Coronary Artery Calcification; A Predictor of Severity of Coronary Artery Disease, Based on 64- Slice Coronary Computed Tomography Angiography

Abstract

ORIGINAL PROF-3713 ABSTRACT… Background: Due to increased risk of CAD and cardiovascular events, prediction of severity and/ or complexity of coronary artery disease (CAD) are valuable. Previously association between severity of CAD and total coronary artery calcium (CAC) score was not demonstrated but now there are lot of studies which have proven this association but still association between total CAC score and complexity of CAD is not well established. Objective: This study was conducted: (1) To investigate the association between coronary artery calcium (CAC) score and CAD assessed by CCTA. (2) To find which one of the two, CAD severity or complexity, is better associated with total CAC score in symptomatic patients having significant CAD. Study Design: Observational cross sectional study. Place and Duration: The study was conducted at Shifa International Hospital Faisalabad from March 2013 to June 2016. Materials and Methods: Total 195 consecutive patients of both gender age ≥20 years who was referred for CT angiography to our hospital and who fulfill the inclusion and exclusion criteria was included in the study. Before enrollment in the study all patients gave informed consent. Before CT angiography total CAC score was obtained by non-enhanced CT scans. Demographic characteristics of all patients were obtained. Regarding risk factors for CAD, history of hypertension, diabetes mellitus, family H/O ischemic heart disease and hyperlipidemia was noted. In all patients before CT angiography, Lab. investigations including complete blood count, fasting blood sugar, fasting lipid profile, blood urea and serum creatinine levels were obtained. Calcium scores were quantified by the scoring algorithm proposed by Agatston et al. All lesions were added to calculate the total CAC score by the Agatston method. Calcium scores were divided into the following categories: 0, 1-100, 101-400, and ≥400. The degree of stenosis was classified into four categories: (1) no stenosis, (2) minimal or mild stenosis (≤50%), (3) moderate stenosis (50%-70%), and (4) severe stenosis (>70%). CAD was defined when lumen diameter reduction was greater than 50% (moderate or severe stenosis). Results: Total 195 patients were studied. 136 (69.7%) were male and 59 (30.3%) were female. Mean age of study population was 52.8±10.38 years. 81(41.54%) patients had H/O chest pain, 11(5.64%) had H/O shortness of breath and 96(49.23%) presented with chest tightness. 104(53.33%) patients were hypertensive, 71(36.41%) were diabetic, 67(34.35%) had increased cholesterol level. In 57 (29.2%) there was no coronary artery disease, 58(29.7%) had mild CAD, 32 (16.4%) had moderate and 48 (24.6%) had severe coronary artery disease on CT angiography. Single vessel was involved in 38(19.5%) patients, 20(10.3%) had two vessel disease and triple vessel disease was present in 22(11.3%) patients. 104(53.3%) patients had zero calcium score. 44(22.6%) had CAC score between 1-100, 37 (19%) had CAC score between 101-400 and more than 400 CAC score was documented in 10 (5.1%) ...