Background: Cardiac resynchronization therapy (CRT) is a proven treatment for heart failure but approximately 30% of patients appear to not benefit from the therapy. Left ventricular (LV) endocardial (Endo) and multisite epicardial (TriV) pacing have been proposed as alternatives to traditional LV transvenous epicardial (Epi) pacing, but no study has ...

The rationale for cardiac resynchronization therapy (CRT), expectations in terms of patient benefit, patient selection for CRT, the selection of a CRT pacemaker (CRT-P) versus CRT plus implantable cardioverter defibrillator (CRT-D) platform, and studies evaluating device programming to enhance benefit from CRT are reviewed. The notion of an "optimal" left ...

BACKGROUND: How coronary distensibility contributes to stable or unstable clinical manifestations remains obscure. We postulated that the heterogeneous plaque distensibility is associated with unstable clinical presentations in patients with acute coronary syndrome (ACS). METHODS AND RESULTS: Seventeen and 19 ACS-related and -unrelated lesions, respectively, were visualized using intravascular ultrasound imaging ...

Cardiac resynchronization therapy (CRT) is an established treatment for patients with moderate-to-severe heart failure and a wide QRS complex. However, the amount of reverse remodeling and clinical improvement is highly variable and poorly predictable. The left ventricular pacing site is of critical importance for the CRT response but is often ...

BACKGROUND: Current American Heart Association guidelines recommend against the performance of elective or primary percutaneous coronary intervention (PCI) without on-site surgical backup (i.e. a class III and IIb recommendation respectively). Despite this, numerous centers have already implemented PCI programs with no on-site surgery backup (NSOS). METHODS: To evaluate the necessity ...

BACKGROUND: In patients with ischemic heart failure undergoing cardiac resynchronization therapy (CRT) the underlying myocardial substrate at the left ventricle (LV) pacing site may affect CRT response. However, the effect of delivering the pacing stimulus remote, adjacent to or over LV transmural scar tissue (TST) identified by echocardiography is still ...

Background:  Primary percutaneous coronary intervention (PCI) in patients with ST-elevation myocardial infarction (STEMI) significantly reduces mortality and morbidity, particularly when door-to-balloon (D2B) time is < 90 min. We sought to minimize preventable delays by instituting an on-site cardiology team-based approach in the emergency department (ED). Methods:  The on-site group comprised 146 consecutive ...

Percutaneous coronary interventions are performed at centers without onsite surgery, despite current guidelines discouraging this. To assess literature comparing rates of in-hospital mortality and emergency coronary artery bypass grafting surgery at centers with and without on-site surgery. A systematic search of studies published between January 1990 and May 2010 was ...

ICD Electrograms and Origin of Impulses. Introduction: The implantable cardioverter-defibrillator (ICD) electrogram (EG) is a documentation of ventricular tachycardia. We prospectively analyzed EGs from ICD electrodes located at the right ventricle apex to establish (1) ability to regionalize origin of left ventricle (LV) impulses, and (2) spatial resolution to distinguish ...

ObjectiveA meta-analysis of all randomised controlled studies that compare outcomes of transradial versus the transfemoral route to better define best practice in patients with ST elevation myocardial infarction (STEMI).DesignA Medline and Embase search was conducted using the search terms 'transradial,' 'radial', 'STEMI', 'myocardial' and 'infarction'.SettingRandomised controlled studies that compare outcomes ...

Aims The first seconds of ventricular fibrillation (VF) are well organized and can consist of just 1-2 rotating waves (rotors). New rotors are spawned when local propagation block causes wave fragmentation. We hypothesized that this process, which leads to fully developed VF, begins at a consistent anatomic site.Methods and Results ...

Pacing the left ventricle (LV) from multiple sites simultaneously may result in a better response to cardiac resynchronization therapy (CRT). We sought to assess whether multisite pacing using a quadripolar LV lead improves acute hemodynamic response (AHR) to CRT. We paced four ventricular sites simultaneously using two vectors of a ...

AimsMulti-site left ventricular (LV) pacing may be superior to single-site stimulation in correcting dyssynchrony and avoiding areas of myocardial scar. We sought to characterize myocardial scar using cardiac magnetic resonance imaging (CMR). We aimed to quantify the acute haemodynamic response to single-site and multi-site LV stimulation and to relate this ...

The influence of the autonomic nervous system (ANS) on triggering and perpetuation of atrial fibrillation (AF) is well established. Ganglionated plexi (GP) ablation achieves autonomic denervation by affecting both the parasympathetic and sympathetic components of the ANS. An anatomic approach for GP ablation at relevant atrial sites appears to be ...

OBJECTIVE: To assess the electrophysiological characteristics of the breakout site of ventricular activation using electroanatomical voltage mapping (EVM) and its relation to the optimal ablation site in idiopathic ventricular tachyarrhythmias originating from the outflow tract of the (RVOT) septum. METHODS: Twenty-eight patients with symptomatic drug-refractory premature ventricular complexes (PVCs) and/or ...

OBJECTIVE: To investigate the feasibility of determination of right ventricular outflow tract (RVOT) high septal pacing site visualized by real-time three-dimensional echocardiography (RT3DE). METHODS: The forty subjects with RVOT pacing were analysed. RT3DE determination of RVOT high septal pacing sites was compared with chest X-ray (CXR). RESULTS: RVOT septal pacing ...

ObjectiveTo examine the feasibility of a routine transradial approach (TRA) in primary percutaneous coronary intervention (PPCI) for acute ST-segment elevation myocardial infarction (STEMI).DesignA single-centre observational study with prospective data collection.SettingA high-volume interventional centre in Amsterdam, The Netherlands.PatientsProcedural data were analysed for 2209 consecutive patients presenting with STEMI without cardiogenic shock, ...

PURPOSE: This study aimed to evaluate the utility of a novel pacing guidewire in pre-implantation testing of different left ventricular (LV) sites during cardiac resynchronization therapy (CRT) procedures. METHODS: Ten consecutive patients (8 male, mean age 65.8 ± 4.9) undergoing CRT procedures were studied. Pacing threshold and R-wave sensing measured by the ...

Aims To assess the impact of pacing from different right ventricular (RV) pacing sites on left ventricular (LV) function. Chronic apical RV pacing may induce heart failure. To reduce this RV, mid-septum and outflow tract are suggested as alternative pacing sites. We therefore assessed cardiac performance during temporary RV pacing ...

Prior to the widespread adoption of intracoronary stent implantation, potential complications of percutaneous coronary intervention (PCI) necessitated the presence of backup cardiac surgery. However, as stent implantation has become the predominant form of PCI, the incidence of emergent cardiac surgery has declined exponentially. Despite this, current guidelines recommend against the ...

Objective The electrocardiographic (ECG) characteristics and mode of onset of torsade de pointes (TdP) are well described. Less is known about the site of onset of this arrhythmia. This study was conducted to determine if arrhythmias in the long QT syndrome (LQTS) have a predominant site of origin. Design A ...

Background: External pumps have been previously used to minimize edema and hemorrhage caused by coronary retroperfusion. The objective of this study was to use a pump-less approach (selective autoretroperfusion, SARP) to preserve myocardial function after acute coronary artery ligation. Methods: In five experimental pigs, the LAD artery was ligated distal ...

OBJECTIVE: The objective of this study was to quantify fetal cardiovascular parameters using spatiotemporal image correlation (STIC) and virtual organ computer-aided analysis (VOCAL). STUDY DESIGN: A cross-sectional study was performed in normal pregnancies (19-42 weeks) to evaluate ventricular volume, stroke volume (SV), cardiac output (CO), and ejection fraction (EF). The ...

Postoperative atrial fibrillation is the most common complication after cardiac surgery. A variety of postoperative atrial fibrillation risk factors have been reported, but study results have been inconsistent or contradictory, particularly in patients with preexisting atrial fibrillation. The incidence of postoperative atrial fibrillation was evaluated in a group of 10,390 ...

In this paper, we present a new method for the automatic comparison of myocardial motion patterns and the characterization of their degree of abnormality, based on a statistical atlas of motion built from a reference healthy population. Our main contribution is the computation of atlas-based indexes that quantify the abnormality ...

Heart rate reduction (HRR) is an important target in the management of patients with chronic stable angina. Most available drugs for HRR such as β-blockers have adverse effects, including on cardiac energy substrate metabolism, a well-recognized determinant of cardiac homeostasis. This study aimed at (i) testing whether HRR by ivabradine ...

A 70-year-old patient with 3-vessel coronary artery disease and a left ventricular aneurysm underwent coronary artery bypass grafting, together with a surgical anterior ventricular endocardial restoration (SAVER) procedure. Four days later, he suddenly developed recurrent sustained and nonsustained polymorphic ventricular tachycardia, preceded by monomorphic ventricular premature contractions, and did not ...

Nonselective nonsteroidal anti-inflammatory drugs and selective cyclooxygenase-2 (COX-2) inhibitors are purported to increase adverse cardiovascular events. We hypothesized that COX-2 inhibitors would alter myocardial blood flow, microvascular reactivity, oxidative stress, and prostaglandin levels. Adult Yorkshire swine were divided into 3 groups: no drug (control, n = 7), a nonselective COX ...

Atrial fibrillation is the most common arrhythmia seen in clinical practice, and novel pharmacological approaches for treatment are sought. Ranolazine (Ranexa; N-(2,6-dimethylphenyl)-2-[4-(2-hydroxy-3-[2-methoxyphenoxy]propyl)piperazin-1-yl]acetamide) is used clinically for the treatment of angina pectoris. Evidence is reviewed from both pre-clinical and clinical studies, which suggests that ranolazine also exhibits antiarrhythmic activity with growing ...

the purpose of this study was to assess the predictive accuracy of conventional cardiovascular risk factors for incident heart failure and atrial fibrillation, and the added benefit of multiple biomarkers reflecting diverse pathophysiological pathways. heart failure and atrial fibrillation are interrelated cardiac diseases associated with substantial morbidity and mortality and ...

Eur J Clin Invest 2011; 41 (3): 299-307 ABSTRACT: Background  Myolysis of atrial cardiomyocytes occurs in patients with severe mitral and tricuspid regurgitation. This morphological remodelling may involve autophagy. Methods  This study comprised 20 patients (10 with long-standing persistent atrial fibrillation and 10 with sinus rhythm) with severe mitral and ...

Tei index (myocardial performance) and cardiac biomarkers were evaluated in dogs with parvoviral enteritis (PVE). Tei index was calculated as isovolumic contraction time plus isovolumic relaxation time divided by ejection time. Myocardial and skeletal muscle damages were assessed by serum levels of cardiac troponin I (cTnI), creatine (phospho) kinase, lactate ...

Atrial fibrillation developing at the acute stage of myocardial infarction is associated with untoward clinical outcomes. The aim of this study was to determine correlations between early statin therapy and atrial fibrillation in acute myocardial infarction. Patients (3396) with sinus rhythm developing acute myocardial infarction were enrolled in the French ...

Increased atrial oxidative stress plays an important role in the pathogenesis of atrial fibrillation. A predisposition for atrial fibrillation can be produced by altering the activities of enzymes related to reactive oxygen species metabolism. Microtubule integrity is necessary for cardio-protection; microtubules are involved in many cellular processes, including enzymatic activity. ...

Atrial fibrillation is the most common clinically significant cardiac arrhythmia and is associated with markedly increased risks of cardiovascular diseases. Atrial fibrillation and hypertension often coexist and are both responsible for considerable morbidity and mortality. Aggressive treatment of hypertension, especially with a blocker of the reninangiotensin system, may postpone or ...

The present review will discuss the technical aspects of a new patent invented in 1999 which allows cryoballoon ablation, an emerging technology used for the non pharmacological treatment of paroxysmal atrial fibrillation. A general evaluation of the safety and the reliability of the technique will be given together with an ...

Atrial fibrillation is the most common arrhythmia in clinical practice. Ion channel blocking agents are often characterized by limited long-term efficacy and several side effects. In addition, ablative invasive procedures are neither easily accessible nor always efficacious. The "upstream therapy," which includes angiotensin-converting enzyme inhibitors, aldosterone receptor antagonists, statins, glucocorticoids, ...

Many studies have tried to propose risk factors for atrial fibrillation recurrence after a successful pharmacological or electrical cardioversion. Regarding the duration of atrial fibrillation before electrical cardioversion, only limited data exist. The aim of our study was to investigate the effect of atrial fibrillation duration on long-term sinus rhythm ...

Long QT eight (LQT8), otherwise known as Timothy syndrome (TS), is a genetic disorder causing hyper-activation of the L-type calcium channel Cav 1.2. This calcium load and the resultant increase in the QT interval provide the substrate for ventricular arrhythmias. We previously presented a case in a patient with TS ...

We describe a case of an individual with idiopathic ventricular fibrillation whose arrhythmias were successfully controlled with phenytoin therapy.

Atrial fibrillation is rarely encountered in children and adolescents, and these cases are usually secondary to myocardial diseases, electrical abnormalities, or scar related in postoperative congenital heart disease patients. Untreated sustained atrial fibrillation may lead to tachycardia-induced cardiomyopathy and/or systemic thromboembolization. The objective here is to describe our findings in ...

We present a case of caffeine-induced atrial fibrillation which spontaneously reverted to normal sinus rhythm. Caffeine is a methylxanthine alkaloid that can cause various supraventricular and ventricular arrhythmias. It is important to improve public awareness of the potential adverse effects of high consumption of caffeine-containing products as fatal and serious ...

We present a case of large pneumopericardium resulting from an esophageal pericardial fistula following ablation for atrial fibrillation (AF). The presentation, evaluation, and management of this specific patient, along with a review of present techniques to diagnose esophageal injury, provide a unique insight into the pathophysiology of left atrial-esophageal fistula ...

For patients with atrial fibrillation, more relaxed heart rate control is as effective as stricter control but, with fewer adverse effects.

PURPOSE: The pharmacology, pharmacokinetics, safety, clinical efficacy, and role of intravenous vernakalant hydrochloride for the rapid conversion of atrial fibrillation (AF) to normal sinus rhythm are reviewed. SUMMARY: Vernakalant, currently being evaluated by the Food and Drug Administration (FDA), for the termination of atrial fibrillation, differs in pharmacology from other ...

Sudden cardiac death from ventricular fibrillation during acute myocardial infarction is a leading cause of total and cardiovascular mortality. To our knowledge, we here report the first genome-wide association study for this trait, conducted in a set of 972 individuals with a first acute myocardial infarction, 515 of whom had ...

Atrial fibrillation is the most common arrhythmia in clinical practice. There is no difference in mortality, incidence of stroke or quality of life regardless of whether the rhythm control or rate control strategy is used. However, in certain circumstances, such as when rate control is inadequate, rhythm control is a ...

BACKGROUND: The level of atrial mechanical asynchrony may vary within the atrial fibrillation population and this may have pathophysiological relevance. OBJECTIVE: We sought to verify whether the degree of left-atrial mechanical asynchrony associated with atrial fibrillation is a predictor of arrhythmia recurrence after restoration of sinus rhythm with electrical cardioversion. ...

We present a 30-year-old male with complex and predominantly cardiovascular autonomic dysfunction. He had frequent syncopal attacks and paroxysmal atrial fibrillation (PAF). Physical, electrocardiographic, and echocardiographic findings were unremarkable. Syncopal attacks were precipitated by emotional stress, upright position, and micturition. Electrocardiograms obtained immediately after syncopal events revealed PAF with a ...

Atrial fibrillation is the most common cardiac arrhythmia responsible for one third of the hospitalizations because of cardiac rhythm disturbances. Atrial fibrillation leads to stroke, heart failure, and other causes of mortality. Warfarin, a vitamin K antagonist, is the first-line agent for the prophylaxis of stroke in patients with atrial ...