Right coronary anomaly in a patient with myocarditis and cardiac arrest: a case report

Management of coronary anomalies continues to be a controversial topic in medicine, for which only in specific clinical scenarios recommendations for management are clearly defined. We are presenting a previously healthy 18-year-old patient who survived sudden cardiac death (SCD). Multiple potential aetiologies were evaluated, including malignant coronary anomaly, acute myocarditis, potential Brugada type 3 electrocardiographic pattern, and urine drug screening positive for lysergic acid diethylamide (LSD).

Malignant right coronary anomaly with interarterial course and acute angle takeoff was diagnosed with coronary computed tomography angiography. Signs of acute myocarditis were detected in cardiac magnetic resonance imaging and endomyocardial biopsy. Due to potential Brugada type 3 electrocardiographic pattern flecainide provocation testing was performed to rule out Brugada Syndrome. Confirmatory chromatography revealed that prior LSD drug screening was false positive. Ultimately, the patient underwent cardiothoracic surgery with unroofing of the right coronary artery. Subsequent clinical course was favourable.

Right coronary artery anomalies are more prevalent than left coronary anomalies but less often associated with SCD. Interarterial course and acute angle takeoff are risk factors for unfavourable outcomes. Myocarditis is a potential trigger of arrhythmias and SCD. In patients with Brugada type 2 and 3 electrocardiographic pattern (saddleback ST-segment elevation), provocation testing with flecainide, ajmalin, or procainamide can be used to unmask Brugada type 1 electrocardiographic pattern. Due to the proarrythmic potential of many recreational drugs, screening for these substances can be useful in young adults presenting after cardiac arrest; cross-reaction of substances as in our patient have to be considered.