Nuclear Stress Testing Referrals: Time for a Novel Radiation Sparing Approach?

Abstract

Background: A Science Advisory from the American Heart Association implores clinicians to always consider equivalent tests which do not use ionizing radiation. Intersocietal guidelines describe only two scenarios where a nuclear stress test is the only option for non-invasive evaluation: left bundle branch block (LBBB) and ventricular-paced rhythm; otherwise, treadmill EKG and stress echocardiography are feasible. This study sought to measure our compliance with appropriate use criteria,6 and then to apply our own Novel Radiation Sparing Approach (NRSA) to measure what percentage could have been evaluated without radiation. Methods: The appropriateness of each referral for nuclear stress testing was evaluated using the AUC. Our NRSA was then applied, reserving a grade of 'appropriate' for patients with LBBB, pacemaker, or known resting wall motion abnormalities. The rate of appropriate referrals was then compared using McNemar's test. Results: We analyzed 423 consecutive referrals between Aug 2010 and Feb 2012. Median age was 64 yr; males comprised 57.2% of all patients; and 64.8% were outpatient. Chest pain and dyspnea were the most common reasons for referral. The rate of appropriate referrals at our facility using the AUC was 93.6%. When applying our NRSA, nuclear stress testing was the required or 'appropriate' test in only 17.7% of our patients (p < 0.001, McNemar's test). Conclusions: According to the current AUC, our facility is referring patients appropriately for nuclear stress testing. However, by reserving nuclear stress testing primarily for patients with LBBB, pacemaker, and baseline wall motion abnormalities, we can reduce radiation exposure to our patients while still providing appropriate evaluation.