Stress echocardiography: abnormal tissue Doppler imaging in the absence of cardiac allograft vasculopathy in heart transplant recipients.

BACKGROUND

The most significant predictor of long-term survival in heart transplant patients is the development of accelerated cardiac allograft vasculopathy (CAV). Several studies have demonstrated the usefulness of dobutamine stress echocardiography (DSE) for screening CAV, by detecting regional wall motion abnormalities. Tissue Doppler imaging (TDI)-derived indices during DSE allow for the early detection of ischemic heart disease (IHD), prior to a reduction in regional or global systolic function. These indices include a reduction in annular systolic velocity (S'), a decrease in early diastolic annular velocity (E'), and prolongation of time to E'. In cardiac transplant patients, the application of these TDI abnormalities during DSE remains unknown.

OBJECTIVE

The objective of this study was to evaluate the pattern of (TDI-derived indices of systolic and diastolic function during DSE in cardiac transplant patients without evidence of CAV.

METHODS

A retrospective evaluation of 30 patients (mean age 54 +/- 11 years) who had both DSE and coronary angiography was performed. The control group consisted of 15 patients referred to rule out coronary artery disease while the study group consisted of 15 cardiac transplant patients referred for routine annual follow-up. During each stage of DSE, tissue Doppler measurements of systolic (S'), early (E'), and late (A') diastolic velocities of the lateral annulus were taken.

RESULTS

All 30 patients had normal DSE based on systolic regional function and normal coronary angiograms with no stenosis >50%. There was no difference in hemodynamic parameters during the DSE at baseline and with stress. Despite normal coronaries, cardiac transplant patients demonstrated lower S', E', and A' velocities at peak stress compared to the control patients.

CONCLUSION

Dobutamine-induced augmentation of TDI velocities of the lateral annulus, normally observed in the absence of ischemia in nontransplanted adults, is reduced in cardiac transplant recipients.