• Echocardiography
• ischemia
• lung
• stress
• ultrasound

Background: In the field of lung ultrasound, B-lines are considered expression of extra-vascular lung water. The dynamic evaluation of B-lines during stress echo (SE), in addition to LV wall motion analysis, could help clinicians to identify functionally more severe forms of ischemia and make a more complete patients assessment.
Materials & methods: In our stress echo lab, we performed stress echocardiography (both exercise and pharmacological) and lung ultrasound for B-lines assessment in 273 patients referred for known/suspected CAD. Wall motion score index (WMSI) was calculated with a 17-segment model of LV at rest and peak stress. LUS assessment was performed with 4 site simplified scan, at rest and peak stress. A stress B-lines score > rest for ≥ 2 points was considered an abnormal (positive) response during stress.
Results: The feasibility of B-lines evaluation was 100%, with trivial additional scanning and analysis time. Stress B-lines positivity was detected in 67 patients (24%). At multivariate analysis, ischemia (OR =2,8; 95% CI 1,2-6,5 p<0.01), EF at stress (OR =0,9; 95% CI 0,92-0,99 p<0.01), history of diabetes were predictors of stress B-lines. Ischemia and a high peak WMSI were more frequent in patients with stress B-lines compared to those without B-lines (25 vs 10 %, p = 0,002).
Conclusion: Stress B-lines are positive in about 1 out of 4 patients, and more frequently in presence of ischemia, history of diabetes, high peak WMSI, lower EF. The dynamic integration of lung ultrasound and echocardiography can provide a more comprehensive functional characterization in patients with ischemic heart disease.