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Concept: Atrial flutter

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Heat shock protein (HSP) 27 is related to the pathogenesis of AF. However, the clinical relationship between HSP27 and AF is unclear. The present study was conducted to determine the clinical relationship between HSP27 and atrial fibrillation (AF).

Concepts: Present, Atrial fibrillation, Atrial flutter, Heat shock protein, Hsp27

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The classic cut and sew maze is thought to reduce stroke, in part because of left atrial appendage (LAA) elimination. Multiple LAA elimination techniques have evolved with the introduction of new surgical treatment options for atrial fibrillation (AF), but the impact on stroke remains unknown. We studied the rate of late neurologic event (LNE) in the era of contemporary AF surgery.

Concepts: Medicine, Hospital, Atrial fibrillation, Surgery, Neurosurgery, Atrial flutter, Left atrial appendage occlusion, Left atrial appendage

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BACKGROUND: Atrial fibrillation (AF) recurrence after ablation is difficult to predict. The development of AF is associated with inflammation, and inflammatory markers such as big endothelin-1 (big ET-1) reflect inflammatory status. It is unknown, however, whether big ET-1 can be used as a predictor for AF recurrence. The aim of this study was to investigate the relationship between plasma levels of big ET-1 and AF recurrence. METHODS: A total of 158 patients who had undergone primary ablation for symptomatic and/or drug-refractory AF, including 103 with paroxysmal and 55 with persistent AF, were included in this study. Left atrial diameter was measured with echocardiography and plasma big ET-1 levels with ELISA. All patients were followed up for at least 12 months and AF recurrence defined as an episode of AF lasting ≥ 30 s, with or without atrial flutter or atrial tachycardia. RESULTS: The AF recurrence rate was 44.9% (71/158) during the median follow-up period of 22 (13, 40) months. Plasma levels of big ET-1 in the recurrence group were higher than those in the non-recurrence group in all patients [0.80 (0.54, 1.30) vs. 0.57 (0.48, 0.72) fmol·L(-) (1), p  = 0.001], in patients with paroxysmal AF [0.81 (0.46, 1.30) vs. 0.57 (0.48, 0.70) fmol·L(-) (1), p  = 0.009] as well as in patients with persistent AF [0.77 (0.57, 1.28) vs. 0.57 (0.49, 0.89) fmol·L(-) (1), p = 0.034]. Multiple logistic regression analyses showed that plasma levels of big ET-1 were associated with AF recurrence in patients with paroxysmal AF (p  = 0.037). Kaplan-Meier analysis demonstrated that the sinus rhythm maintenance rate was lower in patients with higher big ET-1 levels than those with lower levels (p  < 0.05). CONCLUSIONS: Baseline plasma big ET-1 levels are associated with AF recurrence after primary ablation procedure in patients with paroxysmal AF, and may be used in the prediction of AF recurrence in these patients.

Concepts: Regression analysis, Logistic regression, Atrial fibrillation, Cardiac electrophysiology, Supraventricular tachycardia, Atrial flutter, Tachycardia, Left atrial appendage

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The anatomical and functional characteristics of the left atrial appendage (LAA) and its relationships with anatomical remodeling and ischemic stroke in patients with atrial fibrillation (AF) have not been clearly established. The purpose of this study was to determine whether functional and morphological features of the LAA independently predict clinical outcome and stroke in patients with AF who underwent catheter ablation (CA). Two hundred sixty-four patients with AF, including 176 with paroxysmal AF (PAF, 54.0 ± 11.4 years old, M:F = 138:38) and 88 with persistent AF (PeAF, 56.4 ± 9.6 years old, M:F = 74:14) were studied. Of these patients, 31 (11.7 %) had a history of stroke/TIA (transient ischemic attack). The LA and LAA volumes were 124.0 ± 42.4 and 24.9 ± 4.3 ml in PeAF, these values were greater than those in PAF (81.2 ± 24.8 ml and 21.2 ± 5.1 ml, P < 0.001). The AF type (P = 0.016) and AF duration (P = 0.005), and anti-arrhythmic drugs use (P < 0.001) were significant predictors of AF recurrence after CA in all patients. Compared with patients without history of stroke, stroke patients had larger LA volume (106.9 ± 23.0 vs. 94.0 ± 38.9 ml, P = 0.004) and had lower LAA EF (50.0 ± 11.0 vs. 65.7 ± 13.4 %, P < 0.001). The independent predictors of stroke were age (P = 0.002) and LAA EF (P < 0.001) in PAF patients and that was only age (P = 0.001) in PeAF patients. In anatomical and morphological parameters of the LA and LAA, only depressed systolic function of the LAA was significantly related to stroke/TIA and recurrence of AF after CA in paroxysmal AF patients. Further large scaled prospective study is required for validation.

Concepts: Stroke, Atrial fibrillation, Transient ischemic attack, Blood pressure, Atrial flutter, Cultural studies, Left atrial appendage occlusion, Left atrial appendage

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OBJECTIVE: Describe the electrophysiological characteristics in subjects with asymptomatic Wolff-Parkinson-White with sports activities or high professional responsibility. METHODS: Nineteen subjects, mean age 33±13 years (group A). The electrophysiological characteristics were compared with a matched group with symptomatic WPW (group B). RESULTS: At baseline the anterograde refractory period and the anterograde conduction 1:1 over the accessory pathway were longer in group A (300±48ms vs 262±32ms, p<0.05 and 355±108ms vs 307±86ms, p<0.05), respectively. None of group A had a anterograde refractory period<250ms and 58% showed absence of retrograde conduction over the accessory pathway vs 4% of group B (p<0.001). Induction of tachycardia was significantly less in group A (5%) than in group B (92%) (p<0.001). Atrial fibrillation was induced in only one of group A vs 32% of group B (p<0.001). CONCLUSION: We confirm the benign electrophysiological characteristics in asymptomatic compared to symptomatic subjects. Poor anterograde conduction along with absence of retrograde conduction explains the low frequency of tachyarrhythmias and would not support the routine investigation of all asymptomatic subjects. But, due to possible consequences, remains the systematic indication for preventive ablation in the subgroup of asymptomatic subjects with sporting activities or high professional responsibility.

Concepts: Atrial fibrillation, Cardiac electrophysiology, Supraventricular tachycardia, Atrial flutter, Orgasm, Asymptomatic, Tachycardia, Wolff-Parkinson-White syndrome

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AIMS: Orthodromic atrioventricular reentrant tachycardia (ORT) is the most common arrhythmia at electrophysiological study (EPS) in patients with pre-excitation. The purpose of the study was to determine the clinical significance and the electrophysiological characteristics of patients with inducible antidromic tachycardia (ADT).METHODS AND RESULTS: Electrophysiological study was performed in 807 patients with a pre-excitation syndrome in control state and after isoproterenol. Antidromic tachycardia was induced in 63 patients (8%). Clinical and electrophysiological data were compared with those of 744 patients without ADT. Patients with and without ADT were similar in term of age (33 ± 18 vs. 34 ± 17), male gender (68 vs. 61%), clinical presentation with spontaneous atrioventricular reentrant tachycardia (AVRT) (35 vs. 42%), atrial fibrillation (AF) (3 vs. 3%), syncope (16 vs. 12%). In patients with induced ADT, asymptomatic patients were less frequent (24 vs. 37%; <0.04), spontaneous ADT and spontaneous malignant form more frequent (8 vs. 0.5%; <0.001) (16 vs. 6%; <0.002). Left lateral accessory pathway (AP) location was more frequent (51 vs. 36%; P < 0.022), septal location less frequent (40 vs. 56%; P < 0.01). And 1/1 conduction through AP was more rapid. Orthodromic AVRT induction was as frequent (55.5 vs. 55%), but AF induction (41 vs. 24%; P < 0.002) and electrophysiological malignant form were more frequent (22 vs. 12%; P < 0.02). The follow-up was similar; four deaths and three spontaneous malignant forms occurred in patients without ADT. When population was divided based on age (<20/≥20 years), the older group was less likely to have criteria for malignant form.CONCLUSION: Antidromic tachycardia induction is rare in pre-excitation syndrome and generally is associated with spontaneous or electrophysiological malignant form, but clinical outcome does not differ.

Concepts: Atrial fibrillation, Supraventricular tachycardia, Atrial flutter, Neurophysiology, Asymptomatic, Tachycardia, Wolff-Parkinson-White syndrome, AV nodal reentrant tachycardia

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The purpose of this study was to investigate the frequency and clinical impact of incomplete left atrial appendage (LAA) sealing and consequent peri-device residual blood flow in patients undergoing percutaneous LAA closure with the Watchman device (Atritech, Inc., Plymouth, Minnesota).

Concepts: Heart, Stroke, Atrial fibrillation, Warfarin, Atrial flutter, Anticoagulant, Left atrial appendage occlusion, Left atrial appendage

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BACKGROUND: Many patients who develop atrial fibrillation (AF) will experience a worsening of their arrhythmia over time. The optimal time to proceed with catheter ablation during the disease course is unknown. Further, it is unknown if delays in treatment will negatively influence outcomes. METHODS: A total of 4,535 consecutive patients who underwent an AF ablation procedure that had long-term established care within an integrated health care system were evaluated. Recursive partitioning was used to determine categories associated with changes in risk from the time of first AF diagnosis to first AF ablation: 1:30-180(n=1,152), 2:181-545(n=856), 3:546-1825(n=1,326), 4:>1825(n=1,201) days). Outcomes evaluated include 1 year AF recurrence, stroke, heart failure hospitalization, and death. RESULTS: With increasing time to treatment, surprisingly patients were older (1: 63.7±11.1, 2: 62.6±11.8, 3: 66.4±10.2, 4: 67.6±9.7, p<0.0001) and had more hypertension (1:53.0%, 2:59.0%, 3:53.8%, 4:39.0%, p<0.0001). For each strata of time increase, there was a direct increase of 1 year AF recurrence (1:19.4%, 2: 23.4%, 3:24.9%, 4:24.0%, p-trend = 0.02). After adjustment, clinically significant differences in risk of recurrent AF were found when compared to the 30-180 day time category: 181-545: odd ratio(OR)=1.23, p=0.08; 546-1825: OR=1.27, p=0.02; and >1825: OR=1.25, p=0.05. No differences were observed for 1 year stroke among the groups. Death (1:2.1%, 2:3.9%, 3:5.7%, 4:4.4%, p-trend=0.001) and heart failure hospitalization (1:2.6%, 2:4.1%, 3:5.4%, 4:4.4%, p-trend=0.009) rates at 1 year were higher in the most delayed groups. CONCLUSIONS: Delays in treatment with catheter ablation impact procedural success rates independent of temporal changes to the AF subtype at ablation.

Concepts: Hypertension, Cardiology, Heart, Stroke, Atrial fibrillation, Cardiac electrophysiology, Atrial flutter, Object-oriented programming

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Obesity is repeatedly emphasized as a risk factor for atrial fibrillation or flutter (AF). However, the underlying evidence may be questioned, as the obvious correlations between various anthropometric measures hamper identification of the characteristics that are biologically driving AF risk, and recent studies suggest that fat carries limited or no independent risk of AF.

Concepts: Heart, Atrial fibrillation, Anthropometry, Atrial flutter, Body shape

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Background Current guidelines recommend pulmonary-vein isolation by means of catheter ablation as treatment for drug-refractory paroxysmal atrial fibrillation. Radiofrequency ablation is the most common method, and cryoballoon ablation is the second most frequently used technology. Methods We conducted a multicenter, randomized trial to determine whether cryoballoon ablation was noninferior to radiofrequency ablation in symptomatic patients with drug-refractory paroxysmal atrial fibrillation. The primary efficacy end point in a time-to-event analysis was the first documented clinical failure (recurrence of atrial fibrillation, occurrence of atrial flutter or atrial tachycardia, use of antiarrhythmic drugs, or repeat ablation) following a 90-day period after the index ablation. The noninferiority margin was prespecified as a hazard ratio of 1.43. The primary safety end point was a composite of death, cerebrovascular events, or serious treatment-related adverse events. Results A total of 762 patients underwent randomization (378 assigned to cryoballoon ablation and 384 assigned to radiofrequency ablation). The mean duration of follow-up was 1.5 years. The primary efficacy end point occurred in 138 patients in the cryoballoon group and in 143 in the radiofrequency group (1-year Kaplan-Meier event rate estimates, 34.6% and 35.9%, respectively; hazard ratio, 0.96; 95% confidence interval [CI], 0.76 to 1.22; P<0.001 for noninferiority). The primary safety end point occurred in 40 patients in the cryoballoon group and in 51 patients in the radiofrequency group (1-year Kaplan-Meier event rate estimates, 10.2% and 12.8%, respectively; hazard ratio, 0.78; 95% CI, 0.52 to 1.18; P=0.24). Conclusions In this randomized trial, cryoballoon ablation was noninferior to radiofrequency ablation with respect to efficacy for the treatment of patients with drug-refractory paroxysmal atrial fibrillation, and there was no significant difference between the two methods with regard to overall safety. (Funded by Medtronic; FIRE AND ICE ClinicalTrials.gov number, NCT01490814 .).

Concepts: Atrial fibrillation, Cardiac electrophysiology, Supraventricular tachycardia, Atrial flutter, Amiodarone, Digoxin, Radiofrequency ablation, Wolff-Parkinson-White syndrome