Intracardiac ultrasound-guided transseptal puncture in horses: Outcome, follow-up, and perioperative anticoagulant treatment

BACKGROUND

Cardiac catheterizations in horses are mainly performed in the right heart, as access to the left heart traditionally requires an arterial approach. Transseptal puncture (TSP) has been adapted for horses but data on follow-up and closure of the iatrogenic atrial septal defect (iASD) are lacking.

HYPOTHESIS/OBJECTIVES

To perform TSP and assess postoperative complications and iASD closure over a minimum of 4 weeks.

ANIMALS

Eleven healthy adult horses.

METHODS

Transseptal puncture was performed under general anesthesia. Serum cardiac troponin I concentrations were measured before and after puncture. Weekly, iASD closure was monitored using transthoracic and intracardiac echocardiography. Relationship between activated clotting time and anti-factor Xa activity during postoperative enoxaparin treatment was assessed in vitro and in vivo.

RESULTS

Transseptal puncture was successfully achieved in all horses within a median duration of 22 (range, 10-104) minutes. Balloon dilatation of the puncture site for sheath advancement was needed in 4 horses. Atrial arrhythmias occurred in 9/11 horses, including atrial premature depolarizations (N = 1), atrial tachycardia (N = 5), and fibrillation (N = 3). Serum cardiac troponin I concentrations increased after TSP, but remained under the reference value in 10/11 horses. Median time to iASD closure was 14 (1-35) days. Activated clotting time correlated with anti-factor Xa activity in vitro but not in vivo.

CONCLUSIONS AND CLINICAL IMPORTANCE

Transseptal puncture was successfully performed in all horses. The technique was safe and spontaneous iASD closure occurred in all horses. Clinical application of TSP will allow characterization and treatment of left-sided arrhythmias in horses.

Incidence and predictors of persistent iatrogenic atrial septal defect following catheter ablation

BACKGROUND

The left atrium approach for atrial fibrillation (AF) ablation requires an atrial transseptal puncture that may cause an iatrogenic atrial septal defect (iASD). This study aimed to investigate the incidence and predictors of iASD in catheter ablation, assessed by transthoracic echocardiography (TTE), a relatively non-invasive technique frequently employed in follow-up.

METHODS

This retrospective study included 639 patients (489 male; 60.2±10.7years) who underwent initial catheter ablation for AF between May 2005 and June 2018. All patients underwent preprocedural transesophageal echocardiography (pre-TEE), preprocedural TTE (pre-TTE), and TTE one day after the procedure (post-TTE). iASD incidence after 6months (6M), preprocedural characteristics, and procedure methods were evaluated.

RESULTS

Patent foramen ovale (PFO) was diagnosed in 42 patients (6.6%) using pre-TEE and in 11 patients using pre-TTE (26.2% of the patients with PFO in pre-TEE). Among the 597 patients without PFO, 497 underwent 6M-TTE. iASD was observed in 59.6% of patients using post-TTE and 4.6% using 6M-TTE. In the univariate logistic regression analysis, the total diameter of the sheath through the septum (odds ratio 1.15, p<0.001) or two sheaths through a single puncture (odds ratio 4.17, p=0.001) were independent risk factors on iASD incidence in 6M-TTE. iASD was also more likely to occur via cryoballoon ablation using a larger sheath than radiofrequency catheter ablation.

CONCLUSIONS

iASD was not a rare complication. A larger sheath diameter or two sheaths through a single puncture were associated with the incidence of iASD.

Intracardiac echocardiographic imaging with a cartosound module for guidance of left atrial appendage closure: a comparative study with transesophageal echocardiographic imaging

PURPOSE

In most clinical trials, intracardiac echocardiography (ICE) has provided fewer views than the four standard views provided by transesophageal echocardiography (TEE) when assessing left atrial appendage closure (LAAC) devices. This study aimed to determine if ICE guided by the CartoSound system achieve adequate high-quality views and similar clinical outcomes as TEE during LAAC.

METHODS

This study prospectively enrolled 202 patients who underwent LAAC using either ICE (n = 69), TEE (n = 121), or a combination of ICE and TEE (n = 12) as the procedural imaging under local anesthesia. A novel multi-angled "FLAVOR" approach was used for assessment in the ICE group.

RESULTS

ICE allowed visualization of the implanted devices in all patients at all proposed angles with long-axis views while two-dimensional (2D) TEE showed short-axis views in 1 or 2 angles in 24.2% of cases, which was more prevalent when the pulmonary ridge was covered by the occluder. In the combined ICE-TEE cohort, 2D-TEE failed to detect peri-device leak in 1 patient. The complication rates were similar between the ICE and TEE groups. Shorter fluoroscopy time, lower radiation dose and contrast usage were founded in the ICE group. At first TEE follow-up, the rate and degree of peri-device leak were similar between the ICE and TEE groups.

CONCLUSION

A systematic ICE protocol using a CartoSound module to guide LAAC was reliable for comprehensive long-axis imaging assessment compared with 2D/3D TEE under local anesthesia with a shorter fluoroscopy time, lower radiation dose, and less use of contrast.

Outcome and safety of intracardiac echocardiography guided left atrial appendage closure within zero-fluoroscopy atrial fibrillation ablation procedures

BACKGROUND

Simultaneous atrial fibrillation (AF) catheter ablation and left atrial appendage closure (LAAC) is sometimes recommended for both rhythm control and stroke prevention. However, the advantages of intracardiac echocardiography (ICE) guidance for this combined procedure have been scarcely reported. We aim to evaluate the clinical outcomes and safety of ICE guided LAAC within a zero-fluoroscopy catheter ablation procedure.

METHODS AND RESULTS

From April 2019 to April 2020, 56 patients with symptomatic AF underwent concomitant catheter ablation and LAAC. ICE with a multi-angled imaging protocol mimicking the TEE echo windows was used to guide LAAC. Successful radiofrequency catheter ablation and LAAC were achieved in all patients. Procedure related adverse event rate was 3.6%. During the 12-month follow-up, 75.0% of patients became free of arrhythmia recurrences and oral anticoagulants were discontinued in 96.4% of patients. No ischemic stroke occurred despite two cases of device-related thrombosis versus an expected stroke rate of 4.8% based on the CHA₂ DS₂ -VASc score. The overall major bleeding events rate was 1.8%, which represented a relative reduction of 68% versus an expected bleeding rate of 5.7% based on the HAS-BLED score of the patient cohort. The incidence of iatrogenic atrial septal defect secondary to a single transseptal access dropped from 57.9% at 2 months to 4.2% at 12 months TEE follow-up.

CONCLUSION

The combination of catheter ablation and LAAC under ICE guidance was safe and effective in AF patients with high stroke risk. ICE with our novel protocol was technically feasible for comprehensive and systematic assessment of device implantation. This article is protected by copyright. All rights reserved.

Incidence, persistence, and clinical relevance of iatrogenic atrial septal defects after percutaneous left atrial appendage occlusion

OBJECTIVE

To investigate the rate and clinical impact of a persisting iatrogenic atrial septal defect (iASD) after percutaneous left atrial appendage occlusion (LAAO).

BACKGROUND

Percutaneous LAAO is an alternative to oral anticoagulation (OAC) for the prevention of ischemic stroke and systemic embolism in patients with atrial fibrillation (AF). Data regarding incidence and persistence of iASD after LAAO procedures and its clinical relevance is scarce.

METHODS

We retrospectively analyzed 144 patients that underwent LAAO at our center between 2009 and 2020 who had at least one follow-up including transesophageal echocardiography (TEE). Baseline clinical, procedural data and echocardiographic characteristics in patients with and without evidence of an iASD were compared. We furthermore determined the rate of iASD persistence over time and evaluated outcomes of patients with and without spontaneous iASD closure.

RESULTS

After a median of 92 days (IQR 75-108 days) after LAAO, 50 patients (50/144, 34.7%) showed evidence of an iASD. Patients with iASD had higher CHADS-VASc-scores (4.9±1.5 vs 4.2±1.2, p = 0.03), larger left atrial volumes (80.5±30.5 ml vs 67.1±19.7 ml, p = 0.01) and were more likely to have relevant mitral regurgitation (≥° II) (46.0% vs 12.3%, p = 0.001). LAAO procedures took longer (50.1±24.3 vs 41.1±17.8 min, p = 0.06) in patients with a persisting iASD. Furthermore, larger device sizes were implanted (24.3±3.4 mm vs 22.1±2.8 mm, p = 0.03). The presence of an iASD had no impact on RV dysfunction, thromboembolism or mortality. Spontaneous closure of an iASD was documented in 52.0% (26/50). Hereby, similar risk factors were identified for the persistence of an iASD in follow-up.

A modified percutaneous atrial balloon septoplasty for difficult transseptal puncture

Catheter ablation of atrial fibrillation sometimes encounters difficulty in passing the interatrial septum. This study reports a modified percutaneous atrial balloon septoplasty with short balloon to gain access to left atrium (LA) during challenging transseptal puncture (TSP).We retrospectively analyzed 20 patients (61.75 ± 7.31 years, 45% male) who received modified percutaneous atrial balloon septoplasty from August 2015 to October 2018. Soft-headed balance middle weight (BMW) guidewire was inserted into left superior pulmonary vein (LSPV) and short non-compliant balloon (15 mm in length and 4.0 or 5.0 mm in diameter) was used for atrial balloon septoplasty (ABS). Interatrial septum was located with inflated balloon and contrast "Hitting Wall" sign. All patients were followed-up for iatrogenic atrial septal defect (iASD) and other related complications.ABS and LA access were performed successfully without complications in all 20 patients. Time needed for ABS was correlated to the number of prior TSP (P = .007). During the 6-month follow-up, no remaining iASD was found by echocardiography.For atrial fibrillation patients with difficulty in passing the interatrial septum, this modified percutaneous ABS might be an alternative strategy which is safe to obtain transseptal access without short or long term complications.

Management of Iatrogenic Atrial Septal Defects in the Era of Large-Bore Transcatheter Mitral Valve Therapies

Several case reports described acute and subacute decompensations that were reversed after percutaneous interatrial septal defect (ASD) closure. At least 30% of patients post MitraClip will continue to have a persistent ASD at 1 year. Few retrospective studies described various echocardiographic associations with persistent ASD but there is no conclusive evidence that it is the cause of a poor outcome. Conclusion: At this time routine closure of ASD post MitraClip is not recommended unless there is hemodynamic decompensation that cannot be explained by other factors.

A novel and easy approach to difficult transseptal puncture during atrial fibrillation ablation

AIMS

Transseptal passage is sometimes difficult to obtain. This study evaluates the feasibility and safety of a novel and easy transseptal puncture (TSP) technique named 2D2G (using two dilators and two guidewires) in patients with difficult TSP.

METHODS AND RESULTS

Forty-four paroxysmal atrial fibrillation patients with difficult TSP were enrolled in this study. They were allocated to the 2D2G group or the conventional group in a 1:1 fashion. The primary endpoint in both groups was successful TSP without changing the puncture site or using auxiliary tools. The secondary endpoints were the safety, total transseptal puncture time, and ablation time. There were no differences in baseline demographic or clinical characteristics between the two groups. Successful LA access in the 2D2G group was 100% (vs. 64%, P < 0.05). The total TSP time (10 ± 3 min vs. 5 ± 1 min, P < 0.05) and ablation time (42 ± 19 min vs. 58 ± 22 min, P < 0.05) in the conventional group were significantly longer than those in the 2D2G group. No major complications occurred in either group, and all the patients underwent successful circumferential pulmonary vein isolation (CPVI).

CONCLUSION

In AF patients with difficult TSP, the 2D2G technique is safe, feasible, and time-saving.

Impact of single versus double transseptal puncture on outcome and complications in pulmonary vein isolation procedures

BACKGROUND

The aim of the current study was to analyze the impact of single versus double transseptal puncture (TSP) for atrial fibrillation (AF) ablation.

METHODS

Consecutive patients undergoing AF ablation were prospectively included in the AF ablation registry and were analyzed according to single versus double TSP.

RESULTS

A total of 478 patients (female 35%, persistent AF 67%) undergoing AF ablation between 01/2014 and 09/2014 were included. Single TSP was performed in 202 (42%) patients, double TSP in 276 (58%) patients. Age, gender, body mass index, CHA2DS2-VASc score, left ventricular ejection fraction and operator experience (experienced operator defined as ≥ 5 years of experience in invasive electrophysiology) were equally distributed between the two groups. Repeat procedures (re-dos) were more frequently performed using single TSP access (p < 0.001). Left atrial (LA) diameter was larger in patients with double TSP (p = 0.001). Procedure duration in single TSP was identical to double TSP procedures (p = 0.823). Radiation duration was similar between the two groups (p = 0.217). There were 49 (10%) patients with complications after catheter ablation. There were no differences between complication rates and TSP type (p = 0.555). Similarly, recurrence rates were comparable between both TSP groups (p = 0.788).

CONCLUSIONS

There was no clear benefit of single or double TSP in AF ablation.

Thromboembolic Events Following Atrial Fibrillation Cardioversion and Ablation: What's the Culprit?

Stroke is a rare but possible complication after atrial fibrillation (AF) ablation. However, its etiopathogenesis is far from being completely characterized. Here we report a case of stroke, with recurrent peripheral embolism after AF ablation procedure. In our patient, an in situ femoral vein thrombosis and iatrogenic atrial septal defect were simultaneously detected. A comprehensive review of multiple pathophysiological mechanisms of stroke in this context is provided. The case underlines the importance of a global evaluation of patients undergoing AF ablation.

Migraine-like Headache after Transseptal Puncture for Catheter Ablation: A Case Report and Review of the Literature

Catheter ablation for atrial fibrillation creates an iatrogenic atrial septal defect by transseptal puncture, which may produce a transient right-to-left shunt. We encountered a 44-year-old man who presented with de novo migraine-like headache after cryoballoon ablation for atrial fibrillation. On reviewing the literature, we found additional cases in which migraine-like headache occurred within one week after the procedure and spontaneously within three months. We should recognize migraine-like headache as a potential complication of catheter ablation.

Percutaneous Closure of Persistent Atrial Septal Defects After Pulmonary Vein Isolation

Pulmonary vein isolation (PVI) with radiofrequency or cryoballoon ablation to treat atrial fibrillation requires trans-septal puncture. This creates a small iatrogenic atrial septal defect (iASD). In most patients, the defect spontaneously closes after 3-6 months. However, persistent iASDs can cause hemodynamic changes and adverse consequences from inter-atrial shunting. Persistent post PVI iASDs that are clinically significant can be closed percutaneously. This diagnosis should be considered in patients with worsening dyspnea or fatigue after PVI. We present a case of post PVI iASDs causing immediate or late onset hemodynamic changes and clinical symptoms, which improved after ASD closure. We provide a review of previously reported cases and literature on post PVI ASD prevalence, risk factors and outcomes after ASD closure.

Recognizing and reacting to complications of trans-septal puncture

INTRODUCTION

The transseptal puncture (TSP) enables access to the left heart, through the fossa ovalis (FO), both in electrophysiology and in cardiac interventional procedures. TSP is usually safe in experienced hands. Sometimes TSP can be technically demanding and carries the risk of severe complications in approximately 1%. While performing a TSP, every effort should be taken in order to avoid complications. In the event of complications, prompt recognition and reaction are essential and a combined 'heart-team' management may be the most effective approach. Areas covered: Main TSP-related complications are cardiac tamponade, aortic root puncture, embolic stroke, transient ST elevation of inferior leads and iatrogenic atrial septal defect. A challenging TSP may be expected in presence of difficult IAS-FO anatomies, previous TSP, IAS occluder device and previous IAS surgical repair. Use of echo imaging and special needles (ie., radiofrequency needle and J-shaped guidewire) may avoid TSP-related complications in difficult settings. Expert commentary: Some tools are available to help minimize the risks of TSP. However, their availability might be limited. To increase safety of TSP, an adequate training of physicians, identification of patients in whom it might be difficult and a prompt recognition of complications seem to be the most important background.

Transseptal puncture - Review of anatomy, techniques, complications and challenges

In recent years, the transseptal puncture approach has enabled passage of increasingly large and complex devices into the left atrium. Traditional tools remain effective in creating and dilating the initial puncture, with an acceptable safety profile. Even for skilled operators, the procedure is technically demanding and requires sound understanding of atrial anatomy. Intracardiac echocardiography is useful in cases of previous septal repair, poorly defined fossa ovalis anatomy or when considering patent foramen ovale portal crossing. Iatrogenic atrial septal defect (iASD) is the most commonly encountered long-term complication and there is increasing evidence that larger devices are leading to symptomatic defects. The size of the sheath crossing the septum is the strongest predictor of iASD formation but other factors such as longer procedure times, significant catheter manipulation and high pulmonary pressures also contribute. Transcatheter mitral valve repair involves the use of large 22 Fr catheters which carry alarmingly high rates of defect persistence with precipitation of symptoms and possible influence on mortality. Long-term follow up data, particularly beyond the 12-month period are lacking and resultantly, evidence to guide management is sparse. Refinements of conventional instruments, as well as innovations to puncture the septum without mechanical pressure, herald a progressively safer future for the transseptal technique.

Ischemic Stroke or Systemic Embolism After Transseptal Ablation of Arrhythmias in Patients With Cardiac Implantable Electronic Devices

Background

Incidental mobile thrombi are commonly found on endovascular leads of cardiac implantable electronic devices (CIEDs). Transseptal puncture for catheter ablation of arrhythmia poses a risk for paradoxical embolism. We examined risk of ischemic stroke, transient ischemic attack (TIA), or systemic embolism after transseptal ablation in patients with and without CIEDs.

Methods and Results

Using a national administrative claims database, 31 720 patients who underwent a transseptal catheter ablation between January 2004 and September 2014 were identified. Two propensity‐matched cohorts were created by matching demographic variables, administrative variables, Charlson Comorbidity Index, CHA₂DS₂‐Vasc score, and year and indication for ablation (5533 and 11 300 patients with and without CIEDs). Incidence rates and Cox proportional hazards models were used to estimate risk of ischemic stroke, TIA, or systemic embolism for patients with and without CIEDs. Impact of oral anticoagulation (OAC) use on the endpoint was examined. Over a mean follow‐up of 2.1 years, the incidence of the combined endpoint was 1.9 per 100 person‐years in patients with CIEDs and 1.5 per 100 person‐years in patients without CIEDs (P=0.03). Among patients not on OAC, presence of a cardiac device was associated with an increased risk (hazard ratio [HR], 1.71 [1.24–2.35]; P<0.01), whereas there was no association noted among patients treated with OAC (HR, 0.98 [0.75–1.28]).

Conclusion

CIEDs are associated with an increased risk of stroke, TIA, or systemic embolism after transseptal ablation, but this risk is attenuated with postablation OAC use. Role of anticoagulation post‐transseptal ablation in patients with CIED warrants further investigation.

Experience matters: long-term results of pulmonary vein isolation using a robotic navigation system for the treatment of paroxysmal atrial fibrillation

BACKGROUND

Long-term results after circumferential pulmonary vein isolation (CPVI) for the treatment of paroxysmal atrial fibrillation (PAF) using a robotic navigation system (RNS) have not yet been reported.

OBJECTIVE

To evaluate long-term results of patients with PAF after CPVI using RNS.

METHODS

In this study, 200 patients (n = 151 (75.5%) male; median age 62.2 (54.7-67.7) years) with PAF were evaluated. In 100 patients, RNS (RN-group) was used for CPVI and compared to 100 manually ablated control patients (MN-group). Radiofrequency was used in conjunction with 3D electroanatomic mapping. Power was limited to 30 watts (W) at the posterior left atrial (LA) wall in the first 49 RNS patients (RN-group-a). After esophageal perforation occurred in one RN-group-a patient, maximum power was reduced to 20 W for the subsequent 51 patients (RN-group-b).

RESULTS

After a median follow-up of 2 years, single (77/100 vs 77/100, p = 0.89) and multiple (90/100 vs 93/100, p = 0.29) procedure success rates were comparable between RN-group and MN-group. Single procedure success rate was significantly lower in RN-group-a as compared to RN-group-b (65.3 vs 88.2%, p = 0.047). In RN-group-a patients, procedural times [200 (170-230) vs 152 (132-200) minutes, p < 0.01] and fluoroscopy times [16.6 (12.9-21.6) minutes vs 13.7 (9.5-19) minutes, p = 0.043] were significantly longer compared to RN-group-b patients.

CONCLUSION

Long-term success rate after CPVI using RNS was comparable to manual ablation. Despite a lower power limit of 20 W at the posterior LA wall, single procedure success rate was higher in RN-group-b as compared to RN-group-a. Procedure time and fluoroscopy time decreased, whilst success rate increased with increasing experience in the RN-group.

Robotic ablation of atrial fibrillation

Background: Pulmonary vein isolation (PVI) is an established treatment for atrial fibrillation (AF). During PVI an electrical conduction block between pulmonary vein (PV) and left atrium (LA) is created. This conduction block prevents AF, which is triggered by irregular electric activity originating from the PV. However, transmural atrial lesions are required which can be challenging. Re-conduction and AF recurrence occur in 20 - 40% of the cases. Robotic catheter systems aim to improve catheter steerability. Here, a procedure with a new remote catheter system (RCS), is presented. Objective of this article is to show feasibility of robotic AF ablation with a novel system. Materials and Methods: After interatrial trans-septal puncture is performed using a long sheath and needle under fluoroscopic guidance. The needle is removed and a guide wire is placed in the left superior PV. Then an ablation catheter is positioned in the LA, using the sheath and wire as guide to the LA. LA angiography is performed over the sheath. A circular mapping catheter is positioned via the long sheath into the LA and a three-dimensional (3-D) anatomical reconstruction of the LA is performed. The handle of the ablation catheter is positioned in the robotic arm of the Amigo system and the ablation procedure begins. During the ablation procedure, the operator manipulates the ablation catheter via the robotic arm with the use of a remote control. The ablation is performed by creating point-by-point lesions around the left and right PV ostia. Contact force is measured at the catheter tip to provide feedback of catheter-tissue contact. Conduction block is confirmed by recording the PV potentials on the circular mapping catheter and by pacing maneuvers. The operator stays out of the radiationfield during ablation. Conclusion: The novel catheter system allows ablation with high stability on low operator fluoroscopy exposure.

Comparing Antiarrhythmic Drugs and Catheter Ablation for Treatment of Atrial Fibrillation

In the past years, catheter ablation has evolved into an effective treatment option for symptomatic, drug-resistant atrial fibrillation (AF) and it has recently been implemented as a primary treatment strategy for patients with paroxysmal AF. Although a significant number of studies have evaluated the potential benefits of catheter ablation compared with anti-arrhythmic drug (AAD)-therapy, to date, there are only a small number of randomised controlled trials in the literature, and several issues remain unsolved. The aim of this review is to analyze the current literature regarding this important issue and further discuss the question, whether catheter ablation may be more beneficial when compared to AAD therapy.

Echocardiographic evaluation of iatrogenic atrial septal defect after catheter-based mitral valve clip insertion

The geometries and sizes of persistent iatrogenic atrial septal defects (IASDs) after transseptal puncture during catheter-based mitral valve clip insertion (MVCI) have not been detailed. In this study, 11 IASDs were investigated in 10 patients who underwent MVCI using a guide catheter (24Fr proximally and 22Fr at the atrial septum). The diameters of the long and short axes and the area at maximum and minimum during a cardiac cycle were measured after MVCI using real-time 3-dimensional (RT3D) transesophageal echocardiography (TEE). A circular shape was assumed on 2-dimensional TEE, resulting in an area calculation of π × (dimension/2)(2). The anatomic geometries of IASDs were visualized in a 3-dimensional en face view of the atrial septum. Furthermore, 1 month after MVCI, IASDs were evaluated using echocardiography. The IASDs had a variety of irregular geometries. The mean long-axis diameter was 1.0 ± 0.24 cm, the mean short-axis diameter was 0.51 ± 0.22 cm, and the mean area was 0.40 ± 0.24 cm(2) on RT3D TEE. The diameters and area changed significantly between the maximal and minimal values during the cardiac cycle. Importantly, 2-dimensional TEE underestimated the maximal diameters of IASDs (0.54 ± 0.17 vs 1.0 ± 0.24 cm by RT3D TEE, p <0.01) and the maximal areas of IASDs (0.25 ± 0.15 vs 0.40 ± 0.23 cm(2) by RT3D TEE, p <0.05). One month after MVCI, the smallest and the second smallest IASDs had closed, and the other 9 remained open. In conclusion, RT3D TEE is useful to assess the irregular geometries of IASDs created during MVCI.

Incidence and long-term follow-up of silent cerebral lesions after pulmonary vein isolation using a remote robotic navigation system as compared with manual ablation

BACKGROUND

The incidence of silent cerebral lesions (SCL) after atrial fibrillation (AF) ablation is highly variable, depending on the technology used. Recently, an increased risk for SCL has been described for a novel, nonirrigated ablation tool using multielectrode phased radiofrequency (PVAC). The aim of this prospective study was to evaluate the incidence and long-term follow-up of SCL in patients undergoing robotically assisted pulmonary vein isolation (RA-PVI) as compared with manual PVI.

METHODS AND RESULTS

Circumferential PVI using irrigated radiofrequency current was performed on 70 patients (41 patients with paroxysmal AF, 59%). Fifty patients underwent RA-PVI and 20 patients underwent a manual approach. Cerebral MRI was performed the day before and the day after the ablation procedure; follow-up MRI was performed on 9 of 12 (75%) patients after a follow-up period of 21 months. SCLs were found in 12 of 70 (17%) patients in this study; the incidence of SCLs was similar in patients undergoing RA-PVI as compared with manually ablated patients (n=9, 18% versus n=3, 15%; probability value=1.0). In 1 patient undergoing manual PVI (1%), an SCL with asymptomatic subarachnoid hemorrhage was detected; the bleeding completely resolved within 1 month. Transient ischemic attack occurred in 1 (1%) patient 2 days after manual PVI. After a median follow-up period of 21 months, no residual SCLs were detected.

CONCLUSIONS

The incidence of SCL using the robotic navigation system was 18% in this study. Incidence and size of SCL appears to be similar after RA-PVI as compared with manual PVI. Repeat MRI showed no residual SCLs at long-term follow-up.

Left Atrial Catheter Ablation and Ischemic Stroke

Left atrial catheter ablation (LACA) has become an established therapy to abolish drug-refractory symptomatic paroxysmal and persistent atrial fibrillation. Restoring sinus rhythm by LACA may help to prevent atrial fibrillation-related strokes, but presently there is no evidence from randomized clinical trials to support this notion. This review summarizes the current knowledge and uncertainties regarding LACA and procedure-related ischemic stroke. In fact, most patients who undergo LACA have a rather low annual stroke risk even when left untreated, whereas LACA imposes a risk of procedure-related stroke of ≈0.5% to 1%. In addition, LACA may cause cerebral microemboli, resulting in ischemic lesions. These cerebral lesions, detectable by high-resolution MRI, could contribute to neuropsychological deficits and cognitive dysfunction. Furthermore, recurrent atrial fibrillaton episodes can be detected up to years after LACA and might cause ischemic strokes, especially in those patients in whom therapeutic anticoagulation was discontinued. Further prospective multicenter trials are needed to identify procedure-dependent risk factors for stroke and to optimize postprocedural anticoagulation management.

Usefulness of electroanatomical mapping during transseptal endocardial left ventricular lead implantation

AIM

Failure rate to implant left ventricular (LV) lead transvenously is 4-8% in cardiac resynchronization therapy (CRT) patients. Epicardial lead placement is an alternative method and if not applicable case reports and small series showed the feasibility of endocardial LV lead implantation. Electroanatomical mapping might be a useful tool to guide this procedure.

METHODS AND RESULTS

Four patients had undergone endocardial LV lead implantation after unsuccessful transvenous implantation or epicardial LV lead dysfunction using the transseptal approach. Electroanatomical mapping was used to mark the location of the transseptal puncture. This location point guided the mapping catheter from the subclavian access and facilitated positioning of the LV lead at the adjacent latest activation area of the left ventricle detected by activation mapping. Endocardial active fixation LV leads were successfully implanted in all patients with stable electrical parameters immediately after implantation and over a mean follow-up of 18.3 months (lead impedance 520 ± 177 vs. 439 ± 119 Ω and pacing threshold 0.8 ± 0.2 V, 0.5 ms vs. 0.6 ± 0.1 V, 0.5 ms, respectively). Patients were maintained on anticoagulation therapy with a target international normalized ratio of 3.5-4.5 and did not show any thromboembolic, haemorrhagic events, or infection. Echocardiography showed significant improvement of LV systolic function with marked improvement of the functional status.

CONCLUSIONS

Electroanatomical mapping is a useful technical tool to guide endocardial LV lead implantation. It helps to identify the location of the transseptal puncture and the use of activation mapping might facilitate location of the optimal lead positions during CRT.

Transseptal access and atrial fibrillation ablation guided by intracardiac echocardiography in patients with atrial septal closure devices

BACKGROUND

Percutaneous positioning of closure devices is a well-established treatment of atrial septal defects (ASDs). However, patients who have undergone the procedure are at increased risk for developing atrial fibrillation (AF), and treatment by catheter ablation is underutilized due to the perceived difficulty of obtaining transseptal access in the presence of the closure device.

OBJECTIVE

The purpose of this study was to report the acute and long-term results of radiofrequency catheter ablation of AF in patients with ASD closure devices.

METHODS

Thirty-nine patients (age 54 ± 6 years, 72% males) with drug-refractory AF (33% paroxysmal, 51% persistent, 16% long-standing persistent) and ASD closure devices (82% Amplatzer, 18% CardioSEAL) underwent radiofrequency catheter ablation. A double transseptal access guided by intracardiac echocardiography was obtained in all patients.

RESULTS

In 35 of 39 patients (90%), the transseptal access was obtained in a portion of the native septum, whereas in 4 of 39 patients (10%), a direct access through the device was required. The latter group had a significantly longer time for achieving the double transseptal access (73.6 ± 1.1 minutes vs. 4.3 ± 0.4 minutes, P < .001), longer fluoroscopy time (122 ± 5 minutes vs. 80 ± 8 minutes, P < .001), and total procedural time (4.1 ± 0.2 hours vs. 3.1 ± 0.3 hours, P < .001). At follow-up of 14 ± 4, months the overall success rate was 77% (85% in paroxysmal AF, 73% in nonparoxysmal AF). Transthoracic contrast-enhanced echocardiography with the Valsalva maneuver, performed between 3 and 6 months after the procedure, failed to detect shunt in all patients.

CONCLUSION

Radiofrequency catheter ablation of AF is feasible, safe, and effective in patients with ASD closure devices. Transseptal access can be obtained in portions of the native septum in the majority of cases. Direct transseptal puncture of the device is feasible and safe but requires longer time for each transseptal access.

The incidence and long-term clinical outcome of iatrogenic atrial septal defects secondary to transseptal catheterization with a 12F transseptal sheath

BACKGROUND

Studies assessing the presence of a residual iatrogenic atrial septal defect (iASD) after transseptal catheterization with 8F transseptal sheaths have suggested that the majority of these iASDs close within 6 months. However, these studies have been limited by small patient numbers and short follow-up. Additionally, there are a number of novel catheter procedures in interventional cardiology and electrophysiology that use larger transseptal sheaths. The objective of this study was to assess the incidence of and complications associated with iASDs in a large cohort of patients undergoing transseptal catheterization with a 12F transseptal sheath.

METHODS AND RESULTS

Patients (n=253) without a preexisting interatrial shunt undergoing WATCHMAN implantation as part of the PROTECT AF study were included in this current study. Patients underwent transesophageal echocardiography with echo-contrast immediately after the procedure and at 45 days and 6 months and 12 months. Eighty-seven percent of patients had an iASD immediately after the procedure, the majority of which sealed by 6 months (incidence of iASD, 34% at 45 days, 11% at 6 months, 7% at 12 months). Whereas the majority of iASDs were >3 mm in diameter immediately after the procedure, the minority of iASD were >3 mm during the follow-up period. Additionally, interatrial shunting was predominantly left-to-right when an iASD was present. There was no significant difference in the rate of stroke and/or systemic embolism during the follow-up period in patients with or without iASD.

CONCLUSIONS

Transseptal catheterization procedures with a large-diameter transseptal sheath have a high spontaneous closure rate of iASDs that is not associated with an increased rate of stroke/systemic embolization during long-term follow-up.