Myocardial injury during transfemoral transcatheter aortic valve implantation: an intracoronary Doppler and cardiac magnetic resonance imaging study

Aims: Myocardial injury reflected by a post-procedural increase of serum troponin I (TnI) occurs frequently during transcatheter aortic valve implantation (TAVI). It is potentially caused by intraprocedural hypotension, periprocedural coronary microembolisation and post-procedural (para)valvular leakages (PVLs). We invasively assessed coronary flow dynamics including coronary flow velocity reserve (CFVR), embolic high intensity transient signals (HITS) as well as rapid pacing induced hypotension and post-procedural PVLs to determine their contribution to post-procedural TnI increases. Methods and results: In 15 transfemoral TAVI patients, TnI was measured serially, and cardiac MRIs with late gadolinium enhancement (LGE) were performed pre- and post-interventionally. There were no significant correlations between coronary flow dynamics, CFVR and the area under the curve (AUC) of TnI over 72 hours. Despite the detection of HITS in all patients and during all procedural steps, there was also no correlation between the amount of HITS and the AUC of TnI. However, there were positive correlations between the duration of rapid pacing as well as the time of subsequent blood pressure recovery and the AUC of TnI. Both LGE and more than mild PVL were observed in a single case only. Conclusions: Myocardial injury after TAVI appears to be related more to hypoperfusion-induced ischaemia than to periprocedural microembolisation.