Comparative feasibility of dobutamine stress echocardiography performed with and without intravenous contrast in patients with class III obesity.

BACKGROUND: Concern exists regarding adequacy of visualization of stress echocardiograms performed without intravenous contrast in persons with Class III obesity (body mass index ≥ 40 kg/m2 ). METHODS: Dobutamine stress echocardiography (DSE) was performed on 128 candidates for bariatric surgery with class III obesity without chest pain or pre-existent coronary artery disease (CAD). DSE without intravenous contrast was initially performed on 62 patients with class III obesity, then was subsequently was performed with intravenous contrast on 66 patients with class III obesity. Left ventricular (LV) regional wall motion was assessed at baseline and peak stress using the 16-segment model. RESULTS: In the intravenous contrast group, 1046 of 1056 LV segments studied (99.1%) were well-visualized and interpretable at baseline and 1044 of 1056 LV segments studied (98.9%) were well-visualized and interpretable at peak stress. In the non-contrast group, 905 of 992 segments studied (91.2%) were well-visualized and interpretable at baseline and 886 of 992 segments studied (89.3%) were well-visualized and interpretable at peak stress. A significantly greater number of LV segments were well-visualized and interpretable in the intravenous contrast group than in the group compared to the non-contrast group, at baseline and at peak stress (p < 0.00001 for both). DSE was positive for ischemia in one patient. All patients underwent bariatric surgery without cardiovascular complications. Six months after surgery, all patients were alive; none developed cardiovascular events. CONCLUSION: The use of intravenous contrast during DSE significantly improves visualization and interpretability of LV segments in patients with class III obesity.

Novel Assessment of Ischemia in Patients With Anomalous Right Coronary Artery.

Anomalous right coronary arteries are usually benign; however, sudden death owing to myocardial ischemia, especially during exertion, have been reported in patients with intramural or interarterial course, which is likely due to dynamic obstruction. We propose a novel method of physiological evaluation with instantaneous wave-free ratio with dobutamine infusion to simulate controlled dynamic obstruction in anomalous right coronary arteries. (Level of Difficulty: Intermediate.).