Tehran University of Medical Sciences The Research in Heart Yield and Translational Medicine (RHYTHM) 3115-7270 20 2 2025 09 27 97 104 Rojin Yaghubi Tabriz University of Medical Sciences Naser Khezerlou Cardiovascular Research Center, Tabriz University of Medical Sciences, Tabriz, Iran Soheil Nemati Cardiovascular Research Center, Tabriz University of Medical Sciences, Tabriz, Iran Hanieh Faraji Cardiovascular Research Center, Tabriz University of Medical Sciences, Tabriz, Iran Elnaz Javanshir Cardiovascular Research Center, Tabriz University of Medical Sciences, Tabriz, Iran Zahra Shamsian Cardiovascular Research Center, Tabriz University of Medical Sciences, Tabriz, Iran 2024 12 28 2025 06 23 Background: Mitral stenosis (MS) is typically assessed using both echocardiographic and invasive methods, which are critical for treatment planning. The present study analyzed the correlation between invasively measured left atrial pressure (LAP) and mitral valve area (MVA) assessed by three-dimensional transesophageal echocardiography (3D-TEE) in patients with rheumatic MS undergoing percutaneous transluminal mitral commissurotomy (PTMC). Methods: We conducted a cross-sectional study of 135 patients with severe rheumatic MS who were candidates for PTMC at Shahid Madani Heart Hospital, Tabriz, Iran, between April 2023 and April 2024. All patients underwent two-dimensional transthoracic echocardiography (2D-TTE) and 3D-TEE for MVA measurement. Invasive LAP and pulmonary pressures were recorded pre-procedure. Comparisons were made between patients with MVA<1 cm² and those with MVA≥1 cm². Results: The mean MVA measured by 3D-TEE was 1.03±0.07 cm². LAP was significantly higher in patients with MVA<1 cm² than in those with MVA≥1 cm² (P=0.040). Pulmonary artery pressures also differed significantly between the groups (P=0.016 and P=0.012). Among the 135 participants, 109 patients (63.3% with MVA<1 cm² and 93.6% with LAP>15 mm Hg) reported dyspnea, while 20 patients (65% with MVA<1 cm² and 100% with LAP>15 mm Hg) reported fatigue. Conclusions: In this study, we observed a significant correlation between invasive LAP and MVA measured by 3D-TEE. These findings suggest that invasive LAP measurement offers additional value in assessing the hemodynamic burden of severe MS. https://rhythm.tums.ac.ir/index.php/jthc/article/view/2214 https://rhythm.tums.ac.ir/index.php/jthc/article/download/2214/1202