Prognostic impact of serum type IV collagen 7S after transcatheter aortic valve implantation

Outcomes after transcatheter aortic valve implantation (TAVI) remain variable, and the impact of extracardiac dysfunction prior to the procedure has not been fully elucidated. Type IV collagen 7S (P4NP 7S) is a serum marker originally established in hepatic fibrosis and has been reported to reflect venous congestion and cardio-hepatic interaction in cardiovascular disease. We investigated whether preprocedural P4NP 7S predicts clinical outcomes following TAVI. This single-center prospective cohort comprised 398 consecutive patients with severe aortic stenosis who underwent TAVI between June 2019 and December 2024. Serum P4NP 7S levels were measured prior to the procedure, and patients were stratified into tertiles. The primary endpoint was a composite of all-cause death or heart failure (HF) hospitalization. During a median follow-up of 773 days, 82 primary events occurred. Higher tertiles of P4NP 7S were associated with congestion-related clinical profiles, and event rates increased progressively across tertiles (log-rank P < 0.001). In multivariable Cox proportional hazards models adjusting for potential confounders, elevated P4NP 7S remained independently associated with adverse outcomes (middle vs. lower tertile: hazard ratio [HR] 2.30, 95% confidence interval [CI] 1.15-4.61; upper vs. lower tertile: HR 2.90, 95% CI 1.48-5.65). When analyzed as a continuous variable, each 1-ng/mL increase in P4NP 7S was associated with a higher risk (HR 1.15, 95% CI 1.06-1.26). Preprocedural serum P4NP 7S independently predicted all-cause death or HF hospitalization after TAVI. Measurement of P4NP 7S may aid risk stratification and help identify patients who warrant closer post-TAVI follow-up.