Patterns of cardiac dysfunction after carbon monoxide poisoning

Objective: To describe the structural sequelae of carbon monoxide (CO) poisoning on the heart assessed using stress cardiac MRI (CMR). CO poisoning is common. While acute cardiac injury is frequent among survivors, the mid- and long-term effects of CO on the myocardium are unclear. Methods: CMR studies performed between the years 2005 and 2014 for a primary diagnosis of CO poisoning at a tertiary care center were reviewed by an experienced cardiologist. Variables of interest were compared between patients with normal and abnormal studies to identify factors associated with cardiac dysfunction. Results: Eighty-eight patients underwent stress CMR, age 34 years (range 11-70); 49% were male, 74 had acute poisoning and 14 had chronic poisoning (CO exposure for longer than 24 hours). Time from CO poisoning to imaging was 24 months (1day-120 months). Patients were stratified into four categories, which included those with acute poisoning imaged: • ≤12 months; • 12-60 months; • >60 months from the event; and • those with chronic poisoning. Overall, 26 studies (30%) were abnormal. The most common findings were: left ventricular systolic dysfunction in 14 patients, right ventricular systo