Patient Selection, Techniques, and Complication Mitigation for Epicardial Ventricular Tachycardia Ablation

Percutaneous epicardial ventricular tachycardia ablation can decrease implanted cardioverter defibrillator shocks and hospitalizations; proper patient selection and procedural technique are imperative to maximize the benefit-risk ratio. The best candidates for epicardial ventricular tachycardia will depend on history of prior ablation, type of cardiomyopathy, and specific electrocardiogram and cardiac imaging findings. Complications include hemopericardium, hemoperitoneum, coronary vessel injury, and phrenic nerve injury. Modern epicardial mapping techniques provide new understandings of the 3-dimensional nature of reentrant ventricular tachycardia circuits across cardiomyopathy etiologies. Where epicardial access is not feasible, alternative techniques to reach epicardial ventricular tachycardia sources may be necessary.

Novel dry pericardiocentesis: Transvenous puncture of the right ventricle with the back end of a 0.014-inch PTCA guidewire and a 1.8 Fr microcatheter

Background

Dry transthoracic pericardiocentesis is challenging and carries the risk of right ventricle (RV) or coronary artery injury. The RV can usually control bleeding automatically. For example, most perforations of the RV caused by pacemaker leads are treated without open surgery. Thus, we performed a transvenous puncture of the RV for dry pericardiocentesis with the back end of a 0.014-inch percutaneous transluminal coronary angioplasty (PTCA) guidewire and a 1.8 Fr microcatheter.

Methods

The back end of a 0.014-inch PTCA guidewire within a 1.8 Fr microcatheter was used to transvenously punctured through the middle of the acute margin of the RV into the pericardial space in 12 Yorkshire swine and 5 beagles. PTCA balloons of different diameters were used to dilate the puncture holes for 15 min under anticoagulation in all the animals to assess the ability of the RV to control the bleeding. Then, for 3 days, the puncture hole was dilated by a 6 Fr catheter in 9 swine and 5 dogs.

Results

The puncture was successful in all the animals. After withdrawal of the 2.5-mm balloon or the 6 Fr catheter, none of the animals exhibited pericardial effusion, as observed by echocardiography. There was no sustained ventricular arrhythmia or other complications. All the animals survived.

Conclusion

Transvenous puncture of the right ventricle with the back end of a 0.014-inch PTCA guidewire and 1.8 Fr microcatheter may be feasible and have a good safety margin.

2019 HRS/EHRA/APHRS/LAHRS expert consensus statement on catheter ablation of ventricular arrhythmias

Ventricular arrhythmias are an important cause of morbidity and mortality and come in a variety of forms, from single premature ventricular complexes to sustained ventricular tachycardia and fibrillation. Rapid developments have taken place over the past decade in our understanding of these arrhythmias and in our ability to diagnose and treat them. The field of catheter ablation has progressed with the development of new methods and tools, and with the publication of large clinical trials. Therefore, global cardiac electrophysiology professional societies undertook to outline recommendations and best practices for these procedures in a document that will update and replace the 2009 EHRA/HRS Expert Consensus on Catheter Ablation of Ventricular Arrhythmias. An expert writing group, after reviewing and discussing the literature, including a systematic review and meta-analysis published in conjunction with this document, and drawing on their own experience, drafted and voted on recommendations and summarized current knowledge and practice in the field. Each recommendation is presented in knowledge byte format and is accompanied by supportive text and references. Further sections provide a practical synopsis of the various techniques and of the specific ventricular arrhythmia sites and substrates encountered in the electrophysiology lab. The purpose of this document is to help electrophysiologists around the world to appropriately select patients for catheter ablation, to perform procedures in a safe and efficacious manner, and to provide follow-up and adjunctive care in order to obtain the best possible outcomes for patients with ventricular arrhythmias.

2019 HRS/EHRA/APHRS/LAHRS expert consensus statement on catheter ablation of ventricular arrhythmias

Ventricular arrhythmias are an important cause of morbidity and mortality and come in a variety of forms, from single premature ventricular complexes to sustained ventricular tachycardia and fibrillation. Rapid developments have taken place over the past decade in our understanding of these arrhythmias and in our ability to diagnose and treat them. The field of catheter ablation has progressed with the development of new methods and tools, and with the publication of large clinical trials. Therefore, global cardiac electrophysiology professional societies undertook to outline recommendations and best practices for these procedures in a document that will update and replace the 2009 EHRA/HRS Expert Consensus on Catheter Ablation of Ventricular Arrhythmias. An expert writing group, after reviewing and discussing the literature, including a systematic review and meta-analysis published in conjunction with this document, and drawing on their own experience, drafted and voted on recommendations and summarized current knowledge and practice in the field. Each recommendation is presented in knowledge byte format and is accompanied by supportive text and references. Further sections provide a practical synopsis of the various techniques and of the specific ventricular arrhythmia sites and substrates encountered in the electrophysiology lab. The purpose of this document is to help electrophysiologists around the world to appropriately select patients for catheter ablation, to perform procedures in a safe and efficacious manner, and to provide follow-up and adjunctive care in order to obtain the best possible outcomes for patients with ventricular arrhythmias.

2019 HRS/EHRA/APHRS/LAHRS expert consensus statement on catheter ablation of ventricular arrhythmias

Ventricular arrhythmias are an important cause of morbidity and mortality and come in a variety of forms, from single premature ventricular complexes to sustained ventricular tachycardia and fibrillation. Rapid developments have taken place over the past decade in our understanding of these arrhythmias and in our ability to diagnose and treat them. The field of catheter ablation has progressed with the development of new methods and tools, and with the publication of large clinical trials. Therefore, global cardiac electrophysiology professional societies undertook to outline recommendations and best practices for these procedures in a document that will update and replace the 2009 EHRA/HRS Expert Consensus on Catheter Ablation of Ventricular Arrhythmias. An expert writing group, after reviewing and discussing the literature, including a systematic review and meta-analysis published in conjunction with this document, and drawing on their own experience, drafted and voted on recommendations and summarized current knowledge and practice in the field. Each recommendation is presented in knowledge byte format and is accompanied by supportive text and references. Further sections provide a practical synopsis of the various techniques and of the specific ventricular arrhythmia sites and substrates encountered in the electrophysiology lab. The purpose of this document is to help electrophysiologists around the world to appropriately select patients for catheter ablation, to perform procedures in a safe and efficacious manner, and to provide follow-up and adjunctive care in order to obtain the best possible outcomes for patients with ventricular arrhythmias.

Anticoagulation and the risk of complications in ventricular tachycardia and premature ventricular complex ablation

BACKGROUND

Many patients undergoing ventricular tachycardia (VT) or premature ventricular complex (PVC) ablation receive antithrombotic medications.  Their uninterrupted use has the potential to affect complication rates. We assessed the incidence of complications in a large cohort of patients undergoing these procedures, according to antithrombotic medication use.

METHODS

From June 2014 to June 2016, 201 VT and PVC ablations were performed at a single center. We allocated patients to three groups: (A) anticoagulation group (international normalized ratio ≥ 1.5 or non-vitamin K anticoagulant or full-dose low-molecular-weight (LMW) heparin on day of procedure); (B) antithrombotic group (antiplatelet therapy and/or prophylactic LMW heparin on day of procedure); and (C) no antithrombotics group.  We assessed periprocedural complication rates in each group.  Multivariable analysis was performed.

RESULTS

Group A (47 patients) had 8.5% procedural complication rate: one stroke, one pseudoaneurysm, one femoral artery occlusion, and one access site hematoma. In this group, 37 patients had femoral arterial and 18 had epicardial access. In Group B (46 patients), the complication rate was 6.5%: two cardiac tamponades and one pericardial effusion without compromise. Group C (108 patients) had a 5.6% complication rate: three cardiac tamponades (with one periprocedural death and one concomitant gastric vessel injury), one pericardial effusion without compromise, one stomach perforation, and two access site hematomas. Multivariable analysis did not show any significant predictors of complications, though age approached significance.

CONCLUSIONS

Complication rates were not significantly different between groups. These findings suggest that VT and PVC ablation can be performed safely in patients with uninterrupted antithrombotic medications.

Practical Guide to Ablation for Epicardial Ventricular Tachycardia: When to Get Access, How to Deal with Anticoagulation and How to Prevent Complications

Epicardial ablation is needed to eliminate ventricular tachycardia (VT) in some patients with nonischaemic cardiomyopathy. The 12-lead electrocardiogram of VT, pre-procedural imaging and endocardial unipolar voltage maps can predict a high likelihood of epicardial substrate and VT. A septal VT substrate may preclude the need for epicardial access and mapping and can be identified with imaging, pacing and voltage mapping. Pericardial access is usually obtained prior to systemic anticoagulation or after reversal of systemic anticoagulation. A unique set of complications can be encountered with epicardial access, mapping and ablation, which include haemopericardium, phrenic nerve injury, damage to major coronary arteries and pericarditis. Anticipating, preventing and, if necessary, managing these complications are paramount for patient safety. Best practices are reviewed.

Complications of pericardiocentesis: A clinical synopsis

Pericardiocentesis (PC) is both a diagnostic and a potentially life-saving therapeutic procedure. Currently echocardiography-guided pericardiocentesis is considered the standard clinical practice in the treatment of large pericardial effusions and cardiac tamponade. Although considered relatively safe, this invasive procedure may be associated with certain risks and potentially serious complications. This review provides a summary of pericardiocentesis and a focused overview of the potential complications of this procedure.

Intentional right atrial exit for microcatheter infusion of pericardial carbon dioxide or iodinated contrast to facilitate sub-xiphoid access

OBJECTIVES

We test the safety of transatrial pericardial access using small catheters, infusion of carbon dioxide (CO2 ) or iodinated contrast to facilitate sub-xiphoid access, and catheter withdrawal under full anticoagulation.

BACKGROUND

Sub-xiphoid pericardial access is required for electrophysiological and structural heart interventions. If present, an effusion protects the heart from needle injury by separating the myocardium from the pericardium. However, if the pericardium is 'dry' then there is a significant risk of right ventricle or coronary artery laceration caused by the heart beating against the needle tip. Intentional right atrial exit is an alternative pericardial access route, through which contrast media could be infused to separate pericardial layers.

METHODS

Transatrial pericardial access was obtained in a total of 30 Yorkshire swine using 4Fr or 2.8Fr catheters. In 16 animals, transatrial catheters were withdrawn under anticoagulation and MRI was performed to monitor for pericardial hemorrhage. In 14 animals, iodinated contrast or CO2 was infused before sub-xiphoid access was obtained.

RESULTS

Small effusions (mean 18.5 ml) were observed after 4Fr (1.3 mm outer-diameter) but not after 2.8Fr (0.9 mm outer-diameter) transatrial catheter withdrawal despite full anticoagulation (mean activated clotting time 383 sec), with no hemodynamic compromise. Pericardial CO2 resorbed spontaneously within 15 min.

CONCLUSIONS

Intentional transatrial exit into the pericardium using small catheters is safe and permits infusion of CO2 or iodinated contrast to separate pericardial layers and facilitate sub-xiphoid access. This reduces the risk of right ventricular or coronary artery laceration. 2.8Fr transatrial catheter withdrawal does not cause any pericardial hemorrhage, even under full anticoagulation.

How to recognize epicardial origin of ventricular tachycardias?

Percutaneous pericardial access for epicardial mapping and ablation of ventricular arrhythmias has expanded considerably in recent years. After its description in patients with Chagas disease, the technique has provided relevant in-formation on the arrhythmia substrate in other cardiomyopathies and has improved the results of ablation procedures in various clinical settings. Electrocardiographic criteria proposed for the recognition of the epicardial origin of ventricular tachycardias are mainly based on analysis of the first QRS components. Ventricular activation at the epicardium has a slow initial component reflecting the transmural activation and influenced by the absence of Purkinje system in the epicardium. Various parameters (pseudodelta wave, intrinsicoid deflection and shortest RS interval) of these initial intervals predict an epicardial origin in patients with scar-related ventricular tachycardias with right bundle branch block morphology. Using the same concept, the maximum deflection index was defined for the location of idiopathic epicardial tachycardias remote from the aortic root. Electrocardiogram criteria based on the morphology of the first component of the QRS (q wave in lead I) have been proposed in patients with nonischemic cardiomyopathy. All these criteria seem to be substrate-specific and have several limitations. Other information, including type of underlying heart disease, previous failed endocardial ablation, and evidence of epicardial scar on magnetic resonance imaging, can help to plan the ablation procedure and decide on an epicardial approach.