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Published on: March 27, 2018

Circadian rhythm has no effect on mortality in coronary artery bypass surgery

Ajay K Dhadwal1, Mikhail Vaynblat, Shyama Balasubramanya

  • 1Maimonides Medical Center, Brooklyn, New York, New York 11219, USA.

Journal of Cardiac Surgery
|January 24, 2007
PubMed

Insights

Circadian variation does not impact mortality for non-emergency coronary artery bypass graft (CABG) surgery. Emergency CABG patients showed increased mortality when surgery occurred in the morning or at night compared to the afternoon.

Area of Science:

  • Cardiovascular Surgery
  • Circadian Biology
  • Surgical Outcomes Research

Background:

  • Circadian variation's impact on atherosclerosis is understudied in surgical patients.
  • This study investigates circadian variation in mortality related to the timing of coronary artery bypass graft (CABG) surgery.

Purpose of the Study:

  • To examine the relationship between the time of day surgery is performed and 30-day mortality in CABG patients.
  • To determine if circadian variations influence outcomes in cardiac surgical procedures.

Main Methods:

  • Retrospective review of 3140 CABG patients (1999-2002).
  • Patients categorized into elective, urgent, and emergency groups.
  • Operations classified by start time: morning (7 AM-2 PM), afternoon (2 PM-8 PM), and night (8 PM-7 AM).
  • Mortality compared across time frames; risk factors and anastomoses analyzed.

Main Results:

  • No significant difference in mortality for elective or urgent CABG based on surgery timing.
  • Emergency CABG cases showed significantly higher mortality in morning and night surgeries compared to afternoon (p < 0.01 and p < 0.05).
  • No significant differences in age, gender, anastomoses, ejection fraction, or preoperative risk factors between groups.

Conclusions:

  • Mortality for non-emergent CABG procedures is independent of surgical timing.
  • Circadian variation does not appear to influence outcomes in cardiac surgical patients.
Abstract

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