High Cerebrovascular Thromboembolic Event Rate Long after Unsuccessful Catheter Ablation for Atrial Fibrillation.

BACKGROUND: Although catheter ablation (CA) is an accepted therapeutic option for atrial fibrillation (AF), data is lacking concerning the long-term thromboembolic event (TE) and mortality rate of patients after unsuccessful CA for AF. OBJECTIVE: The aim of the current study was to detect the long-term TE and mortality rate of patients with successful CA (group A) of AF and compared those with unsuccessful ablation (group B). METHODS: Following a 4-years of follow-up (FU) 330 patients were included into the groupA, and 105 patients into the group B. Primary outcome was defined as all stroke/TIA occurrence. Secondary outcome was considered as all-cause mortality and stroke - and TIA only occurrence. RESULTS: Seventeen patients developed a stroke/TIA during a median of 5.8 [5.1-7.3] years of FU. In the group A 8 (2.4%) patients developed a stroke/TIA during a FU of 2037 person-years (incidence rate 3.92 per 1000 person-years), compared to 9 patients in the group B during a FU of 726 person-years (incidence rate 12.4 per 1000 person-years). The crude HR for primary outcome was 2.84 (95% CI 1.078-7.48) in the group B compared with the group A. Cumulative TIA-alone incidence (3.97, CI 1.10-14.34, p=0.035) and the annualized TIA-alone incidence rate was significantly higher in the group B. (p=0.029). Neither the mortality rate nor the incidence rate of stroke-alone differed significantly among the groups. CONCLUSIONS: The risk of all stroke/TIA and TIA-alone is higher among patients after unsuccessful CA of AF compared to those after successful ablation.

Coupling interval variability of premature ventricular contractions in patients with different underlying pathology: an insight into the arrhythmia mechanism.

PURPOSE: Coupling interval (CI) variability of premature ventricular contractions (PVCs) is influenced by the underlying arrhythmia mechanism. The aim of this study was to compare CI variability of PVCs in different myocardial disease entities, in order to gain insight into their arrhythmia mechanism. METHODS: Sixty-four patients with four underlying pathologies were included: idiopathic (n = 16), non-ischemic dilated cardiomyopathy (NIDCM) (n = 16), familial cardiomyopathy (PLN/LMNA) (n = 16), and post-MI (n = 16)-associated PVCs. The post-MI group was included as a reference, on account of its known re-entry mechanism. On Holter registrations, the first 20 CIs of the dominant PVC morphology were measured manually after which median ΔCI and mean SD of CI/√R-R (= CI of PVC corrected for underlying heart rate) were obtained. Two observers independently measured PVC CIs on pre-selected Holter registrations in order to determine inter- and intra-observer reliability. RESULTS: The largest ΔCI was seen in the PLN/LMNA group (220 ms (120-295)), the lowest in the idiopathic group (120 ms (100-190)). The ΔCI in the PLN/LMNA group was significantly larger than the post-MI group (220 ms (120-295) vs 130 ms (105-155), p = 0.023). Mean SD of CI/√R-R in the PLN/LMNA group was also significantly higher than in the post-MI group (p = 0.044). Inter- and intra-observer reliability was good (ICC = 0.91 vs 0.86 and 0.96 vs 0.77, respectively). CONCLUSIONS: Low ΔCI and SD of CI/√R-R of idiopathic and NIDCM PVCs suggest that the underlying arrhythmia mechanisms might be re-entry or triggered activity. Abnormal automaticity or modulated parasystole are unlikely mechanisms. High CI variability in PLN/LMNA patients suggests that the re-entry and triggered activity are less likely mechanisms in this group.

Comparison of long-term outcome between patients aged < 65 years vs. ≥ 65 years after atrial fibrillation ablation.

BACKGROUND: Atrial fibrillation (AF) is the most frequent arrhythmia, and its prevalence is increasing with aging. We aimed to compare the long-term outcome data of patients < 65 years vs. ≥ 65 years who underwent catheter ablation (CA) for drug-refractory AF. METHODS: Consecutive patients with primary pulmonary vein isolation performed between March 2001 and December 2011, and those who completed a five-year of follow-up were divided into two groups: patients aged < 65 years into group 1, and patients aged ≥ 65 into group 2. Long-term outcome data concerning mortality, thromboembolic events (TE) and success rates were compared between these groups. RESULTS: A total number of 390 patients were included, group 1 contained 310 patients, and 80 patients in group 2. In group 2, patients had more often impaired renal function (P < 0.001) and thyroid disease (P = 0.047). A total of fifteen patients died during the 6.63 ± 2.1 years of follow-up, with a significantly higher incidence in the older group (8/80 vs. 7/310 patients, P = 0.004). The majority of fatal outcome was due to cancerous diseases in both groups. No difference was observed concerning the long-term TE rate (12/310 vs. 4/80 patients, P = 0.75). Rhythm control failed in 25.9% of the patients, with no difference between the groups: 26.4% in group 1 vs. 23.7% in group 2 (P = 0.67). CONCLUSIONS: Despite growing prevalence of AF in aging population, the elderly patients are underrepresented in CA procedures. Similar clinical success and TE complication rate are observed between the age-groups. Our data suggest more liberal criteria might be applied while selecting patients for AF ablation.

Perservative paroxysmal atrioventricular block : Cardiac syncope misdiagnosed as anxiety for more than 20 years.

A 42-year-old woman was referred for cardiac diagnostic work-up of loss of recurrent consciousness over the past 25 years. She received medication with an anxiolytic, an antidepressant, and a neuroleptic drug. After a normal resting ECG, there were 112 episodes of paroxysmal atrioventricular block III° in her 24 h Holter recording with asystole for up to 27 s. The patient was symptomatic only once with dizziness due to an asystole of 8.8 s while she was awake in the early morning. After DDDR pacemaker implantation, the patient was asymptomatic during the following 2 years. This case illustrates the complex and not fully understood problem of paroxysmal AV block, in this instance neither intrinsic, nor phase 4 or vagally induced. It further reminds us to carefully clarify the cause of loss of consciousness consistently which may render prolonged ECG monitoring necessary also in patients without heart disease.

Remote monitoring of heart failure: benefits for therapeutic decision making.

INTRODUCTION: Chronic heart failure is a cardiovascular disorder with high prevalence and incidence worldwide. The course of heart failure is characterized by periods of stability and instability. Decompensation of heart failure is associated with frequent and prolonged hospitalizations and it worsens the prognosis for the disease and increases cardiovascular mortality among affected patients. It is therefore important to monitor these patients carefully to reveal changes in their condition. Remote monitoring has been designed to facilitate an early detection of adverse events and to minimize regular follow-up visits for heart failure patients. Several new devices have been developed and introduced to the daily practice of cardiology departments worldwide. Areas covered: Currently, special tools and techniques are available to perform remote monitoring. Concurrently there are a number of modern cardiac implantable electronic devices that incorporate a remote monitoring function. All the techniques that have a remote monitoring function are discussed in this paper in detail. All the major studies on this subject have been selected for review of the recent data on remote monitoring of HF patients and demonstrate the role of remote monitoring in the therapeutic decision making for heart failure patients. Expert commentary: Remote monitoring represents a novel intensified follow-up strategy of heart failure management. Overall, theoretically, remote monitoring may play a crucial role in the early detection of heart failure progression and may improve the outcome of patients.

Cerebral micro-embolization during pulmonary vein isolation: Relation to post-ablation silent cerebral ischemia.

BACKGROUND: High incidences of silent cerebral ischemia (SCI) have been revealed by diffusion-weighted magnetic resonance imaging (DW MRI) after pulmonary vein isolation (PVI) for atrial fibrillation. A high number of mostly gaseous micro-embolic signals (MESs) was detected by transcranial Doppler (TCD) during PVI. In this investigation the possible relationship between MESs detected intraoperatively by TCD and new SCI on DW MRI post-ablation is reported. METHODS: 27 consecutive atrial fibrillation patients (6 female, age median: 64 interquartile range: 13.23) undergoing PVI with the pulmonary vein ablation catheter, pre- and post-ablation DW MRI and intra-operative MES detection by TCD were included in the study. Procedures were performed on a therapeutic international normalized ratio (2-3) and with a target activated clotting time ≥ 350 s in all patients. DW MRI scans performed pre- and post-ablation revealed new SCI in 6 out of 27 (22%) patients. RESULTS: The median (interquartile range) MES count recorded during the whole procedure was 1642 (912) in patients with and 1019 (529) in those without SCI (p = 0.129). The number of MESs recorded during pulmonary vein angiography was significantly higher in patients as compared to those without a new lesion on the post-ablation DW MRI: 257 (249) vs. 110 (71), respectively (p = 0.0009). On mul-tivariate logistic regression, the total MES count was predictive of SCI in patients older than 68 years. CONCLUSIONS: Micro-embolus generation detected by TCD during pulmonary vein angiography significantly correlates with new SCI on DW MRI post-ablation.

Phased RF Ablation: Results and Concerns.

Treatment of atrial fibrillation (AF) with catheter ablation has proven to be a safe and effective treatment modality which is offered to an increasing number of patients in many centers. Pulmonary vein isolation (PVI) is an established cornerstone of AF ablation strategies. Athough the isolation of the pulmonary veins (PVs) with irrigated focal radiofrequency (RF) catheters using a point-by-point method is considered as the gold standard, it can be challenging to create contiguous lesions, time consuming, and require advanced three dimensional (3D) mapping and navigational systems. The phased RF ablation system was designed to address many of these challenges associated with conventional focal RF ablation. In this review, we describe the main features of phased RF ablation and summarize the data available on clinical outcome with this technology.

Learning curve in circular multipolar phased radiofrequency ablation of atrial fibrillation.

BACKGROUND: Although atrial fibrillation (AF) ablation is considered a technically challenging procedure, studies on the learning curve of different pulmonary vein isolation (PVI) techniques are limited. We investigated the time-dependent changes in procedural parameters, complication rates, and in the 1-year clinical outcome during our initial experience with circular multipolar phased radiofrequency (RF) ablation. METHODS AND RESULTS: The first 132 consecutive patients (40 female; age: 56.6 ± 10.4 years) who underwent PVI with phased RF ablation for paroxysmal or persistent AF at our center were included in the study. Procedural parameters and atrial arrhythmia-free survival were compared in the first, second and third group of 44 successive patients. All pulmonary veins were successfully isolated in 44 (100%), 41 (93.8%) and 42 (95.5%) patients in Tierce 1, 2 and 3, respectively (p = 0.233). The number of RF applications (per vein) required for isolation and fluoroscopy times demonstrated a significant decrease with experience, and a trend towards lower procedure times in Tierces 2 and 3 was also observed. Atrial arrhythmia-free survival rates at 12 months postablation were 68.18%, 75%, and 70.75% in Tierce 1, Tierce 2 and Tierce 3, respectively (p = 0.772). Pericardial tamponade requiring percutaneous subxiphoid drainage occurred in 1 patient (Tierce 3) as the only significant procedural complication. CONCLUSIONS: A learning curve effect was demonstrated in fluoroscopy times and in the number of RF applications but not in the acute success and in the long-term arrhythmia-free survival with circular multipolar RF ablations.