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Right Atrial (RA) Area Index: Explanation and Clinical Context The RA Area Index is calculated by dividing the right atrial area (measured by echocardiography) by the patient’s body surface area (BSA), providing a standardized measurement to assess right atrial enlargement. Normal RA area index is typically < 10.5 cm²/m². Values above this threshold indicate right atrial dilation, often associated with chronic pressu
Romhilt–Estes Point-Score System: Explanation and Clinical Context The Romhilt–Estes (R-E) point-score system is a composite electrocardiographic method developed to improve ECG detection of left ventricular hypertrophy by combining six ECG features (P-terminal force in V1, high QRS voltages, ST-T changes consistent with “strain”, left axis deviation, prolonged QRS duration, and delayed intrinsicoid deflection). Each
Right Ventricular Fractional Area Change (FAC): definition, clinical meaning and evidence-based context RV FAC quantifies global right ventricular systolic function from an RV-focused apical four-chamber view by tracing the RV endocardial border in end-diastole and end-systole and applying the equation: FAC (%) = 100 × (RV end-diastolic area − RV end-systolic area) / RV end-diastolic area. The American Society of Ech
Right Ventricle to Left Ventricle (RV/LV) Ratio on Echocardiography: Explanation and Clinical Context The RV/LV ratio is a measurement derived from echocardiography that compares the end-diastolic diameter of the right ventricle (RV) to the left ventricle (LV). It is widely used to assess right ventricular dilation, which can occur in conditions such as acute pulmonary embolism, pulmonary hypertension, right heart fa
RVOT VTI Cardiac Output Estimation in Pulmonary Hypertension: Explanation and Clinical Context RVOT VTI (Right Ventricular Outflow Tract Velocity Time Integral) is a Doppler echocardiography parameter used to estimate stroke volume and cardiac output, particularly in patients with pulmonary hypertension (PH). The stroke volume is calculated as the product of the RVOT cross-sectional area and the VTI, then multiplied