Chronic Aortic regurgitation (AR) still presents a considerable prevalence among heart valve diseases, especially in regions with high frequency of rheumatic disease. The main triggers of surgical treatment are the development of symptoms and/or left ventricular dysfunction. Surgical intervention based exclusively on ventricular diameters still remains controversial. This study stands out for bringing the longest period of follow-up already reported for patients with AR.
Prospective study of 73 patients with chronic severe AR, followed during a mean period of 28.8 ± 2.6 years. Surgical treatment was determined by the appearance of symptoms and/or systolic dysfunction of the left ventricle (LV), defined by ejection fraction < 0.5 or LV end systolic diameter > 55 mm. All patients underwent transthoracic echocardiography during follow-up. Continuous variables were expressed as mean ± standard deviation. Categorical variables were expressed as proportions. Chi-square test and t test were used in the univariated analysis. Projections of survival were determined by Kaplan-Meier curves.
The main cause of AR was rheumatic cardiac disease (94%), with predominance in men (73%). At the beginning of follow-up, 22 (30%) of patients were symptomatic. Surgical treatment was performed in 52% of patients and consisted mainly in aortic valve replacement using bioprosthesis (92% of the procedures). The overall mortality was 15%. The study showed a higher long-term mortality in the surgical group than in the clinical group (26% versus 2.9%, p 0.007. Relative risk =9.2, CI 1.35 - 191.8), mainly due to late prosthesis dysfunction and postoperative complications in prosthesis re-replacement surgery (cardiogenic shock, bleeding, infection). Patients that remained in clinical treatment, mainly due to the absence of symptoms or ventricular dysfunction, exhibited a low long-term mortality rate (2.9%), despite of LV remodeling (mean LV end diastolic diameter of 65.8 ± 6.9 mm, mean LV systolic diameter of 40.3 ± 5.2 mm). Reoperation was performed in 40% of patients and was a mortality predictor on the univariated analysis (Relative Risk= 6.1, p= 0.006).
The present study, based on the longest follow-up period reported for rheumatic AR, found no mortality registry in the asymptomatic AR, demonstrating a favorable prognosis for this subgroup of patients, even with LV remodeling. Surgical treatment, although necessary for symptomatic patients or with left ventricular dysfunction, is associated with higher long-term morbidity and mortality related to prosthetic dysfunction.