Abstract
OBJECTIVES: Lymphocytes are key players in the adaptive immune system, playing an important role in the anti-inflammatory balance in the post-myocardial infarction (MI) period and being involved in healing process. We aimed to investigate temporal changes in lymphocyte subunits in maladaptive remodeling following acute myocardial infarction. DESIGN AND SETTING: A total of 84 patients with anterior ST-segment elevation MI (STEMI) were enrolled. Lymphocyte subunits were measured 1 day, 2 and 6 weeks after MI. Maladaptive cardiac remodeling was defined as an increase in left ventricular end-diastolic volume by ≥12% in cardiac magnetic resonance imaging at the 6-months follow-up. PARTICIPANTS: A total of 84 patients with anterior STEMI were enrolled. MEASUREMENTS AND RESULTS: On the first day post-MI, the median number of total lymphocytes, T cells, and B cells were higher in the maladaptive remodeling group than in the without maladaptive remodeling group. Two weeks post-MI, the median number of B cells was higher in the maladaptive remodeling group, but similar at 6 weeks post-MI. Regression analysis revealed that a high number of B cells on the first day post-MI was related to maladaptive remodeling. CONCLUSIONS: In the maladaptive remodeling group, both inflammation markers, T and B lymphocyte levels were higher in the initial phase of MI, while B cells were approximately two-fold higher and an independent predictor of maladaptive remodeling. This study strongly supports the idea of developing immunotherapies or treatments that target B cells in cardiac remodeling.