Familial Spontaneous Coronary Artery Dissection Involving the Left Main Coronary Artery in a Young Male: A Case Report.

Spontaneous coronary artery dissection (SCAD) is a rare but important cause of acute coronary syndrome, particularly in young patients without conventional risk factors. While often sporadic, familial clustering has been increasingly recognized, indicating a genetic predisposition. We report a case of a 33-year-old male presenting with acute chest pain and ST-segment elevation. Coronary angiography showed spontaneous dissection with a large thrombus burden involving the distal left main coronary artery and extending into the proximal left anterior descending artery and circumflex artery. The patient had a family history of SCAD involving 2 siblings. Given the high thrombus burden and risk of procedural complications, a conservative approach was chosen. Management included tirofiban infusion, dual antiplatelet therapy, and anticoagulation. Intravascular ultrasound confirmed thrombus and intramural hematoma. Follow-up showed near-complete healing. Genetic testing identified a heterozygous TTN gene variant in the patient and his brother, a gene associated with cardiomyopathies. In conclusion, this case emphasizes the potential familial nature of SCAD and suggests a possible, previously unrecognized, association between TTN gene mutations and coronary dissection, indicating that conservative management with antiplatelet and anticoagulant therapy may be effective even in complex SCAD cases with high thrombus burden.