Dual Antiplatelet Therapy vs. Single Antiplatelet Therapy After Transcatheter Aortic Valve Replacement: An Updated Systematic Review and Meta-Analysis

"Very" Very Late Stent Thrombosis: A Detailed Look at Two Cases

Although percutaneous coronary intervention (PCI) has radically transformed the scope of treating coronary artery disease with stenting, stent thrombosis (STh) remains a feared complication. Very late STh, a rare complication after PCI, refers to STh occurring greater than one year after post-stent implantation. An even rarer phenomenon, "very" very late stent thrombosis (VVLST), is described in the literature as STh occurring more than five years post-stent implantation. To our knowledge, there are only 10 case reports and one case series describing VVLST. We discuss two additional complex clinical cases of VVLST presenting as ST-elevation myocardial infarction. We highlight epidemiology, pathophysiology, presentation, diagnostic methods, treatment approach, associated complications, and the need for more extensive future work to minimize the risk of VVLST.

Nondual Antiplatelet Therapy Versus Dual Antiplatelet Therapy Before Transcatheter Aortic Valve Replacement: A Systematic Review and Meta-analysis

ABSTRACT

Transcatheter aortic valve replacement (TAVR) is an interventional procedure performed in patients with severe aortic stenosis and often required perioperative antiplatelet therapy. Most previous studies have focused on antiplatelet therapy following TAVR. However, few studies have investigated the prognostic effect of preoperative antiplatelet therapy in patients undergoing TAVR. This study aimed to compare the efficacy and safety of nondual antiplatelet therapy (non-DAPT) and DAPT before TAVR. We performed a systematic search of Embase, PubMed, and Web of Science until February 2023. Studies were eligible if they compared non-DAPT (single antiplatelet therapy or no antiplatelet therapy) with DAPT in patients before TAVR. A total of 5 studies, including 2329 patients, met the inclusion criteria and were included in the meta-analysis. Preoperative non-DAPT significantly decreased minor bleeding events compared with preoperative DAPT [odds ratio 0.58; 95% confidence interval: 0.44-0.76]. There were no significant differences in the incidence of other bleeding events, transfusions, stroke, myocardial infarction, or all-cause death. Preoperative single antiplatelet therapy significantly decreased the incidence of major bleeding compared with DAPT (odds ratio 0.14; 95% confidence interval: 0.04-0.48). Preoperative non-DAPT significantly reduced minor bleeding events in patients undergoing TAVR, without increasing the risk of stroke and myocardial infarction.

Optimal antiplatelet and antithrombotic regimen post-transcatheter aortic valve replacement

BACKGROUND

There are limited data regarding optimal antiplatelet/antithrombotic therapy following transcatheter aortic valve replacement (TAVR).

METHODS

In this single-centre retrospective study including TAVR patients from 2012 to 2020, ischemic and bleeding outcomes were compared between antiplatelet (dual antiplatelet [DAPT] vs. single antiplatelet [SAPT]) and oral anticoagulation (OAC) groups using incidence rate, Kaplan-Meier and Cox proportional hazards analysis.

RESULTS

Total 492 patients (mean age 79.7 ± 7.7 years, 53.7% males, 83.5% Caucasian) were included. There was higher incidence of 1-year death or ischemia with DAPT vs. SAPT (23.6 vs. 14.8 per 100 patient-years [PY], incidence rate ratio [IRR] 1.60, 95% confidence interval [CI] 0.97-2.68, p = .05), especially in those without coronary artery disease (23.9 vs. 10.7 per 100 PY, IRR 2.24, 95% CI 1.10-4.47, p = .017). There was significantly higher major bleeding in those on OAC vs. no OAC (15 vs. 8 per 100 PY, IRR 1.87, 95% CI 1.10-3.11, p = .016), especially late (>1-year) bleeding (10.2 vs. 3.6 per 100 PY, IRR 2.81, 95% CI 1.33-5.92, p = .004). In multivariate analysis, DAPT was an independent predictor of death or ischemia (adjusted hazard ratio [aHR] 1.41, 95% CI 1.01-1.96, p = .041). OAC was an independent predictor of major bleeding (aHR 2.32, 95% CI 1.31-4.13, p = .004).

CONCLUSIONS

There is signal to harm with routine use of DAPT post-TAVR. There is higher incidence of late bleeding post-TAVR with OAC, suggesting potential role for alternate antithrombotic strategies.

The search for optimal antithrombotic therapy in transcatheter aortic valve implantation: facts and uncertainties

Transcatheter aortic valve implantation (TAVI) is a minimally invasive procedure, which is used frequently in patients with symptomatic severe aortic valve stenosis. Most patients undergoing TAVI are over 80 years of age with a high bleeding as well as thrombotic risk. Despite the increasing safety of the procedure, thromboembolic events [stroke, (subclinical) valve thrombosis] remain prevalent. As a consequence, antithrombotic prophylaxis is routinely used and only recently new data on the efficacy and safety of antithrombotic drugs has become available. On the other hand, these antithrombotic drugs increase bleeding in a population with unique aortic stenosis-related bleeding characteristics (such as acquired von Willebrand factor defect and angiodysplasia). In this review, we discuss the impact of thromboembolic and bleeding events, the current optimal antithrombotic therapy based on registries and recent randomized controlled trials, as well as try to give a practical guide how to treat these high-risk patients. Finally, we discuss knowledge gaps and future research needed to fill these gaps.