Significance of Late Recurrence of Atrial Fibrillation during Long-Term Follow-Up after Pulmonary Vein Isolation

Background and Study Objective : Patients with paroxysmal or persistent atrial fibrillation (AF) can be treated by pulmonary vein (PV) isolation. Although the recurrence rate after the procedure is relatively high, the long-term outcomes after initially recurrence-free procedures remains unclear. We examined the rates of recurrence of AF after PV isolation.
Methods: Our study included 278 consecutive patients with drug-refractory AF (mean age = 53 ± 11 years, 228 men). PV isolation was based on the disappearance of PV potentials recorded from a circumferential catheter after segmental ostium ablation. Cavo-tricuspid isthmus lines and additional atrial lines were performed in 124 and 28 patients, respectively. Patients were monitored for a mean of 26 ± 11 months (range 12–56). Recurrence was defined as ≥1 episodes of symptomatic or asymptomatic AF >1 month after the procedure.
Results: A total of 120 (34) patients had ≥1 recurrence of AF >1 month after the procedure, of whom 14 (4) had a first recurrence >6 months after the procedure. There was a significantly higher recurrence rate among patients with persistent AF.
Conclusions : A relatively high AF recurrence rate was observed after PV isolation. AF may recur late after the ablation procedure, though the majority of recurrences occurred within 6 months after the first procedure. There were no differences in incidence or time of occurrence of late recurrences between patients with paroxysmal versus persistent AF.     

Feasibility of Pulmonary Vein Ostia Radiofrequency Ablation in Patients with Atrial Fibrillation: A Multicenter Study (CACAF Pilot Study)

STABILE, G., et al.: Feasibility of Pulmonary Vein Ostia Radiofrequency Ablation in Patients with Atrial Fibrillation: A Multicenter Study (CACAF Pilot Study) Radiofrequency (RF) catheter ablation has been proposed as a treatment of atrial fibrillation (AF). Several approaches have been reported and success rates have been dependent on procedural volume and operator's experience. This is the first report of a multicenter study of RF ablation of AF. We treated 44 men and 25 women with paroxysmal   (n = 40)   or persistent   (n = 29)   , drug refractory AF. Circular pulmonary vein (PV) ostial lesions were deployed transseptally, during sinus rhythm   (n = 42)   or AF  ( n = 26)   , under three-dimensional electroanatomic guidance. Cavo-tricuspid isthmus ablation was performed in 27 (40%) patients. The mean procedure time was   215 ± 76   minutes (93–530), mean fluoroscopic exposure   32 ± 14   minutes (12–79), and mean number of RF pulses per patient   56 ± 29   (18–166). The mean numbers of separate PV ostia mapped and isolated per patient were   3.9 ± 0.5   , and   3.8 ± 0.7   , respectively. Major complications were observed in 3 (4%) patients, including pericardial effusion, transient ischemic attack, and tamponade. At 1-month follow-up, 21 of 68 (31%) patients had had AF recurrences, of whom 8 required electrical cardioversion. After the first month, over a mean period of   9 ± 3   (5–14) months, 57 (84%) patients remained free of atrial arrhythmias. RF ablation of AF by circumferential PV ostial ablation is feasible with a high short-term success rate. While the procedure and fluoroscopic exposure duration were short, the incidence of major cardiac complications was not negligible. (PACE 2003; 26[Pt. II]:284–287)     

High-Density Circumferential Pulmonary Vein Mapping with a 20-Pole Expandable Circular Mapping Catheter

The differentiation of pulmonary vein (PV) electrograms from atrial far-field signals during PV isolation (PVI) for atrial fibrillation (AF) may be difficult. In addition, owing to highly variable PV ostial sizes, current fixed-diameter circular PV mapping catheters may not yield optimal electrograms. We evaluated an expandable, circular 15–25 mm diameter, 20-pole mapping catheter for PV mapping during sustained AF in 25 patients. After selective PV angiography to define the ostial position and size, the catheter was introduced into each PV and withdrawn to the most stable proximal position, with optimal wall contact ensured by progressive loop expansion. At each PV ostium, electrograms recorded at high resolution (HR) were compared with those recorded at a resolution similar to that of a standard 10-pole Lasso catheter. After PVI performed during ongoing AF, the presence of residual far-field potentials (FFP) under both set-ups was compared. We mapped 97 PV, including 4 pairs with common ostia. In the HR recordings, the PV potentials had greater amplitude (0.5 ± 0.1 vs 0.3 ± 0.1 mV, P = 0.001) and fragmentation, whereas left atrial FFP were minimized. After successful isolation of all PV, FFP were observed in 33% of left superior and 28% of left inferior PV on the HR recordings, compared to 66% and 61%, respectively under normal resolution. Catheter stability and optimal wall contact, in combination with HR electrograms can optimize circumferential PV mapping during AF and improve the discrimination of FFP postablation.     

Staged circumferential and ostial pulmonary vein ablation for the treatment of paroxysmal atrial fibrillation

BACKGROUND: Comparisons between segmental ostial disconnection of the pulmonary veins (PV) and circumferential ablation have produced conflicting results in patients with paroxysmal atrial fibrillation (AF). The aim of this study was to evaluate a staged ablation procedure, every step of which was assessed by means of AF inducibility. METHODS: Twenty-two patients with paroxysmal AF were subjected to three ablation stages during one session: (1) circumferential ablation around the PV ostia, (2) segmental ostial PV isolation, and (3) ablation of areas within the circumferential lines with fractionated electrograms or voltage >0.2 mV as well as linear ablation at the mitral isthmus and the left atrial roof. Endpoint of the procedure was noninducibility of AF at any stage. RESULTS: Average radiofrequency energy delivery, fluoroscopy, and procedure times were 43 +/- 11 minutes, 40 +/- 11 minutes, and 3.8 +/- 0.5 hours, respectively. At 6-months follow-up, four patients experienced recurrence of AF (18%), whereas two additional patients (9%) had left atrial arrhythmias not registered before the procedure. Ninety-five percent of the patients who did not have inducible AF (regardless of the stage of ablation at which noninducibility was achieved) were free of recurrent AF, as opposed to none of the patients in whom AF was inducible at the end of the procedure (log-rank test, P < 0.001). CONCLUSIONS: A staged ablation procedure combing circumferential and ostial PV ablation with AF noninducibilty as endpoint may result in high success rates without the need of prolonged ablation sessions in certain patients with paroxysmal atrial fibrillation.     

Transvenous catheter cryoablation for treatment of atrial fibrillation: results of a feasibility study

Pulmonary vein (PV) isolation using radiofrequency (RF) ablation can induce PV stenosis. Cryoablation may offer a safer alternative energy source for PV isolation. PV isolation with cryoablation was attempted in 31 patients with paroxysmal atrial fibrillation (AF). Event monitors were used to measure the AF episode burden. Serial spiral CT scans were obtained to monitor PV stenosis pre- and postcryoablation. Cryoablation was immediately successful for PV isolation in 29 of 31 patients (94%), with 5.9 +/- 1.2 months of follow-up. Additional RF ablation was performed for AF recurrences in seven patients. The remaining 22 patients with a single cryoablation procedure demonstrated a time-dependent, long-term reduction in the frequency of AF episodes. At 6 months of follow-up, 18 of 22 of cryo-treated only patients (82%) were free of symptomatic AF episodes, and antiarrhythmic drugs were discontinued in 12 of 22 patients. Serial spiral CT scans demonstrated no change in the cryo-treated PV ostial diameter. PV cryoablation was effective to control paroxysmal AF in most patients. Early recurrences of AF postcryoablation were common, though tended to resolve within 6 months postablation, consistent with a process of reverse atrial remodeling. Cryoablation of the PVs did not cause PV stenosis or other serious adverse events.     

Long-Term Results of Cryoablation with a New Cryoprobe to Eliminate Chronic Atrial Fibrillation Associated with Mitral Valve Disease

The purpose of this study was to examine the performance of a new cryoprobe in the treatment of chronic atrial fibrillation (AF) associated with mitral valve disease. The study included 66 patients undergoing mitral valve replacement. The mean AF duration was 9.0 ± 9.0 years and mean left atrial (LA) was diameter 57 ± 10 mm. Cryoablation (−60°C) was applied to four pulmonary vein (PV) orifices over 2–3 minute. The spherical tip (2-cm in diameter) of the cryoprobe is capable of ablating the left atrium near the PV, as well as the PV ostium with a single cryoablation. After cryoablation, mitral valve surgery or a combined surgical procedure were performed in 66 patients. There were no intraoperative complications. Sinus rhythm was restored in 60 patients (91%) immediately after the operation. Recurrent AF was treated with antiarrhythmic drugs and/or direct current cardioversion in 43 patients (72%). At discharge, 48 patients (72%) were in sinus rhythm. During a mean follow-up period of 31 ± 16 months, 40 patients (61%) were in sinus rhythm with (29) or without antiarrhythmic drugs (11). In patients in sinus rhythm at the end of the follow-up period, the duration of preoperative AF duration was significantly shorter (P < 0.05) and the preoperative LA diameter and cardiothoracic ratio were significantly smaller than in patients who were in AF (both for P < 0.005). Using this new cryoprobe, sinus rhythm was restored and maintained in 61% of patients with chronic AF and mitral valve disease with a 12–15 minute cryoablation procedure.     

Transvenous Catheter Cryoablation for Treatment of Atrial Fibrillation:

Pulmonary vein (PV) isolation using radiofrequency (RF) ablation can induce PV stenosis. Cryoablation may offer a safer alternative energy source for PV isolation. PV isolation with cryoablation was attempted in 31 patients with paroxysmal atrial fibrillation (AF). Event monitors were used to measure the AF episode burden. Serial spiral CT scans were obtained to monitor PV stenosis pre- and postcryoablation. Cryoablation was immediately successful for PV isolation in 29 of 31 patients (94%), with 5.9 ± 1.2 months of follow-up. Additional RF ablation was performed for AF recurrences in seven patients. The remaining 22 patients with a single cryoablation procedure demonstrated a time-dependent, long-term reduction in the frequency of AF episodes. At 6 months of follow-up, 18 of 22 of cryo-treated only patients (82%) were free of symptomatic AF episodes, and antiarrhythmic drugs were discontinued in 12 of 22 patients. Serial spiral CT scans demonstrated no change in the cryo-treated PV ostial diameter. PV cryoablation was effective to control paroxysmal AF in most patients. Early recurrences of AF postcryoablation were common, though tended to resolve within 6 months postablation, consistent with a process of reverse atrial remodeling. Cryoablation of the PVs did not cause PV stenosis or other serious adverse events.     

Nonpulmonary Vein Foci:

Though the majority of foci triggering atrial fibrillation (AF) have been mapped to the pulmonary veins (PV), recurrence of paroxysmal AF after isolation of all four pulmonary veins indicates the presence of other foci. In a series of 160 consecutive patients who underwent PV ablation, endocardial mapping of AF and ectopy recurring after PV isolation was performed. Thirty-six patients (24%) had a total of 85 non-PV foci; 39 were mapped to the ostia of ablated PVs, 30 to the posterior left atrium (LA), 5 to other parts of the LA, 5 to the right atrium (RA), 4 to the coronary sinus (CS), and 3 to the superior vena cava (SVC) (including one persistent left SVC). Mapping was confirmed by successful ablation. At least 16 foci could not be localized and after a follow-up of 8 ± 6 months, 68% of patients were free of AF without any antiarrhythmic treatment. The occurrence of non-PV foci correlated with recurrence of AF, perhaps as a correlate of insufficient ostial ablation. These data reinforce the requirement for more proximal disconnection of the PVs by performing ablation within the LA. In patients with non-PV foci that are difficult to map conventionally, the use of surface ECG data, or multielectrode contact or noncontact mapping arrays, or substrate modifying/excluding ablation may be helpful in ablating these foci and therefore eliminating AF. (PACE 2003; 26[Pt. II]:1631–1635)     

大鼠70%肝切除后不同程度门静脉狭窄门静脉流速比值

目的 观察大鼠70%肝切除后不同程度门静脉狭窄（PVS）模型门静脉血流速度（PVV）比值（PVVR）变化。方法 根据手术方法将102只大鼠随机分为对照组（n=6）、无PVS组及轻、中、重度PVS组（每组各24只）。对无PVS组大鼠仅行70%肝脏切除而不结扎门静脉,轻、中、重度PVS组则在部分肝脏切除基础上不同程度结扎门静脉。于术后1、3、7、14天超声检测PVV,PVS组测量并计算PVVR,结合术后3天核分裂指数（MI）和7天肝再生度（LRD）,分析各组PVVR变化。结果 无PVS组及中度PVS组MI高于轻度PVS组（P均<0.05）,重度PVS组MI明显低于中度PVS组;重度PVS组LRD明显低于无PVS组和中度PVS组（P均<0.05）。无PVS组术后3天PVV降至最小,7、14天回升。不同程度PVS组大鼠术后7天PVVR下降至最小,14天时有所回升,且术后1天和3天重度组明显大于轻、中度组（P均<0.05）,术后7天和14天各组间PVVR差异均无统计学意义（P均>0.05）。结论 超声可准确观察大鼠部分肝脏切除术后PVS血流改变;推测大鼠PVVR变化可能与肝细胞病理改变、核分裂状态、再生肝脏体积等因素有关。     

Segmental pulmonary vein ablation: success rates with and without exclusion of areas adjacent to the esophagus

Background: Catheter ablation has become the first line of therapy in patients with symptomatic recurrent, drug‐refractory atrial fibrillation (AF). The occurrence of an atrioesophageal fistula is a rare but serious complication after AF‐ablation procedures. This risk is even present during segmental pulmonary vein (PV) ablation procedures because the esophagus does frequently have a very close anatomical relationship to the right or left PV ostia. The aim of the present study was to analyze whether the exclusion of areas adjacent to the esophagus does have a significant effect on the success rates after segmental pulmonary vein ablation procedures. Methods: Forty‐three consecutive patients with symptomatic paroxysmal AF were enrolled in this study. In all patients, a segmental PV ablation procedure was performed. The procedures were facilitated by a 3D real‐time visualization of the circumferential mapping catheter placed in the pulmonary veins using the NavX? system (St. Jude Medical, St. Paul, MN, USA; open irrigated tip ablation catheter; 43°C; 30 W). In 21 patients, a complete ostial PV isolation was attempted regardless of the anatomical relationship between the ablation sites and the esophagus (group A). In the remaining 22 patients, the esophagus was marked by a stomach tube and areas adjacent to the esophagus were excluded from the ablation procedure (group B). After discharge, patients were scheduled for repeated visits at the arrhythmia clinic at 1, 3, and 6 months after the ablation procedure. Results: The segmental pulmonary vein ablation procedure could be performed as planned in all patients. In group A, all pulmonary veins could be isolated successfully in 14 out of 21 patients (67%). A mean number of 3.7 pulmonary veins (SD ± 0.5 PVs) were isolated per patient. The main reasons for an incomplete PV isolation were: small diameter of the PVs, side branches close to the ostium, or poorly accessible PV ostia. In group B, all PVs could be isolated successfully in only 12 out of 22 patients (55%; P = 0.54). A mean number of 3.2 PVs (SD ± 0.9 PVs) were isolated per patient (P = 0.05). This was mostly due to a close anatomical relationship to the esophagus. The ablation strategy had to be modified in 16/22 patients in group B because of a close anatomical relationship between the left (n = 10) or right (n = 6) PV ostia and the esophagus. After 3 months, the percentage of patients free from an AF recurrence was not significantly different between the two groups (90% vs 95%; P = 0.61). After 6 months, there was no significant difference between the success rates either (81% vs 82%; P = 1.0). There were no major complications in both groups. Conclusions: The exclusion of areas adjacent to the esophagus results in a moderately higher percentage of incompletely isolated PVs. However, it does not have a significant effect on the AF recurrence rate during short‐term and mid‐term follow‐up.     

Pulmonary vein imaging: comparison of 3D magnetic resonance angiography with 2D cine MRI for characterizing anatomy and size.

Pulmonary vein imaging is integral for planning atrial fibrillation ablation procedures. We tested the feasibility of quantifying pulmonary vein ostial diameter using two-dimensional cine cardiac magnetic resonance (2D cine CMR) and three-dimensional magnetic resonance angiography (3D MRA). Nine patients with a history of atrial fibrillation and 20 normal volunteers underwent 2D cine CMR and contrast-enhanced 3D MRA of pulmonary veins on a 1.5 T scanner. Pulmonary vein ostial diameters were measured and pulmonary vein vessel border sharpness was graded qualitatively. Both techniques provided excellent pulmonary vein imaging; however, 3D MRA was faster to perform. The average difference between the systolic and diastolic pulmonary vein diameter was 2.5 mm (23.2%, p < 0.0001) in normal volunteers and 2.2 mm (16.9%, p < 0.0001) in atrial fibrillation patients. The ostial diameter measurements by 3D MRA were significantly larger than on 2D cine CMR. Additionally, the pulmonary vein borders appeared sharper with 2D cine CMR compared to 3D MRA. In conclusion, the 2D images can resolve differences in diameter across the cardiac cycle, while the 3D images provide high quality anatomical depiction but blur borders due to pulsatile motion. We suggest a protocol combining 2D cine CMR and 3D MRA for comprehensive evaluation of pulmonary veins.     

Prognostic value of pulmonary vein size in prediction of atrial fibrillation recurrence after pulmonary vein isolation: a cardiovascular magnetic resonance study

Background

The relationship between pulmonary vein (PV) anatomy and successful catheter ablation of atrial fibrillation (AF) is poorly understood

Methods

First-pass contrast enhanced PV magnetic resonance angiography was performed in 71 consecutive patients prior to PV isolation. PV diameter and cross-sectional area (CSA) were measured prior to PV isolation. Any symptomatic or asymptomatic AF >10s was considered a recurrence. Early recurrence was defined as recurrent AF ≤30 days after PV isolation, while late recurrence of AF was defined as recurrent AF >30 days after.

Results

At 1 year, 57 % had any recurrence of AF while 41 % had late recurrence of AF. Study subjects with one or more PV diameter in the top 10^th percentile had trend toward more early recurrent AF (HR 1.99, p = 0.053). Study subjects with one or more PV CSA in the top 10^th percentile had more late recurrent AF (HR 2.25, p = 0.039) and a trend toward more early recurrent AF (HR 1.94, p = 0.064). With multivariate analysis, PV size was not associated with early recurrent AF, but late recurrent AF was associated with one or more large PV, increased left atrial size, and non-paroxysmal AF. Study subjects with all three of these risk factors had a 100 % rate of late recurrent AF at 1 year, while those with none had a 7 % rate of late recurrent AF.

Conclusions

Larger PV size is independently associated with more late recurrent AF after PV isolation. Determination of PV size prior to PV isolation may predict procedural success.     

A novel double cryoballoon strategy in persistent atrial fibrillation: a pilot study

Aims

Cryoballoon technology is a promising technique in paroxysmal atrial fibrillation (AF) ablation. However, success rates in patients with persistent AF have not been convincing. There is a trend toward performing more extensive procedures that are referred to as ‘pulmonary vein isolation plus.’ To combine pulmonary vein isolation (PVI) and antral substrate modification, we used both the 23-mm and 28-mm cryoballoon in a single approach in patients with persistent AF.

Methods and results

33 consecutive patients (26 men, age 60?±?10?years, LA size 44?±?5?mm) with persistent AF were prospectively included. All patients underwent the “double balloon strategy:” at least two applications at each pulmonary vein (PV) using the smaller 23-mm balloon to isolate the PV at the ostial level plus at least one additional freeze by the 28-mm balloon at the wide PV antral level. 7-day Holter monitors were performed during follow-up at 1, 3, 6, 9, 12, 18 and 24?months post-ablation. 131 of 133 PVs were targeted and isolated (98.4?%). A mean of 14?±?2 cryoballoon applications per patient or 3.5?±?1.5 applications per vein were performed. After a single procedure and mean follow-up of 15?±?3?months, 69.7?% of patients remained in sinus rhythm (3-month blanking period). There were no major complications.

Conclusions

In persistent AF, the “double balloon strategy;” combining the small and large cryoballoon allowed ostial PV isolation followed by antral cryoablation is feasible, safe and associated with a favorable outcome.     

大脑中动脉M1段闭塞后动脉偏侧优势与突出血管征的相关性

目的探讨单侧大脑中动脉M1段闭塞后,动脉偏侧优势与突出血管征（PVS）之间的相关性,并分析动脉偏侧优势及PVS与患者神经功能缺失程度之间的相关性。方法收集2018年1月~2020年3月单侧大脑中动脉M1段闭塞的急性缺血性脑卒中患者48例,其中男性27例,女性21例,年龄38~78岁（52.8±7.7岁）。依据三维时间飞跃法磁共振血管成像提示有无患侧大脑前动脉和（或）大脑后动脉偏侧优势分为偏侧优势组（n=26）和对照组（n=22）,观察两组患者T2*加权血管成像序列显示的PVS差异。依据T2*加权血管成像序列提示梗死灶周围有无PVS将入组患者分为PVS阳性组（n=27）和阴性组（n=21）,分别于患者入院当日及1周后将偏侧优势组和对照组、PVS阴性和PVS阳性组利用美国国立卫生研究院脑卒中评分量表（NIHSS）进行评分,并分析评分差异。结果48例患者中,偏侧优势组出现PVS为42.31%（11/26）,对照组患者出现PVS为72.73%（16/22）,对照组高于偏侧优势组（P＜0.05）;偏侧优势组及PVS阴性组患者入院当日及1周后NIHSS评分均低于对照组及PVS阳性组（P＜0.05）。结论单侧大脑中动脉M1段闭塞后,大脑动脉偏侧优势及PVS阴性提示侧支循环建立及良好的灌注状态,并与患者近期预后密切相关。     

Normal pulmonary veins anatomy is associated with better AF-free survival after cryoablation as compared to atypical anatomy with common left pulmonary vein

Background: Pulmonary vein cryoablation (PVC) is a new approach in the treatment of recurrent atrial fibrillation (AF). Computed tomography (CT) can be used to evaluate the left atrium anatomy and PVs dimensions to facilitate the procedure. In radiofrequency procedures, some anatomic variants such as common left (CLPV) or right (CRPV) PV were reported as factors associated with technical procedure difficulties and potential long‐term complications. We hypothesized that the absence of CLPV as determined by CT would predict better AF‐free survival after PVC. Methods and results: We included 118 consecutive patients (mean age 56 ± 10 years; 77% males) with drug refractory paroxysmal (72%)/persistent (28%) AF, with more than 6 months follow‐up, who underwent PVC. On CT scanning images performed within 1 month prior to ablation, we evaluated PV anatomic patterns: presence of CLPV or CRPV. Each patient was evaluated by 24‐hour Holter monitoring within 1 and 3 months and all patients were periodically evaluated at 1, 3, and 6 months, and every 6 months thereafter. Patients were asked to record their 12‐lead electrocardiogram whenever they experienced symptoms suggestive of AF. Recurrence was defined as AF that lasted at least 30 seconds. CLPV was present in 30 (25%) patients and no patients with CRPV were identified. At the end of the 13 months follow‐up, patients with normal PVs had significantly better AF‐free survival compared to patients with CLPV (67% vs 50%, P = 0.02). The difference was present in patients with paroxysmal AF (P = 0.008) but not in patients with persistent AF (P = 0.92). Conclusion: In patients undergoing cryoballoon PV isolation for AF, the presence of normal PVs pattern is associated with better AF‐free survival as compared to atypical PV anatomy with CLPV, particularly in patients with paroxysmal AF. (PACE 2011; 34:837–843)     

Dilatation of the pulmonary veins in atrial fibrillation: a transesophageal echocardiographic evaluation

Ectopic beats originating from sleeves of atrial tissue within the pulmonary veins (PVs) can induce and sustain paroxysmal atrial fibrillation (AF). Left atrial stretch and dilatation favors the development of atrial ectopy and AF. Similarly, PV dilatation, if present, might trigger PV ectopy in patients with AF. This study was designed to evaluate whether PV dilatation is present in patients with nonfocal AF and whether the PV diameter correlates to the left atrial diameter (LAD). The diameters of the right superior (RSPV) and left superior PV (LSPV) were measured at the ostium and at a depth of 1 cm in 170 patients (AF, n = 75; sinus rhythm [SR], n = 95) using transesophageal echocardiography. The LAD was determined by transthoracic echocardiography. The diameters of the PVs were significantly larger in patients with AF than in patients with SR (LSPV(ostium): AF 13.6 +/- 3.5 mm vs SR 10.6 +/- 2.7 mm, P < 0.001; LSVP(1cm): AF 12.5 +/- 2.9 mm vs SR 10.2 +/- 2.5 mm, P < 0.001; RSPV(ostium): AF 13.9 +/- 3.5 mm vs SR 11.7 +/- 2.9 mm, P < 0.001; RSVP(1cm): AF 12.8 +/- 2.8 mm vs SR 10.6 +/- 2.6 mm, P < 0.05). Similarly, LAD was larger in patients with AF (44.7 +/- 7.7 mm) as compared to patients with SR (38.8 +/- 6.8 mm, P < 0.001). Neither for the SR nor the AF group did the PV size correlate to the LAD. AF is associated with a significant enlargement of the RSPV, LSPV, and LAD. There is no correlation between LAD and PV diameters. This raises the question whether PV dilatation in patients with AF is a cause or a consequence of AF and whether it may contribute to the development and perpetuation of AF.     

Antiarrhythmic Drug Therapy after Radiofrequency Catheter Ablation in Patients with Atrial Fibrillation

Objectives: The use of antiarrhythmic drugs after ablation is a controversial issue when evaluating the efficacy of atrial fibrillation (AF) ablation. This study compares in a prospective and randomized fashion the impact of an antiarrhythmic drug in preventing AF recurrence after AF ablation.
Methods: From February 2004 to May 2005, 107 consecutive patients (mean age 57 ± 10 years, 69 men), with paroxysmal (60%) or persistent (40%) drug refractory AF, were randomly assigned to ablation alone (Group A, 53 patients) or combined with the best antiarrhythmic therapy, preferably amiodarone (Group B, 54 patients). All patients underwent cavo-tricuspid and left inferior pulmonary vein (PV)-mitral isthmus ablation plus circumferential PV ablation, using a guided electro-anatomical approach. Standard electrocardiograms (ECG), and ambulatory and transtelephonic ECG monitoring were used to assess AF recurrences. Recurrences during the first month after ablation were excluded from this analysis.
Results: At 12 months of follow-up, no significant difference was observed in the rates of AF recurrences between Group A (18/53 patients, 34%) and Group B (16/54 patients, 30%). The percentage of patients with ≥1 asymptomatic AF episode was higher in Group B than in Group A (10/16 patients, 63%, vs 5/18 patients, 28%, P = 0.04).
Conclusions: Continuing antiarrhythmic drug therapy in patients who undergo catheter ablation for AF did not lower the rate of AF recurrences. Antiarrhythmic drugs increased the proportion of patients with asymptomatic AF episodes.     

Is Isolation of All Four Pulmonary Veins Necessary in Patients with Paroxysmal Atrial Fibrillation?

The upper pulmonary veins (PVs) are responsible for the majority of atrial fibrillation (AF) triggering foci, whereas the inferior PVs are more difficult to ablate and prone to postablation ostial stenosis. Most procedure failures can be attributed to incomplete isolation or recurrent PV left atrial reconnection rather than to identification of another focus. Furthermore, in certain patients AF triggers can be detected outside the PVs, and local denervation of the ganglionic plexus around the superior PV left atrial junctions following the ablation procedure may also play a role in eliminating AF. Based on these data, the authors propose that in AF patients the superior PVs should be ablated first, and in case of recurrence a second procedure should be performed for identification of PV left atrial reconnection or extrapulmonary foci and additional ablation of the inferior PVs. Such a staged approach might offer slightly lower success rates but with a significantly lower radiation exposure and procedural time and at a smaller risk of ablation induced PV stenosis.     

Protracted CRP elevation after atrial fibrillation ablation

Background: Atrial fibrillation (AF) has been linked to an inflammatory process detected through various biomarkers, including C-Reactive Protein (CRP). Early recurrence of AF within the first 3 months after curative AF ablation is not felt to reflect success or failure of the procedure. We hypothesized that this early recurrence is due to an inflammatory response to the ablation itself. We therefore sought to evaluate levels of CRP after AF ablation.
Methods: We prospectively enrolled subjects undergoing AF ablation. A control group of patients undergoing ablation for supraventricular tachycardia (SVT) was also enrolled. Each patient had CRP drawn on the day of the procedure (prior to ablation) and during their first follow-up (median 49 days, interquartile range [IQR] 37–93) and second follow-up (median 147 days, IQR 141–257) clinic visits. Patient interviews were performed and medical histories reviewed for evidence of recurrent AF prior to the first follow-up.
Results: CRP levels significantly increased from baseline to first follow-up in the AF ablation group (P = 0.0017). CRP did not significantly change after SVT ablation (P = 0.92). Seventeen (45%) of the AF subjects exhibited recurrence of AF prior to first follow-up. After adjusting for multiple potential confounders, AF ablation patients with recurrent AF prior to their first follow-up had a statistically significant greater odds of having an increase in CRP (OR 21, 95% CI 1.1–417, P = 0.045).
Conclusions: AF ablation generates an inflammatory response that persists for several weeks. This inflammation may explain early recurrence of AF after curative ablation.     

Pulmonary vein stenosis and remodeling after electrical isolation for treatment of atrial fibrillation: short- and medium-term follow-up

Asymptomatic pulmonary vein (PV) stenosis after PV electrical isolation for atrial fibrillation has been reported in several studies and may be due to dynamic factors. The purpose of this study was to determine if PV stenosis progresses after the initial procedure. Consecutive patients (n = 26) requiring repeat procedures for atrial fibrillation recurrence were studied (mean age 55 +/- 12 years). Segmental PV potential-guided ostial ablation was performed with transvenous catheters. Biplane angiographic images were obtained before and after each procedure (52 procedures). Stenoses were found in 14 (16%) of 87 targeted veins immediately after the initial procedures. After 129 +/- 94 days no new stenoses were found at the second procedure. PV stenoses were unchanged in 8 previously stenosed veins, slightly deteriorated in 1 vein, improved in 2 veins, and fully resolved in 3 veins. No patients had symptoms attributable to PV stenosis. PV stenosis occurred in 6 (9%) of 68 additional veins at the second procedure. No baseline or procedural characteristics predicted stenosis. Progression of PV stenosis is uncommon in the medium term. Complete or partial resolution of PV stenosis occurs in approximately one third of cases. Absence of PV stenosis after an initial procedure does not ensure PV stenosis will not occur with further ablation in the same vein.