Decrease In Atrial Size Research Articles

Heart transplantation--surgical results.

Heart transplantation has become a widely used therapeutic option for the treatment of end-stage heart failure. Since the first human orthotopic heart transplant in the late 1960s, the surgical technique has undergone several revisions. These revisions have addressed certain anatomic and geometric distortions that occurred with the original biatrial technique of Lower and Shumway. Early revisions have included the use of a bicaval technique for implanting the right atrium. Subsequently, the additional use of a direct pulmonary venous anastomosis has lead to the surgical concept of the total orthotopic heart transplant. These revisions of the original bi-atrial technique have led to a decrease in atrial size and distortion, conduction abnormalities and tricuspid and mitral valve regurgitation. This has also resulted in less atrial thromboembolic events, less need for permanent postoperative pacemaker placement, and in an overall increase in right and left heart performance in the early postoperative period. Overall, this has contributed to better clinical results with patients returning sooner to their normal exercise capacity. Ninety percent of heart transplant patients lead a relatively normal lifestyle having no limitations in their activity and 40 % return to work. We believe that the technique of total orthotopic heart transplantation has improved surgical results and clinical outcomes.

Atrial anatomy and function postcardioversion: Insights from transthoracic and transesophageal echocardiography

Echocardiography provides a valuable tool for the evaluation and assessment of atrial function in patients with atrial fibrilation (AF). Atrial morphology after restoration of sinus rhythm is dynamic, with a decrease in atrial size if sinus rhythm is maintained and atrial growth among those with sustained AF. Restoration of electrocardiographic sinus rhythm is frequently accompanied by relatively depressed atrial mechanical function, with recovery that appears to be related to multiple factors, including the duration of AF before cardioversion and the mode of cardioversion. Such delay appears to confer ongoing risk for thrombus formation and thromboembolism in the days after cardioversion and argues strongly for the need to maintain therapeutic anticoagulation during the pericardioversion and postcardioversion period.

PLASMA ATRIAL NATRIURETIC FACTOR DURING ETHANOL INGESTION IN VOLUME-LOADED SUBJECTS

The present study was designed to test whether ethanol ingestion affects plasma atrial natriuretic factor (ANF) concentration in healthy volunteers. On the basis of previous studies showing that ethanol induces a diuretic response and a decrease in atrial size (atrial distension), it was hypothesized that ethanol intake might be associated with a decrease in plasma ANF level. To somewhat increase plasma ANF level, the subjects were slightly loaded with water before the trial. As compared with juice, ethanol, 1 g/kg within 1 hr, increased urine output [405 +/- 37 (mean +/- SEM) ml/hr vs. 197 +/- 20 ml/hr, P less than 0.001]. Left atrial size decreased similarly (P less than 0.001) with both drinks. Plasma ANF concentration did not change with either ethanol or juice during the 3-hr study period. No changes were observed in plasma arginine vasopressin concentration and plasma renin activity. Our results are in conflict with previous reports in fasted subjects showing significant changes in plasma concentrations of the same hormones. Thus, the basal fluid balance seems to be crucial to the hormonal response to ethanol. The plasma concentrations of the hormones measured in this study do not directly explain the diuretic response to ethanol observed in slightly volume-loaded subjects.

Effects of operation on left atrial size and the occurence of atrial fibrillation in patients with hypertrophic subaortic stenosis.

The relation between left atrial size and atrial fibrillation was examined in 37 patients who had left ventriculomyotomy and myectomy at the National Heart and Lung Institute. Atrial fibrillation was present in 11 of 27 (41%) patients with an echocardiographically measured left atrial dimension greater than 45 mm. No patient with a left atrial dimension less than 45 mm had atrial fibrillation pre or postoperatively. Eleven of 13 patients less than 40 years of age with an abnormal preoperative left atrial dimension had a 10% or greater reduction in left atrial dimension postoperatively. A group of 21 patients 40 years of age or older had an abnormal left atrial dimension preoperatively, and no significant change postoperatively. These results indicate that left ventriculomyotomy and myectomy can produce a significant decrease in left atrial size in younger patients with idiopathic hypertrophic subaortic stenosis. It is hoped that the decrease in atrial size may reduce the risk of atrial fibrillation in these patients.