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Objectives: The aim of this study was to test the feasibility and usefulness of a new delayed-enhancement cardiac magnetic resonance (DE-CMR)-guided approach to ablate gaps in redo procedures., Background: Recurrences of atrial fibrillation (AF) after pulmonary vein isolation (PVI) may be related to gaps at the ablation lines. DE-CMR allows identification of radiofrequency lesions and gaps (CMR gaps)., Methods: Fifteen patients undergoing repeated AF ablations were included (prior procedure was PVI in all patients and roof-line ablation in 8 patients). Pre-procedure 3-dimensional (3D) DE-CMR was performed with a respiratory-navigated (free-breathing) and electrocardiographically gated inversion-recovery gradient-echo sequence (voxel size 1.25 × 1.25 × 2.5 mm). Endocardium and epicardium were manually segmented to create a 3D reconstruction (DE-CMR model). A pixel signal intensity map was projected on the DE-CMR model and color-coded (thresholds 40 ± 5% and 60 ± 5% of maximum intensity). The DE-CMR model was imported into the navigation system to guide the ablation of CMR gaps, with the operator blinded to electrical data. Fifteen conventional procedures were used as controls to compare procedural duration, radiofrequency, and fluoroscopy times., Results: Fifteen patients (56 pulmonary veins [PVs]; 57 ± 8 years of age; 9 with paroxysmal AF) were analyzed. In total, 67 CMR gaps were identified around PVs (mean 4.47 gaps/patient; median length 13.33 mm/gap) and 9 at roof line. All of the electrically reconnected PVs (87.5%) had CMR gaps. The site of electrical PV reconnection (assessed by circular mapping catheter) matched with a CMR gap in 79% of PVs. CMR-guided ablation led to reisolation of 95.6% of reconnected PVs (median radiofrequency time of 13.3 [interquartile range: 7.5 to 21.7] min/patient) and conduction block through the roof line in all patients (1.4 [interquartile range: 0.7 to 3.1] min/patient). Compared with controls, the CMR-guided approach shortened radiofrequency time (1,441 ± 915 s vs. 930 ± 662 s; p = 0.026) but not the procedural duration or fluoroscopy time., Conclusions: DE-CMR can successfully guide repeated PVI procedures by accurately identifying and localizing gaps and may reduce procedural duration and radiofrequency application time., (Copyright © 2014 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

The Brugada syndrome (BS) is a hereditary disease characterized by typical electrocardiographic alterations (elevation of the ST segment in right precordial leads) that affects young individuals without structural heart disease, predisposing them to ventricular arrhythmias and sudden death (SD). Several genetic mutations of different subunits of the sodium, calcium and potassium channel have been involved. The majority of patients with BS remain asymptomatic; however, the most frequent symptoms are syncope and/or SD secondary to polymorphic ventricular tachycardia (PVT) or ventricular fibrillation (VF). Electrocardiographic manifestations of the BS are typically dynamic and occasionally only become apparent after the administration of a sodium channel blocker or with fever. Risk stratification is mainly based on symptoms and the surface electrocardiogram. However, in asymptomatic patients, risk evaluation is still controversial and requires further studies. This review provides an updated summary of the BS from the point of view of genetic, clinical manifestations, risk stratification and management.

Background: Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a cardiac disease characterized by the presence of fibrofatty replacement of the right ventricular myocardium, which may cause ventricular arrhythmias and sudden cardiac death. Pathogenic mutations in several genes encoding mainly desmosomal proteins have been reported. Our aim is to perform genotype-phenotype correlations to establish the diagnostic value of genetics and to assess the role of mutation type in age-related penetrance in ARVC., Methods and Results: Thirty unrelated Spanish patients underwent a complete clinical evaluation. They all were screened for PKP2, DSG2, DSC2, DSP, JUP and TMEM43 genes. A total of 70 relatives of four families were also studied. The 30 patients fulfilled definite disease diagnostic criteria. Genetic analysis revealed a pathogenic mutation in 19 patients (13 in PKP2, 3 in DSG2, 2 in DSP, and 1 in DSC2). Nine of these mutations created a truncated protein due to the generation of a stop codon. Familial assessment revealed 28 genetic carriers among family members. Stop-gain mutations were associated to a later age of onset of ARVC, without differences in the severity of the pathology., Conclusions: Familial genetic analysis helps to identify the cause responsible for the pathology. In discrepancy with previous studies, the presence of a truncating protein does not confer a worse severity. This information could suggest that truncating proteins may be compensated by the normal allele and that missense mutations may act as poison peptides.

Aims: The Atrial Fibrillation Ablation Pilot Study is a prospective registry designed to describe the clinical epidemiology of patients undergoing an atrial fibrillation (AFib) ablation, and the diagnostic/therapeutic processes applied across Europe. The aims of the 1-year follow-up were to analyse how centres assess in routine clinical practice the success of the procedure and to evaluate the success rate and long-term safety/complications., Methods and Results: Seventy-two centres in 10 European countries were asked to enrol 20 consecutive patients undergoing a first AFib ablation procedure. A web-based case report form captured information on pre-procedural, procedural, and 1-year follow-up data. Between October 2010 and May 2011, 1410 patients were included and 1391 underwent an AFib ablation (98.7%). A total of 1300 patients (93.5%) completed a follow-up control 367 ± 42 days after the procedure. Arrhythmia documentation was done by an electrocardiogram in 76%, Holter-monitoring in 52%, transtelephonic monitoring in 8%, and/or implanted systems in 4.5%. Over 50% became asymptomatic. Twenty-one per cent were re-admitted due to post-ablation arrhythmias. Success without antiarrhythmic drugs was achieved in 40.7% of patients (43.7% in paroxysmal AF; 30.2% in persistent AF; 36.7% in long-lasting persistent AF). A second ablation was required in 18% of the cases and 43.4% were under antiarrhythmic treatment. Thirty-three patients (2.5%) suffered an adverse event, 272 (21%) experienced a left atrial tachycardia, and 4 patients died (1 haemorrhagic stroke, 1 ventricular fibrillation in a patient with ischaemic heart disease, 1 cancer, and 1 of unknown cause)., Conclusion: The AFib Ablation Pilot Study provided crucial information on the epidemiology, management, and outcomes of catheter ablation of AFib in a real-world setting. The methods used to assess the success of the procedure appeared at least suboptimal. Even in this context, the 12-month success rate appears to be somewhat lower to the one reported clinical trials., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.)

Aims: Pulmonary vein isolation (PVI) induces left atrial (LA) volume reduction, known as reverse remodelling (RR). The related changes in LA shape have not yet been evaluated. Left atrial sphericity (LASP) is a new shape-based marker of remodelling that compares LA geometry and a perfect sphere and is a powerful predictor of PVI success. We aimed to evaluate the effect of PVI on LASP and describe the concept of spherical and volumetric RR., Methods and Results: Left atrial sphericity and volume were automatically obtained with self-customized software using a magnetic resonance imaging-based three-dimensional reconstruction of LA. Reverse remodelling was defined as improvement in LASP (spherical RR) or volume reduction (volumetric RR). In a series of 102 patients, spherical and volumetric RR was observed in 42.2 and 69%, respectively. Patients with paroxysmal atrial fibrillation (AF) had higher probability to present spherical RR as compared with patients with persistent AF (50.8 vs. 29.3%, P = 0.03). Patients with persistent AF showed significant post-procedural worsening of LASP (81.9 vs. 82.9%, P = 0.04). Patients with no recurrence showed a trend towards a higher proportion of spherical RR compared with those with recurrences (46.2 vs. 32.4%, respectively); no differences were observed in volumetric RR (62.1 vs. 62.9%, respectively). Paroxysmal AF was the only independent predictor of spherical RR., Conclusion: Pulmonary vein isolation leads to spherical RR in a substantial proportion of patients, and in higher proportion of patients with paroxysmal AF. Reverse remodelling may be caused by a combination of scarring and myocardial structural recovery. Changes in LASP might be more specific than volume reduction to detect favourable remodelling., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.)

Background: The identification of conducting channels (CCs) based on its relative high voltage or the presence of electrograms with delayed components has been proposed for substrate-guided scar-related ventricular tachycardia (VT) ablation. The relationship of these channels with the VT isthmuses remains unclear., Objective: To assess the link between CCs identified during sinus rhythm (SR) and VT isthmuses in patients with arrhythmogenic right ventricular cardiomyopathy (ARVC)., Methods: Twenty-two consecutive patients with ARVC undergoing substrate-guided VT ablation (scar dechanneling technique) were analyzed. High-density endocardial and epicardial electroanatomic maps were obtained during SR. Standard bipolar cutoff values (0.5-1.5 and <0.5 mV) were used to define border zone and dense scar. The CCs were identified by voltage threshold adjustment (voltage channels) or by tagging the electrograms with delayed components that are sequentially activated (late potential channels)., Results: A total of 87 CCs were identified; 65 (74.7%) of them on the epicardial surface. Twenty-four (27.6%) CCs were voltage channels, and compared with late potential CCs, these had a higher bipolar voltage (0.96 [0.48-1.29] mV vs 0.39 [0.26-0.50] mV; P < .001] and required more radiofrequency applications (5 [4-7] vs 3 [2-5]; P = .048]. Eighteen (90%) of 20 identified VT isthmuses were located on the epicardium. Only 8 (40%) VT isthmuses were related to a voltage CC. The remaining 12 (60%) VT isthmuses were linked to a late potential CC., Conclusion: Late potential CCs more frequently act as the VT substrate in ARVC and therefore should also be considered to guide SR substrate-guided ablation., (Copyright © 2014 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.)

Atrial fibrillation is a frequent complication in the perioperative period. When it appears there is an increased risk of perioperative morbidity due to stroke, thromboembolism, cardiac arrest, myocardial infarction, anticoagulation haemorrhage, and hospital readmissions. The current article focuses on the recommendations for the management of perioperative atrial fibrillation based on the latest Clinical Practice Guidelines on atrial fibrillation by the European Society of Cardiology and the Spanish Society of Cardiology. This article pays special attention to the preoperative management, as well as to the acute perioperative episode. For this reason, the latest recommendations for the control of cardiac frequency, antiarrhythmic treatment and anticoagulation are included., (Copyright © 2012 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Published by Elsevier España. All rights reserved.)

Background: Optimization of atrioventricular (AV) and interventricular (VV) intervals may improve cardiac resynchronization therapy (CRT) response but is a complex task. Fusion with intrinsic conduction may increase the benefit of CRT. The aim was to describe fusion-optimized intervals (FOI), a new method of optimizing CRT based on QRS duration., Methods and Results: Seventy-six consecutive patients with preserved AV conduction who received CRT were prospectively included. The AV interval was optimized by searching the narrowest QRS obtained within the fusion band during left ventricular (LV) pacing. The VV interval was then adjusted, comparing QRS duration in simultaneous biventricular, LV preexcitation (-30 milliseconds), right ventricular (RV) preexcitation (-30 milliseconds) and LV-only pacing. A substudy in 31 patients evaluated the invasive LV +dP/dtmax . The best fusion-optimized AV interval was 136 ± 30 milliseconds during atrial sensing and 192 ± 35 milliseconds during atrial pacing. The best QRS was obtained with simultaneous biventricular pacing in 28 patients (37%), LV preexcitation in 22 (29%), LV-only in 20 (26%), and RV preexcitation in 6 (8%). Baseline QRS was shortened more by FOI (59 ± 19 milliseconds) than by nominal settings (40 ± 21 milliseconds; P < 0.001). Sixty-five patients (86%) showed >10% shortening of the baseline QRS with FOI; none prolonged the QRS duration by FOI compared to nominal settings. All echocardiographic asynchrony parameters were corrected by FOI. Baseline +dP/dtmax improvement was greater in FOI (127 ± 95 mmHg/seconds) than in nominal settings (102 ± 71 mmHg/seconds; P = 0.05)., Conclusion: The FOI method is feasible, further reduces QRS duration, and improves acute hemodynamic response compared to nominal programming of CRT., (© 2013 Wiley Periodicals, Inc.)

Aims: A maximum percentage of ventricular pacing is mandatory to obtain a good response to CRT. Atrioventricular junction (AVJ) ablation has been recommended to attain this objective in patients with AF., The Aims of Our Study Were: (i) to determine whether the presence of complete AVJ block (induced or spontaneous) improves survival in patients with permanent AF treated with CRT and (ii) to analyse the predictors of mortality in AF patients treated with CRT., Methods and Results: From a series of 608 patients treated with CRT in our centre from 2000 to 2011, a cohort of 155 patients with permanent AF was analysed. Patients in AF were divided into two groups, AF + AVJ block [76 (49%)] and AF non-AVJ block [79 (51%)]. Mean follow-up was 30 months (interquartile range 13-51 months). During the follow-up, 62 patients died. Overall and cardiovascular mortality were similar between both groups: hazard ratio (HR) 0.85, 95% confidence interval (CI) 0.51-1.39, P = 0.51 and HR 0.94, 95% CI 0.52-1.68, P = 0.82. Multivariate analysis identified three independent predictors of mortality: basal NYHA functional class IV (HR 2.25, 95% CI 1.12-4.22, P = 0.03), glomerular filtration rate (HR 0.98, 95% CI 0.96-0.99, P = 0.03), and LVEF (HR 0.94, 95% CI 0.89-0.99, P = 0.02)., Conclusions: AVJ block did not improve survival for patients in AF treated with CRT. Basal NYHA functional class IV, poor renal function, and LVEF were the independent predictors of mortality.

Introduction: Atrial fibrillation (AF) is a recognized treatable cause of tachycardiomyopathy (TMP), with class IIb indication for catheter ablation (CA). The aim of this study is to analyze the prevalence, clinical characteristics and effect of CA in patients with TMP and to evaluate TMP as a prognostic factor for AF recurrence in these patients (TMP group), compared to controls with normal left ventricular ejection fraction (LVEF) and patients with heart failure due to structural cardiomyopathy (HF group)., Methods and Results: The study groups included 659 consecutive patients undergoing CA between 2003 and 2011: TMP group (n = 61), HF group (n = 36) and control group (n = 562). Compared to controls, patients with TMP were younger, had a shorter AF course and more often had persistent AF. Regarding echocardiographic parameters, the TMP group had lower LVEF (40% vs. 62%, P < 0.05), larger left atrial diameter (LAD: 46 vs. 41 mm, P < 0.05) and LV end-diastolic diameter (LVEDD: 55 vs. 51 mm, P < 0.05) compared to controls, with significant improvement at six-month follow-up, including those patients with AF recurrence. The probability of being arrhythmia-free did not differ between the TMP group and the other groups after a first or last procedure. The only independent predictor of AF recurrence was LAD., Conclusions: Patients with tachycardiomyopathy secondary to AF benefit from CA, with a significant improvement in LVEF, LVEDD and LAD. The outcome after CA of this group did not differ from patients with no structural cardiomyopathy., (© 2013.)

The ventricular tachycardia (VT) monitoring zone in implantable cardioverter defibrillators (ICDs) is usually programmed to detect slow VTs. However, it is not well known whether programming this zone can affect the ICD arrhythmia redetection or confirmation criteria. We report two cases of inappropriate ICD shocks due to the programming of a slow VT monitoring zone in the same device model.

Background: Atrial fibrillation (AF) ablation outcome is mainly determined by atrial remodeling that, nowadays, is only estimated through clinical presentation (persistent vs. paroxysmal) and left atrial (LA) dimension. The aim of the study was to stage the atrial remodeling process using the Left Atrial Sphericity (LASP) and determine whether this technique may help to predict AF ablation outcome., Methods: Consecutive patients who underwent contrast-enhanced cardiac magnetic resonance angiography before AF ablation were included in the study. Three-dimensional reconstruction of LA excluding pulmonary veins and the LA appendage was used to define the LA cavity. The LASP was automatically obtained with self-customized software., Results: 106 patients were included and categorized in 3 groups (Gs): discoid-LA (G1), intermediate-LA (G2), and spherical-LA (G3). The G3 patients had larger LA anteroposterior diameter than G1 and G2 patients (47 ± 7 vs 43 ± 6 and 39 ± 5 mm; P < 0.001), greater LA volume (90 ± 39 vs 86 ± 24 and 73 ± 20 mm; P = 0.012), and higher prevalence of persistent AF (75% vs 48% and 29%; P = 0.034) structural heart disease (75% vs 19% and 19%; P < 0.001), and AF recurrence at 12 months follow-up (58% vs 29% and 5%, P < 0.001). The LASP had linear correlation to predicted probability of recurrence. Multivariate analysis identified LASP (OR 1.320 [1.096-1.591], P = 0.004) and hypertension (OR 3.694 [1.282-10.645]; P = 0.016) as independent risk factors for arrhythmia recurrence., Conclusion: Left Atrial Sphericity is a new independent predictor of recurrence after AF ablation and may be useful in selecting the best candidates for AF ablation., (© 2013 Wiley Periodicals, Inc.)

Aims: The Atrial Fibrillation Ablation Pilot Study is a prospective, multinational registry conducted by the European Heart Rhythm Association of the European Society of Cardiology that has been designed to describe the clinical epidemiology of patients undergoing an atrial fibrillation (AFib) ablation procedure, and the diagnostic/therapeutic processes applied in these patients across Europe. We present the results of the short-term (in-hospital) analysis., Methods and Results: A total of 72 centres in 10 European countries were asked to enrol 20 consecutive patients scheduled for a first AFib ablation procedure. Between October 2010 and May 2011, 1410 patients were included, of which 1391 underwent an AFib ablation (98.7%). The median age was 60 years [inter-quartile range (IQR) 52-66], and 28% were females. Two-thirds presented paroxysmal AFib and 38% lone AFib. Symptoms were present in 86%. The indications for ablation were mostly symptomatic AFib, but in over a third of patients there was also a desire for a drug-free lifestyle and the maintenance of sinus rhythm. Pulmonary vein isolation was attempted in 98.4% of patients, the roof line in 21.3% and the mitral isthmus line in 12.8%. Complex-fractionated atrial electrograms were targeted in 17.9% and the ganglionated plexi in 3.3%. Complications occurred in 7.7%, of which 1.7% was major (i.e. cardiac perforation, myocardial infraction, endocarditis, cardiac arrest, stroke, hemothorax, pneumothorax, and sepsis). The median duration of hospitalization was 3 days (IQR 2-4). At discharge, 91.4% of patients were in sinus rhythm, 88.3% of patients were given vitamin K antagonists, and 67% antiarrhythmic medication. There was one death after the ablation procedure., Conclusion: The AFib Ablation Pilot Study provides crucial information on AF ablation in clinical practice across Europe. These data are relevant for further improvement of the management strategies of patients suffering from atrial fibrillation.

Background: The proximity of the outflow tracts (OTs) frequently results in an overlap in surface electrocardiographic features of ventricular arrhythmias originating from this anatomic region, particularly when the transition occurs in lead V3. In addition, no reliable criteria to discriminate between a right ventricular OT (RVOT) and a left ventricular OT (LVOT) site of origin (SOO) are derived from intracardiac mapping., Methods and Results: A series of 15 patients underwent ablation because of OT ventricular arrhythmias having a V3 transition, and a septal earliest activation on the RVOT was included in the study. Electrocardiographic and mapping data were collected to analyze accuracy in predicting the RVOT versus the LVOT SOO of the ventricular arrhythmia. A 10-ms isochronal map area in the RVOT was smaller in the RVOT SOO group (1.2 [0.4-2.1] versus 3.4 [2.4-3.9] cm2, respectively; P=0.004) and had a shorter perpendicular diameter (13 [7-17] versus 28 [20-29] mm; P=0.001) and a higher longitudinal/perpendicular axis ratio (1.04 [0.95-1.11] versus 0.49 [0.44-0.57]; P=0.001). A 10-ms isochronal map area>2.3 cm2 predicted an LVOT origin with 85.7% sensitivity and 87.5% specificity, whereas a longitudinal/perpendicular axis ratio<0.8 predicted an LVOT origin with 100% sensitivity and 100% specificity. Electrocardiography-derived parameters showed lower values of sensitivity and specificity. The distal coronary sinus activation mapping did not permit distinction between RVOT and LVOT SOO., Conclusions: The 10-ms isochronal map area and the longitudinal/perpendicular axis ratio accurately predict the RVOT versus the LVOT SOO in patients with OT ventricular arrhythmias, a V3 transition, and a septal earliest activation.

Introduction and Objectives: The outcomes of atrial fibrillation ablation procedures vary widely between different centers. Our objective was to analyze the results and complications of this procedure in our center and identify factors predicting the efficacy and safety of atrial fibrillation ablation., Methods: In total, 726 atrial fibrillation ablation procedures were performed in our center between 2002 and 2009. Beginning in January 2008, a protocol for anticoagulation and conscious sedation was systematically applied. Outcomes and complications could therefore be compared in 2 well-differentiated groups: group A included 419 procedures performed prior to 2008 and group B included 307 procedures completed after 2008 using the new protocol., Results: During an average follow-up of 8.7 months, 60.9% of patients were arrhythmia-free after one or repeat procedures. After only 1 procedure, the success rate was 41% and significantly higher in group B (51.6% vs 35.2% in group A; P=.001). There were 31 major complications (4.2%), 26 in group A (6.2%) and 5 in group B (1.6%) (P=.002). The implementation of the new protocol was an independent predictor of the absence of complications (odds ratio=0.406; 95% confidence interval, 0.214-0.769; P<.006)., Conclusions: Systematic application of an anticoagulation and conscious sedation protocol is associated with improved results and fewer complications of atrial fibrillation ablation. Factors not evaluated in the present study, such as operator experience and ongoing improvements in atrial fibrillation ablation technology, could have influenced these findings., (Copyright © 2011 Sociedad Española de Cardiología. Published by Elsevier Espana. All rights reserved.)

Background: Ventricular tachycardia (VT) ablation in patients with arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) has a low success rate. A more extensive epicardial (Epi) arrhythmogenic substrate could explain the low efficacy. We report the results of combined endocardial (Endo) and Epi VT ablation and conducting channel (CC) elimination., Methods and Results: Eleven consecutive patients with ARVD/C were included in the study. A high-density 3D Endo (321±93 sites mapped) and Epi (302±158 sites mapped) electroanatomical voltage map was obtained during sinus rhythm to define scar areas (<1.5 mV) and CCs inside the scars, between scars, or between the tricuspid annulus and a scar. The end point of the ablation procedure was the elimination of all identified CCs (scar dechanneling) and the abolition of all inducible VTs. The mean procedure and fluoroscopy time were 177±63 minutes and 20±8 minutes, respectively. Epi scar area was larger in all cases (26±18 versus 94±45 cm(2), P<0.01). The combined Endo and Epi VT ablation eliminated all clinical and induced VTs, and the addition of scar dechanneling resulted in noninducibility in all cases. Seven patients continued on sotalol. During a median follow-up of 11 months (6-24 months), only 1 (9%) patient had a VT recurrence. There was a single major bleeding event that did not preclude a successful procedure., Conclusions: Combined Endo and Epi mapping reveals a wider Epi VT substrate in patients with ARVD/C with clinical VTs. As a first-line therapy, combined Endo and Epi VT ablation incorporating scar dechanneling achieves a very good short- and midterm success rate.

Introduction: Echocardiographic optimization of the VV interval may improve CRT response, but it is time-consuming and not routinely performed. The aim of this study was to compare the response to cardiac resynchronization therapy (CRT) when the interventricular pacing (VV) interval was optimized by tissue Doppler imaging (TDI) to CRT response when it was optimized following QRS width criteria., Methods and Results: The study included 156 consecutive CRT patients with severe heart failure and left bundle-branch block configuration. Atrioventricular interval was selected according to a pulsed Doppler assessment, and VV optimization was randomly assigned to echocardiography (ECHO group, n = 78) or electrocardiography (ECG group, n = 78). Optimal VV was defined for the ECHO group as producing the best LV intraventricular synchrony according to TDI displacement curves and for the ECG group as resulting in the narrowest QRS measured from the earliest deflection. At 6-month follow-up, percentage of echocardiographic responders (defined as neither death nor heart transplantation and a LV end-systolic volume reduction >10%) was higher in the ECG optimized group (50.0% vs 67.9%; P = 0.023), whereas clinical response (defined as neither death nor heart transplantation and >10% improvement in the 6-minute walking test) was similar in both groups (71.8% vs 73.1%; P = 0.858)., Conclusions: VV optimization based on QRS width obtained a higher percentage of responders in terms of LV reverse remodeling compared to the TDI method., (© 2011 Wiley Periodicals, Inc.)

Objectives: We performed noninvasive identification of post-infarction sustained monomorphic ventricular tachycardia (SMVT)-related slow conduction channels (CC) by contrast-enhanced magnetic resonance imaging (ceMRI)., Background: Conduction channels identified by voltage mapping are the critical isthmuses of most SMVT. We hypothesized that CC are formed by heterogeneous tissue (HT) within the scar that can be detected by ceMRI., Methods: We studied 18 consecutive VT patients (SMVT group) and 18 patients matched for age, sex, infarct location, and left ventricular ejection fraction (control group). We used ceMRI to quantify the infarct size and differentiate it into scar core and HT based on signal-intensity (SI) thresholds (>3 SD and 2 to 3 SD greater than remote normal myocardium, respectively). Consecutive left ventricle slices were analyzed to determine the presence of continuous corridors of HT (channels) in the scar. In the SMVT group, color-coded shells displaying ceMRI subendocardial SI were generated (3-dimensional SI mapping) and compared with endocardial voltage maps., Results: No differences were observed between the 2 groups in myocardial, necrotic, or heterogeneous mass. The HT channels were more frequently observed in the SMVT group (88%) than in the control group (33%, p < 0.001). In the SMVT group, voltage mapping identified 26 CC in 17 of 18 patients. All CC corresponded, in location and orientation, to a similar channel detected by 3-dimensional SI mapping; 15 CC were related to 15 VT critical isthmuses., Conclusions: SMVT substrate can be identified by ceMRI scar heterogeneity analysis. This information could help identify patients at risk of VT and facilitate VT ablation., (Copyright © 2011 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

For patients with Cardiovascular Implantable Electronic Devices (CIEDs), telemonitoring promises improved quality of life and safety, since events recorded by the device or observed by the patient can alert a health professional. Taking into account the latest clinical guidelines when responding to such alerts, is a topic of active research addressed by the iCARDEA project. A key technical challenge is correlating telemonitoring CIED report data in a vendor-independent format with Electronic Health Record (EHR) data collected in the hospital and Personal Health Record (PHR) data entered by the patient, in guideline-driven care processes. The iCARDEA CIED exposure service component presented in this paper employs standards specifications from ISO/IEEE 11073 (Health Informatics, Point-of-care Medical Device Communication) and HL7v2.x in the context of Integrating the Healthcare Enterprise (IHE) profiles to deliver telemonitoring CIED report data from two different CIED vendors to the adaptive care planner that implements guideline-driven care plans. Experience gained with implementation and initial component testing is discussed, while challenges and expectations for future health information standards to effectively support EHR-integrated guide-line-driven telemonitoring services are highlighted.

Arrhythmogenic right ventricular dysplasia (ARVD) is a genetically determined myocardial disease characterized by fibrofatty replacement of the right ventricular wall. Ventricular tachyarrhythmias can be seen in the early stages of the disease, which is one of the most important causes of sudden death in young healthy individuals. Radiofrequency (RF) catheter ablation is an option for the treatment of medically refractory ventricular arrhythmias and it has shown to successfully abolish recurrent ventricular tachycardias (VT) as well as reduce the frequency in defibrillator therapies. However, variable acute and long-term success rates have been reported. The current mapping and ablation techniques include activation and entrainment mapping during tolerated VT and substrate ablation using 3-dimensional electroanatomic mapping systems. This article aims at providing a comprehensive review of RF catheter ablation of ventricular arrhythmias in the context of ARVD.

Introduction and Objectives: Implantation of electrodes via the coronary sinus (CS) can be very challenging because access to the target vessel is restricted by anatomical obstacles. Consequently, prior knowledge of coronary venous anatomy is crucial. The objective of this study was to evaluate the usefulness of hyperemic venous return angiography relative to that of occlusive retrograde venography prior to cardiac resynchronization device implantation., Methods: Coronary venous anatomy was studied in 200 patients both by videoing venous coronary return, which was optimized by inducing hyperemia, and by occlusive venography. The visibility of different portions of the coronary venous system was scored., Results: Overall, sufficient anatomic information was obtained in 99.5% of patients. Visibility scores for the CS and the lateral vein of the left ventricle were slightly higher in the group studied using occlusive venography, though there was no significant difference between the two techniques. In contrast, the middle cardiac vein and the anterior interventricular vein could be visualized in greater detail using venous return angiography. There were no complications in the group studied using venous return angiography whereas dissection of the great cardiac vein occurred in three patients studied using occlusive venous angiography, though this did not prevent electrode implantation., Conclusions: With venous return angiography, it was possible to visualize accurately the venous anatomy of the lateral wall of the left ventricle and, consequently, to anticipate the level of difficulty posed by electrode implantation.

Introduction and Objectives: Provisional stenting has been shown to be effective in the treatment of bifurcated coronary lesions. The aim of this study was to evaluate changes in the geometry of the main vessel stent following side branch (SB) dilatation and kissing balloon (KB) inflation., Methods: The study involved 23 patients with a bifurcated coronary lesion. A first intravascular ultrasound (IVUS) study was performed after drug-eluting stent implantation in the main vessel. Subsequently, angioplasty of the SB was carried out, and a second IVUS was performed to evaluate its effect. Finally, KB inflation was carried out, followed by a third IVUS study of the main vessel. The cross-sectional area of the implanted stent at different points was compared in the three IVUS studies., Results: The cross-sectional area of the proximal segment of the recently implanted stent was 7.3+/-1.9 mm2 and increased to 9.6+/-2.9 mm2 after KB inflation (P< .05). Dilatation of the SB resulted in a reduction in the cross-sectional area under the SB origin from 5.9+/-1.2 mm2 initially to 5.2+/-1.2 mm2 (P< .05). After KB inflation, the cross-sectional area partially recovered (to 5.6+/-1.2 mm2)., Conclusions: After angioplasty of the SB, a reduction was observed in the cross-sectional area of the stent immediately distal to the SB origin. The area did not return to its initial value after KB inflation. However, KB inflation increased the cross-sectional area of the proximal segment of the stent and changed stent geometry.

Catheter ablation of the slow pathway for atrioventricular nodal re-entrant tachycardia (AVNRT) is not always possible due to congenital or acquired obstruction of the inferior vena cava (IVC). Although a superior access has been proposed as an alternative approach, a poor manoeuvrability and a lower stability of the ablation catheter may be potential problems. We report a case of slow pathway ablation for AVNRT in a patient with an azygos continuation using a hypoplastic but uninterrupted IVC.

The retained guidewire technique has been proposed as an alternative method for stabilizing the left ventricular lead in patients who experience repetitive intraoperative dislocation. This article concerns three patients, out of a total of 185 (1.6%) undergoing cardiac resynchronization therapy, who had to be treated using the retained guidewire technique because of demonstrable recurrent lead dislocation. Electrode parameters were all within normal limits. Although lead dislocation could not be demonstrated macroscopically, sensing and pacing parameters were found to have changed 6 months to 1 year after implantation, with a marked elevation in impedance. Laboratory analysis showed deformation and fracture of the coil electrodes as well as deterioration of the insulation coating. In conclusion, our experience shows that the retained guidewire technique should not be used because delayed electrode damage can occur.

Introduction and Objectives: Occasionally, implanting a left ventricular pacing electrode for cardiac resynchronization therapy via the coronary sinus may be complicated by the presence of anatomical structures that obstruct the access to the target vein. Our objective was to report on experience using a double-wire technique for implanting left ventricular venous leads gained at the Dr Negrín Hospital in Gran Canaria, Spain., Methods: In 20 (12%) of 170 consecutive patients (67 [9] years, 72% male) undergoing implantation of a cardiac resynchronization device, a second parallel hydrophilic guidewire had to be used during lead implantation in the target vein as implantation was impossible without using this technique., Results: Implantation using a conventional approach was impossible because there was severe tortuosity at the vessel entrance in five patients (25%), a sharp angle at the entrance to the target vein in seven (35%), a venous valve at the vessel entrance in eight (40%), and, finally, poor support for the guiding catheter in four (20%), due to the presence of either a fenestrated Thebesian valve (two patients) or a restrictive Vieussens valve (two patients) that blocked passage of the guiding catheter or electrode. In four patients (20%), there was more than one factor. In all these cases, implantation was achieved in the target vein without complications after passage of a second hydrophilic guidewire., Conclusions: The use of a second parallel guidewire (i.e., the double-wire technique) provides a safe and effective way of implanting left ventricular venous pacing electrodes in patients with anatomical complications.

The effects of chronic administration of estrogens on the lipid profile in males are not fully understood. We have studied the effect of chronic administration of estrogens on the lipid profile in a group of transsexual (TS) Canarian men who were taking estrogens and anti-androgens for a minimum of 3 years. In this cross-sectional study of cases (n=27) and controls (n=26), plasma lipid profile and selected biochemical and hormonal features were studied. TS subjects had shorter stature than controls, and, after adjusting for height and weight, we found that they had lower values of serum free testosterone (FT) and higher estradiol (E2) levels than controls. The TS group had lower total and low-density lipoprotein (LDL) cholesterol and lower apoprotein B (Apo B) levels than the control group. Biochemistry was similar in both groups. The distribution of estrogen receptor gene polymorphisms (ER-Pvu and ER-Xba) was also similar in both groups. Serum Apo B concentration was related to ER-Xba polymorphism. No other association between lipid profile and the distribution of ER-Pvu and ER-Xba was found. We conclude that the chronic administration of estrogens in men could produce an increase in serum estradiol, a decrease in free testosterone levels, and a reduction in total cholesterol, LDL-cholesterol, and Apo B levels. The ER-Xba polymorphism may influence the Apo B response to exogenous estrogen in males.

The effect of chronic administration of estrogens on bone and mineral metabolism in men is not known. We have studied the effect of chronic administration of estrogens on bone mineral metabolism in a group of transsexual (TS) Canarian men, who were taking estrogens for a minimum of 3 years. This is a cross-sectional study of cases and controls and we studied biochemical markers of bone remodeling, bone mineral density (BMD), and selected biochemical and hormonal features. TS subjects had shorter stature than controls, and after adjusting for height and weight, we found that they had lower values for serum-free testosterone and higher values for BMD, both in the lumbar spine and in femoral neck. Biochemistry, bone remodeling markers, and calcitropic hormone values were similar in both groups. Finally, the distributions of vitamin D receptor (BsmI) and estrogen receptor (ER-Pvu and ER-Xba) polymorphisms were also similar in both groups. We conclude that the chronic administration of estrogens in men may produce an increase in serum estradiol, a decrease in free testosterone levels, and an increase in BMD-both in lumbar spine and in femoral neck. We found no association between the transsexual phenotype and the distribution of vitamin D receptor (BsmI) and estrogen receptor (ER-Pvu and ER-Xba).