William S. McMahon

Pulmonary Vein Stenosis After Catheter Ablation of Atrial Fibrillation

BACKGROUND This report describes the complication of pulmonary vein stenosis with resultant severe pulmonary hypertension that developed in 2 patients after successful catheter ablation of chronic atrial fibrillation. METHODS AND RESULTS Three months after successful catheter ablation of atrial fibrillation, both patients developed progressive dyspnea and pulmonary hypertension. Both were found to have severe stenosis of all 4 pulmonary veins near the junction with the left atrium. Balloon dilation of the stenotic pulmonary veins was performed in these patients, with improvement in dyspnea and pulmonary hypertension. CONCLUSIONS The complication of pulmonary vein stenosis is potentially life-threatening, and the application of radiofrequency current within the pulmonary veins with standard catheter technology should be avoided. This complication can be treated with balloon dilation, although the long-term course is unknown.

Etiology and retrieval of retained central venous catheter fragments within the heart and great vessels of infants and children

BACKGROUND The use of centrally positioned venous catheters plays an indispensable role in the care of infants and children. METHODS Since 1992 the authors have seen nine patients who experienced fragmentation and migration of catheter fragments into the central circulation. The patients ranged in age from 6 days to 15 years. RESULTS Sites of migration included pulmonary artery (five patients), superior vena cava (two patients), hepatic vein and innominate vein (one patient). The elapsed time from recognition of retained catheter fragments until retrieval ranged from a few hours to 6 weeks. CONCLUSION All retained fragments were successfully removed during cardiac catheterization without complications.

Transcatheter Pulmonary Valve Implantation: A Comprehensive Systematic Review and Meta‐Analyses of Observational Studies

Background Transcatheter pulmonary valve implantation is approved for the treatment of dysfunctional right ventricle to pulmonary artery conduits. However, the literature is limited because of a small patient population, and it does not reflect changing procedural practice patterns over the last decade. Methods and Results A comprehensive search of Medline and Scopus databases from inception through August 31, 2016 was conducted using predefined criteria. We included studies reporting transcatheter pulmonary valve implantation in at least 5 patients with a follow‐up duration of 6 months or more. In 19 eligible studies, 1044 patients underwent transcatheter pulmonary valve implantation with a pooled follow‐up of 2271 person‐years. Procedural success rate was 96.2% (95% confidence intervals [CI], 94.6–97.4) with a conduit rupture rate of 4.1% (95% CI, 2.5–6.8) and coronary complication rate of 1.3% (95% CI, 0.7–2.3). Incidence of reintervention was 4.4 per 100 person‐years overall (95% CI, 3.0–5.9) with a marked reduction in studies reporting ≥75% prestenting (2.9 per 100 person‐years [95% CI, 1.5–4.3] versus 6.5/100 person‐years [95% CI, 4.6–8.5]; P<0.01). Pooled endocarditis rate was 1.4 per 100 person‐years (95% CI, 0.9–2.0). Conclusions Our study provides favorable updated estimates of procedural and follow‐up outcomes after transcatheter pulmonary valve implantation. Widespread adoption of prestenting has improved longer‐term outcomes in these patients.

Balloon Angioplasty for the Treatment of Left Innominate Vein Obstruction Related Chylothorax after Congenital Heart Surgery

OBJECTIVE Chylothorax complicates the postoperative course of patients after congenital heart surgery. Innominate vein thrombosis and stenosis have been associated with postoperative chylothorax. Revascularization and angioplasty can be accomplished using transcatheter techniques. We report our experience with this procedure for the management of postoperative chylothorax. DESIGN This is a retrospective case series of patients who underwent catheter revascularization and/or angioplasty of the innominate vein following cardiac surgery at our institution from January 1, 2008 through April 9, 2014. SETTING The cardiovascular intensive care unit and cardiac catheterization laboratory at the University of Alabama at Birmingham and Benjamin Russell Hospital for Children in Birmingham, Alabama were used as settings for the study. PATIENTS Out of 112 patients with postoperative chylothorax, 7 (6.3%) underwent transcatheter dilation of the innominate vein for occlusion/stenosis. The median age of the cohort was 1 month (15 days-6 years); median weight was 3 kg (2.7-22.2). Diagnosis was made a median 8 days (2-20) and persisted for a median of 24 days (9-44). Most patients failed medical management (low fat diet, nothing by mouth, and/or octreotide). RESULTS Cardiac catheterization occurred at a median 9 days (2-29) after chylothorax diagnosis. Median chest tube output on the day prior to procedure was 63 (12-149) cc/kg/day and decreased to 23 (0-64) cc/kg/day 2 days postprocedure (P = .01). Effusions resolved in a median of 5 days (1-16). There were no clinical complications postcatheterization. All patients who have undergone repeat angiography have maintained patency of the innominate vein. There was no mortality. Complications from chylothorax included prolong hospitalization, hyponatremia, hypoproteinemia, coagulopathy, lymphopenia, and infection. CONCLUSIONS Innominate vein occlusion and stenosis associated with chylous effusion are amenable to transcatheter revascularization and/or angioplasty, consistently leading to improvement, if not full resolution of chylothorax.

Utility of Live/Real Time Three‐Dimensional Transesophageal Echocardiography in the Assessment and Percutaneous Intervention of Bioprosthetic Pulmonary Valve Stenosis

Accurate echocardiographic evaluation of the pulmonary valve is technically difficult because of its close proximity to the left lung, which often limits decision making. Pulmonary valvotomy is the intervention of choice for symptomatic pulmonary valve stenosis, but fluoroscopy lacks appropriate real time anatomic detail. In this report, we present a case where direct imaging of the pulmonary valve with live/real time three‐dimensional transesophageal echocardiography (3DTEE) aided in accurate evaluation and was then used to help guide and monitor successful valvuloplasty of a stenotic pulmonary valve bioprosthesis. We demonstrate that even in cases where two‐dimensional (2D) evaluation of the pulmonary valve is difficult, the use of live/real time 3DTEE allows for accurate evaluation of bioprosthetic pulmonary valve structure and function, and enhances the precision and monitoring of percutaneous valvuloplasty.

Patency of Internal Jugular Vein Following Repair after ECMO Stabilization Prior to Berlin Heart Implantation: Utility of Repaired Vein for Subsequent Cardiac Catheterization and Biopsy

OBJECTIVE The objective of this study was to examine the patency and utility for subsequent vascular access of the internal jugular vein following use in short-term extracorporeal membrane oxygenation. DESIGN Retrospective review. SETTING Pediatric cardiac intensive care unit, pediatric cardiac catheterization laboratory, and pediatric cardiac clinic. PATIENTS Four children, ages 7-178 months, requiring mechanical circulatory support. Interventions. Extracorporeal membrane oxygenation support, internal jugular vein repair, Berlin Heart mechanical circulatory support, heart transplantation, cardiac catheterization. OUTCOME MEASURES Following surgical repair, the internal jugular vein was studied with bedside ultrasound for assessment of patency. When appropriate, subsequent vascular access of the vessel was attempted and the success was reported. RESULTS Follow-up ultrasound examination demonstrated vessel patency in all cases. In patients requiring subsequent catheterization (3/4), successful vessel entry and catheterization were performed. CONCLUSIONS Repair of the internal jugular vein following use for short-term extracorporeal membrane oxygenation support can be accomplished with success. The vessel can be used for subsequent vascular access when necessary.

Novel technique of valve-sparing aortic root replacement in two children younger than 3 years of age.

A novel technique of valve-sparing aortic root replacement was applied to 2 children younger than 3 years of age with Marfan syndrome and large aortic root aneurysms. Using elements of both the remodeling and reimplantation techniques, circumferential rings from a 20-mm to 22-mm polyester graft provide stabilization at the subannular and sinotubular levels, and bovine pericardial patches create pseudosinuses. Follow-up at 2 years in 1 patient and 7 months in a second patient revealed satisfactory valve function with stable aortic root size.