Prevalence and Impact of Prosthesis-Patient Mismatch Following Surgical Aortic Valve Replacement for Pure Aortic Regurgitation.

ABSTRACT

BACKGROUND: Prosthesis-patient mismatch (PPM) is highly prevalent among patients undergoing aortic valve replacement (AVR) to treat aortic stenosis. Data regarding the prevalence and impact of PPM on left ventricular remodeling and outcomes in patients who have undergone surgical AVR to treat pure severe aortic regurgitation (AR) are, however, scarce. METHODS: A retrospective analysis was conducted of clinical and echocardiographic data acquired from 50 consecutive patients with pure severe AR, without evidence of significant coronary artery disease, who underwent AVR between 2004 and 2010 at the authors' institution. PPM was defined as a projected in vivo effective orifice area (EOA) 0.85 cm2/m2. RESULTS: The incidence of PPM was 16%, but no severe mismatch occurred. At a mean follow up of 52 ± 39 months, event-free survival (a composite of all-cause mortality and hospitalization for cardiovascular causes) was similar between patients with and without PPM (p = 0.73). Within seven days after surgery, mean reductions in indexed left ventricular end-diastolic diameter (LVEDD) and indexed left ventricular end-systolic diameter (LVESD) were similar between patients with and without PPM [4.4 mm/m2 versus 5.0 mm/m2; p = 0.67 and 1.6 mm/m2 versus 2.2 mm/m2; p = 0.35, respectively]. At follow up, no difference was observed for mean reductions in indexed LVEDD and indexed LVESD [6.9 mm/m2 versus 7.1 mm/m2; p = 0.91 and 4.1 mm/m2 versus 5.1 mm/m2; p = 0.57, respectively], and mean improvement in left ventricular ejection fraction (4.4% versus 5.1%; p = 0.87). CONCLUSIONS: PPM occurs less frequently in patients undergoing AVR for pure severe AR than for aortic stenosis, and seems to have a less significant impact on ventricular remodeling and outcomes.