1,329 calculators and references across 60 specialties, with formula confidence shown up front.
Z-Score Calculator for Aortic Root and Pulmonary Artery: Explanation and Clinical Context The Z-score represents how many standard deviations a measured aortic root or pulmonary artery diameter deviates from the mean expected diameter based on a patient's body surface area (BSA) and age. It is widely used in pediatric and adult cardiology to assess for aortic dilatation or pulmonary artery enlargement, which can indi
Z-score Coronary Origin (pediatric database): Explanation and Clinical Context This calculator normalizes measured coronary internal diameters to body size using a log-linear z-score model widely used in pediatric echocardiography. The typical modelling approach (used by Dallaire & Dahdah and others) fits a regression of the natural logarithm of coronary diameter (mm) against the natural logarithm of body surface are
Z-Score for Left Ventricular End-Diastolic Dimension (LVEDD): Explanation and Clinical Context Z-Score LVEDD provides a standardized method to assess left ventricular size relative to body size. It is calculated as the difference between the measured LVEDD and the predicted LVEDD (adjusted for body surface area), divided by the standard deviation from reference data. This score allows clinicians to identify abnormal
Z-score Pulmonary Artery (CHD Reference Model): Explanation and Clinical Context Z-score of the pulmonary artery is a dimensionless value that expresses how many standard deviations an individual’s pulmonary artery diameter deviates from the predicted mean for a given body size. In patients with congenital heart disease (CHD), accurate assessment of pulmonary artery size is crucial for surgical planning, prosthesis s
ZAHARA II Risk Model: Explanation and Clinical Context The ZAHARA II Risk Score is a validated tool to estimate maternal cardiac risk during pregnancy for women with known heart disease. It incorporates key clinical variables including maternal age, prior cardiac events, NYHA functional class, presence of left heart obstruction, left ventricular dysfunction, and mechanical heart valve. The score produces an individua
ZAHARA Risk Score: Explanation and Clinical Context The ZAHARA (Zwangerschap bij Aangeboren HARtAfwijking) risk score is a tool developed to assess the risk of adverse cardiac events during pregnancy in women with congenital heart disease. It incorporates eight clinical variables: history of arrhythmias, use of cardiac medications before pregnancy, New York Heart Association (NYHA) functional class greater than II, l
Zero-Fluoro Safety Index: Explanation and Clinical Context The Zero-Fluoro Safety Index is a predictive tool designed to estimate the safety and success probability of cardiac ablation procedures performed without fluoroscopy. Traditional fluoroscopy exposes both patients and staff to ionizing radiation, which may increase long-term health risks. This index incorporates key patient and procedural factors, including p
Zwolle Risk Score (Post-PCI): Comprehensive Explanation and Clinical Context The Zwolle Risk Score was developed to predict 30-day mortality and assess early discharge eligibility for STEMI patients after primary PCI. It incorporates six clinical and angiographic variables easily obtainable post-procedure: age, Killip class, TIMI flow, three-vessel disease, anterior infarction, and ischemic time. Clinical Significanc