Mehran CIN Risk Score

Predicts risk of contrast-induced acute kidney injury (CI-AKI) after percutaneous coronary intervention

Hypotension SBP <80 mmHg for ≥1 hr requiring IABP or vasopressors within 24h of procedure

Intra-aortic balloon pump IABP use during or after procedure

Congestive heart failure NYHA class III–IV and/or history of pulmonary edema

Age >75 years

Anemia Baseline Hct <39% (men) or <36% (women)

Diabetes mellitus

Contrast Media Volume

1 point per 100 mL (rounded down)

Renal Function (choose one)

Serum Creatinine >1.5 Use eGFR Neither / Normal

eGFR

mL/min/1.73m²

If eGFR <60: 2 points per 10 mL/min below 60 (max 12 points for eGFR <20)

Total Mehran Score 0

Contrast Volume Points 0

Renal Points 0

Risk of CIN ~7.5%

Risk of Dialysis ~0.04%

Risk Category Low Risk

CIN defined as increase in serum Cr ≥0.5 mg/dL or ≥25% increase from baseline within 48h after contrast exposure.

Score	Risk Category	CIN Risk	Dialysis Risk
≤5	Low	~7.5%	~0.04%
6–10	Moderate	~14%	~0.12%
11–15	High	~26%	~1.09%
≥16	Very High	~57.3%	~12.6%

CIN definition: Increase in serum creatinine ≥0.5 mg/dL or ≥25% from baseline within 48 hours of contrast exposure.
Consider N-acetylcysteine, IV hydration (isotonic saline or sodium bicarbonate), and minimizing contrast volume in high-risk patients.
Renal scoring: Scr >1.5 mg/dL = 4 points. If using eGFR: 2 points per 10 mL/min below 60 (e.g., eGFR 40 = 4 pts, eGFR 20 = 8 pts).