Frequent premature ventricular beats (PVB) may induce cardiomyopathy (CM). Characteristics and prognosis factor for recovery after RF ablation remain debated. 93 patients (74% men, 58±14 yo) with dilated CM associated with frequent isolated PVB were included. A group of 75 pts undergoing ablation for symptomatic PVB without significant cardiac disease serves as the control group. EF was 38±10% and left ventricular end diastolic diameter (LVEDD) was 63±8mm. One third have various associated cardiomyopathy.PVB burden was 27±12%. PVB arose from the left ventricle in 96 pts (LVOT 61, mitral 16, apex 7, septal 12) and from the right ventricle in 61 pts (RVOT 58) and multiple in 11. Epicardial ablation in the CS was needed in 25. In multivariate analysis, lack of palpitations (OR 9.09 [3.45-33.33]), VPB number > 20000 (OR 5.40 [1.98-14.70]), left ventricular origin (OR 4.12 [1.53-11.11]), epicardial location (OR 11.00 [1.92-62.50]), VPB right inferior axis (OR 2.31 [0.85-6.27]), baseline QRS width > 100ms (OR 3.66 [1.2810.43]), VPB coupling interval > 500ms (OR 3.11 [1.14-8.55]) and polymorphic VPB (OR 10.40 [1.05-103.05]) were independantly associated with CM compared to controls (p<0.05). Over a mean follow-up of 22±20 months, 79% presented with a significant decrease of VPB (> 80% reduction). In these, EF increased (36±9 to 51±12%, p<0.0001) and LVEDD decreased (62±7 to 56±7mm, p<0.0001). Reversal of CM was defined by > 10% increase in EF. Only a VPB > 2mV (OR 19.2 [1.84-200.00], p=0.01) was independanlty associated with reversal of CM in multivariate analysis. Mechanisms leading to PVB-induced CM may involve lack of palpitations, a high VPB number, a left ventricular origin, an epicardial location, a VPB right inferior axis, a large baseline QRS duration, a long VPB coupling interval and polymorphic VPB. Reversal of CM after RF ablation may associate a high VPB amplitude and a shorter VPB coupling interval. This may help in selecting patients for RF ablation of suspected VPB-induced CM.

Very narrow QRS has been described whose prevalence and prognosis relevance in the normal population is unknown. 546 healthy men between 50 and 60 yo (group 1) and 373 similar patients with coronary artery disease (368 men, EF < 50% in 40%) (group 2) underwent signal averaged ECG allowing precise measurement of QRS duration. All cause mortality was determined after 17±3 years follow-up. Mean QRS duration was 97±13ms for group 1 and 103±16ms for group 2. 85 group 1 subjects (16%) had QRS < 85ms and 23 (4%) had QRS>120ms. 44 group 2 patients (12%) had QRS < 85ms and 44 (12%) had QRS>120ms. QRS were larger in case of lower EF, lack of previous angioplasty and multivessel disease.All cause mortality in group 1 was 10,4% (57/546): 6/85 in case of QRS<85ms (7%) and 2/23 (9%) in case of QRS >120ms (p=ns compared to normal QRS duration). HR for all-cause mortality in case of QRS < 85ms was 0,75 (95% CI 0.32-1.76, p = 0,52) and 0,86 (95% CI 0.21-3.53, p = 0,84) for QRS >120ms. All cause mortality in group 2 was 29% (109/373): 7/44 in case of QRS <85ms (16%) and 22/44 (50%) in case of QRS >120ms (p=0.002 when compared to normal QRS duration). Adjusted HR for all-cause mortality in case of QRS < 85ms was 0,65 (95% CI 0.29-1.45, p = 0,29) and 1.73 (95% CI 1.02-2.94, p = 0,05) for QRS > 120ms. All cause mortality in group 2 was 29% (109/373): 7/44 in case of QRS<85ms (16%) and 22/44 (50%) in case of QRS > 120ms (p=0.002 when compared to normal QRS duration). Adjusted HR for all-cause mortality in case of QRS < 85ms was 0,65 (95% CI 0.29-1.45, p = 0,29) and 1.73 (95% CI 1.02-2.94, p = 0,05) for QRS > 120ms. Late potentials (LP) were present in SA-ECG in 116 group 1 subjects (21%). LP were present in 100 group 2 patients (27%) and were significantly related to multivessel disease, altered EF, lack of revascularization or of angioplasty. LP were more frequently observed in case of QRS > 120ms in both groups. LP were nor related to all-cause mortality in both groups. QRS “narrower than normal” (< 85ms) can be observed in a significant porpotion of healthy males between 50 and 60 years old and in similar patients with ischemic heart disease. In opposition to QRS > 120 msec which are independantly related to a higher all-cause mortality in coronary artery disease patients, QRS <85ms were not linked to prognosis in any group.

AIMS:Patients with well-tolerated sustained monomorphic ventricular tachycardia (SMVT) and left ventricular ejection fraction (LVEF) over 30% may benefit from a primary strategy of VT ablation without immediate need for a 'back-up' implantable cardioverter-defibrillator (ICD).METHODS AND RESULTS:One hundred and sixty-six patients with structural heart disease (SHD), LVEF over 30%, and well-tolerated SMVT (no syncope) underwent primary radiofrequency ablation without ICD implantation at eight European centres. There were 139 men (84%) with mean age 62 ± 15 years and mean LVEF of 50 ± 10%. Fifty-five percent had ischaemic heart disease, 19% non-ischaemic cardiomyopathy, and 12% arrhythmogenic right ventricular cardiomyopathy. Three hundred seventy-eight similar patients were implanted with an ICD during the same period and serve as a control group. All-cause mortality was 12% (20 patients) over a mean follow-up of 32 ± 27 months. Eight patients (40%) died from non-cardiovascular causes, 8 (40%) died from non-arrhythmic cardiovascular causes, and 4 (20%) died suddenly (SD) (2.4% of the population). All-cause mortality in the control group was 12%. Twenty-seven patients (16%) had a non-fatal recurrence at a median time of 5 months, while 20 patients (12%) required an ICD, of whom 4 died (20%).CONCLUSION:Patients with well-tolerated SMVT, SHD, and LVEF > 30% undergoing primary VT ablation without a back-up ICD had a very low rate of arrhythmic death and recurrences were generally non-fatal. These data would support a randomized clinical trial comparing this approach with others incorporating implantation of an ICD as a primary strategy.

BACKGROUND Both type 1 myotonic dystrophy (MD1) and Brugada syndrome (BrS) may be complicated by conduction disturbances and sudden death. Spontaneous BrS has been observed in MD1 patients, but the prevalence of drug-induced BrS in MD1 is unknown.OBJECTIVE The purpose of this study was to prospectively assess the prevalence of type 1 ST elevation as elicited during pharmacologic challenge with Class 1C drugs in a subgroup of MD1 patients and to further establish correlations with ECG and electrophysioLogic variables and prognosis.METHODS From a group of unselected 270 MD1 patients, ajmaline or flecainide drug challenge was performed in a subgroup of 44 patients (27 men, median age 43 years) with minor depolarization/repoLarization abnormalities suggestive of possible BrS. The presence of type 1 ST elevation after drug challenge was correlated to clinical, ECG, and electrophysiologic variables.RESULTS Eight of 44 patients (18 /0) presented with BrS after drug challenge. BrS was seen more often in men (26% vs 6%, P =.09) and was related to younger age (35 vs 48 years, P =.07). BrS was not correlated to symptoms, baseline ECG, HV interval, results of signal-averaged ECG, or abnormalities on ambulatory recordings. MD1 patients with BrS had longer corrected QT intervals, greater increase in PR interval after drug challenge, and higher rate of inducible ventricular arrhythmias (62% vs 21%, P =.03). Twelve patients were implanted with a pacemaker and 5 with an implantable cardioverter-defibrillator. Significant bradycardia did not occur in any patients, and malignant ventricular arrhythmia never occurred during median 7-year follow-up (except 1 hypokalemiarelated ventricular fibrillation).CONCLUSION BrS is elicited by a Class 1 drug in 18% of MD1 patients presenting with minor depolarization/repolarization abnormalities at baseline, but the finding seems to be devoid of a prognostic role.

Introduction: Both type 1 Myotonic Dystrophy (Steinert disease) and Brugada syndrome may be complicated by conduction disturbances and sudden death. ST elevation in the right precordial leads is the hallmark of Brugada syndrome but may be seen in some myopathies. Mutations in DMPK gene in Steinert patients may lead to cytosolic accumulation of muted toxic RNA or altered alternate spicing of some RNA potentially causing sodium channel dysfunctions. The prevalence of Brugada ECG pattern in Steinert disease is unknown. Methods: We perform ajmaline challenge test (1mg/kg over 5 min) during Electrophysiological (EP) testing in a population of 44 Steinert disease patients (27 men, 41±15 years old) without ST elevation at baseline. Left ventricular EF was normal in each case. The presence of type 1 ST elevation (≥ 2 mm J elevation with coved ST and negative T wave) after ajmaline challenge was correlated to clinical, ECG and electrophysiological variables. Results: 8 patients (18%) present type 1 ST elevation in the right precordial leads after ajmaline infusion. Brugada pattern was more often seen in men: 7/27 (26%) versus 1/17 (6%) (p=0.009). Patients with negative ajmaline test presented more often with fascicular block: 13/35 (27%) versus none (p=0.03). Brugada pattern was not correlated to age, symptoms, PR interval, QRS, QT or QTc durations, HV interval (at baseline or after ajmaline), presence of intraventricular conduction disturbance, of late potentials at SA-ECG or inductibility of ventricular arrhythmias at EP study. Late potentials and inductibility rate were higher in patients with Brugada pattern although without reaching statistical significance. Nine patients were implanted with a pace maker and four with an ICD. Significant or symptomatic bradycardia did not happen in any non implanted patients, while only one patiet presented with malignant ventricular arrhythmias during the 6.3±2.6 years follw-up (torsades de pointes with hypokaliemia in an ajmaline negative patient). Conclusion: Brugada ECG pattern can be elicited by class 1 drug in 18% of Steinert disease patients and especially in men. Presence of type ST elevation under class 1 drug in Steinert disease do not seem to have some significant clinical or ECG correlations.

Frequent premature ventricular beats (PVB) may induce cardiomyopathy (CM) whose characteristics and underlying mechanisms are poorly known 38 patients (27 men, 57±16yo) with dilated CM associated with frequent isolated PVB suspected to be responsible the CM were ablated between 2005 and 2011. PVB were documented <1 year (n=11), between 1 and 5 years (n=8) and >5 years (n=10) before (unknown in 9). Ejection fraction (EF), left ventricular end-diastolic diameter (LVEDD) and NYHA class were compared before and after radio-frequency ablation. 16 pts with symptomatic PVB without CM serves as the control group Baseline EF was 39±1%, LVEDD was 61±7 mm and mean NYHA class was 1.9±0.8. PVB arose from the RV in 10 pts (RVOT in 7) and from the LV in 28 pts (LVOTt in 10 and coronary cusps in 10) Compared to the control group, daily PVB number was not different in pts with suspected VPB-induced CM (22000±12000 vs 20000±14000, p=ns), as was the presence of PVB left bundle branch pattern (24/38 vs 13/16, p=ns) and gender or age. Pts with suspected PVB-induced CM had more often right axis VPB (31/37 vs 10/16, p=0.08). History of PVB was shorter in controls. Origin of the PVB did not differ between groups RF ablation completely eliminated PVB in 26 pts (68%), partially in 4 and was inefficient in 8. During a follow up of 19±19 months, EF increased from 39±10 to 52±13% (p=0.003) while LVEDD decrease from 61±7 to 56±7 mm (p=0.002) leading to a decrease in NYHA class (1.9±0.8 to 1.4±0.6, p=0.02). Parameters related to the failure of ablation were an older age, a higher NYHA class and a LVOT location of the focus. Parameters related to the lack of reversal of CM in successful ablations, were an older age, a lower baseline EF, but not the length of PVB history. RF ablation of frequent PVB may lead to cure or significant improvement in 78% of pts with associated CM. Plausible mechanisms leading to a PVB-induced CM may associate a more longer history of PVB.

Occurrence of supraventricular tachycardia is a common cause of clinical impairment for patients implanted with CRT devices. We report the case of atrial activity oversensing by the left ventricular (LV) lead during typical flutter, which led to LV pacing inhibition. Temporary reprogramming of the LV detection from standard bipolar to extended bipolar and cavotricuspid isthmus ablation solved this problem. (PACE 2013; 36:e53–e55)

BACKGROUND Despite isolated reports of Brugada syndrome (BrS) in the inferior or lateral leads, the prevalence and prognostic value of ST elevation in the peripheral electrocardiographic (ECG) leads in patients with BrS remain poorly known. OBJECTIVE To study the prevalence, characteristics, and prognostic value of type 1 ST elevation and ST depression in the peripheral ECG leads in a large cohort of patients with BrS. METHODS ECGs from 323 patients with BrS (age 47 +/- 13 years; 257 men) with spontaneous (n = 141) or drug-induced (n = 182) type 1 ECG were retrospectively reviewed. Two hundred twenty-five (70%) patients were asymptomatic, 72 (22%) patients presented with unexplained syncope, and 26 (8%) patients presented with sudden death (12 patients) or appropriated implantable cardioverter-defibrillator therapies (14 patients) at diagnosis or over a mean follow-up of 48 +/- 34 months. RESULTS Thirty (9%) patients presented with type 1 ST elevation in at least 1 peripheral lead (22 patients in the aVR leads, 2 in the inferior leads, 5 in both aVR and inferior leads, and 1 in the aVR and VL leads). Patients with type 1 ST elevation in the peripheral leads more often had mutations in the SCN5A gene, were more often inducible, had slower heart rate, and higher 3-wave amplitude in the right precordial leads. Twenty-seven percent (8 of 30) of the patients with type 1 ST elevation in the peripheral leads experimented sudden death/appropriate implantable cardioverter-defibrillator therapy, whereas it occurred in only 6% (18 of 293) of other patients (P <.0001). In multivariate analysis, type 1 ECG in the peripheral leads was independently associated with malignant arrhythmic events (odds ratio 4.58; 95% confidence interval 1.7-12.32; P = .0025). CONCLUSIONS Type 1 ST elevation in the peripheral ECG leads can be seen in 10% of the patients with BrS and is an independent predictor for a malignant arrhythmic event.

early repolarization (ER) in Brugada or short QT syndrome is common and has been associated to a less favourable outcome. Even if apparently paradoxical, ER can also be seen in long QT (LQT) but prevalence and correlations to other variables are unknown. 12 lead ECG of 37 LQT pts (19 men, 39±21 yo) and 80 matched controls were reviewed. LQT pts were selected by a positive genetic testing (n=27) or by showing abnormal T wave and long QT interval (n=10) either spontaneously or during epinephrin infusion. ER was defined by >1 mm J point elevation in the inferior or lateral leads with notch or slurring pattern. Presence of ER was correlated to the clinical and ECG characteristics and results genetic analysis. QT was 409±53 msec in pts and 372±24 in controls (p<0.0001) (QTc 476±52 vs 392±26 msec, p<0.0001). Two LQT pts presented with resuscitated sudden death and 4 with syncope at the time of diagnosis. 14/37 LQT pts (38%) had ER compared to 17/80 (21%) controls (p=0.05). ER was more frequent in men (12/19, 63%) compared to women (2/18, 11%) (p=0.001) but was not correlated to age. Pts with ER had slower heart rate (63±10 vs 75±18 bpm, p=0.02). ER was not correlated to symptoms or cardiac events (no ER in the 2 pts with SD and in 2/4 pts with syncope). QT were longer in pts with ER (450±68 vs 397±54 msec in V2, p=0.01) but there was no correlations between ER and corrected QT intervals. ER was more often seen in pts with or without mutations although non significantly (8/27 vs 6/10, p=0.09), but there was a trend toward more frequent ER in case of HeRG mutations (6/12) than KCNQ1 or KCNJ2 mutations (2/11 and 0/4) (p=0.09). ER is very common in LQT pts and is related to the gender and to the heart rate but not to the corrected QT duration. ER does not seem to be correlated to cardiac events in this series but may be linked to some gene mutations. Further studies are needed for demonstrating additional mutations/ variants or the existence of an early transient voltage gradient due to altered kinetics in muted potassium channels with loss of function.

The Epicor system ® is based on high intensity focused ultrasound (HIFU) energy used for creating a wide circumferential linear left atrial lesion encircling both left atrial posterior wall and pulmonary veins (box lesion) and provides long-term cure in patients with atrial fibrillation undergoing heart surgery. Whether if acute complete disconnection of the box lesion is achieved by application of HIFU is unknown. bipolar pacing and detection into the box lesion was studied in 9 pts (5 men, 77 ± 18 yo) undergoing heart surgery (5 aortic valve replacement, 3 mitral valve repair or replacement and one coronary by-pass) using bipolar electrophysiological catheter and a real time telemetry (Medtronic CareLink® programmer), just after completion of the ablation process on the beating heart prior to initiation of extracorporeal circulation. Sinus rhythm was present or obtained using internal cardioversion in each before the ablation process. Entrance block was absent in 7 (1 to 1 conduction from sinus rhythm inside the box lesion), undetermined in one and present in one (dissociated slow local rhythm). Exit block was lacking in 6 (capture of the cardiac rate by pacing inside the box lesion) and present in 3 (dissociated sinus rhythm from the paced area). Acute complete block of the Epicor ® HIFU induced box lesion is lacking in the vast majority of pts despite completion of the energy deliverance according to the automated ablation process. Whether block later happens, or whether supplementary applications would increase the electrophysiological and clinical success rate is unknown.

Atrial fibrillation (AFib) progressively leads to electrical remodeling (ER) and anatomical-mechanical remodeling (AMR) whose relationships remain poorly known. ER and AMR were compared in patients undergoing percutaneous RF ablation for AFib. ER was defined by right and left appendage activation rate (RAAAR and LAAAR) as a surrogate for atrial refractory periods. AMR was approached by left atrium (LA) diameters and area and left atrial appendage (LAA) area and contractile function (mean emptying flow velocity) (LAAFV) as determined during transoesophageal and transthoracic echocardiography performed during AFib the day before or immediately before RF ablation. Mean duration between successive LAA contractions was considered as LAA mechanical rate. 40 pts with paroxysmal AFib (n=10), persistent AFib (n=25) or long-persistent AFib (n=5) were included (30 men, 64±9 yo, EF 39±14%). 63% were on amiodarone. Parameters exploring AMR were highly correlated to each other: LA area 27±7 cm2; LAA area 5.5±2 cm2; LA transv 48±14 mm; LA ant-post 58±13 mm; LAA velocity 28±13 cm/sec (p<0,05 for each comparison). Parameters exploring ER were also highly correlated: RAAAR 180±39 msec; LAAAR 175±34 msec (p<0,0001). There was no significant correlation between any ER and AR parameter. Only LAA mechanical rate (172±36 msec) was highly correlated the LAAAR (p<0,01). ER and AMR are not mutually related, atrial activation rate being not correlated to LA or LAA size and mechanical function. Thus, the mechanisms leading to AFib induced atrial remodeling may differ for anatomical-mechanical and electrophysiological aspects.

Background: T-wave alternans (TWA) is an accepted marker of risk for malignant ventricular arrhythmias, for which prognosis value has been established in different populations. Short QT syndrome (SQTS) is a very rare primary electrical disease carrying the risk of ventricular fibrillation. TWA in SQTS has not been evaluated yet.Methods: Thirteen patients with SQTS (QT = 308 +/- 16 ms, QTc = 329 +/- 10 ms, heart rate = 69 +/- 8 beats/min) underwent microvolt TWA measurement using spectral analysis. TWA testing was performed using Heartwave II (Cambridge Heart (TM), Inc., Bedford, MA, USA) during bicycle exercice and classified as negative, positive, or indeterminate according to the published standards for clinical interpretation.Results: Twelve patients were male (mean age 23 +/- 5 years). Five were asymptomatic, three presented with aborted sudden cardiac death, and five with unexplained syncope. Six patients belonged to two unrelated families, while familial cases of SQTS were present for two other patients. A familial history of sudden death (SD) was present for seven patients. Ventricular fibrillation was inducible in three patients. Four patients were implanted with an implantable cardioverter-defibrillator and one presented with polymorphic ventricular tachycardia during follow-up. TWA was negative in each but one patient (indeterminate). Maximal negative heart rate was 118 +/- 12 beats/min. Patients with previous SD displayed significant shorter QT and higher resting heart rate compared to the remaining cases.Conclusions: TWA testing is negative in 12 of 13 SQTS patients, even in the symptomatic or inducible ones. Measurement of TWA using conventional protocol and criteria for risk stratification in SQTS seems therefore useless. (PACE 2012;35:14131419)

BACKGROUND:Electrophysiological alterations in atrial fibrillation (AF) may be genetically based and may lead to changes in ventricular repolarization. Short QT syndrome is a rare channelopathy with abbreviated ventricular repolarization and a propensity for AF. AIMS:To determine if minor unrecognized forms of short QT syndrome can explain some cases of lone AF. METHODS:We prospectively compared QT intervals in 66 patients with idiopathic lone AF and 132 age- and sex-matched controls. QT intervals were measured during sinus rhythm in each of the 12 surface electrocardiogram leads and corrected using Bazett's formula (QTc). QT intervals were also corrected using other formulae. Uncorrected QT and heart rate regression lines were compared between AF patients and controls. RESULTS:AF patients presented with a slower resting heart rate (64 ± 10 beats per minute [bpm] vs 69 ± 9 bpm; P=0.0006). QTc intervals were shorter in AF patients in 11/12 electrocardiogram leads (significant in 7/12, borderline in 2/12; mean QTc 381 ± 21 ms vs 388 ± 22 ms; P=0.02). QTc intervals were also shorter in AF patients, significantly or not, using other correction formulae. For similar heart rates, uncorrected QT intervals were shorter in patients when heart rates were greater than 70 bpm and longer when heart rates were less than 60 bpm. AF patients displayed steeper QT/heart rate regression line slopes than controls (P=0.009). CONCLUSION:Heart rate is significantly slower and the rate dependence of ventricular repolarization is significantly altered in patients with lone AF compared with controls. Further study is warranted to determine if AF induces subsequent ventricular repolarization changes or if these modifications are caused by an underlying primary electrical disease.

Early repolarization pattern (ERP) has recently been associated with idiopathic ventricular fibrillation and with cardiovascular mortality in the general population. We aimed to identify electrocardiographic tools to differentiate the "malignant" form of ERP from benign ERP in a population-based study. We retrospectively assessed the prevalence of ERP by recording electrocardiograms in 1,161 southwestern French subjects 35 to 64 years old. ERP was defined by an elevation of the J point >= 1 mm in 2 consecutive leads excluding leads V-1 through V-3. We categorized ERP as notching or slurring pattern as located in inferior and/or lateral leads and measured the J-point elevation amplitude. ST segment after ERP was categorized as ascendant or horizontal/nonascendant and T waves as negative or positive. Association of ERP with all-cause and cardiovascular mortalities was assessed by adjusted Cox proportional hazard models. ERP was found in 157 subjects (13.3%). During a mean follow-up of 14.2 +/- 2 years, 77 subjects died (6.6%), of whom 24 (2.1%) died from cardiovascular causes. Subjects with ERP had an increased hazard ratios for all-cause mortality (2.45, 95% confidence interval [CI] 1.44 to 4.15, p = 0.001) and cardiovascular mortality (5.60, 95% CI 2.27 to 11.8, p = 0.001). The highest risk was found for notching ERP and ERP with a nonascendant/horizontal ST segment, yielding when associated increased hazard ratios of 3.84 (95% CI 2.14 to 6.92, p = 0.001) and 8.75 (95% CI 3.48 to 22.0, p = 0.001) for all-cause and cardiovascular mortalities, respectively. Conversely, a slurring ERP or ascendant ST segment was not associated with increased mortality. ERP localization, J-point elevation amplitude, or T-wave morphology did not distinguish benign from malignant forms of ERP. In conclusion, ERP with notching pattern and horizontal/descendant ST segments was associated with the highest risk of all-cause and cardiovascular deaths. These electrocardiographic patterns may be used for risk stratification in subjects with ERP. (C) 2012 Elsevier Inc. All rights reserved. (Am J Cardiol 2012;110:1302-1308)