What Is a MACE Score and How Is It Calculated?

MACE stands for major adverse cardiac events, a shorthand doctors use for the serious outcomes they most want to prevent, such as a heart attack, a stroke, or death from heart disease. There is no single “MACE score.” The phrase usually points to one of several point-based tools (HEART, TIMI, GRACE, RCRI) that estimate how likely you are to have one of those events. They mostly rely on what is gathered in the first hours of care, like your age, a heart tracing and a blood test, so the number is a snapshot that helps guide decisions such as whether you can safely go home.

What Counts as a Major Heart Event

There is no standard definition of MACE, so the events counted vary from one study or tool to another.1PubMed. The problem with composite end points in cardiovascular studies: the story of major adverse cardiac events and percutaneous coronary intervention

The most common versions are:

Time span matters as much as the list. Emergency room chest-pain tools usually look at events in the next 30 days. Drug trials track events over years, to see whether a medicine is safe for the heart.

A bundle with more event types will usually show a higher percentage than a narrow one, simply because there are more ways to be counted. Comparing your number with someone else’s therefore only works if both use the same list of events. Every event in the bundle usually counts the same, even though a heart attack and death affect a life very differently.5TCTMD. MACE in CV Trials: Has the Outcome Outlived Its Role?

How the HEART Score Is Calculated

The HEART score is the chest-pain tool most people meet in the ER. It has five parts, each given 0, 1 or 2 points, and the points are added up to a total from 0 to 10:

The history part is a judgment call. The doctor weighs where the pain is, what brings it on and what eases it. Pain that comes with exertion and eases with rest scores higher. Sharp pain that changes when you press on the chest scores lower.

The risk-factor part is scored by how many of these conditions you have, so someone with several scores higher than someone with one. A history of established artery disease, such as a past heart attack or bypass surgery, is generally treated as the highest level. The doctor can only count what they know, so mentioning diabetes, family history, smoking and any blood-pressure or cholesterol medicines helps the score reflect you.

Here is how it might add up. A 50-year-old smoker with somewhat suspicious pain might get 1 for history. A normal ECG gives 0, and age 45 to 64 gives 1. One risk factor gives 1, and a normal troponin gives 0. That makes a total of 3.

Troponin is often tested twice. It can take hours to rise after heart damage, so a second test a few hours later shows whether the level is climbing.

Totals of 0 to 3 are generally treated as low risk, 4 to 6 as moderate and 7 to 10 as high. But one hospital found that people scoring exactly 3 had more heart events than expected.11PubMed Central. Elevated Major Adverse Cardiac Event (MACE) Risk With a HEART Score of 3: A Single-Site Retrospective Validation Study A 3 is a borderline result worth discussing before you leave.

What a Low Score Means for Going Home

In a trial, people managed with a HEART-based plan were twice as likely to go home early, about 40% versus 18%.12PubMed Central. The HEART Pathway Randomized Trial Their hospital stay was about 12 hours shorter, and fewer had extra heart tests within a month.13PubMed Central. The HEART Pathway Randomized Trial A larger trial found that using the HEART score was safe.14PubMed. Effect of Using the HEART Score in Patients With Chest Pain in the Emergency Department: A Stepped-Wedge, Cluster Randomized Trial Even so, doctors often still admit or test people with low scores, so the score doesn’t always change the plan.15PubMed. Effect of Using the HEART Score in Patients With Chest Pain in the Emergency Department: A Stepped-Wedge, Cluster Randomized Trial

A very low troponin level adds reassurance. With a normal ECG and symptoms starting at least 3 hours earlier, a very low level meant fewer than 2 in 100 people had a heart event within 30 days.16PubMed Central. Low High-Sensitivity Troponin Thresholds Identify Low-Risk Patients With Chest Pain Unlikely to Benefit From Further Risk Stratification The few who did were flagged by their doctor’s judgment as high risk.17PubMed Central. Low High-Sensitivity Troponin Thresholds Identify Low-Risk Patients With Chest Pain Unlikely to Benefit From Further Risk Stratification

Doctors also weigh the story of your pain, your exam and your test results, and they can overrule a low score. If your symptoms are still going on, or you live alone far from a hospital, they may choose a longer stay even with a low total.

“Low risk” means the chance of a serious heart event in the coming weeks is small. It does not mean your chest pain has been explained. The pain could still come from something else that needs attention, such as acid reflux, a muscle problem or anxiety, and the ER may or may not have looked for those.

Before you leave, ask what your total was and which parts scored. Ask whether a follow-up stress test or clinic visit is planned. Know which symptoms mean coming straight back, such as pain at rest or pain with breathlessness.

TIMI and GRACE Scores After a Heart Attack Diagnosis

TIMI and GRACE are mainly used once a heart attack or unstable angina has been diagnosed, to judge how risky the next weeks or months are. The HEART score, in contrast, is used earlier, to decide whether a heart attack is likely at all in someone with chest pain. If you see TIMI or GRACE on your report, it usually means doctors already believe your heart was affected.

TIMI gives one point for each of seven items:

Over the following two weeks, serious events rose from about 5% at a score of 0 or 1 to about 41% at 6 or 7.25PubMed. The TIMI risk score for unstable angina/non-ST elevation MI: A method for prognostication and therapeutic decision making

The aspirin point isn’t there because aspirin harms the heart. Having taken aspirin suggests known heart disease, or that symptoms broke through treatment, so it marks higher underlying risk.

GRACE works differently. It uses age, blood pressure, heart rate, a kidney blood test, cardiac arrest on arrival, heart blood markers, ECG changes and signs of heart failure.26PubMed Central. The prognostic utility of GRACE risk score in predictive adverse cardiovascular outcomes in patients with NSTEMI and multivessel disease Rather than simple counting, the values go into a calculator, and each measurement carries a different weight. The result is a percent chance of death, not just a category. It uses only admission values, not long-term illnesses or how blocked the arteries are.27PubMed Central. The prognostic utility of GRACE risk score in predictive adverse cardiovascular outcomes in patients with NSTEMI and multivessel disease It predicted death in hospital and over six months reasonably well, right about three times in four.28Int J Cardiovasc Sci. Validation of the Grace Risk Score to Predict In-Hospital and 6-Month Post-Discharge Mortality in Patients with Acute Coronary Syndrome

Heart Risk Scores Before Surgery

Before a non-heart operation, doctors often use the Revised Cardiac Risk Index (RCRI). It gives a point each for high-risk surgery, known heart disease, heart failure, past stroke, insulin-treated diabetes and poor kidney function. It is built into pre-surgery guidelines and sorted 30-day heart risk reasonably well in over 160,000 operations, in women and men.29Circulation Journal. Sex Differences in Post-Noncardiac Surgery Risks Assessed Using the Revised Cardiac Risk Index ― A Nationwide Retrospective Cohort Study ― People scoring 3 or more had far higher odds of heart complications.30PubMed Central. Assessing the accuracy of the revised Cardiac Risk Index compared to the American Society of Anaesthesiologists physical status classification in predicting Pulmonary and Cardiac complications among non-cardiothoracic surgery patients at Muhimbili National Hospital: a prospective cohort study

A low total suggests the heart is unlikely to be the main problem in surgery, while a higher one calls for more thought. Because it counts only a few items, it can miss details such as how well you manage everyday activity.

“High-risk surgery” in this index generally refers to big operations in the chest, abdomen or major blood vessels. A smaller procedure, such as a cataract operation or a skin surgery, does not add that point.

That is also why doctors often ask whether you can climb a couple of flights of stairs or walk briskly without chest pain or breathlessness. Being able to do so is a sign that your heart copes with effort, which can be reassuring alongside the score. If you can’t, it can lead to more testing, even when the RCRI total is low.

A high RCRI may lead to extra tests or steps before an operation, not automatically to cancellation.31PubMed Central. Prognostic Value of CT-Based Coronary Imaging for Perioperative Cardiovascular Risk Stratification Before Noncardiac Surgery: An Updated Systematic Review and Meta-Analysis Your surgeon and anesthetist may order a heart check or tests, adjust medicines before surgery, or monitor you more closely afterward. Bring a list of your heart conditions and medicines to the pre-op visit.

Blood Tests, Scans and Other Factors That Refine Risk

A coronary calcium score counts hardened plaque in the heart arteries on a CT scan. The scan takes a few minutes, uses no injected dye, and produces a single number. A score of zero means no calcified plaque was seen, which is reassuring, while higher numbers mean more plaque. It looks only at calcified plaque, so it doesn’t show softer plaque or how narrow an artery is.

A CT angiogram does use injected contrast dye, so the arteries themselves show up, revealing narrowing as well as plaque. In people with diabetes and no symptoms, an angiogram showing how many arteries were blocked predicted events better than calcium alone.32PubMed Central. Incremental prognostic value of coronary computed tomographic angiography over coronary artery calcium score for risk prediction of major adverse cardiac events in asymptomatic diabetic individuals That extra detail comes with dye and more radiation. Adding a calcium score to heart-scan results also improved prediction.33PubMed Central. Integration of coronary artery calcium scoring from CT attenuation scans by machine learning improves prediction of adverse cardiovascular events in patients undergoing SPECT/CT myocardial perfusion imaging

Calcium scans are generally considered for people without symptoms when their risk is unclear and the result could change decisions about treatment. They are not routine for everyone, and many people never need one. If you have chest pain, doctors usually choose tests suited to symptoms instead.

Blood markers can add information too. NT-proBNP, a blood test of heart strain, improved prediction in general-practice patients, while hs-CRP, an inflammation test, did not.34PubMed. Prognostic value of NT-pro-BNP and hs-CRP for risk stratification in primary care: results from the population-based DETECT study After a heart attack, though, using both together predicted outcomes better than NT-proBNP alone.35PubMed Central. Prognostic Value of N-Terminal Pro-B-Type Natriuretic Peptide and High-Sensitivity C-Reactive Protein in Patients With Previous Myocardial Infarction If your lab report lists NT-proBNP, a higher value means the heart is under more strain.

Kidney disease and diabetes raise risk as well. The risk of major heart events rose as kidney function fell, and was 2 to 5 times higher at each stage in people who also had type 2 diabetes.36PubMed Central. Major adverse cardiovascular events in people with chronic kidney disease in relation to disease severity and diabetes status Tell doctors about kidney problems and diabetes, since some scores don’t fully capture them.

How Accurate MACE Risk Scores Are

Common 10-year heart-risk calculators overestimated risk in a modern mixed-ethnicity group, by 8% up to 154% depending on the tool and sex.37PubMed Central. An Analysis of Calibration and Discrimination Among Multiple Cardiovascular Risk Scores in a Modern Multiethnic Cohort When a calculator overestimates, it predicts more events than actually happen in a group of similar people. A person told they are at high risk may therefore be at lower actual risk than the number suggests.

Scores built in one group may also fit another poorly. A score is developed using data from certain patients, often in certain places and times, and it works best for people like them. Treatments and lifestyles change, so a score built on older data may not reflect today’s patients. If you differ from the original group, such as in ethnicity or age, the estimate may be less accurate for you.

Computer models for predicting events after a heart attack correctly picked out about 78% of people who went on to have one.38PubMed Central. Accuracy of Machine Learning Models for Early Prediction of Major Cardiovascular Events Post Myocardial Infarction: A Systematic Review and Meta-Analysis Across larger patient groups, the best computer models were only moderately better than chance at predicting MACE.39PubMed. Comprehensive Machine Learning-Enabled Outcome Prediction for Patients With Coronary Artery Disease Using Multicentre Patient Data

A score is a probability, not a certainty. A 10% risk means 1 in 10 similar people have an event. Most people with a high score won’t have one, and some low scorers will. Useful questions to bring to your doctor: which score was used and what number did I get, over what time period does it apply, and what would lower my risk?