This calculator is for general information and education. It is not medical advice and does not replace the judgment of a doctor, nurse or pharmacist who knows the full clinical picture.
In 1967, Thomas Killip and John Kimball described 250 patients admitted to a coronary care unit with an acute myocardial infarction and sorted them by how much heart failure they showed on the first examination. The four groups had strikingly different outcomes, and the Killip classification is still recorded for every heart attack today. It takes a minute at the bedside, needs only a stethoscope and a blood pressure cuff, and feeds directly into the GRACE score.
The four classes
| Class | Findings | Hospital mortality in 1967 |
|---|---|---|
| I | No crackles, no S3 gallop | 6% |
| II | Crackles in the lower half of the lungs, S3 gallop or raised jugular venous pressure | 17% |
| III | Acute pulmonary edema: crackles over the whole lung fields | 38% |
| IV | Cardiogenic shock: systolic pressure under 90 mmHg with signs of poor perfusion | 81% |
The calculator asks the questions from the most severe down, as a clinician would: if there is shock, the patient is class IV whatever the lungs sound like; if not, pulmonary edema means class III, and so on.
Example
A 70-year-old man with an anterior infarction has fine crackles at both bases, no S3, a blood pressure of 118/70 mmHg and warm hands. He is Killip class II. In the GRACE score this adds 20 points.
Why the old mortality figures are higher than today
The 1967 figures come from an era before thrombolysis, primary angioplasty, beta-blockers, statins and modern intensive care. Mortality in every class is far lower now: in recent registries, in-hospital death is a few percent in class I and still around 30 to 50% in cardiogenic shock. What has not changed is the gradient. Each step up the classification multiplies the risk, which is why Killip class remains one of the strongest single predictors in modern risk scores.
How it is used
- Triage: class III and IV patients need intensive care, oxygen or ventilation, and urgent revascularization.
- Risk scores: Killip class is an input of the GRACE and TIMI STEMI scores.
- Follow-up: the class can change in the first hours; reassess after treatment and record the worst class.
Limits
Crackles can come from lung disease rather than the heart, and an S3 is easy to miss in a noisy room. Ultrasound of the lungs and the heart, and natriuretic peptides, help when the examination is doubtful.