Approaching a paradigm shift: endoscopic ablation of lone atrial fibrillation on the beating heart.

BACKGROUND: Percutaneous catheter ablation has been the preferred treatment strategy for many patients with symptomatic drug-refractory atrial fibrillation (AF). However, incomplete ablation lines and varying success rates remain a problem in certain subgroups. This article evaluates the feasibility and efficacy of endoscopically performed left atrial ablation in patients with lone AF. METHODS: Epicardial bipolar radiofrequency ablation was performed on the beating heart through a bilateral endoscopic approach in 89 consecutive patients with lone AF. This included isolation of the pulmonary veins using a clamp; isolation of the posterior left atrial wall, including a trigonal line to the aortic noncoronary sinus using a linear ablation device; and resection of the left atrial appendage (LAA). Preoperative, perioperative, and postoperative data were collected prospectively and included questionnaires and 24-hour Holter monitoring at 6 and 12 months and annually thereafter. RESULTS: Mean follow-up was 12±6 months (range, 4-28 months). No patients were lost to follow-up. Mean duration of AF was 6.4±5.7 years, with 35% paroxysmal AF and 65% persistent or long-standing persistent AF. Mean operation time was 180±43 minutes. There were no deaths, no conversion to sternotomy, and no early or late stroke. Freedom from AF was 88%, 90%, and 90% at 6, 12, and 24 months, respectively. Freedom from AF without antiarrhythmic drugs was 71%, 82%, and 90% at 6, 12, and 24 months, respectively. CONCLUSIONS: Endoscopic radiofrequency ablation on the beating heart reveals high success rates with low procedure-related morbidity. For improvement of future treatment strategies, a randomized trial is advisable to compare this procedure with catheter ablation in certain patient subgroups.

Survival and reintervention after neonatal repair of truncus arteriosus with valved conduit.

OBJECTIVE: Neonatal primary repair has progressively become the treatment of choice for truncus arteriosus with encouraging survival. However, use of valved conduits to reconstruct the right ventricular outflow tract (RVOT) inevitably induces reintervention. This study estimates survival and rate of catheter-interventional and surgical reinterventions. METHODS: Thirty-five consecutive neonates who underwent truncus repair with 27 homografts and 8 Contegras from 1987 to 2007 were studied. Interrupted aortic arch (IAA) was associated in nine patients. Actuarial survival and freedom from reintervention were evaluated according to Kaplan-Meier method. RESULTS: Five patients died early after repair. Two died late and one death was related to reintervention. Survival was 91.9%+/-5.4% from postoperative month 2 onwards when IAA was not associated and 41.7%+/-17.3% from month 4 in IAA presence. During a median follow-up of 68 months (range 1-180 months), 42 reinterventions (of which 17 reoperations) were performed in 21 patients. Rate of reintervention was 2.6 per early survivor per 10 years. RVOT obstruction constituted the main indication: branch pulmonary arteries often being involved (n=25). Uncommon indication was subaortic stenosis (n=3), aortic arch obstruction (n=2) and truncal valve regurgitation (n=2). At year 10, freedom from first, second and third reintervention was 17.9 %+/-8.1%, 46.1%+/-10.6% and 81.9%+/-9.5%, respectively. Sixteen first conduits were explanted. Freedom from first conduit replacement was 87.5%+/-6.8%, 64.1%+/-10.2% and 39.5%+/-10.7% at year 1, 3 and 5, respectively. Homografts enjoyed higher durability than Contegras. CONCLUSION: Neonatal repair of truncus arteriosus results in high survival, the only risk being IAA association. The rate of reintervention is heavily influenced by stenosis of branch pulmonary arteries.

Compared fate of small-diameter Contegras and homografts in the pulmonary position.

OBJECTIVE: This study analyzes whether small-diameter Contegras behave in the same way as small-diameter homografts, when implanted for the first time in pulmonary position. METHODS: Small-diameter conduits include 12 and 14 mm Contegras and 8-14 mm homografts. Graft dysfunction is defined as right ventricular outflow tract obstruction with peak echo-Doppler gradient>40 mmHg, or grade III/IV graft regurgitation. Graft failure is defined as need for conduit replacement or need for catheter or surgical reintervention. Thirty-eight patients who received small Contegras (n=25) and small homografts (n=13) from October 2002 to end December 2006 were studied. The most frequent indication was pulmonary atresia and ventricular septal defect (n=20; 10 associated with major aorto-pulmonary collateral arteries), followed by truncus arteriosus (n=12). Most patients' characteristics were comparable except that recipients of homografts were smaller (p for body area=0.014). Survival, freedom from graft dysfunction, failure and explantation were estimated by the Kaplan-Meier method. The log-rank test was used to compare outcomes. RESULTS: There were three early and four late deaths. No death was graft related. Survival was 80+/-8.2% for patients with Contegras and 77+/-11.7% for those with allografts: p=0.82. Mean follow-up duration is 22+/-16 months. Freedom from dysfunction for Contegras conduits decreased in the first 6 months and stabilized at 58+/-11% from month 14. For homografts it decreased only 1 year after implantation, down to 35+/-19.7% from month 31: p=0.61. Freedom from Contegras failure diminished the first 16 months to level out at 57+/-13%. No homograft failed the first 2 years. With a p-value of 0.14, homografts tended to fail less frequently. Five grafts were explanted. Freedom from explantation was similar (p=0.98): 90+/-6.7% for Contegras and 75+/-21.6% for homografts at year 3. CONCLUSION: In the first 4 years after pulmonary implantation of small-diameter Contegras and homografts, the fate of both conduits was statistically similar, in spite of different behavior. As Contegras is 'off-the-shelf' available, it constitutes a sound alternative to homograft for right ventricular outflow tract reconstruction in neonates and infants.