Inclusion Criteria:  Subjects with suspected CAD who are referred for elective coronary angiography and/or interventions  Exclusion Criteria:  Patients with a history of cardiomyopathy and myocardial infarction (MI), left ventricular hypertrophy (LVH), pathological Q wave on ECG, typical left bundle block or right bundle block, incomplete right bundle block, or paced rhythm on ECG. Patients with severe renal impairment Post CABG patients Patients of acute coronary syndrome