A Guide to Interpreting Preoperative Cardiac Studies

Abstract

Patients referred for cardiac surgery undergo extensive preoperative cardiac as well as noncardiac evaluation. Basic cardiac tests include a baseline electrocardiogram (ECG), a transthoracic echocardiogram (TTE), and a cardiac catheterization. Additional tests such as a transesophageal echocardiogram (TEE), a computed tomography (CT) scan, or a cardiac magnetic resonance imaging (CMR) are done in specific circumstances. The baseline ECG is valuable for comparison with later ECGs if new changes should occur, and it can reveal evidence of myocardial ischemia and detects cardiac arrhythmia. The echocardiogram fully assesses the left and right ventricular function as well as the valvular function. Cardiac catheterization provides invasive hemodynamic assessment, but most importantly it defines the coronary anatomy and the presence and severity of coronary artery disease (CAD). Measurement of fractional flow reserve (FFR) and conducting intravascular ultrasound (IVUS) are additional tools available through cardiac catheterization that can assess coronary flow and the vessel morphology, respectively.