Why use it

Rapid bedside assessment requiring only physical exam. Strong predictor of in-hospital mortality after MI. Guides level of care: ICU vs. telemetry vs. CCU. Component of GRACE and other risk models.

About

The Killip classification stratifies patients with acute myocardial infarction based on clinical signs of heart failure at presentation. It predicts in-hospital mortality and guides the intensity of hemodynamic support and monitoring. Classes range from I (no heart failure) to IV (cardiogenic shock).

When to use

Acute myocardial infarction at presentation
Serial assessment of hemodynamic status during MI management
Component of GRACE risk score calculation

Formula

Class I: No clinical signs of heart failure Class II: Rales, S3, JVD Class III: Frank pulmonary edema Class IV: Cardiogenic shock (SBP < 90, signs of hypoperfusion)

Pearls & pitfalls

Killip class at presentation is one of the strongest predictors of MI mortality.
Class IV (cardiogenic shock) has ~50-80% mortality without revascularization.
Modern reperfusion therapy has improved outcomes across all Killip classes.
S3 gallop and JVD indicate Class II; rales in > 50% of lung fields indicate Class III.
Killip class can change during hospitalization — reassess serially.

Next steps

Class I: Standard MI management, telemetry. Class II: Diuretics, monitoring for deterioration. Class III: Aggressive diuresis, NIV, consider ICU/CCU. Class IV: Cardiogenic shock — vasopressors, inotropes, mechanical circulatory support, emergent cath.

Evidence

Original publication by Killip and Kimball (Am J Cardiol, 1967). Pre-reperfusion mortality: Class I ~6%, II ~17%, III ~38%, IV ~81%. Modern era with PCI: significantly lower but class remains prognostic.

References

Killip T, Kimball JT. Treatment of myocardial infarction in a coronary care unit. Am J Cardiol. 1967;20(4):457-464. — link

Killip Classification

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