Clinical Calculators
105 validated calculators and decision aids for cardiology and electrophysiology — organized by clinical domain with linked guidelines and references.
General Clinical
Renal Function
Creatinine Clearance
Cockcroft-Gault equation — critical for anticoagulant and antiarrhythmic drug dosing. Uses actual and ideal body weight with obese adjustment.
OpeneGFR (CKD-EPI)
2021 CKD-EPI Creatinine Equation — estimates glomerular filtration rate and CKD stage. Preferred for CKD classification and drug dosing.
Open NewMDRD eGFR
4-variable MDRD Study equation — widely used for GFR estimation in research and clinical practice, with CKD stage classification.
Open NewContrast Nephropathy Risk
Mehran Score for contrast-induced nephropathy risk after PCI — stratifies risk using 8 variables including baseline renal function and hemodynamics.
OpenBody Metrics & Dosing
Ideal Body Weight
Devine formula for IBW plus adjusted body weight for obese patients — used in drug dosing, ventilator tidal volume, and CrCl calculations.
OpenBody Surface Area / Indexed Valve Area
Dubois and Mosteller BSA formulas with indexed valve area calculations — essential for interpreting echo parameters in small and large patients.
OpenElectrolytes & Metabolic
Corrected Calcium
Albumin-adjusted calcium (Payne formula) with ionized calcium estimate, clinical classification, and ECG correlations for hypo- and hypercalcemia.
Open NewAnion Gap
AG, albumin-corrected AG, delta-delta ratio, and osmolar gap — complete acid-base assessment with MUDPILES differential and toxic alcohol screening.
OpenHyperkalemia ECG Risk
Clinical and ECG severity assessment in hyperkalemia — correlates serum K⁺ with ECG manifestations and provides immediate management guidance.
OpenHemodynamic Basics
Mean Arterial Pressure
MAP, pulse pressure, and hemodynamic assessment — includes cerebral perfusion pressure calculation and organ perfusion interpretation.
OpenShock Index & REMS
Shock Index (HR/SBP), Reverse SI, Modified SI, and REMS score — rapid hemodynamic instability assessment with in-hospital mortality prediction.
OpenQTc Correction
Calculate QTc using five validated formulas: Bazett, Fridericia, Framingham, Hodges, and Rautaharju — includes adjustment for wide QRS morphology.
OpenCritical Care / Shock
SCAI Shock Classification
Society for Cardiovascular Angiography & Interventions cardiogenic shock staging (A–E) — standardized classification guiding escalation, MCS selection, and prognostication.
Open NewSOFA Score
Sequential Organ Failure Assessment — scores 6 organ systems (respiratory, coagulation, liver, cardiovascular, CNS, renal) for ICU mortality prediction and sepsis diagnosis.
OpenPrevention / Risk
ASCVD 10-Year Risk
ACC/AHA Pooled Cohort Equations — 10-year risk of a first atherosclerotic cardiovascular event. Primary tool guiding statin therapy decisions.
Open NewFramingham Risk Score
Classic 10-year coronary heart disease risk model from the Framingham Heart Study — integrates age, cholesterol, BP, smoking, and diabetes.
Open NewMESA Risk Score
MESA 10-year CHD risk score with optional coronary artery calcium integration — reclassifies intermediate-risk patients and guides statin initiation.
Open NewLifetime ASCVD Risk
Lifetime cardiovascular risk estimation from the Framingham Offspring and Multi-Ethnic cohorts — motivates prevention in younger patients with low 10-year risk.
Open NewCardiovascular Age
Estimated cardiovascular age based on risk factor burden — compares patient's vascular age to chronological age to communicate prevention urgency.
Open NewLDL Reduction / Statin Intensity
Expected LDL-C reduction for statin intensity classes — calculates target LDL and helps select appropriate statin dose per ACC/AHA guidelines.
Open NewAHA PREVENT Calculator
2023 AHA PREVENT equations — 10- and 30-year CVD risk incorporating eGFR, HbA1c, and UACR. Replaces Pooled Cohort Equations as the guideline-recommended tool.
Open NewSCORE2 / SCORE2-OP
ESC 2021 Systematic Coronary Risk Evaluation — 10-year fatal and non-fatal CVD risk calibrated by European region. SCORE2-OP extends to ages 70–89.
Open NewLp(a)-Adjusted ASCVD Risk
Lipoprotein(a)-enhanced cardiovascular risk estimation — adjusts baseline ASCVD risk for elevated Lp(a) levels, informing emerging targeted therapies.
Open NewSCORE2-OP (Ages ≥70)
ESC 10-year cardiovascular risk calculator for older persons — adapts SCORE2 for ages ≥70 with competing-risk methodology accounting for non-CV mortality.
OpenAcute Cardiology
Acute Coronary Syndromes
HEART Score
5-component risk score for chest pain triage — stratifies 6-week MACE risk to guide discharge vs. admission decision in the emergency department.
OpenTIMI Risk Score UA/NSTEMI
7-point checklist predicting 14-day risk of death, MI, or urgent revascularization — guides early invasive vs. conservative management strategy.
Open NewGRACE 2.0 ACS Risk
Global Registry of Acute Coronary Events — in-hospital and 6-month post-discharge mortality prediction for ACS patients, validated in 100,000+ patients.
Open NewGRACE In-Hospital Mortality
GRACE score for predicting in-hospital mortality in acute MI — stratifies low, intermediate, and high risk to support triage and invasive strategy timing.
OpenWellens' Warning
ECG recognition of Wellens' syndrome — critical proximal LAD stenosis presenting with characteristic T-wave patterns in V2-V3 during the pain-free state.
OpenPulmonary Embolism
Wells PE Score
Clinical pre-test probability for pulmonary embolism — dichotomized and three-tier scoring. Guides CT-PA vs. D-dimer decision in suspected PE.
Open NewRevised Geneva Score
Fully objective PE pre-test probability score — all variables are clinical or lab-based (no physician gestalt), validated in the PROPER multicenter study.
Open NewPESI & sPESI
Pulmonary Embolism Severity Index — original and simplified versions stratifying 30-day all-cause mortality risk to guide outpatient vs. inpatient management.
OpenHeart Failure
Prognosis & Risk
Seattle Heart Failure Model
1-, 2-, and 3-year mortality prediction in heart failure from the validated Levy 2006 model — integrates medications, labs, and hemodynamics.
OpenMAGGIC HF Mortality Score
3-year all-cause mortality risk in heart failure using the MAGGIC integer score — validated in 39,372 patients across 30 studies (Pocock 2013).
OpenHF Hospitalization Risk
1-year heart failure hospitalization risk in ambulatory HF patients — based on simplified CHARM risk factors including NYHA class and prior hospitalization.
Open NewH₂FPEF Score
Probability of HFpEF in patients with unexplained exertional dyspnea — 6-variable score from the Mayo Clinic, validated against PCWP measurements.
Open NewHFA-PEFF Score
ESC HFA diagnostic algorithm for HFpEF — stepwise scoring using functional, morphological, and biomarker criteria with invasive confirmatory step.
Open NewCardiac Power Output
CO × MAP integration — the strongest hemodynamic predictor of in-hospital mortality in cardiogenic shock. Guides MCS device selection and escalation.
Open NewRV Stroke Work Index
RV mechanical efficiency from right heart cath data — predicts RV failure risk after LVAD implant and guides perioperative management in advanced HF.
Open NewINTERMACS Profile
Interagency Registry for Mechanically Assisted Circulatory Support profiles 1–7 — classifies advanced HF severity to guide LVAD timing and transplant candidacy.
Open NewMELD-XI Score
Modified MELD excluding INR — assesses hepato-renal dysfunction in advanced HF patients on anticoagulation. Predicts outcomes in LVAD and transplant candidates.
OpenTreatment Guidance
GDMT Optimization Checklist
Guideline-directed medical therapy assessment for HFrEF — ARNI, beta-blocker, MRA, and SGLT2i status with optimization recommendations (AHA/ACC 2022).
OpenCRT Candidate Evaluation
CRT-D vs CRT-P vs ICD-only decision support — applies ACC/AHA/ESC 2021 guidelines with LBBB morphology, QRS duration, NYHA, and rhythm as inputs.
OpenCRT Response Probability
Guideline-based CRT response predictor — integrates LBBB morphology, QRS duration, LVEF, NYHA class, sex, and etiology (ESC 2021).
OpenICD Primary Prevention Benefit
AHA/ACC 2017 guideline-based ICD indication assessment for ischemic and non-ischemic cardiomyopathy — stratifies by LVEF, NYHA, etiology, and OMT status.
OpenPacemaker Dependency Estimator
Assess pacemaker dependency level for procedural planning — classifies High/Moderate/Low dependency with backup pacing recommendations.
OpenArrhythmias / Electrophysiology
Anticoagulation (AF)
CHA₂DS₂-VASc Score
Ischemic stroke risk stratification for atrial fibrillation — annual stroke/TE rate with anticoagulation recommendation per ACC/AHA 2023 guidelines.
OpenHAS-BLED Score
Major bleeding risk on anticoagulation — use alongside CHA₂DS₂-VASc for net clinical benefit assessment. Identifies modifiable bleeding risk factors.
OpenORBIT Bleeding Risk Score
5-factor major bleeding risk in AF patients on OAC — validated alternative to HAS-BLED with simpler variables (O'Brien 2015, ORBIT-AF registry).
OpenSAMe-TT₂R₂ Score
Predicts likelihood of achieving good anticoagulation control (high TTR) on warfarin in AF — guides DOAC vs. warfarin agent selection.
Open NewATRIA Bleeding Score
Anticoagulation and Risk Factors in Atrial Fibrillation — major hemorrhage risk score from the Kaiser Permanente ATRIA registry (Go 2003).
Open NewGARFIELD-AF Risk Tool
Global GARFIELD-AF registry risk tool — simultaneously estimates 1-year stroke/SE and bleeding risk in newly diagnosed non-valvular AF patients.
OpenAF Net Clinical Benefit
Net clinical benefit of anticoagulation in AF — weighs CHA₂DS₂-VASc stroke risk against HAS-BLED bleeding risk using validated adjustment factors.
Open NewEHRA AF Symptom Score
European Heart Rhythm Association AF symptom classification (I–IV) — standardized grading of AF-related symptoms to guide rhythm vs. rate control strategy.
Open NewCHARGE-AF Risk Score
Cohorts for Heart and Aging Research in Genomic Epidemiology — predicts 5-year new-onset AF risk using clinical variables for screening and prevention decisions.
Open NewDOAC Renal Dosing Guide
Auto-calculated CrCl with drug-specific dose selection for all 4 DOACs — apixaban, rivaroxaban, dabigatran, edoxaban across AF, VTE, and prophylaxis indications.
Open NewWarfarin Dose Adjustment
INR-based warfarin dose adjustment guide — covers subtherapeutic to supratherapeutic ranges, vitamin K reversal, 4-factor PCC dosing, and emergency protocols.
OpenQTc / Electrolytes
QTc Formula Comparison
Side-by-side comparison of Bazett, Fridericia, Framingham, and Hodges formulas — highlights formula disagreement at high or low heart rates.
OpenLong QT Schwartz Score
Diagnostic probability for congenital Long QT Syndrome — integrates QTc, ECG findings, clinical history, syncope, and family history (Schwartz criteria).
OpenDrug QTc Safety Check
Searchable reference of 50+ QT-prolonging medications — risk categories (Known / Possible / Conditional) and QTc stop thresholds per CredibleMeds.
OpenEP Arrhythmia Algorithms
Brugada Criteria for WCT
Modified Brugada 4-step algorithm — differentiates ventricular tachycardia from SVT with aberrant conduction using morphology and concordance criteria.
OpenVereckei aVR Algorithm
4-step sequential algorithm using only lead aVR to differentiate wide complex tachycardia — VT vs SVT with aberrancy (Vereckei 2008).
OpenSVT Differential Diagnosis
Step-by-step narrow complex tachycardia algorithm — distinguishes sinus tach, AVNRT, AVRT, AT, flutter, and AF using RP interval and clinical features.
OpenWPW AP Localization
Simplified algorithm for accessory pathway localization in WPW syndrome — uses delta wave polarity and QRS transition across leads.
OpenAtrial Tachycardia Localization
P-wave morphology algorithm to localize AT origin — crista terminalis, tricuspid annulus, pulmonary veins, coronary sinus, and other structures.
OpenIdiopathic VT Origin
Anatomic origin of idiopathic ventricular arrhythmias using QRS axis, transition, and morphology — RVOT, LVOT, fascicular, and other locations.
OpenVT Origin Predictor
Differentiate outflow tract (RVOT/LVOT), fascicular, and scar-mediated VT using QRS morphology, axis, precordial transition, and clinical history.
OpenIschemic VT Reentry Circuit
Pacing-based algorithm to identify VT reentry circuit location — entrainment maneuvers, concealed vs. overt fusion, and PPI-TCL interpretation.
OpenPVC Burden & CMP Risk
PVC-induced cardiomyopathy risk assessment using PVC burden, LVEF, QRS duration, and clinical risk factors. Guides monitoring and ablation decisions.
OpenDevice & EP Risk
HCM Risk-SCD
ESC formula for 5-year sudden cardiac death risk in hypertrophic cardiomyopathy — guides ICD implantation decisions (ESC 2014/2020 HCM guidelines).
OpenARVC/D Diagnostic Criteria
2010 Revised Task Force Criteria — stratifies findings into Definite, Borderline, or Possible ARVC/D across 6 diagnostic categories.
Open NewAF Ablation Risk (APPLE)
APPLE Score predicting AF recurrence after pulmonary vein isolation — pre-procedural risk stratification to guide ablation candidate selection and counseling.
Open NewBrugada Risk Score (Shanghai)
Shanghai Score for risk stratification in Brugada syndrome — integrates ECG, clinical history, family history, and genetic testing for ICD decision support.
Open NewPOAF Score
Post-Operative Atrial Fibrillation prediction after cardiac surgery — integrates age, COPD, GFR, LA size, and procedure type for prophylaxis and monitoring decisions.
Open NewPADIT Infection Risk
Predicts CIED pocket infection and endocarditis risk — guides pre-implant antibiotic prophylaxis intensity and post-procedural monitoring strategy.
Open NewMADIT-ICD Benefit Score
Refined ICD primary prevention benefit estimation beyond standard LVEF criteria — identifies patients most and least likely to benefit from prophylactic ICD therapy.
OpenInterventional Cardiology
Lesion Complexity & Revascularization
SYNTAX Score
Angiographic CAD complexity scoring — predicts PCI outcomes and guides PCI vs. CABG revascularization strategy in multivessel and LM disease.
Open NewResidual SYNTAX Score
Post-PCI residual SYNTAX scoring — quantifies completeness of revascularization. Residual score ≥8 predicts worse outcomes and may favor CABG referral.
OpenDAPT Duration & Bleeding Risk
DAPT Score
Ischemic vs. bleeding benefit of prolonged DAPT after drug-eluting stent — 9-variable score from the DAPT trial guides 12 vs. 30-month therapy duration.
Open NewPRECISE-DAPT Score
5-variable pre-PCI bleeding risk score — stratifies patients into short (3–6 months) vs. standard/long (12–24 months) DAPT duration after DES implantation.
Open NewARC-HBR Bleeding Risk
Academic Research Consortium High Bleeding Risk criteria — major and minor criteria for pre-PCI HBR classification guiding device selection and DAPT strategy.
OpenStructural / Valve Disease
Surgical & Procedural Risk
TAVR Risk Estimator
STS-PROM surgical risk estimation for aortic valve disease — TAVR vs. SAVR decision support per ACC/AHA 2020 valvular heart disease guidelines.
Open NewEuroSCORE II
European System for Cardiac Operative Risk Evaluation — in-hospital surgical mortality prediction for adult cardiac surgery. Successor to logistic EuroSCORE.
Open NewSTS Risk Calculator
Society of Thoracic Surgeons predicted risk of mortality — simplified bedside estimate for CABG and valve surgery operative mortality assessment.
OpenValve Severity Assessment
Aortic Stenosis Severity
AS grading by AHA/ACC and ESC criteria — AVA via continuity equation, DVI, and identification of low-flow/low-gradient patterns with paradoxical LFLG.
Open NewMitral Valve Area (PHT)
Mitral stenosis severity by pressure half-time method — MVA calculation using empiric formula (220/PHT). Includes PMVR candidacy assessment notes.
Open NewProjected AVA
Flow-corrected projected aortic valve area at normal flow — distinguishes true severe AS from pseudo-severe AS in low-flow low-gradient presentations.
OpenIndexed Valve Area
Body surface area indexing for aortic and mitral valve areas — essential for accurate severity grading in small patients (BSA <1.6 m²).
Open NewGorlin Formula
Invasive hemodynamic valve area calculation from cardiac catheterization data — uses transvalvular gradient, cardiac output, and flow period for aortic and mitral valves.
Open NewHakki Simplified Valve Formula
Quick cath lab valve area estimation — CO / √(peak gradient) approximation for aortic valve area when HR is 60–100 bpm. Validated against full Gorlin equation.
Open NewAVC Calcium Score for AS
Sex-specific aortic valve calcium thresholds for AS severity in low-flow low-gradient presentations — guideline-recommended CT calcium scoring for confirming severe AS.
OpenCardiac Imaging
Echocardiography
Stroke Volume / LVOT VTI
SV, SVi, CO, and CI from LVOT echo method — includes thermodilution and Fick data entry, with normal value reference and low-output interpretation.
OpenCardiac Index
CO indexed to BSA with stroke volume, SVi, and SVR calculations — accepts thermodilution, Fick, or echo data with hemodynamic state classification.
Open NewLV Mass Index
LV mass by ASE cube formula and Penn convention — indexed to BSA and height²·⁷ for LVH diagnosis and concentric vs. eccentric geometry classification.
Open NewRelative Wall Thickness
LV geometry classification — concentric hypertrophy vs. eccentric hypertrophy vs. concentric remodeling using posterior wall thickness and LVEDD.
Open NewLeft Atrial Volume Index
Biplane area-length and bullet method LA volume indexed to BSA — ASE/EACVI grading for mild, moderate, and severe LA enlargement.
Open NewE/e′ Filling Pressure
Non-invasive LV filling pressure estimation using mitral inflow E wave and tissue Doppler e′ — ASE/EACVI 2016 diastolic dysfunction algorithm.
Open NewTAPSE/PASP Ratio
RV-PA coupling index — TAPSE/PASP ratio below 0.36 mm/mmHg indicates uncoupled RV and is a powerful predictor of outcomes in pulmonary hypertension and HF.
OpenHemodynamics (Cath Lab)
Cardiac Output (Fick)
Direct Fick method — CO from VO₂, arterial/venous O₂ saturation, and hemoglobin. Includes estimated VO₂ option for right heart catheterization.
OpenPulmonary Vascular Resistance
PVR in Wood units and dyn·s/cm⁵ from right heart cath data — ESC 2022 pulmonary hypertension classification and transplant/MCS eligibility notes.
OpenCardiac Power Output
Strongest hemodynamic predictor of in-hospital mortality in cardiogenic shock — CO × MAP integration with MCS device selection guidance.
Open NewPulmonary Artery Pulsatility Index
PAPi = (PA systolic − PA diastolic) / RAP — predicts RV failure after LVAD and cardiac surgery. Threshold <1.0 indicates high-risk RV dysfunction.
OpenRV Stroke Work Index
RV mechanical efficiency from right heart cath data — predicts RV failure risk after LVAD implant and perioperative RV support need in advanced HF.
Open NewQp:Qs Shunt Calculator
Pulmonary to systemic blood flow ratio via oximetry (Fick) or Doppler echo — evaluates shunt significance in ASD, VSD, and PDA for intervention decisions.
OpenDisclaimer: All calculators and algorithms are validated clinical decision-support tools intended for use by licensed healthcare professionals. Results must be interpreted in the full clinical context of the individual patient. These tools support — but do not substitute — professional medical judgment. Full disclaimer →