Compression brace for secondary pectus carinatum in infants and toddlers undergoing cardiac surgery with midline sternotomy.

PURPOSES: This study aimed to retrospectively assess the response to a newly developed compression brace for improving the deformity of the secondary pectus carinatum in infants and toddlers undergoing cardiac surgery with midline sternotomy. Factors affecting the response to the brace were identified. METHODS: Fifty-one children were enrolled. Severity was expressed as the protrusion angle of the sternum obtained from chest X-ray. The patients were divided into two groups by positive or negative binary residuals of the relationship between the angle at the beginning and its percentage change after wearing the brace. Logistic regression analysis was used to identify the influencing factors. RESULTS: Thirty patients (58.8%) showed zero and positive residuals to the relationship (good responders, Group G), whereas 21 patients showed negative residuals (poor responders, Group P). Male sex, severe cardiac anomaly, complex surgical procedure, multiple sternotomy, total duration, and self-discontinuation were associated with poor response to the brace by univariate analysis. The first three factors remained with high odds ratio for poor response by multivariate analysis. No adverse events occurred with the brace. CONCLUSION: Our newly developed compression brace contributed, at least in part, to improve the deformity of the secondary pectus carinatum. Further studies are required to clarify the therapeutic efficacy of anterior chest compression for secondary pectus carinatum.

A combination of polyglycolic acid fabric and fibrin glue prevents air leakage from a lung defect.

OBJECTIVES: Air leakage after lung resection is a common morbidity that may lengthen hospital stay. Applying sealant to a lesion is an effective prophylaxis in clinical practice. This study aimed to examine the effect of a combination of a bioabsorbable polyglycolic acid (PGA) fabric and fibrin glue (FG) on air sealing by measuring the in vitro mechanical strength and degradation of the fabric, and in vivo histological changes after implantation. METHODS: A defect was created in the canine left upper lung lobe, and then filled with a fibrinogen solution and covered with a PGA sheet spray-coated with fibrinogen and thrombin. After 1 and 4 weeks, air leakage from the lesion was examined in vivo under airway pressure. Tissue samples were harvested for histological assessment. RESULTS: The mechanical strength of the PGA fabric remained at 80-90% of the baseline level for 1 week in phosphate-buffered saline, and then rapidly decreased to zero thereafter. Air leakage from the lung defect was prevented by the combination of PGA fabric and FG at 1 and 4 weeks. Histological examinations showed that PGA bundles persisted with a non-specific inflammatory response for 2 weeks and then gradually broke into sparse yarns surrounded by collagen fibres and capillaries by 8 weeks. The lung defect was filled with FG at 1 week and by granulation tissue thereafter. CONCLUSIONS: These results provide evidence for the efficacy of a combination of PGA fabric and FG for the prevention of air leakage in the critical period after lung surgery.

Safety and Efficacy of Landiolol Hydrochloride in Children with Tachyarrhythmia of Various Etiologies.

The safety and efficacy of landiolol have not been fully elucidated in pediatric patients. This study aimed to clarify the safety and efficacy of landiolol in a pediatric cohort. We retrospectively assessed the clinical features of 21 pediatric patients who were administered landiolol at our hospital. We also investigated the rates of sinus rhythm conversion and heart rate response. The median patient age was 7 months (interquartile range 1-13 months). The etiology of tachyarrhythmia was junctional ectopic tachycardia in 10 patients (47.6%), atrial tachycardia in 10 patients (47.6%), and ventricular tachycardia in 1 patient (4.8%). Of the 21 children, 18 (85.7%) had congenital heart defects, including 14 (77.8%) in whom a landiolol infusion was performed perioperatively. The landiolol infusion was effective in 18 pediatric patients (85.7%), as measured by the conversion to sinus rhythm or a reduced heart rate. Atrial tachycardia in the perioperative period was terminated in all patients. Of 7 patients with tachyarrhythmias unrelated to the perioperative period, landiolol was effective in 5. No adverse effects were reported in any patient. Landiolol infusion is effective and safe in pediatric patients with tachyarrhythmia of various etiologies, especially those with atrial tachyarrhythmia during the perioperative period.

Long-term viability and extensibility of an in situ regenerated canine aortic wall using hybrid warp-knitted fabric.

OBJECTIVES: Many surgical materials promoting tissue regeneration have been explored for use in paediatric cardiac surgery. The aim of this study is to evaluate the long-term viability and extensibility of the canine aortic wall regenerated using a novel synthetic hybrid fabric. METHODS: The sheet is a warp-knitted fabric of biodegradable (poly-l-lactic acid) and non-biodegradable (polyethylene terephthalate) yarns coated with cross-linked gelatine. This material was implanted as a patch to fill an oval-shaped defect created in the canine descending aorta. The tissue samples were explanted after 12, 24 or 36 months (N = 3, 2, 2, respectively) for histological examination and biomechanical testing. RESULTS: There was no shrinkage, rupture or aneurysmal change after 24 months. The regenerated wall showed prototypical vascular healing without material degeneration, chronic inflammation, calcification or abnormal intimal overgrowth. Bridging tissue across the patch was well-formed and had expanded over time. The biodegradable yarns had completely degraded at 24 months after implantation, as scheduled, but the regenerated aortic wall demonstrated satisfactory levels of mechanical strength and extensibility in tensile strength tests. CONCLUSIONS: The sheet achieved good long-term viability and extensibility in the regenerated aortic wall. These findings suggest that it is a promising surgical material for repairing congenital heart defects. Further developments of the sheet are required, including clinical studies.

Acquired and progressive coronary arterial fistulae in patients with single-ventricle physiology and treated with pulmonary vasodilators.

BACKGROUND: Cardiac dysfunction, arrhythmia, and hepatic fibrosis are well-known complications after right heart bypass surgery in patients with single-ventricle physiology. However, little is known about coronary arterial fistulae, and only a few reports have been published. This study aimed to elucidate the clinical characteristics of these rare coronary arterial fistulae that developed as complications in cases of single-ventricle physiology after right heart bypass surgery. METHODS: We retrospectively investigated the clinical features and courses of patients who developed acquired and progressive coronary arterial fistulae after right heart bypass surgery in our hospital. RESULTS: We identified three cases of coronary arterial fistulae out of 21 patients who underwent right heart bypass surgery. All three cases underwent cardiac catheterisation for post-operative evaluation and were administered pulmonary vasodilators of phosphodiesterase type V inhibitors, antiplatelet, anticoagulation, and diuretics. Moreover, they had common clinical features such as right-dominant single ventricle and long-term exposure to chronic hypoxia. Serial angiograms revealed acquired and progressive coronary arterial fistulae. In addition, coronary arterial fistulae contributed to their symptoms of heart failure. CONCLUSION: Patients with chronic hypoxia and dominant right ventricle, who are treated with phosphodiesterase type V inhibitors, should be followed up after right heart bypass surgery to monitor the possible development of coronary arterial fistulae. Moreover, the indication for pulmonary vasodilators in single-ventricle physiology after right heart bypass surgery should be optimised to avoid adverse effects.

Synthesis of an Ellagitannin Component, the Macaranoyl Group with a Tetra-ortho-Substituted Diaryl Ether Structure.

Herein, a practical synthesis of the macaranoyl group contained in ellagitannins, i.e., a C-O digallate structure with a tetra-ortho-substituted diaryl ether bond, is described. The methodology involved an oxa-Michael addition/elimination reaction between a brominated ortho-quinone monoketal and a phenol with a hexahydroxydiphenoyl moiety in the presence of 18-crown-6 under dark conditions, followed by reductive aromatization. The existence of rotamers originating from the constructed ether moiety is discussed as well.

Synthesis of diaryl ether components of ellagitannins using ortho-quinone with consonant mesomeric effects.

Methods for synthesizing C-O digallate structures, the basic unit of diaryl ether components of natural ellagitannins, are described. In the designed building block derived from gallic acid, consonantly overlapped mesomeric effects enhanced its electrophilicity. This building block demonstrated substantial reactivity to improve the synthesis of dehydrodigalloyl, tergalloyl, and valoneoyl groups.

A modified multi-patch technique for double-layered repair of ischemic posterior ventricular septal rupture.

BACKGROUND: The rupture of the posterior ventricular septum after acute inferior myocardial infarction is more challenging to repair than ruptures in other sites since it is less accessible and anatomically restricted. We described a modification of Daggett's original technique of multi-patch repair of ruptured posterior septum. CASE PRESENTATION: The technique was employed in the operation of a 67-year-old male who presented with severe heart failure at the 10th day after he developed inferior myocardial infarction. His ventricular septum had ruptured at the level between the posteromedial papillary muscle and the mitral annulus. A large endoventricular patch covered separately over the locally patched septal defect and the ventriculotomy defect which was going to be roofed eventually with an external patch. Both defects were then individually closed in double layers, holding a single continuous patch in common. The common use of a single patch expedited multilayered closure of the left ventricular defects and could minimize geometric remodeling of the covered area. The patches on both the endocardial and the epicardial sides avoided potentially fatal bleeding from the ventriculotomy site. The transmural mattress sutures incorporating ventriculotomy patches required minimal bites toward the posteromedial papillary muscle and mitral annulus, thereby preserving the mitral valve function. CONCLUSIONS: Thus, the technique enhances the advantage of the left ventriculotomy in the repair of posterior septal rupture and avoids ventriculotomy-related morbidity.

In situ tissue regeneration using a warp-knitted fabric in the canine aorta and inferior vena cava.

OBJECTIVES: Materials used in paediatric cardiac surgery have drawbacks of deterioration, calcification and pseudointimal proliferation resulting in haemodynamic disturbance. The aim of this study was to investigate whether these drawbacks can be overcome by in situ tissue regeneration using a newly developed synthetic hybrid fabric (SHF). METHODS: The SHF is an expandable, warp-knitted fabric composed of a combination of biodegradable [poly-l-lactic acid (PLLA)] and non-biodegradable (polyethylene terephthalate) yarns. The fabric is coated with cross-linked gelatin. Mechanical properties of the SHF were compared with those of 2 commercial products: expanded polytetrafluoroethylene sheet and glutaraldehyde-treated bovine pericardium. An oval-shaped defect created in the canine descending aorta or inferior vena cava was filled with the SHF patch. After 2 weeks and 1, 3, 6 and 12 (or 24 in the inferior vena cava) months, the patch was removed for histological examination and evaluation of the remaining PLLA. RESULTS: The SHF exhibited satisfactory tensile and suture retention strength for surgical implantation similar to or better than the 2 commercial products. Tissue regeneration was induced with multilayered smooth muscle cells and collagen fibres on both sides of the patch, along with a mature endothelial layer and tissue connections containing vasa vasorum across the patch in the aorta and inferior vena cava. Inflammatory reactions were minimal, and no calcium deposition occurred. The molecular weight of PLLA was reduced to half at 12 months after implantation. CONCLUSIONS: The SHF may solve the drawbacks of the existing products. Further studies of the expandability of the SHF patch after degradation of PLLA are warranted.

Development of a new surgical sheet containing both silk fibroin and thermoplastic polyurethane for cardiovascular surgery.

PURPOSE: The surgical sheets that are currently used for congenital cardiovascular surgery have several drawbacks, including material deterioration, calcification, and pseudo-intimal proliferation resulting in hemodynamic disturbance. The aim of this study was to evaluate a newly developed sheet made from a combination of silk fibroin (SF) and a synthetic polymer, thermoplastic polyurethane (TPU), for surgical use. METHODS: The hybrid SF/TPU sheet was a non-woven fabric with nanofibers that was made using the electrospinning method. The mechanical properties of the SF/TPU sheet were characterized. To determine its biocompatibility, part of the wall of the canine descending aorta was replaced with a SF/TPU sheet as a patch. The patches were removed after 3 months and a histological examination was performed. RESULTS: The flexibility, water permeability, and suture retention strength of the SF/TPU sheet were excellent and equivalent to those of existing sheets. The SF/TPU sheet had excellent handling properties and fit well into the vascular wall without needle hole bleeding. The histological examination revealed that the intimal tissue was restored well over the intraluminal surface of the explanted SF/TPU sheet, the absence of calcium deposition, and minimal inflammatory reaction, without signs of degradation. CONCLUSION: The SF/TPU sheet had excellent mechanical properties and tissue biocompatibility. These favorable features and possible biodegradability of the SF portion warrant a long-term follow-up study.

[Three Surgical Cases of Quadricuspid Aortic Valve].

Quadricuspid aortic valve is a rare congenital disease. We experienced 3 surgical cases of quadricuspid aortic valve. Patient 1 was a 72-year-old man who was noted to have a quadricuspid aortic valve associated with aortic regurgitation and an ascending aortic aneurysm(51 mm in diameter). He underwent replacement of the aortic valve and the ascending aorta. Patient 2 was a 71-year-old man with severe aortic stenosis, regurgitation, and coronary triple vessel disease. He underwent aortic valve replacement and coronary artery bypass grafting. Preoperative echocardiography revealed no abnormalities in the number of valve leaflets, but quadricuspid aortic valve was identified during surgery. Patient 3 was a 79-year-old man with severe aortic regurgitation, who underwent aortic valve replacement. In all patients, the 4 valve cusps were approximately of the same size. Multi-detector computed tomography is useful for evaluation of valve morphology. Indication of prophylactic ascending aorta replacement in patients with aortic dilatation requires further study.

[Concomitant Operations for Thoracic Aortic Aneurysm and Myasthenia Gravis;Report of a Case].

A 77-year-old man, who had been under medical treatment for myasthenia gravis without thymoma, was diagnosed with aortic arch aneurysm. He underwent total aortic arch replacement and total resection of the thymus through median sternotomy. His symptoms relating to myasthenia gravis dramatically disappeared after the surgery. The serum anti-acetyl chorine receptor antibody decreased from 2.7 to 0.7 nmol/l (N<0.2) with the reduction of oral predonisolone from 12.5 to 5 mg/day at 4 years after the surgery. The concomitant operations significantly improved his quality of life.