Ross-kabbani operation in an infant with mitral valve dysplasia.

Background. Mitral valve replacement can be very difficult to obtain in infants because the valve annulus diameter can be smaller than the available prosthesis. Case Report. We describe the case of a 2-month-old female weighing 3.5 kg affected by mitral valve dysplasia leading to severe valve stenosis. Despite full medication, the clinical conditions were critical and surgery was undertaken. The mitral valve was unsuitable for repair and the orifice of mitral anulus was 12 mm, too small for a mechanical prosthesis. Therefore, a Ross-Kabbani operation was undertaken, replacing the mitral valve with the pulmonary autograft and reconstructing the right ventricular outflow tract with an etherograft. Results. The postoperative course was uneventful and the clinical conditions are good at 4-month follow-up. Conclusion. The Ross-Kabbani operation can be an interesting alternative to mitral valve replacement in infants when valve repair is not achievable and there is little space for an intra-annular mechanical prosthesis implant

Do not throw away anything from the pig.

Among the surgical sciences, paediatric cardiac surgery is one of the closest to the concept of reconstruction. Despite the common use of the verb \u2018to recycle\u2019 in the third millennium, this notion cannot always be applied to our field and a multitude of materials, patches and conduits have to be used, often leading to rejection, aneurysm formation, calcification and stenosis. Moreover, our population is very particular for the potential of growing inherent to the age of patients. For these reasons we are forced to use materials that can give the best results in short-term follow-up but that cannot remain effective in the longer term. The opportunity to use living materials, growing patches or valves, opens up exciting possibilities\u2014opens up incredible possibilities for our patients. The extracellular matrix (ECM) is the naturally-occurring bioscaffold that surrounds cells in almost all tissues and organ structures. It is an acellular biomaterial that is gradually remodelled, leaving behind organized and healthy tissue. When implanted as a patch, the ECM acts as a scaffold into which the patient's cells migrate and integrate until it is gradually replaced. ECMs originating from various organs have been tested and good results reported. Among the types available, the CorMatrix\u2122 patch (CorMatrix\uae, Alpharetta, Georgia, USA), which is derived from porcine small intestinal submucosa extracellular matrix (SIS-ECM), is one of the most promising options among those commercially available. In this issue of the Journal [1], Witt and colleagues report their experience in the use of the SIS-ECM CorMatrix patch in 37 paediatric patients. Their patient population was divided into four groups, depending on the implant location: septal defect patching, vascular patching, outflow tract patching or valve reconstruction. There were four deaths (10.8%) at a follow-up time of 411 \ub1 225 days (range 62\u2013757 days), with no death attributed to the implanted SIS-ECM, even though, in one patient with coronary ostial stenosis after supravalvular aortic patch enlargement, the suspicion of a relationship is legitimate. The best results were reported in the septal closure group. Unfortunately, a septal closure can be accomplished perfectly with many other cheaper materials and the potential of SIS-ECM is probably greatly reduced in this situation. In adult patients, where the extent of the patch is bigger, SIS-ECM is probably justified and could provide better results in terms of the possibility of restoring suitable cardiac muscle. In pulmonary or aortic enlargement plasty, the growth potential of SIS-ECM is interesting. In Witt's experience [1], vascular patching accounted for more than 50% of SIS-ECM patch applications (26 locations), with just one re-operation for pulmonary artery residual stenosis. No aneurysm formation was reported when used for aortoplasty [1]. This promising experience confirms that of others. Indeed, Padalino implanted SIS-ECM patch on the abdominal aorta in 15 rats [2]. Graft re-population was demonstrated as early as 15 days after implantation, while it was almost completely remodelled 180 days after implantation. No significant graft aneurysmatic dilation or detachment was present. The new aortic wall presented with an intima incorporating an endothelial lining, a media with smooth muscle cells and an adventitia containing vessels and fibroblasts [2]. The same encouraging results were not obtained in the clinical experience by McCready, who reported seven episodes of patch aneurysm among 76 patients who had undergone patch angioplasty of the carotid artery following endoarterectomy [3]. The patch used in this latter study was another SIS-ECM product (Surgisis\uae by Cook Surgical, Bloomington, IN, USA) that was thinner than CorMatrix. However, aneurysmal dilation of the graft patch has been described when the CorMatrix was used in carotid patch angioplasty. As regards right ventricular outflow tract (RVOT) reconstruction, Witt reported on six patients with one re-operation. In three patients, a unicusp SIS-ECM valve was created but, unfortunately, one patient died from low cardiac output and the other two showed moderate-to-severe valve incompetence. School reported four unicusp valves implanted in pulmonary outflow tract reconstruction with three of them competent at an average follow-up of 9 months: too short to be of significance [4]. Quarti reported 26 cases treated with SIS-ECM patch reconstruction, nine of which were cusp extension valvular repairs: five aortic, two tricuspid, one mitral and one pulmonary valve. At a mean follow-up of 12.5 months no patients had undergone re-operation and no more than mild incompetence was evident [5]. A large variability of results is evident among all the reported experiences. An interesting experimental study by Tottey confirms that differences exist in the composition, structure and mechanical properties of SIS-ECM prepared from tissues harvested from animals of different ages. In their conclusion, SIS-ECMs harvested from pigs aged 12 weeks are suitable for withstanding substantial mechanical loading after in vivo implantation and remodelling into load-bearing or force-generating tissues, while animals aged >52 weeks will yield scaffolds that may persist longer after in vivo implantation [6]. The interactions between the CorMatrix patch and the surrounding tissues can also be affected by the implantation techniques, the suture materials and other factors, potentially explaining the extreme variability of the results. In our experience in Bologna, the SIS-ECM CorMatrix patch was used in 19 locations on 16 patients (septal patch in 6; pulmonary artery patch enlargement in 5; valve reconstruction in 5 [3 aortic, 1 mitral and 1 tricuspid]; Senning procedure as part of double switch operation in 2 and aortic arch reconstruction in 1). All patients are alive at a mean follow-up of 15 months. One patient underwent re-operation for recurrent incompetence 24 months after repair of a dysplastic aortic valve. The explanted patch appeared pliable and without any calcification. Our impression is that the SIS-ECM CorMatrix patch is very useful in pulmonary artery enlargement and valve cusp extension by reason of its pliability and thinness, whilst it is probably not necessary for septal closure. Since clinical studies so far have limited follow-up, it is not possible to confirm the ability of the patch to regenerate normal tissue in anatomical and functional terms, although this has been demonstrated in experimental studies. However, the absence of calcific degeneration is encouraging and sufficiently important to recommend its use. If the material proves capable of allowing for growth, previously unimagined possibilities will open up, forever solving all the problems related to the use of non-living materials

Neonatal coarctation repair using extended end-to-end anastomosis

Aortic coarctation without associated intracardiac lesions, with or without posterior arch hypoplasia referred as simple coarctation, is safely and effectively repaired via left posterolateral thoracotomy, whereas median sternotomy and cardiopulmonary bypass are necessary for aortic arch reconstruction in case of complete aortic arch hypoplasia, or coarctation with associated cardiac lesions. There is a wide variety of techniques currently proposed to repair neonatal coarctation, all reported associated with very low operative mortality, nevertheless which one would be the best technique in terms of minimal rate of residual or recurrent obstruction or late complications is still under debate

Tetralogy of Fallot with coronary-to-pulmonary artery fistula: a diagnostic snare.

An 11-month-old infant, moderately cyanotic, with diagnosis of tetralogy of Fallot underwent corrective surgery. At echocardiographic evaluation, a subatretic right ventricular outflow tract without aortopulmonary collateral arteries, confluent pulmonary arteries and normal coronary pattern were evidenced. During operation, an undiagnosed large coronary-to-pulmonary artery fistula was disclosed. Because of the large variety of aortopulmonary collateral arteries that can be associated with this pathology, further imaging study is mandatory when oxygen saturation does not match the right ventricular outflow tract obstruction severity

Neonatal aortic arch surgery

Surgical repair of the aortic arch is entailed in the neonatal period of patients with: hypoplastic left heart syndrome, interrupted aortic arch, hypoplastic aortic arch and complex aortic coarctation. Aortic arch surgery requires a period of circulatory arrest and deep hypothermia. Cerebral selective perfusion has recently been introduced as an alternative to circulatory arrest with the aim of reducing mortality and neurological complications. Moreover, the arch reconstruction phase can be safely performed under moderate hypothermia and with cerebral and myocardial perfusion (on beating heart), thus, completely avoiding cerebral ischemia and completely avoiding or drastically reducing myocardial ischemi

Left main coronary artery stenosis secondary to severe pulmonary artery dilation.

A 45-year-old lady with dyspnea and occasional precordial chest pain was diagnosed with a huge sinus venosus atrial septal defect and partial anomalous pulmonary venous return. Preoperative coronary angiography disclosed severe main stem stenosis, considered secondary to compression by the dilated pulmonary trunk. Atrial septal defect closure and pulmonary artery reduction plasty were performed. The left main coronary artery appeared completely patent. The postoperative course was uneventful, and the patient was asymptomatic on follow-u

Pulmonary artery banding.

Pulmonary artery banding (PAB) is a simple surgical technique to reduce pulmonary overcirculation in some congenital heart disease. In the beginning, when the use of cardiopulmonary bypass was affected by many deleterious effects, this technique played a fundamental role in the treatment of patients with congenital heart defects and an intracardiac left-to-right shunt. The use of PAB has decreased during the last two decades, due to the increasing popularity of early complete intracardiac repair, which results have shown to be superior to staged repair, even in low body weight patients. Moreover, several authors have emphasized the negative effects of PAB such as pulmonary arterial branch distortion, abnormal right ventricular hypertrophy, pulmonary valve insufficiency, sub-aortic obstruction and decreased ventricular compliance in patients with univentricular heart. For all these reasons, this procedure has been placed in the dark corner of surgery, representing, between 2002 and 2005, ∼2% of the total amount of cardiac surgery procedures. In a more recent era, PAB has been performed in instances other than classic univentricular heart, as palliation in small infants with cardiac defects with a left-to-right shunt and pulmonary overcirculation, thus gaining some time prior to a planned staged repair. Recently, the role of PAB is becoming more important in selected subsets of congenital cardiac defects: L-transposition of the great arteries, D-transposition of the great arteries, hypoplastic left heart syndrome, moderately hypoplastic left ventricle (congenitally corrected transposition of the great arteries). This renewed interest in the banding procedure is spurring all surgeons and cardiologists to find new solutions for an easier banding procedure while making debanding less traumati