Multidetector CT predictors of prosthesis–patient mismatch in transcatheter aortic valve replacement

BackgroundProsthesis–patient mismatch (PPM) is a predictor of mortality after aortic valve replacement (AVR).ObjectiveWe examined whether accurate 3-dimensional annular sizing with multidetector CT (MDCT) is predictive of PPM after transcatheter AVR (TAVR).MethodsOne hundred twenty-eight patients underwent MDCT then TAVR. Moderate PPM was defined as an indexed effective orifice area ≤0.85 cm2/m2 and severe ≤0.65 cm2/m2. MDCT annular measurements (area, short and long axis) were compared with the size of the selected transcatheter heart valve (THV) to obtain (1) the difference between prosthesis size and CT-measured mean annular diameter and (2) the percentage of undersizing or oversizing (calculated as 100 × [MDCT annular area – THV nominal area]/THV nominal area). In addition, the MDCT annular area was indexed to body surface area. These measures were evaluated as potential PPM predictors.ResultsWe found that 42.2% of patients had moderate PPM and 9.4% had severe PPM. Procedural characteristics and in-hospital outcomes were similar between patients with or without PPM. THV undersizing of the mean aortic annulus diameter was not predictive of PPM (odds ratio [OR], 0.84; 95% CI, 0.65–1.07; P = .16; area under the receiver-operating characteristic curve [AUC], 0.58). THV undersizing of annular area was not predictive of PPM (OR, 0.96; 95% CI, 0.80–1.16; P = .69; AUC, 0.52). Indexed MDCT annular area was, however, predictive of PPM (OR, 0.24; 95% CI, 0.10–0.59; P < .001; AUC, 0.66).ConclusionsPPM is frequent after TAVR. Appropriate annular oversizing does not reduce the rate or severity of PPM. Patient annulus size mismatch, identified by indexed MDCT annular area, is a significant predictor of PPM.