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Fig. 11.3A. Explantation of the native heart. A. Initial incision is made in the right atrium close to the AV groove. B. Right atrial cuff completed down to the septum. C. Aorta and pulmonary artery transected, roof of the left atrium entered. D. With heart elevated, lateral left atrial cuff developed; pulmonary veins can be seen. E. As viewed from above, incision completed along AV groove. F. Final appearance—SVC and IVC entering RA cuff; pulmonary veins entering LA cuff.

Fig. 11.3A. Explantation of the native heart. A. Initial incision is made in the right atrium close to the AV groove. B. Right atrial cuff completed down to the septum. C. Aorta and pulmonary artery transected, roof of the left atrium entered. D. With heart elevated, lateral left atrial cuff developed; pulmonary veins can be seen. E. As viewed from above, incision completed along AV groove. F. Final appearance—SVC and IVC entering RA cuff; pulmonary veins entering LA cuff.

vented cardioplegia cannula is placed proximal to the suture line to allow evacuation of air and delivery of cardioplegia if necessary. If the ischemic time has been prolonged at this point the cross-clamp can be removed and the heart reperfused. The pulmonary artery anastomosis can then be completed. If the ischemic time has been short, the pulmonary artery anastomosis can be completed before removal of the cross-clamp. The recipient, having been cooled to 30°C, is rewarmed and weaned from cardiopulmonary bypass. Temporary atrial and ventricular patient wires are placed.

Technical pitfalls include redundant atrium, which can lead to stasis and thrombus formation. Bleeding from the suture lines, particularly the atrial anastomosis, has also been reported. Because of the double atrium anastomosis, mitral and tricuspid insufficiencies can occur. As a result, separate anastomosis of the supe-

Orthotopic Heart Transplant

Fig. 11.3B. Orthotopic heart transplantation. A. Four end-to-end anastomoses performed: RA, LA, aorta, pulmonary artery. B. Appearance of completed transplantation (Welch KJ, Randolph JG, Ravitch MM et al, eds. Pediatric Surgery. Chicago: Mosby-Year Book, 1986, Fig. 41-4, p. 385. Reprinted by permission.)

Fig. 11.3B. Orthotopic heart transplantation. A. Four end-to-end anastomoses performed: RA, LA, aorta, pulmonary artery. B. Appearance of completed transplantation (Welch KJ, Randolph JG, Ravitch MM et al, eds. Pediatric Surgery. Chicago: Mosby-Year Book, 1986, Fig. 41-4, p. 385. Reprinted by permission.)

rior and inferior vena cava and individual pulmonary venous implantation have been proposed.

Heterotopic heart transplantation is being considered useful as 1) a biologic-assist device; 2) in patients with elevated pulmonary vascular resistance; 3) in cases where the donor heart is too small. The technical aspects include opening of the pericardium on the right side down to the phrenic nerve to allow for the donor heart to sit in the right chest. An incision is made in the left atrium of the recipient and is then sewn to the left pulmonary veins of the donor. The donor right pulmonary veins are ligated. Caval anastomoses are completed by sewing the superior vena cava of the donor to the recipient, and the inferior vena cava is ligated. The aorta of the donor is sewn in an end-to-side fashion to the recipient, and the pulmonary artery is similarly connected in an end-to-side fashion using prosthetic graft material as needed.

Table 11.4. Cardiac drugs

Agent Effects: Compared to normal hearts

Isoproterenol Unchanged or increased inotropic and chronotropic effect

Dobutamine Unchanged inotropic and chronotropic effect

Epinephrine Unchanged inotropic and chronotropic effect Norepinephrine Unchanged inotropic and chronotropic effect;

no reflex brachycardia with increase in blood pressure

Dopamine Diminished inotropic response

Ephedrine Diminished inotropic response

Neosynephrine No reflex brachycardia

Atropine No effect on atrial ventricular conduction

Digoxin No effect acutely; may exert mild effect chronically

Amrinone Unchanged inotropic effect

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