Carrier M, Grégoire J, Khalil A, Thai P, Latour J G, Pelletier L C
Department of Surgery, Montreal Heart Institute, Quebec, Canada.
J Thorac Cardiovasc Surg. 1994 Dec;108(6):1115-8.
Perfusion of the right ventricular myocardium with retrograde infusion of cardioplegic solution through the coronary sinus has been reported to be less than optimal. To study left and right ventricular perfusion during retrograde and antegrade coronary sinus cardioplegia, we added 0.5 mCi of thallium 201 to 500 ml of hyperkaliemic crystalloid cardioplegic solution injected retrogradely into the coronary sinus at low perfusion pressure (20 to 40 mm Hg) in 14 dogs and antegradely in the ascending aorta in seven dogs. The cardioplegic solution was cold (4 degrees C) in eight animals perfused retrogradely and warm (21 degrees C) in 13 animals. After aortic crossclamping, the ascending aorta and the left and right ventricles were vented and cardioplegic solution was injected retrogradely into the coronary sinus. Antegrade injections were performed after aortic crossclamping and venting of the left and right ventricles and of the left and right atrium. After cardioplegic arrest, the heart was harvested, fixed, and scanned with a gamma camera. With cold retrograde cardioplegia, 82% +/- 5% of the injected thallium 201 activity was identified in the myocardium--71% +/- 9% for warm retrograde perfusion and 80% +/- 3% for antegrade perfusion (p > 0.05). Focal areas of hypoactivity in the septum and in the right ventricular free wall were present at scintigraphic imaging in all animals receiving retrograde perfusion. In conclusion, most thallium 201 activity of cardioplegic solution injected retrogradely in the coronary sinus was identified in the myocardium, but focal areas of hypoactivity in the septum and in the right ventricular free wall were present, indicating uneven distribution. Temperature of the crystalloid solution had no effect on the myocardial distribution of the thallium 201 radiotracer in the myocardium.
据报道，通过冠状窦逆行灌注心脏停搏液对右心室心肌的灌注效果欠佳。为了研究逆行和顺行冠状窦心脏停搏期间左、右心室的灌注情况，我们将0.5毫居里的铊201添加到500毫升高钾晶体心脏停搏液中，在14只狗中以低灌注压力（20至40毫米汞柱）逆行注入冠状窦，在7只狗中顺行注入升主动脉。在8只接受逆行灌注的动物中，心脏停搏液是冷的（4摄氏度），在13只动物中是温的（21摄氏度）。主动脉阻断后，升主动脉以及左、右心室进行排气，然后将心脏停搏液逆行注入冠状窦。在主动脉阻断以及左、右心室和左、右心房排气后进行顺行注射。心脏停搏后，取出心脏，固定，并用伽马相机扫描。对于冷逆行心脏停搏，在心肌中可识别出注入铊201活性的82%±5%——温逆行灌注为71%±9%，顺行灌注为80%±3%（p>0.05）。在所有接受逆行灌注的动物的闪烁显像中，室间隔和右心室游离壁均出现放射性减低的局灶区域。总之，逆行注入冠状窦的心脏停搏液中的大部分铊201活性在心肌中被识别出来，但室间隔和右心室游离壁存在放射性减低的局灶区域，表明分布不均匀。晶体溶液的温度对心肌中铊201放射性示踪剂的心肌分布没有影响。
