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Left Atrial (LA) Volume Severity Index in Hypertrophic Cardiomyopathy (HCM): Explanation and Clinical Context The Left Atrial Volume Index (LAVI) is calculated as the left atrial volume (LAV) divided by the body surface area (BSA), providing a body size–adjusted measure of LA enlargement. LA enlargement in HCM reflects chronic diastolic dysfunction, elevated left ventricular filling pressures, and contributes to risk
LGE % Fibrosis Index (CMR): Explanation and Clinical Context The Late Gadolinium Enhancement (LGE) % Fibrosis Index is a quantitative measure of myocardial fibrosis obtained from cardiac magnetic resonance (CMR) imaging. It is calculated as the ratio of LGE mass to total left ventricular (LV) mass multiplied by 100, expressed as a percentage. Normal myocardium typically has minimal or no LGE; a value >5% suggests sig
LMNA Mutation Risk Score: Explanation and Clinical Context The LMNA mutation risk score is a clinical tool developed to predict the 5-year risk of life-threatening ventricular tachyarrhythmias (VTA) in patients with LMNA gene mutations. This score incorporates factors such as sex, presence of non-missense mutations, degree of atrioventricular block, occurrence of non-sustained ventricular tachycardia (NSVT), and left
LV Global Strain Abnormality Index (HCM/DCM): Explanation and Clinical Context The LV Global Strain Abnormality Index quantifies the extent of segmental myocardial dysfunction in patients with hypertrophic cardiomyopathy (HCM) or dilated cardiomyopathy (DCM). It combines global longitudinal strain (GLS) assessment and segmental strain abnormalities to provide a percentage score reflecting myocardial involvement. GLS
Left Ventricular (LV) Scar Burden: Explanation and Clinical Context LV Scar Burden (%) represents the proportion of left ventricular myocardial mass affected by fibrosis or infarction, typically quantified using Late Gadolinium Enhancement (LGE) on cardiac MRI. This parameter is clinically significant as higher LV scar burden is associated with an increased risk of ventricular arrhythmias, sudden cardiac death, and a
LV Wall Thickness Z-score: Explanation and Clinical Context The LV Wall Thickness Z-score is a standardized metric to assess left ventricular hypertrophy (LVH) relative to body size in children and adolescents. It compares the measured interventricular septal (IVS) and posterior wall thickness (LVPW) to age- and body size–specific normative data, providing a Z-score that indicates how many standard deviations the mea
LVOT Gradient Severity Index: Explanation and Clinical Context The LVOT Gradient Severity Index is a composite tool used to assess the severity of left ventricular outflow tract (LVOT) obstruction in patients, especially those with hypertrophic cardiomyopathy. It incorporates peak LVOT gradient, NYHA functional class, and presence of syncope to stratify patients into mild, moderate, or severe obstruction risk. This i