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Open in new tab Download slide OBJECTIVES To mitigate the shortage of homograft sources, the use of handmade trileaflet expanded polytetrafluoroethylene valves in pulmonary valve replacement has shown excellent results from multicentre studies conducted in Japan. However, world-wide data outside Japan are relatively insufficient. This study presents the long-term results of a single surgeon's use of flipped-back trileaflet method in a 10-year case series. METHODS We have developed an efficient way to make a trileaflet-valved conduit utilizing flipped-back method for pulmonary valve replacement and have employed the technique since 2011. Retrospective data were studied between October 2010 and January 2020. Echocardiography, electrocardiogram, Pro-Brain Natriuretic Peptide and Magnetic Resonance Imaging data were analysed. RESULTS Fifty-five patients were reviewed and median follow-up duration was 2.9 years. The majority of diagnoses was Tetralogy of Fallot (n  = 41), and these patients subsequently underwent secondary pulmonary valve replacement at a median age of 15.6 years. Survival was 92.7% with the longest follow-up period being 10 years. There was no need for reoperation, and freedom from reintervention was 98.0% at 10 years. There were 4 deaths (3 in-hospital and 1 outpatient). One patient eventually received transcatheter pulmonary valve implantation. Postoperative echocardiography showed mild or less pulmonary stenosis and pulmonary regurgitation degree in 92.2% and 92.0% of patients, respectively. Comparable magnetic resonance imaging data (n  = 25) showed significant reduction in right ventricular volumes but not in ejection fractions. CONCLUSIONS Our series showed satisfactory long-term function of handmade flipped-back trileaflet-valved conduit used in our patients. The simple design is efficiently reproducible without complex fabrication process. [ABSTRACT FROM AUTHOR]

Heterograft and artificial materials have been used for extracardiac conduit implantation to create right ventricular (RV) to pulmonary artery (PA) continuity for biventricular repair in Japan because of the limited availability of homograft valves. However, few studies have examined morphological changes and number of candidates for transcatheter pulmonary valve implantation (TPVI) in which the conduit includes more than one type of material. Overall, 88 patients who underwent biventricular repair with an external conduit were included in this evaluation. Based on catheterization data and surgical records, we estimated morphological change in the RV outflow tract for each material and the number of candidates for Melody valve implantation based on premarket approval application criteria established by the U.S. Food and Drug Administration. There were 63 candidates for TPVI (72%, 63/88). Median anteroposterior and lateral diameter of the RV outflow tract was 20.4 mm (range 9.0–41.5) and 17.8 mm (range 9.5–34.9), respectively. Bovine pericardium tended to dilate by 11.2%. Polytetrafluoroethylene (ePTFE), homograft, and Dacron polyethylene terephthalate (PET) tended to become stenotic by 11.1%, 28.0%, and 13.4%, respectively. While ePTFE (27/33, 82%) and Dacron PET (2/2, 100%) were highly suitable for TPVI, bovine pericardium (32/48, 67%) was less suitable. In Japan, many patients with hemodynamic indications for TPVI following extracardiac conduit implantation to create RV to PA continuity may also meet the morphological indications. [ABSTRACT FROM AUTHOR]

Twin to twin transfusion syndrome (TTTS) is a major complication of monochorionic diamniotic (MD) twins, and its onset is known to be associated with placental vascular anastomoses and blood flow imbalance. In a typical case of TTTS, the recipient develops polyhydramnios, weight gain, cardiomegaly and hydrops fetalis in the uterus. In contrast, the donor develops oligohydramnios and intrauterine growth restriction. Recently, the significance of the renin-angiotensin-aldosterone system (RAAS) that transfers from the donor to the recipient has attracted interest in the fetal circulation of TTTS. The donor has decreased renal blood flow due to decreased circulating blood volume. For this reason, the secretion of RAAS hormones is augmented in the fetal kidneys of the donor. In TTTS, these RAAS hormones from the donor transfer to the recipient through the anastomosed vessels. In addition to excess preload, the recipient heart is exposed to excess afterload due to systemic vasoconstriction through RAAS hormones. Commonly occurring complications in the recipient include myocardial hypertrophy, atrioventricular valve regurgitation, and pulmonary valve stenosis or pulmonary atresia. Fetoscopic laser photocoagulation (FLP) has been introduced recently because neither mortality nor neurological morbidity have been satisfactorily improved with conventional treatment. FLP is a curative method that may improve the prognosis of TTTS. In Japan, this procedure has been performed frequently, and positive neurological outcomes have been achieved. [ABSTRACT FROM AUTHOR]