Abstract 17415: Dobutamine Stress Echocardiography Does Not Predict Outcomes in Patients with Low Transvalvular Gradient Undergoing Transcatheter Aortic Valve Replacement
Introduction: Patients with severe aortic stenosis and low mean transvalvular gradient have poor outcomes with an estimated 30 day post-surgical Aortic Valve Replacement (AVR) mortality of 21%. Low Dose Dobutamine Stress Echocardiography (LD-DSE) is performed in these patients for further risk stratification by determining the presence of myocardial reserve - defined as an at least 20% increase in stroke volume with Dobutamine infusion. These patients have lower perioperative mortality. However, it is unclear if LD-DSE can predict outcomes in high surgical risk patients undergoing Transcatheter Aortic Valve Implantation (TAVI).
Methods: We retrospectively identified patients from the PARTNER trial who underwent TAVI and had a LD-DSE as part of the inclusion criteria when the resting mean aortic gradient is <40 mmHg. Outcomes identified in these patients after TAVI include re-hospitalizations for cardiac causes and mortality at 30 days and at one year.
Results: Twenty-four patients who underwent TAVI were identified; 63% were male, and the average age was 82±8. Six patients (31%) had myocardial reserve. By 30 days post-TAVI, 4 patients (16.7%) were hospitalized for cardiac causes, and 2 patients (8.8%) died. At one year there were no other events. There was no significant difference in mortality or re-hospitalization rates at 30 days and at one year between patients with and without myocardial reserve based on LD-DSE.
Conclusion: In this small retrospective study of high risk patients undergoing TAVI, LD-DSE was not able to provide further risk stratification for short and intermediate term outcomes. Myocardial reserve may not be as important for TAVI as is for surgical AVR. Further larger studies will need to be performed to verify these findings
- © 2012 by American Heart Association, Inc.