Acute myocardial infarction following allogeneic hematopoietic stem cell transplantation: A national cohort study.

Acute myocardial infarction (MI) is a relatively rare but life-threatening complication of allogeneic hematopoietic stem cell transplantation (allo-HSCT). Information regarding the clinical characteristics, outcomes, and prognostication of post-transplant MI is lacking. We conducted a nationally representative cohort study at 34 centers in China. Patients with MI were retrospectively identified among those who underwent allo-HSCT. The diagnosis and classification of MI were reviewed according to established guidelines. One hundred thirteen patients were analyzed, including 23 patients with T1MI, 87 patients with T2MI, and three patients with T3MI. Patients with T2MI had a significantly higher mortality rate. Thrombotic microangiopathy (TMA) frequently coexisted with T2MI and adversely affected the overall survival. Disease relapse or progression, a platelet count <20 × 109/L, active TMA at MI onset, and Killip class 3-4 were identified as independent risk factors for 2-month mortality. We divided these patients into a low-risk group (without risk factors), an intermediate-risk group (1-2 risk factors), and a high-risk group (3-4 risk factors). Significantly different 2-month mortality rates were observed across these groups (11.1 %, 59.3 %, and 100.0 %, respectively). Available angiographic imaging data and antiplatelet therapy after MI onset may be associated with improved outcome, but the survival benefits and optimized medication use in patients with post-transplant MI require further validation. These findings may facilitate refined monitoring and management strategies of MI in the post-transplant population.