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The 4PEPS Pulmonary Embolism Clinical Probability Score is a validated clinical tool designed to estimate the pretest probability of acute pulmonary embolism using readily available clinical variables. 4PEPS Pulmonary Embolism Clinical Probability Score Explanation and Clinical Context The 4PEPS score is a simplified clinical prediction rule developed to estimate the pretest probability of acute pulmonary embolism us
6-Minute Walk Distance (6MWD) Adjustment for Age/Sex in Pulmonary Hypertension Risk: Explanation and Clinical Context The six-minute walk test (6MWT) measures the distance a patient can walk on a flat surface in six minutes (6MWD). In patients with pulmonary hypertension (PH) the 6MWD is a strong prognostic marker: shorter distances are associated with worse outcomes and higher mortality. However, because 6MWD is inf
Balloon Pulmonary Angioplasty (BPA) Success Score: Explanation and Clinical Context Balloon Pulmonary Angioplasty (BPA) is an interventional therapy for patients with inoperable or residual chronic thromboembolic pulmonary hypertension (CTEPH). The BPA Success Score estimates the likelihood of achieving hemodynamic normalization (mean pulmonary artery pressure < 25 mmHg) following a series of BPA sessions. The score
Value Enter numeric value in ng/L (e.g., 275 or 275.5). Risk Model -- choose -- ESC/ERS 3-Strata (Low / Intermediate / High) COMPERA 2.0 Four-Strata (Low / Intermediate-Low / Intermediate-High / High) BNP/NT-proBNP Cutoffs in Pulmonary Hypertension: Explanation and Clinical Context Brain natriuretic peptide (BNP) and N-terminal pro-BNP (NT-proBNP) are key biomarkers of right ventricular strain and adverse prognosis i
Known hypothyroidism -- select -- Yes No Symptom onset > 2 weeks before index PE diagnosis -- select -- Yes No Right ventricular dysfunction on CT or echocardiography (at index PE) -- select -- Yes No Known diabetes mellitus -- select -- Yes No Thrombolytic therapy or embolectomy for the acute PE event -- select -- Yes No CTEPH Prediction Score: Explanation and Clinical Context Chronic thromboembolic pulmonary hypert
Calculator mode This tool supports two peer-reviewed approaches: 1) CTEPH segmental scoring (Abozeed et al., 2022): Perfusion Defect (PD) Score = number of segmental perfusion defects (0–18). Optional “Combined Score” adds clot-burden points (anatomic thrombus load) for stronger correlation with hemodynamics. 2) Perfusion Defect Percentage (Kim et al., 2014): Mean extent of perfusion defect across three coronal plane
Echocardiographic PH Probability Algorithm (TTE-based): Explanation and Clinical Context This calculator applies the 2022 ESC/ERS transthoracic echocardiographic algorithm for pulmonary hypertension (PH). It integrates the peak tricuspid regurgitation velocity (TRV) with secondary echocardiographic signs grouped into three categories (A, B, and C). A TRV > 3.4 m/s alone indicates a high probability of PH. When TRV is
Oxygen Desaturation Index (ODI): Explanation and Clinical Context Oxygen Desaturation Index (ODI) quantifies the number of oxygen desaturation events per hour of sleep, typically defined as a ≥4% drop in oxygen saturation from baseline, lasting at least 10 seconds. It serves as a non-invasive and practical surrogate for the Apnea–Hypopnea Index (AHI) in evaluating sleep-disordered breathing (SDB). An elevated ODI ref
Peak TRV Risk Stratification: Explanation and Clinical Context Peak tricuspid regurgitant velocity (TRV) is a key echocardiographic parameter used to estimate pulmonary artery systolic pressure (PASP) and assess the probability of pulmonary hypertension (PH). It is derived from continuous-wave Doppler measurement of the tricuspid regurgitation jet and incorporated into the simplified Bernoulli equation (ΔP = 4 × TRV²
Pulmonary Arterial Compliance Index (PACi): Explanation and Clinical Context Pulmonary arterial compliance reflects the pulsatile component of right ventricular afterload, calculated as stroke volume divided by pulmonary arterial pulse pressure (sPAP − dPAP). Indexing to body surface area yields the Pulmonary Arterial Compliance Index (PACi): SVI/(sPAP − dPAP), expressed in mL·m-2 per mmHg. Compliance represents the
Ascending Aorta (AA) diameter — same slice/level (mm) Sex (for sex-specific mPA normal limits) -- choose -- Male Female Pulmonary Artery Diameter Enlargement Ratio (CT-based): Explanation and Clinical Context The pulmonary artery–to–ascending aorta diameter ratio (PA/Ao) is obtained from axial chest CT at the level of the main pulmonary artery bifurcation, measuring the short-axis diameters of the main PA and ascendi
: Explanation and Clinical Context This calculator integrates non-invasive evidence to help differentiate pulmonary arterial hypertension (PAH) from PH due to left heart disease (PH-LHD). The H2FPEF score (Reddy et al., 2018) estimates HFpEF probability using atrial fibrillation (3), BMI >30 (2), ≥2 antihypertensives (1), age >60 (1), E/e' >9 (1), and PASP >35 (1). Scores ≥6 indicate a high likelihood of HFpEF, which
Pulmonary Vascular Resistance (PVR) Risk Tier: Explanation and Clinical Context Pulmonary Vascular Resistance (PVR) represents the afterload faced by the right ventricle and is calculated from the transpulmonary gradient (mean pulmonary artery pressure minus pulmonary artery wedge pressure) divided by cardiac output. It reflects the degree of obstruction within the pulmonary vasculature, primarily from remodeling or
Pulmonary Vasoreactivity Test Response Prediction Model: Explanation and Clinical Context This tool integrates a heuristic pre-test probability of a positive acute vasoreactivity test (AVT) response with established adult response criteria (Sitbon and Barst). Classic AVT response is defined by a ≥10 mmHg fall in mPAP to ≤40 mmHg without a drop in cardiac output (Sitbon), or ≥20% decrease in both mPAP and PVR with unc
REVEAL 2.0: Explanation and Clinical Context REVEAL 2.0 is a validated, weighted risk model for pulmonary arterial hypertension (PAH) that integrates demographics, hemodynamics, and biomarkers to estimate 1-year mortality. Each parameter contributes positive or negative points depending on risk direction. The final score stratifies patients into low (0–6), intermediate (7–8), and high (=9) risk. The calculator above
Stroke Volume Index (SVi) for RV Failure Prediction: Explanation and Clinical Context Stroke Volume Index (SVi) is a hemodynamic parameter that represents the stroke volume normalized to body surface area. It is calculated as cardiac output divided by heart rate and then indexed to BSA, providing a load-adjusted measure of cardiac performance. In the context of right ventricular (RV) failure prediction, SVi has been
Systolic Pressure Recovery Index (Post-Pulmonary Embolism Healing): Explanation and Clinical Context The Systolic Pressure Recovery Index (SPRI) is a hemodynamic ratio used to evaluate right ventricular and pulmonary arterial recovery after acute pulmonary embolism (PE). It quantifies the degree of pressure normalization across the pulmonary circulation, specifically reflecting how systolic and diastolic pressures re
TAPSE/PASP Optimization Index: Comprehensive Explanation and Clinical Context Definition & Formula: The TAPSE/PASP ratio (mm/mmHg) is a noninvasive surrogate of right ventricular-pulmonary arterial (RV-PA) coupling. It is calculated as tricuspid annular plane systolic excursion (TAPSE, in mm) divided by pulmonary artery systolic pressure (PASP, in mmHg). Measurement: TAPSE is measured by M-mode at the lateral tricusp