Association between subclinical haemolysis and periprocedural outcomes in patients undergoing transcatheter aortic...

Transcatheter aortic valve implantation (TAVI) has become a cornerstone treatment for patients with severe aortic stenosis, especially those unsuitable for surgery. Intravascular haemolysis has been described in patients with aortic stenosis. This study aimed to assess the prevalence of haemolysis in patients with severe AS undergoing TAVI and its association with immediate and 30-day post-procedural outcomes.

The HEMO-TAVI study was a prospective, single-centre cohort study conducted at University Hospital Reina Sofía (Córdoba, Spain) from June 2020 to September 2023. Consecutive patients scheduled for TAVI were enrolled. Haemolysis was defined as LDH>220U/L plus ≥2 criteria (low haemoglobin, low haptoglobin, elevated reticulocytes, or schistocytes). The primary endpoint was a composite of peri-procedural and 30-day adverse events.

Among 301 patients, pre-procedural haemolysis was identified in 18 (6.0%). Patients with haemolysis had higher interventricular septum thickness and transvalvular gradients. The composite endpoint occurred more frequently in the haemolysis group (44.4% vs 21.2%, OR_adj 2.23, 95% CI 1.12-8.25, p=0.025). Haemolysis was independently associated with a greater number of complications (OR_adj 3.26, 95% CI 1.19-8.47, p=0.016).

Pre-procedural haemolysis might be present in TAVI candidates and is associated with increased peri-procedural and 30-day complications. Pre-procedural haemolysis may serve as a marker of elevated procedural risk.