Mary Jo Black

Detection of Left Ventricular Asynergy by Echocardiography

The purpose of this study was to determnie if echocardiography could detect left ventricular asynergy. Forty-eight patients underwent selective coronary arteriography and cineventriculography for the evaluation of chest pain. Four patients were studied twice: three before and after myocardial revascularization and one before and after an intervening myocardial infarction. Echocardiographic M-mode scans were registered on a strip chart as the left ventricle was scanned with an ultrasonic beam from the aortic root to the region of the posterior papillary muscle approximately 18 hrs prior to the catheterization studies.Ten of the forty-eight patients had no evidence of coronary artery disease. All ten patients had normal ventriculograms in right anterior oblique projection and their echocardiographic scans showed all areas of the left ventricular posterior wall endocardium to move anteriorly 0.9-1.4 cm (mean 1.2 cm) and all parts of the left side of the interventricular septum to move posteriorly 0.3-0.8 cm (mean 0.5 cm) during systole. The 38 patients with significant obstructive coronary artery disease had a total of 42 studies; 25 of these studies showed left ventricular asynergy on the ventriculogram taken in right anterior oblique. The echocardiograms associated with all but one of these studies demonstrating left ventricular asynergy had abnormal motion of some part of the interventricular septum and/or left ventricular posterior wall. Seventeen studies in patients with significant coronary artery disease did not exhibit left ventricular asynergy on the ventriculogram but eight of these studies were associated with distinctly abnormal echocardiograms.None of the ten patients with significant coronary artery disease and normal echocardiograms had evidence of transmural infarction on their electrocardiograms. Echocardiographic abnormalities correlated with the anatomic area predicted by the myocardial infarction pattern on the electrocardiogram in 18 of 20 patients.All patients demonstrating abnormal echographic interventricular septal motion had a significant obstructive lesion in the left anterior descending coronary artery. In the absence of significant involvement of the left anterior descending coronary artery, echographically recorded interventricular septal motion was invariably normal. On the other hand, eight patients had significant obstruction in their left anterior descending coronary artery and their echographic interventricular septal motion was normal.The results of this correlative study indicate that M-mode echocardiographic scans can detect left ventricular asynergy and may possibly predict regional myocardial involvement in coronary artery disease.

Echocardiographic Features of Congestive Cardiomyopathy Compared with Normal Subjects and Patients with Coronary Artery Disease

Echocardiograms of ten patients with congestive cardiomyopathy were compared to those of three groups of patients: (1) 17 with no catheterization or angiographic evidence of cardiac disease; (2) 19 with 75% or greater obstruction of one or more coronary arteries (CAD); and (3) 8 with previous myocardial infarction and congestive heart failure (CAD-CHF). Echocardiographic values of interest included the left ventricular internal dimension at end-diastole/body surface area (LVIDd index), the amplitudes of the left septal echo (LSa) and posterior endocardial echo (ENa), LSa + ENa, and the maximum rate of rise of the posterior endocardial echo ([See Equation in PDF File]). Septal and posterior wall thicknesses were measured and the presence or absence of pericardial effusion and abnormal mitral valve closure were observed. All of the left ventricular measurements were significantly different when comparing the cardiomyopathy group with the normal and CAD groups. Differentiating cardiomyopathy from the CAD-CHF group was far more difficult with the only highly significant difference being the LSa + ENa (P < 0.001). Only one cardiomyopathy patient and one CAD-CHF patient had a sum of LSa + ENa overlapping the other group.These results are consistent with the diffuse disease usually seen in congestive cardiomyopathy and the segmental nature of coronary artery disease in which some area of the left ventricle moves well even in the presence of congestive heart failure.

Systolic thickening and thinning of the septum and posterior wall in patients with coronary artery disease, congestive cardiomyopathy, and atrial septal defect.

SUMMARYEchocardiographic septal and posterior wall thicknesses and the percent change with systole were measured in 146 patients with the following diagnoses: acute myocardial infarction (40), chronic coronary artery disease (49), congestive cardiomyopathy (8), atrial septal defect (20), and no cardiac disease (29). Mean diastolic thicknesses for the groups of patients with coronary artery disease and congestive cardiomyopathy were not significantly different from normal although there were abnormal values for individual patients within each group. Mean diastolic thickness of the septum was greater than normal for the group with atrial septal defect (P < 0.02). Wall thinning with systole was associated with acute infarction or ischemia (P < 0.0001); decreased thickening (less than normal) commonly occurred in patients acute myocardial infarction, chronic coronary artery disease, congestive cardiomyopathy. Patients with atrial septal defect normal thickening with abnormal motion.Results of this study show that 1) systolic thinning is indicative an acute event; 2) abnormal changes in systolic wall thickening occur commonly in patients with coronary artery disease or congestive cardiomyopathy; and 3) abnormal wall motion may occur without abnormal wall thickening, as the echoes of patients with atrial septal defect indicate.

Role of echocardiography in patients with coronary artery disease

Impaired left ventricular performance, one of the hallmarks of coronary artery disease, can be detected by echocardiography in various ways. One of these approaches is the recording of abnormal wall motion. Because of the way in which the left ventricle can be examined echocardiographically, this technique has the capability of detecting regional wall abnormalities. In fact echocardiography is probably the most sensitive technique available, including even contrast ventriculography, for the detection of akinetic, hypokinetic or dyskinetic wall segments. With increasing experience it is apparent that more areas of the left ventricle can be examined echocardiographically than had previously been thought possible. Newer techniques include directing the ultrasonic beam not only through the body of the left ventricle but also toward the apical portion of the ventricle near the vicinity of the papillary muscles. In addition the true anterior left ventricular wall can be examined by moving the transducer laterally away from the left sternal border. Yet another approach utilizes a subxiphoid position for the transducer while the ultrasonic beam is directed through the medial portion of the septum and posterolateral wall of the left ventricle. M-mode scanning techniques together with recently developed cross-sectional echocardiographic instruments give great promise of improved detection of abnormalities of ventricular shape, especially the presence of aneurysms. The cross-sectional approach makes it possible to examine the left ventricular apex, an area virtually impossible to record with M-mode echocardiography. Recording of left ventricular dimensions and abnormal mitral valve motion may help in assessing overall left ventricular performance. A dilated left ventricular dimension in the vicinity of the mitral valve seems to be an ominous finding both in patients with acute myocardial infarction and in patients with chronic coronary disease being considered for possible surgery. Another echocardiographic sign of abnormal ventricular performance is altered closure of the mitral valve, which reflects a significantly elevated left ventricular diastolic pressure. These echocardiographic techniques are still in the investigational stages and are more technically difficult than the usual echocardiographic applications. However, the preliminary data are encouraging and make us hopeful that echocardiography will prove to be an important tool in the overall evaluation of the left ventricle in patients with coronary artery disease.

Anterior left ventricular wall echoes in coronary artery disease. Linear scanning with a single element transducer.

Abstract The feasibility and usefulness of obtaining anterior left ventricular wall echoes were studied using a linear cardiac scan with a single element tranducer and M mode recordings. One hundred four patients were examined: 50 with acute myocardial infarction and 54 who underwent left ventricular angiography and coronary cineangiography for evaluation of chest pain. Of the 54 patients with cardiac catheterization studies, 11 had no evidence of cardiac disease, 42 had 50 percent or greater obstruction in one or more of the three major coronary arteries and one had aortic insufficiency. Anterior left ventricular wall echo motion toward the transducer or absence of motion during ejection was called abnormal, and motion away from the transducer during ejection was interpreted as normal. Abnormal motion was seen in four of four patients with an isolated lesion of the anterior descending coronary artery, in one of three with an isolated lesion of the right coronary artery and in neither of two with an isolated lesion of the left circumflex artery. Of the 20 patients with obstructive coronary artery disease by arteriography and abnormal left ventricular wall echo motion, 18 had obstruction of the left anterior descending artery with or without other disease. Correlation of the anterior left ventricular echograms with the left ventricular angiograms was poor, with agreement in only 66 percent (33 of 50) of cases. Twenty-five of 26 patients with acute infarction and abnormal anterior left ventricular wall echo motion had electrocardiographic changes indicative of anterior or lateral wall infarction, or both. Twenty-five of 34 patients with electrocardiographic changes indicative of anterior wall infarction had an abnormal anterior wall motion echo. This study shows that obtaining the anterior left ventricular wall echo is feasible and useful in patients with coronary artery disease since abnormal anterior left ventricular wall motion is closely associated with anterior wall ischemia or infarction in these patients.

Stroke volume calculated from the mitral valve echogram in patients with and without ventricular dyssynergy.

SUMMARY A formula was derived for calculating mitral valve stroke volume (MVSV) using the rate of mitral valve (MV) opening (DE slope on the MV echogram), the vertical distance between the mitral leaflet echoes early in diastole (EE), the electrocardiographic PR interval and heart rate. The formula was tested prospectively on 80 consecutive patients from whom 95 simultaneous MV echograms and either thermodilution (45) or Fick (50) cardiac outputs were obtained. Sixteen patients were normal; 54 had coronary artery disease; three had cardiomyopathy; and seven had nonrheumatic mitral regurgitation (MR). Linear regression for stroke volume was r = 0.90, SEE ± 6, and for cardiac output r = 0.83, SEE ± 0.5 liter for the 73 patients without MR. The presence or absence of ventricular dyssynergy did not alter statistical findings. MVSV consistently overestimated forward stroke volume for the seven patients with MR. This study shows that the MV echogram provides an accurate, widely applicable method for calculating MVSV.

Forward stroke volume calculated from aortic valve echograms in normal subjects and patients with mitral regurgitation secondary to left ventricular dysfunction.

Abstract A clinically applicable method was developed for calculating aortic valve stroke volume using the echocardiographically recorded initial and late aortic cusp separation, ejection time and amplitude of posterior aortic root motion during ejection. The formula was tested prospectively in 55 patients for whom 65 Fick [n = 26]or thermodilution [n = 39]cardiac output determinations were performed simultaneously with echocardiography. Aortic valve echograms were recorded in all patients and mitral valve echograms were also recorded in 48 of the 55 patients. Twenty patients had nonrheumatic mitral regurgitation. For the 65 studies, linear correlation (r) was excellent between the aortic valve method and Fick or thermodilution method for stroke volume (r = 0.96, standard error of the estimate [SEE]± 6 cc) and for cardiac output (r = 0.92, SEE ± 0.44 liters). Differences between cardiac output values obtained from aortic valve echograms and either Fick or thermodilution techniques ranged from −1.4 to +1.5 liters/min and were normally distributed. Ninety percent of the computed aortic valve data was within 15 percent of the Fick or thermodilution data. Aortic valve stroke volume correlated well (r = 0.93) with stroke volume derived from mitral valve echograms in the patients without mitral regurgitation but did not correlate well (r = 0.78) in the patients with mitral regurgitation. Mitral valve stroke volume exceeded aortic valve stroke volume by more than 20 percent in 19 of the 20 patients with mitral regurgitation compared with 1 of 28 patients without mitral regurgitation. The presence or absence of ventricular dyssynergy did not alter statistical findings. Data from this study show that (1) aortic valve echograms can be used clinically to measure forward stroke volume, and (2) the difference between mitral valve and aortic valve volume should be a measure of mitral regurgitant flow.