Showing papers on "Ejection fraction published in 1984"

Profound but Reversible Myocardial Depression in Patients with Septic Shock

Abstract: To characterize the role of cardiac function in septic shock, serial radionuclide cineangiographic and hemodynamic evaluations were done on 20 patients with documented septic shock. Although all patients had a normal or elevated cardiac index, 10 patients had moderate to severe depression of their ejection fraction with values below 0.40. Thirteen of twenty patients survived their episode. Paradoxically, 10 of 13 survivors, but none of the 7 nonsurvivors, had an initial ejection fraction less than 0.40 (p less than 0.005). The mean initial ejection fraction for the survivors was 0.32 +/- 0.04, and their mean end systolic and end diastolic ventricular volumes were substantially increased with a normal stroke volume. The survivors' serial scans showed a gradual return to normal ejection fraction and ventricular volume by 10 days after the onset of shock. Nonsurvivors had normal initial ejection fractions and ventricular volumes that did not change during serial studies.

Exercise cardiac output is maintained with advancing age in healthy human subjects: cardiac dilatation and increased stroke volume compensate for a diminished heart rate.

Abstract: To assess the effect of age on cardiac volumes and function in the absence of overt or occult coronary disease, we performed serial gated blood pool scans at rest and during progressive upright bicycle exercise to exhaustion in 61 participants in the Baltimore Longitudinal Study of Aging. The subjects ranged in age from 25 to 79 years and were free of cardiac disease according to their histories and results of physical, resting and stress electrocardiographic, and stress thallium scintigraphic examinations. Absolute left ventricular volumes were obtained at each workload. There were no age-related changes in cardiac output, end-diastolic or end-systolic volumes, or ejection fraction at rest. During vigorous exercise (125 W), cardiac output was not related to age (cardiac output [1/min] = 16.02 + 0.03 [age]; r = .12, p = .46). However, there was an age-related increase in end-diastolic volume (end-diastolic volume [ml] = 86.30 + 1.48 [age]; r = .47, p = .003) and stroke volume (stroke volume [ml] = 85.52 + 0.80 [age]; r = .37, p = .02), and an age-related decrease in heart rate (heart rate [beats/min] = 184.66 - 0.70 [age]; r = -.50, p = .002). The dependence of the age-related increase in stroke volume on diastolic filling was emphasized by the fact that at this high workload end-systolic volume was higher (end-systolic volume [ml] = 3.09 + 0.65 [age]; r = .45, p = .003) and ejection fraction lower (ejection fraction = 88.48 - 0.18 [age]; r = -.33, p = .04) with increasing age. These findings indicate that although aging does not limit cardiac output per se in healthy community-dwelling subjects, the hemodynamic profile accompanying exercise is altered by age and can be explained by an age-related diminution in the cardiovascular response to beta-adrenergic stimulation.

Congestive heart failure with normal systolic function

Abstract: Although there have been isolated reports of congestive heart failure (CHF) with normal systolic function, the prevalence and characteristics of this condition have not previously been described. Accordingly, 188 patients with CHF undergoing radionuclide ventriculography were prospectively evaluated. Sixty-seven (36%) had a normal ejection fraction (EF) of 0.45 or greater, and 121, an abnormal EF of less than 0.45. Of these, 72 (55 with an abnormal EF [group I] and 17 with a normal EF [group II]) were also reviewed for clinical characteristics. There was no demographic difference between groups, except that systemic hypertension appeared to be a contributing factor in 65% of the patients in group II, compared with 23% of the patients in group I (p

Abnormal left ventricular filling: an early finding in mild to moderate systemic hypertension.

Abstract: This study was undertaken to determine the prevalence and significance of diastolic left ventricular (LV) dysfunction in mild to moderate systemic hypertension. Rest and exercise equilibrium blood pool scintigraphy was performed in 39 hypertensive subjects (mean systolic blood pressure [BP] 156 ± 14 mm Hg [± standard deviation];mean diastolic BP 103 ± 5 mm Hg ) and 11 normal control subjects. These studies were analyzed for ejection fraction (EF), segmental wall motion, peak filling rate (PFR), time to PFR and filling fraction in the first third of diastole normalized for cycle length (first-third filling fraction). EF at rest was similar in the hypertensive patients and control subjects (0.63 ± 0.09 versus 0.65 ± 0.07);only 2 patients had a reduced EF. The EF response to exercise was normal in every hypertensive patient (increasing to a mean of 0.74 ± 0.08);only 1 patient had asynergy. In contrast, even when the 2 patients with abnormal systolic function were excluded, each index of diastolic filling was significantly different from the control group. PFR was lower (2.29 ± 0.49 vs 2.63 ± 0.39 end-diastolic volumes per second [EDV/s], p These findings indicate that diastolic abnormalities may be an early finding in hypertensive heart disease and that they are, at least in part, related to the degree of LV hypertrophy.

Factors influencing the one-year mortality of dilated cardiomyopathy.

Abstract: This study was designed to determine prognostic risk indicators of nonischemic dilated cardiomyopathy (DC). Sixty-nine patients were studied. Each patient underwent physical examination (including a history), electrocardiography, echocardiography, cardiac catheterization, 24-hour monitoring and endomyocardial biopsy. The mortality rate at 1 year was 35% (24 deaths). Univariate analysis revealed that the most powerful predictor of prognosis was the left intraventricular conduction delay (p = 0.003). The pulmonary capillary wedge pressure was also predictive of mortality (p = 0.005). Other significant factors, in order of importance, were ventricular arrhythmias (p = 0.007), mean right atrial pressure (p = 0.008), angiographic ejection fraction (p = 0.03), atrial fibrillation or flutter (p = 0.01) and the presence of an S3 gallop (p = 0.05). Factors such as duration of symptoms, presence of mitral regurgitation, end-diastolic diameter, myocardial cell size and percent fibrosis in the biopsy and treatment with vasodilators, antiarrhythmic and anticoagulant drugs were not significant predictors. Multivariate analysis was used to determine which combination of factors could most accurately predict survival and death. The most important factors were left conduction delay, ventricular arrhythmias and mean right atrial pressure. An equation was derived that can be applied to the prognosis of patients with DC. Thus, the clinical assessment of patients with DC can accurately predict the probability of surviving or dying in 1 year.

Significance of ventricular arrhythmias in idiopathic dilated cardiomyopathy.

Abstract: The incidence and prognostic significance of ventricular arrhythmias identified by 24-hour ambulatory electrocardiography (Holter) was prospectively assessed in 74 patients with idiopathic dilated cardiomyopathy (IDC). The criteria for diagnosis of IDC were based on clinical and cardiac catheterization findings. Holter monitoring was performed at the time of entry into the study. Patients were followed for 2 to 21 months (mean 11 +/- 3). Frequent ventricular premature complexes (VPCs) (greater than 1,000/24 hours) were seen in 35%, and complex VPCs (Lown grade III and IV) in 87% of the patients. Forty-nine percent of the patients had nonsustained ventricular tachycardia (VT) consisting of 3 to 32 beats with rates from 110 to 230 beats/min, and 20% had ventricular pairs. No correlation was found between clinical symptoms or the degree of left ventricular (LV) impairment and the number of ventricular pairs or episodes of VT. During follow-up, 19 patients died, 7 from congestive heart failure (CHF) and 12 suddenly. Patients who died suddenly had significantly more episodes of VT, ventricular pairs or total VPCs (p less than 0.01 each) compared with survivors and those who died from CHF. No significant differences were found between patients who died from CHF or suddenly with respect to LV end-diastolic pressure, LV end-diastolic volume index, LV ejection fraction (EF) and cardiac index. A linear stepwise discriminant function analysis using hemodynamic (LVEF and cardiac index) and arrhythmic (number of VT episodes and ventricular pairs) variables resulted in a meaningful separation between survivors and patients who died from CHF or suddenly.(ABSTRACT TRUNCATED AT 250 WORDS)

Relation of right ventricular ejection fraction to exercise capacity in chronic left ventricular failure

Abstract: Although the left ventricle is traditionally viewed as the heart's main pumping chamber, no correlation has been shown between left ventricular (LV) ejection fraction (EF) at rest and exercise capacity in patients with chronic LV failure. Because vasodilators with venodilating activity increase exercise capacity more than predominant arterial dilators in patients with LV failure, right ventricular (RV) function may relate to exercise capacity in these patients. In 25 patients with chronic LV failure, caused by coronary artery disease in 12 patients and idiopathic dilated cardiomyopathy in 13 patients, RVEF and LVEF at rest were measured by radionuclide angiography. Maximal upright bicycle exercise testing was also performed to determine maximal oxygen consumption, which averaged only 13 +/- 4 ml/min/kg. The LVEF at rest was 26 +/- 10% and did not correlate with maximal oxygen consumption (r = 0.08). However, the RVEF was 41 +/- 12% and correlated with maximal oxygen consumption (r = 0.70, p less than 0.001) in the same patients. The correlation was stronger (r = 0.88) in patients with coronary artery disease than in those with idiopathic dilated cardiomyopathy (r = 0.60). Thus, RVEF at rest is more predictive of exercise capacity than LVEF in the same patients with chronic LV failure. These results are consistent with the clinical observation that only venodilating agents increase exercise capacity of patients with chronic LV failure.

Selective impairment of baroreflex-mediated vasoconstrictor responses in patients with ventricular dysfunction.

Abstract: Cardiac dysfunction in animals has been associated with impairment of arterial and cardiopulmonary baroreflex control of the circulation. Chronic heart failure in human beings is associated with neurohumoral excitation, which could result in part from impairment in the inhibitory influence of baroreflexes. We postulated that (1) patients with left ventricular dysfunction (LVD) have impaired baroreflex modulation of vascular resistance and (2) administration of a digitalis glycoside would immediately restore baroreflex sensitivity. Eleven patients with LVD (NYHA class, 2.8 +/- 0.2, mean +/- SEM; baseline left ventricular ejection fraction, 18 +/- 2%; cardiac index, 2.4 +/- 0.21/min/m2; and pulmonary capillary wedge pressure, 26.0 +/- 3.2 mm Hg) were compared with 17 normal control subjects. We measured forearm vasoconstrictor responses to simulated orthostatic stress with use of lower body negative pressure (LBNP) at -10 and -40 mm Hg to unload cardiopulmonary and arterial baroreceptors. Baseline forearm vascular resistance (FVR) was higher in patients with LVD than in normal subjects: FVRLVD, 68.8 +/- 15.3 U; FVRN, 23.2 +/- 2.1 U (p less than .001). During unloading of baroreceptors with LBNP -10 mm Hg, normal subjects developed vasoconstriction (delta VRN at LBNP -10 mm Hg, +5.7 +/- 1.6 U) but patients with LVD failed to have vasoconstriction and tended to develop vasodilation (delta FVRLVD at LBNP -10 mm Hg, -8.6 +/- 8.5 U) (p = .05, normals vs patients with LVD at LBNP -10 mm Hg). A more marked disparity in response was seen during unloading of baroreceptors of LBNP -40 mm Hg: delta FVRN at LBNP -40 mm Hg, +16.6 +/- 1.5 U; delta FVRLVD at LBNP -40 mm Hg, -10.3 +/- 9.6 U (p less than .001, normals vs patients with LVD). Despite high baseline values for FVR, patients with LVD developed vasoconstriction during intra-arterial infusions of norepinephrine, thereby excluding a nonspecific depression of vascular reactivity as the mechanism for abnormal responses to LBNP in patients with LVD. We also studied the short-term effects of administration of a digitalis glycoside, ouabain 0.0075 mg/kg (seven patients) or lanatoside C (Cedilanid-D) 0.02 mg/kg (three patients), on baroreflex-mediated vasoconstrictor responses to LBNP in the patients with LVD. Digitalis glycoside reduced baseline FVR from 71.8 +/- 16.6 to 48.6 +/- 12.0 U (p less than .02). Responses to LBNP tended to be normalized after administration of digitalis glycoside: delta FVR during LBNP -40 mm Hg, -11.1 +/- 10.5 U before and +7.8 +/- 5.6 U after the drug (p less than .05).(ABSTRACT TRUNCATED AT 400 WORDS)

Left ventricular mural thrombi complicating acute myocardial infarction. Long-term follow-up with serial echocardiography.

Abstract: To determine the clinical significance of left ventricular thrombi, we used two-dimensional echocardiography to study 261 patients with acute transmural myocardial infarction. Mural thrombi were found in 46 patients. This complication occurred in 34% (44 of 130) of anterior wall infarctions but in only 1.5% (2 of 131) of inferior wall infarctions. An apical wall motion abnormality was present in all patients with thrombus. Severe depression of left ventricular function was not a prerequisite for thrombus formation: the mean left ventricular ejection fraction was 37 +/- 1.5%. Forty-three patients with left ventricular thrombi were followed for a mean duration of 15 months with serial echocardiography. None of the 25 patients who received anticoagulation treatment had an embolic event. Embolization occurred in 7 of 18 patients who had not received anticoagulation treatment. All embolic events occurred within 4 months of infarction. Although anticoagulation treatment appeared to provide protection against embolic events, the prevalence of left ventricular thrombi on follow-up echocardiographic study was essentially the same whether or not this treatment was used.

Functional left ventricular aneurysm formation after acute anterior transmural myocardial infarction: incidence, natural history and prognostic implications

Abstract: To assess the clinical and prognostic importance of the early appearance of a functional left ventricular aneurysm after myocardial infarction, we used equilibrium radionuclide angiocardiography to study 51 patients with an initial anterior infarction. A functional aneurysm was defined as an area of systolic akinesis or dyskinesis with a distinct diastolic deformity and preserved adjacent wall motion. Functional aneurysms developed in 18 patients (Group 1). Left ventricular ejection fraction was comparable in this group and in the 33 patients without aneurysm (Group 2) (27.3 +/- 10 vs. 31.4 +/- 12 per cent). One-year mortality was markedly different, with 11 deaths (61 per cent) in Group 1 and 3 (9 per cent) in Group 2 (P less than 0.001). Six (55 per cent) of the deaths in Group 1 were sudden. Patients with a functional aneurysm appearing within 48 hours had the highest risk of dying (8 of 10). Thus, early formation of a functional aneurysm occurs frequently after anterior myocardial infarction and carries a high risk of death within one year that is independent of ejection fraction. In addition, the absence of a functional aneurysm identifies a large group with a low one-year mortality despite a markedly impaired ejection fraction.

Physiologic Abnormalities of Cardiac Function in Progressive Systemic Sclerosis with Diffuse Scleroderma

Abstract: To investigate cardiopulmonary function in progressive systemic sclerosis with diffuse scleroderma, we studied 26 patients with maximal exercise and redistribution thallium scans, rest and exercise radionuclide ventriculography, pulmonary-function testing, and chest roentgenography. Although only 6 patients had clinical evidence of cardiac involvement, 20 had abnormal thallium scans, including 10 with reversible exercise-induced defects and 18 with fixed defects (8 had both). Seven of the 10 patients who had exercise-induced defects and underwent cardiac catheterization had normal coronary angiograms. Mean resting left ventricular ejection fraction and mean resting right ventricular ejection fraction were lower in patients with post-exercise left ventricular thallium defect scores above the median (59 +/- 13 per cent vs. 69 +/- 6 per cent [P less than 0.025], and 36 +/- 12 per cent vs. 47 +/- 7 per cent [P less than 0.025], respectively). We conclude that in progressive systemic sclerosis with diffuse scleroderma, abnormalities of myocardial perfusion are common and appear to be due to a disturbance of the myocardial microcirculation. Both right and left ventricular dysfunction appear to be related to this circulatory disturbance, suggesting ischemically mediated injury.

A comparison of cardiac biopsy grades and ejection fraction estimations in patients receiving Adriamycin.

Abstract: One hundred fifty-eight patients receiving Adriamycin underwent 226 transjugular biopsy procedures. The specimens were evaluated by electron microscopy for evidence of drug-related cardiotoxicity. Ejection fraction determinations using echocardiographic or nuclear techniques at rest were available for 69% and 81% of the patients, respectively. Analysis of the data revealed a correlation between cumulative Adriamycin dose and biopsy grade (p less than 0.02). No similar relationship existed between cumulative Adriamycin dose and ejection fractions obtained at rest or between biopsy grades and ejection fractions. In patients who underwent serial endomyocardial biopsies and serial ejection fraction determinations, the correlation between changes in biopsy grade and ejection fraction was poor. A change in resting ejection fraction detected by either method did not reliably predict a change in biopsy grade. The poor correlation between ejection fractions and biopsy grades could be due in part to the sensitivity and specificity of the Adriamycin-related structural changes in contrast to the wider range of disease processes that can affect myocardial function, and to the fact that structural changes often precede the ejection fraction abnormalities. The greater sensitivity and specificity of the biopsy grade should prove useful in reducing the risks associated with evaluating new anthracyclines and potential myocardial protectors of Adriamycin toxicity.

Prognostic indicators from radionuclide angiography in medically treated patients with coronary artery disease

Abstract: The purpose of this investigation was to determine which variables obtained when performing radionuclide angiography predict subsequent survival or total events (cardiovascular death or nonfatal myocardial infarction) in stable patients with symptomatic coronary artery disease (CAD). Univariable and multivariable analyses of 6 variables, including ejection fraction (EF) at rest and exercise, change in EF with exercise, development of ischemic chest pain or electrocardiographic changes, left ventricular (LV) wall motion abnormalities and exercise time were examined in 386 patients followed up to 4.5 years. Univariate analyses revealed that the exercise EF was the variable most closely associated with future events (p less than 0.01), followed by EF at rest, wall motion abnormalities and exercise time. Multivariable analyses revealed that once the exercise EF was known, no other radionuclide variables contributed independent information about the likelihood of future events. Multivariable analyses also revealed that the exercise EF describes much of the prognostic information of coronary anatomy. Our findings suggest that the radionuclide angiogram is useful in predicting future events in patients with stable CAD, although examination in conjunction with other clinical descriptors will be necessary to further quantify this contribution.

Prognosis of patients with diabetes mellitus after acute myocardial infarction.

Abstract: Sixty patients with diabetes mellitus who survived the coronary care unit phase of acute myocardial infarction (AMI) were followed an average of 19 months and the prognosis of diabetic patients was compared with that of 719 nondiabetic patients. The mortality rate was 25% in diabetic patients and 8% in nondiabetic patients. These patients had been entered in a Multicenter Postinfarction Program, where analysis of the total data base showed 4 significant prognostic factors: cardiac symptoms before AMI, pulmonary rales when the patient was in the coronary care unit, more than 10 ventricular premature complexes per hour recorded on Holter monitor just before discharge, and a radionuclide ejection fraction of less than 40%. Of these 4 factors, only cardiac symptoms before AMI was significantly more common in diabetic patients (57% in diabetic vs 36% in nondiabetic patients). When each of these 4 factors was stratified for severity, the mortality rate was always higher in diabetic patients. The data were examined to determine other factors in diabetic patients who died. Pulmonary rales was significantly more common in diabetic patients who died (6% in survivors vs 42% in patients who died). In a multivariate analysis of both diabetic and nondiabetic patients, 5 factors were significant determinants of prognosis. They are, in order of entry into the model, rales (p

Regression of left ventricular hypertrophy from systemic hypertension by enalapril.

Abstract: Reversal of left ventricular (LV) hypertrophy with medical therapy has been studied increasingly in patients with systemic hypertension. However, serial changes of LV function are not found during reversal of LV hypertrophy in hypertensive patients. Seven patients with LV hypertension were studied to evaluate serial changes of LV mass and function after the initiation of the new converting enzyme inhibitor MK-421. LV mass and function were determined serially at the end of a placebo period and at 5 days, 1 month, 3 months and 7 months after the initiation of MK-421, using both 2-dimensional (2-D) guided M-mode echocardiography and radionuclide techniques. All patients except 1 had LV hypertrophy and all had normal LV function (ejection fraction derived from gated blood pool method greater than 49%). There was an inverse relation between LV fractional shortening (percent FS) and end-systolic stress before medication (r = -0.81, p less than 0.05). LV mass decreased significantly at 3 months and at 7 months (-10%, p less than 0.05, and -12%, p less than 0.01, respectively) accompanied with persistent decrease of mean blood pressure, which occurred as early as 5 days after start of therapy (133 +/- 5 mm Hg at control, to 112 +/- 4 mm Hg at day 5). During reversal of LV hypertrophy, the inverse correlation between FS and end-systolic stress remained significant (r = -0.80 to -0.95, p less than 0.025 for all), with no difference from the placebo period and from this relation in the normal group. Moreover, percent FS, ejection fraction and stroke index remained unchanged. Thus, LV hypertrophy in patients with systemic hypertension can be reversed without deterioration of LV function. Moreover, overall LV function is likely to be determined by afterload even after reversal of LV hypertrophy.

Exercise-induced ischemia in mildly symptomatic patients with coronary-artery disease and preserved left ventricular function. Identification of subgroups at risk of death during medical therapy.

Abstract: To determine prospectively whether the severity of reversible left ventricular ischemia provides prognostic information in mildly symptomatic patients with coronary-artery disease and preserved left ventricular function at rest (ejection fraction greater than 40 per cent), we studied 117 patients by means of exercise electrocardiography and radionuclide angiography. No patient had stenosis of the left main coronary artery. Mortality during subsequent medical therapy was significantly associated (by univariate life-table analysis) with three-vessel coronary-artery disease and the magnitude of the ejection fraction during exercise. In patients with three-vessel disease who had both ST-segment depression of 1 mm or more and a decrease in ejection fraction during exercise, in association with an exercise tolerance of 120 W or less, the probability of survival at four years was only 71 +/- 11 per cent (S.E.). All deaths occurred in this subgroup. Thus, objective evidence of left ventricular ischemia during exercise and exercise capacity identify one subgroup of minimally symptomatic patients with three-vessel disease with an excellent prognosis and another subgroup at relatively high risk of dying during subsequent medical therapy.

Return of left ventricular function after reperfusion in patients with myocardial infarction: importance of subtotal stenoses or intact collaterals.

Abstract: To determine whether subsequent improvement in left ventricular ejection fraction can be predicted from preintervention coronary arteriograms, we divided 63 patients with acute myocardial infarction into two groups based on findings at emergency coronary arteriography at a mean of 7 hr after onset of symptoms: (1) a "no-flow" group with an occluded infarct-related artery and no easily visible collaterals (n = 36) and (2) a "limited-flow" group with either subtotal stenosis or total occlusion of the infarct-related vessel with intact collaterals (n = 27) Of the 63 patients, 61 underwent emergency procedures to establish reperfusion At follow-up angiography (contrast or radionuclide) performed 12 +/- 7 days after infarction, global ejection fraction had increased significantly in patients with limited flow to the infarct zone and "successful" early reperfusion intervention due primarily to a significant increase in the regional ejection fraction in the infarct zone Global ejection fraction fell significantly between baseline and follow-up in patients with no flow to the infarct zone and "unsuccessful" early reperfusion intervention due primarily to a fall in the regional ejection fraction of the noninfarct zone Global and regional ejection fractions did not change significantly in patients with no flow to the infarct zone and successful early reperfusion or in patients with limited flow to the infarct zone and unsuccessful early reperfusion intervention The elapsed time before reperfusion did not relate significantly to the change in either regional or global ejection fraction However, the magnitude of improvement in both global and regional ejection fraction at follow-up was greater among patients with anterior infarcts than among those with inferior infarcts, possibly because baseline ejection fraction was lower in patients with anterior infarcts These data indicate that among patients with acute myocardial infarction undergoing emergency coronary arteriography at a mean of 7 hr after onset of symptoms, improvement in global ejection fraction is unlikely to occur even after a successful early reperfusion intervention in the absence of preserved flow to the infarct area However, among patients with subtotally occluded infarct-related arteries or significant collateral blood flow to the infarct zone, subsequent improvement in global and regional ejection fraction in the zone of myocardial infarction frequently occurs Improvement in both global and regional ejection fraction may be more readily demonstrated in patients initially having more severe depression of these parameters

Prognosis after recovery from first acute myocardial infarction: Determinants of reinfarction and sudden death☆

Abstract: Factors associated with total cardiac mortality, sudden cardiac death and reinfarction were studied in 325 male survivors aged younger than 60 years of age (mean 50) of a first myocardial infarction (MI). All patients had undergone exercise testing and cineangiocardiography 4 weeks after MI, 24% underwent coronary artery surgery and 30% received β-blocking therapy. Patients were followed 1 to 6 years (mean 3.5). Total cardiac mortality was best predicted by the left ventricular (LV) ejection fraction (EF) and by a coronary prognostic index. In contrast, neither the severity of coronary arterial lesions measured with a scoring system nor the results of the exercise test gave significant prediction of mortality. Of the 2 major late sequelae of MI, reinfarction could not be predicted by any clinical or cineangiocardiographic variable. However, sudden death not associated with reinfarction was significantly more common (p 40%. Comparison of patients with an EF It is concluded that, at least for groups of patients treated with standard modern methods after MI, the main determinant of medium-term survival is the extent of LV damage. The state of the coronary arteries and the presence of ischemic myocardium during exercise are only of secondary importance for survival.

Ventricular arrhythmias in idiopathic dilated cardiomyopathy.

Abstract: Twenty four hour ambulatory electrocardiograms were recorded in 60 patients with idiopathic dilated cardiomyopathy. The diagnosis was based on clinical, laboratory, and cardiac catheterisation findings. All patients had a left ventricular ejection fraction less than 0.55; in 39 it was less than 0.40. Ventricular extrasystoles were evident in all patients: they were rare in 11 (18%), moderately frequent in 24 (40%), and frequent in 25 (42%). Multiform extrasystoles were recorded in 57 patients (95%), paired ventricular extrasystoles in 47 (78%), and non-sustained ventricular tachycardias consisting of three to 19 beats in 25 (42%) of the 60 patients studied. Eight patients had more than five episodes of ventricular tachycardia a day. Patients with atrial fibrillation had the same frequency and grade of ventricular arrhythmias as those with sinus rhythm. Patients with infrequent and frequent ventricular extrasystoles could not be differentiated on the basis of the clinical or haemodynamic findings. The mean values of NYHA functional class, cardiac index, left ventricular end diastolic pressure, and ejection fraction were, however, significantly different in patients with and without ventricular tachycardia. During follow up of 12 +/- 5 months seven patients died; all seven had an ejection fraction less than 0.40. In four patients who died of congestive heart failure, but in only one of the three patients who died a sudden cardiac death, ventricular tachycardia was recorded during ambulatory monitoring. High grade ventricular arrhythmias are often seen in patients with idiopathic dilated cardiomyopathy; patients with ventricular tachycardia have more impairment of left ventricular function than patients without ventricular tachycardia; and ambulatory monitoring may be of little help in identifying patients at increased risk of sudden cardiac death.

The effects of gonadectomy on left ventricular function and cardiac contractile proteins in male and female rats.

Abstract: To examine the influence of the sex hormones on mechanical properties and biochemistry of the adult heart, we studied left ventricular function and cardiac contractile proteins in hearts from 20-week-old male and female rats that had been gonadectomized at 18 days of age, compared with hearts from sham-operated animals. Testosterone and estradiol were not detectable in serum from male and female gonadectomized rats, respectively. The male rats had lower body and heart weights than male sham operated rats, whereas these values were higher in female gonadectomized than in female sham-operated rats. Left ventricular function was studied in a working heart apparatus at similar heart rate and at controlled levels of aortic diastolic pressure and left atrial pressure. At moderate left atrial pressure, end-diastolic pressure and volume per gram dry left ventricle were the same in all groups, but at high left atrial pressure, end-diastolic pressure, and volume per gram dry left ventricle were lower in male and female gonadectomized than in the respective sham-operated rats. Further increases in left atrial pressure were associated with mechanical alternans in male and female gonadectomized rats. Significantly (P less than 0.05) lower values for cardiac output, peak systolic pressure, ejection fraction, and myocardial oxygen consumption occurred in male gonadectomized compared with sham-operated rats at moderate and high left atrial pressure at higher levels of aortic diastolic pressure. Decreases in these values for female gonadectomized compared with sham-operated rats occurred only at high left atrial pressure. A significant downward shift in the mean force-velocity relationship was observed in all gonadectomized rats at both moderate and high left atrial pressure. In a follow-up study, when end-diastolic pressure was kept the same at both moderate and high left atrial pressure in female sham-operated and gonadectomized rats by reducing heart rate, decreases in contractile function in gonadectomized rats were observed at all preloads. Ca++-myosin ATPase activity was significantly reduced by 34% in male and by 19% in female gonadectomized rats when compared to respective sham-operated control hearts. These alterations in myosin ATPase activity were associated with a reduction in the V1 myosin isoenzyme and an increase in the V3 isoenzyme. Thus, left ventricular filling and left ventricular function were impaired in hearts of gonadectomized rats. Alterations in function were associated with depressed cardiac myosin ATPase activity in male and female gonadectomized rats.(ABSTRACT TRUNCATED AT 400 WORDS)

Exercise-induced left ventricular dysfunction in young men with asymptomatic diabetes mellitus (diabetic cardiomyopathy).

Abstract: Radionuclide ventriculographic studies were performed at rest and during exercise on 30 consecutive men, aged 21 to 35 years with diabetes mellitus without evidence of coronary artery or any other cardiovascular disease, and in 20 normal age-matched subjects. Sixteen (53%) were treated with insulin and 14 (47%) were treated with either diet (6 patients) or oral antidiabetic therapy (8 patients). All patients from both groups had normal left ventricular (LV) ejection fraction (EF) at rest. In 5 of the 30 diabetic patients (17%), LVEF decreased after exercise, in 8 (27%) it remained unchanged and in 17 it increased normally. Mean LVEF at rest and after exercise in this group was 66 ± 7% and 72 ± 7% (± standard deviation), respectively. In all normal subjects, LVEF increased after exercise. Mean LVEF at rest and after exercise in the normal group was 66 ± 7% and 76 ±9%, respectively. No patient had evidence of regional dysfunction at rest or after exercise. LV function was not related to serum glucose levels during the test, modality of treatment, insulin dependency or duration of the disease. Three of 4 patients with diabetic microvascular complications showed LV dysfunction. In 4 of 5 patients in whom LVEF decreased after exercise, thallium studies showed normal perfusion. Thus, diabetes mellitus may cause exercise-induced global LV dysfunction in young men with no evidence of cardiovascular disease. This phenomenon apparently does not seem to follow the known course of diabetic microvascular complications.

Global and regional left ventricular function and tomographic radionuclide perfusion: the Western Washington Intracoronary Streptokinase In Myocardial Infarction Trial.

Abstract: The Western Washington Intracoronary Streptokinase In Myocardial Infarction Trial enrolled 250 patients with acute myocardial infarction. After the coronary angiographic diagnosis of thrombosis, patients were randomly assigned to receive either conventional therapy with heparin or intracoronary streptokinase followed by heparin. Of the 232 patients who survived at least 60 days, 207 (89%) underwent radionuclide ventriculographic determination of global and regional ejection fraction at a single institution at 62 +/- 35 days after infarction. In the first 100 patients, infarct size was also determined by quantitative single-photon emission tomographic imaging with thallium-201 (201Tl) and expressed as a percentage of the left ventricle with a perfusion defect. Overall, global ejection fraction did not differ between patients treated with streptokinase (45.9 +/- 13.9%; n = 115) and control patients (46.1 +/- 14.4%; n = 92, p = NS). Similarly, the regional posterolateral, inferior, and anteroseptal ejection fraction did not differ between the two groups. Infarct size as measured by 201Tl tomography was 19.4 +/- 12.8% (n = 52) of the left ventricle for the streptokinase group and 19.6 +/- 11.8% (n = 48; p = NS) for the control group. When patients were compared within groups by electrocardiographic location of infarction, time to treatment, or the presence or absence of vessel opening, there were no significant differences between streptokinase and control patients. Statistical inclusion of the 18 patients who died early and were unavailable for study also failed to modify the results, except for a possible reduction in inferior infarct size as measured by 201Tl tomography.(ABSTRACT TRUNCATED AT 250 WORDS)

Sustained improvement of cardiac function in patients with congestive heart failure after short-term infusion of dobutamine.

Abstract: Fifteen patients with congestive cardiomyopathy (six idiopathic and nine alcoholic) manifested by heart failure (New York Heart Association class III or IV) were randomly assigned to a protocol in which dobutamine (n = 8) or 5% dextrose in water (n = 7) was infused continuously for 72 hr. The dose of dobutamine was titrated to increase cardiac output to twice the baseline values. The patients were evaluated before infusion, shortly after infusion, and 1, 2, and 4 weeks thereafter. Functional class improved in six of eight dobutamine-treated patients but in only two of seven control patients during the 4 week observation period. Maximal exercise time and left ventricular ejection fraction increased significantly above baseline only in the dobutamine group. However, neither dobutamine nor placebo infusion produced significant changes shortly after infusion in heart rate, cardiac index, or total peripheral vascular resistance at rest or during exercise at similar workloads. The group receiving dobutamine did show a reduction in systemic systolic and pulmonary arterial mean and diastolic pressure at rest (123 +/- 5 to 108 +/- 6, 32 +/- 5, to 24 +/- 3, and 26 +/- 4 to 20 +/- 2 mm Hg, respectively). In addition, total body oxygen consumption during similar workloads was lower after dobutamine infusion than before.(ABSTRACT TRUNCATED AT 250 WORDS)

Determinants of survival in patients with congestive cardiomyopathy: quantitative morphologic findings and left ventricular hemodynamics.

Abstract: We analyzed data from 68 consecutive patients with congestive cardiomyopathy to evaluate the prognostic significance of quantitative morphologic findings in left ventricular myocardium as compared with the prognostic significance of left ventricular hemodynamics. Left ventricular endomyocardial biopsy specimens were obtained from all patients during diagnostic heart catheterization. Myocardial fiber diameter, volume fraction of interstitial fibrosis, and intracellular volume fraction of myofibrils were determined by light-microscopic morphometry. All patients had normal coronary arteriograms, but reduced left ventricular ejection fractions. There were 23 deaths during a mean follow-up period of 1124 days. Multivariate regression analysis (Cox model) revealed that left ventricular ejection fraction (p less than .00001) and left ventricular systolic pressure (p less than .01), but not morphometric findings in biopsy specimens, were independent predictors of cardiac death. Thus, morphologic findings in the left ventricular myocardium do not contribute significantly to the prognostic evaluation in patients with congestive cardiomyopathy studied by hemodynamic and angiographic methods.

Comparative value of maximal treadmill testing, exercise thallium myocardial perfusion scintigraphy and exercise radionuclide ventriculography for distinguishing high- and low-risk patients soon after acute myocardial infarction☆

Abstract: The prognostic value of symptom-limited treadmill exercise electrocardiography, exercise thallium myocardial perfusion scintigraphy and rest and exercise radionuclide ventriculography was compared in 117 men, aged 54 ± 9 years, tested 3 weeks after a clinically uncomplicated acute myocardial infarction (MI). During a mean follow-up period of 11.6 months, 8 men experienced “hard” medical events (cardiac death, nonfatal ventricular fibrillation or recurrent MI) and 14 were hospitalized for unstable angina pectoris, congestive heart failure or coronary bypass surgery (total of 22 combined events). By multivariate analysis (Cox proportional hazards model), peak treadmill work load and the change in left ventricular ejection fraction (EF) during exercise were significant (p

Programmed electrical stimulation in patients with high-grade ventricular ectopy: electrophysiologic findings and prognosis for survival.

Abstract: The significance and treatment of ventricular premature beats (VPBs) in patients without sustained ventricular tachycardia (VT), sudden death, or syncope remains unclear. We undertook a prospective study of programmed electrical stimulation (up to two extrastimuli and burst pacing) in 73 patients (age 60 +/- 10 years) with high-grade VPBs who had no evidence of sustained VT, sudden death, or syncope as determined by 48 hr of monitoring in the cardiac care unit and 48 hr Holter monitoring. Fifty-six patients (76.7%) had atherosclerotic heart disease, 10 (13.7%) had cardiomyopathy or valvular heart disease, and seven (9.6%) had no evident heart disease. Thirty-seven patients (50.7%) had Lown grade IVB VPBs, 30 (41.1%) had Lown grade IVA VPBs, and six (8.2%) had Lown grade III VPBs. Programmed electrical stimulation identified two groups of subjects: group 1 comprised 20 patients (27%) in whom VT or ventricular fibrillation was induced, group 2 comprised 53 patients (73%) in whom no ventricular arrhythmia or only two to four repetitive ventricular responses were induced. There was a significant difference between the presence of atherosclerotic heart disease, old myocardial infarction, and ejection fraction of less than 40% in group 1 compared with group 2. However, there was no significant difference in the grade of VPBs between the two groups. Seventeen of 20 patients from group 1 were placed on antiarrhythmic therapy (defined by programmed electrical stimulation), whereas group 2 patients were randomly assigned to prophylactic antiarrhythmic therapy. A total of 70 patients were followed up for 30 +/- 15 months. The incidence of sustained VT and/or sudden death (31.5% vs 2%; p less than .001) was significantly higher in group 1 compared with group 2.(ABSTRACT TRUNCATED AT 250 WORDS)