Background To investigate the value of colour Doppler echocardiography (CDE) in the closure of patent ductus arteriosus (PDA) in the elderly.
Methods Before the occlusion, screening the indicantions for twenty-five elderly patients with PDA by CDE. Using the shunt flow signal of colour Doppler flow imaging (CDFI) to estimate the pulmonary side diameter of PDA, compare with the angiocardiography and determine its accuracy through statistics. Using the continuous wave Doppler (CW) to measure peak velocity of tricuspid regurgitation and estimate cross-tricuspid pressure gradient according to the simplified Bernoulli equation ΔP = 4V2, together with the inherent right atrial pressure to estimate pulmonary artery pressure. Then compare cross-tricuspid pressure gradient and pulmonary artery pressure with cardiac catheterization. Determine its accuracy through statistics. All patients underwent interventional therapy and determine the efficacy of occlusion by CDE.
Results all the occlusion of the elderly patients with PDA was successful through the examination by CDE. The diameter of the PDA pulmonary side estimated by the shunt flow signal had a positive correlation with angiocardiography (r = 0.71, P < 0.001). Pulmonary artery pressure estimated by the CW had a positive correlation with cardiac catheterization contrast (r = 0.63, P < 0.001).
Conclusions CDE has an important value in the elderly during the procedure of patent ductus arteriosus occlusion. Using CDFI to estimate PDA pulmonary side diameter and CW to estimate pulmonary artery pressure before the occlusion is the key to screen the indication of occlusion. And it is also important for using CDFI to observe whether there was a residual PDA shunt after transcatheter closure.