Demographic, clinical, and echocardiographic factors associated with residual perfusion defects beyond six months after pulmonary embolism

BACKGROUND: Residual perfusion defects (RPD) after pulmonary embolism (PE) are common. PRIMARY AIM: This study aimed to determine the prevalence of RPD in a cohort diagnosed with PE 6-72 months earlier, and to determine demographic, clinical, and echocardiographic variables associated with RPD. METHODS: Patients aged 18-75 years with prior PE, confirmed by computed tomography pulmonary angiography 6-72 months earlier, were included. Participants (N = 286) completed a diagnostic work-up consisting of transthoracic echocardiography and ventilation/perfusion scintigraphy. Demographic, clinical, and echocardiographic characteristics between participants with RPD and those without RPD were explored in univariate analyses using t-test or Mann-Whitney U test. Multiple logistic regression analysis was used to assess the association between selected variables and RPD. RESULTS: RPD were detected in 72/286 patients (25.2 %, 95 % CI:20.5 %-30.5 %). Greater tricuspid annular plane systolic excursion (TAPSE) (adjusted odds ratio (aOR) 1.10, 95 % CI:1.00-1.21, p = 0.048) at echocardiographic follow-up, greater thrombotic burden at diagnosis, as assessed by mean bilateral proximal extension of the clot (MBPEC) score 3-4 (aOR 2.08, 95 % CI:1.06-4.06, p = 0.032), and unprovoked PE (aOR 2.25, 95 % CI:1.13-4.48, p = 0.021) were independently associated with increased risk of RPD, whereas increased pulmonary artery acceleration time was associated with a lower risk of RPD (aOR 0.72, 95 % CI:0.62-0.83, p < 0.001, per 10 ms). Dyspnoea was not associated with RPD. CONCLUSION: RPD were common after PE. Reduced pulmonary artery acceleration time and greater TAPSE on echocardiography at follow-up, greater thrombotic burden at diagnosis, and unprovoked PE were associated with RPD.