ISSN:0009-7322    

出版商:OVID    

年代:1984

数据来源: OVID

ISSN:0009-7322    

出版商:OVID    

年代:1984

数据来源: OVID

摘要:

&NA;To assess the relationship of postural changes in blood pressure to risk of myocardial infarction, 1359 men were followed for an average of 8.7 years. The men were participants in the Normative Aging Study, a longitudinal study of aging initiated in 1963 at the Veterans Administration Outpatient Clinic in Boston. It was found that the relationship of sitting blood pressure to the subsequent incidence of myocardial infarction was modified by a variable formed by subtracting supine from standing diastolic blood pressure (&Dgr;DBP). The effect of sitting diastolic blood pressure on risk of myocardial infarction was confined primarily to men with a &Dgr;DBP of 10 mm Hg or more. The effect of sitting systolic blood pressure on risk of myocardial infarction was apparent in all categories of &Dgr;DBP (<1, 1 to 9, ≥10 mm Hg), but the gradient of risk became stronger with increasing levels of &Dgr;DBP. The modifying influence of &Dgr;DBP remained even when standard coronary risk factors were included in multivariate analyses. These findings suggest a relationship of vascular responsiveness to risk of subsequent myocardial infarction and may have clinical utility.Circulation 70, No. 4, 533‐537, 1984.

ISSN:0009-7322    

出版商:OVID    

年代:1984

数据来源: OVID

摘要:

&NA;We analyzed long‐term follow‐up data accumulated during an 8 year study of survivors of prehospital cardiac arrest. All patients included in this study were primary entrants via communitybased rescue systems; patients who were tertiary referrals (survivors of cardiac arrest from other hospitals) were not included in this analysis. In the group of 61 patients entering our study between 1975 and 1980, with a follow‐up to 1983, there have been a total of 24 deaths (39%). Sixteen of the 24 deaths were the result of recurrent cardiac arrest; eight were nonsudden cardiac deaths or noncardiac deaths. The mean duration from entry to death in the nonsurvivors was 27.5 ± 19.7 months, and the time from the index event to last follow‐up in the long‐term survivors was 59.9 ± 19.4 months. Life table analysis demonstrated a 10% rate of recurrence of cardiac arrest in the first year, with a 5% per year rate in each of the subsequent 3 years. Left ventricular ejection fractions at entry were not significantly different between survivors (mean = 45.3 ± 13.6%) and nonsurvivors (mean = 37.6 ± 12.6%), and the severity of ejection fraction abnormality at entry did not correlate with time to death in the nonsurvivors. However, ejection fraction was significantly lower in patients who died from causes other than recurrent cardiac arrest than in those who died of cardiac arrest (24.5 ± 9.1% vs 42.7 ± 9.2%; p < .002). Frequency and Lown classifications of ventricular arrhythmias in patients on longterm antiarrhythmic therapy during follow‐up did not distinguish those patients who were to have recurrent cardiac arrest from those who continued as long‐term survivors. The 10% 1 year and 15% 2 year recurrence rates in survivors of prehospital cardiac arrest, unselected except for exclusion of acute myocardial infarction as a precipitating event, provide a minimum goal for outcome against which risk in various subgroups and effectiveness of other methods of intervention can be measured.Circulation 70, No. 4, 538‐546, 1984.

ISSN:0009-7322    

出版商:OVID    

年代:1984

数据来源: OVID

摘要:

&NA;A group of 916 apparently healthy men between the ages of 27 and 55 years (mean 37) were followed up with serial medical and exercise test evaluations for a period of 8 to 15 years (mean 12.7) to determine (1) the prevalence and specific types of new coronary events observed in subjects with and without abnormal ST segment responses to exercise and (2) the predictive value of a serial conversion to an abnormal ST segment response to exercise for new coronary events. During the initial evaluation there were 23 subjects (2.5%) with an abnormal ST segment response to exercise. During follow‐up there were nine (39%) coronary events in this group: eight cases of angina and one of sudden death. With serial testing, an additional 38 subjects (5.1%) experienced conversion to an abnormal ST segment response to exercise. During follow‐up there were 12 (32%) coronary events in this group: 10 cases of angina, one of myocardial infarction, and one other. There were 833 subjects with normal ST segment responses to exercise with all tests. In this group there were 44 (5.3%) coronary events: 25 cases of myocardial infarction, seven of sudden death, and 12 of angina. We conclude that in apparently healthy middle‐aged men an abnormal ST segment response to exercise is predictive of angina pectoris but not of myocardial infarction or sudden cardiac death as an initial coronary event.Circulation 70, No. 4, 547‐551, 1984.

ISSN:0009-7322    

出版商:OVID    

年代:1984

数据来源: OVID

摘要:

&NA;The purpose of this study was to examine the relationship between maximal O2uptake (&OV0312;O2max) and left ventricular systolic function in patients with coronary artery disease. We studied 27 patients, age 50 ± 10 years (mean ± SD), who were asymptomatic and able to attain true &OV0312;O2max. &OV0312;O2max was defined by the leveling‐off criterion and/or a respiratory exchange ratio of 1.15 or greater. Left ventricular ejection fraction was determined by gated cardiac blood pool imaging. In patients whose ejection fraction decreased with exercise, &OV0312;O2max was 21 ± 4 vs 27 ± 4 ml/kg/min in those whose ejection fraction increased (p < .001). Systolic blood pressure/end‐systolic volume relation was shifted upward and to the right in the former group in response to peak exercise. In contrast, the pressure‐volume relation was shifted upward and to the left in patients whose ejection fraction increased with exercise. Ejection fraction at rest did not correlate with &OV0312;O2max. There was a significant but weak correlation between peak exercise ejection fraction and &OV0312;O2max (r = .43, p < .025). Left ventricular exercise reserve, i.e., the change in ejection fraction from rest to exercise, correlated with &OV0312;O2max (r = .77, p < .0002), maximal O2pulse (r = .50, p < .005), and maximal heart rate during treadmill exercise (r = .61, p < .001). Maximal heart rate during treadmill exercise correlated with &OV0312;O2max (r = .70, p < .0002). These data suggest that impaired left ventricular function can limit &OV0312;O2max and that maximal heart rate and left ventricular exercise reserve are among the variables affecting &OV0312;O2max in patients with coronary artery disease who are not limited by angina.Circulation 70, No. 4, 552‐560, 1984.

ISSN:0009-7322    

出版商:OVID    

年代:1984

数据来源: OVID

摘要:

&NA;The detection of myocardial depression is an important goal in the management of patients with chronic severe aortic regurgitation but may be quite difficult at an early stage by the conventional basal measures of contractility. The response to afterload stress determined by angiotensin challenge and the end‐systolic pressure‐volume relationship was evaluated echocardiographically in 16 asymptomatic or mildly symptomatic patients with chronic severe aortic regurgitation, ages 15 to 56 years (mean 32 ± 12). Nine normal subjects, ages 25 to 41 years (mean 31 ± 5), served as a control group. In the group with aortic regurgitation, end‐systolic dimensions were greater than 55 mm in five of 16 patients and fractional shortening was 25% or less in two of 16. In the control group angiotensin caused a decrease of stroke volume index in six out of nine patients (15% at the most) and a mild increase in three. In the group with aortic regurgitation stroke volume index decreased by 15% or more of the basal value in nine of 16 patients and increased or decreased by less than 15% in seven of 16. Ejection fraction decreased in both groups, from 61 ± 6% to 52 ± 7% in the control group and from 56 ± 6% to 45 ± 5% in the group with aortic regurgitation. Ventricular function curves were derived by relating end‐diastolic volume index to stroke work index; seven of 16 patients had abnormal responses reflecting an afterload mismatch. End‐systolic pressure‐volume relationships were constructed; the slope of the relationship (Es) ranged from 66° to 80° (74° ± 5°) in the control group and from 46° to 72° (58° ± 7°) in the group with aortic regurgitation. In this group Es was below the 95% confidence limits of the control group in 12 of 16 patients. Considering all the tested indexes of ventricular performance, the rank order of incidence of abnormal findings in the group with aortic regurgitation was as follows: basal fractional shortening (13% of patients), basal end‐systolic dimension (31%), angiotensin‐induced decrease of stroke work index (41%) and stroke volume index (56%), and Es (75%). In conclusion, in young asymptomatic or mildly symptomatic patients with chronic severe aortic regurgitation (1) Es, derived from noninvasive measurement of systolic pressure and echocardiographic parameters, is the most sensitive index of myocardial dysfunction among those considered in this study and (2) depression of contractility is frequently present before end‐systolic dimension reaches 55 mm and fractional shortening decreases below 25%.Circulation 70, No. 4, 561‐569, 1984.

ISSN:0009-7322    

出版商:OVID    

年代:1984

数据来源: OVID

摘要:

&NA;Preoperative left ventricular systolic function is an important predictor of postoperative prognosis in patients with aortic regurgitation. Although left ventricular dysfunction is reversible after aortic valve replacement to a greater extent in patients with good preoperative exercise capacity compared with patients with impaired exercise capacity, not all patients with preserved exercise capacity demonstrate improved left ventricular function after aortic valve replacement. To determine the influence of duration of preoperative left ventricular dysfunction on postoperative reversal of left ventricular dysfunction, we studied 37 patients with aortic regurgitation who preoperatively had left ventricular dysfunction, defined as subnormal echocardiographic fractional shortening (less than 29%), and good preoperative exercise capacity, defined as completion of stage I of the NIH treadmill protocol without limiting symptoms. Eight patients were asymptomatic. In 11 patients left ventricular dysfunction was documented 18 to 57 months preoperatively (prolonged); in 10 patients left ventricular dysfunction developed in an interval of 14 months or less preoperatively (brief); in 16 patients duration of left ventricular dysfunction was unknown. Patients with brief vs those with prolonged left ventricular dysfunction did not differ with respect to severity of preoperative symptoms or exercise tolerance, echocardiographically determined left ventricular dimensions or fractional shortening (25 ± 3% [SD] vs 25 ± 3%), or radionuclide angiographic ejection fraction (42 ± 5% vs 42 ± 5%). After operation, however, patients with brief left ventricular dysfunction developed a smaller left ventricular diastolic dimension (50 ± 3 vs 59 ± 8 mm;p < .005) and a higher ejection fraction (63 ± 7% vs 43 ± 12%; p < .001) than patients with prolonged left ventricular dysfunction; postoperative ejection fraction was intermediate in patients with unknown duration of preoperative left ventricular dysfunction (48 ± 11%; p < .001). All deaths occurred in patients with either prolonged or unknown duration of left ventricular dysfunction. Thus the duration of preoperative left ventricular dysfunction in patients with aortic regurgitation is an important determinant of the reversibility of left ventricular dysfunction after aortic valve replacement.Circulation 70, No. 4, 570‐579, 1984.

ISSN:0009-7322    

出版商:OVID    

年代:1984

数据来源: OVID

摘要:

&NA;A long‐term retrospective follow‐up study was made of 120 patients (33 male, 87 female patients) with primary pulmonary hypertension — diagnosed by strict clinical and hemodynamic criteria — to obtain a better understanding of the natural history and possible pathogenetic mechanisms of the disease. The mean age at diagnosis was 34 (3 to 64) years, but only 24 patients (21%) remained alive 5 years later. Lung tissue obtained at autopsy from 56 patients revealed two major pathologic types: thromboembolic pulmonary hypertension in 32 patients (57%) and plexogenic pulmonary arteriopathy in 18 (32%). Thus, in more than half the patients undergoing autopsy the major histologic feature was thrombi without any evidence of plexiform lesions. The two groups were similar with respect to their clinical and hemodynamic features and short survival. Of the variables tested for prognostic importance by stepwise multivariate analysis, only two were significant: pulmonary arterial oxygen saturation (p < .00001) and anticoagulant therapy (p = .01). Anticoagulant therapy is recommended for patients with primary pulmonary hypertension.Circulation 70, No. 4, 580‐587, 1984.

ISSN:0009-7322    

出版商:OVID    

年代:1984

数据来源: OVID

摘要:

&NA;We sought to determine whether an association existed between the echocardiographic appearance of left ventricular thrombi and systemic embolization. We reviewed the clinical and echocardiographic characteristics of 60 patients who underwent diagnostic two‐dimensional echocardiography for left ventricular thrombi. Sixteen of these 60 patients (27%) had evidence of systemic embolization. Multiple echocardiographic characteristics of left ventricular thrombi were analyzed, including mobility, shape, heterogeneity, echo density, layering, central echo lucency, presence within an aneurysm, and association with low‐density swirling echoes. Incidence of embolization was significantly higher in patients with thrombi that were mobile or protruded into the left ventricular cavity (p < .002 and p < .05, respectively). Bayesian analysis indicated that the pretest likelihood for embolization was 27% and increased in the presence of mobility, central echo lucency, and protrusion to 60%, 50%, and 40%, respectively. A stepwise regression indicated that mobility was the first and protrusion the second most helpful echocardiographic characteristic in identifying patients with embolic phenomena. Clinical features were of less help in identifying the risk for embolization of patients with left ventricular thrombi. Nine of 31 patients (29%) with recent myocardial infarction (less than 3 weeks) had emboli in contrast to five of 26 patients (19%) with remote myocardial infarction (greater than 3 weeks) (p = NS). The three patients without infarction had congestive cardiomyopathy and two had emboli.Circulation 70, No. 4, 588‐598, 1984.

ISSN:0009-7322    

出版商:OVID    

年代:1984

数据来源: OVID