Pacemaker Implantation After Mitral Valve Surgery With Atrial Fibrillation Ablation

BackgroundThe incidence of permanent pacemaker (PPM) implantation is higher following mitral valve surgery (MVS) with ablation for atrial fibrillation (AF) compared with MVS alone.ObjectivesThis study identified risk factors and outcomes associated with PPM implantation in a randomized trial that evaluated ablation for AF in patients who underwent MVS.MethodsA total of 243 patients with AF and without previous PPM placement were randomly assigned to MVS alone (n = 117) or MVS + ablation (n = 126). Patients in the ablation group were further randomized to pulmonary vein isolation (PVI) (n = 62) or the biatrial maze procedure (n = 64). Using competing risk models, this study examined the association among PPM and baseline and operative risk factors, and the effect of PPM on time to discharge, readmissions, and 1-year mortality.ResultsThirty-five patients received a PPM within the first year (14.4%), 29 (83%) underwent implantation during the index hospitalization. The frequency of PPM implantation was 7.7% in patients randomized to MVS alone, 16.1% in MVS + PVI, and 25% in MVS + biatrial maze. The indications for PPM were similar among patients who underwent MVS with and without ablation. Ablation, multivalve surgery, and New York Heart Association functional (NYHA) functional class III/IV were independent risk factors for PPM implantation. Length of stay post-surgery was longer in patients who received PPMs, but it was not significant when adjusted for randomization assignment (MVS vs. ablation) and age (hazard ratio [HR]: 0.81; 95% confidence interval [CI]: 0.61 to 1.08; p = 0.14). PPM implantation did not increase 30-day readmission rate (HR: 1.43; 95% CI: 0.50 to 4.05; p = 0.50). The need for PPM was associated with a higher risk of 1-year mortality (HR: 3.21; 95% CI: 1.01 to 10.17; p = 0.05) after adjustment for randomization assignment, age, and NYHA functional class.ConclusionsAF ablation, multivalve surgery, and NYHA functional class III/IV were associated with an increased risk for permanent pacing. PPM implantation following MVS was associated with a significant increase in 1-year mortality. (Surgical Ablation Versus No Surgical Ablation for Patients With Atrial Fibrillation Undergoing Mitral Valve Surgery; NCT00903370)     

Left Atrial Late Gadolinium Enhancement is Associated With Incident Atrial Fibrillation as Detected by Continuous Monitoring With Implantable Loop Recorders

ObjectivesThe authors hypothesized that left atrial (LA) fibrosis was associated with incident atrial fibrillation (AF) as detected by continuous long-term monitoring in an at-risk population.BackgroundLA late gadolinium enhancement (LGE) measured with cardiac magnetic resonance is emerging as a marker of atrial fibrosis and has been associated with worse outcomes in AF ablation procedures; however, the prognostic value of LA LGE for incident AF remains unknown.MethodsCardiac magnetic resonance, including measurement of left ventricular and LA volumes and function, as well as left ventricular extracellular volume fraction and LA LGE, was acquired in 68 patients aged at least 70 years with risk factors for stroke. All included patients received an implantable loop recorder and were continuously monitored for previously unknown AF. Incident AF was adjudicated by senior cardiologists.ResultsPatients were monitored for AF with an implantable loop recorder during a median of 41 (interquartile range: 7) months. AF episodes lasting ≥6 min were detected in 32 patients (47%), and 16 patients (24%) experienced AF episodes lasting ≥5.5 h. In Cox regression analyses adjusted for sex, age, and comorbidities, we found that LA volumes and function and LA LGE were independently associated with incident AF. For LA LGE, the hazard ratios for time to AF episodes lasting ≥6 min and ≥5.5 h were 1.40 (95% CI: 1.03 to 1.89) per 10 cm² increase (p = 0.03) and 1.63 (95% CI: 1.11 to 2.40) per 10 cm² increase (p = 0.01), respectively. LA LGE was significantly associated with high burden of AF. The addition of LA LGE to a multivariable risk prediction model for incident AF significantly increased the predictive value.ConclusionsExtent of LA fibrosis measured by LA LGE was significantly associated with incident AF detected by implantable loop recorder. (Atrial Fibrillation Detected by Continuous ECG Monitoring [LOOP]; NCT02036450)     

Initial Findings From the National Cardiovascular Data Registry of Atrial Fibrillation Ablation Procedures

BackgroundThe National Cardiovascular Data Registry (NCDR) AFib Ablation Registry was created to assess real-world prevalence, demographic characteristics, procedural management, and outcomes of patients undergoing atrial fibrillation (AF) ablation procedures.ObjectivesThe goal of this study was to characterize the patient, hospital, and physician characteristics and in-hospital outcomes related to AF ablation in the first 5 years of the registry.MethodsThis paper describes the AFib Ablation Registry structure and governance, outcome assessment processes, data quality, and data collection processes. The characteristics of the patient population, hospitals, and in-hospital outcomes are also described.ResultsA total of 76,219 patients were included in the registry between January 2016 and December 2020 (mean age 65.5 ± 10.3 years, 65.2% male, 55.8% paroxysmal AF, mean CHA₂DS₂-VASc score 2.7 ± 1.6) treated by 708 physicians in 162 hospitals. Successful isolation of all pulmonary veins was achieved in 92.4% of patients. The prevalence of any complication during procedural admission was 2.50% and major complication was 0.9%, including significant bradycardia in 0.47%, heart failure in 0.47%, and pericardial effusion requiring intervention in 0.44%. Hospitalization >1 day occurred in 11.8% of patients, and in-hospital death was rare (n = 41 [0.05%]).ConclusionsThe NCDR AFib Ablation Registry is the largest multicenter, prospective cohort study of patients undergoing catheter ablation worldwide. Results in the first 5 years showed that successful pulmonary vein isolation is achieved in the majority of patients, with a low rate of complications. Future studies from the registry will assess practice trends, evaluate treatment patterns associated with different patient outcomes, and support development of evidence-based guidelines.     

Prevalence of Left Atrial Thrombus in Anticoagulated Patients With Atrial Fibrillation

BackgroundThe prevalence of left atrial (LA) thrombus in patients with atrial fibrillation (AF) or atrial flutter (AFL) on guideline-directed anticoagulation is not well known, yet this may inform transesophageal echocardiogram (TEE) use before cardioversion or catheter ablation.ObjectivesThe purpose of this study was to quantify LA thrombus prevalence among patients with AF/AFL on guideline-directed anticoagulation and to identify high-risk subgroups.MethodsEMBASE, MEDLINE, and CENTRAL were systematically searched from inception to July 2020 for studies reporting on LA thrombus prevalence among patients with AF/AFL undergoing TEE following at least 3 weeks of continuous therapeutic oral anticoagulation with vitamin K antagonists (VKAs) or direct oral anticoagulants (DOACs). Meta-analysis was performed using random effects models.ResultsThirty-five studies describing 14,653 patients were identified. The mean-weighted LA thrombus prevalence was 2.73% (95% confidence interval [CI]: 1.95% to 3.80%). LA thrombus prevalence was similar for VKA- and DOAC-treated patients (2.80%; 95% CI: 1.86% to 4.21% vs. 3.12%; 95% CI: 1.92% to 5.03%; p = 0.674). Patients with nonparoxysmal AF/AFL had a 4-fold higher LA thrombus prevalence compared with paroxysmal patients (4.81%; 95% CI: 3.35% to 6.86% vs. 1.03%; 95% CI: 0.52% to 2.03%; p < 0.001). LA thrombus prevalence was higher among patients undergoing cardioversion versus ablation (5.55%; 95% CI: 3.15% to 9.58% vs. 1.65%; 95% CI: 1.07% to 2.53%; p < 0.001). Patients with CHA₂DS₂-VASc scores ≥3 had a higher LA thrombus prevalence compared with patients with scores ≤2 (6.31%; 95% CI: 3.72% to 10.49% vs. 1.06%; 95% CI: 0.45% to 2.49%; p < 0.001).ConclusionsLA thrombus prevalence is high in subgroups of anticoagulated patients with AF/AFL, who may benefit from routine pre-procedural TEE use before cardioversion or catheter ablation.     

Structural Cardiac Remodeling in Atrial Fibrillation

ObjectivesThis study sought to evaluate preablation computed tomography angiography (CTA) for atrial and epicardial features to predict atrial fibrillation (AF) recurrence after ablation.BackgroundStructural atrial remodeling is a process associated with occurrence or persistence of AF. Different anatomical imaging features have been proposed to influence atrial remodeling both negatively and positively as substrate for AF.MethodsPatients with nonvalvular AF underwent cardiac CTA before pulmonary vein isolation at 2 high-volume centers. Left atrial (LA) and right atrial volumes, LA wall thickness (LAWT), and epicardial adipose tissue volume and attenuation were evaluated. Additional subanalyses of electroanatomical maps were made. Follow-up was performed for at least 12 months, including subanalysis of repeated cardiac CTA studies. Interrater variability was assessed.ResultsOf 732 patients, 270 (36.9%) had AF recurrence after a mean of 7 months. CT analysis revealed larger indexed LA volume (47.3 mL/m² vs 43.6 mL/m²; P = 0.0001) and higher mean anterior (1.91 mm vs 1.65 mm; P < 0.0001) and posterior (1.61 mm vs 1.39 mm; P = 0.001) LAWT in patients with AF recurrence. Epicardial adipose tissue volume in patients with AF recurrence was higher (144.5 mm³ vs 128.5 mm³; P < 0.0001) and further progressed significantly in a subset of 85 patients after 2 years (+11.8 mm² vs −3.5 mm²; P = 0.041). Attenuation levels were lower, indicating a higher lipid component associated with AF recurrence (−69.1 HU vs −67.5 HU; P = 0.001). A total of 103 atrial voltage maps were highly predictive of AF recurrence and showed good discriminatory power for patients with low voltage >50% and LAWT (1.55 ± 0.5 mm vs 1.81 ± 0.6 mm; P = 0.032). Net reclassification improvement (NRI) showed a significant incremental benefit (NRI = 0.279; P < 0.0001) when adding LAWT to established risk models.ConclusionsAtrial wall thickness, epicardial fat volume, and attenuation are associated with AF recurrence in patients undergoing ablation therapy.     

Mobile Health Technology to Improve Care for Patients With Atrial Fibrillation

BackgroundCurrent management of patients with atrial fibrillation (AF) is limited by low detection of AF, non-adherence to guidelines, and lack of consideration of patients’ preferences, thus highlighting the need for a more holistic and integrated approach to AF management.ObjectiveThe objective of this study was to determine whether a mobile health (mHealth) technology-supported AF integrated management strategy would reduce AF-related adverse events, compared with usual care.MethodsThis is a cluster randomized trial of patients with AF older than 18 years of age who were enrolled in 40 cities in China. Recruitment began on June 1, 2018 and follow-up ended on August 16, 2019. Patients with AF were randomized to receive usual care, or integrated care based on a mobile AF Application (mAFA) incorporating the ABC (Atrial Fibrillation Better Care) Pathway: A, Avoid stroke; B, Better symptom management; and C, Cardiovascular and other comorbidity risk reduction. The primary composite outcome was a composite of stroke/thromboembolism, all-cause death, and rehospitalization. Rehospitalization alone was a secondary outcome. Cardiovascular events were assessed using Cox proportional hazard modeling after adjusting for baseline risk.ResultsThere were 1,646 patients allocated to mAFA intervention (mean age, 67.0 years; 38.0% female) with mean follow-up of 262 days, whereas 1,678 patients were allocated to usual care (mean age, 70.0 years; 38.0% female) with mean follow-up of 291 days. Rates of the composite outcome of ‘ischemic stroke/systemic thromboembolism, death, and rehospitalization’ were lower with the mAFA intervention compared with usual care (1.9% vs. 6.0%; hazard ratio [HR]: 0.39; 95% confidence interval [CI]: 0.22 to 0.67; p < 0.001). Rates of rehospitalization were lower with the mAFA intervention (1.2% vs. 4.5%; HR: 0.32; 95% CI: 0.17 to 0.60; p < 0.001). Subgroup analyses by sex, age, AF type, risk score, and comorbidities demonstrated consistently lower HRs for the composite outcome for patients receiving the mAFA intervention compared with usual care (all p < 0.05).ConclusionsAn integrated care approach to holistic AF care, supported by mHealth technology, reduces the risks of rehospitalization and clinical adverse events. (Mobile Health [mHealth] technology integrating atrial fibrillation screening and ABC management approach trial; ChiCTR-OOC-17014138).     

Impact of Pre-Existing and New-Onset Atrial Fibrillation on Outcomes After Transcatheter Aortic Valve Replacement

ObjectivesThis study sought to evaluate impact of new-onset and pre-existing atrial fibrillation (AF) on transcatheter aortic valve replacement (TAVR) long-term outcomes compared with patients without AF.BackgroundPre-existing and new-onset AF in patients undergoing TAVR are associated with poor outcomes.MethodsThe study identified 72,660 patients ≥65 years of age who underwent nonapical TAVR between 2014 and 2016 using Medicare inpatient claims. History of AF was defined by diagnoses on claims during the 3 years preceding the TAVR, and new-onset AF was defined as occurrence of AF during the TAVR admission or within 30 days after TAVR in a patient without prior history of AF. Outcomes included all-cause mortality, and readmission for bleeding, stroke, and heart failure (HF).ResultsOverall, 40.7% had pre-existing AF (n = 29,563) and 6.8% experienced new-onset AF (n = 2,948) after TAVR. Mean age was 81.3, 82.4, and 83.8 years in patients with no AF, pre-existing, and new-onset AF, respectively. Pre-existing AF patients had the highest burden of comorbidities. After follow-up of 73,732 person-years, mortality was higher with new-onset AF compared with pre-existing and no AF (29.7, 22.6, and 12.8 per 100 person-years, respectively; p < 0.001). After adjusting for patient characteristics and hospital TAVR volume, new-onset AF remained associated with higher mortality compared with no AF (adjusted hazard ratio: 2.068, 95% confidence interval [CI]: 1.92 to 2.20; p < 0.01) and pre-existing AF (adjusted hazard ratio: 1.35; 95% CI: 1.26 to 1.45; p < 0.01). In competing risk analysis, new-onset AF was associated with higher risk of bleeding (subdistribution hazard ratio [sHR]: 1.66; 95% CI: 1.48 to 1.86; p < 0.01), stroke (sHR: 1.92; 95% CI: 1.63 to 2.26; p < 0.01), and HF (sHR: 1.98; 95% CI: 1.81 to 2.16; p < 0.01) compared with pre-existing AF.ConclusionsIn patients undergoing TAVR, new-onset AF is associated with increased risk of mortality and bleeding, stroke, and HF hospitalizations compared with pre-existing AF or no AF.     

El tejido adiposo epicárdico no es un predictor independiente de recurrencia de fibrilación auricular tras ablación con catéter

Introduction and objectivesPrevious studies have suggested that epicardial adipose tissue (EAT) could exert a paracrine effect in the myocardium. However, few studies have assessed its role in the risk of atrial fibrillation (AF) recurrence. This study aimed to evaluate the association between EAT volume, and its attenuation, with the risk of AF recurrence after AF ablation.MethodsA total of 350 consecutive patients who underwent AF ablation were included. The median age was 57 [IQR 48-65] years and 21% had persistent AF. Epicardial fat was quantified by multidetector computed tomography using Syngo.via Frontier-Cardiac Risk Assessment software, measuring pericardial fat volume (PATV), EAT volume, and attenuation of EAT posterior to the left atrium. AF recurrence was defined as any documented episode of AF, atrial flutter, or atrial tachycardia more than 3 months after the procedure.ResultsAfter a median follow-up of 34 [range, 12-57] months, 114 patients (33%) had AF recurrence. Univariable Cox regression showed that patients with an EAT volume ≥ 80 mL had an increased risk of AF recurrence (HR, 1.65; 95%CI, 1.14-2.39; P = .007). However, after multivariable adjustment, EAT volume did not remain an independent predictor of AF recurrence (HR, 1.24; 95%CI, 0.83-1.87; P = .3). Similar results were observed with PATV. Patients with lower attenuation of EAT did not have a higher risk of AF recurrence (log-rank test, P = .75).ConclusionsEAT parameters including the evaluation of EAT volume, PATV and EAT attenuation were not independent predictors of AF recurrence after catheter ablation.     

Valvular and Nonvalvular Atrial Fibrillation in Patients Undergoing Transcatheter Aortic Valve Replacement

ObjectivesThe aim of this study was to investigate the impact of valvular and nonvalvular atrial fibrillation (AF) in patients undergoing transcatheter aortic valve replacement (TAVR).BackgroundAF has been associated with adverse clinical outcomes after TAVR. However, the differential impact of valvular as opposed to nonvalvular AF has not been investigated.MethodsIn a retrospective analysis of a prospective registry, valvular AF was defined as AF in the setting of concomitant mitral stenosis or the presence of a mitral valve prosthesis. The presence of mitral stenosis was determined by pre-procedural echocardiography. The primary endpoint was a composite of cardiovascular death or disabling stroke at 1 year after TAVR.ResultsAmong 1,472 patients undergoing TAVR between August 2007 and June 2018, AF was recorded in 465 patients (31.6%) and categorized as nonvalvular in 376 (25.5%) and valvular in 89 (6.0%). AF scores including HAS-BLED, CHADS₂, and CHA₂DS₂-VASc were comparable between patients with nonvalvular and valvular AF. The primary endpoint occurred in 9.3% of patients with no AF, in 14.5% of patients with nonvalvular AF (hazard ratio: 1.57; 95% confidence interval: 1.12 to 2.20; p = 0.009), and in 24.2% of patients with valvular AF (hazard ratio: 2.75; 95% confidence interval: 1.71 to 4.41; p < 0.001). Valvular AF conferred an increased risk for cardiovascular death or disabling stroke compared with nonvalvular AF (hazard ratio: 1.77; 95% confidence interval: 1.07 to 2.94; p = 0.027).ConclusionsThe presence of valvular AF in patients undergoing TAVR increased the risk for cardiovascular death or disabling stroke compared with both no AF and nonvalvular AF. (SWISS TAVI Registry; NCT01368250)     

The impact of malnutrition on atrial fibrillation recurrence post ablation

Background and aimsBoth malnutrition and atrial fibrillation (AF) are the major health problems in modern society. Only a few studies focused on the relationship between malnutrition and recurrence of atrial arrhythmias post AF ablation (AF recurrence), which used body mass index (BMI) as nutrition assessment tool. However, BMI can't credibly reflect body composition and has limitation in patients with water-sodium retention. In this study, we used controlling nutritional status score (CONUT score) and geriatric nutritional risk index (GNRI) to identify the malnutrition patients and explored the effect of malnutrition on AF recurrence.Methods and resultsThis retrospective study included 246 patients who underwent AF ablation. During a median 11-month follow-up, 77 patients (31.3%) experienced AF recurrence. The recurrence group had higher CONUT score (2.3 ± 1.5 vs. 0.9 ± 1.0, P < 0.001) and lower GNRI (99.9 ± 7.6 vs. 103.9 ± 5.6, P < 0.001). After balancing the traditional risk factors, both CONUT score (OR: 2.614, 95%CI: 1.831–3.731, P < 0.001) and GNRI (OR: 0.884, 95%CI: 0.828–0.944, P < 0.001) were the independent predictors for AF recurrence. Pre-ablation CONUT score ≥1 and GNRI≥95.66 are indicative of AF recurrence. Adding CONUT score or GNRI to the base prediction model for AF recurrence significantly improved the discrimination and calibration. However, adding BMI to the base prediction model did not improve the model performance.ConclusionsCONUT score and GNRI are ideal tools to evaluate the nutrition status of AF patients. Undernourished patients are more likely to suffer from AF recurrence. Improving nutrition status may be a potential target for reducing the postoperative recurrence rate.     

Left Atrial Appendage Closure Versus Direct Oral Anticoagulants in High-Risk Patients With Atrial Fibrillation

BackgroundPercutaneous left atrial appendage closure (LAAC) is noninferior to vitamin K antagonists (VKAs) for preventing atrial fibrillation (AF)–related stroke. However, direct oral anticoagulants (DOACs) have an improved safety profile over VKAs, and their effect on cardiovascular and neurological outcomes relative to LAAC is unknown.ObjectivesThis study sought to compare DOACs with LAAC in high-risk patients with AF.MethodsLeft Atrial Appendage Closure vs. Novel Anticoagulation Agents in Atrial Fibrillation (PRAGUE-17) was a multicenter, randomized, noninferiority trial comparing LAAC with DOACs. Patients were eligible to be enrolled if they had nonvalvular AF; were indicated for oral anticoagulation (OAC); and had a history of bleeding requiring intervention or hospitalization, a history of a cardioembolic event while taking an OAC, and/or a CHA₂DS₂-VASc of ≥3 and HAS-BLED of >2. Patients were randomized to receive LAAC or DOAC. The primary composite outcome was stroke, transient ischemic attack, systemic embolism, cardiovascular death, major or nonmajor clinically relevant bleeding, or procedure-/device-related complications. The primary analysis was by modified intention to treat.ResultsA high-risk patient cohort (CHA₂DS₂-VASc: 4.7 ± 1.5) was randomized to receive LAAC (n = 201) or DOAC (n = 201). LAAC was successful in 181 of 201 (90.0%) patients. In the DOAC group, apixaban was most frequently used (192 of 201; 95.5%). At a median 19.9 months of follow-up, the annual rates of the primary outcome were 10.99% with LAAC and 13.42% with DOAC (subdistribution hazard ratio [sHR]: 0.84; 95% confidence interval [CI]: 0.53 to 1.31; p = 0.44; p = 0.004 for noninferiority). There were no differences between groups for the components of the composite endpoint: all-stroke/TIA (sHR: 1.00; 95% CI: 0.40 to 2.51), clinically significant bleeding (sHR: 0.81; 95% CI: 0.44 to 1.52), and cardiovascular death (sHR: 0.75; 95% CI: 0.34 to 1.62). Major LAAC-related complications occurred in 9 (4.5%) patients.ConclusionsAmong patients at high risk for stroke and increased risk of bleeding, LAAC was noninferior to DOAC in preventing major AF-related cardiovascular, neurological, and bleeding events. (Left Atrial Appendage Closure vs. Novel Anticoagulation Agents in Atrial Fibrillation [PRAGUE-17]; NCT02426944)     

The Detrimental Effect of RA Pacing on LA Function and Clinical Outcome in Cardiac Resynchronization Therapy

ObjectivesThis study assessed the impact of right-atrial (RA) pacing on left-atrial (LA) physiology and clinical outcome.BackgroundData for the effects of RA pacing on LA synchronicity, function, and structure after cardiac resynchronization therapy (CRT) are scarce.MethodsThe effect of RA pacing on LA function, morphology, and synchronicity was assessed in a prospective imaging cohort of heart failure (HF) patients in sinus rhythm with a guideline-based indication for CRT. Additionally, in a retrospective outcome cohort of consecutive HF patients undergoing CRT implantation, the relationship to RA pacing was assessed using various outcome endpoints. High versus low atrial pacing burden was defined as atrial pacing above or below 50% in both cohorts.ResultsA total of 36 patients were included in the imaging cohort (68 ± 11 years of age). Six months after CRT, patients with high RA pacing burden showed less improvement in LA maximum and minimum volumes and total emptying fraction (p < 0.05). Peak atrial longitudinal strain and reservoir and booster strain rates but not conduit strain rate improved after CRT in patients with low RA pacing burden but worsened in patients with high RA pacing burden (p < 0.05 for all). A high RA pacing burden induced significant intra-atrial dyssynchrony (maximum opposing wall delay: 44 ± 13 ms vs. 97 ± 17 ms, respectively; p = 0.022). A total of 569 patients were included in the outcome cohort. After covariate adjustments were made, a high RA pacing burden was associated with reduced LV reverse remodeling (β = 8.738; 95% confidence interval [CI]: 3.101 to 14.374; p = 0.002) and new-onset or recurrent atrial fibrillation (41% vs. 22%, respectively, at a median of 31 months [range 22 to 44 months follow-up]; p < 0.001). There were no differences in time to first HF hospitalization or all-cause mortality (p = 0.185) after covariate adjustment. However, in a recurrent event analysis, HF readmissions were more common in patients exposed to a high RA pacing burden (p = 0.003).ConclusionsRA pacing in CRT patients negatively influences LA morphology, function, and synchronicity, which is associated with worse clinical outcome, including diminished LV reverse remodeling, increased risk for new-onset or recurrent AF and heart failure readmission. Strategies reducing RA pacing burden may be warranted.     

Registro Español de Ablación con Catéter. XIX Informe Oficial de la Asociación del Ritmo Cardiaco de la Sociedad Española de Cardiología (2019)

Introduction and objectivesThis report presents the findings of the 2019 Spanish Catheter Ablation Registry.MethodsData collection was retrospective. A standardized questionnaire was filled by each of the participant centers.ResultsData sent by 102 centers were analyzed, with a total number of ablation procedures performed of 18 549 (the highest historically reported in this registry) for a mean of 181.9 ± 137.0 and a median of 144.5 procedures per center. The ablation targets most frequently treated were atrial fibrillation (n = 5164; 27.8%), cavotricuspid isthmus (n = 3925; 21.1%) and atrioventricular nodal reentrant tachycardia (n = 3768; 20.3%). A new peak is observed in the ablation of atrial fibrillation, increasing the distance from the other substrates. The overall success rate was again 91%. The rate of major complications was 1.9%, and the mortality rate was 0.03%. An electroanatomic mapping system was used in 44.5% of all procedures, with contact force-sensing irrigated catheters become the preferred for complex substrates, as atrial fibrillation (84.8%) or ventricular tachycardia (around 90%). 1.5% of the ablations were performed in pediatric patients.ConclusionsThe Spanish Catheter Ablation Registry enrolls systematically and uninterruptedly the ablation procedures performed in Spain, showing a progressive increasing in the number of ablations over the years with a high success rate and low percentages of complications.     

Calcium-Induced Autonomic Denervation in Patients With Post-Operative Atrial Fibrillation

BackgroundPost-operative atrial fibrillation (POAF) is associated with worse long-term cardiovascular outcomes.ObjectivesThis study hypothesized that injecting calcium chloride (CaCl₂) into the major atrial ganglionated plexi (GPs) during isolated coronary artery bypass grafting (CABG) can reduce the incidence of POAF by calcium-induced autonomic neurotoxicity.MethodsThis proof-of-concept study randomized 200 patients undergoing isolated, off-pump CABG to CaCl₂ (n = 100) or sodium chloride (sham, n = 100) injection. Two milliliters of CaCl₂ (5%) or sodium chloride (0.9%) was injected into the 4 major atrial GPs during CABG. All patients received 7-day continuous telemetry and Holter monitoring. The primary outcome was incidence of POAF (≥30 s) in 7 days. Secondary outcomes included length of hospitalization, POAF burden, average ventricular rate during AF, plasma level of inflammatory markers, and actionable antiarrhythmic therapy to treat POAF.ResultsThe POAF incidence was reduced from 36% to 15% (hazard ratio: 0.366; 95% confidence interval: 0.211 to 0.635; p = 0.001). Length of hospitalization did not differ between the 2 groups. POAF burden (first 7 post-operative days), the use of amiodarone or esmolol, and the incidence of atrial couplets and nonsustained atrial tachyarrhythmias were significantly reduced in the CaCl₂ group. Heart rate variability data showed a decrease in both high-frequency and low-frequency power in the CaCl₂ group with a preserved low-frequency/high-frequency ratio, suggesting that the sympathetic/parasympathetic balance was not perturbed by CaCl₂ injection.ConclusionsInjection of CaCl₂ into the 4 major atrial GPs reduced the POAF hazard by 63%. Inhibition of GP function by Ca-mediated neurotoxicity may underlie the therapeutic effect. (Calcium Autonomic Denervation Prevents Postoperative Atrial Fibrillation; ChiCTR1800019276)     

Registro Español de Ablación con Catéter. XX Informe Oficial de la Asociación del Ritmo Cardiaco de la Sociedad Española de Cardiología (2020)

Introduction and objectivesThis article reports the results of the 2020 Spanish Catheter Ablation Registry, a year marked by the SARS-CoV-2 pandemic.MethodsData were collected retrospectively through completion and return of a specific form by the participating centers.ResultsData from 97 centers (67 public, 30 private) were analyzed. A total of 15 169 ablation procedures were reported with a mean of 155 ± 117 and a median [interquartile range] of 115 [62-227]. Because of the SARS-CoV-2 pandemic, both procedures and participating centers markedly decreased (−3380 procedures, −18%) and there were 5 centers less than in 2019. The most common procedure continued to be atrial fibrillation ablation (4513; 30%), well ahead of the remaining substrates, followed by ablation of the cavotricuspid isthmus (3188; 21%), and intranodal re-entry tachycardia (2808; 18%). Ablation of these 3 substrates continued to form the bulk of the procedures. The total success rate was slightly lower than in previous years (88%) with a similar complication rate (n = 309; 2%) and mortality (n = 7; 0.04%). A total of 243 procedures were performed in pediatric patients (1.6%).ConclusionsThe Spanish Catheter Ablation Registry systematically and continuously reflects the national trajectory, which, in 2020, was markedly affected by the SARS-CoV-2 pandemic. Although slightly lower than in previous years, the success rate remained high, with a low complication rate.Full English text available from:www.revespcardiol.org/en     

Atrial Fibrillation and Transcatheter Repair of Functional Mitral Regurgitation: Evidence From a Meta-Regression

ObjectivesThe aim of this study was to assess the impact of atrial fibrillation (AF) on mortality and efficacy in patients with functional mitral regurgitation (FMR) undergoing MitraClip implantation.BackgroundAF is a common arrhythmia in patients with severe FMR undergoing transcatheter mitral valve repair with the MitraClip device. Although AF has been consistently shown to be associated with poor outcomes after mitral valve surgery, the impact of AF on outcomes of MitraClip placement in patients with FMR has not been well studied.MethodsProspective, retrospective registries, observational studies, and randomized controlled trials on MitraClip reporting AF and FMR as one of the variables from inception until January 2019 were included.ResultsOf the initial 1,694 studies, 15 studies met the inclusion criteria. From a total of 5,184 patients, 2,105 patients were identified to have FMR and AF. All-cause 30-day mortality in patients with FMR was 3.7% (95% confidence interval: 2.87 to 4.66) and 1-year mortality was 17.9% (95% confidence interval: 16.01 to 19.71). The meta-regression analysis studying the impact of AF among patients with FMR treated with the MitraClip demonstrated no difference in mortality at 30 days but demonstrated significantly increased mortality at 1 year (95% confidence interval: 0.0006 to 0.0027) (p = 0.004). AF did not influence procedural success.ConclusionsThis meta-regression identifies AF as an independent negative predictor of long-term mortality after MitraClip implantation in patients with FMR. The mechanism of worse outcomes in patients with AF requires further study.     

Risk Factors for the Development of Functional Tricuspid Regurgitation and Their Population-Attributable Fractions

ObjectivesThe objective of this study was to determine risk factors for progression to hemodynamically significant tricuspid regurgitation (TR) and the population burden attributable to these risk factors.BackgroundFew data are available with regard to risk factors associated with the development of hemodynamically significant functional TR.MethodsA total of 1,552 subjects were studied beginning with an index echocardiogram demonstrating trivial or mild TR. Risk factors for progression to moderate or severe TR were determined by using logistic regression and classification trees. Population attributable fractions were calculated for each risk factor.ResultsDuring a median follow-up time of 38 (interquartile range [IQR]: 26 to 63) months, 292 patients (18.8%) developed moderate/severe TR. Independent predictors of TR progression were age, female sex, heart failure, pacemaker electrode, atrial fibrillation (AF), and indicators of left heart disease, including left atrial (LA) enlargement, elevated pulmonary artery pressure (PAP), and left-sided valvular disease. Classification and regression tree analysis demonstrated that the strongest predictors of TR progression were PAP of ≥36 mm Hg, LA enlargement, age ≥60 years, and AF. In the absence of these 4 risk factors, progression to moderate or severe TR occurred in ∼3% of patients. Age (28.4%) and PAP (20.5%) carried the highest population-attributable fractions for TR progression. In patients with TR progression, there was a marked concomitant increase of incident cases of elevated PAP (40%); mitral and aortic valve intervention (12%); reductions in left ventricular ejection fraction (19%), and new AF (32%) (all p < 0.01).ConclusionsTR progression is determined mainly by markers of increased left-sided filling pressures (PAP and LA enlargement), AF, and age. At the population level, age and PAP are the most important contributors to the burden of significant TR. TR progression entails a marked parallel increase in the severity of left-sided heart disease.     

Alcohol-Mediated Renal Denervation Using the Peregrine System Infusion Catheter for Treatment of Hypertension

ObjectivesThe aim of this multicenter, open-label trial was to evaluate the safety and efficacy of alcohol-mediated renal denervation using a novel catheter system (the Peregrine System Infusion Catheter) for the infusion of dehydrated alcohol as a neurolytic agent into the renal periarterial space.BackgroundThe number of hypertensive patients with uncontrolled blood pressure (BP) remains unacceptably high. The renal sympathetic nervous system has been identified as an attractive therapeutic target.MethodsForty-five patients with uncontrolled hypertension on ≥3 antihypertensive medications underwent bilateral renal denervation using the Peregrine Catheter with 0.6 ml alcohol infused per renal artery.ResultsAll patients were treated as intended. Mean 24-h ambulatory BP reduction at 6 months versus baseline was −11 mm Hg (95% confidence interval [CI]: −15 to −7 mm Hg) for systolic BP and −7 mm Hg (95% CI: −9 to −4 mm Hg) for diastolic BP (p < 0.001 for both). Office systolic BP was reduced by −18/−10 mm Hg (95% CI: −25 to −12/−13 to −6 mm Hg) at 6 months. Antihypertensive medications were reduced in 23% and increased in 5% of patients at 6 months. Adherence to the antihypertensive regimen remained stable over time. The primary safety endpoint, defined as the absence of periprocedural major vascular complications, major bleeding, acute kidney injury, or death within 1 month, was met in 96% of patients (95% CI: 85% to 99%). Two patients had major adverse events of periprocedural access-site pseudoaneurysms, with major bleeding in one. There were no deaths or instances of myocardial infarction, stroke, transient ischemic attack, or renal artery stenosis. Transient microleaks were noted in 42% and 49% of the left and right main renal arteries, respectively. There were 2 cases of minor vessel dissection that resolved without treatment.ConclusionsPrimary results from this trial suggest that alcohol-mediated renal denervation using the Peregrine Catheter safely reduces blood pressure and as such may represent a novel approach for the treatment of hypertension.     

Left Atrial Strain Impairment Precedes Geometric Remodeling as a Marker of Post-Myocardial Infarction Diastolic Dysfunction

ObjectivesThe aims of this study were to test the magnitude of agreement between echocardiography (echo)- and cardiac magnetic resonance (CMR)–derived left atrial (LA) strain and to study their relative diagnostic performance in discriminating diastolic dysfunction (DD) and predicting atrial fibrillation (AF).BackgroundsPeak atrial longitudinal strain (PALS) is a novel performance index. Utility of echo-quantified LA strain has yet to be prospectively tested in relation to current DD guidelines or compared to CMR.MethodsThe study population comprised 257 post-myocardial infarction (MI) patients undergoing echo and CMR, including prospective derivation (n = 157) and clinical validation (n = 100) cohorts. DD was graded on echo using established consensus guidelines blinded to strain results.ResultsPALS on both echo and CMR was nearly 2-fold lower among patients with versus no DD (p < 0.001) and was significantly different in those with mild versus no DD (p < 0.01). In contrast, LA geometric parameters including echo- and CMR-derived volumes were significantly different between advanced versus no DD groups (p < 0.001) but not between groups with mild versus no DD (all p > 0.05). Echo and CMR PALS yielded small differences irrespective of orientation and similar diagnostic performance for DD in the derivation (area under the curve [AUC]: 0.70 to 0.78) and validation (AUC: 0.75 to 0.78) cohorts. Impaired PALS on both modalities was independently associated with MI size (p < 0.001). During 4.4 ± 3.8 years of follow-up in the derivation cohort, 8% developed AF. Both 2-chamber echo- and CMR-derived PALS stratified arrhythmic risk (p = 0.004 and p = 0.02, respectively), including a 4-fold difference among patients in the lowest versus remainder of quartiles of echo-derived PALS (24% vs. 6%). Similarly, echo and CMR PALS were lower (both p < 0.05) among patients with subsequent heart failure hospitalizations.ConclusionsEcho-derived PALS parallels results of CMR, yields incremental diagnostic utility versus LA geometry for stratifying presence and severity of DD, and improves prediction of AF and congestive heart failure after MI.