Analysis of preoperative condition and interstage mortality in Norwood and hybrid procedures for hypoplastic left heart syndrome using the Aristotle scoring system.

OBJECTIVE: The 'hybrid procedure', consisting of surgical banding of the pulmonary arteries with intraoperative stenting of the arterial duct, was developed as primary palliation in hypoplastic left heart syndrome (HLHS), avoiding the risks of cardiopulmonary bypass. In many centres, it is reserved for low birth weight, premature or unstable neonates; however, its role in such high risk cases of HLHS has yet to be defined. METHODS: The preoperative condition of all patients with HLHS who underwent either the hybrid or the Norwood procedure for HLHS between 2005-2011 was analysed retrospectively, using a modified comprehensive Aristotle score. We then compared operative, interstage and 1 year mortalities between the groups after Aristotle adjustment via Cox proportional hazards analyses. RESULTS: Of 138 patients with HLHS, 27 had hybrid and 111 Norwood procedures. The hybrid group had significantly higher Aristotle scores (mean 4.1 vs 1.8; p<0.001); however, there was no significant difference in mortality at any stage. At 1 year, the overall unadjusted survival among Norwood and hybrid patients was 58.6% and 51.9%, respectively, yielding an Aristotle adjusted hazard ratio for mortality among hybrid patients of 1.09 (95% CI 0.56 to 2.11, p=0.80). CONCLUSIONS: Applying a hybrid approach to high risk patients with HLHS produces a comparable early and interstage mortality risk to lower risk patients undergoing the Norwood procedure. Prospective studies are needed to establish whether the hybrid procedure is a viable alternative to the Norwood procedure in all HLHS patients in terms of both mortality and long term morbidity.

Use of covered stents to treat coarctation of the aorta.

Transcatheter treatments for coarctation of the aorta include balloon angioplasty and stent implantation. However, balloon angioplasty has its limitations and may be associated with complications, such as, recoarctation, dissection, and aneurysm formation, in adult patients. Bare metal stent implantation has offered an alternative during the last decade or so, but covered stents have been used with increasing frequency more recently, to the extent that covered stent implantation is the preferred treatment in correctly selected patients. Primary stent insertion, whether bare metal or covered, prevents elastic recoil of the aorta and may provide better and more predictable results than balloon angioplasty. Furthermore, stents are preferable for the treatment of complex aortic arch obstructions, but their usage is limited to older patients, because of limitations associated with growth.

Factors related to successful transcatheter closure of atrial septal defects using the Amplatzer septal occluder.

The Amplatzer septal occluder (ASO) is used for transcatheter closure of atrial septal defects (ASDs). This study aimed to determine the factors influencing successful closure with the ASO. A retrospective analysis of 69 patients who underwent transcatheter ASD occlusion between 2003 and 2007 was performed. The ASO was successfully implanted during 67 (97%) of 69 procedures. A major adverse event occurred for 6 patients (9%), and 13 patients (19%) experienced a minor adverse event. The outcome for 53 cases (77%) was a composite clinical success. Patient age (p = 0.191) and consultant experience (p = 0.270) were not important factors in successful ASD occlusion. However, patient weight (p = 0.031), diameter of the defect (p = 0.030), device size (p = 0.044), aortic rim size (p = 0.002), and device/defect ratio (p < 0.001) all were significant factors. Complications were significantly more likely for patients whose device/defect ratio was <1.125 (loose) or > or = 1.333 (tight) (p < 0.001). The device/defect ratio may provide a clinically useful tool with the potential to predict patients likely to experience an adverse event as a result of transcatheter ASD occlusion. A larger sample would enable refinement of the device/defect ratio and provide a more robust prediction of success.

Difficult to treat recurrent stenosis of the aorta.

The risk associated with repeated treatment of aortic stenosis is as high as 5% and increases to as much as 25% in complex heart diseases. Among the methods that are commonly accepted and used in the treatment of recurrent aortic stenosis are balloon dilatation and stent implantation. In this study we describe five patients with recurrent stenosis of the aorta treated with stent implantation. The short-term results of such treatment are promising. However, in some cases it is only palliative in character and does not completely resolve the problems arising from congenital heart disease. (Cardiol J 2007; 14: 186-192).

Role of stents in congenital heart disease.

For more than 10 years, balloon-expandable intravascular stents have become an integral part of treatment for obstructive vascular lesions in children and adults with congenital heart disease. The initial problems with stents, such as sharp edges, rigid frame and unacceptable shortening when over-expanded have been overcome to a large extent with the newer designs. The problems related to delivery of stents, such as stent migration, balloon rupture, flaring of the edges of the stent, rupture of vessels and milking of the stent off the balloon, have also been overcome by newer designs of balloons. The failure of growth of balloon-expandable stents with the growth of the child is managed by redilation with or without additional stenting and newer growth stents. Self-expanding stents are not appropriate for use in growing children due to the limitation of their maximum diameters. The development of biodegradable stents may overcome these disadvantages in the future. Various new developments have recently occurred. Covered stents are ideal for treating acute vessel rupture and in isolating vascular aneurysms. Drug-eluting stents may prevent restenosis, but have not been used in children. Valved stents are a recent innovation for the treatment of regurgitant pulmonary valves.