Outcomes following surgical correction of pure aortic regurgitation in presence or absence of significant functional mitral regurgitation.

BACKGROUND: Functional mitral regurgitation (MR) can occur secondary to severe aortic regurgitation (AR). However, data on the overall impact of mitral surgical intervention after aortic valve replacement (AVR) are scarce. We sought to study the left ventricular (LV) remodeling process and determine predictors of clinical outcomes of patients with pure severe AR in presence or absence of significant functional MR. METHODS: Patients were categorized into AR-MR group (≤ mild MR; n = 51, 76%) and AR + MR group (≥ moderate MR; n = 16, 24%). All patients in the AR + MR group underwent AVR and MR correction. Serial echocardiographic measurements and clinical follow-up up to 5 years were obtained in all patients. RESULTS: Significant reverse LV remodeling occurred in both groups compared with baseline. No 30-day deaths occurred. Mortality and heart failure-related hospitalization rates, at follow-up, were significantly higher in the AR + MR group (19% vs. 2%, P = 0.04 and 38% vs. 12% P = 0.03, respectively), but a similar proportion of patients from both groups was in New York Heart Association class I or II (87% vs. 92%, P = 0.62). Preoperative indexed stroke volume (SV) <50 mL/m2 was the only independent predictor of death and/or rehospitalization after surgery (odds ratio: 61.1, [95% CI, 12.6­425.2]; P < 0.0001). CONCLUSION: Despite being a higher risk population, patients with moderate-to-severe functional MR secondary to severe AR experience similar postoperative mortality at the expense of a moderately higher 5-year overall mortality, rate of hospitalization for congestive heart failure, and medication use. Preoperative indexed SV < 50 mL/m2 may be helpful in predicting long-term outcomes.

Predictors of left ventricular remodeling after surgical repair or replacement for pure severe mitral regurgitation caused by leaflet prolapse.

We sought to determine whether preoperative baseline echocardiographic analysis and the type of surgical procedure are predictive of the magnitude and timing of postoperative left ventricular (LV) remodeling in patients undergoing valve surgery for pure severe mitral regurgitation (MR) secondary to leaflet prolapse. Seventy-two consecutive patients without coronary artery disease undergoing valve repair (MVr; n = 42) or replacement (MVR; n = 30) underwent preoperative, early (1 to 2 days) and late postoperative (4.5 ± 2.5 and 18 ± 8.0 months) echocardiography. Patients were categorized according to their baseline LV ejection fraction (EF) (Group 1: EF ≥60%, Group 2: EF = 50% to 59%, Group 3: EF <50%). Preservation of the subvalvular apparatus was achieved in most patients undergoing MV replacement (87%). Over a median follow-up period of 450 days, LVEF changed as follows: Group 1: 63% ± 2% to 60% ± 3% (p <0.0001); Group 2: 55% ± 3% to 52% ± 6% (p <0.0001); Group 3: 43% ± 4% to 42% ± 5% (p <0.01). Two-thirds of the observed changes in LV diameters and volumes occurred in the first 6 months. Preoperative LVEF was the best predictor of postoperative LVEF ≥60% (odds ratio 1.50, 95% confidence interval, 1.25 to 1.97; p <0.0001). No significant difference was found in LV remodeling parameters between patients undergoing MVr and MVR. In conclusion, patients with pure severe MR due to valve prolapse LVEF remained normal after surgery only in patients with baseline LVEF ≥60%. MVR with subvalvular preservation was associated with similar postoperative remodeling as MVr.

Usefulness of preoperative stroke volume as strong predictor of left ventricular remodeling and outcomes after aortic valve replacement in patients with severe pure aortic regurgitation.

In most patients with aortic regurgitation (AR), aortic valve replacement (AVR) results in favorable left ventricular (LV) remodeling and normalization of the LV ejection fraction (EF). However, some patients with severe AR will not have favorable remodeling and their LVEF will not normalize. The goal of the present study was to determine whether remodeling and clinical outcomes after AVR could be predicted from simple preoperative echocardiographic analysis. A total of 56 consecutive patients with chronic severe pure AR who underwent AVR had preoperative (5 ± 2 days), early postoperative (5 ± 2 days), and late postoperative (328 ± 88 days) echocardiographic data retrospectively analyzed. The LV diameter, The LVEF and stroke volume (SV) were measured. The reduction in LV end-diastolic dimension decreased by 14% (from 65 ± 6 mm to 56 ± 8 mm, p <0.001) early after AVR, with an additional reduction of only 6% late after AVR. More than 2/3 of the overall reduction in end-diastolic dimension was observed the week after AVR. Forty-six patients (82%) had positive early LV remodeling, defined as a 10% reduction in the LV end-diastolic diameter 1 week after AVR. All patients with early LV remodeling had a preoperative SV of ≥97 ml, which was the best predictor of late postoperative LVEF of ≥45% (sensitivity 98% and specificity 100%). Patients with a preoperative SV of ≥97 ml had a markedly greater event-free survival rate (92% vs 13%, p <0.001) at 3 years. In conclusion, in patients undergoing AVR for chronic severe pure AR, preoperative SV is the best predictor of LV remodeling and outcomes.