Log in to MyACC
Bioprosthetic AVR Calcification and Outcomes
Quick Takes
- Bioprosthetic aortic valve calcification density (AVCd) is associated with subsequent hemodynamic valve deterioration, and with increased risk of mortality and re-intervention.
- The combination of AVCd and echo/Doppler mean gradient progression identified patients at high risk for adverse outcomes.
Study Questions:
How does bioprosthetic aortic valve leaflet calcification, quantified using multidetector computed tomography (MDCT), correlate with hemodynamic and clinical outcomes?
Methods:
From 2008 to 2010, a total of 204 patients were prospectively enrolled a median of 7.0 years (interquartile range, 5.1-9.2 years) after surgical bioprosthetic aortic valve replacement (AVR). Aortic valve calcification (AVC) measured using the Agatston method on MDCT was indexed to the cross-sectional area of aortic annulus measured by echocardiography to calculate the AVC density (AVCd). The presence of hemodynamic valve deterioration (HVD; defined by an increase in mean gradient [MG] ≥10 mm Hg and/or increase in transprosthetic regurgitation ≥1 grade) was assessed by echocardiography in 137 patients at the 3-year follow-up. The primary clinical endpoint was mortality or aortic valve re-intervention.
Results:
There was no significant sex-related difference in the relationship between bioprosthetic AVCd and the progression of the MG. Baseline AVCd showed an independent association with HVD at 3 years. During follow-up, there were 134 (65.7%) deaths (n = 100) or valve re-interventions (n = 47). AVCd ≥58 AU/cm2 was independently associated with an increased risk of mortality or aortic valve re-intervention (adjusted hazard ratio, 2.23; 95% confidence interval, 1.44-3.35; p < 0.001). The AVCd threshold combined with MG progression threshold of 10 mm Hg amplified the stratification of patients at risk (log-rank p < 0.001). The addition of AVCd threshold into a prediction model including traditional risk factors improved outcome prediction (net classification improvement 0.25, p = 0.04, likelihood ratio test p < 0.001).
Conclusions:
Aortic bioprosthetic leaflet calcification is strongly and independently associated with HVD and the risk of death or aortic valve re-intervention. As opposed to native aortic stenosis (AS), there are no sex-related differences in the relationship between AVCd and hemodynamic or clinical outcomes.
Perspective:
Among patients with native AS, AVC is a marker of stenosis severity, with utility in confirming AS severity in the setting of low gradient AS (1,200 AU in women, 2,000 AU in men); and AVCd has been shown to be a predictor of AS progression and outcomes, albeit again with different thresholds in women (>300 AU/cm2) than in men (>500 AU/cm2). Bioprosthesis SVD is a progressive process with leaflet thickening, calcification, fibrosis, and tear; leading to structural dysfunction. This study demonstrates that bioprosthetic AVR calcification is strongly associated with HVD and the risk of death or re-intervention, but without a sex-related difference in the association between AVCd and outcomes. The combination of echo/Doppler MG progression and MDCT AVCd identified patients at high risk for adverse outcomes. This study suggests that a strategy that employs multimodality imaging, including for echo/Doppler and MDCT, could help stratify patient risk following bioprosthetic AVR. Future studies would need to confirm the findings, and address whether earlier re-do intervention based on echo/Doppler plus MDCT data can result in improved patient outcomes.
Clinical Topics: Cardiac Surgery, Invasive Cardiovascular Angiography and Intervention, Noninvasive Imaging, Valvular Heart Disease, Aortic Surgery, Cardiac Surgery and VHD, Interventions and Imaging, Interventions and Structural Heart Disease, Computed Tomography, Echocardiography/Ultrasound, Nuclear Imaging
Keywords: Aortic Valve Stenosis, Bioprosthesis, Calcification, Physiologic, Cardiac Surgical Procedures, Cardiology Interventions, Constriction, Pathologic, Diagnostic Imaging, Echocardiography, Echocardiography, Doppler, Fibrosis, Heart Valve Diseases, Heart Valve Prosthesis, Hemodynamics, Multidetector Computed Tomography, Risk Factors
< Back to Listings
