Reduced hematopoietic-inflammatory response and worse outcomes in patients with recurrent myocardial infarction in comparison with primary myocardial infarction

Abstract

Background: Recurrent myocardial infarction (RMI) portends an unfavorable outcome, which might be related to diminished hematopoietic-inflammatory activation. We aimed to investigate the hematopoietic-inflammatory activation and the outcome in categorized patients with primary myocardial infarction (PMI) versus RMI as well as chronic stable angina (CSA) by ¹⁸F-FDG PET.

Results: A total of 105 patients (88 males; 60.1 ± 9.7 years) were included. Target-to-background ratio of bone marrow (TBR_BM) was highest in the PMI group (n = 45), intermediate in the RMI group (n = 30), and lowest in the CSA group (n = 30) (P < 0.001). RMI group exhibited larger scar, significantly reduced left ventricular ejection fraction, and enlarged end systolic volume in comparison with the PMI and CSA groups, respectively (P < 0.05). Additionally, there was a significantly positive correlation between TBR_BM and TBR_aorta (P < 0.001). The cumulative major adverse cardiac events free survival of patients in the RMI group was lower than that in the PMI and CSA groups during a median follow-up of 16.6 months (P = 0.026).

Conclusions: RMI conferred relatively decreased hematopoietic-inflammatory activation compared with PMI. Patients with RMI presented subsequent enlarged myocardial scar, worsened cardiac dysfunction, aggravated remodeling, and worse outcomes than that in PMI patients.

Keywords: Bone marrow; Hematopoiesis; Positron emission tomography; Recurrent myocardial infarction.

Fig. 1

BM, Splenic, and aortic ¹⁸F-FDG activity among the three groups. The ¹⁸F-FDG activity of BM (a) and aorta (c) was highest in the PMI group, intermediate in the RMI group, and lowest in the CSA group. The splenic (b) ¹⁸F-FDG activity did not differ significantly among the three groups. TPD (%, d), Scar (%, e), HM (%, f), LVEF (%, g), EDV (mL, h), and ESV (mL, i) among the three groups. BM, bone marrow; CSA, chronic stable angina; EDV, end-diastolic volume; ESV, end-systolic volume; HM, hibernating myocardium; LVEF, left ventricular ejection fraction; PMI, primary myocardial infarction; RMI, recurrent myocardial infarction; TPD, total perfusion deficit. *P < 0.05. **P < 0.01. ***P < 0.005. ns, no significance

Fig. 2

Correlations of BM, aortic and splenic ¹⁸F-FDG activity. There was a significantly positive correlation between BM and aortic ¹⁸F-FDG activity (a); There was no correlation between BM and splenic ¹⁸F-FDG activity in the overall study population (b). BM, bone marrow

Fig. 3

Representative examples of BM, spleen and aorta. BM, Splenic, and aortic ¹⁸F-FDG activity among the three groups. The coronal fusion of BM, axial fusion of spleen and aorta. BM, bone marrow

Fig. 4

Kaplan–Meier for MACE-free survival curve among the three groups. The cumulative MACE-free survival of patients in the RMI group was significantly lower than that in the PMI and CSA groups. CSA, chronic stable angina; MACE, major adverse cardiac events; PMI, primary myocardial infarction; RMI, recurrent myocardial infarction