Recent-onset atrial fibrillation: a study exploring the elements of Virchow's triad after cardioversion.

PURPOSE: Atrial fibrillation (AF) imposes an inherent risk for stroke and silent cerebral emboli, partly related to left atrial (LA) remodeling and activation of inflammatory and coagulation systems. The aim was to explore the effects of cardioversion (CV) and short-lasting AF on left atrial hemodynamics, inflammatory, coagulative and cardiac biomarkers, and the association between LA functional recovery and the presence of a prior history of AF. METHODS: Patients referred for CV within 48 h after AF onset were prospectively included. Echocardiography and blood sampling were performed immediately prior, 1-3 h after, and at 7-10 days after CV. The presence of chronic white matter hyperintensities (WMH) on magnetic resonance imaging was related to biomarker levels. RESULTS: Forty-three patients (84% males), aged 55±9.6 years, with median CHA2DS2-VASc score 1 (IQR 0-1) were included. The LA emptying fraction (LAEF), LA peak longitudinal strain during reservoir, conduit, and contractile phases improved significantly after CV. Only LAEF normalized within 10 days. Interleukin-6, high-sensitivity cardiac-troponin-T (hs-cTNT), N-terminal-pro-brain-natriuretic peptide, prothrombin-fragment 1+2 (PTf1+2), and fibrinogen decreased significantly after CV. There was a trend towards higher C-reactive protein, hs-cTNT, and PTf1+2 levels in patients with WMH (n=21) compared to those without (n=22). At 7-10 days, the LAEF was significantly lower in patients with a prior history of AF versus those without. CONCLUSION: Although LA stunning resolved within 10 days, LAEF remained significantly lower in patients with a prior history of AF versus those without. Inflammatory and coagulative biomarkers were higher before CV, but subsided after 7-10 days, which altogether might suggest an enhanced thrombogenicity, even in these low-risk patients.

Serial Magnetic Resonance Imaging after Electrical Cardioversion of Recent Onset Atrial Fibrillation in Anticoagulant-Naïve Patients - A Prospective Study Exploring Clinically Silent Cerebral Lesions.

BACKGROUND: Patients with atrial fibrillation (AF) have a high incidence of cognitive impairment, which may be related to clinically silent microembolism causing cerebral infarctions. OBJECTIVE: To explore the occurrence and timing of silent brain lesions following electrical cardioversion (CV) of recent onset AF in anticoagulant-naïve patients and to study related effects on cognitive function and biomarkers of cerebral damage, S100b. METHODS: Patients with AF duration > 48 hours were prospectively included. Brain magnetic resonance imaging (MRI) and S100b, were obtained prior, after and 7-10 days following CV. Trail making tests (TMT-A and TMT-B) and their difference, ΔΤΜΤ, were assessed prior to CV, 7-10 days and 30 days after CV. RESULTS: Forty-three patients (84% males) with median CHA2DS2-VASc score 1 (interquartile range 0-1) were included. Sequential MRI, including diffusion weighted scans, showed no new brain lesions after CV. Chronic white matter hyperintensities were present at baseline in 21/43 (49%) patients. The S100b (µg/l) levels increased significantly from baseline, (mean ±SD) 0.0472±0.0182 to 0.0551±0.0185 after CV, p=0.001 and then decreased 7-10 days after CV to 0.0450±0.0186, p <.;0.001. Consecutive TMT scores improved successively after CV, being statistically and clinically significant for TMT-B (p<0.01) and ΔΤΜΤ (p=0.005) between 7-10 days and 30 days after CV (Reliable Change Index >1.96). CONCLUSIONS: New brain lesions could not be detected on MRI after CV, but the high incidence of white matter hyperintensities and the transient increase in S100b may indicate transient or minor brain damage undetectable by MRI thus heightening the need to reevaluate thromboembolic risk prior to CV even in low risk patients.

Effect of Catheter Ablation vs Antiarrhythmic Medication on Quality of Life in Patients With Atrial Fibrillation: The CAPTAF Randomized Clinical Trial.

Importance: Quality of life is not a standard primary outcome in ablation trials, even though symptoms drive the indication. Objective: To assess quality of life with catheter ablation vs antiarrhythmic medication at 12 months in patients with atrial fibrillation. Design, Setting, and Participants: Randomized clinical trial at 4 university hospitals in Sweden and 1 in Finland of 155 patients aged 30-70 years with more than 6 months of atrial fibrillation and treatment failure with 1 antiarrhythmic drug or ß-blocker, with 4-year follow-up. Study dates were July 2008-September 2017. Major exclusions were ejection fraction <35%, left atrial diameter >60 mm, ventricular pacing dependency, and previous ablation. Interventions: Pulmonary vein isolation ablation (n = 79) or previously untested antiarrhythmic drugs (n = 76). Main Outcomes and Measures: Primary outcome was the General Health subscale score (Medical Outcomes Study 36-Item Short-Form Health Survey) at baseline and 12 months, assessed unblinded (range, 0 [worst] to 100 [best]). There were 26 secondary outcomes, including atrial fibrillation burden (% of time) from baseline to 12 months, measured by implantable cardiac monitors. The first 3 months were excluded from rhythm analysis. Results: Among 155 randomized patients (mean age, 56.1 years; 22.6% women), 97% completed the trial. Of 79 patients randomized to receive ablation, 75 underwent ablation, including 2 who crossed over to medication and 14 who underwent repeated ablation procedures. Of 76 patients randomized to receive antiarrhythmic medication, 74 received it, including 8 who crossed over to ablation and 43 for whom the first drug used failed. General Health score increased from 61.8 to 73.9 points in the ablation group vs 62.7 to 65.4 points in the medication group (between-group difference, 8.9 points; 95% CI, 3.1-14.7; P = .003). Of 26 secondary end points, 5 were analyzed; 2 were null and 2 were statistically significant, including decrease in atrial fibrillation burden (from 24.9% to 5.5% in the ablation group vs 23.3% to 11.5% in the medication group; difference -6.8% [95% CI, -12.9% to -0.7%]; P = .03). Of the Health Survey subscales, 5 of 7 improved significantly. Most common adverse events were urosepsis (5.1%) in the ablation group and atrial tachycardia (3.9%) in the medication group. Conclusions and Relevance: Among patients with symptomatic atrial fibrillation despite use of antiarrhythmic medication, the improvement in quality of life at 12 months was greater for those treated with catheter ablation compared with antiarrhythmic medication. Although the study was limited by absence of blinding, catheter ablation may offer an advantage for quality of life. Trial Registration: clinicaltrialsregister.eu Identifier: 2008-001384-11.

Cryoballoon vs. radiofrequency ablation for atrial fibrillation: a study of outcome and safety based on the ESC-EHRA atrial fibrillation ablation long-term registry and the Swedish catheter ablation registry.

AIMS: Pulmonary vein isolation (PVI), the standard for atrial fibrillation (AF) ablation, is most commonly applied with radiofrequency (RF) energy, although cryoballoon technology (CRYO) has gained widespread use. The aim was to compare the second-generation cryoballoon and the irrigated RF energy regarding outcomes and safety. METHODS AND RESULTS: Of 4657 patients undergoing their first AF ablation, 982 with CRYO and 3675 with RF energy were included from the Swedish catheter ablation registry and the Atrial Fibrillation Ablation Long-Term registry of the European Heart Rhythm Association of the European Society of Cardiology. The primary endpoint was repeat AF ablation. The major secondary endpoints included procedural duration, tachyarrhythmia recurrence, and complication rate. The re-ablation rate after 12 months was significantly lower in the CRYO vs. the RF group, 7.8% vs. 11%, P = 0.005, while freedom from arrhythmia recurrence (30 s duration) did not differ between the groups, 70.2 % vs. 68.2%, P = 0.44. The result was not influenced by AF type and lesion sets applied. In the Cox regression analysis, paroxysmal AF had significantly lower risk for re-ablation with CRYO, hazard ratio 0.56 (P = 0.041). Procedural duration was significantly shorter with CRYO than RF, (mean ± SD) 133.6 ± 45.2 min vs. 174.6 ± 58.2 min, P < 0.001. Complication rates were similar; 53/982 (5.4%) vs. 191/3675 (5.2%), CRYO vs. RF, P = 0.806. CONCLUSION: The lower re-ablation rates and shorter procedure times observed with the cryoballoon as compared to RF ablation may have important clinical implications when choosing AF ablation technique despite recognized limitations with registries.

Clinical outcome of the 2nd generation cryoballoon for pulmonary vein isolation in patients with persistent atrial fibrillation - A sub-study of the randomized trial evaluating single versus dual cryoballoon applications.

AIMS: To assess the efficacy of the 2nd generation Cryoballoon for pulmonary vein isolation (PVI) in patients with persistent atrial fibrillation (PersAF), and to compare it to patients with paroxysmal atrial fibrillation (PAF). METHODS: The outcome (arrhythmia recurrence at 12 months) was prospectively assessed in patients with PersAF(n = 77) and compared to that in patients with PAF(n = 62), who underwent PVI within a randomized trial evaluating single versus dual applications with the 2nd generation cryoballoon. Other endpoints included symptoms of AF, quality of life, procedure related characteristics, redo ablation rates and adverse events. Variables predicting recurrences were studied including all patients. RESULTS: Freedom from arrhythmia recurrence was 64.9% after a single ablation and 68.8% after one or more procedures, which was significantly lower compared to PAF patients; 82.2% (p = 0.029) and 83.9% (p = 0.048) respectively, at 12 months. The improvements in EHRA score (-1.3 ±â€¯0.8, p < 0.0001), symptom severity score (SSQ) (-5.0 ±â€¯4.2, p < 0.0001) and EQ5D-5 L global score (+10.4 ±â€¯20.3, p = 0.0002) after ablation was significant compared to baseline. The re-ablation rate was 7/77 (9.1%) which did not differ from that in PAF patients, 9/62 (14.5%), p = 0.42. Procedure duration, 104.8 ±â€¯37.4 versus 113 ±â€¯31.2 min (p = 0.129), application time, 1605 ±â€¯659 versus 1521 ±â€¯557 s (p = 0.103) and total adverse events after 12 months, 8/77 (10.4%) versus 5/62 (8.1%) (p = 0.77) did not differ in PersAF versus PAF patients. CONCLUSION: Both symptoms and QoL improved significantly in patients with PersAF after ablation. Freedom from AF was clinically significant but lower than in PAF patients. The cryoballoon seems an effective technique also in patients with persistent AF.

Acute and long-term efficacy and safety with a single cryoballoon application as compared with the standard dual application strategy: a prospective randomized study using the second-generation cryoballoon for pulmonary vein isolation in patients with symptomatic atrial fibrillation.

Aims: A single cryoballoon (CB) application per vein for pulmonary vein isolation (PVI) in patients with atrial fibrillation (AF) could save time and was therefore compared to the standard approach of two consecutive CB applications for acute and long-term efficacy and safety. Methods and results: Patients with symptomatic AF were randomized to a single CB application per vein guided by an Achieve® catheter (Single cryo-arm) or to two CB applications using a standard guidewire (Routine cryo-arm). The primary endpoint was the rate of acute complete PVI. Secondary endpoints were freedom from AF evaluated by electrocardiogram and 7 days Holter at 6 and 12 months, symptoms by Symptom Severity Questionnaires and EHRA score and quality of life (QoL) by EQ5D-5L at 12 months. Among 140 patients included, PVI was achieved in 271 (100%) veins in the Single cryo-arm and in 269/271 (99.3%) veins in the Routine cryo-arm, P = 0.25. The procedure time was shorter in the Single cryo-arm, mean ± standard deviation 99.4 ± 33.3 min vs. 118.4 ± 34.3 min, P = 0.0015. Freedom from AF after one procedure at 12 months did not differ; 73.9.0% (Single cryo) vs. 71.4% (Routine), P = 0.74. Symptoms and QoL did also not differ between the two groups. There was a lower complication rate in the Single cryo-group, 2.9% vs. 12.9%, P = 0.03. Conclusion: A single CB application shortens the procedure time without affecting acute or long-term efficacy, as compared to the routine two-application strategy, which with the lower complication rates has important implications when defining standards for PVI.

Supraventricular Arrhythmias in Patients with Adult Congenital Heart Disease.

An increasing number of patients with congenital heart disease survive to adulthood; such prolonged survival is related to a rapid evolution of successful surgical repairs and modern diagnostic techniques. Despite these improvements, corrective atrial incisions performed at surgery still lead to subsequent myocardial scarring harbouring a potential substrate for macro-reentrant atrial tachycardia. Macroreentrant atrial tachycardias are the most common (75 %) type of supraventricular tachycardia (SVT) in patients with adult congenital heart disease (ACHD). Patients with ACHD, atrial tachycardias and impaired ventricular function - important risk factors for sudden cardiac death (SCD) - have a 2-9 % SCD risk per decade. Moreover, ACHD imposes certain considerations when choosing antiarrhythmic drugs from a safety aspect and also when considering catheter ablation procedures related to the inherent cardiac anatomical barriers and required expertise. Expert recommendations for physicians managing these patients are therefore mandatory. This review summarises current evidence-based developments in the field, focusing on advances in and general recommendations for the management of ACHD, including the recently published recommendations on management of SVT by the European Heart Rhythm Association.

Thoracoscopic epicardial left atrial ablation in symptomatic patients with atrial fibrillation.

AIMS: The low efficacy rates reported for conventional catheter ablation of longstanding persistent atrial fibrillation (LPAF) have led to the development of alternative techniques such as minimal invasive surgical ablation, aiming for durable and contiguous transmural lesions. The aim was to evaluate the efficacy and safety of total thoracoscopic epicardial left atrial ablation (TELA-AF) procedures in a prospective study of severely symptomatic patients with either drug-resistant AF and/or failed attempts of catheter ablation. METHODS AND RESULTS: The TELA-AF surgical technique includes pulmonary vein isolation, left atrial (LA) 'box lesion', and partial vagal denervation. The LA appendage was excluded if deemed safe. Patients were followed with clinical evaluations and 12-lead electrocardiograms at 3, 6, and 12 months after the surgical intervention, complemented with a 7-day Holter monitoring after 6 and 12 months. Sixty patients, of whom 38 (63%) suffered from LPAF, underwent TELA-AF between November 2008 and December 2010. One patient with LPAF was lost to follow-up. At 12-month follow-up, 55/59 patients (93%) were free from atrial fibrillation (AF), while 7/59 patients (12%) suffered from recurrent LA tachycardia. Among patients with LPAF, 32/37 (86%) maintained sinus rhythm after 12 months. Adverse events included four perioperative bleedings requiring conversion to sternotomy in three cases, two ischaemic strokes and one transient ischaemic attack. CONCLUSION: The total thoracoscopic surgical ablation procedure is highly effective even in patients with LPAF, and it seems safe. The high rate of iatrogenic LA re-entrant tachycardia, however, warrants further improvement of the technique.

Executive Summary: European Heart Rhythm Association Consensus Document on the Management of Supraventricular Arrhythmias: Endorsed by Heart Rhythm Society (HRS), Asia-Pacific Heart Rhythm Society (APHRS), and Sociedad Latinoamericana de Estimulación Cardiaca y Electrofisiologia (SOLAECE).

This paper is an executive summary of the full European Heart Rhythm Association (EHRA) consensus document on the management of supraventricular arrhythmias, published in Europace. It summarises developments in the field and provides recommendations for patient management, with particular emphasis on new advances since the previous European Society of Cardiology guidelines. The EHRA consensus document is available to read in full at http://europace.oxfordjournals.org.

Ablation of atrial fibrillation with cryoballoon or duty-cycled radiofrequency pulmonary vein ablation catheter: a randomized controlled study comparing the clinical outcome and safety; the AF-COR study.

AIMS: The urge to facilitate the atrial fibrillation (AF) ablation procedure has led to the development of new ablation catheters specifically designed as 'one-shot tools' for pulmonary vein isolation (PVI). The purpose of this study was to compare the efficacy, safety, and procedure times for two such catheters using different energy sources. METHODS AND RESULTS: One hundred and ten patients, referred for ablation of paroxysmal or persistent AF, were randomized to treatment with either the cryoballoon or the circular multipolar duty-cycled radiofrequency-based pulmonary vein ablation catheter (PVAC). Complete PVI was achieved in 98 vs. 93% patients in the cryoballoon and PVAC group, respectively, with complication rates of 8 vs. 2% (P = 0.2). Complete freedom from AF, without antiarrhythmic drugs, after one single ablation procedure was seen in 46% in the cryoballoon vs. 34% after 12 months (P = 0.2). Procedure times were comparable, but fluoroscopy time was shorter for the cryoballoon (32 ± 16 min) than for the PVAC procedures (47 ± 17 min) (P < 0.001). A significant improvement of quality of life (QoL) and arrhythmia-related symptoms was seen in both groups after ablation. CONCLUSION: Both catheters proved comparably effective and safe in achieving acute PVI, apart from the shorter fluoroscopy times achieved with the cryoballoon. At follow-up, there was no statistically significant difference between the groups regarding freedom from AF and clinical success. The QoL increased to the same levels as for the general Swedish population in both groups.

Comparison of effects on coagulation and inflammatory markers using a duty-cycled bipolar and unipolar radiofrequency pulmonary vein ablation catheter vs. a cryoballoon catheter for pulmonary vein isolation.

AIMS: Thrombo-embolic events are one of the most feared complications related to atrial fibrillation (AF) ablation. Since radiofrequency (RF) energy is thought to be associated with a higher risk of thrombus formation than cryoenergy, the purpose of this study was to assess if the degree of activation of coagulation and inflammatory markers differed between ablation procedures performed with a cryoballoon catheter vs. a RF energy-based pulmonary vein ablation catheter (PVAC), respectively. METHODS AND RESULTS: Thirty patients referred for AF ablation were randomized to pulmonary vein isolation with either the cryoballoon or the PVAC. Biomarkers were studied for endothelial damage (von Willebrand factor antigen), platelet activation (soluble P-selectin), and coagulation activity [prothrombin fragment 1 + 2 (F1 + 2) and D-dimer] at five different time points during the procedure. Troponin I (Trop I) and C-reactive protein were analysed to reflect myocardial destruction and inflammatory activity. Markers of endothelial damage and platelet activation increased after ablation in both the cryo and the RF group. Similarly, the D-dimer levels increased significantly (P = 0.001) in both groups, whereas the F1 + 2 levels increased after the transseptal puncture only (P = 0.001). The overall activation of the coagulation system was, however, comparable between the groups. The cryoballoon was associated with higher Trop I compared with the PVAC (P < 0.001), but the ratios between biomarkers and Trop I were higher with the PVAC than with the cryoballoon. CONCLUSION: Even though the cryoballoon causes a higher degree of myocardial destruction than the PVAC, markers of coagulation, endothelial damage, and inflammation were comparable between the two techniques.

Right ventricular contractility as a measure of optimal interventricular pacing setting in cardiac resynchronization therapy.

AIMS: The aim of the present study was to assess whether right ventricular (RV) contractility can be used for optimization of the interventricular (VV) interval and to study the acute hemodynamic effect of different VV intervals on right and left ventricular (LV) contractility in patients referred for cardiac resynchronization therapy (CRT). METHODS AND RESULTS: Intracardiac LV and RV dP/dt were measured with a 0.014-in. sensor-tipped pressure guidewire during pacing at nine different VV intervals ranging from +80 ms (LV pre-excitation) to -80 ms (RV pre-excitation) in 26 patients who received a biventricular pacemaker. No correlation was found between the optimal VV intervals identified by maximum LV dP/dt and RV dP/dt, which were identical in only seven cases (27%). Only when testing slightly broader intervals (+/-20 ms) was there a statistically significant correlation (P= 0.037) between the optimized VV intervals. In the majority of patients (58%) either LV or RV pre-excitation was superior to simultaneous pacing according to LV dP/dt(max) measurements. CONCLUSION: RV dP/dt(max) failed to identify the optimal VV interval when compared with LV dP/dt(max) and can therefore not be recommended for VV optimization in CRT patients.

The use of impedance cardiography for optimizing the interventricular stimulation interval in cardiac resynchronization therapy-a comparison with left ventricular contractility.

The present study aimed to assess whether impedance cardiography (IC) can correctly identify the optimal interventricular (VV) pacing interval in cardiac resynchronization therapy (CRT). Twenty four patients received a biventricular pacemaker and underwent IC for cardiac output (CO) measurements to identify the optimal VV interval. Invasive measurements of left ventricular (LV) dP/dt(max) were used as a reference. During optimization the VV interval was changed with 20 ms steps from +80 (LV pre-excitation) to-80 ms (RV pre-excitation). The optimal VV interval was defined as the one that resulted in the highest LV dP/dt(max) value and the highest CO obtained by IC, respectively. During simultaneous biventricular pacing both LV dP/dt(max) and CO increased (mean 16.6% and 16.2%, respectively) as compared to baseline. Biventricular pacing with optimized VV intervals resulted in a further absolute increase of LV dP/dt (max) and CO (5.6% and 41.3%, respectively). The average decrease in LV dP/dt(max) was 79.6 +/- 51.6 mmHg/s when the optimal VV interval was programmed according to the IC measurements. Cross spectral analysis showed no correlation between the optimal VV intervals identified by the two methods (p > 0.05) and identical optimal VV intervals were identified in only six of the 24 patients. When broader VV time intervals were compared the correlation between the two methods was statistically significant (p = 0,0166). In conclusion, the use of IC for VV interval optimization is questionable since these optimized time intervals do not seem to correlate well with those obtained by measuring LV dP/dt.

A prospective randomised comparison of large-tip cryoablation and 8-mm-tip radiofrequency catheter ablation of atrial flutter.

PURPOSE: Although radiofrequency (RF) energy is routinely used for tricuspid isthmus (TI) ablation, it is often associated with discomfort. The paucity of studies comparing the feasibility and efficacy of cryo- versus RF energy for TI-ablation urged us to conduct a prospective, randomised trial. METHODS: Forty patients with atrial flutter (AFl) were randomised to RF- or cryoenergy for TI-ablation. Perceived pain was scored from 1 to 10 on a Visual Analogue Scale. RESULTS: Significantly lower pain scores were recorded for cryoablation versus RF ablation (0.96 +/- 0.73 versus 4.2 +/- 2.4, p = 0.00004). Cryoablation was associated with significantly longer procedure duration and ablation time (137 +/- 35 versus 111 +/- 29 min, p = 0.016 and 81 +/- 40 versus 48 +/- 30 min, p = 0.007) and lower acute success rate (56% versus 100%, p = 0.001) than RF ablation. The recurrence of AFl was 20% (cryo) versus 15% (RF; p = 0.45) after a mean of 15.1 months follow-up. CONCLUSION: Cryoablation results in significantly less pain and discomfort compared to RF ablation of AFl, which is offset by the significantly lower acute success rate.

Acute and clinical effects of cryoballoon pulmonary vein isolation in patients with symptomatic paroxysmal and persistent atrial fibrillation.

AIMS: To assess the acute effects, safety, and clinical outcome of atrial fibrillation (AF) ablation using a cryoballoon catheter. METHODS AND RESULTS: Forty patients with paroxysmal or persistent AF underwent pulmonary vein (PV) isolation with a cryoballoon catheter (Arctic Front, CryoCath). Electrocardiograms were recorded in case of symptomatic AF recurrences, and a 24 h Holter recording was performed at last follow-up. Complete PV isolation was achieved in 39 (91%) of the 43 procedures (56% with the cryoballoon catheter alone, 44% with an additional conventional ryocatheter). The number of balloon applications per procedure was 9.6 +/- 1.6. The PV isolation rate was significantly higher (83.9%) if total vessel occlusions were obtained than if intermediate (63.6%, P = 0.01) or poor occlusions were achieved (38.1%, P = 0.0002). The mean procedure time was 239 +/- 48 min. At follow-up (mean 8.9 +/- 4.6 months), 52.5% of patients were free from arrhythmia-related symptoms and another 17.5% had reduction of arrhythmia-related symptoms. Two cases each of phrenic nerve paralysis and dysphagia occurred. CONCLUSIONS: Cryoballoon PV isolation is a feasible technique with a high acute success rate and comparable clinical outcome to radiofrequency ablation. Although complications were rare, the need for an additional conventional cryocatheter warrants further development of the technique.