With continuous low flow cardioplegia perfusion to maintain cardiac arrest, the
major vessels of the swine, canine, or human heart are cannulated while the excised heart remains in a
buffer slurry. The inferior vena cava, pulmonary artery, right and left superior pulmonary veins,
and aorta are fitted with clear tygon tubing and then connected to the isolated heart apparatus. In
addition, the superior vena cava and the innominate artery of the aorta are cannulated to serve as
camera ports for filming right and left side anatomy, respectively. After approximately 1-3 hours of
cardioplegia perfusion, the heart is reanimated with the flow of a oxygenated clear crystalloid
perfusate. The temperature of the perfusate is slowly increased over a 15-30 min. period until
cardiac temperatures raised to and maintained at 37.5±0.5°c. Initially, the heart is perfused
using the method of Langendorff as this provides the myocardium with the oxygen and metabolites that
have been depleted during the ischemic period. Once the heart is warmed, spontaneous electrical
activity returns. If normal atrioventrical electrical activity (i.e. sinus rhythm) is not present
upon reperfusion, a 10-34 Joule defibrillation shocks are delivered. This procedure is repeated
until normal sinus rhythm is observed. After 10 minutes of observed sinus rhythm with the absence of
severe arrhythmias, the apparatus can be modified so as to allow the heart to resume its intrinsic
functional activity in a 4 chamber working mode.
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