FEASIBILITY AND ACCURACY OF DOPPLER-ECHOC ARDIOGRAPHIC MEASUREMENT OFPULMONARY BLOOD-FLOW IN 100 CONSECUTIVE CASES

One of the main advantages of Doppler echocardiography is the possibil ity of non-invasive measurement of blood flow at each valvular orifice . This method enables quantification of valvular regurgitation, the me asurement of Qp/Qs in cardiac disease with atrial or ventricular shunt s, and the interpretation of gradients and functional surface areas in valvular stenosis or prosthesis with respect to the underlying haemod ynamics. In each of these applications, the measurement of pulmonary b lood flow is valuable as the reference blood flow, and even indispensi ble in cases of shunts. The authors' objective was to study the feasab ility and accuracy of pulmonary flow measurement in 100 consecutive pa tients (40 women and 60 men, average age 56.7 +/- 17.5 years) with car diac disease (82 %) or healthy hearts (18 %). A grading from A to D wa s accorded depending on the technical difficulty of the examination, e ach grade having three degrees : 1) difficulty of recording and poor q uality Doppler spectrum, 2) difficulty of measuring orifice diameter b y 2D echocardiography, 3) necessity of analysis of color coded anterog rade flow to measure the pulmonary valvular orifice. Grade A was distr ibuted to easily recordable measurements with no difficulty ; grade B for measurements with one difficulty ; grade C for measurements with 2 difficulties and grade D for investigations judged to be impossible o r unreliable (3/3 criteria). The feasability of measurement of the car diac output at the pulmonary orifice was 88 % (A: 55 %, B: 25 %, C: 8 %). The correlation between the pulmonary flow and reference measureme nts at the aortic and/or mitral valve and/or mitral annulus was 0.96. The average difference between the pulmonary and reference flow was 51 +/- 273 cc/min. These values were not different in patients in whom t he measurement was judged to be difficult (grades B and C). In conclus ion, the excellent feasability and accuracy of pulmonary blood flow me asurement enables it to be used as a reference for quantification if i solated or associated mitral and aortic valve regurgitation.