ISSN:0009-7322    

出版商:OVID    

年代:1976

数据来源: OVID

摘要:

The effects of left axis shift (> −30°) on intraventricular conduction time (IVCT) were studied in 63 subjects in whom electrocardiograms before and after appearance of the left axis shift were available. Subjects with electrocardiographic evidence of left or right ventricular hypertrophy, left or right bundle branch block, myocardial infarction, pre-excitation and those receiving antiarrthythmic drugs were excluded.The IVCT increased by an average of 25 msec when the QRS axis shifted to −30° or beyond. When the individual AQRS was related to the IVCT a linear correlation (r= −0.8) was observed. It appears that a continuum relation between the AQRS and the IVCT exists throughout the counterclockwise range of +90° to −90°. In all leftward shifts in AQRS from +90° there is a prolongation in IVCT.Our observations indicate that all leftward shifts in AQRS, including the extreme left axis shift (left anterior hemiblock), represent a spectrum of intraventricular conduction block.

ISSN:0009-7322    

出版商:OVID    

年代:1976

数据来源: OVID

摘要:

Sino-atrial conduction time (SACT) may be calculated from the difference between the length of the return cycle and the spontaneous cycle, using programmed premature atrial stimulation during spontaneous sinus rhythm. This approach to sinoatrial conduction assumes that sinus node automaticity is not changed by premature depolarization. In order to validate this assumption, we compared the length of the post-return cycles to the spontaneous cycle length in 71 patients. Patients were grouped according to clinical diagnosis and the value of calculated SACT.At long coupling intervals at which no reset of the sinus node occurred there was only a small prolongation of the post-return cycles (less than 8A msec, on an average) compared to the spontaneous cycle length. This suggests no or only an insignificant effect of premature depolarization on the sinus node. However, during test stimuli leading to reset of the sinus node, the post-return cycles were signficantly prolonged between 20 to 30 msec, on an average. The response of the individual cases sometmes varied to a great extent. In patients who demonstrated a progressive linear prolongation of the return cycles at decremental shortening of the test interval, there was no significant prolongation of the post-return cycles versus the spontaneous cycle length.We conclude that 1) premature depolarization of the sinus node may have a depressant effect on sinus node automaticity, which, if present, is usually small; 2) calculation of SACT using the extrastimuus technique may overestimate true SACI.

ISSN:0009-7322    

出版商:OVID    

年代:1976

数据来源: OVID

摘要:

Frank vectorcardiograms (VCG) and clinical records of 243 patients with right bundle branch block (RBBB) were compared. The patients were classified into three categories on the basis of VCG criteria. The first category included 100 patients with a normal frontal axis, and the second category included 44 patients with concomitant left anterior hemiblock. The third category consisted of 99 patients with RBBB and myocardial infarction. The VCGs were classified into three types according to the QRS configuration in the transverse plane. In type I the initial forces were anterior and counterclockwise and the afferent limb crossed the midline posterior to E point; in type II the initial forces were anterior and counterclockwise and the afferent limb crossed the midline anterior to or through E point; and in type III the entire transverse loop was clockwise and anterior to E point. The patients were further classified according to the presence or absence of cardiac failure or severe pulmonary disease.In patients with RBBB and a normal axis, cardiac failure or severe pulmonary disease was found in five of 49 patients with type I, 17 of 31 with type II, and 18 of 20 with type III pattern. In patients with RBBB and left anterior hemiblock, significant disease was found in one of 17 with type I, five of 16 with type II, and eight of 11 with type III pattern. These data show that, in patients with RBBB, the position of the afferent limb in the transverse plane can be used to predict cardiac failure or severe pulmonary disease.

ISSN:0009-7322    

出版商:OVID    

年代:1976

数据来源: OVID

摘要:

We have studied the disposition of the cardiac conducting tissues in four hearts from situs solitus individuals possessing primitive ventricles without outlet chambers. These hearts correspond to the type of univentricular heart defined as common ventricle by Lev. All the hearts studied possessed normally positioned great arteries. Two groups, each consisting of two hearts, could be distinguished.The first type possessed a small posterior ridge which divided the posterior portion of the primitive ventricle into right and left ventricular sinuses. The papillary muscles to the atrioventricular valves were separate structures and arose on each side of this posterior ridge. The conducting tissues in these hearts arose from an atrioventricular node situated in the atrial septum but deviated posteriorly.The atrioventricular bundle pierced the fibrous annulus posteriorly and descended on the posterior ridge, lying to its left side. A bifurcation was not identified, and bundle branches were not present. The other two hearts had no posterior ridge. A common posterior papillary muscle supported both atrioventricular valves, and in one a marked anterior muscle bar produced obstruction of the pulmonary outflow tract. The connecting atrioventricular node was situated laterally in the right atrioventricular valve orifice, and the atrioventricular bundle descended into the right parietal wall of the primitive ventricle. A bifurcation and bundle branches were not observed.The disposition of conducting tissue in these hearts differs from that found in "primitive ventricle with outlet chamber" in that the connecting atrioventricular node and bundle are situated anteriorly and are intimately related to the transposed pulmonary artery outflow tract in the latter anomaly. The surgical significance of these findings is emphasized.

ISSN:0009-7322    

出版商:OVID    

年代:1976

数据来源: OVID

摘要:

Two hundred and twenty patients were selected for testing with the patient-activated Pocket Electrocardiograph (PECG) because angina pectoris and similar diagnoses could not be excluded. They were selected during a 30-month period from the population of approximately 12,000 new patients visiting a general medical clinic at Nippon Medical School Hospital. The test confirmed the preliminary diagnosis in 79.1%; 9.6% were not confirmed and 11.3% did not have an attack during the PECG examination. The PECG examination is useful in the differential diagnosis of angina pectoris, cardiac neurosis, phantom arrhythmia, and arrhythmia when the routine ECG examinations are essentially negative.

ISSN:0009-7322    

出版商:OVID    

年代:1976

数据来源: OVID

摘要:

Twenty-six patients with Wolff-Parkinson-White (WPW) syndrome were studied by echocardiography. They were classified into the following WPW types: anterior right ventricular pre-excitation (Type I)-six patients; posterior right ventricular pre-excitation (Type II)-six patients; posterior left ventricular preexcitation (Type III) – fourteen patients. Twenty-three patients were in WPW at the time of study. Four patients with Type I WPW had abnormal systolic motion of the interventricular septum: three paradoxical and one flat. Patients with Type II and Type III WPW had no septal motion abnormalities related to pre-excitation. Three patients had intermittent WPW, Type III; in all three only minor changes in normal septal motion were apparent on WPW beats. Associated cardiac abnormalities were evident in six patients: two mitral prolapse (one Type II WPW and one Type III); one idiopathic hypertrophic subaortic stenosis (Type III); one congestive cardiomyopathy (Type III); one hypertrophic nonobstructive cardiomyopathy (Type I); and one atrial septal defect (Type II). We conclude that abnormal interventricular septal motion may occur with Type I WPW abnormality. Other abnormalities are detectable by echocardiography in a high proportion of WPW patients, but do not appear to be associated with any single Wolff-Parkinson-White type.

ISSN:0009-7322    

出版商:OVID    

年代:1976

数据来源: OVID

摘要:

Aortic root motion was studied in 24 normal volunteers at rest and during the Valsalva maneuver, isometric exercise, and amyl nitrite inhalation. In addition root motion was correlated with the stroke volumes determined at cardiac catheterization in 24 patients. The root has distinct systolic movement, the amplitude and duration of which were easily measured both at rest and during the interventions.At rest, the mean (±1 SE) systolic amplitude of the anterior aortic wall was 11.2 + 0.5 mm and that of the posterior wall 9.5 ± 0.3 mm. During the strain phase of the Valsalva maneuver anterior wall amplitude fell to 8.2 ± 0.4 mm and the posterior wall to 7.3 ± 0.5 mm (P ⩽ 0.001). With release, anterior wall amplitude rebounded to 12.5 ± 0.8 mm and the posterior wall to 10.8 ± 0.5 mm, values greater than control (P ⩽ 0.01). With isometric exercise there was no change in amplitude compared to rest; however, amyl nitrite caused an increase in the anterior wall to 13.5 ± 0.8 mm and posterior wall to 11.9 ± 0.6 mm (P ⩽ 0.01). In the patient group the amplitude of posterior wall motion correlated weakly with cardiac index (r= 0.63) and stronger with stroke index (r= 0.78).This study quantifies the echocardiographic pattern of normal aortic root motion. The findings indicate that the aortic root motion is an index of stroke volume; they further suggest that root motion is acutely sensitive to variations in stroke volume since its amplitude changed in accord with the documented effects of the employed maneuvers on stroke volume.

ISSN:0009-7322    

出版商:OVID    

年代:1976

数据来源: OVID

摘要:

Echocardiograms were performed in thirty-six patients (aged 4 to 36 years) with proven coarctation of the aorta. Nineteen patients (53%) were found to have marked diastolic eccentricities of their aortic valves (Eccentricity Index > 1.5), indicating the presence of bicuspid aortic valves. One of these patients also had multilayered aortic root echoes in diastole. Five patients had angiographic proof of their aortic valve morphologies which corroborated the echo findings. Five patients with bicuspid aortic valves showed mitral valve diastolic flutter indicative of aortic regurgitation. Idiopathic hypertrophic subaortic stenosis (IHSS) was suspected in four patients (11%) with abnormal systolic anterior motion of the mitral valve; three of these patients also had asymmetric septal hypertrophy. There was catheterization proof of IHSS in one patient. Two patients (5.6%) demonstrated mitral valve prolapse.

ISSN:0009-7322    

出版商:OVID    

年代:1976

数据来源: OVID

摘要:

Quantitative Doppler ultrasonographic flow velocity determinations are reported from 39 normal control subjects and 80 patients with angiographically documented peripheral arterial disease, in whom femoral, posterior tibial and dorsalis pedis arteries were studied. The mean control values of the most useful parameters were: femoral artery: peak forward velocity (PFV) cm/sec: 40.7 ± 10.9, deceleration (Dec.) cm/sec 2: 250.9 ± 60.0, peak/mean velocity (P/MV): 4.8 ± 1.6; posterior tibial artery: PFV: 16.0 ± 10.0, Dec.: 129.8 + 75.7, P/MV: 4.8 ± 2.5; dorsalis pedis artery: PFV: 168 ± 5.7, Dec.: 137.9 ± 54.5, P/MV: 6.0 ± 4.1. The values of these measurements in the patients with arterial occlusive disease were all significantly lower, and also permitted distinguishing those with multilevel disease from those with a single site of occlusion. Quantitative evaluation of the Doppler ultrasonogram permits obtaining detailed functional information on the degree of arterial flow impairment in patients with peripheral arterial occlusive disease.

ISSN:0009-7322    

出版商:OVID    

年代:1976

数据来源: OVID