Reasons for Disagreement Between Screening and Standard Echocardiography in Primary Care: Data from the PROVAR+ Study

Purpose: To evaluate the reasons for disagreement between screening echocardiography (echo), acquired by non-experts, and standard echo in the Brazilian primary care (PC). Methods: : Over 20 months, 22 PC workers were trained on simplified handheld (GE VSCAN) echo protocols. Screening groups, consisting of patients aged 17-20, 35-40 and 60-65 years, and patients referred for clinical indications underwent focused echo. Studies were remotely interpreted in US and Brazil, and those diagnosed with major or severe HD were referred for standard echo performed by an expert. Major HD was defined as moderate to severe valve disease, ventricular dysfunction/hypertrophy, pericardial effusion or wall-motion abnormalities. A random sample of exams was selected for evaluation of variables accounting for disagreement. Results: : A sample of 768 patients was analyzed, 651 (85%) in the referred group. Quality issues were reported in 5.8%, and the random Kappa for major HD between screening and standard echo was 0.51. The most frequent reasons for disagreement were: overestimation of mitral regurgitation (MR) (17.9%, N=138), left ventricular (LV) dysfunction (15.7%, N=121), aortic regurgitation (AR) (15.2%, N=117), LV hypertrophy (13.5%, N=104) and tricuspid regurgitation (12.7%, N=98). Misdiagnosis of mitral and aortic morphological abnormalities was observed in 12.4% and 3.0%, and underestimation of AR and MR occurred in 4.6% and 11.1%. Among 257 patients with suspected mild/moderate MR, 129 were reclassified to normal. Conclusion: Although screening echo with task-shifting in PC is a promising tool in low-income areas, estimation of valve regurgitation and LV function and size account for considerable disagreement with standard exams.