Echocardiography in Patients with Pulmonary Embolism at Baseline and 1 Year Follow-up: Insights from the Evaluation of Long-term Outcomes after Pulmonary Emboli (ELOPE) Study

Avi Shimony ^1,2 Lawrence Rudski ² Andrew Hirsch ² Margaret Beddaoui ³ Arash Akaberi ³ David Anderson ⁴ Philip S Wells ⁵ Marc Rodger ⁶ Susan Solymoss ⁷ Michael Kovacs ⁸ Carole Dennie ⁹ Chris Rush ¹⁰ William H Geerts ¹¹ Paul Hernandez ⁴ Shawn Aaron ⁵ John T Granton ¹² Susan Kahn ¹³

¹Cardiology, Ben Gurion University, Soroka Medical Center
²Medicine, Jewish General Hospital, Montreal, QC
³Center for Clinical Epidemiology, Lady Davis Institute, Montreal, QC
⁴Medicine, Dalhousie University, Halifax, NS
⁵Medicine, The University of Ottawa, Ottawa, ON
⁶Hematology, The University of Ottawa, Ottawa, ON
⁷Medicine, McGill University, Montreal, QC
⁸Medicine, Hematology, University of Western Ontario, London, ON
⁹Diagnostic Imaging, The University of Ottawa, Ottawa, ON
¹⁰Nuclear Medicine, Jewish General Hospital, Montreal, QC
¹¹Medicine, Sunnybrook Health Sciences Centre, Toronto, ON
¹²Medicine, University of Toronto, Toronto, ON
¹³Center for Clinical Epidemiology, McGill University, Jewish General Hospital, Montreal, QC

Background: Most research relating to echocardiography in pulmonary embolism (PE) has focused on diagnosis and risk stratification for short-term outcomes. Few data examine the ability of echocardiography to predict long-term morbidity after PE.

Objectives: To describe echocardiographic parameters at baseline and 12-months in patients with acute PE and identify echocardiographic determinants of poor long-term outcomes.

Methods: Echocardiographic indices including strain from the ELOPE (Evaluation of Long-term Outcomes after PE) study, a prospective, multicenter cohort study of long-term outcomes after acute PE were analyzed. All Echocardiographic parameters were re-measured offline in a core lab in blinded manner.

Cardiopulmonary exercise testing (CPET) was performed at 1 and 12-months; the primary outcome of the study was maximal aerobic capacity defined by peak oxygen uptake (VO2) as a percent of predicted maximal VO2 (VO2max) CPET, with <80% predicted VO2max considered abnormal.

Results: 100 patients were enrolled in ELOPE study. Mean (SD) age was 50 (15) years, 57% male, 80% outpatients. The inter-rater agreements between Echocardiographers were very good.

At 1-year, 47% of patients had abnormal VO2max on CPET. These patients had lower right ventricular fractional area change (42±9 vs. 47±10 %; p=0.04), and were more likely to have abnormal (defined as ≥-20 %) RV 2D global strain (59% vs. 28%, p=0.044) at baseline, compared with patients who had normal VO2max at 12 months. Additionally, patients with abnormal VO2max at 1-month were more likely to have at baseline larger RVOT dimension (33±5 vs. 31±4 mm; p=0.02), and shorter pulmonary artery acceleration time (116±25 vs. 130±23 msec; p=0.01).

Conclusions: Echocardiography may serve as a useful tool for prediction of poor long term outcomes in patients with acute PE. Further analyses are in progress to assess the relationship between baseline to 1-year changes in echocardiographic indices and 1-year CPET results.