Urinary Titin Is Increased in Patients After Cardiac Surgery

Area of Science:

• Cardiology
• Biomarker Discovery
• Proteomics

Background:

• Limited non-invasive biomarkers exist for myocardial injury in heart disease.
• N-terminal fragment (N-titin) of titin, a giant sarcomeric protein, is implicated in muscle damage detection.
• Previous studies show N-titin detects muscle damage in cardiomyopathy, muscular dystrophy, and exercise.

Purpose of the Study:

• To evaluate perioperative changes in urinary N-titin levels.
• To determine if increased urinary N-titin reflects myocardial damage post-cardiac surgery.

Main Methods:

• Collected blood and urine samples from 18 cardiac surgery patients pre- and post-operatively.
• Quantified urinary N-titin levels using a sensitive ELISA system.
• Measured urinary N-titin to creatinine (N-titin/Cr) ratio.

Main Results:

• Urinary N-titin/Cr significantly increased post-surgery and remained elevated for at least 4 days.
• Urinary N-titin/Cr positively correlated with serum cardiac troponin T (r=0.36, p=0.0006).
• Coronary artery bypass grafting patients showed higher urinary N-titin/Cr by day 2 compared to other open cardiac surgeries.

Conclusions:

• Cleaved N-titin significantly increases in urine following cardiac surgery.
• Urinary N-titin shows potential as a biomarker for detecting latent postoperative cardiac damage.
• This non-invasive marker could aid in monitoring cardiac health after surgery.