Permanent trans-venous pacing in an extra-cardiac Fontan circulation.

AIMS: In patients with an extra-cardiac Fontan circulation, there is no direct access to the heart. The insertion of a permanent pacemaker requires surgery to insert epicardial pacing wires. We present the implantation of a permanent endocardial pacing lead from the superior vena cava (SVC) into the atrium via direct passage from the right pulmonary artery (RPA). METHODS AND RESULTS: A permanent pacing lead was passed directly from the SVC to the RPA and then into the atrial mass. Direct passage from the RPA (attached directly to the right SVC) into the atrial mass was achieved using a trans-septal puncture needle. CONCLUSION: This novel technique is an alternative to epicardial pacing in patients with an extra-cardiac Fontan circulation, thus avoiding the need for surgical intervention. It may also be applied to gain access to the atrial mass for arrhythmia ablation therapy.

Transcatheter interventions in the early postoperative period after the Fontan procedure.

OBJECTIVE: To analyze the safety and clinical impact of interventional cardiac catheter procedures in the management of early postoperative problems after completion of an extracardiac Fontan procedure. BACKGROUND: The mortality after Fontan procedure has consistently decreased over the last decade. The role of interventional catheterization to address early postoperative problems in this setting has not been studied systematically. METHODS: Over a 9.7-year period, 289 patients underwent an extracardiac fenestrated Fontan procedure with two early deaths (0.7%) and takedown in four (1.4%). Twenty-seven patients (9.3%) underwent 32 interventional cardiac catheter procedures at a median interval of 12.2 (1-30) days. The median weight was 14.5 (13.5-25) kg. The case notes and procedure records were reviewed retrospectively. RESULTS: Fontan pathway obstructions were treated in 11 patients with stent implantation with good results and no complications. Stent fenestration of the Fontan circulation was performed in 16 patients with one episode of transient hemiparesis and one episode of pericardial effusion. Three patients underwent initial balloon dilatation of branch pulmonary arteries or fenestration with little effect and underwent stent treatment 6 (5-9) days later. One patient had device closure of a large atrial fenestration. In one patient, residual anterograde pulmonary blood flow was occluded using a device. There were no deaths and in-hospital course was improved in all. CONCLUSION: Interventional cardiac catheter procedures can be performed safely and effectively in the early postoperative period after Fontan completion to address hemodynamic problems. These techniques contribute significantly to achieve a very low mortality and address morbidity after Fontan completion.

Migraine Intervention With STARFlex Technology (MIST) trial: a prospective, multicenter, double-blind, sham-controlled trial to evaluate the effectiveness of patent foramen ovale closure with STARFlex septal repair implant to resolve refractory migraine headache.

BACKGROUND: Patent foramen ovale (PFO) is prevalent in patients with migraine with aura. Observational studies show that PFO closure resulted in migraine cessation or improvement in approximately 80% of such patients. We investigated the effects of PFO closure for migraine in a randomized, double-blind, sham-controlled trial. METHODS AND RESULTS: Patients who suffered from migraine with aura, experienced frequent migraine attacks, had previously failed > or = 2 classes of prophylactic treatments, and had moderate or large right-to-left shunts consistent with the presence of a PFO were randomized to transcatheter PFO closure with the STARFlex implant or to a sham procedure. Patients were followed up for 6 months. The primary efficacy end point was cessation of migraine headache 91 to 180 days after the procedure. In total, 163 of 432 patients (38%) had right-to-left shunts consistent with a moderate or large PFO. One hundred forty-seven patients were randomized. No significant difference was observed in the primary end point of migraine headache cessation between implant and sham groups (3 of 74 versus 3 of 73, respectively; P=0.51). Secondary end points also were not achieved. On exploratory analysis, excluding 2 outliers, the implant group demonstrated a greater reduction in total migraine headache days (P=0.027). As expected, the implant arm experienced more procedural serious adverse events. All events were transient. CONCLUSIONS: This trial confirmed the high prevalence of right-to-left shunts in patients with migraine with aura. Although no significant effect was found for primary or secondary end points, the exploratory analysis supports further investigation. The robust design of this study has served as the model for larger trials that are currently underway in the United States and Europe.

Transvenous pacing via a disconnected superior vena cava in a patient with transposition of the great arteries.

We describe successful implantation of a permanent pacemaker via the right subclavian vein in a 28-year-old man with operated transposition of the great arteries where the superior vena cava is completely disconnected from the systemic venous atrium following a previous Glenn procedure.

BioSTAR Evaluation STudy (BEST): a prospective, multicenter, phase I clinical trial to evaluate the feasibility, efficacy, and safety of the BioSTAR bioabsorbable septal repair implant for the closure of atrial-level shunts.

BACKGROUND: The use of permanent synthetic implants to close atrial septal defects (ASD) and patent foramen ovale (PFO) has a number of limitations, including late complications and the limiting of transeptal access to the left heart should it be required for the later treatment of acquired heart disease. BioSTAR is a novel, bioabsorbable, atrial septal repair implant. This phase I pilot study evaluates the feasibility, safety, and effectiveness of BioSTAR for the first time in humans. METHODS AND RESULTS: We conducted a prospective, open-label, multicenter clinical study in 58 patients aged 28 to 68 years who had a clinically significant ASD or PFO. Percutaneous shunt closure was undertaken with the BioSTAR septal repair implant. Successful device implantation was achieved in 57 (98%) of 58 patients. Closure at 30 days and 6 months, assessed by contrast transthoracic echocardiography, was 48 (92%) of 52 and 54 (96%) of 56, respectively. There was no evidence of a clinically significant response to the device. Transient atrial arrhythmia occurred in 5 patients after implantation. No major safety issues were observed. CONCLUSIONS: This study demonstrates the feasibility, safety, and effectiveness of BioSTAR for the closure of ASD and PFO in humans with a high rate of early and complete shunt closure. BioSTAR is a novel septal repair implant designed to provide biological closure of atrial-level defects using the patient's natural healing response. Because 90% to 95% of the implant is absorbed and replaced with healthy native tissue, future access to the left atrium may be achieved.

Factors influencing early and late outcome following the Fontan procedure in the current era. The 'Two Commandments'?

OBJECTIVE: This study was undertaken to identify the factors affecting early and late outcome following the Fontan procedure in the current era. We have examined whether conventional selection criteria, the 'Ten Commandments', are still applicable in the current era. MATERIALS AND METHODS: Between January 1988 and July 2004, 406 patients underwent a modified Fontan procedure at a median age of 4.7 years (IQR, 3.8-7.1 years). The single functional ventricle was of left (n=241, 59%) or right ventricular morphology (n=163, 40%). The modified Fontan procedure was performed using an atriopulmonary connection (n=162, 40%) or total cavopulmonary connection (TCPC) involving a lateral atrial tunnel (n=50, 12%) or extracardiac conduit (n=194, 48%). They were fenestrated in 216 patients (53%). RESULTS: The early mortality was 4.4% (n=18) and four other patients required takedown of the Fontan circulation. On multivariable analysis, early outcome was adversely influenced by two factors (p<0.05): preoperative impaired ventricular function and elevated pulmonary artery pressures. Two risk models were constructed for early outcome based on preoperative and predictable operative variables (Model 1) and all preoperative and operative data (Model 2). Both models were calibrated across all deciles (p=0.83, p=0.25) and discriminated well. The area under the ROC curve was 0.85 and 0.89, respectively. There were 21 late deaths, 1 patient required late takedown of the Fontan circulation and 3 required orthotopic cardiac transplantation. Actuarial survival was 90+/-2%, 86+/-2% and 82+/-3% at 5, 10 and 15 years, respectively. Multivariable analysis identified that outcome was influenced by preoperatively impaired ventricular function, elevated preoperative pulmonary artery pressures and an earlier year of operation. The freedom from reintervention was 83+/-4%, 76+/-4% and 74+/-8% at 5, 10 and 15 years, respectively. Additional risk factors for reintervention were right atrial isomerism and preoperative small pulmonary artery size. CONCLUSIONS: Late outcome of the Fontan circulation is encouraging. Ventricular morphology, surgical technique and fenestration do not appear to influence early or late outcome. Preoperatively impaired ventricular function and elevated pulmonary artery pressures have an adverse influence on both early and late outcome. Reintervention is common, with small preoperative pulmonary artery size being an additional risk factor.

Intention-to-treat analysis of pulmonary artery banding in conditions with a morphological right ventricle in the systemic circulation with a view to anatomic biventricular repair.

BACKGROUND: Some patients with a morphological right ventricle (mRV) in the systemic circulation require early intervention because of progressive systemic ventricular dysfunction or atrioventricular valve regurgitation. They may be eligible for anatomic repair (correction of atrioventricular and ventriculoarterial discordance) but require prior training of the morphological left ventricle (mLV). METHODS AND RESULTS: Forty-one patients with congenitally corrected transposition of the great arteries or a previous atrial switch procedure embarked on a protocol of pulmonary artery (PA) banding with a view to anatomic repair. All had an mRV in the systemic circulation and a subpulmonary mLV that was not conditioned by either volume or pressure load. Two patients were not banded, and 39 were followed up for a median of 4.3 years (range, 25 days to 12.6 years). Sixteen patients achieved anatomic repair, with 3 in the early stages of the training protocol. After 2 years, 12 patients were not suitable for anatomic repair and persisted with palliative banding; 8 were functionally improved; and 4 died, underwent transplantation, or required debanding. PA banding improved functional class but did not improve tricuspid regurgitation in the long term for patients not achieving anatomic repair. mLV function was a critical determinant of survival with a PA band as well as survival after anatomic repair. Patients >16 years were unlikely to achieve anatomic repair. CONCLUSIONS: PA banding is a safe and effective method of training the mLV before anatomic repair. It is also an effective palliative procedure for those who do not attain this goal.

Right ventricular outflow tract reconstruction using Contegra valved conduit: natural history and conduit performance under pressure.

OBJECTIVE: To assess the performance of the bovine Contegra valved conduit used for right ventricular (RV) outflow tract reconstruction, particularly in relation to post-operative RV pressure. METHODS: Follow-up study of 64 consecutive right ventricular to pulmonary artery-conduit implants in 62 patients between January 2000 and April 2003. The majority of cases were forms of pulmonary atresia/VSD (n=24, 39%) or Fallot's tetralogy (n=13, 21%). Thirteen cases (21%) had aortic atresia, truncus arteriosus or discordant connections with pulmonary atresia/VSD. Twelve cases (19%) were conduit replacements. Echocardiography was performed for a median follow-up of 14 months (range 0-38 months). RESULTS: Median age at implantation was 13.8 months (range 0.1-244 months) and median weight was 8.9 kg (range 2.1-84.1 kg). Thirty-eight patients (59.4%) were <10 kg at the time of surgery. Early mortality was 6.4% (n=4). During follow-up there were four explantations (one for endocarditis and three for conduit dilatation) and 16 (28.6%) catheter interventions. Overall freedom from intervention at 1 and 3 years was 71+/-6% and 53+/-11%, respectively. Freedom from conduit-specific reintervention was 66+/-11% at the end of the study period. Reintervention was associated with small conduits (p=0.04), age <1 year (p=0.04) and with high RV/LV pressure ratio in the immediate post-operative period (p=0.0003). On multivariate analysis, the RV/LV pressure ratio was the strongest single factor predicting the overall reintervention (OR 5.45). Acquired distal conduit stenosis at suture line was the commonest indication for conduit-specific reintervention and was associated with the smaller conduits. The conduits explanted for dilatation showed neointimal proliferation, thrombosis, calcification and chronic inflammation. CONCLUSIONS: The Contegra conduit is widely applicable to RVOT reconstruction with satisfactory mid-term results. However, there is a significant incidence of conduit-related complications, particularly with the smaller conduits. Adverse performance was strongly associated with high RV/LV pressure ratio at completion of surgery. We would recommend cautious use of the conduits in patients with predicted high RV/LV pressure ratios, where careful monitoring of conduit performance is crucial. There is some element of unpredictability, which adds to the importance of close follow-up. Further studies are needed to explore the issues of thrombogenicity, degeneration, possible 'rejection', and the potential role of anti-platelet and anti-inflammatory modulation.

Fate of pulmonary arteries following Norwood Procedure.

OBJECTIVE: This study evaluated the requirement for surgical reoperation and catheter-based reintervention to central pulmonary arteries (CPAs) following Norwood Procedure (NP). We sought to identify the influence of various surgical techniques employed during NP on subsequent interventions. METHODS: Between 1993 and 2004, 226 patients underwent Stage II following NP. Ninety-eight patients (43%) had completion of Fontan circulation (Stage III) and a further 107 (47%) are on course for Fontan completion with 21 (9%) inter-stage deaths. During NP, the aortic arch was reconstructed without additional material (n = 91, 40%) or with a pulmonary homograft patch (n = 135, 60%). Pulmonary blood flow was supplied by modified Blalock-Taussig shunt (n = 177, 78%) or right ventricle to pulmonary artery conduit (RV-PA; n = 49, 22%). The CPAs defect was closed directly (n = 69, 31%) or with a patch (n = 157, 69%). Complete resection of coarctation was performed in 126 patients (56%). RESULTS: Ninety-seven patients (43%) required surgical reoperation to CPAs during Stage II. Actuarial freedom from reoperation was 60+/-3%, 52+/-4% and 50+/-4% at 1, 5 and 10 years, respectively. On multivariable analysis, NP with RV-PA increased risk of reoperation (LR 8.3, 5.3-13.2; p < 0.001). Forty-one patients (18%) required catheter-based reintervention on CPAs. Actuarial freedom from reintervention was 98+/-1%, 72+/-4% and 58+/-6% at 1, 5 and 10 years, respectively. CPA problems were almost exclusively limited to the proximal Left pulmonary artery. On multivariable analysis, catheter-based reintervention became more common with time. Complete resection of coarctation increased risk of reintervention (LR 3.9, 1.6-9.6; p < 0.005). Arch reconstruction and CPAs repair techniques did not affect risk of reoperation or reintervention on CPAs. CONCLUSIONS: CPA stenoses and hypoplasia need surgical attention in approximately half of all patients undergoing the NP. The need for reoperation is increased when using the RV-PA conduit technique (although the majority of these are performed as part of the Stage II procedure). Catheter reinterventions are almost exclusively confined to the left CPA and are increased when the arch is shortened by resection of the coarctation tissue at time of NP.

The RV-PA conduit stimulates better growth of the pulmonary arteries in hypoplastic left heart syndrome.

OBJECTIVE: This retrospective study compared the size of the central pulmonary arteries in patients with hypoplastic left heart syndrome (HLHS) following either a classical Norwood or Norwood procedure with a right ventricle to pulmonary artery (RV-PA) conduit. METHODS: Between May 2001 and May 2003, 30 patients with HLHS underwent cardiac catheterization prior to stage II palliation. Patients were initially palliated with a classical Norwood (Classical group, n=18) or Norwood procedure with RV-PA conduit (RV-PA group; n=12). Indexed maximum and minimum diameters of the LPA and RPA were measured using the McGoon ratio. Cardiac catheterisation was performed at a median age of 4.0 months. There was no difference in the time interval to catheterisation (P=0.13), Qp:Qs (P=0.41) or median haemoglobin (P=0.42) between the groups. RESULTS: The combined PA diameter was larger in the RV-PA group (B) than the classical group (A) (1.99+/-0.38 versus 1.63+/-0.29, P<0.05). There were marked differences in the relative size of the pulmonary arteries between the two groups. In RV-PA patients, the LPA and RPA sizes were comparable (0.99+/-0.22 versus 1.00+/-0.31, P=1.00) whereas, in the classical group, the LPA was smaller than the RPA (0.75+/-0.15 versus 0.88+/-0.17, P<0.05). Both techniques were also associated with discrete PA stenoses at the site of shunt insertion. Stenoses were more severe in RV-PA group (RV-PA), causing a 42+/-16% reduction in the combined PA diameter compared with a 28+/-18% reduction in Classical group (classical) (P<0.05). CONCLUSIONS: The Norwood procedure with RV-PA conduit is associated with better and more evenly distributed central pulmonary artery growth. Nevertheless, it is also associated with central PA stenoses, which may require subsequent reconstruction.

The influence of pulmonary artery morphology on the results of operations for major aortopulmonary collateral arteries and complex congenital heart defects.

OBJECTIVE: Congenital heart defects with major aortopulmonary collateral arteries show marked variability in the size and distribution of native pulmonary arteries. We sought to classify the size and distribution of native pulmonary arteries and to determine their influence on surgical outcome. METHODS: Between 1989 and 2002, 164 patients underwent surgical intervention for congenital heart defects with major aortopulmonary collateral arteries (median age, 10 months). Three patterns of native pulmonary arteries were identified: intrapericardial native pulmonary arteries present (group I); confluent intrapulmonary native pulmonary arteries without intrapericardial native pulmonary arteries (group II); and nonconfluent intrapulmonary native pulmonary arteries (group III). Thirty-seven (23%) patients had single-stage and 76 (47%) patients had multistage complete repair. Thirty (18%) patients await septation, and 8 (5.0%) patients are not septatable. Follow-up is 98% complete (median follow-up, 5.8 years). RESULTS: In the 164 patients there were 15 (9.1%) early and 12 (7.3%) late deaths. Early mortality after complete repair was 4.4% (n = 5). Actuarial survival was 90% +/- 3% and 85% +/- 4% at 1 and 10 years, respectively. Actuarial freedom from surgical or catheter reintervention in septated patients was 77% +/- 4% and 45% +/- 8% at 1 and 10 years, respectively. On multivariate analysis, the morphology of the native pulmonary arteries was the only factor that influenced actuarial survival after complete repair (P =.04). Group III had the highest risk of death after septation (P =.008). Group II fared better than group III after the initial operation (P <.05). CONCLUSIONS: Current classifications of congenital heart defects with major aortopulmonary collateral arteries are based on the presence or absence of intrapericardial pulmonary arteries. We have identified a subgroup without intrapericardial native pulmonary arteries but with confluent intrapulmonary native pulmonary arteries. This group has a better outcome than those with nonconfluent intrapulmonary native pulmonary arteries.

Midterm results after restoration of the morphologically left ventricle to the systemic circulation in patients with congenitally corrected transposition of the great arteries.

OBJECTIVE: This study was undertaken to determine the outcomes of patients with congenitally corrected transposition of the great arteries after restoration of the morphologically left ventricle to the systemic circulation. METHODS: Between November 1991 and June 2001, a total of 54 patients (median age 3.2 years, range 7 weeks-40 years) with either congenitally corrected transposition of the great arteries (n = 51) or atrioventricular discordance with double-outlet right ventricle (n = 3) underwent anatomic repair. This comprised a Senning procedure in all cases plus arterial switch (double-switch group) in 29 cases (53.7%), plus a Rastelli procedure (Rastelli-Senning group) in 22 cases (40.7%), and plus intraventricular rerouting (Senning-tunnel group) in 3 cases (5.6%). Left ventricular training by PA banding was performed before the double-switch operation in 9 of 29 cases (31%). Follow-up is complete (median 4.4 years). RESULTS: Early mortality was 5.6% (n = 3), with 2 late deaths. Kaplan-Meier survivals (+/- SEM) were 94.4% +/- 3.1% at 1 year and 89.7% +/- 4.4% at 9 years. Survivals at 7 years were 84.9% +/- 7.1% in the double-switch group and 95.5% +/- 4.4% in the Rastelli-Senning group (P =.32). Of the 49 survivors, 46 (94%) were in New York Heart Association functional class I. Six have acquired new left ventricular dilatation or impaired systolic ventricular function. Four patients in the double-switch group had moderate aortic valve regurgitation develop, and 2 of them required valve replacement. Overall freedoms from reoperation at 1 and 9 years were 94.2% +/- 3.3% and 77.5% +/- 9.0%, with no significant difference between the groups (P =.60). CONCLUSIONS: Anatomic repair of congenitally corrected transposition of the great arteries can be carried out with low early mortality. Excellent functional status can be achieved, with good midterm survival. Continued surveillance is necessary for patents with valved conduits and to determine the longer-term function of the aortic valve and the morphologically left ventricle in the systemic circulation.

Surgical aortic valvotomy in infancy: impact of leaflet morphology on long-term outcomes.

BACKGROUND: Surgical valvotomy for critical aortic stenosis in children enables relatively accurate commissurotomies to be fashioned, resulting in the formation of two or three leaflets. We hypothesized that outcomes after surgery may be best in patients in whom three leaflets are produced. METHODS: A retrospective review of infants undergoing primary surgical valvotomy at our institution during a 12-year period was carried out. Patients who had additional intracardiac defects were excluded. Clinical and echocardiographic follow-up data were analyzed. RESULTS: Fifty-four patients fulfilled the study criteria. Median age at surgery was 3 weeks (range, 0 to 51 weeks). Commissurotomy resulted in bileaflet anatomy in 41 patients (group A) and trileaflet anatomy in 13 patients (group B). Operative mortality was 5% in group A and 0% in group B (p = 1.0). In group A, 18 patients required one or more aortic valve reinterventions, including valve replacement in 8 patients. In group B, there was only one reintervention (repeat valvotomy). Kaplan-Meier analysis showed that at 10 years, comparisons of group A versus group B were as follows: actuarial survival, 85% versus 100% (p = 0.15); freedom from reintervention, 33% versus 92% (p = 0.01); freedom from aortic reoperation, 45% versus 92% (p = 0.04); and freedom from aortic valve replacement, 57% versus 100% (p = 0.07). CONCLUSIONS: Long-term outcomes after aortic valvotomy are significantly better in infants in whom surgery results in trileaflet rather than bileaflet anatomy. Preoperative evaluation of valve morphology may enable selection of a group of patients in whom results of surgery are excellent.

The impact of ventricular morphology on midterm outcome following completion total cavopulmonary connection.

OBJECTIVE: This study was undertaken to compare the early and midterm outcome following completion total cavopulmonary connection (TCPC) in patients with a single functional ventricle of left or right morphology. METHODS: Between August 1996 and July 2001, 103 patients underwent completion TCPC following an interim superior cavopulmonary connection. The single functional ventricle was of left (n=44, 42%) or right ventricular morphology (n=59, 58%). The TCPC was performed using an extracardiac conduit (n=84, 82%) or a lateral atrial tunnel (n=19, 18%), and was fenestrated in 53 patients (51%). Outcomes studied included duration of pleural effusions and in-patient hospitalisation; early mortality, reoperation and reintervention; actuarial survival, freedom from reoperation and reintervention; and current functional status. These were assessed according to a series of preoperative, operative and postoperative variables. Follow-up was complete with a median interval of 17 months (range, 21 days-5.2 years). RESULTS: Early mortality was 1.9% (n=2) and one other patient required takedown of the Fontan circulation. There was one late death. Five-year survival with a Fontan circulation (+/-1 SEM) was 95.6+/-2.5%. Forty-two patients (41%) had prolonged pleural drainage (> or =14 days) and 41 patients (40%) had a prolonged hospital stay. Five-year freedom from reoperation and reintervention (+/-1 SEM) were 92.2+/-5.0 and 73.4+/-6.0%, respectively. The Fontan procedure was associated with an improved functional class (P<0.005) and all current survivors (n=99) are in either New York Heart Association classes I or II. Multivariate analysis identified left atrial isomerism as the single risk factor for death (P<0.05). Independent risk factors for prolonged hospital stay included a morphologic right ventricle (P<0.05), increased postoperative pulmonary artery pressures (P<0.005) and an unfenestrated Fontan procedure (P<0.01). CONCLUSIONS: In this contemporary series, the modified Fontan procedure was characterised by low early mortality, excellent midterm survival, and improved functional class independent of the morphology of the single functional ventricle. Nevertheless, a morphologic right ventricle was a risk factor for prolonged in-patient hospitalisation and may yet influence long term survival.

Surgery following primary right ventricular outflow tract stenting for Fallot's tetralogy and variants: rehabilitation of small pulmonary arteries.

OBJECTIVES: Primary surgical repair of Tetralogy of Fallot (ToF) in small infants with small pulmonary arteries (PAs) or complex anatomies can be hazardous. We assessed the effect of right ventricular outflow tract (RVOT) stenting on subsequent surgical intervention with attention to growth of the PAs. METHODS: Primary RVOT stenting was performed in 32 symptomatic patients with ToF physiology. Twenty patients had surgical intervention, with 15 undergoing complete repair to date. Median age at stenting was 61 (range 8-406) days, and median weight, 3.9 (range 1.8-12.2) kg. RESULTS: Stenting improved saturations from 72 ± 8 to 92 ± 2% (P < 0.001). Four patients required early surgical palliation for persistent desaturation (within 4 weeks). Twenty patients went on to have surgical intervention at a median time of 220 days after stenting. There was no operative mortality after complete repair. Removing the stent lengthened the procedure time and 86% required transannular patch (TAP; bypass time 109 ± 42 min, cross clamp 68 ± 29 min). Median intensive therapy unit stay was 2 days. There was 1 late death at 3 months due to chronic lung disease. The median left PA Z-score increased from a preinterventional value of -1.27 (-0.19 to -2.87) to a presurgical value of +0.11 (-4.12 to +1.97). The median right PA Z-score increased from -2.02 (-1.77 to -4.68) to -0.65 (-0.29 to -2.04) over the preinterventional and presurgical time intervals. Growth was greatest in the right PA. CONCLUSIONS: Primary RVOT stenting facilitates staged palliation for ToF in small infants and complex anatomies. Improved PA blood flow generated by the stent leads to growth of the branch PAs and may improve the substrate for subsequent surgical repair. Surgery is safe; however, the majority will require a TAP.

Stenting of the right ventricular outflow tract.

OBJECTIVE: To assess the indication, technical aspects, and outcome of stenting of the right ventricular outflow tract (RVOT) in the management of symptomatic patients with severely limited pulmonary blood flow. METHODS: Retrospective case note and procedure review of patients undergoing stenting of the RVOT over an 8 year period. PATIENTS: Between 2005 and 2012, 52 selected patients underwent percutaneous stent implantation into a very narrow RVOT to improve pulmonary blood flow. Median age at stent implantation was 63 (range 4-406) days and median weight was 3.8 (1.7-12.2) kg. RESULTS: 52 patients underwent stent implantation. Median procedure time was 57 (24-260) min and fluoroscopy time 16 (5.5-73) min. There was one procedural death (1.9%) and one emergency surgery (1.9%). Saturations increased from 71% (52-83%) to 92% (81-100%) (p<0.001). Two patients required early shunts due to inadequate palliation and two died from non-cardiac causes. Sixteen further catheter interventions were undertaken (balloon in 7, further stent in 9). Twenty-nine patients underwent delayed surgery (complete repair in 26, palliative in 3) at a median of 172 (52-758) days post-stenting. Left pulmonary artery Z score increased from a pre-interventional value of -1.75 (-4.96 to 0.67) to a pre-surgical value of -0.55 (-4.12 to 1.97), (p<0.01). Median right pulmonary artery Z score increased from -2.63 (-7.70 to 0.89) to -0.75 (-6.69 to 1.18) (p<0.01) . Seventeen patients remain well palliated after a median of 122 (40-286) days. CONCLUSIONS: Stenting of the RVOT is an effective treatment option in the initial management of selected patients with very reduced pulmonary blood flow.

Percutaneous radiofrequency septal reduction for hypertrophic obstructive cardiomyopathy in children.

OBJECTIVES: The aim of this study was to assess the efficacy of radiofrequency catheter ablation (RFCA) in the treatment of hypertrophic obstructive cardiomyopathy in children. BACKGROUND: Hypertrophic obstructive cardiomyopathy is an uncommon cause of left ventricular outflow tract obstruction in children. In symptomatic patients, open heart surgical myectomy has hitherto been the only therapeutic option. METHODS: In 32 children, at a median age of 11.1 (range 2.9 to 17.5) years and weight of 31 (15 to 68) kg, ablation of the hypertrophied septum was performed using a cool-tip ablation catheter via a femoral arterial approach. The median number of lesions was 27 (10 to 63) and fluoroscopic time was 24 (12 to 60) min. RESULTS: The majority of patients demonstrated an immediate decrease in the catheter pullback gradient (mean 78.5 ± 26.2 mm Hg pre-RFCA versus mean 36.1 ± 16.5 mm Hg post-RFCA, p < 0.01) and a further reduction in the Doppler echocardiographic gradient (mean 96.9 ± 27.0 mm Hg pre-RFCA versus 32.7 ± 27.1 mm Hg post-RFCA, p < 0.01) at follow-up. One patient died due to a paradoxical increase in left ventricular outflow tract obstruction, and another had persistent atrioventricular block that required permanent pacing. Six patients required further procedures (surgery, pacing, or further RFCA) during a median follow-up of 48 (3 to 144) months. CONCLUSIONS: The preliminary results of RFCA for septal reduction in children with hypertrophic cardiomyopathy are promising and merit further evaluation.

Treatment of dynamic subvalvar muscular obstruction in the native right ventricular outflow tract by percutaneous stenting in adults.

Percutaneous techniques are being increasingly used in adult congenital heart disease but there is limited experience in the treatment of native nonvalvar right ventricular outflow tract obstruction. We describe two cases of percutaneous stenting of the subpulmonary region where surgery was not an option.

Surgical management of hypoplastic left heart syndrome at the Birmingham Children's Hospital.

Currently, a three-stage surgical palliation remains the treatment of choice at Birmingham Children's Hospital. After initial introduction of the classical Norwood with pulmonary blood flow provided by a modified Blalock-Taussig shunt, a right ventricular to right pulmonary artery conduit at stage 1 Norwood palliation is now used in most cases, a bi-directional 'Glenn' shunt at second stage and an extra-cardiac Fontan completion at third stage. Mortality and morbidity has improved after modification of the technique. Thirty-day mortality was 32.4% (79/244) for the 'classical' Norwood procedure, 25.0% (7/28) for the left-sided RV-PA conduit and 12.7% (22/173) for the right-sided RV-PA conduit. Interstage mortality was 8.6% (21/244) for the 'classical' Norwood procedure, 14.3% (4/28) for the left and 10.1% (15/148) for right-sided RV-PA conduit. After stage II, 30-day mortality was 3.0% (10/335) for all groups. Stage III 30-day mortality was 0.9% (1/115) for all groups.

The morphologic left ventricle that requires training by means of pulmonary artery banding before the double-switch procedure for congenitally corrected transposition of the great arteries is at risk of late dysfunction.

OBJECTIVE: The aim of this study was to compare the outcome of the double-switch procedure for congenitally corrected transposition of the great arteries for patients completing morphologic left ventricle training by means of pulmonary artery banding with the outcome of patients whose morphologic left ventricle did not require training. METHODS: A retrospective study of all patients undergoing the double-switch procedure from 1991 through 2004 was performed. Patients were divided into 2 groups: those not requiring morphologic left ventricle training (n = 33) and those completing morphologic left ventricle training by means of pulmonary artery banding (n = 11). RESULTS: The time spent with the morphologic left ventricle conditioned at systemic pressures was longer for the group not requiring morphologic left ventricle training (median, 730 days; interquartile range, 399-1234 vs median, 436 days; interquartile range, 411-646; P = .19). The overall mortality (not requiring morphologic left ventricle training, 12.1%; requiring morphologic left ventricle training, 9.1%; P = 1) and rate of death/transplantation, development of moderate-to-severe morphologic left ventricle dysfunction, or both (not requiring morphologic left ventricle training, 21.2%; requiring morphologic left ventricle training, 45.5%; P = .14) were similar between groups. Actuarial freedom from death/transplantation with good morphologic left ventricular function was superior for patients whose morphologic left ventricle did not require training (P = .04). The follow-up was not different between groups (not requiring training: median, 1435 days [interquartile range, 285-2570 days]; requiring morphologic left ventricle training: median, 568 days [interquartile range, 399-1465 days]; P = .14). On multivariate analysis, the completion of morphologic left ventricle training predicted death/transplantation, development of moderate-to-severe morphologic left ventricle dysfunction, or both (P = .02). CONCLUSIONS: The early results of the double-switch procedure in patients whose morphologic left ventricle required training compare favorably with those of patients whose morphologic left ventricle required no training. There is an increased risk of deterioration of morphologic left ventricle function over time in patients whose morphologic left ventricle requires training, and these patients need to be followed up regularly to detect this.