Catheter-based transcoronary myocardial hypothermia attenuates arrhythmia and myocardial necrosis in pigs with acute myocardial infarction

J Am Coll Cardiol. 2007 Jan 16;49(2):250-60. doi: 10.1016/j.jacc.2006.06.080. Epub 2006 Dec 29.


Objectives: This study evaluated the efficacy of catheter-based transcoronary myocardial hypothermia (CTMH) in pigs with acute myocardial ischemia.

Background: Although it has been suggested that hypothermia therapy can attenuate myocardial necrosis, few applications have been accepted for clinical use.

Methods: This study comprises 2 substudies. In both studies, pigs underwent 60 min of coronary occlusion and 180 min of reperfusion. In study 1, after 15 min of coronary occlusion with an over-the-wire-type balloon (OTWB), pigs in the hypothermia group (H) (n = 13) were directly infused with 4 degrees C saline into the coronary artery through the OTWB wire lumen (2.5 ml/min) for 60 min. Pigs in the normothermia group (N) (n = 15) received the same amount of 36.5 degrees C saline. In study 2, pigs in the hypothermia-reperfusion group (HR) (n = 5) were infused with 4 degrees C saline through the infusion catheter (8 ml/min) for 30 min with a later start (60 min after coronary occlusion), whereas simple reperfusion was used for the reperfusion group (R) (n = 6).

Results: Catheter-based transcoronary myocardial hypothermia was successful in both studies. In study 1, CTMH significantly decreased ventricular arrhythmia and the ratio of necrosis to ischemic risk area (H: 9 +/- 2%; N: 36 +/- 4%; p < 0.0001) with a significant reduction of enzyme leaks. In study 2, CTMH tended to reduce the ratio of necrosis (HR: 33 +/- 2%; R: 45 +/- 5%; p = 0.08). In both studies, CTMH significantly suppressed the increase of 8-iso-prostaglandin F(2alpha) while preserving the coronary flow reserve.

Conclusions: Catheter-based transcoronary myocardial hypothermia reduced myocardial necrosis while preserving coronary flow reserve, due, in part, to attenuation of oxidative stress.

Publication types

  • Comparative Study

MeSH terms

  • Analysis of Variance
  • Animals
  • Arrhythmias, Cardiac / prevention & control*
  • Arrhythmias, Cardiac / therapy
  • Catheterization
  • Coronary Circulation / physiology
  • Disease Models, Animal
  • Female
  • Hypothermia, Induced / instrumentation
  • Hypothermia, Induced / methods*
  • Male
  • Myocardial Infarction / pathology*
  • Myocardial Infarction / therapy*
  • Myocardial Reperfusion Injury / prevention & control*
  • Myocardial Reperfusion Injury / therapy
  • Necrosis / pathology
  • Necrosis / prevention & control
  • Probability
  • Sensitivity and Specificity
  • Swine