Related Experiment Video
Updated: Aug 5, 2026
Surgical Swine Model of Chronic Cardiac Ischemia Treated by Off-Pump Coronary Artery Bypass Graft Surgery
Published on: March 27, 2018
Hemodynamic response to adenosine infusion before and after coronary artery bypass surgery
R E Anderson1, B Lind, A Owall
1Department of Cardiothoracic Anaesthetics and Intensive Care, Karolinska Hospital, Stockholm, Sweden.
Insights
Titrated adenosine infusions effectively assess myocardial ischemia after coronary artery bypass graft (CABG) surgery. Tolerance to adenosine is reduced early post-CABG, necessitating careful titration for pharmacologic stress testing.
Area of Science:
- Cardiology
- Pharmacology
- Cardiac Surgery
Background:
- Coronary artery bypass graft (CABG) surgery can alter myocardial function and response to pharmacologic agents.
- Adenosine infusion is used for pharmacologic stress testing to detect reversible myocardial ischemia.
Purpose of the Study:
- To characterize the hemodynamic dose-response of titrated, continuous adenosine infusion before and after CABG surgery.
- To evaluate the safety and efficacy of adenosine for detecting myocardial ischemia in the early and late postoperative periods.
Main Methods:
- Hemodynamic parameters (heart rate, blood pressure) and Doppler echocardiography were assessed during adenosine infusion.
- Adenosine infusion rates were titrated to patient tolerance before and at 1 hour, 1 week, and 1 year after CABG.
- Left ventricular function and outflow tract velocity were measured.
Main Results:
- Average tolerated adenosine infusion rates were lower at 1 hour and 1 week post-CABG compared to pre-surgery and 1 year post-CABG.
- Systolic blood pressure decreased significantly post-CABG with adenosine infusion.
- Outflow tract velocity integral increased post-CABG, indicating preserved or enhanced contractility.
Conclusions:
- Titrated adenosine infusion is suitable for pharmacologic stress testing in patients after CABG surgery.
- Fixed-rate adenosine protocols are not recommended for anesthetized or anemic patients in the early postoperative period.
- Adenosine's hemodynamic effects and dose-response characteristics change after CABG, requiring careful titration.
Abstract:
This study describes the hemodynamic dose-response characteristics of a titrated, continuous adenosine infusion before and 1 h (anesthetized), 1 week, and 1 year after coronary artery bypass graft (CABG) surgery. Average tolerated adenosine infusion rates were less 1 h and 1 week after surgery (128 +/- 23 and 118 +/- 27 microg/kg/min, respectively) than before (156 +/- 29 microg/kg/min) and 1 year after surgery (156 +/- 24 microg/kg/min). Heart rate (HR) increased with a 120-microg/kg/min adenosine infusion rate both preoperatively (21 +/- 11%) and 1 year postoperatively (16 +/- 8%). Systolic blood pressure (BP) decreased 26 +/- 11%, 14 +/- 7%, and 9 +/- 6% with 120 microg/kg/min adenosine for the three postoperative examinations. The integral of the outflow tract velocity with 120 microg/kg/min adenosine increased 49 +/- 22% and 29 +/- 12% after 1 h and 1 week, respectively, whereas its product with HR increased equally for all examinations (40 +/- 22%, 62 +/- 27%, 46 +/- 13%, and 39 +/- 11%). The average preoperative left ventricular area shortening was 45 +/- 10% and neither it nor end-diastolic left ventricular area (preload) changed with surgery, time after surgery, or with adenosine. A titrated adenosine infusion is well suited to patients requiring a pharmacologic provocation to expose reversible myocardial ischemia during the first hours or days after CABG surgery. The anesthetized and anemic patient are particularly unsuited for the commonly used fixed-infusion-rate protocol.
Related Concept Videos
01:29Pathophysiology of Cardiac Performance
01:28Cardiac Catheterization I: Pre-Procedure Overview
01:26Cardiac Catheterization IV: Nursing Management
01:25Cardiopulmonary Resuscitation IV: Pharmacological Management
01:28Cardiomyopathy VII: Pre and Post Operative Nursing Management