Surgery In Chronic Aortic Regurgitation Research Articles

A comparison of the clinical efficacy of echocardiography and magnetic resonance for chronic aortic regurgitation

Timing surgery in chronic aortic regurgitation (AR) relies mostly on echocardiography. However, cardiac magnetic resonance (CMR) may be more accurate for quantifying regurgitation and left ventricular (LV) remodelling. We aimed to compare the technical and clinical efficacies of echocardiography and CMR to account for the severity of the disease, the degree of LV remodelling, and predict AR-related outcomes. We studied 263 consecutive patients with isolated AR undergoing echocardiography and CMR. After a median follow-up of 33 months, 76 out of 197 initially asymptomatic patients reached the primary endpoint of AR-related events: 6 patients (3%) were admitted for heart failure, and 70 (36%) underwent surgery. Adjusted survival models based on CMR improved the predictions of the primary endpoint based on echocardiography: R2 = 0.37 vs. 0.22, χ2 = 97 vs. 49 (P < 0.0001), and C-index = 0.80 vs. 0.70 (P < 0.001). This resulted in a net classification index of 0.23 (0.00-0.46, P = 0.046) and an integrated discrimination improvement of 0.12 (95% confidence interval 0.08-0.58, P = 0.02). CMR-derived regurgitant fraction (<28, 28-37, or >37%) and LV end-diastolic volume (<83, 183-236, or >236 mL) adequately stratified patients with normal EF. The agreement between techniques for grading AR severity and assessing LV dilatation was poor, and CMR showed better reproducibility. CMR improves the clinical efficacy of ultrasound for predicting outcomes of patients with AR. This is due to its better reproducibility and accuracy for grading the severity of the disease and its impact on the LV. Regurgitant fraction, LV ejection fraction, and end-diastolic volume obtained by CMR most adequately predict AR-related events.

Prognostic value of preoperative indexed end-systolic left ventricle diameter in the outcome after surgery in patients with chronic aortic regurgitation

End-systolic diameter (ESD) is an important parameter in the prognosis and indication for surgery in chronic aortic regurgitation (AR). It has been suggested that ESD values noncorrected for body surface area (BSA) could be inappropriate in the management of patients with extreme BSA. The aim of the study was to assess the usefulness of indexed ESD (IESD) of the left ventricle in the management of patients with severe isolated chronic AR. One hundred forty-seven patients underwent surgery for chronic AR and were followed up for a mean of 8 +/- 6 years (1-22 years). A post hoc assessment was made of the prognostic value of preoperative ESD and IESD in different BSA percentiles: group 1, <or= 25th percentile (BSA 1.43-1.68 m(2), n = 40); group 2, >25th percentile and <or=75th percentile (BSA 1.69-1.91 m(2), n = 68); and group 3, >75th percentile (BSA 1.92-2.24 m(2), n = 39). Age-adjusted preoperative ESD and IESD were independent predictors of mortality or heart failure in the entire population. Magnitude of the relative risk was slightly greater using preoperative IESD than ESD (HR 1.07, 95% CI 1.01-1.29, P = .017; HR 1.04, 95% CI 1.01-1.08, P = .016). In group 1, the age-adjusted expected mortality rate would drop if IESD of 25 mm/m(2) was used as a surgical criterion instead of ESD 50 mm, from 37.94% to 24.27% at 10 years (P = .002). The use of IESD improves the prediction of unfavorable outcomes after surgery in patients with low BSA but not in those with high BSA. In patients with low BSA, IESD >or=25 mm/m(2) should be used as a cutoff point for surgery rather than ESD >50 mm.

Improved Outcomes After Aortic Valve Surgery for Chronic Aortic Regurgitation With Severe Left Ventricular Dysfunction

Among patients undergoing aortic valve surgery for chronic aortic regurgitation (AR), we sought to: 1) compare survival among those with and without severe left ventricular dysfunction (LVD); 2) identify risk factors for death, including LVD and date of operation; and 3) estimate contemporary risk for cardiomyopathic patients. Patients with chronic AR and severe LVD have been considered high risk for aortic valve surgery, with limited prognosis. Transplantation is considered for some. From 1972 to 1999, 724 patients underwent surgery for chronic AR; 88 (12%) had severe LVD. They were propensity matched to patients with nonsevere LVD to compare hospital mortality, interaction of operative date with severity of LVD, and late survival. Propensity score-adjusted multivariable analysis was performed for all 724 patients to identify risk factors for death. Survival was lower (p = 0.04) among patients with severe LVD than among matched patients with nonsevere LVD (30-day, 1-, 5-, and 25-year survival estimates were 91% vs. 96%, 81% vs. 92%, 68% vs. 81%, and 5% vs. 12%, respectively). However, survival of patients with severe LVD improved dramatically across the study time frame (p = 0.0004): hospital mortality decreased from 50% in 1975 to 0% after 1985, and time-related survival in patients with severe LVD operated on since 1985 became equivalent to that of matched patients with nonsevere LVD (p = 0.96). Neutralizing risk of severe LVD has improved early and late survival such that aortic valve surgery for chronic AR and cardiomyopathy is no longer a high-risk procedure for which transplantation is the best option.

851-4 Changing outlook after aortic valve surgery for chronic aortic regurgitation with severe left ventricular dysfunction

851-4 Changing outlook after aortic valve surgery for chronic aortic regurgitation with severe left ventricular dysfunction

Timing of surgery in chronic aortic regurgitation.

When deciding on therapy for aortic regurgitation (AR), it is imperative to distinguish between acute and chronic AR. Symptoms and echocardiographic findings are essential in distinguishing acute from chronic AR and in assessing the severity. Vasodilators have been shown to be helpful in treating patients with chronic severe AR. The timing of aortic valve replacement in chronic severe AR remains controversial. Symptoms, left ventricular function, and response to exercise have been shown to be the most important prognostic indicators.

Clinical evaluation of a prospective protocol for the timing of surgery in chronic aortic regurgitation

Out of 160 prospectively followed patients with aortic regurgitation, the clinical courses of 53 patients with pure, severe, and chronic aortic regurgitation and without coronary artery disease who were selected for surgery on the basis of predefined criteria is discussed. Surgical criteria were either unequivocal symptoms or documentation of impaired left ventricular dysfunction (defined as angiographic ejection fraction of less than 50% plus and end-systolic volume index greater than 60 ml/m 2). According to preoperative status, patients were divided as follows: 11 asymptomatic patients (group A), 30 patients with moderate (classes II to III) symptoms (group B), and 12 patients with dyspnea at rest and pulmonary edema when first seen (group C). Surgical mortality was one patient (from group C). Late death occurred in four patients (one from group B, three from group C). At the end of follow-up (minimum 1 year, mean 3.6 years) 41 patients were in functional class I, four patients in class II, and one patient in class III. All patients except one in functional classes II and III belonged to group C. Before surgery, patients from groups A and B had similar ventricular dimensions and ejection fractions, whereas patients from group C had larger end-systolic diameters and volumes and lower ejection fractions. End-diastolic and end-systolic diameters decreased significantly at 1 and 2 years after surgery. Patients from group C continued to have dilated hearts as did those patients from groups A and B who had preoperative end-systolic diameters greater than 55 mm. Radionuclide ejection fraction increased in most patients with preoperative values less than 50%, except in those with preoperative values less than 30%. Our results suggest that in asymptomatic patients, surgery can be delayed at least until our criteria for left ventricular dysfunction are reached. Although the postoperative outcome of patients with preoperative severe heart failure was not as good as that of other patients, symptomatic improvement is likely to occur even in cases of severely impaired left ventricular function.

Irreversible morphological changes contributing to depressed cardiac function after surgery for chronic aortic regurgitation.

The timing of surgery in chronic aortic regurgitation remains a difficult problem. To identify variables predictive of postoperative haemodynamic improvement, changes in left ventricular mass, volume, morphology, and histochemistry were analysed in 67 patients undergoing surgery for chronic aortic regurgitation. Patients were divided into two groups: those in whom the left ventricular echo diameters returned to normal after operation (51 patients, group A), and those with postoperative dilatation (16 patients, group B). A preoperative biopsy was obtained in all patients; postoperative tissue samples were available in 13 patients (five from group A, eight from group B). Data were correlated with the postoperative clinical, haemodynamic state over a follow-up period of three years. Regression of hypertrophy was usually incomplete. Echocardiographic and angiographic data could not define the type and degree of dysfunction which was irreversible. Massive fibre hypertrophy (mean 34.1 micrometers), moderately or severely increased interstitial fibrous tissue, reduced levels of the myofibrillar and mitochondrial enzymes adenosine triphosphates and succinate dehydrogenase in pre- and post-operative tissue samples correlated with persistent dilation, cardiac failure, and early death (group B). Irreversible morphological and functional changes contributed to a depressed cardiac function after operation. Preoperative ventricular biopsies are thus of prognostic importance in volume overload.