Effect of Cardiac Rehabilitation on Atrial Function in Patients with Acute Anterior Wall Myocardial Infarction Following Successful Coronary Revascularization

Abstract

Atherosclerotic cardiovascular disease is now the leading cause of death worldwide and there is overwhelming evidence that comprehensive cardiac rehabilitation is associated with a reduction in both cardiac mortality and total mortality so there is an increasing interest in studying the effect of cardiac rehabilitation in ischemic patients and how to get the maximum benefit from the rehabilitation program. The left atrium plays a major role in left ventricle performance as it is an important marker of LV diastolic dysfunction so assessment of LA size and function provides prognostic data for the outcome of patients with MI or ischemia. This study aimed to assess the effect of cardiac rehabilitation on both atrial function assessed by Speckle tracking in patients with acute anterior STEMI. Our study included 50 patients divided into two equal groups, Group A who participated in the program, 2 sessions per week for 3 months and group B who did not participate in the program. All data available for the patients were collected including history, ECG, Cardiac enzymes, angiographic data, Baseline ECHO was done for all patients during the hospital stay with assessment of LV systolic and diastolic function, LA volume and peak systolic strain, Right atrial volume, dimensions and strain and they underwent also symptom limited exercise test to assess the basic functional capacity 2 weeks after the infarction. Group A had cardiac rehabilitation program, 2sessions per week for 12 weeks with the exercise intensity based on Heart rate Reserve HRR, in addition to exercise the program included counseling, education about stress management, smoking cessation, nutrition and weight loss while the other group did not participate in the program. After 3 months, ECHO with assessment of the same parameters and symptoms limited exercise test were repeated for all patients and we found that: LVEF assessed by modified Simpson method improved significantly in both groups with marked improvement in the rehabilitation group compared to the non-rehabilitation one. E/A ratio and E/e' showed marked improvement in group A after the program with no significant change in group B. LA peak systolic strain and the mean strain representing the left atrial function improved significantly in the rehabilitation group while it showed no improvement in the other group. No obvious effect of cardiac rehabilitation program on Right atrial volume and function according to this study. There was marked improvement of the exercise capacity and total exercise time in the rehabilitation group. And according to the results of this study we emphasize the positive effect of the cardiac rehabilitation program on left atrial function which plays a major role in cardiac mortality through its effect on left ventricular performance and also affects all-cause mortality as atrial arrhythmias increase the risk of stroke.