Aortic valve calcification and endomyocardial fibrosis determine adverse outcomes following transcatheter aortic valve replacement

Abstract

Funding Acknowledgements Type of funding sources: None. Aims There is evidence to suggest that subtype of aortic stenosis (AS), degree of myocardial fibrosis (MF) and level of aortic valve calcification (AVC) are associated with adverse cardiac outcome in AS. Since little is known about their respective contribution, we sought to investigate their relative importance and interplay as well as association with adverse cardiac events. Methods 100 consecutive patients with severe AS and indication for transfemoral transcatheter aortic valve replacement (TAVR) were prospectively enrolled between January 2017 and October 2018. Patients underwent transthoracic echocardiography, multi detector computed tomography (MDCT) and left ventricular endomyocardial biopsy at the time of TAVR. Results The final study cohort consisted of 92 patients with completed study protocol comprising of 39 (42.4 %) normal ejection fraction high gradient (NEFHG), 13 (14.1 %) low EF high gradient (LEFHG), 25 (27.2 %) low EF (flow) low gradient (LEFLG) and 15 (16.3 %) paradoxical low flow low gradient (PLFLG) AS. The high gradient phenotypes (NEFHG and LEFHG) showed the largest amount of AVC (807 ± 421; 813 ± 281 mm³ respectively) as compared to the low gradient phenotypes (LEFLG and PLFLG; 503 ± 326; 555 ± 594 mm³ respectively, p < 0.05). Conversely, MF was most prevalent in low output phenotypes (LEFLG > LEFHG > PLFLG > HEFHG, p < 0.05). This was paralleled by larger cardiovascular mortality within 600 days post TAVR (LEFLG n = 7 > PLFLG n = 4 > LEFHG n = 2 > NEFHG n = 1). In Patients with high MF burden a higher AVC was associated with a lower mortality (p = 0.045, HR = 0.261, 95%CI 0.07-0.97). Within LEFLG AS, patients with larger AVC (>476.8 mm³) had larger MF (40.2%) and higher cardiovascular mortality (n = 5) as compared to patients with lower AVC (£476.8 mm³, 17.1% MF, p = 0.027, cardiovascular mortality n = 2). Conclusion MF is associated with adverse cardiovascular outcome following TAVR which is most prevalent in low ejection fraction situations. In the presence of large MF burden patients with large AVC have better outcome following TAVR. Conversely worse outcome in large MF and relatively little AVC may be explained by a relative prominence of an underlying cardiomyopathy while better survival rates in large AVC patients may indicate severe AS associated pressure overload relief and subsequently improved survival following TAVR.

Editors' highlight picks from 2023 in ESC heart failure

“…21 Reports published in ESC Heart Failure during 2023 confirmed that myocardial fibrosis 22 and LVH 23 were associated with adverse outcomes after TAVI, and also added novel important pieces of information. First, that the degree of aortic valve calcification was inversely associated with post-TAVI mortality in subjects with high myocardial fibrosis 22 suggests prominence of an underlying cardiomyopathy. Second, the reversed LVH after TAVI was accompanied by an increased scintigraphic heart-to-mediastinum (H/M) ratio, 23 suggesting a link between LVH and sympathetic dysfunction in AS and their reversibility after TAVI.…”

“…Transcatheter aortic valve implantation (TAVI) has been reported to lead to improved cardiac function, but HF readmission is still a clinical problem 21 . Reports published in ESC Heart Failure during 2023 confirmed that myocardial fibrosis 22 and LVH 23 were associated with adverse outcomes after TAVI, and also added novel important pieces of information. First, that the degree of aortic valve calcification was inversely associated with post‐TAVI mortality in subjects with high myocardial fibrosis 22 suggests prominence of an underlying cardiomyopathy.…”