The New Zealand Norwood Procedure Experience: 22-Year Cumulative Review.

BACKGROUND: Babies born with a functional single ventricle heart and systemic outflow tract obstruction may require a Norwood (NW) procedure as the first of three staged procedures to obtain a Fontan circulation. This procedure and the following treatment pathway are associated with significant mortality. Risk factors for the Norwood procedure and the subsequent pathway are not necessarily the same. To identify these factors within New Zealand, the collective experience with the Norwood procedure was examined. METHODS: Charts from 133 New Zealand children undergoing Norwood procedure from 1992 to 2014 were examined. Deaths were assigned as "early" (30-day or in-hospital) or "late" (based on timeframe from the Norwood procedure). Cardiac anatomic, patient demographic and surgery related variables were examined. Important risk factors were identified using univariate and multivariate analysis. Kaplan-Meier survival curves were calculated. RESULTS: Survival following the Norwood procedure was 83%. Overall survival was 67% at six months, 65% at one year, and 63% at five years. Size of the ascending aorta appeared as an important risk factor with "early" death while New Zealand deprivation index and low birth weight appeared more important for "late" death. These factors each impacted overall survival. CONCLUSIONS: The Norwood procedure and subsequent medical treatment carries significant mortality in New Zealand. Cardiac anatomical factors affect survival of the immediate Norwood procedure whereas social factors weigh more significantly on longer term survival. Nevertheless, both anatomical and social factors carry real survival risk.

Tetralogy of Fallot repair: optimal z-score use for transannular patch insertion.

OBJECTIVES: Transannular patching is used to relieve significant pulmonary annular stenosis during tetralogy of Fallot repair. Although recent literature has focused on the deleterious effects of pulmonary regurgitation, inadequate relief of stenosis may increase postoperative mortality and the re-intervention rate. Patching criteria based on pulmonary annular z-scores are ambiguous because of the use of varied z-score data sets. This study aimed to generate data that could be used to optimize z-score use for patch insertion. METHODS: A retrospective review was made of medical records of patients who had a valve-sparing repair of tetralogy of Fallot between 1 January 2000 and 31 December 2010. In a selected group in which the residual gradient was confined to the pulmonary valve, the post-repair peak pressure gradient was determined by trans-thoracic echocardiography and was correlated with the intra-operative pulmonary valve annulus (PVA) diameter z-score. Regression analysis was used to examine this relationship. RESULTS: Data from 46 patients with valve-sparing repair were reviewed; the median age and median weight were 6.5 months and 6.6 kg, respectively; the 30-day mortality was 2.2%. Analysis of these data implies that 25% of the time, all patients with a PVA z-score of -1.3 would have a PVA gradient ≥30 mmHg. CONCLUSIONS: Criteria that recommend a transannular patch insertion only when the PVA diameter z-score is significantly smaller than -1.3 (e.g. -3) may result in a significant number of patients with an unacceptable post-repair PVA gradient.

Repair of left atrioventricular valve cleft defects with patch augmentation.

Operations for left atrioventricular valve insufficiency after repair of an atrioventricular septal defect can be challenging. Repair techniques largely depend on closure of the residual cleft in the anterior leaflet in conjunction with a posterior annuloplasty. Profound deficiencies in anterior leaflet tissue can make primary cleft closure impractical. A simplified technique, in which cleft closure is supported by triangular-shaped patch material, is presented along with results in 13 patients.

Birth weight and complexity are significant factors for the management of hypoplastic left heart syndrome.

BACKGROUND: Classic options for treatment of hypoplastic left heart syndrome include the Norwood procedure (NW) and heart transplantation (HT). Recently off-pump palliative procedures were introduced in the management of these patients. Risk factors influencing the decision between the NW with staged reconstruction or off-pump palliation and HT were assessed. METHODS: Between January 2002 and January 2006, 69 patients with hypoplastic left heart syndrome were referred for either a NW (n = 33) or HT (n = 36). Patients referred for HT underwent off-pump palliation (catheter-based, n = 20, or surgical hybrid procedures, n = 7) until a donor organ became available: including patent ductus arteriosus stenting (80.6%), atrial septostomy (41.7%), and branch pulmonary artery banding (55.6%). RESULTS: Heart transplantation patients were more complex, based on a higher Aristotle Comprehensive Complexity score calculated at birth (HT 18.8 +/- 2.4 versus NW 17.7 +/- 1.7; p < 0.05). Presurgical death was significantly greater for HT referrals (HT 27.8% versus NW 3.0%; p < 0.01); however, there was no difference between the two groups in operative (HT 11.5% versus NW 21.9%; not significant) or overall mortality (HT 36.1% versus NW 24.2%; not significant). No independent risk factors for death were identified with HT; however, a lower birth weight (<2.5 kg) and a higher Aristotle score (>20) correlated with surgical death with NW (p < 0.01). Noticeably, surgical survival was 85.7% for infants with birth weight of 2.5 kg or greater undergoing NW. CONCLUSIONS: Overall survival is similar for hypoplastic left heart syndrome patients referred for the NW or HT. Lower birth weight and higher complexity are risk factors for patients undergoing NW. Off-pump palliation followed by HT or further staged palliation should be considered for these high-risk hypoplastic left heart syndrome patients.

Biventricular repair in double outlet right ventricle: surgical results based on the STS-EACTS International Nomenclature classification.

BACKGROUND: The STS-EACTS International Nomenclature for Congenital Heart Surgery (CHS) defines four anatomic subtypes of double outlet right ventricle (DORV) based on the relationship of the ventricular septal defect (VSD) with the great vessels and the presence of right ventricular outflow tract obstruction (RVOTO). We reviewed our experience with DORV patients and two ventricles that underwent repair, applying this nomenclature. METHODS: Between January 2000 and January 2005, 50 patients with DORV and two viable ventricles underwent surgical intervention: 44 patients had biventricular repair, 3 had 1.5 ventricular repair, 2 underwent a Fontan, and 1 died prior to corrective surgery. Median age at repair was 9.1 months (range: 4D-4Y). Eighteen patients (36%) were DORV-Fallot (including 5 with AVSD and heterotaxy), 9 (18%) were DORV-TGA (Taussig-Bing), 12 (24%) were DORV-VSD, and 11 (22%) were DORV non-committed VSD. Corrective surgery included 35 repairs with a VSD-aorta baffle+/-RVOTO procedure and 12 arterial switches with a VSD-PA baffle (9 Taussig-Bing and 3 DORV-ncVSD). Associated procedures included 13 VSD enlargements, 8 subaortic resections, 9 arch repairs, 5 AVSD repairs, and 7 others. RESULTS: There were three deaths in the 50 patients studied (overall mortality of 6%). Excluding one patient that died prior to corrective surgery and the two patients palliated with a Fontan procedure, the actual surgical mortality for a corrective repair was 4.3% (2/47 patients). Two surgical deaths occurred following, respectively, one repair of a Taussig-Bing with an interrupted arch and a Swiss cheese VSD and one repair of ncVSD-type with pulmonary atresia that had undergone a previous cavo-pulmonary anastamosis. No late deaths occurred. Two late reoperations included a heart transplant in a DORV-Fallot patient with Swiss cheese VSD and subaortic resection in a DORV-ncVSD patient. Angioplasties were needed for PA stenosis (n=2) and aortic arch obstruction (n=2). Four patients had LV to aorta baffle gradients between 10 and 20 mmHg. All patients were of NYHA class I/II. CONCLUSIONS: The STS-EACTS International Nomenclature provides more uniform analysis of outcomes with respect to acceptable surgical risk and mortality. Biventricular repair can be safely achieved on selected DORV, including DORV-ncVSD and DORV with AVSD and heterotaxy lesions traditionally indicated for a single ventricle palliative approach.

Transesophageal echocardiography guided placement of a coronary sinus pacing lead.

Cardiac resynchronization therapy for the treatment of medically refractory heart failure requires coronary sinus lead placement for left ventricular pacing. Coronary sinus lead placement is technically difficult with success rates reported between 53% to 98% and implantation times ranging from 90 minutes to 5 hours. We report the use of intraoperative transesophageal echocardiography to guide coronary sinus lead placement when conventional fluoroscopy failed. Transesophageal echocardiography may improve the success rate with coronary sinus lead placement and decrease the operative time required. This should be used with caution, however, as sedation, possible intubation, and esophageal manipulation have potentially morbid consequences in patients with advanced congestive heart failure.

Direct cardiac compression devices.

Ventricular assist devices employed clinically to assist the failing heart require direct contact between the device and the patient's blood. Thromboembolic events, the need for anticoagulation, hemolysis, immune reactions and infections contribute significantly to morbidity and mortality of these devices. Compressing the weakened heart from its epicardial surface, direct cardiac compression (DCC), could provide ventricular support and avoid the interactions between blood and a foreign surface. This article reviews the physiology of epicardial compression and the current progress of mechanical compression devices.