Ryuma Iwaki

Three Dimensional Visualization of Human Cardiac Conduction Tissue in Whole Heart Specimens by High-Resolution Phase-Contrast CT Imaging Using Synchrotron Radiation:

Background: The feasibility of synchrotron radiation-based phase-contrast computed tomography (PCCT) for visualization of the atrioventricular (AV) conduction axis in human whole heart specimens was tested using four postmortem structurally normal newborn hearts obtained at autopsy. Methods: A PCCT imaging system at the beamline BL20B2 in a SPring-8 synchrotron radiation facility was used. The PCCT imaging of the conduction system was performed with “virtual” slicing of the three-dimensional reconstructed images. For histological verification, specimens were cut into planes similar to the PCCT images, then cut into 5-μm serial sections and stained with Masson’s trichrome. Results: In PCCT images of all four of the whole hearts of newborns, the AV conduction axis was distinguished as a low-density structure, which was serially traceable from the compact node to the penetrating bundle within the central fibrous body, and to the branching bundle into the left and right bundle branches. This was verified by histological serial sectioning. Conclusion: This is the first demonstration that visualization of the AV conduction axis within human whole heart specimens is feasible with PCCT.

Staged Biventricular Repair for Absent Aortic Valve in a Neonate

Congenitally absent aortic valve is an extremely rare and fatal cardiac malformation. We report the case of a neonate with absent aortic valve, an interrupted aortic arch, and a normal-sized left ventricle. At age 9 hours, emergency aortic valve closure and a Norwood procedure were performed to maintain coronary circulation. The patients postoperative course was complicated because of tracheomalacia and a severely dilated aorta that were treated with reduction aortoplasty at age 4 months. Finally, a staged Yasui procedure was performed at 26 months. To our knowledge, this is the first report of a successful biventricular repair for absent aortic valve.

Beating-Heart Surgery for Hypoplastic Left Heart Syndrome With Coronary Artery Fistulas

The presence of ventriculocoronary connections in patients with hypoplastic left heart syndrome and mitral stenosis-aortic atresia is a suggested risk factor for myocardial ischemia after surgical palliation. We describe a neonate with this anatomic variant of hypoplastic left heart syndrome who underwent a successful beating-heart Norwood operation, with continuous coronary perfusion. The ventricular condition could be visually confirmed during the procedure, and a postoperative echocardiogram showed preserved ventricular function. This technique is considered an effective option for minimizing myocardial damage in this patient subtype.

Trisomy 8 mosaicism with pyloric atresia and situs ambiguous

A 2544 g male neonate was born at 35 weeks 4 days’ gestation to a 28-year-old, gravida 3, para 2 mother via elective cesarean section. She did not take any medications during pregnancy. The mother was transferred to Hyogo Prefectural Kobe Children’s Hospital Perinatal Center due to polyhydramnios and fetal Correspondence: Sota Iwatani, MD, Department of Neonatology, Hyogo Prefectural Kobe Children’s Hospital Perinatal Center, 1-1-1 Takakuradai, Suma-Ku, Kobe, Hyogo 654-0081, Japan. Email: iwatani_kch@hp.pref.hyogo.jp Received 31 March 2014; revised 15 July 2014; accepted 2 September 2014. a b

Bilateral popliteal artery entrapment syndrome with asynchronous onset

Popliteal artery entrapment syndrome is recognized as a cause of lower leg claudication in patients younger than 50 years of age. We report a rare case of a patient with bilateral popliteal artery entrapment who presented with the same symptom 11 years after his first experience of popliteal artery entrapment syndrome. On both occasions, the surgery was performed in a similar manner and the patient was free from symptoms after the surgery. Since the diagnosis of popliteal artery entrapment syndrome is difficult, early detection of popliteal artery entrapment syndrome is important to prevent its progression.

Left Atrial Decompression Via Minithoracotomy During Extracorporeal Life Support

Extracorporeal membrane oxygenation through cervical cannulation is an established option for pediatric patients with acute cardiopulmonary failure. However, left-sided heart decompression is sometimes mandatory in patients with severe left ventricular dysfunction. This report describes a fast and less invasive technique for placing a left atrial cannula through a left anterior minithoracotomy approach. In 4 critically ill children, this minimally invasive technique provided satisfactory left-sided heart decompression, and this report describes a representative case.

Left Subclavian Artery Perfusion During the Norwood Operation for Interrupted Aortic Arch With Aortic Atresia.

The combination of aortic atresia and interrupted aortic arch is a rare condition. We describe a case of Norwood operation for this defect, in which a collateral artery from the descending aorta supplied coronary perfusion. The devised cardiopulmonary bypass technique is discussed, in which the left subclavian artery perfusion was utilized in addition to the cannulation to the descending aorta to secure the cerebral perfusion.

The left anterior extrapleural approach for innominate artery transection in a patient with tracheostomy and a neurological disorder

Although innominate artery transection for innominate artery compression of the trachea is recently used for prevention of life-threatening complications (e.g. massive bleeding and obstructive apnoea) in patients with neurological disorders, pre-existing tracheostomy poses a risk of mediastinal infection with sternotomy. We successfully performed innominate artery transection on such a patient via the left anterior extrapleural approach without sternotomy after confirming the anatomical configuration on three-dimensional multidetector row computed tomography angiography.