الفهرس 
Chapter (1): Anatomy Of Coronary ArteriesOnly 14 pages are availabe for public view
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Abstract
Coronary Artery Disease (CAD) is one of the main causes of disability and death all over the world. The standard reference for diagnosis of CAD is coronary catheter angiography. The greatest advantage of catheter angiography is its high spatial resolution and option of directly performing intervention, such as Balloon dilatation or coronary stenting. Only one third of all coronary catheter examinations in the United States were performed in conjunction with an interventional procedure (Percutaneous Transluminal Coronary Angioplasty – PTCA), however, whereas the rest were performed for mere diagnostic purposes. The scenario is similar in developing countries. Accordingly, a reliable, noninvasive tool for imaging of the coronary arteries and for early diagnosis of CAD is highly desirable. Imaging of the heart has always been technically challenging because of the heart’s continuous motion. CT imaging of the heart moved into the diagnostic realm by the introduction of multi detector row CT (MDCT) and development of ECG-Synchronized scanning and reconstruction techniques these modalities allow for faster volume coverage and higher spatial and temporal resolution. The introduction of MDCT especially has greatly benefited cardiovascular CT imaging application
This current study was conducted on 70 patients presented with chest pain to evaluate the role of MDCT in the assessment and diagnosis of the cause of this chest pain.
All patients were subjected to full history taking, thorough clinical examination and review of the laboratory investigations and of available previous imaging studies. Patients with heart rate >60 beat/min received β-blocker; 100 mg atenolol orally 1 hour before the scan. The
retrospective gating technique was used to synchronize data reconstruction with ECG signal. Best systolic and diastolic reconstructions were made in all patients at a slice thickness of 0.75 mm and a reconstruction increment of 0.4 mm. The reconstruction with fewest motion artefacts was chosen and used for further analysis.
All patients were scanned using a 64-MDCT scanners. Automatic tube current modulation and adaptive electrocardiography (ECG) pulsing was applied in all patients. The scan range was extended to the level of the subclavian arteries in patients with internal mammary artery grafts. 60 patients received A bolus of iodinated contrast material (Ultravist 370, Schering AG, Berlin, Germany), which varied between 80 and 100 ml depending on the expected scan time, was injected in an antecubital vein followed by a saline chaser (40 ml; flow rate 4.0 to 5.0 ml/s). The flow rate (4.0 to 5.0 ml/s) was adjusted to the scan range (presence of left internal mammary artery) and the expected scan time (pitch dependent). A bolus tracking technique was applied to synchronize the data acquisition with the arrival of contrast in the bypass grafts and native coronary arteries
The current study included 63 males and 7 females and their age ranged between 28 and 74 years old. The patients had different risk factors for coronary artery disease
In our study, MDCT angiography of the 60 patients revealed, 21 (34.78%) were normal, 13 (21.74%) had insignificant stenosis, 14 (23.91%) patients had single vessel disease, 7 (11%) patients had two vessel disease and 5 (8%) had three vessel disease. On DSA, 18 (39.13%) patients were normal, 9 (19.56%) had insignificant stenosis, 10 (21.74%) had single vessel disease, 5 (11%) had two vessel disease
and 4 (8%) patients had three vessel disease. This distribution shows that there is no significant difference between CT and DSA in diagnosing the number of vessels involved. The most common category among patients with significant stenosis was single vessel disease.
This study confirms that MSCT is a reliable and accurate technique for excluding patients suspected of CAD in comparison with conventional angiography, thereby reducing the need for invasive coronary angiography.