Evaluation of calcium loss after transcatheter aortic valve implantation

Aortic valve calcification as a risk factor for major complications and reduced survival after transcatheter replacement

BACKGROUND

Aortic valve calcification is supposed to be a possible cause of embolic stroke or subclinical valve thrombosis after transcatheter aortic valve replacement (TAVR). We aimed to assess the role of aortic valve calcification in the occurrence of in-hospital clinical complications and survival after TAVR.

METHODS

We retrospectively analyzed preoperative contrast-enhanced multidetector computed tomography scans of patients who underwent TAVR on the native aortic valve in our center. Calcium volume was calculated for each aortic cusp, above and below the aortic annulus. Outcomes were recorded according to VARC-2 criteria.

RESULTS

Overall, 581 patients were included in the study (SapienXT = 192; Sapien3 = 228; CoreValve/EvolutR = 45; Engager = 5; Acurate = 111). Median survival was 4.98 years (interquartile range 4.41-5.54). Logistic regression identified calcium load beneath the right coronary cusp in left ventricular outflow tract (LVOT) as significantly associated with stroke (odds ratio [OR] 1.2; 95% confidence interval [CI] 1.03-1.3; p = 0.0019) and in-hospital mortality (OR 1.1; 95% CI 1.004-1.2; p = 0.04), whereas total calcium volume of the LVOT was associated with both in-hospital and 30 day-mortality (OR 1.2; 95% CI 1.01-1.4; p = 0.03, and OR 1.2; 95% CI 1.02-1.43; p = 0.029, respectively). Cox regression identified total calcium of LVOT (hazard ratio [HR] 1.18; 95% CI 1.02-1.38; p = 0.026), male sex (HR 1.88; 95% CI 1.06-3.32; p = 0.031), baseline creatinine clearance (HR 0.96; 95% CI 0.93-0.98; p < 0.001), and baseline severe aortic regurgitation (HR 7.48; 95% CI 2.76-20.26; p < 0.001) as risk factors associated with lower survival.

CONCLUSION

LVOT calcification is associated with increased risk of peri-procedural stroke and mortality as well as shorter long-term survival.

Calcification Characteristics of Low-Flow Low-Gradient Severe Aortic Stenosis in Patients Undergoing Transcatheter Aortic Valve Replacement

Low-flow low-gradient severe aortic stenosis (LFLGAS) is associated with worse outcomes. Aortic valve calcification patterns of LFLGAS as compared to non-LFLGAS have not yet been thoroughly assessed. 137 patients undergoing transcatheter aortic valve replacement (TAVR) with preprocedural multidetector computed tomography (MDCT) and postprocedural transthoracic echocardiography were enrolled. Calcification characteristics were assessed by MDCT both for the total aortic valve and separately for each leaflet. 34 patients had LFLGAS and 103 non-LFLGAS. Total aortic valve calcification volume (p < 0.001), mass (p < 0.001), and density (p = 0.004) were lower in LFLGAS as compared to non-LFLGAS patients. At 30-day follow-up, mean transaortic pressure gradients and more than mild paravalvular regurgitation did not differ between groups. In conclusion, LFLGAS and non-LFLGAS express different calcification patterns which, however, did not impact on device success after TAVR.