P1403 Prognostic value of B-lines during stress lung ultrasound

Abstract OnBehalf Stress Echo 2020 study group of the Italian Society of Cardiovascular Imaging Background B-lines (also known as comets) by lung ultrasound (LUS) are a marker of pulmonary congestion and interstitial pulmonary edema during stress echocardiography (SE). Aim To assess the prognostic value of B-lines during SE. Methods We prospectively performed transthoracic echocardiography (TTE) and LUS (4-site simplified scan) evaluation at rest and peak stress in 1437 patients (age 63 ± 11 years; 874 males, 61%) referred for exercise (n = 581), vasodilator (n = 819: dipyridamole, n= 809 and adenosine, n= 10) or dobutamine (n = 37) SE for known or suspected coronary artery disease or heart failure. B-lines were assessed by LUS with a 4-site simplified scan (total score from 0-1, dry lung, to 40, alveolar pulmonary edema). Follow-up (median 16 months) was completed in all. Results B-lines were 1.14 [0-35] at rest and increased during stress (2.10 [0-40], p<.001). At individual patient analysis, B-lines appeared de novo/increased (≥2 points) during stress in 306 (21.3%), remained absent or fixed in 1097 (76.3%) and decreased/disappeared in 34 (2.4%). At follow-up, there were 174 events: 17 deaths, 14 non-fatal myocardial infarctions, 51 hospital admissions for acute heart failures, and 92 late (> 3 months from SE) myocardial revascularizations. At multivariable analysis, stress-induced regional wall motion abnormalities (Hazard Ratio, HR, 2.842, 95% Confidence Intervals, CI: 2.016-4.005, p<.0.001) and B-lines change during stress (HR 1.471, 95% CI: 1.054-2.052, p=.022) were independent predictors. Kaplan-Meier curves showed progressively worsening event-free survival for 943 pts with absent (score 0-1), 333 with mild (2-5), 90 with moderate (6-10) and 71 with severe (>10) B-lines at peak stress: see figure. Conclusion B-lines by LUS are a useful adjunct to regional wall motion abnormalities for risk stratification during SE. The presence and number of B-lines during stress allow a titration of risk. The outcome is darker with more comets in the SE sky. Abstract P1403 Figure. Survival curves and peak stress B-lines