Background: Right ventricular dysfunction has been observed in uremic patients receiving percutaneous transluminal angioplasty (PTA). This prospective study focuses on the impact of tissue Doppler imaging echocardiographic parameters on assessing right ventricle function in uremic patients post PTA of dysfunctional hemodialysis access.
Methods: Sixty uremic patients were divided into two groups by angiographic findings: an occlusive group (26 patients) and a stenotic group (34 patients). All uremic patients underwent routine echocardiography with tissue Doppler imaging both before and immediately following PTA to assess the right ventricular (RV) function and pulmonary artery systolic pressure (PASP). The right ventricular (RV) myocardial performance index (MPI) was obtained during tissue Doppler imaging over the lateral tricuspid annulus. The M index was measured and defined as the peak early diastolic mitral inflow velocity divided by the RV MPI. The RV MPI, RV isovolumic relaxation time (IVRT) and M-index were used to evaluate RV function post-PTA.
Results: Immediately following PTA, PASP (31.6 ± 11.3 mmHg versus 42.6 ± 12.0 mmHg, p = 0.001), RV MPI (0.46 ± 0.08 versus 0.62 ± 0.13, p < 0.001) and IVRT (75.1 ± 12.9 versus 98.4 ± 27.7 ms, p < 0.001) increased significantly in the occlusive group. However, PASP and RV function did not change significantly in the stenotic group. In 42.3% patients from the occlusive group, the M-index fell below 112 and RV MPI rose above 0.55 post-PTA; this occurred in only 8.8% of the stenotic group.
Conclusions: This prospective study demonstrated that there was a higher incidence of RV dysfunction in uremic patients with elevated PASP with totally occluded hemodialysis access than those with stenotic access post-PTA.
Key words: Myocardial performance index; Percutaneous transluminal angioplasty; Pulmonary hypertension; Tissue Doppler image; Uremic.