A retrospective analysis of 717 patients with calcific mitral stenosis (CMS) found a 46% mortality rate over three years of follow-up, with severe cases defined as mitral valve area ≤1.5 cm². The condition predominantly affects older women (mean age 74 years) and represents an increasingly common form of heart valve disease as populations age. Mean transmitral gradient emerged as the strongest predictor of poor outcomes, while traditional echocardiographic measures proved unreliable for severity assessment. This research addresses a critical knowledge gap in cardiovascular medicine. As life expectancy increases, calcific heart valve diseases are becoming more prevalent, yet standardized assessment methods remain underdeveloped compared to rheumatic valve disease. The finding that nearly half of CMS patients died within three years underscores the serious nature of this condition, challenging assumptions that age-related valve calcification is benign. The identification of mean gradient as a key prognostic marker could improve risk stratification in clinical practice. However, this preprint awaits peer review, and the retrospective design limits causal inferences. The results suggest CMS warrants more aggressive monitoring and potentially earlier intervention than currently practiced.