CT Pericardial Thickness Index (PTI) Calculator

CT Pericardial Thickness Index (PTI): Explanation and Clinical Context The CT Pericardial Thickness Index (PTI) is a standardized measure of pericardial thickness adjusted for body surface area (BSA), providing a more individualized assessment of pericardial remodeling or constriction. Pericardial thickening >4 mm/m² is considered abnormal and may indicate constrictive pericarditis or risk for hemodynamic compromise. This index allows clinicians to normalize CT measurements across patients of different body sizes.

PTI is particularly useful in differentiating constrictive pericarditis from restrictive cardiomyopathy in patients with heart failure symptoms. Accurate measurement of pericardial thickness is obtained using high-resolution CT, and BSA is calculated using standard formulas such as Mosteller or Du Bois. PTI enhances risk stratification by identifying patients at higher risk of pericardial constriction who may benefit from further evaluation or pericardiectomy.