Factors affecting left ventricular mass regression after aortic valve replacement with stentless valves

The hemodynamic benefits of using stentless valves for replacement of the human aortic valve have become more well known. These devices are associated with significant decrease in left ventricular (LV) mass and LV remodeling in the early postoperative period. However, no large study has examined patient-related and valve-related factors that may contribute to this phenomenon. This study examined 1,103 patients who underwent aortic valve replacement (AVR) with a stentless porcine valve (Freestyle = 840, SPV = 263). In all cases, a subcoronary implant technique was used. Valve performance was assessed by serial echocardiograms. At 3 years' post-AVR, mean gradient was 6.3+/-5.0 mm Hg, and effective orifice area (EOA) was 2.0+/-0.7 cm2. Indexed EOA was 1.2+/-0.4 cm2/m2. There was an association between indexed EOA and the extent of LV mass regression. At 3 years after surgery, LV mass index (LVMI) was reduced to 76.3% to 78.7% of baseline in patients whose indexed EOA was >0.8 cm2/m2. In contrast, for patients with an indexed EOA that was <0.8 cm2/m2, LVMI at 3 years was 95.5% of baseline (P = .0001). Multiple linear regression models were used to identify parameters that predicted the 3-year LVMI. Baseline LVMI (P<.0001), prior myocardial infarction (P = .0009), male gender (P = .0036), and carotid stenosis (P = .022) were independent predictors of LV mass regression. Valve type, valve size, preoperative New York Heart Association class symptoms, coronary disease, prior bypass surgery, chronic obstructive pulmonary disease, or underlying valve pathology had no effect on LV mass regression. Data indicate that baseline LVMI and patient-prosthetic mismatch have major effects on the extent of LV mass regression post-AVR. Long-term hemodynamic benefits of AVR can be optimized by proper selection of the prosthesis so as to avoid mismatch. Furthermore, because the baseline LVMI affects the extent of regression post-AVR, early intervention may result in more complete resolution of LV mass postoperatively, which may have important prognostic implications.