Annamaria Martino

A New Electrocardiographic Marker of Sudden Death in Brugada Syndrome: The S-Wave in Lead I

BACKGROUND Risk stratification in asymptomatic patients remains by far the most important yet unresolved clinical problem in the Brugada syndrome (BrS). OBJECTIVES This study sought to analyze the usefulness of electrocardiographic parameters as markers of sudden cardiac death (SCD) in BrS. METHODS This study analyzed data from 347 consecutive patients (78.4% male; mean age 45 ± 13.1 years) with spontaneous type 1 BrS by ECG parameters but with no history of cardiac arrest (including 91.1% asymptomatic at presentation, 5.2% with a history of atrial fibrillation [AF], and 4% with a history of arrhythmic syncope). Electrocardiographic characteristics at the first clinic visit were analyzed to predict ventricular fibrillation (VF)/SCD during follow-up. RESULTS During the follow-up (48 ± 38 months), 276 (79.5%) patients remained asymptomatic, 39 (11.2%) developed syncope, and 32 (9.2%) developed VF/SCD. Patients who developed VF/SCD had a lower prevalence of SCN5A gene mutations (p = 0.009) and a higher prevalence of positive electrophysiological study results (p < 0.0001), a family history of SCD (p = 0.03), and AF (p < 0.0001). The most powerful marker for VF/SCD was a significant S-wave (≥0.1 mV and/or ≥40 ms) in lead I. In the multivariate analysis, the duration of S-wave in lead I ≥40 ms (hazard ratio: 39.1) and AF (hazard ratio: 3.7) were independent predictors of VF/SCD during follow-up. Electroanatomic mapping in 12 patients showed an endocardial activation time significantly longer in patients with an S-wave in lead I, mostly because of a significant delay in the anterolateral right ventricular outflow tract. CONCLUSIONS The presence of a wide and/or large S-wave in lead I was a powerful predictor of life-threatening ventricular arrhythmias in patients with BrS and no history of cardiac arrest at presentation. However, the prognostic value of a significant S-wave in lead I should be confirmed by larger studies and by an independent confirmation cohort of healthy subjects.

Ganglionated plexi ablation in right atrium to treat cardioinhibitory neurocardiogenic syncope

Cardioinhibitory neurocardiogenic syncope (CNS) is caused by inappropriately trigger-activated cardiac reflex which finally precipitates asystole, sinus bradycardia, or atrioventricular (AV) block [1]. Despite young patients affected by CNS have an excellent prognosis when electro-structural heart diseases are excluded [2], their quality of life may be seriously affected by recurrent episodes [2, 3]. Cardiac pacing might help to control symptoms and therefore is considered in patients aged more than 40 years old with recurrent episodes and documented cardioinhibitory response [1, 4]. In young individuals, the role of cardiac pacing is dubious due to predicted frequent device substitutions and adverse ventricular remodeling over time. Recently, radiofrequency (RF) biatrial ablation of ganglionated plexi (GP) has showed promising results in the shortand long-term treatment of reflex syncope, functional atrioventricular block, or sinus node dysfunction [5, 6]. We report the case of two patients with frequent episodes of CNSwithmarked cardioinhibitory response at head-up tilt test (HUT) who remained highly symptomatic despite common therapeutic measures. Given the young age of the patients, we decided to attempt, on the basis of previous models of atrial denervation [5], a transcatheter ablation at anatomical sites of the right atrial GP, to evaluate if vagal denervation was effective to prevent or to reduce syncope episodes, delaying as long as possible the timing for pacemaker implantation.

Echocardiographic findings in 2261 peri-pubertal athletes with or without inverted T waves at electrocardiogram

Objective T wave inversion (TWI) has been associated with cardiomyopathies. The hypothesis of this study was that TWI has relevant clinical significance in peri-pubertal athletes. Methods Consecutive male soccer players, aged 8–18 years, undergoing preparticipation screening between January 2008 and March 2009 were enrolled. Medical and family histories were collected; physical examinations, 12-lead ECGs and transthoracic echocardiogram (TTE) were performed. TWI was categorised by ECG lead (anterior (V1–V3), extended anterior (V1–V4), inferior (DII–aVF) and infero-lateral (DII–aVF/V4–V6/DI-aVL)) and by age. Results Overall, 2261 (mean age 12.4 years, 100% Caucasian) athletes were enrolled. TWI in ≥2 consecutive ECG leads was found in 136 athletes (6.0%), mostly in anterior leads (126/136, 92.6%). TWI in anterior leads was associated with TTE abnormalities in 6/126 (4.8%) athletes. TWI in extended anterior (2/136, 1.5%) and inferior (3/136, 2.2%) leads was never associated with abnormal TTE. TWI in infero-lateral leads (5/136, 3.7%) was associated with significant TTE abnormalities (3/5, 60.0%), including one hypertrophic cardiomyopathy (HCM) and two LV hypertrophies. Athletes with normal T waves had TTE abnormalities in 4.4% of cases, including one HCM with deep Q waves in infero-lateral leads. Conclusions In this broad population of peri-pubertal male athletes, TWI in anterior leads was associated with mild cardiac disease in 4.8% of cases, while TWI in infero-lateral leads revealed HCM and LV hypertrophy in 60% of cases. ECG identified all cases of HCM.

Efficacy of Ivabradine in a Case of Inappropriate Sinus Tachycardia and Ventricular Dysfunction

Ivabradine in IST.  We present a case of a 49‐year‐old man with inappropriate sinus tachycardia and ventricular dysfunction. The conventional treatment (ace‐inhibitor and beta‐blockers) was not well tolerated by the patient, so Ivabradine, a specific inhibitor of If current in the sinus node, was started. After 3 months of using this medication, we observed an improvement of ejection fraction and quality of life. (J Cardiovasc Electrophysiol, Vol. pp. 815‐817, July 2010)

Fossa ovalis radiofrequency perforation in a difficult case of conventional transseptal puncture for atrial fibrillation ablation

A 65-year-old man was referred for atrial fibrillation ablation to our center. Routine pre-procedure transthoracic and transoesophageal echocardiography and cardiac computed tomography examinations showed a normal interatrial septum and fossa ovalis anatomy. Access to left atrium was initially planned using a conventional transseptal needle puncture. During the procedure, several consecutive attempts in conjunction with intracardiac echocardiography support, failed to cross the septum. The procedure was then successfully carried out using a specifically designed radiofrequency transseptal catheter.

The anti-arrhythmic effects of n−3 PUFAs

In the past years, in vitro and animal studies have demonstrated several direct and indirect anti-arrhythmic effects of n-3 polyunsaturated fatty acids (n-3 PUFAs), at least in part mediated by anti-oxidant, anti-inflammatory and antifibrotic properties. Several epidemiological and clinical studies have been conducted to investigate the eventual benefits of fish oils in the prevention of cardiovascular diseases. The aim of this paper is to critically review current evidence on the anti-arrhythmic effects of n-3 PUFAs in the prevention of sudden cardiac death (SCD) and atrial fibrillation (AF). Published data are conflicting, but some benefits have been reported in the prevention of SCD after myocardial infarction and of AF, generally after long-course administration.

Effectiveness of a management program for outpatient clinic or remote titration of beta-blockers in CRT patients: The RESTORE study

BACKGROUND Many patients fail to receive β-blockers before cardiac resynchronization therapy defibrillator (CRT-D) implantation, or receive them at a suboptimal dose, and require optimization after implantation. We assessed the effectiveness of a structured program for β-blocker titration in CRT-D patients followed up by means of conventional in-clinic visits or remote monitoring. METHODS AND RESULTS 130 patients undergoing CRT implantation and treated according to the standard practice of the centers were included as a control group. A second group of 124 CRT-D candidates (Study Group) underwent up-titration visits every 2weeks after implantation (target dose: 10mg/day of bisoprolol or 50mg/day of carvedilol). In the Study Group, remote monitoring was undertaken in 66 patients, who received additional equipment for daily transmission of weight and blood pressure data, and scheduled titration telephone calls. In the Control Group, the maximal dose of β-blockers was being administered to 12 (9%) patients on implantation and 21 (16%) on 6-month follow-up examination (p>0.05). In the Study Group, 25 (20%) patients were receiving the maximal dose of β-blockers on implantation and 72 (58%) on follow-up examination (p<0.001). The 66 Study Group patients on remote monitoring underwent fewer in-clinic visits (p=0.034). Of these, 50 (76%) were on the maximal dose after remote up-titration (versus 38% of patients followed up conventionally, p<0.001). The decrease in left ventricular end-systolic volume was larger in the Study Group (p=0.040). CONCLUSIONS The program for β-blocker up-titration increased the number of patients reaching the target dose and improved the response to the therapy. The use of remote monitoring and daily transfer of weight and blood pressure data facilitated β-blocker titration. CLINICAL TRIAL REGISTRATION URL: http://clinicaltrials.gov/ Identifier: NCT02173028.

Omega 3 and atrial fibrillation: Where are we?

Anti-arrhythmic properties of n-3 polyunsaturated fatty acids, at least in part mediated by anti-oxidant, anti-inflammatory and anti-fibrotic power, have been widely proved. Effect of fish oil on atrial fibrillation, both in primary and in secondary prevention and after cardiac surgery, are controversial, mostly due to lack of homogeneity between studies but also due to individual variability in response to fatty acids administration. Inclusion of measurement of incorporation of fish oil into cell membranes, appears to be essential in future studies, to assess their antiarrhythmic effect.

Insidious coronary artery disease: cause, consequence, or innocent bystander for idiopathic atrial fibrillation?

Atrial fibrillation (AF) comprises a spectrum of diseases with no single mechanism adequate to comprehensively explain its variability. Although it occurs mostly in the subset of patients with diabetes mellitus, hypertension, heart failure, coronary artery, or valvular heart diseases, AF may be totally independent of these predisposing factors. ‘‘Lone AF” is characterized by the absence of any detectable heart disease or abnormality on chest x-ray film, ECG, or echocardiogram. When it occurs in the absence of any additional disease, lone AF is further termed “idiopathic.” During the last years, the concept of idiopathic AF has been reconsidered since the emergence of a number of epidemiologic associations, including sleep apnea syndrome, obesity, anger, high coffee or alcohol consumption, endurance sports activity, and mutations in various genes. A number of underlying pathophysiologic mechanisms also have been proposed for idiopathic AF, including increased atrial stretch, autonomic imbalance, systemic inflammation, oxidative stress, and structural and electrophysiological alterations. Unsurprisingly, atrial fibrosis and loss of muscle mass have been found in biopsy samples from lone AF patients, and isolated atrial coronary flow reserve impairment and conduction abnormalities also have been reported. These findings suggest that meticulous investigation may reveal, at least in part, the underlying etiology of apparently idiopathic AF. In this context, the study by Weijs et al in this issue of HeartRhythm is of great interest. This is a case-control study of a relatively young population (mean age 55 10 years) of 115 paroxysmal idiopathic AF patients (71% male) versus 275 age-, sexand PROCAM risk score–matched sinus rhythm (SR) controls. Some differences between groups can be individuated. AF patients had slightly lower high-density lipoprotein and fasting blood glucose levels than did SR controls, together with lower percentages of smoking and family history of coronary artery disease (CAD). Left atrial volumes of AF patients were larger than those of SR controls. Moreover, AF patients consumed more vitamin K antagonists, aspirin, rate control drugs, and antiarrhythmic drugs. All patients underwent cardiac computed tomographic

Right bundle branch block and conduction disturbances in Brugada syndrome and arrhythmogenic right ventricular cardiomyopathy

Right bundle branch block is relatively frequent in the general population and is generally considered benign in healthy individuals. However, it has been associated with increased cardiovascular risk and all-cause mortality in various cohort studies. Indeed, the presence of right bundle branch block in subjects affected by cardiomyopathies or channelopathies is not rare and may conceal underlying electrocardiographic changes, thus making the diagnosis of such conditions more challenging. The purpose of this review is to analyze the prevalence and clinical significance of right bundle branch block in subjects affected by Brugada syndrome and arrhythmogenic right ventricular cardiomyopathy.