hUniverse · Computational Cardiology Tools
From PDF to Practice
We are volunteers enthusiastic about increasing uptake of guidelines and building digital tools for medical education.
Scroll to see howMedicine’s best answers are already written.
Every guideline carries thousands of hours of expert judgment. Our work begins where theirs ends: making each recommendation as easy to reach as it was hard to write.
The gap
Rigorous guidelines. An uneven path to the patient.
A guideline is one of the most carefully built things in medicine: evidence weighed, recommendations argued, graded and cited. A document, however good, cannot carry a recommendation to the bedside by itself. Across cardiology, the distance between what is recommended and what reaches patients is still wide.
Fewer than 1 in 100
Outpatients with heart failure with reduced ejection fraction who were on target doses of all three foundational drug classes at once. Over a year of follow-up, only 6% to 10% had any given drug started or increased.
Source 1
Greene SJ, Fonarow GC, DeVore AD, et al. Titration of Medical Therapy for Heart Failure With Reduced Ejection Fraction. J Am Coll Cardiol 2019;73(19):2365-2383.
CHAMP-HF registry, 2,588 outpatients. Fewer than 1% were on target doses of all three classes. Over 12 months, initiation or a dose increase occurred in 6% to 10% by class.
4% to 60%
The range of SGLT2 inhibitor use in heart failure between cardiology practices, for a therapy recommended since 2021. Overall, fewer than 1 in 3 eligible patients had one by mid-2023. After accounting for the patients, a practice in the top tenth was more than five times as likely to prescribe one as a practice in the bottom tenth.
Source 2
El Rafei A, Gosch K, Manning ES, et al. Sodium-Glucose Cotransporter 2 Inhibitor Use for Heart Failure in US Ambulatory Cardiovascular Care. JAMA Cardiol 2025;10(9):904-913.
NCDR PINNACLE registry, July 2019 to June 2023. Practice-level use among patients with reduced ejection fraction ranged from 4% to 60% (median 22%). Adjusted odds ratio 5.53 for a practice at the 90th versus the 10th percentile.
1 in 2
Adults with established atherosclerotic cardiovascular disease who were on no statin at all, in a cohort of 601,934. Only 22.5% were on a high-intensity statin.
Source 3
Nelson AJ, Haynes K, Shambhu S, et al. High-Intensity Statin Use Among Patients With Atherosclerosis in the U.S. J Am Coll Cardiol 2022;79(18):1802-1813.
601,934 patients with established atherosclerotic cardiovascular disease: 22.5% on a high-intensity statin, 27.6% on a low or moderate intensity statin, 49.9% on no statin (claims snapshot, January 2019).
0.4%
Patients with atherosclerotic cardiovascular disease who had a lipoprotein(a) measured, among nearly 600,000 patients in five large US health systems.
Source 4
Shah NP, Mulder H, Lydon E, et al. Lipoprotein(a) Testing in Patients With Atherosclerotic Cardiovascular Disease in 5 Large US Health Systems. J Am Heart Assoc 2024;13(21):e035610.
595,684 patients with atherosclerotic cardiovascular disease, 2019 to 2021. 2,587 (0.4%) had a lipoprotein(a) test.
21%
US adults with hypertension whose blood pressure was controlled below 130/80.
Source 5
Hypertension Prevalence, Awareness, Treatment, and Control Among Adults Age 18 and Older: United States, August 2021 to August 2023. NCHS Data Brief No. 511, October 2024.
20.7% of adults with hypertension had blood pressure below 130/80; 59.2% were aware of the diagnosis and 51.2% were taking medication.
1 in 4
Eligible Medicare patients who took part in cardiac rehabilitation, against a national goal of 70%.
Source 6
Ritchey MD, et al. Tracking Cardiac Rehabilitation Participation and Completion Among Medicare Beneficiaries to Inform the Efforts of a National Initiative. Circ Cardiovasc Qual Outcomes 2020;13(1):e005902.
24.4% of 366,103 eligible beneficiaries participated. The Million Hearts goal was at least 70% by 2022.
A recommendation goes unused for many reasons. A landmark review of 76 studies catalogued 293 different barriers, from awareness and familiarity to agreement, confidence and habit. Cabana MD, et al. Why don’t physicians follow clinical practice guidelines? A framework for improvement. JAMA 1999;282(15):1458-1465. A review of 76 articles that identified 293 potential barriers to physician adherence to guidelines.Source 7
Some gaps have good clinical reasons, and some of these figures predate recent guideline updates. Even so, the size of the gaps, and the spread between practices that see similar patients, point to a delivery problem. The knowledge, the effort and the rigor are already there.
The evidence is there. The work is helping people reach it.
The idea
Same recommendations. A different way in.
Describe a patient. See what the guidelines say, which document says it, and why. The authority stays with the guideline. The tool is a faithful interface to it.
- 1Describe. A few clicks, in the language clinicians already use.
- 2Match. Each scenario is mapped in advance to the recommendations that apply.
- 3See the source. Every answer arrives with the guideline, and the table, it came from.
Patient
- Heart failure
- Reduced ejection fraction, LVEF 30%
- Kidney function
- eGFR 38 mL/min/1.73 m²
- Potassium
- 4.6 mmol/L
- Current medicines
- Beta-blocker, ACE inhibitor
Recommendations
Illustrative example, not a real patient.
Faithful to the source
Every answer shows its work.
We do not invent a number, and we do not write recommendations of our own. Each output is traced to a named guideline, trial or meta-analysis, down to the table, so a reader can verify it in one click and an author can see exactly how their work is represented.
Where a guideline is silent, or sources differ, the tool does not guess in secret. It shows the uncertainty, or says plainly that a logical inference is being made. It does not fill a gap with a made-up number, and it does not fail without telling you.
A tool is only as good as what is put into it, and we do not claim to out-think the clinician at the bedside. We make the evidence easier to apply alongside judgment.
If you wrote or reviewed a guideline and see something misrepresented, please tell us. We would rather be corrected than wrong.
The tools
13 tools, one standard.
AtheroPrevASCVD.org
Which recommendations in the 2026 ACC/AHA dyslipidemia guideline apply to this patient?
Enter the patient and see 10-year and 30-year PREVENT risk, LDL targets, and every recommendation that applies, each with its class, level of evidence, rationale and references.
Stressing WiselyStressingWisely.org
Which test for this patient with suspected or known chronic coronary disease?
Describe the patient and see ten tests and the choice of no test side by side, drawn from more than 400 clinical scenarios and over 5,000 ratings. Each is rated Appropriate, May Be Appropriate or Rarely Appropriate under the current appropriate use criteria, with contraindications alongside.
Table Manners: Pan with a PlanTableManners
How do I set the table and the C-arm to get this view?
Operate a simulated cath-lab table and C-arm in a 3D room, and watch the imaging geometry, radiation and a simulated fluoroscopy image respond together. Built for cardiology fellows and cath-lab technologists.
HeartGramHeartGram.org
Which angle shows this artery best?
Move a simulated C-arm to any angle and see how the coronary arteries appear on angiography, with foreshortening and overlap shown for each segment.
Troponin ToolboxTroponin.org
What does this troponin mean?
Classify a possible myocardial infarction under the Fifth Universal Definition, interpret serial high-sensitivity troponin values with likelihood ratios, and search all 103 recommendations of the 2025 ACC/AHA ACS guideline.
E/e'ureka: Echo ReadingEureka
What does this echocardiogram show, and how do I report it?
Work through an echocardiogram step by step and write the echo report. Built for cardiologists and cardiology fellows.
GDMT for EveryoneGDMT.org
What can I give at this stage of kidney function?
Step through heart failure therapy following the 2026 ESC heart failure guideline, and see what drug labels, guidelines and reviews say about each therapy at each stage of kidney function, quoted in their own words.
DecongesterDiurese.org
Why is the diuretic not working?
Check which segments of the nephron your medicines cover, convert between loop diuretics, judge whether diuresis is working and how congested a patient is, and learn the physiology behind each step.
SwanologySwanology.org
What do these right-heart catheterization numbers mean?
Enter the numbers and see derived hemodynamics with every formula shown, then learn to read the waveforms by walking a catheter from the right atrium to the wedge. Built for residents, fellows and advanced practice providers.
CardsOnc CO-PilotCardsOnc.org
What cardiac care does this patient on cancer therapy need?
Choose the cancer treatment, add cardiovascular history, risk factors and baseline heart function, and see the recommended cardiac assessment, following the 2022 ESC cardio-oncology guidelines.
CardioOB: Two Hearts, One MissionCardioOB.org
Look up the 2025 ESC guideline for cardiovascular disease and pregnancy: mWHO risk class, emergency algorithms, valve anticoagulation, hypertension and drug safety, with class and level always shown beside each recommendation.
Finding Hemo: Follow the FlowHemodynamics.org
Change the heart and circulation and watch pressures, flows and volumes respond. Guided lessons and cases, plus a full laboratory of pressure-volume loops, waveforms and measurements.
PQRSTudioMusicOfTheHeart
Can you hear a heartbeat?
Upload an ECG strip and hear it composed into music, in your choice of instruments, with the notation shown beside it. It is an artistic tool and is not meant for diagnosis.
And many more are on the way.
A tool takes anywhere from weeks to years to reach you. Along the way its logic is tested and tightened, round after round, and new features are added as the people who use it say what they need. We release a tool when it is ready, and it keeps improving afterwards.
Languages
Free to use. Increasingly in your language.
Some of our tools are offered in more than one language, and the languages differ from tool to tool:
- AtheroPrevEnglish, Spanish, French, Japanese, Chinese, Korean, Turkish, Thai
- CardsOnc CO-PilotEnglish, Spanish, Chinese, Japanese, Hindi, Marathi, French, Turkish
- Troponin Toolbox (teaching materials)Spanish, Portuguese, Arabic, Chinese, Korean, French, Turkish
Translations are done with volunteer translators. If your language is missing from a tool you use, tell us.
Across the family there are also light and dark themes, adjustable text size, and one consistent design that works on phones, so the experience is streamlined for you.
The scattered word is “Troponin” in the languages of its teaching materials.
The people
Volunteers who care whether guidelines reach patients.
No one is paid to build these tools. They are built by people who give their time because they are passionate about building useful tools and about helping guidelines reach the people they were written for.
- Attending cardiologists
- Community cardiologists
- Pharmacists
- Nephrologists
- Nurse practitioners
- Physician assistants
- Fellows
- Residents
- Medical students
- Postdoctoral researchers
Recognition
Recognized by
2025
Winner, KCVD Educational Tools Contest
American Heart Association
Council on Kidney in Cardiovascular Disease
For work on cardiorenal syndrome and diuretic resistance
Decongester
2023
National Quality Improvement Award
American Society of Nuclear Cardiology
For work in multimodality evaluation of ischemic heart disease
Stressing Wisely
2023
Faculty Educational Innovation Grant
Yale School of Medicine
Department of Internal Medicine
One of four awarded each year for innovative medical education projects, including education about myocardial injury and infarction
Troponin Toolbox
2022
Winner, KCVD Educational Tools Contest
American Heart Association
Council on Kidney in Cardiovascular Disease
For work promoting uptake of guideline-directed medical therapy in heart failure
GDMT for Everyone
Where this goes
Every guideline should arrive with a way to use it.
- Within days. New recommendations should become usable soon after they are published. We are working to shorten that wait.
- One home. One address, one design, one place to find the right tool.
- Wherever you practice. More tools in more languages, as volunteer translators join us.
- Toward better care. The hope is that easier access to guidelines means fewer unnecessary tests and more patients on the treatments recommended for them. That hope has not been tested yet. Testing it is the next chapter.
What question does your corner of cardiology keep asking?
Every subspecialty has a consult that never gets easier, the one that sends you back to a two-hundred-page document yet again. Somewhere in each there is a recommendation waiting to become a tool, and a clinician who knows exactly which one.
- Electrophysiology
- Imaging
- Heart failure
- Prevention
- Structural
- Congenital
- Cardio-oncology
- Cardio-obstetrics
- Vascular
Got a consult question that keeps coming back?
That is where every one of these tools started. If you have a decision that could be easier, a language you can translate into, or a guideline waiting to become a tool, let’s build it.
Write or review guidelines? We would be glad to hear from you: corrections, ideas for making recommendations easier to use, or collaboration.
For educational purposes only. These tools are not validated for clinical use. They do not provide medical advice and must not be used to diagnose, treat or make decisions about any patient. Content may be incomplete or out of date; verify against current guidelines and primary sources. The tools are independent educational resources and are not affiliated with, or endorsed by, the organizations that issue the guidelines they draw on.