Acquired pulmonary vein stenosis after radiofrequency ablation treated by angioplasty and stent implantation

Assessment and Management of Pulmonary Vein Occlusion After Atrial Fibrillation Ablation

OBJECTIVES

This study sought to evaluate the sensitivity of noninvasive imaging in the assessment of severely stenosed and occluded pulmonary veins, and examine clinical outcomes following percutaneous intervention.

BACKGROUND

PV stenosis (PVS) is a rare complication of atrial fibrillation ablation, but is associated with significant morbidity. Patients present with nonspecific pulmonary symptoms that can result in delayed diagnosis and progression to PV occlusion. The assessment and management of PV occlusion has rarely been described.

METHODS

This was a prospective observational study performed from 2000 to 2014.

RESULTS

Computed tomography identified 124 patients with severe PVS, including 46 patients with at least 1 occluded vein. Patients with PV occlusion more frequently presented with cough (64.1% vs. 32.8%; p = 0.002) and hemoptysis (39.1% vs. 14.1%; p = 0.0015) and were more likely to have pulmonary parenchymal consolidation (77.3% vs. 41.7%; p = 0.0002). Intervention was attempted in 65 occluded veins and a residual microchannel was identified in 22 (34.0%). Balloon angioplasty was performed in 11, and 11 were treated with stenting. Over 3 years the rates of restenosis were similar for patients with PVS and PV occlusion (47.0% vs. 35.0%; p = 0.24). Among patients with PV occlusion, stenting significantly reduced the rate of restenosis (hazard ratio: 3.97; 95% confidence interval: 1.14 to 13.85; p = 0.03).

CONCLUSIONS

Veins deemed occluded on noninvasive imaging require invasive characterization, as residual microchannels may be present in one-third of patients. In patients with a microchannel, intervention can be performed with either balloon angioplasty or stenting. Recurrence remains a common problem; however, stenting significantly reduces the rate of subsequent restenosis.

Outcomes and Management of Patients With Severe Pulmonary Vein Stenosis From Prior Atrial Fibrillation Ablation

BACKGROUND

Pulmonary vein (PV) stenosis remains a feared complication of atrial fibrillation ablation. Little is known about outcomes in patients with severe PV stenosis, especially about repeat ablations.

METHODS

In 10 368 patients undergoing atrial fibrillation ablation (2000-2015), computed tomography scans were obtained 3 to 6 months after ablation. The clinical outcomes in severe PV stenosis were determined.

RESULTS

Severe PV stenosis was diagnosed in 52 patients (0.5%). This involved mostly the left superior PV (51% of severely stenosed veins). Percutaneous interventions were performed in 43 patients, and complications occurred in 5: 3 PV ruptures, 1 stroke, and 1 phrenic injury. Over a median follow-up of 25 months, 41 (79%) patients remained arrhythmia free. Repeat ablation was performed in 15 patients (7 from the main series and 8 from prior ablation at other institutions); of whom 10 had PV stents in place. Conduction recovery was noted in all but 2 of the stenosed or stented PVs, and areas with recovery were targeted with antral ablation. Lasso entrapment within stents occurred in 2 patients but eventually freed without complications. After redo ablation, preplanned stenting was performed in 3 patients and computed tomographic scans showed progression of concomitant stenoses in 1 patient (moderate to severe). No procedure-related deaths occurred.

CONCLUSIONS

The incidence of severe PV stenosis is low but remains associated with significant morbidity. In patients with recurrent arrhythmia, conduction recovery at the stenosed or stented veins is common. Care must be taken to ablate antrally to avoid stenosis progression. In patients with prior PV stents, we suggest to avoid using Lasso.

Severe Pulmonary Vein Stenosis Resulting From Ablation for Atrial Fibrillation

Background:

The frequency of pulmonary vein stenosis (PVS) after ablation for atrial fibrillation has decreased, but it remains a highly morbid condition. Although treatment strategies including pulmonary vein dilation and stenting have been described, the long-term impacts of these interventions are unknown. We evaluated the presentation of severe PVS, and examined the risk for restenosis after intervention using either balloon angioplasty (BA) alone or BA with stenting.

Methods:

This was a prospective, observational study of 124 patients with severe PVS evaluated between 2000 and 2014.

Results:

All 124 patients were identified as having severe PVS by computed tomography in 219 veins. One hundred two patients (82%) were symptomatic at diagnosis. The most common symptoms were dyspnea (67%), cough (45%), fatigue (45%), and decreased exercise tolerance (45%). Twenty-seven percent of patients experienced hemoptysis. Ninety-two veins were treated with BA, 86 were treated with stenting, and 41 veins were not treated. A 94% acute procedural success rate was observed and did not differ by initial management. Major procedural complications occurred in 4 of the 113 patients (3.5%) who underwent invasive assessment, and minor complications occurred in 15 patients (13.3%). Overall, 42% of veins developed restenosis including 27% of veins (n=23) treated with stenting and 57% of veins (n=52) treated with BA. The 3-year overall rate of restenosis was 37%, with 49% of BA-treated veins and 25% of stented veins developing restenosis (hazard ratio, 2.77; 95% confidence interval, 1.72–4.45; P <0.001). After adjustment for age, CHA2DS2-VASc score, hypertension, and the time period of the study, there was still a significant difference in the risk of restenosis for BA versus stenting (hazard ratio, 2.46; 95% confidence interval, 1.47–4.12; P <0.001).

Conclusions:

The diagnosis of PVS is challenging because of nonspecific symptoms and the need for dedicated pulmonary vein imaging. There is no difference in acute success by type of initial intervention; however, stenting significantly reduces the risk of subsequent pulmonary vein restenosis in comparison with BA.

How to identify and treat patient with pulmonary vein stenosis post atrial fibrillation ablation

PURPOSE OF REVIEW

The diagnosis of pulmonary vein stenosis, following catheter ablation of atrial fibrillation, potentially carries significant morbidity for affected patients. It is important that physicians remain aware of the entity and have an understanding of how to treat such patients. There has been controversy in how to assess patients following atrial fibrillation ablation, and how to treat asymptomatic patients with pulmonary vein stenosis. This article reviews the recently published data.

RECENT FINDINGS

The reported incidence of pulmonary vein stenosis is decreasing. Nonetheless, it may not be found if not sought, as even patients with severe pulmonary vein stenosis may be asymptomatic. Also, patients with symptoms may be misdiagnosed if pulmonary vein stenosis is not included in the differential diagnosis. Computed tomography (CT) and MRI have been shown to be the diagnostic modalities of choice. The treatment options for severe pulmonary vein stenosis and occlusion are primarily that of pulmonary vein angioplasty with or without stenting. Despite the observed rate of restenosis, patients derive benefit from pulmonary vein angioplasty.

SUMMARY

The best imaging modalities to assess for pulmonary vein stenosis are CT and MRI. Early intervention in symptomatic patients with severe pulmonary vein stenosis is warranted; in asymptomatic patients, the data suggest that such patients will also derive benefit.