摘要:

A progression of univariate followed by multivariate analyses was applied to 46 variables selected from the clinical examination, exercise test, coronary arteriography, and quantitative angiographic assessment of left ventricular function in patients with coronary disease to determine those variables most predictive of survival. For the 733 medically treated patients, the final Cox's regression analysis showed that the left ventricular ejection fraction was most predictive of survival, followed by age, number of vessels with stenosis(es) .70%, and ventricular arrhythmia on the resting electrocardiogram. For the 1870 surgically treated patients, ventricular arrhythmia on the resting electrocardiogram was most predictive of survival followed by ejection fraction, heart murmur, left main coronary artery stenosis .50%, and use of diuretic agents.

ISSN:0009-7322    

出版商:OVID    

年代:1979

数据来源: OVID

摘要:

Within the larger Seattle Heart Watch arteriography registry, surgically treated patients nonrandomly selected for direct myocardial revascularization were matched to medically treated patients such that each of the 287 pairs was identical in seven variables (ejection fraction, ventricular arrhythmia on resting electrocardiogram, age, heart murmur, stenosis of left main coronary artery > 50%, number of vessels with tenosis > 70%, and use of diuretics) previously demonstrated to be independently predictive of survival. Actuarial survival analyses based on cardiovascular deaths (average follow-up 3.5 years) indicate improved survival for the entire surgical matched pair cohort (p = 0.008) and for the surgically treated subgroup with twovessel disease (p = 0.0002) when compared to the medical cohort. These results were confirmed by examination of the entire arteriography registry (n = 1524) in which these seven variables were known, using Cox's model for survival analysis. This multivariate, statistical technique indicated that the surgical mode of therapy was significantly predictive of improved survival in surgically treated patients for the entire registry (p = 0.008) and for the subgroup with two-vessel disease (p = 0.0005).

ISSN:0009-7322    

出版商:OVID    

年代:1979

数据来源: OVID

摘要:

SUMMARY The accuracy in determining the pressure gradient in the Bjork-Shiley mitral implant from noninvasive ultrasound Doppler data was explored in nine adult patients. Manometric and ultrasound data were collected simultaneously, and identical diastolic periods were used to compare the manometric gradient (APM) with the gradient obtained from ultrasound data (APu). In the nine patients the mean diastolic value of APM ranged from 2-12.5 mm Hg and the difference between the mean diastolic values of APM and APu was 0.3 ± 1.0 mm Hg (SD). The results of the investigation indicated that the method is accurate and reliable in the noninvasive determination of the mean diastolic gradient in the Bjork-Shiley mitral implant.

ISSN:0009-7322    

出版商:OVID    

年代:1979

数据来源: OVID

摘要:

SUMMARY We examined the long-term effects of closed instrumental mitral commissurotomy on mitral valve area (MVA) in 18 patients, followed for as long as 14 years after successful operation. Each patient had preoperative and early postoperative cardiac catheterization; a late postoperative determination ofMVA was obtained 10-14 years (mean 12.2 years) after commissurotomy. In 17 patients, the MVA was determined by cross-sectional echocardiography and in one patient by repeat cardiac catheterization. Thirteen of 18 patients had no change in MVA between early postoperative study (mean MVA = 2.7 cm2) and late postoperative study (mean MVA = 2.9 cm2). MVA in five patients decreased 0.7-2.2 cm2 (mean 1.4 cm2) during the followup period. In these five patients, the mean MVA at early postoperative study was 2.7 cm2 and at late postoperative study was 1.3 cm2 (p < 0.001). At late postoperative evaluation, cardiac symptoms were associated with severity of mitral stenosis but did not predict restenosis. A successful, closed, instrumental mitral commissurotomy can provide substantial long-term improvement in MVA.

ISSN:0009-7322    

出版商:OVID    

年代:1979

数据来源: OVID

摘要:

Arrhythmias which last for only a few cycles or exhibit activation sequences that change from cycle to cycle may occur during the intraoperative study of ventricular tachyarrhythmias. To map these transient, varying arrhythmias requires recording from numerous sites simultaneously, which cannot be done with a single, hand-held electrode probe. Therefore, a computerized method was developed to record potentials simultaneously from up to 27 electrodes and to display epicardial and transmural activation sequences rapidly.Three arrays of electrodes are used. The electrodes of the first array are distributed over the epicardium of both ventricles and fixed within a flexible nylon mesh sock. The electrodes of the second array form a 3-cmsquare grid and are used to obtain a more detailed activation map of a small region of epicardium. The electrodes of the third array are spaced along the shafts of needles that are inserted through the myocardium to record transmural activation. The potentials recorded from an array of electrodes and the computer-selected activation times at the electrodes are displayed for visual inspection after which a map of activation is drawn. The activation sequence of a single cycle can be displayed 10 minutes after recording the potentials. The activation map obtained from the sock array determines the placement of the grid array; the map resulting from the grid array determines the placement of the needle array. Thus, the region responsible for initiating an arrhythmia can be determined if the arrhythmia can be induced three or more times.

ISSN:0009-7322    

出版商:OVID    

年代:1979

数据来源: OVID

摘要:

Two or more morphologically distinct ventricular tachycardias were observed during electrophysiologic study in 14 patients with chronic sustained ventricular tachycardia. Nine of these patients hadclinical ventricular tachycardia with multiple morphologies. During the study 13 patients manifested both right bundle branch block (RBBB) and left bundle branch block (LBBB) morphologies. The remaining patient had RBBB with both right and left axis deviation. Changing morphologies were observed spontaneously in four patients and could be produced in all 14 by ventricular stimulation. In 12 patients both RBBB and LBBB originated in the left ventricle, and in 11 of these patients, from within a left ventricular aneurysm. Diastolic fragmented activity representing reentry was unchanged during both morphologies in four patients and during one morphology in five patients. Epicardial mapping confirmed the aneurysm as the site of origin of multiform ventricular tachycardias in two patients. Our data suggest that 1) ventricular tachycardia is frequently pleomorphic; 2) multiple morphologies usually represent variable exit sites and/or ventricular activation during the same tachycardia; and 3) there is a frequent association of pleomorphic ventricular tachycardia with left ventricular aneurysm.

ISSN:0009-7322    

出版商:OVID    

年代:1979

数据来源: OVID

摘要:

A stable junctional rhythm was produced in 16 dogs after surgical excision of the sinoatrial node and a large section of the crista terminalis. An unstable ectopic atrial rhythm appeared within the first week after surgery in 94% of the dogs. The pacemaker instability was characterized by spontaneous pacemaker shifts and periodic episodes of asystole which were prominent for several months after surgery in most of the dogs. In contrast to sinus arrhythmia observed before surgery, the ectopic atrial arrhythmias were not related to the respiratory cycle. The prompt disappearance of the asystoles after atropine or during treadmill exercise indicated the essential role of the vagus in producing the unstable rhythms. Atropine increased the average rate of the ectopic rhythms from 63 ± 3 beats/min to 107 ± 9 beats/min (p < 0.001) and shortened the corrected recovery time (CRT) following overdrive pacing from 3.8 ± 0.3 seconds to 1.9 ± 0.6 seconds (p < 0.001). Propranolol, in the absence of atropine, decreased the spontaneous heart rate from 56 ± 5 beats/min to 39 ± 6 beats/min (p < 0.01), and increased the CRT to 6.5 ± 2 seconds (p < 0.001) when administered after atropine. The data suggest that unstable ectopic atrial pacemakers could be responsible for ome of the arrhythmias associated with the sick sinus syndrome in man.

ISSN:0009-7322    

出版商:OVID    

年代:1979

数据来源: OVID

摘要:

Transmitral blood flow was measured in man by numerical differentiation of left ventricular volume as a function of time in 11 patients undergoing cardiac catheterization. Using this technique, transmitral blood flow may be studied in a variety of pathologic states without the need for surgically introduced flowmeters. Just before left ventriculography, echocardiography of the mitral valve was performed. The pattern of transmitral blood flow was strikingly similar to the diastolic movement of the anterior mitral leaflet. At any equivalent diastolic filling time, the percent of the integrated area beneath the curve inscribed by the diastolic anterior mitral leaflet echoes closely approximated the percent of stroke volume which had entered the left ventricle. This observation supports the hypothesis that mitral leaflet motion accurately reflects transmitral flow. Consequently, at a given time during diastole, the relative velocity of transmitral flow and the percent of the stroke volume which has entered the left ventricle may be approximated noninvasively from the anterior mitral leaflet echogram.

ISSN:0009-7322    

出版商:OVID    

年代:1979

数据来源: OVID

摘要:

Because abnormalities of the immune system may be involved in the pathogenesis of idiopathic congestive cardiomyopathy (ICCM), we studied suppressor cell function in patients with ICCM. Previously described in vitro techniques were modified for optimal demonstration of concanavalin A (con A)-inducible suppressor activity by peripheral blood mononuclear cells (PBM). Baseline responses in the mixed leukocyte reaction (MLR) were similar for PBM from 16 normal subjects, eight patients with end-stage coronary artery disease (CAD), and 18 patients with ICCM. In the presence of autologous, con A-treated PBM, MLR responses were significantly suppressed for normals (geometric mean disintegrations/min decreasing from 36,308 to 4677; p < 0.001) and for CAD patients (25,703 decreasing to 50l1;p < 0.001). In contrast, autologous, conc A-treated PBM from patients with ICCM failed to suppress MLR responses (30,902 increasing to 44,688; p < 0.005). Similar results were observed in mitogen stimulation experiments. Con A-treated PBM from a normal subject suppressed the MLR response of PBM from an ICCM patient. The failure of con A-treated PBM to inhibit in vitro immune responses may reflect an in vivo defect in suppressor cell function in patients with ICCM.

ISSN:0009-7322    

出版商:OVID    

年代:1979

数据来源: OVID

摘要:

Eleven patients with hypertrophic obstructive cardiomyopathy and eight patients with idiopathic congestive cardiomyopathy underwent extensive neuromuscular studies to determine if a skeletal myopathy is associated with uncomplicated primary cardiomyopathy. The clinical examination revealed peripheral neuropathies in six patients, but no evidence of muscle weakness or atrophy. Nerve conduction studies demonstrated a neuropathy in five of these six and in one other patient: three were in the hypertrophic group and three in the congestive group. Seven patients had abnormal electromyography, but none had characteristic myopathic changes. Of these seven patients, muscle biopsies showed denervation in two patients in the congestive group and type II atrophy in two patients in the hypertrophic group. We found no evidence ofprimary skeletal muscle involvement; however, neuropathic features and biopsy changes of denervation were present in both groups.

ISSN:0009-7322    

出版商:OVID    

年代:1979

数据来源: OVID