Selective Cerebro-Myocardial Perfusion in Hypoplastic Aortic Arch Repair

Objectives

Deep hypothermia and cardioplegic myocardial arrest, with or without selective cerebral perfusion, is traditionally performed during aortic arch reconstruction. In the following video, the authors describe a technique for selective cerebral perfusion combined with controlled coronary perfusion for hypoplastic aortic arch repair.

Case Summary

A week old neonate (2.8 kg) with a fetal diagnosis of a double inlet left ventricle, discordant ventriculo-arterial connection, large VSD, and a hypoplastic aortic arch was discussed at a multidisciplinary meeting for urgent surgical correction. Post-natal echocardiography confirmed the diagnosis, showing a non-restrictive VSD and a severely hypoplastic transverse arch at the level of the left subclavian artery. The planned surgical procedure was an aortic arch repair and pulmonary artery band. Through the midline sternotomy, an arterial cannula (8 French) was directly inserted into the innominate artery and a cardioplegic cannula was inserted into the aortic root. A single stage atrial cannula was used for venous return. Under mild hypothermia (30°C), the descending aorta was clamped, the isthmus and the duct ligated, and all ductal tissue removed. The aorta was then cross-clamped. Myocardial flow was maintained via the rotor of the cardioplegia line, through the delivery system, at 15-20 mL/Kg/min. Neuro clips were applied to the origin of the head and neck vessels. Cerebral blood flow rate was regulated at 50-100 ML/Kg/min, keeping the mean blood pressure in the right radial artery around 50 mm Hg. Near-infrared spectroscopy was used to monitor the efficacy of cerebral perfusion. The arch repair was achieved with a direct end-to-side anastomosis. During the procedure, the myocardium was empty and well perfused without any ECG ischemic changes. After the repair was completed and the clamps were removed, the patient was rewarmed to 36°C. A pulmonary artery band was then applied, reducing the distal pulmonary pressure to half systemic. Post-operative recovery was uneventful.

Since the introduction of this perfusion strategy at the Bristol Heart Institute, the authors have performed four additional neonatal/infant cases of aortic arch repair using selective cerebral/myocardial perfusion and mild hypothermia, with very satisfactory short-term outcomes.

Conclusion

Selective cerebral/myocardial perfusion with mild hypothermia is a safe and reproducible surgical strategy in neonates and infants undergoing aortic arch repair. It has the potential benefit of reducing the neurological and myocardial dysfunction associated with the standard deep hypothermic strategies. Nevertheless, only a prospective randomized multi-center clinical trial, or a direct comparison of propensity matched groups with long-term follow-up, can definitively evaluate the outcomes associated with this alternative perfusion strategy.

The video contained in this submission was originally presented at the 2013 AATS Annual Meeting.