Aortic Valve Calcium Volume Predicts Paravalvular Regurgitation and the Need for Balloon Post-Dilatation After Transcatheter Aortic Valve Implantation.

OBJECTIVE

This study sought to evaluate the impact of aortic valve (AV) and left ventricle outflow tract (LVOT) calcium on paravalvular regurgitation (PVR) and need for balloon post-dilatation (BPD) during transcatheter aortic valve implantation (TAVI).

METHODS

The overall study population comprised 152 patients. Calcium mass and volume of AV and LVOT were estimated from contrast-enhanced multislice computed tomography imaging, using 3 thresholds for calcium detection [650, 850, and 1,050 Hounsfield units (HU)].

RESULTS

A self-expandable prosthesis was implanted in 67.8% of patients and a balloon-expandable prosthesis in the remaining. Eleven patients required BPD and 82 patients presented post-procedural PVR, which was mild in 44.1% and moderate in 9.9%. The greatest discriminatory value for PVR ≥ mild was seen for calcium volume using 850 HU threshold, with an area under the curve of 0.72 (95%CI 0.64-0.80, P < 0.001) for AV and of 0.63 (95%CI 0.54-0.72, P = 0.008) for LVOT. For 850 HU threshold, the calcium volume cut-off with the highest sum of sensitivity and specificity for PVR was 157 mm(3) for AV and 0.6 mm(3) for LVOT. In multivariate logistic regression analysis, the presence of AV calcium ≥157 mm(3) (OR 3.83, 95%CI 1.81-8.10, P < 0.001) and ≥267 mm(3) (OR 11.3, 95%CI 1.2-103.1, P = 0.03) were the only independent predictors of PVR and BPD, respectively.

CONCLUSIONS

AV calcium volume was an independent predictor of PVR and BPD in patients submitted to TAVI. Our results support a systematic assessment of AV calcium volume to identify patients at increased risk of post-procedural PVR.