The aims of the present study were to investigate the incidence and characteristics of conduction disorders (CDs) after transcatheter aortic valve implantation (TAVI), to analyze the predictors of ...permanent pacemaker (PPM) implantation, and to evaluate the outcomes of CDs over time. In particular, we sought to investigate whether the depth of deployment and other technical aspects of valve implantation might predict the need for PPM implantation after TAVI. TAVI has been reported to favor the onset or worsening of CDs often requiring PPM implantation. A total of 70 patients with aortic stenosis due to dystrophic calcification underwent TAVI with third-generation CoreValve Revalving System from May 2007 to April 2009. We collected electrocardiograms at baseline, during TAVI, during hospitalization and at the 1-, 3-, 6-, and 12-month follow-up visits thereafter. The clinical, anatomic, and procedural variables were tested to identify the predictors of PPM implantation. The PPM dependency at follow-up was analyzed. Six patients were excluded from the analysis because of a pre-existing PPM. Of the 64 patients, 32 (50%) had one or more atrioventricular-intraventricular CDs at baseline. TAVI induced a worsening in the CDs in 49 (77%) of the 64 patients, with 25 (39%) requiring in-hospital PPM implantation. On multivariate analysis, the independent predictors of PPM implantation were the depth of the prosthesis implantation (p = 0.039) and the pre-existing right bundle branch block (p = 0.046). A trend in the recovery of the CDs over time was recorded, although 2 patients required PPM implantation 1 month after discharge for late complete atrioventricular block. In conclusion, TAVI often induces or worsens CDs, requiring PPM in more than one third of patients, although a trend in the recovery of CDs during the midterm was recorded. The independent predictors of PPM implantation were the depth of prosthesis implantation and pre-existing right bundle branch block.
Objectives The purpose of this study is to assess the effectiveness of defibrillation testing (DT) in patients undergoing implantable cardioverter-defibrillator (ICD) insertion. Background Although ...DT is considered a standard procedure during ICD implantation, its usefulness has not been definitively proven. Methods The SAFE-ICD (Safety of Two Strategies of ICD Management at Implantation) study is a prospective observational study designed to evaluate the outcome of 2 strategies: performing defibrillation testing (DT+) versus not performing defibrillation testing (DT−) during de novo ICD implants. No deviation from the centers' current practice was introduced. In all, 2,120 consecutive patients (836 DT+ and 1,284 DT−) age ≥18 years were enrolled at 41 Italian centers from April 2008 to May 2009 and followed up for 24 months until June 2011. The primary endpoint was a composite of severe complications at ICD implant and sudden cardiac death or resuscitation at 2 years. Results The primary endpoint occurred in 34 patients: 12 intraoperative complications (8 in DT+ group; 4 in DT− group) and 22 during follow-up (10 in DT+ group; 12 in DT− group). Overall, the estimated yearly incidence (95% confidence interval) was DT+ 1.15% (0.73 to 1.83) and DT− 0.68% (0.42 to 1.12). The difference between the 2 groups was negligible: 0.47% per year (−0.15 to 1.10). Mortality from any cause was similar at 2 years (adjusted hazard ratio: 0.97 0.76 to 1.23, p = 0.80). Conclusions In this large cohort of new ICD implants, event rates were similar and extremely low in both groups. These data indicate a limited clinical relevance for DT testing, thus supporting a strategy of omitting DT during an ICD implant. (Safety of Two Strategies of ICD Management at Implantation SAFE-ICD; NCT00661037 )
Three-Dimensional Electroanatomical Voltage Mapping and Histologic Evaluation of Myocardial Substrate in Right Ventricular Outflow Tract Tachycardia Domenico Corrado, Cristina Basso, Loira Leoni, ...Barbara Tokajuk, Pietro Turrini, Barbara Bauce, Federico Migliore, Andrea Pavei, Giuseppe Tarantini, Massimo Napodano, Angelo Ramondo, Gianfranco Buja, Sabino Iliceto, Gaetano Thiene Twenty-seven patients (15 men and 12 women, age 33.9 ± 8 years) with right ventricular outflow tract (RVOT) tachycardia and no right ventricular (RV) dilation/dysfunction were studied by electroanatomical voltage mapping (EVM) and endomyocardial biopsy (EMB) before catheter ablation. Right ventricular EVM was normal in 20 of 27 patients (74%, group A), whereas the other 7 patients (26%, group B) showed RVOT electroanatomical scars that correlated with fibrofatty myocardial replacement at EMB (p < 0.001). Three of 7 patients (43%) from group B received an implantable defibrillator during the follow-up, compared with no patients from group A (p = 0.012). Electroanatomical voltage mapping is able to identify RVOT tachycardia due to concealed arrhythmogenic RV cardiomyopathy/dysplasia.
Permanent atrial pacing usually involves lead placement in the right atrial appendage (RAA). Anatomical studies addressing features predisposing to complications are scanty.
To assess the morphology ...of RAA in the perspective of pacing, including the morphology of tenia sagittalis (TS) and the spatial relationship with the aorta.
The gross anatomy of the RAA has been analyzed in a consecutive series of 100 hearts following a case of iatrogenic perforation of the aorta by active fixation lead located in the RAA. Transmural RAA sections were taken from 40 hearts to assess the wall thickness at the level of pectinate muscles (PMs) and of inter-PMs spaces and the distance between adjacent PMs.
The TS was present in 90% of cases (single trunk, 76%; double trunk, 13%; and triple trunk, 1%), demarcating the proximal antral RAA region (facing the adjacent aorta) from the distal saccular RAA region (facing the pulmonary infundibulum). The RAA free wall in the inter-PMs spaces is usually paper-thin and translucent. Histomorphometric analysis reveals that the RAA wall mean thickness was 1.38 ± 0.05 mm (range 0.64-4.25 mm) at the level of PMs and 0.39 ± 0.23 mm (range 0.09-1.05 mm) at the level of inter-PMs spaces. The mean distance between adjacent PMs was 0.88 ± 0.99 mm (range 0.04-4.12 mm).
In 90% of hearts, a well-defined TS separates the distal saccular from the proximal antral RAA, the latter being closely adjacent to the ascending aorta. The paper-thin wall between PMs is potentially at risk of perforation, and aortic injury could occur when active fixation leads are anchored in the antral RAA, as demonstrated in an iatrogenic fatal case.
The diagnostic Brugada-electrocardiogram (Br-ECG) is characterized by "coved-type" ST-segment elevation (type 1) in V(1) to V(2)/V(3). The sodium-channel blocker test is clinically used to unmask ...diagnostic Br-ECG in patients with nondiagnostic "saddle-back" Br-ECG (type 2 and type 3).
To assess the prognostic value of the sodium-channel blockers test in individuals with a nondiagnostic Br-ECG.
We studied 153 consecutive patients (128 men; age 41.7 ± 14.0 years) with a type 2/3 Br-ECG who underwent a sodium-channel blocker test with either flecainide (48%) or ajmaline (52%). Nondiagnostic Br-ECGs were identified during the evaluation of cardiac arrest in 5 patients (3%), syncope in 36 (24%), cascade family screening in 48 (31%), and incidental ECG in 64 (42%). A spontaneous type 1 Br-ECG was systematically excluded by serial ECGs (6.1 ± 0.4) and recording of right precordial leads both at standard and second and third intercostal spaces.
The sodium-channel blocker test result was positive in 76 (50%) patients. During a follow-up of 59 ± 33 months, 9 (5.9%) patients experienced events such as syncope (n = 4), appropriate interventions of defibrillator (n = 4), or sudden death (n = 1). A positive sodium-channel blocker test was associated with a significantly higher event rate in symptomatic patients (P = .01) but not in asymptomatic individuals (P = .18). No events occurred among asymptomatic individuals with an incidental nondiagnostic Br-ECG.
In asymptomatic individuals with a nondiagnostic Br-ECG, the incidence of events is low regardless of the sodium-channel blocker test result while in symptomatic patients a positive sodium-channel blocker test result is associated with an adverse arrhythmic outcome and may contribute to risk stratification.
Abstract This is the case of a 28-year-old woman with sustained supraventricular tachycardia induced only by monomorphic ventricular couplets but not by isolated extrasystoles. The careful ...examination of electrocardiogram (ECG) was able to identify the mechanism of the tachycardia in the absence of electrophysiologic investigation. The tachycardia resulted sustained and symptomatic only during periods.
Although the effects of air pollution on mortality have been clearly shown in many epidemiological and observational studies, the pro-arrhythmic effects remain unknown. We aimed to assess the ...short-term effects of air pollution on ventricular arrhythmias in a population of high-risk patients with implantable cardioverter-defibrillators (ICDs) or cardiac resynchronisation therapy defibrillators (ICD-CRT).
In this prospective multicentre study, we assessed 281 patients (median age 71 years) across nine centres in the Veneto region of Italy. Episodes of ventricular tachycardia and ventricular fibrillation that were recorded by the diagnostic device were considered in this analysis. Concentrations of particulate matter of less than 10 μm (PM10) and less than 2·5 μm (PM2·5) in aerodynamic diameter, carbon monoxide, nitrogen dioxide, sulphur dioxide, and ozone were obtained daily from monitoring stations, and the 24 h median value was considered. Each patient was associated with exposure data from the monitoring station that was closest to their residence. Patients were followed up for 1 year and then scheduled to have a closing visit, within 1 more year. This study is registered with ClinicalTrials.gov, number NCT01723761.
Participants were enrolled from April 1, 2011, to Sept 30, 2012, and follow-ups (completed on April 5, 2014) ranged from 637 to 1177 days (median 652 days). The incidence of episodes of ventricular tachycardia and ventricular fibrillation correlated significantly with PM2·5 (p<0·0001) but not PM10. An analysis of ventricular fibrillation episodes alone showed a significant increase in risk of higher PM2·5 (p=0·002) and PM10 values (p=0·0057). None of the gaseous pollutants were significantly linked to the occurrence of ventricular tachycardia or ventricular fibrillation. In a subgroup analysis of patients with or without a previous myocardial infarction, only the first showed a significant association between particulate matter and episodes of ventricular tachycardia or ventricular fibrillation.
Particulate matter has acute pro-arrhythmic effects in a population of high-risk patients, which increase on exposure to fine particles and in patients who have experienced a previous myocardial infarction. The time sequence of the arrhythmic events suggests there is an underlying neurally mediated mechanism. From a clinical point of view, the results of our study should encourage physicians to also consider environmental risk when addressing the prevention of arrhythmic events, particularly in patients with coronary heart disease, advising them to avoid exposure to high levels of fine particulate matter.
There was no funding source for this study.
Abstract Objective The purpose of this study was to evaluate the impact of adhering to a strict follow up regimen on mid-term efficacy of intraoperative radiofrequency ablation in maintaining sinus ...rhythm for patients with atrial fibrillation undergoing cardiac surgery. Methods We enrolled 52 patients with atrial fibrillation and valve disease divided in 2 groups: group 1 (26 patients) underwent intraoperative radiofrequency ablation and was followed by a team of skilled cardiologists who treated recurrences with amiodarone and electrical cardioversion; group 2 (26 patients) was treated with intraoperative radiofrequency ablation but patients were thereafter treated by their local hospital or personal cardiologist. Results There were no intraoperative deaths or complications related to radiofrequency ablation. Twenty four months after the operation, freedom from atrial fibrillation was 60% in group 1 and 32% in group 2 ( p = 0.02). Group 1 also showed a reduction in atrial volume ( p ≤ 0.05). Conclusion Postoperative follow up with electrical and pharmacologic cardioversion combined with radiofrequency ablation achieves higher rate of sinus rhythm maintenance. After ablation, electrical cardioversion is effective even in patients with enlarged left atrium, long history of atrial fibrillation, or previous failed electrical cardioversion.
Abstract Right ventricular lead perforation is a rare but serious and potentially life-threatening complication of pacemaker or defibrillator lead implantation. This report describes a patient with ...Brugada syndrome in whom the diagnosis of asymptomatic right ventricular perforation by an implantable cardioverter defibrillator lead was detected 12 days after implantation, thanks to a report from home monitoring system. The patient was admitted to our institution, where the lead was explanted and replaced. This case illustrates the potential lifesaving benefit of the home monitoring system in patients with implantable cardioverter defibrillator.
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