A novel survival model of cardioplegic arrest and cardiopulmonary bypass in rats: a methodology paper.
BACKGROUND
Given the growing population of cardiac surgery patients with impaired preoperative cardiac function and rapidly expanding surgical techniques, continued efforts to improve myocardial protection strategies are warranted. Prior research is mostly limited to either large animal models or ex vivo preparations. We developed a new in vivo survival model that combines administration of antegrade cardioplegia with endoaortic crossclamping during cardiopulmonary bypass (CPB) in the rat.


METHODS
Sprague-Dawley rats were cannulated for CPB (n = 10). With ultrasound guidance, a 3.5 mm balloon angioplasty catheter was positioned via the right common carotid artery with its tip proximal to the aortic valve. To initiate cardioplegic arrest, the balloon was inflated and cardioplegia solution injected. After 30 min of cardioplegic arrest, the balloon was deflated, ventilation resumed, and rats were weaned from CPB and recovered. To rule out any evidence of cerebral ischemia due to right carotid artery ligation, animals were neurologically tested on postoperative day 14, and their brains histologically assessed.


RESULTS
Thirty minutes of cardioplegic arrest was successfully established in all animals. Functional assessment revealed no neurologic deficits, and histology demonstrated no gross neuronal damage.


CONCLUSIONS
This novel small animal CPB model with cardioplegic arrest allows for both the study of myocardial ischemia-reperfusion injury as well as new cardioprotective strategies. Major advantages of this model include its overall feasibility and cost effectiveness. In future experiments long-term echocardiographic outcomes as well as enzymatic, genetic, and histologic characterization of myocardial injury can be assessed. In the field of myocardial protection, rodent models will be an important avenue of research.
de Lange
Fellery
F
Department of Anesthesiology, Duke University Medical Center, Durham, North Carolina, USA. flange@dds.nl
Yoshitani
Kenji
K
Podgoreanu
Mihai V
MV
Grocott
Hilary P
HP
Mackensen
G Burkhard
GB
D000818:Animals; D002315:Cardiopulmonary Bypass / Q000401:mortality*; D004195:Disease Models, Animal; D006324:Heart Arrest, Induced / Q000401:mortality*; D008297:Male; D008955:Models, Cardiovascular; D015428:Myocardial Reperfusion Injury / Q000401:mortality / Q000601:surgery*; D051381:Rats; D017207:Rats, Sprague-Dawley; D015996:Survival Rate