Patient-specific multiscale computational fluid dynamics assessment of embolization rates in the hybrid Norwood: effects of size and placement of the reverse Blalock-Taussig shunt.

The hybrid Norwood operation is performed to treat hypoplastic left heart syndrome. Distal arch obstruction may compromise flow to the brain. In a variant of this procedure, a synthetic graft (reverse Blalock-Taussig shunt) is placed between the pulmonary trunk and innominate artery to improve upper torso blood flow. Thrombi originating in the graft may embolize to the brain. In this study, we used computational fluid dynamics and particle tracking to investigate the patterns of particle embolization as a function of the anatomic position of the reverse Blalock-Taussig shunt. The degree of distal arch obstruction and position of particle origin influence embolization probabilities to the cerebral arteries. Cerebral embolization probabilities can be reduced by as much as 20% by optimizing graft position, for a given arch geometry, degree of distal arch obstruction, and particle origin. There is a tradeoff, however, between cerebral pulmonary and coronary embolization probabilities.

Supra-aortic vessel reconstruction in total arch replacement for acute type A dissection: Comparison of en bloc and separate graft techniques.

OBJECTIVE: To compare the outcomes of the en bloc and branched graft techniques for supra-aortic vessel reconstruction in total arch replacement (TAR) for acute type A aortic dissection (ATAAD). METHODS: In 53 ATAAD patients with intact supra-aortic arch vessels undergoing TAR, the arch vessels were reconstructed using the branched graft technique in 35 patients and en bloc technique in 18, i.e. reimplantation of the innominate artery and the left carotid artery (LCA) and transposition of left subclavian artery to LCA. The early and mid-term outcomes were compared between two groups. RESULTS: The selective antegrade cerebral perfusion time in en bloc group was significantly longer (33 ± 10 vs 24 ± 7 min, p = 0.001). Operative mortality was 5.7% (3/53), including 1 and 2 in the en bloc and branched graft groups, respectively (5.6% vs 5.7%, p = 0.981). Stroke occurred in 1 patient. No spinal cord injury occurred. At mean 4.3 ± 1.6 years, clinical and CT follow-up were complete in 100% and 86% (43/50). No cerebrovascular accidents or upper extremity claudication occurred. There were 4 deaths and 1 reintervention in follow-up. Survival was 88.6% and 88.9% at 3 months, and 83.3% and 88.6% at 6 months, 3 and 5 years in the en bloc and branched graft groups, respectively (p = 0.597). The arch vessels were patent in 100% (43/43) without stenosis or aneurysm. CONCLUSIONS: The modified en bloc technique could achieve comparable early and mid-term outcomes to the branched graft technique in patients undergoing TAR for ATAAD. This approach may be an alternative technique for ATAAD patients with intact supra-aortic arch vessels.

Innominate artery interposition graft simplifies the portal venous drainage method of pancreas transplantation.

Pancreas transplantation utilizing portal venous and enteric exocrine drainage has potential benefits over the standard systemic venous and bladder exocrine drainage method. Unfortunately, technical difficulties are often experienced with the arterial anastomosis after the portal venous anastomosis is completed. We have found that the addition of an innominate artery interposition graft has greatly simplified the procedure.

Temporary aorto-pulmonary shunt for pulmonary hypertension after truncus arteriosus repair.

We describe successful management of pulmonary hypertension with a reversible aorto-pulmonary (central) shunt and inhaled nitric oxide gas after truncus arteriosus repair. A temporary central shunt may provide a lifeline in those cases refractory to pharmacologic pulmonary vasodilation as long as marginal systemic oxygenation can be maintained.

Aortic root replacement and coronary interposition using a cryopreserved allograft and its branch.

This communication describes a modified aortic root replacement technique using a cryopreserved allograft consisting of the aortic conduit and its branch. This method was applied in a patient suffering from infective pseudoaneurysm which had developed after aortic root replacement using an artificial graft with a mechanical aortic valve. A piece of the innominate artery obtained from the aortic allograft was used for interposition between the fragile left coronary artery root and the main conduit of the allograft.

Long-term results of innominate artery reimplantation for tracheal compression.

OBJECTIVE: To evaluate the safety and long-term efficacy of innominate artery reimplantation as treatment for innominate artery compression syndrome. DESIGN: Retrospective medical record review from January 1, 1992, to December 31, 2007, and telephone interview. SETTING: Children's hospital. PATIENTS: Twenty-two children with innominate artery compression of the trachea requiring surgical intervention. INTERVENTION: Innominate artery reimplantation for innominate artery compression syndrome. MAIN OUTCOME MEASURES: Respiratory symptoms, rigid bronchoscopy results, operative time, estimated blood loss, duration of hospitalization, and complications. RESULTS: Twenty-two patients were seen with innominate artery compression of the trachea causing respiratory distress. The diagnosis was made based on chest magnetic resonance images, computed tomographic angiograms, and rigid bronchoscopy results demonstrating significant (>75%) tracheal stenosis. Following innominate artery reimplantation, 19 patients (86%) had complete resolution of symptoms and discontinuation of respiratory support. Two patients had partial resolution, and 1 patient had no improvement. The time course of resolution was immediate in 13 patients, after 3 months in 1 patient, and unknown in 5 patients. The mean operative time was 73 minutes, with a mean estimated blood loss of 18 mL. The mean postoperative duration of hospitalization was 6.5 days, with a mode and median stay of 3 days. One patient required prolonged intubation (5 days), and another patient developed postpericardiotomy syndrome. Telephone interview of 10 patients at a mean of 5 years after surgery revealed continued resolution of respiratory symptoms if previously resolved and no long-term complications. CONCLUSIONS: Innominate artery reimplantation is a safe and effective treatment for innominate artery compression syndrome. Resolution of symptoms occurs quickly in most patients, with excellent long-term results.

Arch aneurysm repair with long elephant trunk: a 10-year experience in 111 patients.

BACKGROUND: We studied the long-term outcome of arch aneurysm repair with a long elephant trunk (LET) anastomosed at the base of brachiocephalic artery. METHODS: Between 1998 and 2008, 111 patients underwent arch aneurysm repair with LET. A 4-branched graft was sutured to the sinotubular junction, the distal ascending aorta transected, and a LET inserted into the aortic arch while selective cerebral perfusion was maintained. The graft distal end was anastomosed to the LET, incorporating the distal ascending aorta, and arch vessels were anastomosed to graft branches. RESULTS: Concomitantly, 33 patients (30%) underwent other cardiac procedures, including 11 aortic root replacements. Two patients died (1.8%) within 30 days and 7 died (6.3%) after 30 days. Perioperative morbidity included 2 (1.8%) with stroke, 3 (2.7%) with paraplegia, and 1 (0.9%) with paraparesis. Postoperative computed tomography scans revealed complete aneurysmal thrombosis around the LET in 88 patients (79%), who were monitored without a second-stage procedure. Among 23 patients with incomplete thrombosis, 19 underwent a second-stage procedure to complete distal fixation of the LET. Overall survival was 88%, 83%, and 75%, at 1, 3, and 5 years after aneurysm repair with the LET. No aneurysm rupture or reexpansion occurred in patients with complete thrombosis. Four patients with incomplete thrombosis died of rupture before the second-stage procedure. CONCLUSIONS: Our results demonstrated safety and good durability of the LET technique and suggest that this technique is a simple and safe procedure that is applicable to a variety of arch aneurysms.

Use of a donor aortic cross for arterial reconstruction of the pancreaticoduodenal allograft.

Combined liver-pancreas procurement generally requires back bench reconstruction of the arterial blood supply with a donor Y-iliac graft to the pancreas graft. A modified vascular reconstruction that uses donor aortic cross including the brachiocephalic trunk and the left carotid artery as a single arterial patch is presented. This is useful when iliac grafts are unavailable or are being used as an alternative technique.