or subtotal lesions and no collaterals. Adequate collaterals, seen in 29 patients (11%), significantly improved regional wall motion (p less than 0.05) and decreased the percentage of akinetic segments (p less than 0.001). Thus, in a substantial number of patients (32% in our series), the infarcted area is spontaneously reperfused by collaterals or through the involved artery. Both mechanisms ameliorate wall motion in corresponding areas.

Hemodynamic effects of acute atrioventricular sequential pacing in patients with left ventricular dysfunction

Abstract: Acute atrioventricular (A-V) sequential pacing was compared with ventricular pacing in seven men with symptomatic left ventricular failure (New York Heart Association functional class III and IV) and depressed left ventricular ejection fraction (mean 29 percent, range 18 to 40). Cardiac index was higher during A-V sequential pacing than during ventricular pacing for every patient at paced rates of 75 to 100 beats/min. The mean increment was 17 percent (range 10 to 37) at a paced rate of 75 beats/ min, 23 percent (range 8 to 45) at a paced rate of 85 beats/min and 29 percent (range 19 to 55) at a paced rate of 100 beats/min. The increase in cardiac index in an individual patient did not correlate with baseline characteristics including functional class, cardiothoracic ratio, resting ejection fraction, cardiac index or balloon-occluded pulmonary wedge pressure. Arterial pressure varied from beat to beat during ventricular pacing because of the changing relation of atrial to ventricular systole. When an atrial contraction preceded a ventricular paced beat by a physiologic interval intraarterial pulse pressure uniformly increased. That increase correlated strongly (r = 0.993) with the increase in cardiac index that occurred during A-V sequential pacing. Measurement of the pulse pressure during A-V dissociation is a simple technique that may be useful for predicting the degree of improvement in cardiac output expected with methods of pacing that restore A-V synchrony.

Mortality related to cardiac catheterization and angiography.

Abstract: During a 14-month period, 75 deaths occurring in relation to 53,581 cardiac catheterizations were consecutively and prospectively reported to the Registry Committee of the Society for Cardiac Angiography. Three of the patients died several days after their catheterization from an unrelated cause and are excluded from this analysis. There were 21 patients (group I) who arrived at the laboratory in extremis and whose deaths were expected irrespective of the catheterization. Most of these patients suffered from recent myocardial infarctions and cardiogenic shock, or had complex congenital malformations. In 35 patients (group II), a cardiovascular complication occurring during the catheterization resulted in death. In 16 patients (group III) catheterization seemed uneventful, but death occurred suddenly 10 min to 10 h after the procedure. Of these 16 patients, eight had left main coronary artery obstruction greater than or equal to 90%, five had three-vessel disease all with 90% obstructions, one had 2-vessel disease both with 90% obstructions, and who had critical aortic stenosis. The 51 unexpected deaths (groups II and III) were considered to be causally related to the procedure, a mortality rate of 0.10%. Subsets with an increased mortality rate (M), were patients with: a) left main disease greater than 50% (M = 0.94%); b) ejection fraction less than 30% (M = 0.54%); c) NYHA class III or IV (m = 0.24%); d) age over 60 years (M = 0.23%); or e) three-vessel disease (M = 0.13%). In conclusion, catheterization related mortality occurs mostly in patients with far advanced cardiac disease. Nearly 1/3 of the unexpected deaths occurred suddenly after a seemingly uneventful procedure. Close monitoring after catheterization of patients with similar characteristics (left main disease greater than or equal to 90%, or three-vessel disease all greater than or equal to 90%) might disclose avenues for reducing mortality occurring after catheterization.

Assessment of right ventricular function during supine bicycle exercise after Mustard's operation.

Abstract: Right ventricular (RV) performance during supine bicycle exercise was evaluated by gated equilibrium nuclear angiography in 19 clinically well children with d-transposition of the great arteries (d-TGA), 6.4 +/- 2.7 years after Mustard's operation. Comparisons were made between rest and peak exercise. The mean resting ejection fraction was 44 +/- 12% (range 30-75%) and was unchanged at peak exercise. Eight children had a normal ejection fraction response, whereas 11 children had either no increase or a decrease in ejection fraction. Relative end-diastolic volumes decreased from resting values in all patients who had an abnormal ejection fraction response. Among patients whose ejection fraction increased, the end-diastolic volume increased in three, decreased in four and was unchanged in one at peak exercise. Heart rate increased 84% (range 52-135%) and systolic blood pressure increased 16% (range 0-28%) at peak exercise. There was no correlation between exercise response and age at surgery or interval since surgery. These data indicate that clinically well children after Mustard's procedure may have abnormal right ventricular function under stress, raising concerns about the ability of the right ventricle to function as the systemic ventricle.

Limitations of comparing left ventricular volumes by two dimensional echocardiography, myocardial markers and cineangiography

Abstract: Measurement of left ventricular volume at end-diastole or end-systole with both two dimensional echocardiography and either Cineangiography or radionuclide scans, not recorded simultaneously, has shown large echocardiographic underestimation of volumes even in normal ventricles. In this study fluoroscopic and two dimensional echocardiographic recordings were obtained in 18 patients with abnormal wall motion and previously implanted myocardial markers. The echocardiographic values for volume and those derived from myocardial markers correlated well (r = 0.87), and there were no statistically significant differences in values obtained with the two methods at end-diastole or end-systole. The ejection fractions obtained with two dimensional echocardiography (mean ± standard deviation 46 ± 7 percent) and with fluoroscopic recording of the markers (41 ± 9 npercent) did not differ statistically. These results were compared with those in another 18 patients (nine with abnormal wall motion) having two dimensional echocardiography within 24 hours of a 30 ° right anterior oblique contrast left ventriculogram. Again, two dimensional echocardiographic ventricular volume correlated well with the angiographic volume (r = 0.85), although echocardiographic end-diastolic volume was consistently 20 percent less than angiographic end-diastolic volume (p Probable reasons for the lack of severe underestimation of volume with echocardiography even in very abnormal ventricles, relative to that demonstrated in prior reports, include improvements in ultrasonic beam width, tracing method, transducer position and scan plane orientation within the ventricle. In addition, the possible effects of angiographic dye in the ventricular trabeculae are discussed and the effect of simultaneous studies by two different methods are compared.

Prognosis of asymptomatic or mildly symptomatic patients with coronary artery disease.

Abstract: One hundred forty-seven asymptomatic or mildly symptomatic patients with coronary artery disease, who did not have significant left main coronary occlusion and had an ejection fraction greater than 20 percent, were followed up prospectively for 6 to 67 months (average 25). Significant obstruction of one coronary artery was present in 28 percent of patients, of two coronary arteries in 31 percent and of three coronary arteries in 41 percent. Ejection fraction was 55 percent or greater in 69 percent of patients. During the follow-up period there were eight deaths (annual mortality rate 3 percent for the entire group, 1.5 percent for patients with single and double vessel disease but 6 percent for those with triple vessel disease). Better definition of high and low risk subgroups of patients with three vessel disease was accomplished with exercise testing. Despite a history of mild symptoms, 25 percent of the patients with triple vessel disease exhibited poor exercise capacity on exercise testing after administration of beta adrenoceptor blocking agents and nitrates was discontinued; of these, 40 percent either died (20 percent) or had progressive symptoms requiring operation (20 percent) (annual mortality rate 9 percent). Of the patients with good exercise capacity, only 22 percent either died (7 percent) or had progressive symptoms (15 percent) (annual mortality rate 4 percent). Thus, prognosis is excellent in patients with no or mild symptoms who have one or two vessel coronary disease. Patients with three vessel disease who have good exercise capacity documented by objective testing have an annual mortality rate of 4 percent. However, because patients with three vessel disease and poor exercise capacity have an extremely grave prognosis, it would appear reasonable to recommend coronary bypass surgery for this subgroup, even in the absence of supporting data derived from a definitive randomized study.