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PCAT Attenuation Index: Explanation and Clinical Context PCAT Attenuation Index measures the mean CT attenuation of pericoronary adipose tissue surrounding coronary arteries in Hounsfield Units (HU). It serves as a non-invasive biomarker of coronary inflammation, with higher (less negative) values reflecting greater inflammatory activity in the vessel wall. It is derived from coronary CT angiography by averaging the
Peguero–Lo Presti Index — explanation and clinical context The Peguero–Lo Presti index is an electrocardiographic voltage measurement calculated as the sum of the amplitude of the deepest S wave in any lead (Sdeepest) plus the amplitude of the S wave in lead V4 (SV4). The index is expressed in millivolts (mV). In the original derivation and subsequent validations, sex-specific cutoffs were recommended: a value > 2.3
Pulmonary Artery Systolic Pressure (PASP) Estimate: Explanation and Clinical Context The PASP estimate is derived from Doppler echocardiography using the peak tricuspid regurgitation (TR) velocity and an estimate of right atrial (RA) pressure. The formula 4 × (TR velocity)^2 + RA pressure provides an approximation of pulmonary artery systolic pressure in mmHg. Elevated PASP may indicate pulmonary hypertension, right
Pulmonary Vascular Resistance (PVR) Estimate Using TRV/VTIRVOT: Explanation and Clinical Context Pulmonary vascular resistance (PVR) is a critical parameter in assessing pulmonary hypertension. The TRV/VTIRVOT method provides a non-invasive echocardiographic estimate of PVR, based on the relationship between the peak tricuspid regurgitation velocity (TRV) and the right ventricular outflow tract time-velocity integral
Pulse Wave Velocity (PWV): Explanation and Clinical Context Pulse Wave Velocity is a non-invasive measure of arterial stiffness and a strong independent predictor of cardiovascular events and mortality. It reflects the speed at which the blood pressure pulse propagates through the arterial tree, with higher values indicating stiffer arteries. Clinical assessment of PWV provides early detection of vascular aging and h