A rare coronary artery anomaly - type X dual left anterior descending artery: a case report with brief literature review

Abstract

Introduction: Type X dual left anterior descending artery (LAD), which is a rare subtype of coronary artery anomalies and newly defined in the literature, usually presents an asymptomatic clinical course and is detected incidentally in diagnostic angiography. However, in the presence of obstructive disease, myocardial revascularization may be required. It is critical to identify the presence of Type X dual LAD in order to prevent misdiagnoses in coronary angiography and to prevent complications during angioplasty or surgical myocardial revascularization. We present a case of rare type X dual LAD coronary anomaly presented with chest pain. Case presentation: A 66-year-old female patient was admitted to the hospital with the complaints of atypical chest pain and palpitations. Examinations revealed sinus tachycardia, mitral valve calcific degeneration, mild tricuspid valve insufficiency, and left atrial dilatation on echocardiography, hyperlipidemia and normal troponin I value. Coronary artery disease risk (according to the Framingham risk score) was low (8%), and coronary coronary computed tomography angiography (CCTA). The calcium score was calculated as 1782 Agatston. There were calcified atheroma plaques in the left main coronary artery (LMCA) ostium and distal section causing less than 25% stenosis. A well-developed diagonal branch of LAD was observed. The LAD calibration was thin and terminated at the proximal of anterior interventricular sulcus (AIVS). Therefore, it was evaluated as short LAD. A long LAD was detected, which was arising from the right coronary sinus with a separate ostium, reached the AIVS at the midventricular level after a pre-pulmonic course in front of the right ventricular outflow tract and extended to the apex. The long LAD was located in front of the right ventricle, close to the anterior chest wall. As there were no signs of myocardial ischemia or injury, calcified lesions in coronary arteries were nonstenotic (excluding thus acute coronary syndrome as cause of chest pain) the medical treatment with antilipidemia and hypertension and atherosclerosis modifying medications has been started and she was discharged with recommendations to continue treatment, modify risk factors for coronary artery disease and follow-up visits were scheduled. Conclusion: Our case demonstrated that rare dual type X LAD can be detected by CCTA in a patient evaluated for chest pain. CCTA is a useful tool for detection of coronary anomalies, that should be sought in patients with chest pain, absence of acute myocardial injury and low Framingham risk score.

Keywords

• coronary artery anomaly
• left anterior descending artery
• type x dual left anterior descending artery