Keisuke Nakanishi

A new technique for venous unifocalization of the bilateral superior vena cava with the Glenn procedure

The bidirectional Glenn procedure has been used as an intermediate stage for Fontan completion. In this staged operation, a bilateral, bidirectional Glenn procedure is performed in patients with a bilateral superior vena cava (SVC). With the bilateral SVC anatomy, the small aperture of the bilateral SVC reduces blood flow volume, and unbalanced flow can cause the stasis of blood, unbalanced pulmonary blood flow, and thrombosis formation. To resolve these issues, a new surgical technique, which we named the ‘‘unifocalization of bilateral SVC,’’ was tried as a part of the Glenn procedure. We hypothesized that single-vessel blood flow from the dual SVCs would distribute to both lungs in a manner similar to that of the unilateral Glenn procedure. In this study, we describe this new surgical procedure along with results and surgical limitations of this method.

Mechanisms of Left Ventricular Dysfunction Assessed by Layer-Specific Strain Analysis in Patients With Repaired Tetralogy of Fallot

BACKGROUND Left ventricular (LV) dysfunction in patients with repaired tetralogy of Fallot (rTOF) is an important risk factor for adverse outcomes. The aim of this study was to assess the details and time course of such LV dysfunction using layer-specific strain analysis by echocardiography.Methods and Results:The 66 patients with rTOF (mean age, 16.3±9.3 years) were divided into 3 groups (T1: 4-10 years, T2: 11-20 years, T3: 21-43 years), and 113 controls of similar age (mean age, 17.2±9.3 years) were divided into 3 corresponding groups (C1, C2, and C3). Layer-specific longitudinal strain (LS) and circumferential strain (CS) of 3 myocardial layers (endocardial, midmyocardial, and epicardial) were determined by echocardiography. Basal and papillary endocardial CS values were decreased in T1 compared with C1. With the exception of papillary epicardial CS, basal/papillary CS and LS of all 3 layers decreased in T2 compared with C2. Excepting papillary epicardial CS, all other values were decreased in T3 compared with C3. CONCLUSIONS Potential myocardial damage was found in the endocardium at the basal and papillary levels of the LV in young patients with rTOF, extending from the endocardium to the epicardium and from the base to the apex. This is the possible time course of LV dysfunction in patients with rTOF.

Ventricular septal defect closure in a patient with achondroplasia.

Achondroplasia with co-morbid CHD is rare, as are reports of surgical treatment for such patients. We present the case of a 13-year-old girl with achondroplasia and ventricular septal defect. Her ventricular septal defect was surgically repaired focussing on the cardiopulmonary bypass flow, healing of the sternum, and her frail neck cartilage. The surgery and recovery were without complications.

Usefulness of extracorporeal membrane oxygenation using double roller pumps in a low body weight newborn: A novel strategy for mechanical circulatory support in an infant.

Extracorporeal membrane oxygenation (ECMO) with a centrifugal pump requires a certain flow rate; therefore, its application for low body weight infants is frequently accompanied by oxygenator membrane malfunction and/or inadequate perfusion. To prevent low-flow associated complications, we report a case in which a novel system of dual roller pumps was used. A baby girl with a body mass index 0.25 m 2 , who experienced difficulty weaning from cardiopulmonary bypass after a Norwood-like operation, required an ECMO. Concerns for the tube lifespan reduction due to roller pump friction led to the use of a double roller pump circulation. The termination of ECMO during tube exchange is not needed, because circulation is maintained by another roller pump. The novel strategy of ECMO with double roller pumps will allow low perfusion rate to provide adequate circulatory support for low body weight patients.

Simultaneous total cavopulmonary connection and cardiac re-synchronisation therapy

We report the simultaneous use of cardiac re-synchronisation therapy and total cavopulmonary connection in a patient with dyssynchrony, wide QRS, and cardiac failure. To our knowledge, this simultaneous approach has not been reported previously. On follow-up, we noted that QRS width and brain natriuretic peptide levels improved. In addition, speckle tracking revealed improved synchronisation of ventricular wall motion.

Management of congenital complete heart block in a low-birth-weight infant.

Pacemaker implantation in infants during the early postnatal period is difficult because of their small body size and susceptibility to infection. We describe the successful pacemaker implantation for complete heart block in an infant weighing 803 g.

Novel visualised three-dimensional images are useful for treating coronary artery fistulas in infants.

Here we report an infant with coronary artery fistulas. To clearly visualise the fistulas and surrounding materials, we utilised three-dimensional computed tomography, and the images were transferred as novel visualised three-dimensional images using a reconstruction technique. With the images, we could repair the fistulas accurately. We believe that these images are useful for repairing coronary artery fistulas in infants.