A Rare Coronary Artery Anomaly: Double Left Anterior Descending Artery
A 36-year-old male patient was admitted to our hospital with the complaint of non-specific chest pain. He had a history of smoking and hypertension, potential risk factors for coronary artery disease. Also his father at the age of 46 years had died suddenly with unclear etiology. At the time of the evaluation, the patient had been on antihypertensive therapy with beta blocker for 2 years. The chest pain was not typical for angina pectoris but the patient was very nervous due to his family history.\nThe physical examination did not reveal any abnormal findings. Blood pressure was 140/90 mmHg and pulse 72 beats/min. Cardiac and lung auscultation were normal. The electrocardiogram (ECG) and chest X-ray were normal. Routine blood and biochemical laboratory tests were within normal limits. Transthoracic echocardiograpic examination revealed normal left ventricular size and contractility. The left ventricular ejection fraction was 65%. For further evaluation an exercise test was required but this was not possible as the patient had recently undergone knee surgery for meniscopathy. Therefore, to evaluate chest pain and to detect or rule out coronary artery disease, the patient underwent computed tomography coronary angiography (CTCA). CTCA was performed using a 64 slice CT scanner (Siemens Sensation 64, Germany). Scan parameters were as follows: Slice collimation, 32 × 2 × 0.625 mm; rotation time, 0.33 mins; tube voltage, 120 kV; tube current, 600 mA; and pitch, 0.2. The average heart rate was 71 bpm during the scan. The scan time was 7 sec. CT angiography was triggered automatically by the arrival of the contrast bolus (automatic bolus tracking). A prescan was taken at the level of the aortic root and a region of interest (ROI) was placed on the ascending aorta. As soon as the signal density level in the ascending aorta reached the predefined threshold of 120 Hounsfield units (HU), the scan started. We injected 80 ml nonionic contrast medium (Iomeron 400/ml; Iomeprol, Bracco, Italy) at a flow rate of 5 ml/s in the left antecubital vein. This was followed by a 40 ml saline chaser bolus at a flow rate of 4 ml/s to wash out contrast from the right ventricle. During the scan, the ECG was recorded simultaneously. The reconstruction interval for the coronary arteries with the fewest motion artifacts was determined (images at 75% of the R-R interval) and used for further analysis. For reconstruction of axial images, we used a slice thickness of 0.75 mm and a slice width of 0.5 mm. A medium soft-tissue reconstruction kernel (B30f) was used for reconstruction. For post-processing, an external workstation (Leonardo, Siemens, Germany) was used. In addition to the transverse source images, multiplanar reformations (MPRs), curved MPR images, maximum intensity projections (MIPs), and volume rendered (VR) images were utilized for the evaluation. VR reconstructions depicted the vascular anatomy well and were used for 3-dimensional (3D) orientation.\nCoronary CTA demonstrated an anomalous left anterior descending artery (LAD) arising from the same ostium with the right coronary artery, which coursed downwardly along the interventricular sulcus, and another LAD arising from the left main coronary artery, which spread to the anterior wall of the left ventricle toward the left ventricular apex [Figures and ]. The right coronary artery (RCA) and the left circumflex artery (LCX) were normal. There were no significant coronary stenoses or occlusions. However, the anomalous LAD was coursing between right ventricular outflow tract and aorta which should be considered to be critical because of the potential to provoke myocardial ischemia or even sudden cardiac death []. These CTCA findings were consistent with double LAD, with one vessel arising from the ostium of right coronary artery and the second one arising from the left main coronary artery. The patient was informed about the anomaly and the potential complications. He did not want to undergo a surgical revascularization. He is now on follow up with no signs of myocardial ischemia.