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MRI-LGE Extent (% LV Mass Fibrosis): Comprehensive Explanation and Clinical Context This calculator estimates the proportion of myocardial fibrosis (late gadolinium enhancement, LGE) relative to total left ventricular (LV) mass using cardiac MRI data: %LGE = (LGE mass / LV mass) × 100. When input volumes are provided, they are converted to grams assuming a myocardial density of 1.05 g/mL. LGE reflects focal myocardia
Myocardial Flow Reserve (MFR): Explanation and Clinical Context Myocardial Flow Reserve (MFR) is a quantitative index derived from positron emission tomography (PET) myocardial perfusion imaging, calculated as the ratio of hyperemic (stress) myocardial blood flow (MBF) to resting MBF. An MFR value below 2.0 is considered abnormal and reflects impaired coronary vasodilator capacity, which may result from epicardial co
Calculate Global Longitudinal Strain (GLS), Global Circumferential Strain (GCS), and Global Radial Strain (GRS) Myocardial Strain (GLS, GCS, GRS): Comprehensive Explanation and Clinical Context Myocardial strain quantifies myocardial deformation as a percentage change from the end-diastolic state. Global Longitudinal Strain (GLS) reflects the shortening of subendocardial longitudinal fibers and is reported as a negat
Myocardial Work Efficiency Index (MWEI): Explanation and Clinical Context The Myocardial Work Efficiency Index (MWEI) is a novel, non-invasive echocardiographic parameter derived from left ventricular (LV) pressure–strain loops. It integrates LV deformation (strain) and afterload to evaluate the energy efficiency of myocardial contraction. The index is calculated as the ratio between Global Constructive Work (GCW)—th