Clinical practices in imaging rheumatic mitral stenosis: a multinational survey in Brazil and Portuguese-speaking countries

Abstract

Abstract Background Rheumatic heart disease (RHD) remains a major cause of valvular disease in low- and middle-income countries, with substantial public health and economic impact. Cardiac imaging, particularly echocardiography (echo), plays a pivotal role in diagnosing and managing RHD, particularly mitral stenosis (MS), yet practices vary across affected regions. Purpose To evaluate current use of cardiac imaging in the assessment and management of RHD – focusing on MS- in Brazil and Portuguese-speaking countries, through a collaborative survey coordinated by the Cardiovascular Imaging Department of the Brazilian Society of Cardiology. Methods An anonymous questionnaire was distributed via messaging platforms to cardiologists and cardiovascular imaging specialists. Data on clinical experience, imaging modalities, and decision-making strategies related to MS were collected and analyzed. Results A total of 439 participants completed the survey, predominantly from Brazil (89.7%) and Angola (67.4% of the remaining 10.3%). Most reported over 10 years of clinical experience (67.4%), worked in public hospitals (58.5%), and were based in tertiary centers (61.9%). Conventional parameters (2D planimetry, PHT, and transvalvular gradients) were the most frequently used methods to assess MS. In addition to conventional two-dimensional (2D) measurements, strain imaging is used in clinical routine by 77.7%, three-dimensional (3D) echo in 51.5% and exercise echo in 35.3%. Regarding the classification, 50.1% considered mitral valve area (MVA) between 2.0–2.5 cm² as mild. In cases of discordant clinical-echo scenarios, 3D planimetry and exercise echo were used by 35.5% and 36%, respectively. Left ventricular (LV) systolic function was primarily evaluated using biplanar ejection fraction (EF) by Simpson’s method (86.6%), followed by 2D longitudinal strain in selected cases (42.8%), LVEF by 3D echo (26%), and cardiac magnetic resonance (20%). Assessment of right ventricular function was most commonly performed using TAPSE and RV tissue Doppler (90.9%), followed by fractional area change (FAC) (62.2%), 2D RV strain (31.9%), RVEF by 3D echo (20.5%), and CMR (18.9%). Percutaneous balloon mitral valvuloplasty (PBMV) was primarily guided by the Block-Wilkins score (78.1%), with special consideration to subvalvular involvement (77.2%) and valve calcification (68.3%). Intraprocedural echo guidance was reported in 87.1% of centers performing PBMV with the use of 2D transesophageal echo (TOE) in 39.2%, 3D TOE in 45.6%, and 2D transthoracic echo in 15.2%. Conclusion 2D transthoracic echo remains the cornerstone for RHD assessment. Although access to advanced imaging techniques, such as strain and 3D echo is increasing, their integration into routine clinical-decision making is still limited. Furthermore, the variability in defining mild MS reveals a knowledge gap and reinforces the need for broader training and guideline standardization across Portuguese-speaking countries.