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Shunt Fraction Index (Qp:Qs Ratio): Explanation and Clinical Context The Qp:Qs ratio, also known as the Shunt Fraction Index, is used to quantify the magnitude of left-to-right cardiac shunts. It is defined as the ratio of pulmonary blood flow (Qp) to systemic blood flow (Qs). A Qp:Qs ratio of 1 indicates no shunt, while values above 1 indicate a left-to-right shunt, with higher values reflecting larger shunts. Clini
STAT Mortality Categories (STS–EACTS): Explanation and clinical context The STAT (Society of Thoracic Surgeons – European Association for Cardio-Thoracic Surgery) Mortality Scores and Categories are an empirically derived, procedure-based stratification system for congenital and pediatric cardiac surgery. Each index operation is assigned a numeric STAT score (range ~0.1–5.0) derived from large STS/EACTS registry data
— explanation and clinical context The STS Congenital Heart Surgery Database (CHSD) mortality risk approach stratifies operative risk primarily by procedure complexity (the STAT mortality category) and then adjusts for multiple patient-level factors (age group, weight/low birthweight, prior cardiothoracic operations, genetic/chromosomal abnormalities, non-cardiac congenital anomalies, multiple preoperative risk facto