Stress echocardiography: abnormal response of tissue Doppler-derived indices to dobutamine in the absence of obstructive coronary artery disease in patients with chronic renal failure.

BACKGROUND: Abnormal tissue Doppler (TD)-derived indices during dobutamine stress echocardiography (DSE) can predict the presence of coronary artery disease (CAD) in patients with normal renal function. These indices include a reduction in annular systolic velocity (S'), a decrease in early diastolic annular velocity (E'), and prolongation of the time to E'. However, the ability of these indices to detect or exclude CAD in patients with chronic renal failure (CRF) is unclear.

OBJECTIVE: To examine the ability of TD-derived indices to detect or exclude the presence of CAD in patients with CRF.

METHODS: We evaluated a total of 30 patients (13 males, mean age 57 +/- 15 years) using both DSE and coronary angiography. This cohort consisted of 12 control patients with normal renal function (mean creatinine 0.5 mg/dL) and 18 patient with CRF (mean creatinine 2.5 mg/dL). At each stage of the DSE, left ventricular (LV) diastolic function was assessed using conventional (peak early (E) and late (A) transmitral, E/A ratio, E-wave deceleration time (DT), and isovolumic relaxation time (IVRT)) and TD-derived indices (lateral annular systolic (S'), early diastolic (E'), and late atrial velocities (A'), time to E' and E/E').

RESULTS: All 30 patients had a normal DSE based on systolic regional function and a normal coronary angiogram. There was no difference in E, A, E/A, DT or IVRT between the two groups at each stage. Despite normal coronaries, patients with CRF demonstrated lower S' and E' velocities at peak stress compared to the control patients (8.0 +/- 2.2 cm/sec vs 15.1 +/- 2.6, P < 0.05 and 6.7 +/- 1.6 cm/sec vs 13.3 +/- 3.1, P < 0.05, respectively). During DSE, the time to E' at peak stress in CRF patients was also prolonged compared to control (400 +/- 44 ms vs 329 +/- 51, P < 0.05). Patients with CRF also had increased filling pressures (as estimated by E/E') as compared to controls at peak stress (14.7 +/- 5.2 vs 7.4 +/- 1.5, P < 0.05, respectively).

CONCLUSION: In patients with CRF, a reduction in TD derived indices does not predict the presence of obstructive CAD.