The largest study to date to systematically review outcomes associated with leaflet thrombosis after transcatheter aortic valve implantation (TAVI) indicates that the presence of leaflet thrombosis does not predict all-cause mortality, stroke, or transient ischaemic attack at 406 days.
Writing in JACC: Cardiovascular Interventions, Philipp Ruile (Department of Cardiology & Angiology II, University Heart Center Freiburg-Bad Krozingen, Bad Brozingen, Germany) report that the presence of leaflet thrombosis is associated with an increased rate of transient ischaemic attack but appears to have no influence of the rate of stroke or mortality. “The purpose of the present was to investigate medium-term outcomes in patients with leaflet thrombosis from a large single-centre cohort,” the authors add.
Reviewing data for patients who were assessed with computed tomography (CT) angiography after undergoing TAVI at their centre, Ruile et al found 15.9% of patients (120 of 754) had evidence of leaflet thrombosis. The overall mortality rate at 406 days was 11.1% and did not differ between patients with leaflet thrombosis and those without. The Kaplan-Meier 18-month estimate for survival also showed similar survival rates for patients with leaflet thrombosis vs. those without.
There were no significant differences between groups in terms of the rate of stroke or the rate of transient ischaemic attack. Ruile et al observe that the reason why their study did not find a link between leaflet thrombosis and transient ischaemic attack—in contrast to a previous study—may relate to “high variability in the incidence of transient ischaemic attack depending on whether symptoms were self-reported or the result of a neurological evaluation of a whole cohort”. They add that a study that provides a systematic analysis of patients with leaflet thrombosis regarding neurological symptoms is “currently missing but urgently needed considering the competing risks for stroke in a population with a high prevalence (approximately 40%) of atrial fibrillation”.
Leaflet thrombosis was not found to be an independent predictor of all-cause mortality in either a univariate analysis or in a multivariate analysis. It was also not found to be a predictor of stroke or transient ischaemic attack in a univariate analysis. According to Ruille et al, the overall incidence of stroke/transient ischaemic attack was too low in their cohort to perform a “meaningful multivariate analysis”.
Ruile told Cardiovascular News: “Based on our study we conclude that leaflet thrombosis is not associated with an increased risk for mortality or stroke for the medium-term. But still there remain concerns about subsequent haemodynamic valve deterioration.”