The Netherlands Arrhythmogenic Cardiomyopathy Registry: design and status update.

BACKGROUND: Clinical research on arrhythmogenic cardiomyopathy (ACM) is typically limited by small patient numbers, retrospective study designs, and inconsistent definitions. AIM: To create a large national ACM patient cohort with a vast amount of uniformly collected high-quality data that is readily available for future research. METHODS: This is a multicentre, longitudinal, observational cohort study that includes (1) patients with a definite ACM diagnosis, (2) at-risk relatives of ACM patients, and (3) ACM-associated mutation carriers. At baseline and every follow-up visit, a medical history as well information regarding (non-)invasive tests is collected (e. g. electrocardiograms, Holter recordings, imaging and electrophysiological studies, pathology reports, etc.). Outcome data include (non-)sustained ventricular and atrial arrhythmias, heart failure, and (cardiac) death. Data are collected on a research electronic data capture (REDCap) platform in which every participating centre has its own restricted data access group, thus empowering local studies while facilitating data sharing. DISCUSSION: The Netherlands ACM Registry is a national observational cohort study of ACM patients and relatives. Prospective and retrospective data are obtained at multiple time points, enabling both cross-sectional and longitudinal research in a hypothesis-generating approach that extends beyond one specific research question. In so doing, this registry aims to (1) increase the scientific knowledge base on disease mechanisms, genetics, and novel diagnostic and treatment strategies of ACM; and (2) provide education for physicians and patients concerning ACM, e. g. through our website ( www.acmregistry.nl ) and patient conferences.

Integrated whole-heart computational workflow for inverse potential mapping and personalized simulations.

BACKGROUND: Integration of whole-heart activation simulations and inverse potential mapping (IPM) could benefit the guidance and planning of electrophysiological procedures. Routine clinical application requires a fast and adaptable workflow. These requirements limit clinical translation of existing simulation models. This study proposes a comprehensive finite element model (FEM) based whole-heart computational workflow suitable for IPM and simulations. METHODS: Three volunteers and eight patients with premature ventricular contractions underwent body surface potential (BSP) acquisition followed by a cardiac MRI (CMR) scan. The cardiac volumes were segmented from the CMR images using custom written software. The feasibility to integrate tissue-characteristics was assessed by generating meshes with virtual edema and scar. Isochronal activation maps were constructed by identifying the fastest route through the cardiac volume using the Möller-Trumbore and Floyd-Warshall algorithms. IPM's were reconstructed from the BSP's. RESULTS: Whole-heart computational meshes were generated within seconds. The first point of atrial activation on IPM was located near the crista terminalis of the superior vena cave into the right atrium. The IPM demonstrated the ventricular epicardial breakthrough at the attachment of the moderator band with the right ventricular free wall. Simulations of sinus rhythm were successfully performed. The conduction through the virtual edema and scar meshes demonstrated delayed activation or a complete conductional block respectively. CONCLUSION: The proposed FEM based whole-heart computational workflow offers an integrated platform for cardiac electrical assessment using simulations and IPM. This workflow can incorporate patient-specific electrical parameters, perform whole-heart cardiac activation simulations and accurately reconstruct cardiac activation sequences from BSP's.

Tachyarrhythmia in patients with congenital heart disease: inevitable destiny?

The prevalence of patients with congenital heart disease (CHD) has increased over the last century. As a result, the number of CHD patients presenting with late, postoperative tachyarrhythmias has increased as well. The aim of this review is to discuss the present knowledge on the mechanisms underlying both atrial and ventricular tachyarrhythmia in patients with CHD and the advantages and disadvantages of the currently available invasive treatment modalities.

Endovascular catheter ablation of ventricular tachycardia in a patient with a surgically repaired congenital left ventricular aneurysm.

We present a patient with a congenital left ventricular aneurysm who visited our outpatient clinic for a routine check-up and, during this visit, lost consciousness due to sustained ventricular tachycardia. In our patient, endocardial mapping revealed extensive conduction abnormalities, and successful ablation was accomplished at the endocardial surface.

The future of atrial fibrillation therapy: intervention on heat shock proteins influencing electropathology is the next in line.

Atrial fibrillation (AF) is the most common age-related cardiac arrhythmia accounting for one-third of hospitalisations. Treatment of AF is difficult, which is rooted in the progressive nature of electrical and structural remodelling, called electropathology, which makes the atria more vulnerable for AF. Importantly, structural damage of the myocardium is already present when AF is diagnosed for the first time. Currently, no effective therapy is known that can resolve this damage.Previously, we observed that exhaustion of cardioprotective heat shock proteins (HSPs) contributes to structural damage in AF patients. Also, boosting of HSPs, by the heat shock factor-1 activator geranylgeranylacetone, halted AF initiation and progression in experimental cardiomyocyte and dog models for AF. However, it is still unclear whether induction of HSPs also prolongs the arrhythmia-free interval after, for example, cardioversion of AF.In this review, we discuss the role of HSPs in the pathophysiology of AF and give an outline of the HALT&REVERSE project, initiated by the HALT&REVERSE Consortium and the AF Innovation Platform. This project will elucidate whether HSPs (1) reverse cardiomyocyte electropathology and thereby halt AF initiation and progression and (2) represent novel biomarkers that predict the outcome of AF conversion and/or occurrence of post-surgery AF.

Atrial fibrillation: to map or not to map?

Isolation of the pulmonary veins may be an effective treatment modality for eliminating atrial fibrillation (AF) episodes but unfortunately not for all patients. When ablative therapy fails, it is assumed that AF has progressed from a trigger-driven to a substrate-mediated arrhythmia. The effect of radiofrequency ablation on persistent AF can be attributed to various mechanisms, including elimination of the trigger, modification of the arrhythmogenic substrate, interruption of crucial pathways of conduction, atrial debulking, or atrial denervation. This review discusses the possible effects of pulmonary vein isolation on the fibrillatory process and the necessity of cardiac mapping in order to comprehend the mechanisms of AF in the individual patient and to select the optimal treatment modality.

Antiarrhythmic drugs management in patients with atrial fibrillation: the new guidelines.

Antiarrhythmic drug therapy will continue to play an important role in the treatment of atrial fibrillation (AF). Pharmacological therapy is focused on AF symptom relief and on prevention of tachycardiomyopathy. The choice between the various anti-arrhythmic drugs available, either for rate or rhythm control, mainly depends on the underlying cardiac disease, type of AF and possible side-effects. New anti-arrhythmic drugs in the guidelines vernakalant and dronedarone are promising, but further research is required to explore their role in treatment of patients with AF. In this review, we will discuss the role of antiarrhythmic drugs in management of patients with AF according to the new AF guidelines of the European Society of Cardiology.

[Atrio-oesophageal fistula after thoracoscopic treatment of atrial fibrillation]. / Atrio-oesofageale fisteling na thoracoscopische behandeling van atriumfibrilleren.

BACKGROUND: An atrio-oesophageal fistula (AOF) is a rare but severe complication of radiofrequency ablation during video-assisted thoracoscopic pulmonary vein isolation (VATS-PVI). CASE DESCRIPTION: A 68-year-old man presented to the emergency department with reduced general well-being and a fever. Eight weeks prior he had undergone a VATS-PVI. Blood results revealed elevated inflammatory parameters, and blood cultures were positive for Streptococcus anginosus. A CT-scan demonstrated an air configuration in the left atrium. Shortly after this he developed a left-sided hemiparesis. As a cerebral air embolus due to an AOF was suspected, we decided to operate. The defects in the atrium and the oesophagus were closed primarily during open-heart surgery. CONCLUSION: An AOF is a rare complication following a VATS-PVI. Patients often present with non-specific symptoms like a fever. It is important to be alert of this complication after a VATS-PVI and to perform early diagnostic imaging.

The impact of an implantable cardioverter defibrillator: the Leiden follow-up study of ICD patients and their partners.

OBJECTIVES: The goal of this study was to evaluate 1) the presence of psychosocial problems in both ICD patients and their partners, and 2) the relation between psychosocial problems and various clinical variables. METHODS: Questionnaires were sent to 219 ICD patients and their partners. RESULTS: Sixty-eight percent of the ICD patients, 122 (81%) male, aged 59±12 years, and 62% of their partners, 28 (21%) male, aged 58±11 years, returned the questionnaires. Anxiety, depression or nervousness was reported by 49%, 30% and 52% respectively of the patients and by 36%, 24% and 66% of the partners. In patients, mental health problems were associated with a lower left ventricular ejection fraction (p=0.006), younger age (p=0.029), employment (p=0.011), unpleasant experiences from ICD discharges (p=0.032), prior myocardial infarction (p=0.019) and a higher NYHA functional class (p=0.05). Nervousness was more often reported by partners of ICD patients with prior myocardial infarction (p=0.049). Sixty percent of the partners had a need for counselling or support groups. CONCLUSION: Psychosocial problems are present in ICD patients and their partners and are associated with a number of clinical variables. A specific ICD rehabilitation programme should therefore not only be offered to ICD patients but to their partners as well.

Multimodality imaging for patient evaluation and guidance of catheter ablation for atrial fibrillation - current status and future perspective.

Left atrial catheter ablation is an established non-pharmacological therapy for the treatment of atrial fibrillation. The importance of a noninvasive multimodality imaging approach is emphasized by the current guidelines for the various phases of the ablation work-up e.g. patient identification, therapy guidance and procedural evaluation. Advances in the capabilities of imaging modalities and the increasing cost of healthcare warrant a review of the multimodality approach. This review discusses the application of cardiac imaging for pulmonary vein and left atrial ablation divided into stages: pre-procedural stage (assessment of left atrial dimensions, left atrial appendage thrombus and pulmonary vein anatomy), peri-procedural stage (integration of anatomical and electrical information) and post-procedural stage (evaluation of efficacy by assessment of tissue properties). Each section is dedicated to one of the subtopics of a stage, allowing a thorough comparison to be made between the strengths and weaknesses of the different imaging modalities and the identification of one that exhibits the potential for a single technique approach.

Adenosine testing after cryoballoon pulmonary vein isolation improves long-term clinical outcome.

BACKGROUND: Adenosine infusion after pulmonary vein isolation (PVI) with radiofrequency energy reveals dormant muscular sleeves and predicts atrial fibrillation (AF) recurrence. The aim of our study was to determine whether adenosine could reveal dormant PV sleeves after cryoballoon isolation and study its effect on long-term recurrence of AF. METHODS: Patients with paroxysmal AF underwent cryoballoon PVI. After PVI, adenosine 25 mg was infused to test for dormant muscular sleeves in each vein. If reconnection under adenosine was shown, further cryoballoon ablation was performed until no more reconnection occurred. Follow-up was performed with ECG, 24-h Holter recording, and a symptom questionnaire at three monthly intervals. Transtelephonic Holter monitoring was performed for 1 month before and 3 months after PVI. Patients who underwent cryoballoon PVI without adenosine administration were used as controls for comparison. RESULTS: In the study group (n = 34, 24 males), adenosine revealed dormant sleeves in 9/132 (8 %) veins, and 7/34 (21 %) patients. All but one vein was further treated until the dormant sleeves were isolated. During a mean follow-up of 520 ± 147 days, 23/34 (68 %) patients were free of AF without antiarrhythmic drugs (AADs). In the control group (n = 65, 46 males), 29/65 (46 %) were free of AF without AADs. There were significantly less AF recurrences in the study group (p = 0.04). CONCLUSIONS: Adenosine administration after cryoballoon PVI reveals dormant muscular sleeves in 21 % of patients. Clinical follow-up shows that adenosine testing is effective in reducing AF recurrence after cryoballoon ablation.