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Background: Weight-stable obese subjects have an increased risk of arrhythmias and sudden death, even in the absence of cardiac dysfunction, and the risk of sudden cardiac death (SCD) with increasing weight is seen in both genders. The mechanism of unexplained deaths in obese patients is still unclear and may be related to ventricular repolarization abnormalities. The aim of this study is to determine the effect of severe obesity on spatial and transmural ventricular repolarization and to clarify the influence of bariatric surgery with a consequent substantial weight loss on arrhythmogenic substrate in the morbidly obese population. Methods: For the study, we enrolled 100 severely obese patients; 50 age-matched non-obese healthy subjects were also recruited as controls. All subjects underwent conventional 12-lead electrocardiography for analysis of spatial and transmural ventricular repolarization assessed by corrected QT dispersion (QTcd), corrected JT dispersion (JTc-d) and transmural dispersion of repolarization, (TDR). All subjects underwent bariatric surgery and were resubmitted to electrocardiographic, biochemical and anthropometric examination 12 months postoperatively. Results: Severely obese patients had greater values in QTc-d, JTc-d and TDR than the normal-weight controls. Bariatric surgery reduced significantly the QTcd value, JTc-d value and TDR value. There was a significant correlation between decrease of heterogeneity of repolarization indexes (QTd, JTd and TDR) and bariatric surgery-induced weight loss.Conclusions: In severely obese patients, surgicallyinduced weight loss is associated with significant decrease in the heterogeneity of ventricular repolarization. The reduction of spatial (QTc-d, JTc-d) and transmural dispersion of repolarization (TDR) may be of clinical significance, by reducing the risk of potentially fatal arrhythmias in morbidly obese subjects.

Epidemiological data have shown a "demographic revolution" in our society which induced a progressive increase in the elderly population, and coronary heart disease occurs more frequently in this group of subjects. Moreover, the presence of other pathologies entails specific diagnostic and therapeutic aspects in the elderly. In acute coronary syndromes percutaneous coronary angioplasty and thrombolytic agents are ever more employed despite the higher morbidity and mortality rates in the elderly. Chronic ischemic heart disease therapy, even if not different from that in younger patients, requires careful evaluation of the risk/benefit ratio. Epidemiological data have shown a "demographic revolution" in our society which induced a progressive increase in the elderly population, and coronary heart disease occurs more frequently in this group of subjects. Moreover, the presence of other pathologies entails specific diagnostic and therapeutic aspects in the elderly. In acute coronary syndromes percutaneous coronary angioplasty and thrombolytic agents are ever more employed despite the higher morbidity and mortality rates in the elderly. Chronic ischemic heart disease therapy, even if not different from that in younger patients, requires careful evaluation of the risk/benefit ratio.

Idiopathic left ventricular tachycardia is a rare arrhythmia whose electrophysiological basis is not yet well-defined. We report a case of idiopathic left ventricular tachycardia caused by a reentrant circuit limited exclusively to the two fascicles of the left bundle branch.

We have evaluated, at baseline and during incremental atrial pacing (AP), intracardiac conduction features of 53 patients with electrocardiographic diagnosis of bifascicular or trifascicular block, free from any pharmacological treatment potentially able to affect atrioventricular (AV) conduction system properties. The patients have been subdivided in the following groups: group A (13 patients), with LBBB and a PQ intervalor = 200 msec; group B (14 patients), with RBBB, LAH with a PQ intervalor = 200 msec; group C (8 patients), with LBBB and a PQ200 msec; group D (15 patients), with RBBB, LAH and a PQ200 msec; group E (3 patients), with RBBB, LPH and a PQ200 msec. In group A, 31% presented a long AH interval (140 msec), while 85% showed an increased infra-his conduction time (HV55 msec). During AP, only 38.5% maintained a 1:1 AV conduction ratio up to 140 bpm, while 30.8% developed an infra-his Mobitz 2 2nd degree AV block. 15.4% an infrahis 2:1 2nd degree AV block, 15.4% an AV nodal Mobitz 2 2nd degree AV block. In group B, 64% and 29% exhibited respectively an AV nodal and an infrahis conduction delay. During AP, 57.1% maintained a 1:1 AV conduction ratio up to 140 bpm, 14.3% developed an AV nodal Mobitz 1 2nd degree AV block, 14.3% an infrahis Mobitz 1 2nd degree AV block, 7.1% an AV nodal 2:1 2nd degree AV block, 7.1% an infrahis Mobitz 2 2nd degree AV block. In group C, no patient manifested a prolonged AH interval, while 50% exhibited a HV55 msec. 62.5% maintained a 1:1 AV conduction ratio up to 140 bpm, 25% developed an AV nodal Mobitz 1 2nd degree AV block and 12.5% an infrahis 2:1 2nd degree AV block. In group D, no patient showed an increased AH interval and only 13% presented a HV interval exceeding 55 msec. During AP, 86.7% maintained a 1:1 AV conduction ratio up to 140 bpm, 6.6% developed an AV nodal Mobitz 1 2nd degree AV block, 6.6% an infrahis 2:1 2nd degree AV block. In group E, no patient showed a prolonged AH interval, while 2/3 (66.6%) exhibited an infrahis conduction delay. During AP, 100% developed an infrahis 2:1 2nd degree AV block. Considering all patients with LBBB (groups A+C) and with RBBB+LAH (groups B+D), no differences were found in terms of PQ, PA and AH intervals, even though, concerning patients with a long PQ (group A vs group B), AH interval resulted significantly longer in patients with RBBB+LAH (121.85 +/- 36.4 msec vs 163.29 +/- 55.96 msec, p = 0.031). Infrahis conduction, independently from the measurement adopted (HVI interval: from the beginning of the His to the onset of the ventricular electrogram recorded at the His region; HV2 interval: from the beginning of the His to the onset of the surface QRS), resulted more compromised in patients with LBBB than in patients with RBBB+LAH (HVI: 75.24 +/- 40.23 msec vs 50.79 +/- 25.16 msec, p = 0.011; HV2: 77.24 +/- 38.12 msec vs 53.92 +/- 29.3 msec, p = 0.015). Such a difference became even more significant when comparing the percentage of patients with a prolonged HV interval (average value55 msec) in the above mentioned groups: 71.4% in case of LBBB, 20.7% in case of RBBB+LAH (p0.001). Regarding intraventricular conduction (IV), no statistically significant differences were found. In patients with RBBB+LAH, IV was not related to infrahis conduction time and PQ interval appeared more related to AH (r = 0.838, p0.001) than to HV (PQ-HV1: r = 0.381, p = 0.041, PQ-HV2: r = 0.474, p = 0.009). Conversely, in patients with LBBB infrahis and IV conduction appeared linearly related (HVI-V: r = 0.416, p = 0.06; HV2-V: r = 0.445, p = 0.043). As for PQ interval, it resulted more closely related to infrahis conduction (PQ-HVI: r = 0.626, p = 0.002; PQ-HV2: r = 0.674, p0.001), than to AH (r = 0.533, p = 0.013). In conclusion, infrahis conduction resulted more impaired in patients with LBBB. In this group, differently from patients with RBBB+LAH, infrahis conduction seems to affect the degree of IV conduction delay. (ABST

Antiarrhythmic drugs are known to affect depolarization and repolarization time in a different fashion. The aim of the present study was to compare the effects of sotalol, flecainide and propafenone on some common (mean QT and QTc, mean JT and JTc), or uncommon (QTc dispersion, T-peak to T-end interval-Tp-Te) electrocardiographic parameters in order to evaluate the effects of these antiarrhythmic drugs on repolarization time. QTc dispersion, defined as the difference between maximum and minimum QTc calculated from the standard 12 ECG leads, and the average Tp-Te interval, reflect regional variation in ventricular repolarization. We have analyzed retrospectively the standard 12-lead electrocardiograms of 28 patients (15 females and 13 males, age 36.11 +/- 16 years, range 11-67 years), recorded in the free-drug state and at the steady state after oral treatment with sotalol (160 mg/ die), flecainide (200 mg/die) and propafenone (450 mg/die). These drugs were prescribed, separately, for the treatment of patients with supraventricular tachycardia without underlying structural heart disease. Sotalol treatment prolongs ventricular repolarization times (QT, p = 0.0001; JT, p = 0.0001 and JTc, p = 0.0001) in an homogeneous fashion, as showed by the significant decrease in QTc dispersion (p = 0.026) and Tp-Te interval (p = 0.011). On the contrary, flecainide treatment is associated with an increase in QTc dispersion (p = 0.039) and Tp-Te interval (p = 0.0001), mean QT (p = 0.0001), QTc (p = 0.0001) and QRS (p = 0.0001), with no significant changes in JT and JTc (NS). Propafenone treatment does not affect repolarization time indexes, affecting only depolarization time as expressed by an increase in QRS (p = 0.046).

Objectives The aim of the study was to compare the diagnostic yield and the costs of implantable loop recorder (ILR) with those of the conventional strategy in patients with unexplained palpitations. Background In patients with unexplained palpitations, especially in those with infrequent symptoms, the conventional strat-egy, including short-term ambulatory electrocardiogram (ECG) monitoring and electrophysiological study, some-times fails to establish a diagnosis. Methods We studied 50 patients with infrequent (*1 episode/month), sustained (*1 min) palpitations. Before enroll-ment, patients had a negative initial evaluation, including history, physical examination, and ECG. Patients were randomized either to conventional strategy (24-h Holter recording, a 4-week period of ambulatory ECG monitor-ing with an external recorder, and electrophysiological study) (n * 24) or to ILR implantation with 1-year moni-toring (n * 26). Hospital costs of the 2 strategies were calculated. Results A diagnosis was obtained in 5 patients in the conventional strategy group, and in 19 subjects in the ILR group (21% vs. 73%, p * 0.001). Despite the higher initial cost, the cost per diagnosis in the ILR group was lower than in the conventional strategy group (€3,056 * €363 vs. €6,768 * €6,672, p * 0.012). Conclusions In subjects without severe heart disease and with infrequent palpitations, ILR is a safe and more cost-effective diagnostic approach than conventional strategy.

BACKGROUND: Recent data have shown that obesity is an important potential risk factor for atrial fibrillation (AF). The mechanism of development of AF in obesity patients is still unclear and may be related to atrial refractoriness heterogeneity. The aim of our study was to determine the influence of bariatric surgery with a consequent substantial weight loss on P-wave dispersion in morbidly obese population. METHODS: We enrolled in this study 40 severe obese patients, and 40 age-matched non-obese healthy subjects were also recruited as controls. All subjects underwent conventional 12-lead electrocardiography for the analysis of P-wave dispersion. All subjects underwent bariatric surgery and were resubmitted to electrocardiography, biochemical, and anthropometric examination within 12 months after intervention. RESULTS: Severe obese patients had greater values in P-wave duration and dispersion than the normal weight controls. Bariatric surgery reduced significantly P-wave dispersion. There was a significant correlation between decrease of atrial refractoriness heterogeneity and bariatric-surgery-induced weight loss. CONCLUSIONS: In severe obese patients, surgically induced weight loss reduction is associated with significant decreased in P-wave dispersion. The reduction of the atrial refractoriness heterogeneity may be of clinical significance by reducing the risk of atrial fibrillation in morbidly obese subjects.

Aims In dilated cardiomyopathy (DCM), attenuation of left atrial (LA) booster pump function has been observed, and attributed both to altered LA loading conditions owing to left ventricular (LV) diastolic dysfunction and to LA involvement in the myopathic process. The aim of the present study was to detect LA systolic dysfunction in DCM using speckle-tracking two-dimensional strain echocardiography (2DSE), and to assess the effects of cardiac resynchronization therapy (CRT) on LA myocardial strain during 6 month follow-up. Methods and results A total of 90 patients (aged, 52.4+10.2 years) with either idiopathic (n = 47) or ischaemic (n = 43) DCM underwent standard Doppler echo and 2DSE analysis of atrial longitudinal strain in the basal segments of LA septum and LA lateral wall, and in LA roof. The two groups were comparable for clinical variables (NYHA class: III in 72.2%; IV in 27.8%). LV volumes, ejection fraction, stroke volume, and mitral valve effective regurgitant orifice were similar between the two groups. No significant differences were evidenced in Doppler transmitral inflow measurements. LA diameter and maximal volume were also similar between the two groups. Conversely, LA active emptying volume and fraction were both lower in patients with idiopathic DCM. Peak systolic myocardial atrial strain was significantly compromised in patients with idiopathic DCM compared with ischaemic DCM in all the analysed atrial segments (P , 0.001). At follow-up, 64 patients (71.1%) (37 idiopathic and 27 ischaemic) were responders, and 26 (28.9%) (10 idiopathic; 16 ischaemic) were non-responders to CRT (responder: decrease of LV end-systolic volume .15%). A significant improvement in LA systolic function was obtained only in patients with ischaemic DCM responders to CRT (P , 0.001). By multivariable analysis, in the overall population, it was found that ischaemic aetiology of DCM (b-cofficient = 0.62; P , 0.0001) and positive response to CRT (b-cofficient = 0.42; P , 0.01) were the only independent determinants of LA lateral wall systolic strain. Conclusions Two-dimensional strain represents a promising non-invasive technique to assess LA atrial myocardial function in patients with DCM. LA pump and reservoir function at baseline and after CRT are more depressed in idiopathic compared with ischaemic DCM patients. Future longitudinal studies are warranted to understand further the natural history of LA myocardial function, the extent of reversibility of LA dysfunction with CRT, and the possible prognostic impact of such indexes in patients with congestive heart failure.

Dabigatran is a novel target specific oral anticoagulant for stroke prevention in non valvular atrial fibrillation. Little is still known about its real-world effectiveness and safety in the italian population. Aim of our study was to evaluate the efficacy and safety of dabigatran in a large single-center cohort of "real-life" italian population with non-valvular AF and to compare the results with those obtained from the RE-LY trial and the Medicare study.We studied a prospective cohort of 2108 patients (1119 male; mean age 69.4 ± 9.4 years) who started the oral anticoagulant treatment with dabigatran 110 mg twice-daily (DAB 110; N = 1075; 51%) or 150 mg twice-daily (DAB 150; N = 1033; 49%). Follow-up data were obtained trough outpatients visits each 3-6 months for assessing the clinical status, adherence to treatment, occurrence of side effects and major cardiovascular complications.In DAB 150 group the mean age was 64.9 ± 8.8 years, 56.8% of patients was male. CHA2DS2Vasc Score was ≥ 3 in 94.3% and HAS-BLED was ≥ 3 in 59.7%. In DAB 110 group (N = 1075) the mean age was 73.9 ± 7.5 years; 49.5% of patients was male. CHA2DS2Vasc Score was ≥ 3 in 73.4% and HAS-BLED was ≥ 3 in 87.4% of DAB 110 patients. One patient taking Dabigatran 110 mg bid had ischemic stroke without significantly neurological sequelae. In both groups, no patient experienced hemorrhagic stroke during the follow-up period. 147 patients (6.9%) of MonaldiCare population reported adverse effects from treatment with dabigatran, of whom 121 patients (5.7%) discontinued therapy. We reported one case of subarachnoid hemorrhage (0.05%) in a patient with high thrombo-embolic and high hemorrhagic risk score who was taking dabigatran 150 mg bid and one case (0.05%) of bladder bleeding in a patient who was taking dabigatran 110 mg bid. No major gastrointestinal bleeding was observed in the MonaldiCare population.MonaldiCare registry showed a safety profile of both dosages of dabigatran regarding major of fatal bleeding in a "real life" single center italian population at high thromboembolic and hemorrhagic risk. The majority of MonaldiCare patients tolerated dabigatran treatment without significant side effects. The efficacy of dabigatran was demonstrated by very low prevalence of ictus/TIA, also when patients underwent electrical AF cardioversion independently of the transesophageal examination.

Objective: Atrial fibrillation (AF) is the most frequently encountered arrhythmic complication associated with coronary surgery. The aim of this paper was then to identify the clinical predictors of post-CABG AF occurrence. Methods: 150 consecutive patients were included in this study and divided into two groups according to the absence (SR group, 104 male and 22 female, age 58.4 ^ 8.8 years) or presence (AF group, 23 male and 1 female, age 65.4 ^ 6.3 years) of post-CABG AF. Forty-seven perioperative variables were considered. Results: After univariate analysis, advanced age (SR vs. AF: 58.4 ^ 8.8 vs. 65.4 ^ 6.3, P , 0:001), an increased BMI (SR vs. AF: 26.1 ^ 2.7 vs. 27.4 ^ 2.5, Pa 0:026), a prior history of paroxysmal AF (SR vs. AF: 3.2% vs. 16.7%, Pa 0:028), left atrial enlargement (SR vs. AF: 21.1% vs. 70.8%, P , 0:001) and a more severe coronary artery disease (CAD) (SR vs. AF: no. of diseased vessels: 2.42 ^ 0.7 vs. 2.91 ^ 0.3, Pa 0:001; three-vessel CAD (54.1% vs. 91.3%, Pa 0:002) were the only factors that statistically differed between the groups. Multivariate logistic regression analysis identified left atrial enlargement (P , 0:0001), a prior history of paroxysmal AF (Pa 0:007) and a more severe CAD (Pa 0:0047) to be independent correlates for AF. Conclusions: Post-CABG AF seems to require a well definite anatomical and electrical substrate that is generated by increased left atrial dimensions, a greater extension of coronary lesions and a possible electrical remodeling consequent to prior repetitive episodes of paroxysmal AF. q 1999 Published by Elsevier Science B.V. All rights reserved.

The authors present a case of coronary sinus spasm during left ventricular lead implantation for biventricular pacing relieved by direct infusion of nitroglycerin.