CONTRAST ECHOCARDIOGRAPHY IN CORONARY-ARTERY DISEASED PATIENTS - EFFECT OF SYSTEMIC AND PULMONARY-ARTERY PRESSURES ON LEFT-HEART OPACIFICATION AFTER INTRAVENOUS-INJECTION OF ALBUNEX

Background Contrast echocardiography is a useful tool for assessing re peatedly patients with coronary artery disease, Nevertheless, elevated pulmonary artery and systemic blood pressures likely to be associated with cardiac ischemia may limit the left Ventricular opacification (L VO) because of the microspheres' sensitivity to pressure. Objective To determine the effects of systemic and pulmonary artery blood pressure s on LVO. Methods We performed 55 intravenous injections (0.08 and 0.2 2 ml/kg) of a new transpulmonary contrast agent (Albunex), during two separated exposures, into 20 cardiac ischemic patients while monitorin g invasively their cardiac indexes, and intracardiac, systemic, and pu lmonary artery blood pressures. LVO was graded qualitatively from fain t to full. Results A logistic model with the grade of LVO as the depen dent variable and a selection from among the dose, exposure, right and left atrial blood pressures, systolic systemic and pulmonary artery b lood pressures (ranges 94-208 and 14-45 mmHg, respectively), cardiac i ndex, stroke index, and pulmonary and systemic vascular resistances as the explanatory variables demonstrated that increasing the dose gives an increasing probability of LVO (P = 0.02) and that increasing the p ulmonary artery pressure reduces that probability (P = 0.006), A decre ased cardiac index tended also to be associated with decreased LVO, Th e systemic blood pressure and the pulmonary and systemic vascular resi stances had no statistically significant effect on the grade of LVO. C onclusions LVO after intravenous administration of Albunex is dose-dep endent and limited by an elevated pulmonary artery pressure, These dat a suggest that one should use higher doses for cardiac ischemic patien ts with elevated pulmonary artery pressures and that use of Albunex ha s the potential to detect pulmonary hypertension in patients.