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Objectives: An almost universal incidence of developing pulmonary arteriovenous fistulas after the Kawashima operation has been reported. Exclusion of the hepatic venous flow from the pulmonary circulation causes the development of these malformations. Redirection of hepatic venous flow to the pulmonary circulation mostly leads to the regression of the arteriovenous fistulas., Methods: We analyzed 11 patients with arteriovenous fistulas that developed after the Kawashima operation. The hepatic-to-azygos shunts were performed with an off-pump technique through a lateral thoracotomy in all but one. Operative and postoperative data were retrospectively collected., Results: No intraoperative complications occurred, and no patient died in the hospital. Up to 10-year follow-up showed a significant postoperative improvement of patients' oxygen saturation and New York Heart Association class. Apart from 2 re-thoracotomies for bleeding in 1 patient, no complications occurred and no patient died during follow-up. Two other patients underwent reoperation for an undiagnosed additional hepatic vein. The improvement of patients' oxygen saturation and New York Heart Association class persisted during the follow-up period., Conclusions: The surgical connection can be performed safely with an off-pump technique that avoids the risks related to extracorporeal circulation and circulatory arrest. The results at 10 years follow-up confirmed the efficacy and safety of the surgical technique described., (Copyright © 2015 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.)

Objective: Pulmonary arteriovenous malformations are an important but uncommon complication of cavopulmonary connection, particularly in patients with heterotaxy. Absence of hepatic venous effluent in pulmonary arterial blood seems to be a predisposing factor. Pulmonary arteriovenous malformations are most common after superior cavopulmonary anastomosis, but may develop, progress, or persist in 1 lung after Fontan completion if hepatic venous blood streams completely or primarily to the contralateral lung., Methods: Among 53 patients with heterotaxy and inferior vena cava interruption who underwent a modified Fontan procedure from 1985 to 2005, 8 had unilateral streaming of hepatic venous flow and clinically significant pulmonary arteriovenous malformations after hepatic venous inclusion and underwent reconfiguration of the cavopulmonary pathway. In all 8 patients, the hepatic vein-pulmonary artery pathway was contralateral to and offset from the pulmonary artery anastomosis of the single or dominant superior vena cava. Pathway reconfiguration included pulmonary arterial stenting (n = 2), revision of the superior vena cava-pulmonary artery connection (n = 1), construction of a branched hepatic vein-pulmonary artery conduit (n = 2), and surgical or transcatheter construction of a direct hepatic vein-azygous vein pathway (n = 5)., Results: Hepatic vein-azygous vein connection led to improvement in 4 of 5 patients; other approaches typically did not lead to improvement., Conclusions: Resolution of hypoxemia after cavopulmonary pathway reconfiguration in patients with unilateral pulmonary arteriovenous malformations and hepatic venous flow-streaming after Fontan completion supports the importance of hepatic venous effluent in the pathogenesis of pulmonary arteriovenous malformations and the practice of cavopulmonary pathway revision in such patients. Completion or reconfiguration of the Fontan circulation with direct hepatic vein-azygous vein connection may provide the most reliable mixing and bilateral distribution of hepatic venous blood in this population of patients., (Copyright © 2011 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.)

Objective: Pulmonary arteriovenous malformations caused by abnormal hepatic flow distribution can develop in patients with a single ventricle with an interrupted inferior vena cava. However, preoperatively determining the hepatic baffle design that optimizes hepatic flow distribution is far from trivial. The current study combines virtual surgery and numeric simulations to identify potential surgical strategies for patients with an interrupted inferior vena cava., Methods: Five patients with an interrupted inferior vena cava and severe pulmonary arteriovenous malformations were enrolled. Their in vivo anatomies were reconstructed from magnetic resonance imaging (n = 4) and computed tomography (n = 1), and alternate virtual surgery options (intracardiac/extracardiac, Y-grafts, hepato-to-azygous shunts, and azygous-to-hepatic shunts) were generated for each. Hepatic flow distribution was assessed for all options using a fully validated computational flow solver., Results: For patients with a single superior vena cava (n = 3), intracardiac/extracardiac connections proved dangerous, because even a small left or right offset led to a highly preferential hepatic flow distribution to the associated lung. The best results were obtained with either a Y-graft spanning the Kawashima to split the flow or hepato-to-azygous shunts to promote mixing. For patients with bilateral superior vena cavae (n = 2), results depended on the balance between the left and right superior inflows. When those were equal, connecting the hepatic baffle between the superior vena cavae performed well, but other options should be pursued otherwise., Conclusions: This study demonstrates how virtual surgery environments can benefit the clinical community, especially for patients with a single ventricle with an interrupted inferior vena cava. Furthermore, the sensitivity of the optimal baffle design to the superior inflows underscores the need to characterize both preoperative anatomy and flows to identify the best option., (Copyright © 2011 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.)

This study was designed to analyze the hemodynamic and cerebral repercussions arising from the surgical interruption of the superior vena cava. The experiments were carried out in 12 mongrel dogs under two different conditions: with shunt (group A, n = 6) and without the installation of a shunt (group B, n = 6). The period of occlusion was 35 minutes. The right atrium pressure, pulmonary arterial pressure, and aortic pressure are not significantly modified in the two groups. The intracranial pressure had an important correlation with the central venous pressure (r2 = 0.8572). In group B, the intracranial pressure had a sharp increase between the basal period (6.9 +/- 1.47 mm Hg) and the clamping superior vena cava (17.2 +/- 1.05 mm Hg), accentuated with the interruption of the azygous vein (32.2 +/- 0.7 mm Hg). In group A, the use of a shunt avoided this alteration during clamping of the superior vena cava (6.8 +/- 2.0 mm Hg) and the azygous vein (8.0 +/- 2.24 mm Hg). However, after removal of the clamps in group B, an elevated residual intracranial pressure was observed (21.1 +/- 3.33 mm Hg) in contrast to the central venous pressure, which returned to the basal values (4.4 +/- 0.7 mm Hg). The biomechanic findings of the volume-pressure curves (with Miller and Marmarou-Shapiro tests) and the cerebral necropsy showed brain damage in group B, without the shunt. Three animals had areas of hemorrhagic infarction. Histologic study demonstrated signs the incipient vasogenic edema. In group A, all findings were compatible with the normal. In conclusion, these results suggest the importance of shunting the blood in those cases of a nonobstructed superior vena cava because the clamping and reconstruction produce hemodynamic compromise and brain damage.

Four patients with presently uncorrectable cyanotic cardiac anomalies underwent a new operation, "total cavopulmonary shunt operation" or "total right heart bypass operation." These anomalies included single ventricle, single atrium, common atrioventricular valve with or without regurgitation, pulmonary stenosis, and most important, absent inferior vena cava with azygos or hemiazygos continuation. All patients had had previous systemic-pulmonary shunts. The new operation consisted of end-to-side anastomosis between the superior vena cava with azygos or hemiazygos continuation and the confluent pulmonary artery, division or ligation of the pulmonary artery trunk, and replacement of the common atrioventricular valve when regurgitation was present. Thus total venous return, except for hepatocardiac venous and coronary sinus flow, drains directly into the pulmonary artery, bypassing the right atrium and ventricle. Three patients survived the operation, and two of the three patients are now alive 4 years, 8 months and 2 years, 6 months after the operation. The two long-term survivors are in significantly improved condition, both clinically and hemodynamically. We believe that this new operation is promising in the treatment of the otherwise uncorrectable complex cardiac anomalies associated with azygos or hemiazygos continuation of the inferior vena cava. A longer follow-up is certainly mandatory before final conclusions can be reached.

A technique was employed successfully for correction of total anomalous pulmonary venous drainage into the upper right superior vena cava. A J-shaped right atriotomy was performed; the posterior flap was sutured to the anterior border of a previously enlarged atrial septal defect. The right superior vena cava was divided above the site of drainage of the pulmonary veins, and its proximal opening closed with a suture. The pulmonary venous return was directed to the left atrium in this way. The right atrial-right superior vena caval continuity was then reestablished by an anastomosis between the previously opened right atrial appendage and the distal end of the right superior vena cava. Finally the remaining atriotomy was closed. The azygos vein must be ligated to avoid systemic unsaturation. For correction of anomalous pulmonary venous drainage into the azygos vein with this technique, ligature of the azygos vein must be placed distally to the site of anomalous drainage. Three patients, aged 2 months, 7 years, and 16 years, respectively, with different anatomic types of the anomaly, were successfully operated on with this procedure. Findings displayed from the postoperative hemodynamic, echocardiographic, and clinical evaluation are encouraging, after a follow-up period that ranges from 4 months to 4 years. The advantages of the repair are discussed.