ISSN:0009-7322    

出版商:OVID    

年代:1976

数据来源: OVID

ISSN:0009-7322    

出版商:OVID    

年代:1976

数据来源: OVID

ISSN:0009-7322    

出版商:OVID    

年代:1976

数据来源: OVID

摘要:

SUMMARY A comparison of electrocardiographic manifestations of left atrial enlargement (LAE) and left atrial size by echocardiography was made in 307 patients in sinus rhythm. Electrocardiographic criteria used were L: P wave duration in lead II equal to or greater than 0.12 sec; Va: the ratio of the duration of negative terminal P in V1to the P-R segment equal to or greater than 1.0; Vb: a negative P terminal force in V, less than −0.03 mm sec. The echocardiographic diagnosis of left atrial enlargement was based on 1) transverse dimension greater than 4.0 cm, or 2) a ratio of transverse atrial to transverse aortic root dimension greater than 1.17. In the presence of left atrial enlargement, a combination of criteria occurred more often than a single criterion. The overall predictive index of the electrocardiogram for left atrial enlargement was 63% (excluding criterion Vbraised probability to 80%); and that for absence of left atrial enlargement was 78%. The index of coarse versus fine fibrillary waves was unreliable in predicting left atrial enlargement. Changes in P wave morphology may be used as a reasonably specific but less sensitive indicator of left atrial enlargement.

ISSN:0009-7322    

出版商:OVID    

年代:1976

数据来源: OVID

摘要:

SUMMARY A contrast echocardiographic technique using peripheral vein injections for the detection and localization of intracardiac right-to-left shunting is described. Fifty children underwent cardiac catheterization and peripheral contrast echocardiographic studies. The site, degree, and direction of shunting were established at catheterization by oximetry, indicator dilution analysis and/or angiography. Peripheral vein injections were performed from the right antecubital vein or the right saphenous vein. Right-to-left shunts were documented at catheterization in 27/50 patients; contrast echocardiographic studies indicated the presence and level of shunting in all 27 patients. The contrast echocardiographic technique using peripheral vein injections detects and localizes right-to-left intracardiac shunting. It is a safe and sensitive method to evaluate systemic desaturation in ambulatory and postoperative patients.

ISSN:0009-7322    

出版商:OVID    

年代:1976

数据来源: OVID

摘要:

SUMMARY The echocardiographic features of congenital left ventricular inflow obstruction are described in six patients. The echocardiograms in two patients with cor triatriatum were distinguished by normal mitral valve motion and an abnormal echo within the left atrium. In two patients with supravalvar mitral ring, in addition to abnormal mitral valve motion, an abnormal echo, presumably originating from the obstructive membrane, was located between the anterior and posterior mitral leaflets. In two cases of parachute mitral valve, mitral valve motion was abnormal. In one of these cases there were multiple mitral valve echoes similar to those found in supravalvar mitral ring.The echocardiographic identification of an obstructive membrane within the left atrium is difficult because of the occurrence of artifacts. However, membranes may be identified if careful scanning techniques are employed in patients in whom left ventricular inflow obstruction is suspected. The echocardiogram is useful in detecting mitral valve abnormalities in these patients and is valuable in cases where mitral valve replacement is contemplated.

ISSN:0009-7322    

出版商:OVID    

年代:1976

数据来源: OVID

摘要:

SUMMARY Echocardiograms of 52 patients with the Wolff-Parkinson- White (WPW) syndrome were investigated. Abnormal patterns of motion were observed in the left ventricular posterior wall (LVPW) and the interventricular septum (IVS). The abnormal LVPW motion was presumably specific for the syndrome and included early onset of the anterior motion which preceded the first heart sound (S1) and a premature peak formation of the anterior displacement which occurred before the second heart sound. The latter was usually followed by a second lower peak. These findings seem to suggest that both contraction and relaxation of LVPW begin earlier than normal due to ventricular pre-excitation initiated at or near the LVPW. The IVS abnormality characteristic of the syndrome was a posterior protrusion, the onset of which preceded S1. Subsequent motion of IVS was either paradoxical or hypokinetic during ejection. These IVS abnormalities were quite similar to those observed in left bundle branch block. The abnormal LVPW motion was observed in all 20 Type A patients and 10 of the 32 Type B patients. The abnormal IVS motion was observed in 10 Type B patients. We feel that echocardiography could be used as an auxiliary noninvasive means of locating the pre-excitation site in patients with WPW.

ISSN:0009-7322    

出版商:OVID    

年代:1976

数据来源: OVID

摘要:

SUMMARY We have studied 135 patients with the pre-excitation syndrome and have demonstrated evidence of multiple accessory pathways in 20 patients. Five patients had two distinct accessory atrioventricular (A-V) connections, associated with enhanced A-V node conduction in one patient. Twelve patients had a single accessory A-V connection associated with enhanced A-V conduction. In one of these there was an additional fasciculo-ventricular connection. One patient had an accessory A-V connection associated with a nodoventricular bundle. Two patients had fasciculo-ventricular connections combined with enhanced A-V conduction. The latter two patients had electrocardiograms suggestive of a complete accessory A-V connection. Patients with enhanced A-V conduction had shorter cycle lengths during reciprocating tachycardia, primarily because of a short A-H during the dysrhythmia, than those without such conduction. In addition, patients with enhanced A-V conduction demonstrated more rapid conduction from atrium to His bundle during induced atrial fibrillation and two developed life-threatening ventricular responses during atrial fibrillation. A nodo-ventricular pathway was documented to participate in reciprocating tachycardia in one patient. Surgery was undertaken in 13 patients. In 11, the intraoperative mapping studies confirmed the preoperative predictions. In two patients, the presence of a second accessory A-V connection was documented after ablation of one.

ISSN:0009-7322    

出版商:OVID    

年代:1976

数据来源: OVID

摘要:

SUMMARY The goal of this study was to determine if changes in the epicardial QRS complex after coronary artery occlusion (CAO) can be used to evaluate the efficacy of interventions designed to limit infarct size. Forty-one open-chest dogs with CAO were studied: 15 were controls, 18 received hyaluronidase and eight received propranolol starting 20 minutes after CAO. Epicardial ECGs were recorded at specific time intervals to analyze ST-segment elevation and changes in Q and R waves. Transmural specimens were obtained 24 hours after CAO from the same sites at which ECGs were recorded. Q wave development (ΔQ), R wave fall (ΔR), and their combination (ΔR + ΔQ) at 24 hours correlated with the extent of necrosis, as de- termined by myocardial creatine phosphokinase activity depression and histologic appearance. In the control group ST-segment elevation 15 minutes after CAO (ST18m) predicted changes in Q and R waves 24 hours later; in the treated groups, the same STism prior to drug administration resulted in significantly less QRS changes. Thus, I) Q wave development and R wave fall 24 hours after CAO accurately reflect myocardial necrosis. 2) ST18mpredicts subsequent changes in Q and R waves. 3) The efficacy of hyaluronidase and propranolol, agents previously shown to reduce myocardial necrosis, can be detected by less Q wave development and a smaller fall in R wave voltage.

ISSN:0009-7322    

出版商:OVID    

年代:1976

数据来源: OVID

摘要:

SUMMARY Conduction of the sino-atrial impulse from the high right atrium to the ventricles was studied by intracardiac electrography in 21 unoperated patients, age 3 months to 11 years, with endocardial cushion defects (ECD). The high right atrium-to-low right atrium conduction time was prolonged in 15 of 18 subjects (mean 57 ± 20 msec). The low right atrium-to-His bundle conduction time (LRA-H) was normal in 16 of 17 subjects (mean 82 ± 30 msec), prolonged in one. The His-to-ventricle conduction time (H-V) was normal in 16 of 17 subjects (mean 37 ± 8 msec), equivocally short in one.Nine patients with ECD, age 3 to 21 years, were studied postoperatively. One had an acquired complete atrioventricular block in the His bundle. Two had prolonged LRA-H and two prolonged H-V. The surface ECG failed to identify accurately either prolonged atrioventricular conduction or the site of prolongation.

ISSN:0009-7322    

出版商:OVID    

年代:1976

数据来源: OVID