Establishment of a canine model of acute pulmonary embolism with definite right ventricular dysfunction through introduced autologous blood clots

Abstract

PurposeTo establish a canine model of acute pulmonary embolism (PE) with right ventricular (RV) dysfunction using autologous blood clots and evaluate by echocardiography and contrast-enhanced Computed Tomography (CT). Materials and MethodsAutologous blood clots formed in vitro were introduced sequentially into the pulmonary arteries of eight healthy mixed-breed dogs while monitoring pulmonary and systemic hemodynamic function. Blood clots were injected until the mean pulmonary artery pressure (MPAP) reached two–three times the baseline pressure, which was maintained up to 1hour. The RV function was assessed by echocardiography and ECG-gated dual-source contrast CT. ResultsAll animals survived the imaging procedure. The post-injection pulmonary angiograms showed extensive PE, and MPAP increased from 16.50±2.45mmHg to 43.13±4.91mmHg (P<0.001). On echocardiography, the RV fractional area change decreased from 42.06±3.36 to 27.96±3.54 (P<0.001), and the RV myocardial performance increased from 0.20±0.05 to 0.63±0.16 (P<0.001). On CT, the RV end-systolic volume increased from 11.11±1.81ml to 24.71±4.60ml (P<0.001), RV end-diastolic volume from 20.73±2.83ml to 34.63±5.76ml (P<0.001), and the four-chamber RV/left ventricular diameter ratio from 0.38±0.07 to 0.81±0.14 (P<0.001). ConclusionAcute PE with RV dysfunction was established in a large animal model through controlled injection of autologous blood clots, which may be useful for developing and evaluating new therapeutic approaches for acute PE with RV dysfunction.