Implantable cardioverter-defibrillator programming and electrical storm: Results of the OBSERVational registry On long-term outcome of ICD patients (OBSERVO-ICD).

Background: Electrical storm (ES) is defined as 3 or more episodes of ventricular fibrillation (VF) or ventricular tachycardia (VT) within 24 hours and is associated with increased cardiac and all-cause mortality.

Objective: The purpose of this study was to test whether aggressive implantable cardioverter-defibrillator (ICD) programming can be associated with ES.

Methods: The OBSERVational registry On long-term outcome of ICD patients (OBSERVO-ICD) is a multicenter, retrospective registry enrolling all consecutive patients undergoing ICD implantation from 2010 to 2012 in 5 Italian high-volume arrhythmia centers.

Natriuretic peptides: molecular biology, pathophysiology and clinical implications for the cardiologist.

Natriuretic peptides (NPs) counter the effects of volume overload or adrenergic activation of the cardiovascular system. They are able to induce arterial vasodilatations, natriuresis and diuresis, and they reduce the activities of the renin-angiotensin-aldosterone system and the sympathetic nervous system. However, in addition to wall stress, other factors have been associated with elevated natriuretic peptide levels.

Cardiac resynchronization therapy in cardiomyopathies.

Cardiomyopathies are a heterogeneous group of diseases of the myocardium that represent a major cause of morbidity and mortality due to progressive heart failure or sudden death. Cardiac resynchronization therapy has become an essential therapeutic tool in the treatment of heart failure patients today. It is an optimal choice in patients with dilated cardiomyopathy; however, its role in the management of patients with other forms of cardiomyopathies is still under investigation.

Effect of cardiac resynchronization therapy on cardiotrophin-1 circulating levels in patients with heart failure.

Cardiotrophin-1 (CT-1) is a member of the interleukin (IL-6) family of cytokines. Plasma CT-1 levels correlate with the left ventricle mass index in patients with dilatated cardiomyopathy and congestive heart failure (CHF). The aim of this paper was to evaluate CT-1 plasma levels, before and after cardiac resynchronization therapy CRT, and to characterizeits prognostic role in patients with CHF.

Superselective cannulation of coronary sinus branch with telescopic system during left ventricular lead placement.

We present a case of a 55-year-old man with idiopathic dilated cardiomyopathy, ejection fraction (EF) of 27%, left bundle branch block with QRS duration of 160 ms, NYHA class III, and optimal medical therapy for at least 6 months who was referred to our division for cardiac resynchronization therapy (CRT) using a biventricular pacing device. During the operation, the coronary sinus branch cannulation failed using classical angioplasty guide wire techniques. The pacing lead was successfully implanted into the posterior target vein using a telescopic dual-catheter system.

Effects of global longitudinal strain and total scar burden on response to cardiac resynchronization therapy in patients with ischaemic dilated cardiomyopathy.

Aims: To evaluate whether quantification of the extent of scarred left ventricular (LV) tissue by speckle-tracking strain echo (2DSE) can predict response to cardiac resynchronization therapy (CRT) in patients with ischaemic dilated cardiomyopathy (DCM).

Methods And Results: Forty-five patients (58.3 +/- 8.

Severe obesity and P-wave dispersion: the effect of surgically induced weight loss.

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.

Different effects of cardiac resynchronization therapy on left atrial function in patients with either idiopathic or ischaemic dilated cardiomyopathy: a two-dimensional speckle strain study.

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.

Sympathovagal balance analysis in idiopathic postural orthostatic tachycardia syndrome.

The idiopathic postural tachycardia syndrome (POTS) is a complex disorder characterized by chronic orthostatic symptoms and an increase in heart rate within 10 minutes of standing on upright posture, without significant orthostatic hypotension. We describe a case of a 36 year-old patient with POTS, diagnosed by head-up tilt testing. Power spectral analysis of heart rate variability (HRV), performed during the tilt test, revealed the ratio of low and high frequency powers (LF/HF) that increased with the onset of orthostatic intolerance.

Effect of weight loss following bariatric surgery on myocardial dispersion of repolarization in morbidly obese patients.

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.

Coronary sinus spasm during left ventricular lead implantation for biventricular pacing.

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

Recurrent unexplained palpitations (RUP) study comparison of implantable loop recorder versus conventional diagnostic strategy.

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 strategy, including short-term ambulatory electrocardiogram (ECG) monitoring and electrophysiological study, sometimes fails to establish a diagnosis.

Methods: We studied 50 patients with infrequent (< or =1 episode/month), sustained (>1 min) palpitations.

Effect of dynamic myocardial dyssynchrony on mitral regurgitation during supine bicycle exercise stress echocardiography in patients with idiopathic dilated cardiomyopathy and 'narrow' QRS.

Aims: Cardiac resynchronization therapy (CRT) has become an attractive therapeutic option for patients with end-stage heart failure (HF). Currently, patients are selected for CRT on ECG and on echocardiographic criteria analysed at rest. Whether the physical effort may further increase myocardial dyssynchrony is not fully established.

Influence of biventricular pacing on myocardial dispersion of repolarization in dilated cardiomyopathy patients.

Aims: The aim of our study was to evaluate the effect of cardiac resyncronization therapy on QT dispersion (QTd), JT dispersion (JTd), and transmural dispersion of repolarization (TDR), markers of heterogeneity of ventricular repolarization in a study population with severe heart failure.

Methods And Results: Fifty patients (43 male, 7 female, age 60.2+/-3.

Heart rate variability analysis in postural orthostatic tachycardia syndrome: a case report.

The authors present a case of 36 year old male patient with idiopathic postural orthostatic tachycardia syndrome (POTS) diagnosed during head-up tilt testing. Power spectral analysis of heart rate variability (HRV) during the tilt test revealed that the ratio of low and high frequency powers (LF/HF) increased with the onset of orthostatic intolerance. This analysis confirmed in our patient a strong activation in sympathetic tone.

QT dispersion on ECG Holter monitoring and risk of ventricular arrhythmias in patients with dilated cardiomyopathy.

Background: QT dispersion (QTd) is increased in patients with dilated cardiomyopathy. Increased QTd has been associated with the risk of sudden death. We studied: a) the relation between QTd on 12-lead ECG and QTd-ECG Holter; b) the relation between QTd apex (QTda) and QTd end (QTde) on ECG Holter and the risk of ventricular arrhythmias in patients with dilated cardiomyopathy.

Biventricular pacing and heterogeneity of ventricular repolarization in heart failure patients.

Objective: The aim of our study was to evaluate the effect of cardiac resyncronization therapy (CRT) on QT dispersion (QTd), JT dispersion (JTd) and transmural dispersion of re-polarization (TDR), markers of heterogeneity of ventricular repolarization in a study population with severe heart failure.

Methods And Results: Fifty patients (43 male, 7 female, aged 60.2 ± 3.