Comparison of the current reasons for undergoing pharmacologic stress during echocardiographic and radionuclide stress testing.

BACKGROUND: Symptom-limited exercise is the preferred method of cardiac stress testing, but pharmacologic testing has been increasing over time. The exact reasons for pharmacologic stress testing have not been rigorously categorized. Thus, we systematically explored the reasons for pharmacologic stress testing in patients referred for cardiac stress imaging. METHODS: We studied consecutive patients referred for stress imaging [stress echocardiography or radionuclide myocardial perfusion imaging (MPI)] at Mount Sinai St Luke's hospital between August 2013 and April 2014. Baseline information was obtained using a standardized questionnaire and a trained physician triaged the patient for symptom-limited exercise stress testing or pharmacologic stress testing. RESULTS: In total, 551(48%) of our entire stress cohort underwent cardiac imaging following initial exercise testing and 589 (52%) underwent imaging with initial pharmacologic stress testing. Deconditioning and inability to walk (primarily due to musculoskeletal conditions) constituted the top two reasons for performing pharmacologic stress, followed by frailty, left bundle branch block (for MPI), resting wall motion abnormality (for echocardiography), and failed exercise attempts. The reasons for performing pharmacologic stress testing were similar in the MPI and echocardiography patients, despite a much higher level of disease acuity in the MPI group. CONCLUSIONS: We have applied a systematic approach for categorizing the reasons for pharmacologic stress. These reasons are heterogeneous, but similar across MPI and echo stress laboratories.

Prognostic Value of Stress Echocardiography in Patients Presenting with Syncope.

BACKGROUND: Evaluation for ischemia is appropriate in patients at risk for or with a history of coronary artery disease presenting with syncope. The aim of this study is to determine the prognostic value of stress echocardiography in patients presenting with syncope. METHODS: We examined our database of all patients undergoing stress echocardiography at our institution. Patients referred due to syncope were grouped as high risk based on any of the following: (1) known history of coronary artery disease, (2) left ventricular ejection fraction <50%, (3) moderate or severe mitral or aortic valve regurgitation, and (4) moderate mitral or aortic valve stenosis. The main outcomes were the presence of ischemia on stress imaging and all-cause mortality using the social security death index. RESULTS: A total of 225 patients were identified; mean age was 64.3 ± 14.5 years, the mean follow-up duration was 29.2 ± 13.8 months. There were 163 patients in the low-risk group and 62 patients in the high-risk group. On imaging, 7% of the overall cohort had ischemia. The low-risk group had 5 (3%) patients with ischemia and the high-risk group had 10 patients (16%) with ischemia (P < 0.01). The mortality rate was significantly higher in the high-risk group (3.99%/year vs. 1.02%/year; P = 0.02); this difference was not affected by the presence of ischemia. CONCLUSIONS: High-risk patients with syncope as defined by appropriateness criteria and existing evidence carry a higher risk of ischemia and all-cause mortality. The presence of ischemia may not be predictive of long-term outcome in this group.