A coronary event without coronary artery disease: the hidden role of inherited thrombophilia—a case report

Background: ST-segment elevation myocardial infarction (STEMI) in young patients without traditional cardiovascular risk factors requires evaluation beyond atherosclerotic disease. Inherited thrombophilia and cancer-related prothrombotic states represent important alternative aetiologies. Case summary: A 42-year-old man presented with an acute inferior STEMI. Coronary angiography demonstrated thrombotic occlusion of the proximal right coronary artery, treated with drug-eluting stent implantation. The patient had no cardiovascular risk factors. His medical history was significant for seminomatous testicular cancer treated with orchiectomy and cisplatin-based chemotherapy 10 months prior. Laboratory and imaging findings did not support atherosclerotic disease, and tumour markers were within normal limits. Given the absence of conventional risk factors, further evaluation was undertaken. Genetic testing revealed inherited thrombophilia. Following multidisciplinary consultation, antithrombotic therapy was optimized by adding rivaroxaban and adjusting antiplatelet therapy. At 1-year follow-up, the patient remained asymptomatic with no recurrent thrombotic events. Discussion: This case highlights the importance of a systematic and personalized diagnostic approach in young STEMI patients without evident coronary artery disease. Although inherited thrombophilia was considered a plausible underlying cause of coronary thrombosis in this case, the coexistence of prior malignancy and cisplatin-based chemotherapy may have further amplified the patient's prothrombotic state. Therefore, it is probable that multiple pathogenic mechanisms coexisted and contributed to the development of coronary thrombosis. While typically linked to venous thromboembolism, inherited thrombophilia may also contribute to arterial thrombosis in selected patients, with important implications for long-term management.