Ji Hyuk Yang

2009 H1N1 influenza virus infection and necrotizing pneumonia treated with extracorporeal membrane oxygenation

A 3-year-old girl with acute respiratory distress syndrome due to a H1N1 2009 influenza virus infection was complicated by necrotizing pneumonia was successfully treated with extracorporeal membrane oxygenation (ECMO). This is the first reported case in which a pediatric patient was rescued with ECMO during the H1N1 influenza epidemic in Korea in 2009.

How Long Can the Next Intervention Be Delayed after Balloon Dilatation of Homograft in the Pulmonary Position

Background and Objectives We investigated the effectiveness of balloon dilatation of homograft conduits in the pulmonary position in delaying surgical replacement. Subjects and Methods We reviewed the medical records of patients who underwent balloon dilatation of their homograft in the pulmonary position from 2001 to 2015. The pressure gradient and ratio of right ventricular pressure were measured before and after the procedure. The primary goal of this study was to evaluate the parameters associated with the interval to next surgical or catheter intervention. Results Twenty-eight balloon dilations were performed in 26 patients. The median ages of patients with homograft insertion and balloon dilatation were 20.3 months and 4.5 years, respectively. The origins of the homografts were the aorta (53.6%), pulmonary artery (32.1%), and femoral vein (14.3%). The median interval after conduit implantation was 26.7 months. The mean ratio of balloon to graft size was 0.87. The pressure gradient through the homograft and the ratio of right ventricle to aorta pressure were significantly improved after balloon dilatation (p<0.001). There were no adverse events during the procedure with the exception of one case of balloon rupture. The median interval to next intervention was 12.9 months. The median interval of freedom from re-intervention was 16.6 months. Cox proportional hazards analysis revealed that the interval of freedom from re-intervention differed only according to origin of the homograft (p=0.032), with the pulmonary artery having the longest interval of freedom from re-intervention (p=0.043). Conclusion Balloon dilatation of homografts in the pulmonary position can be safely performed, and homografts of the pulmonary artery are associated with a longer interval to re-intervention.

The effect of balloon valvuloplasty for bioprosthetic valve stenosis at pulmonary positions

BACKGROUNDnBalloon dilatation of a bioprosthetic valve in the pulmonary position could be performed to delay valve replacement. We proposed to identify the long-term effectiveness of such a procedure.nnnMETHODSnWe reviewed the medical records of 49 patients who underwent balloon valvuloplasty between January 2000 and December 2015. The primary goal was to determine the time interval until the following surgical or catheter intervention.nnnRESULTSnThe mean age at bioprosthetic valve insertion was 5.7 years old, and the mean age for ballooning was 11.7 years. The mean interval after pulmonary valve replacement was 71.6 months. The mean ratio of balloon size to valve size was 0.94. The pressure gradient through the pulmonary valve after balloon valvuloplasty was significantly improved (55.3u2009±u200918.5 mm Hg vs 33.8u2009±u200921.5 mm Hg, Pu2009<u2009.001). There were no significant changes in pulmonary regurgitation and no serious adverse events. Patients had a mean freedom from re-intervention of 30.6 months after balloon valvuloplasty. The interval of freedom from re-intervention was affected only by the pressure gradient before balloon valvuloplasty and the patient age at insertion. The mean interval to re-intervention in patients with pressure gradients less than 48.5 mm Hg before ballooning was 46.0 months, which was significantly longer than for those with a higher gradient (18.7 months).nnnCONCLUSIONnThe effectiveness of this process may depend on the pressure gradient before ballooning and the patient age at valve insertion. It is possible that earlier valvuloplasty at pressure gradient not over 48.5mm Hg may have a benefit to delaying re-operation.

Transfromation of Percutaneous Extracorporeal Life Support to Paracorporeal Ventricular Assist Device: A Case Report

Percutaneous extracorporeal life support (P-ECLS) is a useful modality for the management of refractory cardiac or pulmonary failure. However, venoarterial P-ECLS may result in a complication of left ventricular distension. In this case report, we discuss a patient with drug-induced dilated cardiomyopathy managed with venoarterial P-ECLS and a left atrial vent catheter. The venoarterial P-ECLS was modified to a paracorporeal left ventricular assist device (LVAD) by removing the femoral venous cannula. After 28 days of hospitalization, the patient was successfully weaned from the paracorporeal LVAD and discharged home from the hospital.