Coronary angiography, lesion classification and severity assessment.

A joint task force of the American College of Cardiology and the American Heart Association established criteria in 1988 to estimate procedural success and complication rates after balloon angioplasty, based on the presence or absence of specific lesion characteristics. Advances in the technique of coronary intervention over the years have changed the management of patients who have coronary artery disease, resulting in safer and more effective percutaneous revascularization in patients previously deemed at high risk for nonsurgical approaches. Coronary angiography (visual or quantitative) is a simple,easy, and mostly reliable tool in the assessment of lesion severity, but it may be inconclusive in the borderline lesions (40% to 60% diameter obstruction). Anatomical (using intravascular ultrasound) and physiological (using coronary flow reserve or fractional flow reserve) lesion assessment may be required for adequate lesion evaluation, before and after percutaneous coronary intervention.