Prosthesis-patient mismatch after transcatheter aortic valve replacement: prevalence and medium term prognostic impact.

Prosthesis-patient mismatch (PPM) occurs when the effective orifice area of the prosthesis is too small in relation to the patient's body surface area. There are few data available on the frequency and prognostic impact of PPM after transcatheter aortic valve implantation (TAVI). Our aim was to determine the prevalence of PPM and to investigate its association with medium-term clinical course of patients undergoing TAVI. We included 185 patients undergoing TAVI (79 ± 5 years, 49% male, 98% CoreValve) between April-2008 and December-2014. The effective orifice area (EOA) was determined by transthoracic echocardiography prior and after the procedure. We defined PPM as indexed EOA ≤ 0.85 cm2/m2 (severe PPM if ≤ 0.65 cm2/m2). All cause death, stroke and hospitalization for heart failure were considered as major clinical events. 45 patients (24%) showed PPM (severe 11 patients, 6%). PPM was associated with a higher EuroSCORE (OR 1.06, IC 95% 1.01-1.12, p = 0.03), body surface area ≥ 1.72 m2 (OR 3.58, IC 95% 1.30-9.87, p = 0.01) and small aortic annulus (OR 0.73, IC 95% 0.55-0.92, p = 0.03); and severe PPM with small prostheses size (OR 17.79, IC 95% 1.87-169.78, p = 0.012). The mean event-free survival was 34 ± 26 months. Patients with severe PPM showed lower rates of event free survival than the rest of the series (52% vs. 84%, p = 0.04) at 34 months follow up. In our series, PPM was present in a quarter of the patients after TAVI. Higher EuroSCORE, smaller prosthesis size, larger body surface area and smaller aortic annulus diameter were associated with PPM. Severe PPM was an independent factor associated with major events at medium-term follow up.

Measurement of aortic valve annulus using different cardiac imaging techniques in transcatheter aortic valve implantation: agreement with finally implanted prosthesis size.

AIMS: To compare the measurements of the aortic annulus obtained with various imaging techniques in patients with severe aortic stenosis scheduled for transcatheter aortic valve implantation, and to determine the grade of agreement between the predicted size of the prosthesis for each technique, and the size of the finally implanted valve. METHODS AND RESULTS: The aortic annulus was measured in 40 patients treated by transcatheter aortic valve implantation (CoreValve aortic valve) with transthoracic (TTE) and transesophageal echocardiography (TEE), 64-slice tomography, and angiography. A large valve was implanted when annulus was >23 mm and a small one if it was ≤23 mm. If the size of the prosthesis predicted by several techniques was not the same in one case, we selected the size in which more techniques presented agreement. Forty aortic valves, 26 small and 14 large, were implanted percutaneously. The best correlation was obtained with TTE and TEE (r = 0.93, P < 0.001). The correlation of TTE and TEE with angiography also was good (r = 0.58, P < 0.001 and r = 0.53, P < 0.001, respectively). Correlations between these techniques and computed tomography were poor (P = NS for all comparisons). The best agreement between estimated aortic annulus and implanted valve size was obtained with transtoracic and TEE (κ= 0.88 and 0.76). CONCLUSIONS: The aortic annulus measurements obtained by TTE, TEE, and angiography correlated well, while tomography correlated poorly with other techniques. The imaging techniques that showed the best agreement between estimated aortic annulus size and implanted aortic valve size were TTE and TEE.