The advent of universal health care coverage in the United States and the use of electronic health records can make the medical record a disease surveillance tool. The objective of our study was to identify criteria that accurately categorize acute coronary and heart failure events by using electronic health record ...

Electrocardiographic artifacts may generate recordings mimicking supraventricular and ventricular tachyarrhythmias. This report describes the diagnostic challenge presented by Holter or loop recordings in two patients, one with pseudo-atrial flutter and the other with pseudo- -polymorphic ventricular tachycardia.

Compared with warfarin, dabigatran is associated with less intracranial hemorrhage, but an increased risk of myocardial infarction. To explore these phenomena, we compared their effects on thrombin generation. Thrombin generation in plasma from 10 patients taking therapeutic doses of warfarin (mean INR 2.6) was compared with that in plasma containing ...

The introduction of bare metal stents in the early 1990 and of 1st generation drug eluting stents (DES) in the early 2000 defined a new era in interventional cardiology. DES dramatically reduced instent restenosis and the need of revascularization after percutaneous coronary intervention. However, this increased efficacy came at the ...

Cardiac regeneration following myocardial infarction rests with the potential of c-kit+ cardiac progenitor cells (CPCs) to repopulate damaged myocardium. The ability of CPCs to reconstitute the heart is restricted by patient age and disease progression. Increasing CPC proliferation, telomere length, and survival will improve the ability of autologous CPCs to ...

To understand the structure-function relationship in the postinfarcted myocardium in rabbits, we induced cardiac ischemia by ligating the left circumflex coronary artery. Sham controls underwent thoracotomy only. At 7 and 30 d after ligation, cardiac MRI was conducted by using pulse-oxymetry-gated cine acquisition to provide complete phases of the heartbeat. ...

OBJECTIVE: We tested the hypothesis that short telomere length is associated with increased risk of myocardial infarction, ischemic heart disease, and early death. METHODS AND RESULTS: We measured leukocyte telomere length in 2 prospective studies of 19 838 Danish general population participants from the Copenhagen City Heart Study and the ...

OBJECTIVE: To evaluate serial data on left ventricular and myocardial reverse remodeling after restrictive mitral annuloplasty. METHODS: Thirteen patients (age, 64 ± 6 years) with functional mitral regurgitation associated with dilated cardiomyopathy (ejection fraction, ≤35%) were examined before (baseline), soon (1.7 ± 1.5 months), and more than 1 year (16 ...

Left ventricular assist device therapy as a destination therapy for end-stage heart failure has made a large leap with continuous flow devices. Continuous flow does not seem to have a detrimental effect on end-organ function, at least in the midterm. Various expected and unexpected complications have been reported associated with ...

The selection of economic end points in acute decompensated heart failure (ADHF) clinical trials requires prospectively planned evaluations that are developed in tandem with clinical end points. Integrating economic end points with concrete clinical outcomes postdischarge will provide meaningful data to evaluate a treatment's incremental value in the setting of ...

OBJECTIVE: To assess the reference values of M-mode echocardiographic measurements in healthy newborns according to body weight. METHODS: From January, 2008 to June, 2008, a total of 250 - 130 female and 120 male - term healthy newborns were included in the study. M-mode echocardiographic measurements were recorded by a ...

Background- We assessed changes in left ventricular (LV) volume and function and in regional myocardial wall stress in noninfarcted segments after restrictive mitral annuloplasty (RMA) with or without surgical ventricular restoration (SVR). Methods and Results- Thirty-nine patients with ischemic cardiomyopathy (ejection fraction ≤0.35) and severe mitral regurgitation (≥3) were studied ...

AIMS: Occurrence of late gadolinium enhancement (LGE) as assessed by cardiac magnetic resonance (CMR) imaging has been attributed to various myocardial injuries. We hypothesized that LGE is associated with left ventricular (LV) wall stress. METHODS AND RESULTS: We examined 300 patients with suspected non-ischaemic dilated cardiomyopathy. Cardiac magnetic resonance was ...

Background:  Cardiac resynchronization therapy (CRT) may be proarrhythmic in some patients. This may be due to the effect of left ventricular (LV) epicardial pacing on ventricular repolarization. The purpose of this study was to evaluate the effect of endocardial versus epicardial LV biventricular pacing on surface electrocardiogram (ECG) parameters that ...

Medical management of patients with atrial fibrillation (AF) at high risk for stroke is limited by problems of imperfect tools for assessment of thromboembolism and bleeding risks. Improved instruments, such as the CHA₂DS₂VASc and HAS-BLED risk stratification scores, have been incorporated into European practice guidelines. Until recently, the most effective ...

Transgenic rabbits expressing pore mutants of K(V)7.1 display a long QT syndrome 1 (LQT1) phenotype. Recently, NS1643 has been described to increase I(Kr).We hypothesized that NS1643 would shorten the action potential duration (APD(90)) in LQT1 rabbits. Transgenic LQT1 rabbits were compared with littermate control (LMC) rabbits. In vivo electrocardiogram studies ...

Left ventricular hypertrophy is an adaptive response to hypertension, and an independent clinical risk factor for cardiac failure, sudden death, and myocardial infarction. As regression of cardiac hypertrophy is associated with a lower likelihood of cardiovascular events, it is recognized as a target of antihypertensive therapy. This necessitates identification of ...

Myocardial tissue engineering involves the design of biomaterial scaffolds, aiming at regenerating necrotic myocardium after myocardial infarction. Biomaterials provide mechanical support to the infarct area and they can be used as vehicles for sustained and controlled local administration of cells and growth factors. Although promising results have been reported in ...

Chronic Percutaneous Epicardial Appendage Closure. Objectives: To assess the chronic safety and feasibility of percutaneous epicardial closure of the left atrial appendage (LAA) guided by electrical navigation. Background: Atrial fibrillation (AF) is associated with stroke, and LAA occlusion may be a useful nonpharmacologic strategy for stroke prevention in AF. Methods: ...

Atrial Restitution Properties. Introduction: The restitution hypothesis suggests that action potential duration (APD) restitution slope >1 predicts the development of alternans and fibrillation. This study aimed to investigate the effects of autonomic interventions on the restitution properties on the atria. Methods and Results: In 10 anesthetized open-chest dogs, multiple electrode catheters ...

The human heart can be frequently affected by an organ-limited amyloidosis called isolated atrial amyloidosis (IAA). IAA is a frequent histopathological finding in patients with long-standing atrial fibrillation (AF). The aim of this paper was to investigate the ultrastructure of cardiomyocytes and telocytes in patients with AF and IAA. Human ...

We postulated that chronic atrial fibrillation (AF) associated with mitral valve disease originated from the distended left atrium and is maintained by itself. We had performed a simple left atrial procedure for the elimination of chronic AF associated with mitral valve disease in patients from 1993 to 1998. This paper ...

the mechanism underlying spontaneous rapid superior vena cava (SVC) firing that initiates atrial fibrillation (AF) remains poorly understood. We investigated the role of the SVC-aorta-ganglionated plexus (SVC-Ao-GP) in AF initiated by rapid firing from the SVC. in 42 dogs, a circular catheter was positioned above the SVC-atrial junction. Multielectrode catheters ...

During atrial fibrillation (AF), RR interval histograms show different populations of predominant RR (pRR) intervals. These pRR intervals have been suggested to be multiples of the refractory period of the atrioventricular (AV) node or caused by the existence of a dual AV node physiology. In this study, the hypothesis that ...

Catheter ablation targeting of complex fractionated atrial electrograms (CFAEs) is one of the techniques used for atrial fibrillation (AF) ablation. The ablation of sites showing a high-frequency spectral component (HFC) during sinus rhythm, known as AF nests, has been introduced as an adjunct to conventional ablation. Known locations of some ...

Understanding pulmonary vein (PV) function before and after catheter ablation can validate the benefit of the treatment and provide mechanistic insight into atrial fibrillation (AF). This study was aimed to investigate the functional remodeling process of PVs by multi-detector computed tomography (MDCT). We assessed the dynamic function of four PVs ...

the aim of this study was to establish the electrophysiological consequences of pulmonary vein encircling ablation (PVEA) and linear left atrial roof ablation (LARA) for the atrial fibrillation (AF) substrate in an experimental model. sequential application of ablation lesions is often used in the management of AF, almost always incorporating ...

In this review, we initially covered the basic and clinical reports that provided the prevalent concepts underlying the mechanisms for atrial fibrillation (AF). The clinical evolution of catheter ablation and its eventual application to AF has also been detailed. A critique of the results based on a review of the ...

Stretch Slows Conduction in the Human Atrium. Introduction: The mechanisms by which atrial stretch favors the development of a substrate for atrial fibrillation (AF) are not fully understood. In this study, the role of stretch-induced conduction changes in the creation of a proarrhythmic substrate has been investigated by quantifying the spatial ...

Atrial fibrillation (AF) is the commonest sustained heart arrhythmia and is associated with significant morbidity and mortality, with, for example, one in five of all strokes being attributable to the condition. Dronedarone (pronounced dro-ne-da-roan) (Multaq--sanofi-aventis) is a new anti-arrhythmic drug related to the established anti-arrhythmic amiodarone. It is licensed for ...

In atrial fibrillation (AF), left ventricular (LV) systolic function positively correlates with the ratio of the preceding to prepreceding RR intervals (RRp/RRpp) and single-beat determination of LV function at a beat with equal RRp and RRpp closely estimates the average value over all cardiac cycles. The study was designed to ...

The atrial potential duration (APD) restitution has been suggested to play an important role in ventricular fibrillation; however, its role in atrial fibrillation (AF) has not been determined. This study sought to investigate the APD restitution properties in two different AF models: vagally mediated AF and 6-h rapid atrial pacing-induced ...

Radiofrequency catheter ablation of the cavotricuspid isthmus (CTI) is effective in the treatment of typical atrial flutter (AFL) and atrial fibrillation (AF). AF and AFL often coexist. However, AF often occurs following successful ablation of CTI. The aim of this study was to investigate the predictors of concomitant AF following ...

Catheter ablation is a promising therapy for atrial fibrillation (AF), but its utility in patients with left ventricular systolic dysfunction (LVSD) is uncertain. The objectives of this study were to perform a systematic review and meta-analysis of randomized and observational studies comparing the rates of recurrent AF, atrial tachycardia (AT), ...

This study aims to determine the degree and mechanisms of endo-epicardial dissociation of electrical activity during atrial fibrillation (AF) and endo-epicardial differences in atrial electrophysiology at different stages of atrial remodelling. Simultaneous high-density endo-epicardial mapping of AF was performed on left atrial free walls of goats with acute AF, after ...

Inflammation may play a significant role in the pathogenesis of atrial fibrillation (AF). To examine the roles of three systemic inflammatory markers in predicting recurrent AF. The association between the plasma concentrations of high-sensitivity C reactive protein (hsCRP), interleukin-6 (IL-6) and pentraxin-3 (PTX3) with echocardiographic parameters and with the time ...

We report on a patient with ischaemic cardiomyopathy who had received an implantable cardioverter-defibrillator for recurrent ventricular tachycardia (VT). He also developed paroxysmal atrial fibrillation (AF) which led to therapy with dronedarone. As demonstrated by the device memory, the drug not only suppressed AF but also completely suppressed VT.

Pulmonary vein (PV)-encircling ablation, which is effective in suppressing atrial fibrillation (AF), damages autonomic ganglia near the PV ostia. This study examined the effects of PV isolation (PVI) vs. peri-PV ganglionic plexus ablation (GPA) in two discrete canine AF models: ventricular tachypacing (240 bpm, 2 weeks)-induced congestive heart failure (CHF), ...

The relationship between pulmonary veins (PVs) with atrial fibrillation (AF) initiating triggers and their surrounding atrial substrate has not been elucidated. We aimed to clarify the atrial substrate properties around the PVs. Twenty-three paroxysmal AF patients were studied with the identification of PV initiating triggers. High-density mapping of the dominant ...

Defibrillation therapy for atrial fibrillation (AF) and flutter (AFl) is limited by pain induced by high-energy shocks. Thus, lowering the defibrillation energy for AFl/AF is desirable. In this study we applied low-voltage multiple-shock defibrillation therapy in a rabbit model of atrial tachyarrhythmias comparing its efficacy to single shocks and antitachycardia ...

Vagal activity is thought to influence atrial electrophysiological properties and play a role in the initiation and maintenance of atrial fibrillation (AF). We evaluated the effects of acute vagal stimulation on atrial conduction, refractoriness of atrial and pulmonary veins (PVs) and inducibility of AF. An open-chest epicardial approach was performed ...

Over a time course of months, the stability of atrial fibrillation (AF) gradually increases and the efficacy of pharmacological cardioversion declines both in humans and in animal models. Changes in fibrillatory conduction over this period largely are unexplored. Goats were instrumented with an atrial endocardial pacemaker lead and a burst ...

BACKGROUND: During persistent atrial fibrillation (AF), waves with a focal spread of activation are frequently observed. The origin of these waves and their relevance for the persistence of AF are unknown. METHODS AND RESULTS: In 24 patients with longstanding persistent AF and structural heart disease, high-density mapping of the right ...

The aim of this study was to evaluate the effectiveness of a combination of dronedarone and ranolazine in suppression of atrial fibrillation (AF). Safe and effective pharmacological management of AF remains one of the greatest unmet medical needs. The electrophysiological effects of dronedarone (10 μmol/l) and a relatively low concentration ...

This paper presents a summary of the evidence review group (ERG) report on the clinical effectiveness and cost-effectiveness of dronedarone for the treatment of atrial fibrillation (AF) or atrial flutter based upon a review of the manufacturer's submission to the National Institute for Health and Clinical Excellence (NICE) as part ...

Atrial fibrillation (AF) has been shown to be associated with reduced survival and increased ventricular arrhythmogenesis. The purpose of this study was to assess the effects of AF with adequate rate control on the electrophysiologic properties of the ventricles. We hypothesized that AF results in increased ventricular arrhythmogenic risk and ...

Low wall motion and stasis increase the likelihood of clot formation. We hypothesized that tissue Doppler indices of left atrial (LA) motion are reduced in the presence of LA thrombi and may be predictive for clot formation in patients with atrial fibrillation (AF). We did an observational study for 3 ...

Atrial fibrillation (AF) is a source of considerable morbidity and mortality. There has been compelling evidence supporting the role of renin-angiotensin system (RAS) in the genesis and perpetuation of AF through atrial remodeling, and experimental studies have validated the utilization of RAS inhibition for AF prevention. This article reviews clinical ...

Although transfusion has been linked to the development of atrial fibrillation (AF) in cardiac surgical patients, this association has not been investigated in patients with acute myocardial infarction (AMI). Evidence supports an inflammatory mechanism in the development of AF, and red cell transfusions also elicit an inflammatory response. We therefore ...

Atrial fibrillation (AF) occurs commonly in patients with acute myocardial infarction (AMI) and has been established as a marker of adverse prognosis. There are only few clinical trials that investigate differences between new-onset and chronic AF in AMI. We hypothesize that chronic AF is associated with an increased rate of ...