Three-Year Outcomes and Cost Analysis in Patients Receiving 64-Slice Computed Tomographic Coronary Angiography for Chest Pain

Sixty-four slice computed tomographic coronary angiography (CTCA) is being used more often in the evaluation of patients with chest pain. The strength of this test is its high specificity and negative predictive value in exclusion of coronary artery disease (CAD). Its use remains controversial because there are theoretical risks of radiation, additional costs of the test, and no long-term data to suggest that excluding CAD by use of this test results in positive patient outcomes. A total of 436 patients underwent 64-slice CTCA because of chest pain thought to be anginal. Cardiac computed tomography was ordered by the primary physician or cardiologist based on a low to intermediate pretest probability of flow-limiting CAD. A smaller subset of patients initially underwent stress testing but had equivocal findings or continued symptoms that warranted further evaluation. Of the total patient cohort, 376 had “no significant CAD” based on computed tomographic coronary angiographic results. Of the 60 patients who were believed on computed tomographic coronary angiogram to have “flow-limiting” CAD, 34 (57%) ended up having percutaneous coronary intervention or coronary artery bypass grafting. The remaining 26 patients (43%) did not have true flow-limiting disease on coronary catheterization and were treated medically. With follow-up of 36 months, 376 of those patients (100%) with minimal or no disease by CTCA were free of events or intervention. In conclusion, in a real-world, clinical setting, the negative predictive value of low-risk CTCA is very high and exceptionally helpful in predicting freedom from events for up to 3 years. By avoiding further invasive treatments, there is a significant potential cost savings in patients who are sent for noninvasive coronary angiography rather than invasive angiography.