Myocardial infarction and coronary artery ventricular fistulas due to blunt chest trauma. HISTORY AND CLINICAL FINDINGS: An 18-year-old previously healthy, cigarette smoking man with no other risk factors for ischaemic heart disease, was admitted to hospital after being kicked in the chest by a horse. On arrival he complained about pain in the lower mediastinum. INVESTIGATIONS: The ECG showed sinus rhythm, right bundle branch block and convex bowed ST elevation in leads V1-V3. Sixty minutes after the incident the cardiac enzymes (creatinekinase-MB fraction, troponin I) were significantly raised. Despite an only slightly reduced left ventricular function documented by transthoracic echocardiography, SPECT-thallium scan showed large scintigraphic defects. Coronary heart disease was excluded by coronary angiography. Four small coronary-ventricular fistulas were identified. Laevocardiography showed a hypokinesia in the antero-septal region. DIAGNOSIS, TREATMENT AND COURSE: We assumed traumatic myocardial infarction of the anterior wall and rupture of multiple small coronary vessels, leading to coronary-ventricular fistulas. No interventional or surgical therapy was performed. Later on the left ventricular function became normal. Echocardiography merely outlined an akinetic scar in the middle of the septum. At exercise ECG test sixteen months later, the patient remained asymptomatic and was able to exercise without any signs of ischaemia up to a work load of 175 W. Furthermore, the fistulas could be seen by echocardiography. CONCLUSION: Cardiac involvement should be considered in all cases of blunt chest trauma. In addition to a traumatic myocardial infarction fistulas may also, though rarely, occur. Myocardial scintigraphy after cardiac contusion is not suitable for diagnosing myocardial ischaemia or vitability.