Nonthyroidal illness syndrome in off-pump coronary artery bypass surger

• Published in: Anatolian journal of cardiology 2015-10, Vol.15 (10), p.836-842
• Main Authors: Caluk, Selma, Caluk, Jasmin, Osmanovic, Enes
• Format: Article
• Language: English
• Subjects: Coronary Artery Bypass, Off-Pump - adverse effects; Euthyroid Sick Syndromes - blood; Euthyroid Sick Syndromes - etiology; Female; Humans; Male; Middle Aged; Prospective Studies; Risk Factors; Thyroid Hormones - blood
• ISSN: 2149-2271
• DOI: 10.5152/akd.2014.5732

It is well known that coronary artery bypass grafting (CABG) is often the cause of non-thyroidal illness syndrome (NTIS). Non-thyroidal illness syndrome (NTIS) is a state characterized by low levels of tri-iodo-thyronine (T3) and high levels of reverse T3 (rT3), with normal or low levels of thyroxin (T4) and normal, low-normal, or low levels of thyroid-stimulating hormone (TSH). Today, there are two main techniques of CABG: CABG with the use of cardiopulmonary bypass (on-pump coronary artery bypass - ONCAB) and CABG without the use of cardiopulmonary bypass (off-pump coronary artery bypass OPCAB), or 'beating-heart surgery.' The OPCAB technique is considered to be less invasive. We prospectively investigated the influence of these surgical techniques on the occurrence of NTIS. Serum levels of free fractions of thyroid hormones (FT3 and FT4) and TSH were analyzed in 70 consecutive patients subjected to CABG surgery, using the ONCAB technique in 36 patients and OPCAB technique in 34 patients. The measurements of hormone levels were performed prior to surgery and 12 hours and 14 days after surgery. The basic, the early, and the late postoperative serum levels of FT3 (p=0.458, p=0.632, p=0.869, respectively), FT4 (p=0.664, p=0.301, p=0.417, respectively), and TSH (p=0.249, p=0.058, p=0.324, respectively) were similar in both groups. The levels of FT3 and TSH were significantly lower 12 hours after surgery (p