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.
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.
Early repolarization (ER) is typically observed in highly trained athletes as a physiologic consequence of increased vagal tone. The variant of anterior (V1 to V3) ER characterized by “domed” ...ST-segment elevation and negative T wave raises problems of differential diagnosis with the “coved-type” electrocardiographic pattern seen in Brugada syndrome (BS). This study was designed to identify electrocardiographic criteria for distinguishing athlete's ER from BS. The study compared the electrocardiographic tracings of 61 healthy athletes (80% men, median age 23 ± 8 years), showing “domed” ST-segment elevation and negative T wave in leads V1 to V3, with those of 92 consecutive age- and sex-matched BS patients with a “coved-type” electrocardiographic pattern. The electrocardiographic analysis focused on the ST-segment elevation at J point (STJ ) and at 80 milliseconds after J point (ST80 ). Athletes had a lower maximum amplitude of STJ (1.46 ± 0.7 vs 3.25 ± 0.6 mm, p <0.001) and lower STJ /ST80 (0.8 ± 0.3 vs 1.6 ± 0.3, p <0.001). All patients (100%) with BS showed a downsloping ST-segment configuration (STJ /ST80 >1) versus only 2 (3%) athletes (p <0.001). An upsloping ST-segment configuration (STJ /ST80 <1) showed a sensitivity of 97%, a specificity of 100%, and a diagnostic accuracy of 98.7% for the diagnosis of ER. At multivariate analysis, STJ /ST80 ratio remained the only independent predictor for ER (odds ratio 87, 95% confidence interval 19 to 357, p <0.001). In conclusion, the STJ /ST80 ratio is a highly accurate electrocardiographic parameter for differential diagnosis between anterior ER of the athlete and BS. Our results may help in reducing the number of athletes who undergo expensive diagnostic workup or are unnecessarily disqualified from competition for changes that fall within the normal range of athlete's heart.
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 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.
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.