Comparative prognostic significance of transesophageal versus transthoracic stress echocardiography

Patients with a negative transthoracic stress echocardiographic study (TTE-SE) are at low risk for adverse cardiac events. Because of a higher sensitivity for detection of coronary artery disease, transesophageal dobutamine stress echocardiography (TEE-DSE) might permit identification of an even lower risk population. We compared the relative prognostic values of TTE-SE and TEE-DSE in 236 patients with negative stress echocardiograms. Baseline and follow-up information on 236 consecutive subjects who had a negative stress echocardiographic study during the period of October 1996 to December 1997 was obtained. Baseline cardiac risk factors and major cardiac events (nonfatal myocardial infarct or cardiac death) were identified. Follow-up was obtained in 233 subjects for a mean duration of 25 months. At baseline, the TEE-DSE group had more hypertensives (85% vs 67%, P = 0.02) and more baseline wall-motion abnormalities (41% vs 26%, P = 0.03). At 34 months of follow-up, there was no significant difference in the occurrence of major cardiac events between the two groups (8% vs 8.6%, P = NS). In the TEE-DSE group, there were more than twice as many events in the second year of follow-up as compared with the first year, indicating that a negative TEE-DSE has lessened prognostic value 1 year after the test. Standard TTE-SE provides prognostic data in patients at high risk for major cardiac ischemic events that is equivalent to that obtained by TEE-DSE. While advances in ultrasound techniques may improve our ability to detect coronary artery disease, it remains to be seen whether this will have an impact on prognostication.