Effect of Preoperative Creatinine Levels on Mortality after Coronary Artery Bypass Grafting Surgery: an Observational...

Area of Science:

• Cardiology
• Nephrology
• Surgical Outcomes

Background:

• Renal function is a critical predictor of mortality in patients undergoing on-pump coronary artery bypass grafting (ONCABG).
• Limited understanding exists on how admission creatinine (AC) levels specifically influence cardiovascular risk factors in this population.

Purpose of the Study:

• To investigate the impact of varying admission creatinine levels on mortality rates among ONCABG patients.
• To analyze the association between different AC strata and specific cardiovascular risk factors.

Main Methods:

• A retrospective analysis of 1,599 patients who underwent ONCABG between 1999 and 2006.
• Patients were categorized into four quartiles based on admission creatinine levels (QI: 0.2–0.99 mg/dL, QII: 1.0–1.19 mg/dL, QIII: 1.2–1.39 mg/dL, QIV: ≥1.4 mg/dL).
• Seven cardiovascular risk factors were assessed within each AC quartile.

Main Results:

• Mortality rates were significantly higher in the highest creatinine quartile (QIV) compared to lower quartiles (QI, QII).
• Factors like advanced age (≥65 years), prolonged cardiopulmonary bypass time (≥115 minutes), and preoperative hospital stay (≥5 days) were linked to increased mortality in higher AC groups.
• A creatinine variation of ≥0.4 mg/dL, use of intra-aortic balloon pump, dialysis, and Type I neurological dysfunction were associated with increased mortality, with variations depending on the AC quartile.

Conclusions:

• Admission creatinine levels are a crucial determinant of mortality following ONCABG.
• The combination of elevated AC levels and other cardiovascular risk factors portends a poorer prognosis.
• Lower AC levels demonstrate a protective effect, even in high-risk patient subgroups such as the elderly or those with extended CPB times.