Cooper, Leslie

Abstract Introduction Cannabidiol has been shown to exert significant anti-inflammatory effects and has demonstrated efficacy in murine models of autoimmune myocarditis, pericarditis, and heart failure. The ARCHER Study assessed whether a pharmaceutically produced cannabidiol formulation showed beneficial effects on cardiac magnetic resonance (CMR) endpoints known to predict prognosis in this patient population. Methods In a multicentre international double-blind placebo-controlled phase 2 study, we randomly assigned 109 patients within 10 days of CMR confirmed diagnosis of acute myocarditis to 12 weeks of pharmaceutically produced oral cannabidiol (active) or placebo. Dose was titrated up to 10 mg/kg of body weight twice daily. Primary endpoints were the difference in extracellular volume (ECV) and global longitudinal strain (GLS) measured by CMR at week 12. Other CMR endpoints included left-ventricular ejection fraction (LVEF), LV mass, intracellular volume (ICV), LV end-diastolic and end-systolic volumes (LVEDV, LVESV), and left-atrial end-systolic volume (LAESV). Results All randomized patients (56 active/53 placebo) completed the study with no loss to follow-up. Study drug appeared safe and well tolerated. Baseline mean ECV 38.9 ± 10.9 ml, GLS −15.3 ± 3.6%, and LVEF 60.6 ± 9.9% were consistent with mild to moderate myocarditis and predominantly intact LV function. Week 12 mean ECV was 33.6 ml in the active group and 37.3 ml in the placebo group, a difference of −3.7 ml, confidence interval (CI): −7.4 to 0.1; P = .0538; GLS was −16.0% in the active group and −15.9% in the placebo group, difference of −0.1, CI: −1.2 to 1.1; P = .90. Left ventricular mass was significantly reduced in the active group at 121.1 g compared to placebo 130.3 g, a difference of −9.2, CI: −16.4 to −2.1; P = .0117. In terms of remodelling, LAESV was significantly reduced in the active group (−8.1 ml; P = .0376) while the reduction in LVEDV failed to reach significance (−7.4 ml; P = .098). Conclusion In mild-to-moderate acute myocarditis, treatment with pharmaceutically manufactured cannabidiol was not associated with a statistically significant change in myocardial ECV or GLS, although a trend towards reduction in ECV was observed. In addition, improvement in other potential markers of myocardial recovery, including a significant reduction in LV mass, was seen in the active treatment group. Further investigation of the therapeutic potential of this therapy in inflammatory cardiac conditions is warranted.

Introduction: IL2 soluble receptor (IL2Rs) and neopterin (NPT) are peripheral markers of T cell and monocyte activation investigated extensively in auto-immune disorders. We assessed these biomarkers in subjects with non ischemic cardiomyopathy of recent onset (ROCM) from the IMAC2 (Intervention in Myocarditis and Acute Cardiomyopathy) registry. We compared the degree of cellular activation in peripartum cardiomyopathy (PPCM) with that evident in non-peripartum women and men with ROCM. Methods: 130 subjects were investigated: 96 subjects with ROCM including 37 women with PPCM (group 3), 27 non-peripartum women (group 2) and 32 men (group 1), and 34 controls without cardiac disease (CTL). All subjects with ROCM had serum obtained at entry and an assessment of LVEF by transthoracic echocardiography. LVEF was reassessed 6 months after enrollment. Results: The ROCM cohort (n=96, 64F/32M, mean age 30±6) had a mean LVEF at baseline of 0.24±0.08 which increased to 0.43±0.13 at 6 months. For controls (mean age 45±6, 24F/10M) the mean LVEF was 0.58±0.10. Both IL2Rs and NPT were markedly elevated in ROCM subjects compared to controls (IL2Rs: ROCM=1411±671, CTL=970±329 pg/ml, p<0.001; NPT: ROCM=9.2±5.6, CTL=6.2±3.1 nmol/l, p=0.003). Increased NYHA class was associated with higher serum levels for both NPT (p=0.013) and IL2Rs (p=0.009). No differences were evident in subjects with PPCM versus men and women with ROCM for either IL2Rs (group 1/2/3 =1524±504/1531±904/1225±566 pg/ml, p=0.10) or NPT (group 1/2/3=9.4±6.5 /9.3±5.8 /8.9±4.7 nmol/l, p=0.92). IL2Rs levels were lower in black subjects: blacks (n=25) IL2Rs=1123±496; whites (n=71) 1513±698, p=0.012. Levels of IL2Rs and NPT did not predict the degree of recovery at 6 months, although there was a nonsignificant trend towards more recovery with lower IL2Rs levels. Conclusions: Marked elevation of IL2Rs and NPT, biomarkers of cellular immune activation, are evident in subjects with ROMC. The degree of activation in subjects with PPCM appears similar to that seen in men and non-peripartum women with ROCM, suggesting similar inflammatory pathogenesis for these syndromes of acute heart failure. The relationship of cellular activation to myocardial injury and recovery in ROCM should be further investigated.