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Real-Time Contact Force Sensing for Pulmonary Vein Isolation in the Setting of Paroxysmal Atrial Fibrillation: Procedural and 1-Year Results

The additional benefit of contact force (CF) technology during pulmonary vein isolation (PVI) for paroxysmal atrial fibrillation (AF) to improve mid‐term clinical outcome is unclear.

Contact-force guided radiofrequency vs. second-generation balloon cryotherapy for pulmonary vein isolation in patients with paroxysmal atrial fibrillation—a prospective evaluation

AIMS In the setting of paroxysmal atrial fibrillation (AF), there are no available data comparing the mid-term outcome of patients undergoing pulmonary vein isolation (PVI) catheter ablation using contact-force (CF)-guided radiofrequency (RF) vs. second-generation balloon cryotherapy. METHODS AND RESULTS Prospective single-centre evaluation, carried out from March 2011 to February 2013, comparing CF radiofrequency (Thermocool(®) SmartTouch™, Biosense Webster, Inc.) (CF group) with cryoballoon ablation (Arctic Front Advance™ 28 mm cryoballoon, Medtronic, Inc.) (CB group), in regards to procedural safety and efficacy, as well as recurrence at 12 months. Overall, 150 consecutive patients were enrolled (75 in each group). The characteristics of patients of both the groups were similar (61.2 ± 9.9 years, women 25.3%, mean AF duration 4.1 ± 4.0 years, mean CHA2DS2-VASc score 1.4 ± 1.3, mean HAS-BLED 1.4 ± 0.6). Duration of the procedure was significantly lower in the CF group (110.7 ± 32.5 vs. 134.5 ± 48.3 min, P = 0.001), with a lower duration of fluoroscopy (21.5 ± 8.5 vs. 25.3 ± 9.9 min, P = 0.017) and X-ray exposure (4748 ± 2411 cGy cm² vs. 7734 ± 5361 cGy cm², P = 0.001). In contrast, no significant difference was found regarding significant procedural complication (2.7 vs. 1.3% in CF and CB groups, respectively; P = 0.56), and PVI was eventually achieved in all cases. At 12 months, AF recurrence occurred in 11 patients (14.7%) in the CB group and in 9 patients (12.0%) in the CF group (HR = 1.20 95% CI 0.50-2.90; log rank P = 0.682). CONCLUSIONS Our preliminary findings suggest that CF-guided radiofrequency and cryotherapy present very similar performances in the setting of paroxysmal AF catheter ablation.

Comparison between radiofrequency with contact force-sensing and second-generation cryoballoon for paroxysmal atrial fibrillation catheter ablation: a multicentre European evaluation

AIMS Whether pulmonary vein isolation (PVI) for paroxysmal atrial fibrillation (PAF) using contact force (CF)-guided radiofrequency (RF) or second-generation cryoballoon (CB) present similar efficacy and safety remains uncertain. METHODS AND RESULTS We performed a multicentre study comparing procedural safety and arrhythmia recurrence after standardized PVI catheter ablation for PAF using CF-guided RF ablation (Thermocool(®) SmartTouch™, Biosense Webster; or Tacticath™, St Jude Medical) (CF group) with second-generation CB ablation (Arctic Front Advance™, Medtronic) (CB group). Overall, 376 patients (mean age 59.8 ± 10.4 years, 280 males) were enrolled in 4 centres: 198 in CF group and 178 in CB group. Procedure was shorter for CB group than for CF group (109.6 ± 40 vs. 122.5 ± 40.7 min, P = 0.003), but fluoroscopy duration and X-ray exposure were not statistically different (P = 0.1 and P = 0.22, respectively). Overall complication rate was similar in both groups: 14 (7.1%) in the CF group vs. 13 (7.3%) in the CB group (P = 0.93). However, transient right phrenic nerve palsy occurred only in CB group (10 patients, 5.6%; P = 0.001 vs. CF group) and severe non-lethal complications (embolic event, tamponade, or oesophageal injury) occurred only in CF group (5 patients, 2.5%; P = 0.03 vs. CB group). No periprocedural death occurred in either group. Single-procedure freedom from any atrial arrhythmias at 18 months post-ablation was comparable in CF group and CB group (76 vs. 73.3%, respectively, log rank P = 0.63). CONCLUSION Pulmonary vein isolation using CF-guided RF and second-generation CB leads to comparable single-procedure arrhythmia-free survival at up to 18 months with similar overall complication rate.

Safety and efficacy of dabigatran versus warfarin in patients undergoing catheter ablation of atrial fibrillation: a systematic review and meta-analysis

Background Dabigatran etexilate, a new thrombin inhibitor, has been shown to be comparable to warfarin in patients with atrial fibrillation (AF). However, there is a limited body of evidence on the efficacy and safety of using dabigatran among patients undergoing AF catheter ablation. Objective A random effects meta-analysis was performed of controlled trials comparing dabigatran and warfarin in paroxysmal/persistent AF patients undergoing catheter ablation. Methods Data sources included Medline, Embase, and Cochrane (from inception to April 2013). Three independent reviewers selected studies comparing warfarin to dabigatran. Descriptive and quantitative information was extracted from each selected study, regarding periprocedural all cause mortality, thromboembolic events and major bleeding, as well as modalities of periprocedural anticoagulation bridging. Results After a detailed screening of 228 search results, 14 studies were identified enrolling a total of 4782 patients (1823 treated with dabigatran and 2959 with warfarin). No deaths were reported. No significant differences were found between patients treated with dabigatran and warfarin as regards thromboembolic events (0.55% dabigatran vs 0.17% warfarin; risk ratios (RR)=1.78, 95% CI 0.66 to 4.80; p=0.26) and major bleeding (1.48% dabigatran vs 1.35% warfarin; RR=1.07, 95% CI 0.51 to 2.26; p=0.86). No difference was found between the 110 mg twice daily and 150 mg twice daily dabigatran dosages concerning major bleeding (0% vs 1.62%, respectively; RR=0.19, 95% CI 0.01 to 3.18; p=0.25) and thromboembolism (0% vs 0.40%, respectively; RR=0.72, 95% CI 0.04 to 12.98; p=0.82). Conclusions In the specific setting of AF catheter ablation, this first pooled analysis suggests that patients treated with dabigatran have a similar incidence of thromboembolic events and major bleeding compared to warfarin, with low event rates overall.

Rivaroxaban and dabigatran in patients undergoing catheter ablation of atrial fibrillation

AIMS The recent availability of the novel oral anticoagulants (NOACs) may have led to a change in the anticoagulation regimens of patients referred to catheter ablation of atrial fibrillation (AF). Preliminary data exist concerning dabigatran, but information regarding the safety and efficacy of rivaroxaban in this setting is currently scarce. METHODS AND RESULTS Of the 556 consecutive eligible patients (age 61.0 ± 9.6; 74.6% men; 61.2% paroxysmal AF) undergoing AF catheter ablation in our centre (October 2012 to September 2013) and enroled in a systematic standardized 30-day follow-up period: 192 patients were under vitamin K antagonists (VKAs), 188 under rivaroxaban, and 176 under dabigatran. Peri-procedural mortality and significant systemic or pulmonary thromboembolism (efficacy outcome), as well as bleeding events (safety outcome) during the 30 days following the ablation were evaluated according to anticoagulation regimen. During a 12-month time interval, the use of the NOACs in this population rose from <10 to 70%. Overall, the rate of events was low with no significant differences regarding: thrombo-embolic events in 1.3% (VKA 2.1%; rivaroxaban 1.1%; dabigatran 0.6%; P = 0.410); major bleeding in 2.3% (VKA 4.2%; rivaroxaban 1.6%; dabigatran 1.1%; P = 0.112), and minor bleeding 1.4% (VKA 2.1%; rivaroxaban 1.6%; dabigatran 0.6%; P = 0.464). No fatal events were observed. CONCLUSION The use of the NOAC in patients undergoing catheter ablation of AF has rapidly evolved (seven-fold) over 1 year. These preliminary data suggest that rivaroxaban and dabigatran in the setting of catheter ablation of AF are efficient and safe, compared with the traditional VKA.

Possible refinement of clinical thromboembolism assessment in patients with atrial fibrillation using echocardiographic parameters

AIM Some transoesophageal echocardiogram (TEE) findings are associated with an increased risk of stroke in patients with atrial fibrillation (AF). This study was designed to evaluate and compare the accuracy of CHADS(2) and CHA(2)DS(2)-VASc in the prediction of these findings and test the additive value of transthoracic echocardiogram (TTE)-derived parameters as a possible refinement for these classifications. METHODS AND RESULTS Cross-sectional study of 405 consecutive patients who underwent TTE and TEE evaluation during AF. Stroke risk assessment was performed using the CHADS(2) and CHA(2)DS(2)-VASc scores, alone and alongside with the addition of two TTE-derived parameters (left atrium area and left ventricle global systolic function). Comparisons regarding the presence of left atrial appendage thrombi (LAA T), dense spontaneous echo contrast (SEC), and left atrial appendage (LAA) low flow velocities (LFV) were performed using receiver operating characteristic curves. In low-risk patients, as assessed through the CHA(2)DS(2)-VASc score and CHADS(2) and CHA(2)DS(2)-VASc scores plus echo parameters, no high-risk features were found on TEE. In subjects classified as low risk using CHADS(2), this figure rose to 10%. No significant differences were found between CHADS(2) and CHA(2)DS(2)-VASc in the prediction of LAA T, dense SEC, and LAA LFV. The addition of TTE-derived parameters to the previous clinical-risk scores resulted in improved prediction of the TEE endpoints. CONCLUSION These findings suggest that the use of TTE-derived parameters may be a valuable way of refining the available clinical risk schemes for the detection of surrogate markers of stroke. Follow-up studies using clinical endpoints will be necessary to confirm this hypothesis.

Is There Still a Role for Complex Fractionated Atrial Electrogram Ablation in Addition to Pulmonary Vein Isolation in Patients With Paroxysmal and Persistent Atrial Fibrillation? Meta-Analysis of 1415 Patients.

Background—Ablation of complex fractionated atrial electrograms (CFAEs) has been proposed as a strategy to improve outcomes in atrial fibrillation (AF) catheter ablation, but the use of this technique remains contentious. We aimed to assess the impact of CFAE ablation in addition to pulmonary vein isolation (PVI) in patients undergoing ablation for AF. Methods and Results—We performed a random effects meta-analysis of studies comparing PVI versus PVI+CFAE ablation. The outcomes of freedom from AF/atrial tachycardia after 1 or several ablation procedures and acute procedural–related complications were assessed. Studies were searched on MEDLINE, EMBASE, COCHRANE, and clinicaltrials.gov, and sensitivity analyses were performed. Thirteen studies including a total of 1415 patients were considered eligible. Additional ablation of CFAEs resulted in no improvement in mid-term procedural outcome or freedom from AF or atrial tachycardia (odds ratio [OR], 0.80; 95% confidence interval [CI], 0.58–1.10; P=0.17). Sensitivity analysis of 398 paroxysmal AF ablation procedures showed no incremental benefit of CFAE ablation (OR, 0.80; 95% CI, 0.46–1.38; P=0.42). PVI+CFAE ablation versus PVI alone did not improve the overall rate of freedom from AF or atrial tachycardia in patients with persistent AF (OR, 1.01; 95% CI, 0.63–1.64; P=0.96) or longstanding persistent AF (OR, 0.84; 95% CI, 0.24–2.96; P=0.79). There was no increase in procedural-related adverse events (OR, 1.06; 95% CI, 0.41–2.75; P=0.91). Conclusions—Despite the apparent safety of this technique, CFAE ablation did not improve freedom from AF/atrial tachycardia in patients with paroxysmal or persistent AF. The role of CFAE ablation in addition to PVI should be questioned and other alternatives assessed to improve the outcome of AF ablation.

Is There Still a Role for CFAE Ablation in Addition to Pulmonary Vein Isolation in Patients with Paroxysmal and Persistent Atrial Fibrillation? A Meta-Analysis of 1,415 Patients

Background—Ablation of complex fractionated atrial electrograms (CFAEs) has been proposed as a strategy to improve outcomes in atrial fibrillation (AF) catheter ablation, but the use of this technique remains contentious. We aimed to assess the impact of CFAE ablation in addition to pulmonary vein isolation (PVI) in patients undergoing ablation for AF. Methods and Results—We performed a random effects meta-analysis of studies comparing PVI versus PVI+CFAE ablation. The outcomes of freedom from AF/atrial tachycardia after 1 or several ablation procedures and acute procedural–related complications were assessed. Studies were searched on MEDLINE, EMBASE, COCHRANE, and clinicaltrials.gov, and sensitivity analyses were performed. Thirteen studies including a total of 1415 patients were considered eligible. Additional ablation of CFAEs resulted in no improvement in mid-term procedural outcome or freedom from AF or atrial tachycardia (odds ratio [OR], 0.80; 95% confidence interval [CI], 0.58–1.10; P=0.17). Sensitivity analysis of 398 paroxysmal AF ablation procedures showed no incremental benefit of CFAE ablation (OR, 0.80; 95% CI, 0.46–1.38; P=0.42). PVI+CFAE ablation versus PVI alone did not improve the overall rate of freedom from AF or atrial tachycardia in patients with persistent AF (OR, 1.01; 95% CI, 0.63–1.64; P=0.96) or longstanding persistent AF (OR, 0.84; 95% CI, 0.24–2.96; P=0.79). There was no increase in procedural-related adverse events (OR, 1.06; 95% CI, 0.41–2.75; P=0.91). Conclusions—Despite the apparent safety of this technique, CFAE ablation did not improve freedom from AF/atrial tachycardia in patients with paroxysmal or persistent AF. The role of CFAE ablation in addition to PVI should be questioned and other alternatives assessed to improve the outcome of AF ablation.

Implantable cardioverter-defibrillators in the elderly: rationale and specific age-related considerations

Despite the increasingly high rate of implantation of cardioverter-defibrillators (ICD) in elderly patients, data supporting their clinical and cost-effectiveness in this age stratum are ambiguous and contradictory. We comprehensively reviewed the state-of-the-art data regarding the applicability, safety, clinical- and cost-effectiveness of the ICD in elderly patients, and analysed which patients in this age stratum are more likely to get a survival benefit from this therapy. Although peri-procedural risk may be slightly higher in the elderly, this procedure is still relatively safe in this age group. In terms of correcting potentially life-threatening arrhythmias, the effectiveness of ICD therapy is comparable in older and younger individuals. However, the assumption of persistent ICD benefit in the elderly population is questionable, as any advantage of the device on arrhythmic death may be largely attenuated by a higher total non-arrhythmic mortality. While septuagenarians and octogenarians have higher annual all-cause mortality rates, ICD therapy may remain effective in highly selected patients at high risk of arrhythmic death and with minimum comorbidities despite advanced age. ICD intervention among the elderly, as a group, may not be cost-effective, but the procedure may reach cost-effectiveness in those expected to live >5-7 years after implantation. Biological age rather than chronological age per se should be the decisive factor in making a decision on ICD selection for survival benefit.

Cardiac troponin I: Prothrombotic risk marker in non-valvular atrial fibrillation

BACKGROUND Evidence of a link between small rises in cardiac troponin I (cTnI) and an increased risk of thromboembolic events (TE) in atrial fibrillation (AF) is currently scarce. OBJECTIVES We aimed to assess the relation between cTnI and findings of an increased thromboembolic risk in patients with non-valvular AF using transesophageal echocardiography. METHODS We have included 245 patients performing transthoracic and transesophageal echocardiogram, alongside with laboratory assessment (including cTnI) in a cross-sectional survey. Changes associated to TE were sought on transesophageal echocardiogram: left atrial or left atrial appendage thrombus, dense spontaneous echocardiographic contrast, low flow velocities in the left atrial appendage and protuberant aortic plaques. Comparisons were performed according to the baseline concentration of cTnI, regarding the prevalence of these changes. We have added cTnI to CHADS2 and CHA2DS2-VASc scores in order to assess its capability to refine risk stratification using transesophageal markers as surrogate endpoints and assessed it by means of ROC-curve analysis and Net Reclassification Improvement (NRI). RESULTS A direct relation between rising concentrations of cTnI and a higher prevalence of transesophageal echocardiogram changes was found. Furthermore, the addition of cTnI to CHADS2 and CHA2DS2-VASc scores improved their ability to predict changes associated to TE on transesophageal echocardiography both through ROC-curve analysis and NRI. CONCLUSION cTnI seems to be associated to thromboembolic risk in patients with AF. The possible role of cTnI in the refinement of risk stratification schemes needs to be tested in further prospective studies using clinical endpoints.