11. Cardiac Catheterization

Diagnostic cardiac catheterization is recommended whenever it is clinically important to define the presence or severity of a suspected cardiac lesion that cannot be evaluated adequately by noninvasive techniques. Because the risk of a major complication from cardiac catheterization is less than 1 % with mortality of less than 0.08 %, there are few patients who cannot be studied safely in an active laboratory. Intracardiac pressure measurements and coronary arteriography are procedures that can be performed with reproducible accuracy best by invasive catheterization. Identification of coronary artery disease and assessment of its extent and severity are the most common indications for cardiac catheterization in adults. The information obtained is crucial to optimize the selection of mechanical or medical therapy. In addition, dynamic coronary vascular lesions, such as spasm, myocardial bridging, and plaque rupture with thrombosis, can be identified. The consequences of coronary heart disease, such as ischemic mitral regurgitation and left ventricular (LV) dysfunction, can be defined. Cardiac catheterization should be considered a diagnostic test used in combination with complementary noninvasive tests. This allows catheterization to be directed and simplified without obtaining redundant anatomic information that is reliably available through echocardiography and cardiac magnetic resonance. There is no true absolute contraindication to cardiac catheterization other than refusal of the competent patient. The procedure can be successfully performed even in the most critically ill patient with a relatively low risk.