METHODS AND RESULTS: Prospective multicentre study of consecutive patients with clinically suspected myocarditis who underwent blood testing for hs-cTnT, CMR and EMB as a part of diagnostic work-up. EMB was considered positive based on immunohistological criteria in line with the ESC definitions. CMR diagnoses employed tissue mapping using sequence-specific cut-off for native T1 and T2 mapping; active inflammation was defined as T1≥2SD and T2≥2SD above the mean of normal range. Hs-cTnT of greater than 13.9ng/1 was considered significant. A total of 114 patients (age (mean±SD) 54±16, 65% males) were included, of which 79(69%) had positive EMB-criteria, 64(56%) CMR criteria, and a total of 58 (51%) positive troponin. Agreement between EMB and CMR diagnostic criteria was poor (CMR vs. ESC: AUCs: 0.51 (0.39-0.62)). The agreement between the significant hs-cTnT rise and CMR-based diagnosis of myocarditis was good (AUC: 0.84 (0.68-0.92); p<0.001), but poor for EMB (0.50 (0.40-0.61). Hs-cTnT was significantly associated with native T1 and T2, hs-CRP and NT-pro BNP (r=0.37, r=0.35, r=0.30, r=0.25 p<0.001), but not immunohistochemical criteria or viral presence.
CONCLUSIONS: In clinically suspected viral myocarditis, all diagnostic approaches reflect the pathophysiological elements of myocardial inflammation, however the differing underlying drivers only partially overlap. The EMB and CMR diagnostic algorithms are neither interchangeable in terms of interpretation of myocardial inflammation nor in their relationship with myocardial injury.
BACKGROUND: PLWH have a higher prevalence of cardiovascular disease and heart failure (HF) compared with the noninfected population. The pathophysiological drivers of myocardial dysfunction and worse cardiovascular outcome in HIV remain poorly understood.
METHODS: This prospective observational longitudinal study included consecutive PLWH on long-term HAART undergoing cardiac magnetic resonance (CMR) examination for assessment of myocardial volumes and function, T1 and T2 mapping, perfusion, and scar. Time-to-event analysis was performed from the index CMR examination to the first single event per patient. The primary endpoint was an adjudicated adverse cardiovascular event (cardiovascular mortality, nonfatal acute coronary syndrome, an appropriate device discharge, or a documented HF hospitalization).
RESULTS: A total of 156 participants (62% male; age [median, interquartile range]: 50 years [42 to 57 years]) were included. During a median follow-up of 13 months (9 to 19 months), 24 events were observed (4 HF deaths, 1 sudden cardiac death, 2 nonfatal acute myocardial infarction, 1 appropriate device discharge, and 16 HF hospitalizations). Patients with events had higher native T1 (median [interquartile range]: 1,149 ms [1,115 to 1,163 ms] vs. 1,110 ms [1,075 to 1,138 ms]); native T2 (40 ms [38 to 41 ms] vs. 37 ms [36 to 39 ms]); left ventricular (LV) mass index (65 g/m2 [49 to 77 g/m2] vs. 57 g/m2 [49 to 64 g/m2]), and N-terminal pro-B-type natriuretic peptide (109 pg/l [25 to 337 pg/l] vs. 48 pg/l [23 to 82 pg/l]) (all p