Timing of valve replacement in patients with chronic aortic regurgitation.

Abstract

WHEN TO RECOMMEND aortic valve replacement for mildly symptomatic or asymptomatic patients with moderate-to-severe aortic regurgitation is a difficult clinical problem. Severe chronic aortic regurgitation is associated with a generally favorable prognosis.1' 2 Approximately 75% of the patients are alive 5 years and 50% 10 years after the diagnosis.2 However, when symptoms develop, the patient's condition often deteriorates rapidly. Without surgery, the patient usually dies within 5 years after the onset of angina and 2 years after developing heart failure. In this issue of Circulation, Henry and associates report the results of serial M-mode echocardiographic studies in 50 consecutive symptomatic patients who underwent aortic valve replacement for isolated, moderate-to-severe aortic regurgitation.10' 11 In these studies, several echocardiographic indices were predictive of late death due to congestive heart failure in symptomatic patients who underwent otherwise successful aortic valve replacement. Specifically, a preoperative LV end-systolic dimension (ESD) of > 55 mm and percent fractional dimension shortening (%,AD) < 25% indicated an increased incidence of perioperative morbidity and late postoperative congestive heart failure and death compared with patients with similar symptoms but less depressed LV systolic function. A combination of the two findings (ESD > 55 mm and %zAD < 25%) was the most powerful predictor; 11 of 13 patients (85%) with these findings either died (nine patients) or had evidence of severe congestive heart failure postoperatively. Five of the nine deaths occurred in the immediate postoperative period. This high perioperative mortality risk may not be applicable to patients currently undergoing aortic valve replacement, owing to newer operative techniques for preserving myocardial function.The data of Henry and associates are consistent with the LV cineangiographic studies by Borow and co-workers,8 who found that the immediate and longterm results of aortic valve replacement were poor in the patients in whom the LV end-systolic volume index was markedly elevated (> 90 ml/m2). In the latter study the preoperative LV ejection fraction was of less predictive value. In contrast, Clark and associates reported no perioperative mortality in 17 patients with symptomatic aortic regurgitation and impaired LV performance.9 Also, they found no difference in late mortality in patients with a preoperative cineangiographic end-systolic volume of > 110 ml/m2 compared with those who had a smaller end-systolic volume. However, the 5-year survival in patients with an ejection fraction of < 45% was 33 ± 19%, compared with 94 ± 6% (p < 0.001) in those with an ejection fraction > 45%. However, not all patients with preoperative impairment of LV performance do poorly after aortic valve replacement; late postoperative LV systolic function improves in as many as 50% of the patients.5-9Henry and co-workers also reported serial M-mode echocardiographic data in 37 initially asymptomatic patients with aortic regurgi...

Afterload mismatch and preload reserve in chronic aortic regurgitation.

“…Patients in group 2 had a lower LV ejection fraction and velocity of circumferential fiber shortening than those in group 1 at a similar lower level of afterload. At a similar higher level of afterload, which increased end-diastolic volume from 134 4 to 157 + 6ml/m2 in group 1 and from 191 + 9 to 218 13 ml/m2 in group 2 (average increase 18% vs 14%, NS), patients in group 1 maintained their ejection fraction and forward stroke volume and had a significant increase in total LV stroke volume, whereas patients in group 2 had a decrease in ejection fraction and in forward stroke volume and no significant change in LV stroke volume. The velocity of circumferential fiber shortening decreased in both groups in response to increased afterload.…”

Determination of the Anaerobic Threshold in the Evaluation of Functional Status before and following Valve Replacement for Aortic Regurgitation

“…Angulation of the trans ducer, the shape and size of the left ventricle, and the patient's position may result in a considerable variation in LV dimensions [16], No attempt was therefore made to cor relate the echocardiographic and angio graphic LV measures. As regards the repro ducibility of the echocardiographic dimen sions, the mean differences between dupli cate measurements of EDD and ESD were 1.8 and 1.6 mm, respectively, in a previous study at our laboratory [17], which suggests that test-to-test variability is unlikely to af fect our conclusions.…”

Echocardiographic evaluation of the response to afterload stress test in young asymptomatic patients with chronic severe aortic regurgitation: sensitivity of the left ventricular end-systolic pressure-volume relationship.

“…4, 561-569, 1984. IT IS generally agreed that aortic valve replacement for between contractility and loading conditions at rest patients with chronic severe aortic regurgitation should and during exertion can account for this apparent disnot always be delayed until the appearance of severe crepancy.7 8 Nevertheless, myocardial dysfunction, symptoms. [1][2][3][4][5][6] An impairment of myocardial contractilwhether or not it is associated with severe symptoms, ity can be present even in the absence of significant can be irreversible, preventing improvement or adsymptoms in these patients. The 19 The changes in stroke volume index and ejection fraction at the peak pressure effect of angiotensin were used to evaluate the response to afterload stress.…”