Diagnostic usefulness and limitation of cardiac magnetic resonance for identifying myocardial damage in survivors of cardiac arrest in midtown.

Background: Cardiac magnetic resonance (CMR) has been reported to identify myocardial damage inducing out-of-hospital cardiac arrest (OHCA). However, the usefulness of CMR may be affected by the medical institutions, patients' ages, and myocardial diseases.

Aim: To clarify the clinical usefulness and limitation of CMR for identifying myocardial damage in the survivors of OHCA in midtown.

Methods: Nineteen patients underwent CMR to detect myocardial damage related to OHCA in the midtown of a capital city. Cine, T1 and T2 mapping, T2-weighted, and late gadolinium enhancement (LGE) imaging were acquired using a 1.5 T scanner. We described the clinical characteristics of the survivors of OHCA and evaluated usefulness of CMR for identifying myocardial damage related to OHCA.

Results: Among 19 patients experiencing OHCA, 7 experienced it in trains or on railway platforms, 4 while practicing sports, and 4 during their daily work. Ten of the 19 survivors were diagnosed with coronary vasospasm (CVS), in whom CMR failed to depict its characteristic findings. CMR was useful for identifying myocardial damage associated with hypertrophic cardiomyopathy (HCM) or myocardial infarction (MI). LGE was related to serious ventricular arrhythmias after implantable cardioverter defibrillator (ICD) installation in 3 patients (CVS, 2; HCM, 1).

Conclusion: CMR is useful for identifying myocardial damage of HCM or MI inducing OHCA and predicting ventricular arrhythmias after ICD implantation but has limited capability for detecting myocardial damage of CVS.