Pulmonary vein edema in a patient undergoing coronary artery bypass graft surgery and concomitant radiofrequency ablation for chronic atrial fibrillation

The syndrome of pulmonary vein stenosis characterized by pulmonary hypertension, dyspnea on exertion, and right heart failure, is a well-described complication of percutaneous ablation approaches, but has not been described with surgical approaches. We describe the case of a patient who developed localized edema at the pulmonary vein-left atrial junction after undergoing intraoperative radiofrequency ablation for chronic atrial fibrillation as part of CABG for severe triple vessel disease. The pulmonary vein edema resolved within 10 months suggesting that it may be a clinically silent and self-resolving phenomenon.     

Carto指引下环肺静脉导管消融术的达终点靶点分析及临床评价

目的:探讨环肺静脉导管消融术(CPVI)达终点部位及其分布规律,更有效地指导其达到肺静脉电隔离。方法:96例药物治疗无效的有临床症状的心房颤动患者。通过Carto电解剖标测系统三维标测指引下行CPVI。消融终点为完成环状消融线并实现肺静脉电位消失即肺静脉电隔离。结果:96例患者CPVI时记录到的消融靶点达终点部位203处,包括左侧肺静脉114处,位于左前上(45处,39.5%),左前下(26处,22.8%)和左前中(16处,14.0%);环右侧肺静脉89处,分别位于右后上(40处,44.9%)和右中下(27处,30.3%)。9例再次行CPVI的电隔离者与上述部位一致。手术并发症包括:1例少量心包积液,1例顽固性呃逆,血气胸1例,迷走反射2例,2例颈部血肿。结论:CPVI达终点部位有一定规律,多见于左侧肺静脉消融线前壁和右侧肺静脉消融线后壁,可为再次消融有效提示消融达终点部位的大体位置。     

Differentiation of atrial and pulmonary vein potentials recorded circumferentially within pulmonary veins

INTRODUCTION: Accurate discrimination of atrial and pulmonary vein potentials recorded circumferentially within the pulmonary veins is important when performing segmental isolation of the pulmonary veins in patients with atrial fibrillation. METHODS AND RESULTS: Twenty patients with paroxysmal atrial fibrillation underwent pulmonary vein mapping with a decapolar Lasso catheter during sinus rhythm and during pacing in the distal coronary sinus and left atrial appendage. Bipolar and unipolar electrograms were recorded within the left superior, right superior, and left inferior pulmonary veins. The atrial potentials were larger in the left pulmonary veins than in the right superior pulmonary vein, whereas the pulmonary vein potentials in the superior pulmonary veins were larger than in the left inferior pulmonary vein. The atrial and pulmonary vein potentials usually were readily distinguished during sinus rhythm in the right superior pulmonary vein. Characteristic distribution and morphologies of the atrial potentials as well as the response to distal coronary sinus and left atrial appendage pacing were useful for differentiating the atrial and pulmonary vein potentials in the left pulmonary veins. CONCLUSION: Atrial and pulmonary vein potentials recorded circumferentially within the pulmonary veins have characteristic features that are useful in distinguishing them from each other. In the left pulmonary veins, discrimination of the atrial and pulmonary vein potentials is aided by coronary sinus or left atrial appendage pacing.     

Catheter based treatments for fibrosing mediastinitis

Fibrosing mediastinitis is a rare, often debilitating and potentially lethal disease characterized by an exuberant fibroinflammatory response within the mediastinum. Patients typically present with insidious symptoms related to compression of adjacent structures including the esophagus, heart, airways, and cardiac vessels. Fibrosing mediastinitis is most often triggered by Histoplasmosis infection; however, antifungal and anti‐inflammatory therapies are largely ineffective. While structural interventions aimed at alleviating obstruction can provide significant palliation, surgical interventions are challenging with high mortality and clinical experience with percutaneous interventions is limited. Here, we will review the presentation, natural history, and treatment of fibrosing mediastinitis, placing particular emphasis on catheter‐based therapies.     

Effect of heating on pulmonary veins: how to avoid pulmonary vein stenosis

INTRODUCTION: The success of radiofrequency energy catheter ablation for the treatment of patients with paroxysmal or chronic atrial fibrillation has been complicated by postablation development of pulmonary vein (PV) stenosis. The acute effect of heat on PV structure has not been well characterized. The aim of this study was to characterize the effects of hyperthermic exposure on PVs and to determine the critical temperature at which PV stenosis would be observed. METHODS AND RESULTS: The main PVs of acutely explanted canine hearts were identified, isolated, and dissected from the left atria. Measurements of the diameter of 3-mm PV rings were obtained at baseline and after hyperthermic exposure at 60 degrees C, 65 degrees C, 70 degrees C, and 80 degrees C. Mechanical behavior of PVs was studied by examining the stress-strain relationship of each PV specimen after heat exposure at different temperature settings. Twenty-eight PVs samples from 15 dogs (1-3 PVs/dog) were obtained and had a mean circumference of 8.7 +/- 2.3 mm at baseline. After heating to 60 degrees C, 65 degrees C, 70 degrees C, and 80 degrees C, the mean PV circumference was 9.2 +/- 2.3 mm (P = NS vs baseline), 6.8 +/- 2.3 mm (P < 0.0001), 4.2 +/- 1.5 mm (P < 0.0001), and 4.2 +/- 0.8 mm (P < 0.0001), respectively. The stress-strain curves of PV specimens were shifted to the left upon exposure to higher temperatures, indicating loss of compliance of PVs due to heat exposure. Histology showed loss of typical collagen matrix above 60 degrees C. CONCLUSION: Significant acute heat-induced contraction of PVs at zero-tension state was observed between 60 degrees C and 65 degrees C. This change was associated with collagen denaturation.     

Maintenance of atrial fibrillation by pulmonary vein tachycardia with ostial conduction block: evidence of an interpulmonary vein electrical connection

We report a case of a 56-year-old man with paroxysmal atrial fibrillation who underwent segmental, ostial pulmonary vein (PV) isolation while in arrhythmia. During isolation of the left superior PV (LSPV), organized electrical activity was seen within the vein, suggestive of a PV tachycardia with a cycle length of 90 ms. Simultaneously, organized electrical activity with a cycle length of 180 ms was seen in the left inferior PV (LIPV), suggestive of 2:1 conduction between the LSPV and the LIPV. Isolation of the LIPV resulted in conversion to sinus rhythm, while confirming isolation of the LSPV by the presence of ongoing PV tachycardia in this vein. This case demonstrates a direct electrical connection between the ipsilateral left PVs, leading to maintenance of atrial fibrillation.     

Comparison of conventional and cutting balloon angioplasty for congenital and postoperative pulmonary vein stenosis in infants and young children

Background: Pulmonary vein stenosis (PVS) is a rare and often lethal condition in children. The optimal treatment for congenital and postoperative PVS is unknown. Methods and Results: We compared outcomes of conventional balloon angioplasty performed for PVS from 1999 to 2003 against cutting balloon angioplasty performed from 2004 to 2007. A total of 100 previously undilated pulmonary veins in 54 patients were studied: 48 veins dilated with conventional balloons and 52 with cutting balloons. Acute results included significantly reduced gradients and increased lumen diameters with both treatments. Acutely, cutting balloon angioplasty and conventional angioplasty yielded similar relative reduction of the PVS gradient (median 78% vs. 63%, P = 0.08) and increase in lumen diameter (median 77% vs. 59%, P = 0.07). There was one procedural death of a critically ill infant, and four cardiac arrests, but no adverse events necessitating surgical intervention. Survival free from reintervention was poor in both groups, and shorter in the cutting balloon group (73% at 1 month, 11% at 6 months, and 4% at 1 year) than in the conventional angioplasty group (77% at 1 month, 35% at 6 months, and 23% at 1 year; P = 0.01). Conclusions: Both conventional and cutting balloon angioplasty were effective at decreasing gradient and increasing lumen size acutely in patients with congenital and postoperative PVS, but reintervention was common with both treatments. Both methods of angioplasty provided limited benefit, and neither was curative for this complex disease. © 2010 Wiley‐Liss, Inc.     

Identification of pulmonary vein potentials by differential site atrial pacing in patients with paroxysmal atrial fibrillation: enhanced detection by pulmonary vein pacing

INTRODUCTION: Pulmonary vein (PV) isolation may cure paroxysmal atrial fibrillation (PAF); however, identification of PV potentials may be difficult in sinus rhythm. Studies have suggested that atrial pacing may improve the identification of PV potentials. METHODS AND RESULTS: In 25 consecutive patients who underwent PV isolation for PAF, the results of pacing from the distal PV, distal and proximal coronary sinus, and high right atrium compared to sinus rhythm were analyzed to determine the most effective pacing site for identification of PV potentials. The percentage of confirmed PV potentials and the longest interval between atrial and PV potentials in each PV were compared during differential site pacing and sinus rhythm. PV potentials were confirmed in 63 (82%) of 77 PVs that could be mapped during the complete pacing protocol and during sinus rhythm. Distal PV pacing identified significantly more PV potentials (left upper pulmonary vein [LUPV] 100%, left lower pulmonary vein [LLPV] 84%, right upper pulmonary vein [RUPV] 80%, right lower pulmonary vein [RLPV] 53%) compared to other pacing sites and sinus rhythm. Among atrial pacing sites, those ipsilateral to the PV being mapped were the most effective for identifying PV potentials. The intervals between atrial and PV potentials were significantly longer during distal PV pacing than pacing at other sites (LUPV 81.6 +/- 26.2 ms, LLPV 61.4 +/- 26.1 ms, RUPV 59.7 +/- 33.2 ms, RLPV 39.7 +/- 26.7 ms). CONCLUSION: (1) Distal PV pacing was most effective for identifying PV potentials. (2) The interval between atrial and PV potentials was longest during distal PV pacing.     

New cryotechnology for electrical isolation of the pulmonary veins

INTRODUCTION: Creation of radiofrequency lesions to isolate the pulmonary veins (PV) and ablate atrial fibrillation (AF) has been complicated by stenosis of the PVs. We tested a cryoballoon technology that can create electrical isolation of the PVs, with the hypothesis that cryoenergy will not result in PV stenosis. METHODS AND RESULTS: Lesions were created in 9 dogs (weight 31-37 kg). Cryoenergy was applied to the PV-left atrial (LA) interface. Data collected before and after ablation included PV orifice size, arrhythmia inducibility, electrogram activity, and pacing threshold in the PVs. Tissue examination was performed immediately after ablation in 3 dogs and after 3 months (4.8 +/- 1.0) in 6 dogs. After ablation there was no localized P wave activity in the ablation zone and no LA-PV conduction. Before ablation, the pacing threshold was 1.9 +/- 1.1 mA in each PV. After ablation, the pacing threshold increased significantly to 7.2 +/- 1.8 mA, or capture was not possible. Burst pacing did not induce any sustained arrhythmias. Most dogs had hemoptysis during the first 24 to 48 hours. Acute tissue examination revealed hemorrhagic injury of the atrial-PV junction that extended into the lung parenchyma. After recovery, the lesions were circumferential and soft with no PV stenosis. Histologic examination revealed fibrous tissue with no PV-LA interface thickening. CONCLUSION: This new cryoballoon technology effectively isolates the PVs from LA tissue. No PV stenosis was noted. Acute tissue hemorrhage and hemoptysis are short-term complications of this procedure. After 3 months of recovery, cryoablated tissue exhibits no collagen or cartilage formation.     

Percutaneous pulmonary vein stenosis angioplasty complicated by rupture: Successful stenting with a polytetrafluoroethylene‐covered stent

A 47‐year‐old‐man with prior pulmonary vein (PV) isolation for atrial fibrillation developed progressive shortness of breath and was found to have total occlusion of the left lower and significant stenosis in left upper PV. A ventilation/perfusion scan showed decreased left lung perfusion. Percutaneous PV stenosis angioplasty was complicated by the rupture of left lower PV with pericardial tamponade; successful stenting with a polytetrafluoroethylene‐covered stent was performed. Follow‐up studies at nine months showed patency of both veins with a normal ventilation perfusion scan. In this article, we will discuss acquired PV stenosis following PV isolation, percutaneous PV intervention, and the literature supporting the procedure. © 2014 Wiley Periodicals, Inc.     

Reentry in a pulmonary vein as a possible mechanism of focal atrial fibrillation

The case of an 18-year-old woman with recurrent idiopathic catecholamine-sensitive paroxysmal atrial fibrillation is reported. Recordings of multiple initiations of atrial fibrillation at the proximal part of the right superior pulmonary vein suggested local reentry in the vein as the mechanism of atrial fibrillation. A single radiofrequency pulse delivered at this site resulted in definite cure of the arrhythmia.     

Preoperative balloon dilatation of obstructed total anomalous pulmonary venous connection in a neonate.

Prompt recognition and early surgical correction are mandatory in neonates presenting with obstructed total anomalous pulmonary venous connection (TAPVC). Preoperative balloon angioplasty of obstructed TAPVC in a sick neonate is rarely reported. We describe successful short-term palliation with balloon angioplasty of a critically ill neonate with obstructed supracardiac TAPVC.     

Comparison of stent versus balloon angioplasty for pulmonary vein stenosis complicating pulmonary vein isolation

Introduction: Pulmonary vein stenosis (PVS) is a rare but significant complication of pulmonary vein isolation (PVI). Dilation and stent angioplasty have been described but not compared.
Methods and Results: All percutaneous interventions for PVS complicating PVI between December 2000 and March 2007 were reviewed. Acute success, defined as post-intervention stenosis ≤30%, and long-term outcome of dilation versus stent angioplasty were compared. Freedom from restenosis was defined as freedom from repeat intervention. Overall outcome for all interventions was examined. We studied 34 patients with 55 stenotic veins followed for a mean of 25 months. Dilation was performed in 39 veins and stenting in 40 veins (16 primarily, 24 after dilation restenosis). Acute success and restenosis rates were 42% and 72% for dilation versus 95% (P < 0.001) and 33% for stenting. Time to restenosis was greater for stent angioplasty (P = 0.003). Stents ≥10 mm in diameter had lower restenosis than smaller stents. Risk factors for restenosis included small reference vessel diameter and longer time from PVI to intervention for PVS. All but two patients experienced improvement (n = 10) or resolution of symptoms (n = 22). The mean percent stenosis decreased from 82% to 21% for the entire cohort and mean flow to the lung quadrant increased from 10% to 17%.
Conclusion: Stent angioplasty results in less restenosis than dilation, particularly for stents ≥10 mm. Early referral may improve long-term patency by minimizing reference vessel atrophy. Most patients with PVS post-PVI can be improved symptomatically with catheter intervention.     

Isolated congenital left-sided pulmonary vein stenosis in an adult patient misdiagnosed as primary pulmonary hypertension

Pulmonary vein stenosis (PVS) is a rare condition, seen usually in association with congenital heart disease or secondary to various acquired causes. Isolated PVS, in adults, especially in absence of congenital heart disease is extremely uncommon. We report PVS of left sided pulmonary veins in an 18-year-old male, who had been till then diagnosed as primary pulmonary hypertension (PPH).     

Spontaneous and induced pulmonary vein tachycardia after pulmonary vein isolation.

A case is reported of recurrence of paroxysmal atrial fibrillation after pulmonary vein ablation. A second procedure achieved isolation of three pulmonary veins and showed persistence of pulmonary vein tachycardia in one with implications concerning the electrophysiology of atrial fibrillation.