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Study of posterior left atrial wall motion by echocardiography and its clinical application
Insights
Echocardiography of posterior left atrial wall motion reveals distinct wave patterns. Abnormalities in A and V waves, indicated by an increased A/V ratio, help detect mitral stenosis and reduced left ventricular filling.
Area of Science:
- Cardiology
- Echocardiography
- Cardiac Physiology
Background:
- The posterior left atrial wall motion provides insights into cardiac dynamics.
- Understanding normal and abnormal wave patterns is crucial for diagnosing cardiac conditions.
Purpose of the Study:
- To investigate the echocardiographic characteristics of posterior left atrial wall motion.
- To assess the utility of these findings in identifying mitral stenosis and coronary artery disease.
Main Methods:
- Echocardiographic tracings of posterior left atrial wall motion were analyzed.
- 30 normal subjects, 17 with mitral stenosis, and 31 with coronary artery disease were studied.
Main Results:
- Normal tracings show distinct A, C, V, X, and Y waves.
- Mitral stenosis and coronary artery disease patients exhibited increased A wave excursion and decreased V wave excursion (p < 0.01).
- The A/V ratio was significantly increased, and the V wave's ascending limb slope decreased in both patient groups (p < 0.01).
Conclusions:
- Echocardiographic assessment of posterior left atrial wall motion is feasible.
- Abnormalities in A/V ratio and V wave slope are indicative of mitral stenosis or reduced left ventricular filling rate.
- This technique aids in estimating the presence of these cardiac conditions.
Abstract:
Echocardiographic tracings of posterior left atrial wall motion were examined in 30 normal subjects, 17 patients of mitral stenosis with sinus rhythm and 31 coronary patients with elevated left ventricular end-diastolic pressure. Because of the plane of the posterior left atrial wall motion and the angle of the sound beam, usually the postero-inferior portion of the left atrial wall was recorded. In normal subjects, there were 3 positive waves (A,C,V waves) and 2 negative waves (X and Y waves). The A wave during atrial contraction period occurred in the closing motion of the mitral valve and was initiated by a slight negative wave. The fourth heart sound was consistent with the ascending limb of the A wave. The C wave coincided with the first heart sound followed by the pronounced negative depression (X wave). The X trough coincided with the beginning of the mitral valve opening in early diastole and was the deepest point in the motion curve. The V wave was a peaked anterior motion during rapid filling period and followed by the third heart sound. The Y wave was a slight negative depression following the V wave, and its trough occurred when the both leaflets of the mitral valve assumed a semiclosed position. In both mitral stenosis and coronary artery disease, significant increase (p less than 0.01) of the A wave excursion and significant decrease (p less than 0.01) of the V wave excursion were observed, resulting in marked increase (p less than 0.01) of the A/V ratio. The slope of the ascending limb of the V wave was also decreased apparently in both conditions. These findings might reflect increased resistance to left atrial emptying in mitral stenosis and decreased left ventricular filling rate in coronary artery disease. This study shows that echocardiographic examination of the posterior left atrial wall motion is feasible and useful in estimating the presence of either mitral stenosis or decreased left ventricular filling rate.