Approach For Pulmonary Vein Isolation Research Articles

Mechanism of Regular Atrial Tachyarrhythmias During Combined Pulomonary Vein Isolation and Complex Fractionated Electrogram Ablation in Patients With Atrial Fibrillation

Atrial tachyarrhythmias (ATA) frequently develop during catheter ablation of atrial fibrillation (AF), but the mechanism of ATA during combined pulmonary vein isolation (PVI) and complex fractionated electrogram-guided ablation (CFEA) has not been reported. This study involved 105 patients with symptomatic, drug-refractory AF. After PVI, CFEA was performed in the left/right atrium if AF remained inducible in paroxysmal AF (PAF) or persisted in persistent AF (PeAF). For the 70 PAF patients, PVI alone rendered AF non-inducible in 29 patients (41.4%), and converted inducible AF into inducible atrial flutter (AFl) in 10 patients (14.3%). For the remaining 31 PAF patients, additional CFEA rendered AF non-inducible in 11 patients (15.7%), whereas only AFl was inducible in 11 patients (15.7%). For 35 PeAF patients, PVI and CFEA converted AF into sinus rhythm in 2 (5.7%) and into AFl in 21 (60.0%) patients, while AF persisted in 12 patients (34.3%). The mechanism of ATA was focal (20/114, 17.5%), roof-dependent (20/114, 17.5%), peri-mitral (33/114, 28.9%), cavotricuspid isthmus-dependent (34/114, 29.8%) AFl or unknown (7/114, 6.1%). Successful ablation was achieved in 93/114 (81.6%) tachycardias. The major mechanism of ATA during the combined approach of PVI and CFEA is macroreentry around large anatomic obstacles such as the pulmonary vein or the mitral or tricuspid annuli.

Acute Effects and Long-Term Outcome of Pulmonary Vein Isolation in Combination With Electrogram-Guided Substrate Ablation for Persistent Atrial Fibrillation

Complex fractionated atrial electrographic (CFAE) catheter ablation is a new approach for the treatment of atrial fibrillation (AF). It is unclear if acute results of this approach correspond to long-term outcome. The purpose of this study was to prospectively assess acute and long-term successes of an ablation approach combining pulmonary vein isolation (PVI) and ablation of CFAE areas for treatment of persistent AF. PVI and ablation of CFAE areas were performed in 35 patients with persistent AF (30 men, 57+/-9 years of age). At the end of the ablation procedure AF had terminated in 23 of 35 patients (66%) by conversion to sinus rhythm (8 of 23 patients, 35%) or organization to atrial tachycardia (15 of 23 patients, 65%). AF persisted in 12 of 35 patients (34%). At the end of the follow-up period (19+/-12 months), sinus rhythm was present in 26 of 35 patients (74%), including 9 patients with a repeat procedure. This group of 26 patients consisted of 7 of 8 patients (88%) with acute sinus rhythm after the first ablation, 11 of 15 patients (73%) with organization, and 8 of 12 patients (66%) with ongoing AF (p=0.32). In conclusion, a combined approach of PVI and CFAE ablation in persistent AF leads to acute AF termination in 66% and long-term maintenance of sinus rhythm in 74% of cases. However, long-term outcome was not predictable by acute results of the ablation procedure.

Achievement of Pulmonary Vein Isolation in Patients Undergoing Circumferential Pulmonary Vein Ablation: A Randomized Comparison Between Two Different Isolation Approaches

Circumferential pulmonary vein ablation (CPVA) with the endpoint of pulmonary vein (PV) isolation has been developed as an effective therapy for atrial fibrillation (AF). This endpoint can be achieved either by closing gaps along circular lines or by segmental PV isolation inside the circular lines after creation of initial CPVA lesions. We investigated whether the clinical outcome depends on the PV isolation approach used during the first-time CPVA procedure. One hundred consecutive patients (69 male; age, 56.7 +/- 11.6 years) who underwent first-time CPVA for treatment of symptomatic AF were enrolled. PV isolation was randomly achieved either by CPVA alone (aggressive CPVA [A-CPVA] group, n = 50) or by a combination of CPVA with segmental PV ostia ablation (modified CPVA [M-CPVA] group, n = 50). Recurrence of atrial tachyarrhythmias (ATa) within 3 months after the initial procedure occurred in 30 patients (60%) in the M-CPVA group and in only 15 patients (30%) in the A-CPVA group (P < 0.01). ATa relapse after the first 3 months was detected in 21 patients (42%) in the M-CPVA group, compared with 9 patients (18%) in the A-CPVA group (P = 0.01). At 13 +/- 4 months, patients treated by the A-CPVA approach had greater freedom from ATa recurrence than patients who underwent M-CPVA (P = 0.01). The M-CPVA approach was the only independent predictor associated with procedural failure (RR 0.318; 95% CI 0.123-0.821; P = 0.02). When PV isolation is the endpoint of CPVA, the efficacy of the A-CPVA approach is better than that of M-CPVA.

Thoracoscopic ablation for treatment of atrial fibrillation: a 2-port approach.

We describe epicardial ablation using a 2-port, right-sided, thoracoscopic approach for pulmonary vein isolation on the beating heart in the treatment of atrial fibrillation. Our early success rate with this procedure for the epicardial lesion pattern is 86%. Utilizing new ablation energy sources, such as laser and microwave, this port access approach offers surgeons a true minimally invasive, safe, and efficacious option that will support the lone treatment of atrial fibrillation.

New Approach to Pulmonary Vein Isolation for Atrial Fibrillation Using a Multielectrode Basket Catheter

Pulmonary vein (PV) isolation using a circular catheter creates an entrance block from the left atrium (LA) to the PV, which eliminates paroxysmal atrial fibrillation (PAF). A new approach to PV isolation during distal PV pacing is to use a basket catheter. Fifty consecutive patients with PAF underwent basket-catheter-guided PV isolation. PV pacing was performed from the distal electrode pair of the basket catheter. The exit breakthrough point was targeted for segmental PV isolation. The endpoint was the elimination of bidirectional PV - LA conduction. A repeat ablation procedure was performed in 12 of 14 patients who had recurrence of AF. The recovery of PV -LA conduction was noted in 24 of the 48 PVs, and 5 PVs (21%) had unidirectional block. At 12 months, 80% of patients were free of AF without antiarrhythmic drugs. No PV stenosis >50% was detected at 12 months after the procedure. This new approach for PV isolation during distal PV pacing using a basket catheter is useful for confirming bidirectional PV - LA conduction block. PV isolation that creates not only an entrance block but also an exit block at the PV - LA junction may be required to cure paroxysmal AF.

Comparison of 2 Mapping Strategies for Pulmonary Vein Isolation

Pulmonary vein (PV) isolation using a circular catheter (CC) creates an entrance block from the left atrium (LA) to PV to eliminate paroxysmal atrial fibrillation (PAF). We describe a new approach for PV isolation during distal PV pacing using a basket catheter (BC). The purpose of the present study was to compare 2 mapping strategies for PV isolation. Of 100 consecutive patients with PAF, 50 underwent CC-guided PV isolation and 50 underwent BC-guided PV isolation. During CC-guided ablation, the endpoint was the elimination of PV potentials based on the entrance block from the LA to PV. During BC-guided ablation during distal PV pacing, the endpoint was the elimination of bidirectional PV-LA conduction. At 12 months, 62% of patients who underwent CC ablation and 80% of patients who underwent BC ablation were free of symptomatic PAF without the use of antiarrhythmic drugs (p<0.05). The incidence of mild (<50%) PV stenosis in BC ablation was significantly lower than that in CC ablation (12 vs 24%, p<0.01). This new approach for PV isolation during distal PV pacing using BC is useful for confirming a bidirectional PV-LA conduction block and is more effective than CC ablation.

Técnica cirúrgica simplificada pode ser eficaz no tratamento da fibrilação atrial crônica secundária a lesão valvar mitral?

INTRODUÇÃO: Fibrilação atrial tem sido tratada pelo procedimento do Labirinto (Cox) e suas modificações. Há, no entanto, evidências de que o isolamento dos óstios das veias pulmonares ou exclusão do átrio esquerdo poderia ser eficaz para este fim. CASUÍSTICA E MÉTODOS: Avaliamos os resultados iniciais da técnica simplificada de isolamento cirúrgico dos óstios das veias pulmonares para tratar fibrilação atrial crônica em pacientes operados por lesão valvar mitral. Foram tratados 7 pacientes por esta técnica (grupo IVP) e comparados com série prévia de 57 casos submetidos a cirurgia do Labirinto (Cox 3). RESULTADOS: A idade média foi de 49±8 anos vs 49±11 anos, (IVP vs. Cox3), sendo 71% e 72% (IVP vs. Cox 3) do sexo feminino. Dimensões do átrio esquerdo 5,5±0,7 cm vs. 6,0±1,1 cm (IVP vs. Cox 3). Fração de ejeção ventricular 63±10% vs. 64±6% (IVP vs. Cox 3). Tempo CEC 91±33 min vs. 104±29 min (IVP vs. Cox 3). Tempo de isquemia71±23 min vs. 83±26 min (IVP vs. Cox 3). Ritmo pós-operátório sinusal/atrial n(%): 6(86) vs. 46(80) (IVP vs. Cox 3). Ritmo marcapasso n(%):1 (14) vs. 4 (7) (IVP vs. Cox 3). Fibrilação atrial n(%): 0 vs. 7 (13) (IVP vs. Cox 3). CONCLUSÕES: Resultados iniciais mostram reversão a ritmo sinusal na maioria dos casos em ambos procedimentos e manutenção do ritmo a longo prazo. Foi iniciado estudo prospectivo randomizado para avaliar o IVP comparativamente ao procedimento Cox 3.