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Left Atrial Volume Index (LAVI): Explanation and Clinical Context LAVI represents the left atrial volume indexed to body surface area and serves as a reliable marker of chronic diastolic burden. Enlargement of the left atrium occurs gradually as a consequence of prolonged elevation of left ventricular filling pressure. Because of this, LAVI is considered a structural biomarker that reflects chronic diastolic dysfunct
LGE Extent (% Myocardium Scarred): Explanation and Clinical Context LGE (Late Gadolinium Enhancement) imaging by cardiac MRI allows quantification of myocardial scar tissue, expressed as a percentage of total left ventricular (LV) myocardial mass. The LGE extent is calculated as (Scar Mass / Total LV Myocardial Mass) × 100. Low values (0–5%) represent minimal or no fibrosis, while higher percentages indicate signific
Left Ventricular Diastolic Dysfunction Grade (ASE 2016): Explanation and Clinical Context LV diastolic dysfunction refers to abnormal filling and relaxation of the left ventricle. ASE 2016 recommends an integrative approach using four parameters: E/e' ratio, septal e', TR velocity, and left atrial volume index (LAVI). Grade I represents impaired relaxation with normal filling pressures, Grade II represents pseudonorm
LV End-Diastolic Volume Index (LVEDVI): Explanation and Clinical Context LV End-Diastolic Volume Index (LVEDVI) represents the volume of blood in the left ventricle at the end of diastole, normalized to body surface area (BSA). It is a fundamental echocardiographic parameter to assess left ventricular size and remodeling. In clinical practice, LVEDVI helps detect dilated cardiomyopathy, monitor heart failure progress
Left Ventricular Mass (LVM) by MRI: Explanation and Clinical Context Left ventricular mass (LVM) is a crucial parameter reflecting the myocardial muscle mass of the left ventricle. Accurate assessment using cardiac MRI provides precise volumetric measurements and is considered the gold standard compared to echocardiography. The Devereux formula adapted for MRI calculates LVM using the cube method based on left ventri
Left Ventricular Mass Index (LVMI): Explanation and Clinical Context Left ventricular mass index is a key echocardiographic parameter used to quantify the extent of cardiac structural remodeling associated with pressure or volume overload. The Devereux formula is the most validated method for estimating left ventricular mass using linear measurements obtained from parasternal long axis imaging. The resulting left ven
Left Ventricular Sphericity Index (LVSI): Explanation and Clinical Context The Left Ventricular Sphericity Index (LVSI) is a ratio of the left ventricular short-axis diameter to the long-axis length measured at end-diastole. It quantifies the geometric remodeling of the left ventricle from a normal ellipsoid shape toward a more spherical form. A higher LVSI indicates a more spherical ventricle, which is often associa
Sokolow–Lyon Index (SV1 + tallest R in V5 or V6): Explanation and Clinical Context The Sokolow–Lyon Index is a classic electrocardiographic voltage criterion for detecting left ventricular hypertrophy (LVH). It is calculated as the depth of the S wave in lead V1 plus the amplitude of the tallest R wave in lead V5 or V6 (measured in millimetres). A summed value > 35 mm (3.5 mV) is the conventional cut-off suggesting L
LVOT VTI (Stroke Volume) Estimation: Explanation and Clinical Context The LVOT VTI (Left Ventricular Outflow Tract Velocity Time Integral) combined with the LVOT diameter allows estimation of stroke volume (SV) by calculating the LVOT cross-sectional area and multiplying it by the VTI. Stroke volume represents the volume of blood ejected from the left ventricle during a single cardiac cycle. Accurate estimation is im