P4986Quadruple imaging exercise stress echocardiography in unexplained dyspnoea

Abstract

Abstract Background Current guidelines recommend the use of exercise stress echocardiography (ESE) in patients with unexplained dyspnoea. The methodological standard of ESE was recently reshaped with the quadruple imaging protocol, mainly tested in patients with chest pain. Aim of this study was to define the ESE pattern of response in patients with dyspnoea as the main symptom Methods From the initial population on a 1-year cohort of 604 patients referred in a single center for clinically-driven semi-supine ESE, we selected a subset of 93 consecutive patients (age 63±9 years, 52 females, resting Ejection fraction = 64±7%) with exertional dyspnea (shortness of breath, exertional fatigue or poor exercise capacity). All underwent quadruple imaging ESE: 1- Regional wall motion abnormalities (RWMA, step A) assessment (with wall motion score index, WMSI); 2- B-lines (step B) with simplified 4-site scan, each space scored from 0 = black, to 10= white (positivity criterion: stress score > rest for at least 2 points); 3- Left ventricle contractile reserve (LVCR, step C) assessment with stress/rest ratio of LV force measured as systolic blood pressure/end-systolic volume (positivity criterion:<2.0); 4- Pulsed-wave Doppler coronary flow velocity reserve (CFVR, step D) assessment in mid-distal LAD (positivity criterion: stress/rest diastolic peak flow velocity <2.0). Readers were accredited for each parameter upstream to recruitment via a web-based system. Results Feasibility was 100% for steps A, B and C, and 82% for step D. RWMA were present in 56 patients (60%). Of them, 27 underwent coronary angiography verification, showing significant coronary artery disease in 81%. B-lines positivity occurred in 35 patients (38%), an abnormal LVCR in 63 patients (68%), and a reduced CFVR in 44 pts (55%). At least one positivity criterion was observed in 80 patients (86%). Conclusions Patients with unexplained dyspnea are a reason of referral to ESE, accounting for 15% of contemporary testing. Quadruple imaging is useful to document the origin of dyspnoea as an ischemic equivalent (A positivity) and/or its cardiogenic origin for acute backward failure with pulmonary congestion (B positivity), myocardial function abnormalities (C positivity), and reduction of CFVR of microvascular-epicardial-myocardial origin (D positivity). Dyspnoea of unexplained origin is a multifactorial problem, and a more comprehensive assessment of these patients during ESE expands the clinical potential of the method.