Abstract
Introduction Acute myocardial infarction (MI) is a rare but life-threatening complication following allogeneic hematopoietic stem cell transplantation (allo-HSCT). Although several transplant-related conditions are recognized as cardiovascular risk factors, whether and how these factors are associated with the occurrence of post-transplant acute MI (PT-MI) remain unclear. The management of MI among transplant recipients is challenging given the frequent occurrence of anemia and increased bleeding risk, and prognostic information in this population is limited. We conducted a multicenter cohort study to investigate the clinical manifestations, causes, and outcomes in patients with PT-MI.
Methods Patients who developed acute MI after transplantation were retrospectively identified among those receiving allo-HSCT between April 2015 and March 2025 from 43 centers in China. The diagnosis and classification of MI were reviewed according to the 4th universal definition. Potential causes of type 2 MI (T2MI) were classified according to the 2020 ESC Guidelines. Categorical variables were compared using the Fisher’s exact test. Continuous variables were compared using the Mann-Whitney U test and were dichotomized according to cutoff values with the optimal Youden index if applicable. Candidate predictors for 2-month mortality after PT-MI (a univariate logistic p value of <0.1) were included in the multivariate analysis using a forward stepwise logistic regression model. Variables remaining in the final model with a p value of <0.05 were determined to be independent prognostic risk factors. The study protocol was approved by the central institutional review board of Peking University People's Hospital.
Results One hundred thirteen (113) patients with PT-MI were identified, including 23 (20.4%) with type 1 MI (T1MI), 87 (77.0%) with T2MI, and three (2.7%) with type 3 MI. Patients developed PT-MI at a median age of 52.5 (IQR, 40.75-60) years, and 84 of them were male. The median time of onset was significantly shorter for patients with T2MI than for those with T1MI (121 vs. 425 days after HSCT, p = 0.005). Patients with T2MI had a significantly higher mortality rate than those with T1MI (73.6% vs. 24.8%, p = 0.001). The most frequently reported potential causes of T2MI included anemia (93.1%), sepsis (29.9%), and hypoxemia (29.9%). Concomitant thrombotic microangiopathy (TMA) was frequently observed in patients with T2MI (49.4%). In these patients, MI was among the early end-organ manifestations of TMA (median time of onset: three days after TMA diagnosis for MI, one day for acute kidney injury, 3.5 days for CNS involvement, one day for gastrointestinal bleeding, and five days for polyserositis). Patients complicated with TMA showed poor overall survival (log rank p < 0.001).
Among patients with T1MI and T2MI, 62 (56.4%) died within two months of MI onset. Disease relapse or progression (p = 0.004), a platelet count of < 20×109/L (p = 0.019), active TMA at MI onset (p = 0.016), and Killip class 3-4 (p < 0.001) were identified as independent risk factors for 2-month mortality. We divided these patients into a low-risk group (without risk factors, n = 27), an intermediate-risk group (1-2 risk factors, n = 59), and a high-risk group (3-4 risk factors, n = 24). Significantly different 2-month mortality rates were observed across the three risk groups (11.1%, 59.3%, and 100.0%, respectively). The median survival was also well separated between patients in the intermediate-risk group and those in the high-risk group (29 vs. 3 days, respectively).
ConclusionsPT-MI is rare but potentially fatal. Compared with T1MI, T2MI is more common and has significantly worse outcomes. TMA is frequently complicated with T2MI and adversely affects the overall survival. Prognostic risk factors were identified, and a preliminary prognostication was explored for patients with PT-MI.
