Cardiovascular Abnormalities in Carbon Monoxide Poisoning

Acute carbon monoxide (CO) poisoning is the most common cause of poisoning and poisoning-related death in the United States. It manifests as broad spectrum of symptoms ranging from mild headache, nausea, and fatigue to dizziness, syncope, coma, seizures resulting in cardiovascular collapse, respiratory failure, and death. Cardiovascular complications of CO poisoning has been well reported and include myocardial stunning, left ventricular dysfunction, pulmonary edema, and arrhythmias. Acute myocardial ischemia has also been reported from increased thrombogenicity due to CO poisoning. Myocardial toxicity from CO exposure is associated with increased short-term and long-term mortality. Carboxyhemoglobin (COHb) levels do not correlate well with the clinical severity of CO poisoning. Supplemental oxygen remains the cornerstone of therapy for CO poisoning. Hyperbaric oxygen therapy increases CO elimination and has been used with wide variability in patients with evidence of neurological and myocardial injury from CO poisoning, but its benefit in limiting or reversing cardiac injury is unknown. We present a comprehensive review of literature on cardiovascular manifestations of CO poisoning and propose a diagnostic algorithm for managing patients with CO poisoning.