Long-term health-related quality of life and rhythm outcomes of catheter ablation versus antiarrhythmic drugs in patients with atrial fibrillation.

Background: Data on long-term effects of catheter ablation vs antiarrhythmic drugs (AADs) on health-related quality of life (HRQoL) and atrial fibrillation (AF) burden are limited.

Objective: The study aimed to assess long-term HRQoL and rhythm data in patients with symptomatic AF.

Methods: The 75 patients who underwent ablation and 74 receiving AADs in the Catheter Ablation compared with Pharmacological Therapy for Atrial Fibrillation (CAPTAF) trial were followed for 48 months.

Accessory pathway properties are similar in symptomatic and asymptomatic preexcitation.

Purpose: Patients with WPW syndrome have an increased mortality rate compared to the general population. Although asymptomatic preexcitation has previously been considered benign, recent studies have found that also asymptomatic patients have clinical and electrophysiological factors associated with increased risk of sudden cardiac death. This study compares the baseline electrophysiological characteristics of accessory pathways in symptomatic and asymptomatic patients with preexcitation.

Atrial fibrillation burden, episode duration and frequency in relation to quality of life in patients with implantable cardiac monitor.

Aims: To assess the relation between atrial fibrillation (AF) characteristics and health-related quality of life (QoL), and which AF characteristic had the greatest impact.

Method: The AF characteristics burden (percentage of time in AF), duration and number of AF episodes/month were obtained from implantable cardiac monitors during the 2-month run-in period in 150 patients included in the randomized CAPTAF trial comparing early ablation and antiarrhythmic drug therapy. The QoL was measured by the General Health and Vitality dimensions of the 36-Item Short-Form Health Survey.

Idiopathic ventricular fibrillation - Long term prognosis in relation to clinical findings and ECG patterns in a Swedish cohort.

Background: Idiopathic ventricular fibrillation (IVF) is a rare cause of sudden cardiac arrest which may pose therapeutic and prognostic challenges. To date, the only effective treatment for survivors of cardiac arrest is the insertion of an implantable cardioverter-defibrillator (ICD). We sought to review the long-term outcome of a Swedish cohort with IVF.

Effect of Catheter Ablation vs Antiarrhythmic Medication on Quality of Life in Patients With Atrial Fibrillation: The CAPTAF Randomized Clinical Trial.

Importance: Quality of life is not a standard primary outcome in ablation trials, even though symptoms drive the indication.

Objective: To assess quality of life with catheter ablation vs antiarrhythmic medication at 12 months in patients with atrial fibrillation.

Design, Setting, And Participants: Randomized clinical trial at 4 university hospitals in Sweden and 1 in Finland of 155 patients aged 30-70 years with more than 6 months of atrial fibrillation and treatment failure with 1 antiarrhythmic drug or β-blocker, with 4-year follow-up.

Value of the QRS-T area angle in improving the prediction of sudden cardiac death after acute coronary syndromes.

Background: Prediction of sudden cardiac death (SCD) after acute coronary syndromes (ACS) remains a challenge. Although electrophysiology measures obtained by 3-D vectorcardiography (VCG) shortly after ACS may be useful predictors of SCD, they have not been adopted into clinical practice. The main objective of our study was to assess whether the VCG-derived QRS-T area angle (between area vectors) and the QRS-T angle (between maximum vectors) have additional value beyond standard risk factors in predicting SCD after ACS.

Transient repolarization alterations dominate the initial phase of an acute anterior infarction--a vectorcardiography study.

Objective: To study effects of ischemia-reperfusion on ventricular electrophysiology in humans by three-dimensional electrocardiography.

Methods: Fifty-seven patients with first-time acute anterior ST elevation myocardial infarction were monitored from admission and >24h after symptom onset with continuous vectorcardiography (VCG; modified Frank orthogonal leads). Global ventricular depolarization and repolarization (VR) measures were compared at maximum vs.

Transient repolarization instability following the initiation of cardiac resynchronization therapy.

Aims: Cardiac resynchronization therapy (CRT) may cause changes in ventricular repolarization (VR), particularly in the initial phase of treatment. This study investigated the effect of CRT cessation and re-initiation on parameters of VR duration and heterogeneity at different paced heart rates.

Methods: Cardiac resynchronization therapy was inactivated for 2 weeks in 16 treatment responders to CRT.

Prediction of cardiovascular death and myocardial infarction by the QRS-T angle and T vector loop morphology after angioplasty in stable angina pectoris: an 8-year follow-up.

Reliable cardiovascular (CV) risk assessment by a noninvasive tool would be of great value for CV event prevention. The present study consists of 187 coronary artery disease patients with 8 years of follow-up. Eight vectorcardiographic parameters characterizing different aspects of ventricular repolarization were analyzed at baseline: (1) the ST-segment (ST-VM), (2) the T vector angles (QRS-T angle, Televation, and Tazimuth), (3) the T vector loop morphology (Tavplan and Teigenvalue), and (4) Tarea and Tpeak-end.

Ischemia-induced repolarization response in relation to the size and location of the ischemic myocardium during short-lasting coronary occlusion in humans.

Background: The ventricular repolarization (VR) response to short-lasting coronary occlusion has been characterized by 3-dimensional vectorcardiography (VCG) in humans; the T vector loop becomes distorted and more circular. The purpose of this study was to relate these changes to the size of the myocardium at risk (MAR) and its location.

Methods: Continuous VCG was applied during transient coronary occlusion in 35 elective angioplasty patients, and the size of the MAR was estimated by single-photon emission computed tomography.

Cardiac fatigue in long-distance runners is associated with ventricular repolarization abnormalities.

Background: Prolonged exercise can induce cardiac fatigue, which is characterized by biomarker release and impaired myocardial function. The impact on ventricular electrophysiology is largely unknown.

Objective: The objective of this study was to examine changes in ventricular repolarization after a 30-km cross-country race in runners aged >or=55 years.

Distorted T-vector loop and increased heart rate are associated with ventricular fibrillation in a porcine ischemia-reperfusion model.

Background: The ventricular repolarization (VR) response to short-lasting coronary occlusion has been characterized by 3-dimensional vectorcardiography during angioplasty in humans; the T-vector loop becomes distorted (increased T(avplan)) and more circular (decreased T(eigenvalue)), but these changes have not been related to ventricular arrhythmias.

Purpose: The VR response was therefore explored in a porcine ischemia-reperfusion model and compared in pigs with (n = 16) vs without (n = 17) ventricular fibrillation (VF).

Methods: Different aspects of VR were evaluated at baseline, at maximum ischemia, before reperfusion and at the subsequent ST maximum, after 1 hour of reperfusion, and before VF.

Right ventricular pacing-induced electrophysiological remodeling in the human heart and its relationship to cardiac memory.

Background: Right ventricular apical (RVA) pacing induces electrophysiological and structural remodeling. Cardiac memory (CM) evolves during the course of pacing and is readily apparent on electrocardiography (ECG) or vectorcardiography (VCG) when normal ventricular activation resumes.

Objective: This study sought to assess ventricular repolarization (VR) changes during pacing and intermittent normal ventricular conduction by ECG and VCG and to determine the temporal and conformational evolution of CM.

Ischemia induces aggravation of baseline repolarization abnormalities in left ventricular hypertrophy: a deleterious interaction.

Epidemiological studies show that left ventricular hypertrophy (LVH) and hypertension (HT) in coronary artery disease increases the risk for cardiovascular events including sudden cardiac death (SCD). According to experimental studies, myocardial hypertrophy is associated both with altered electrophysiological properties (including prolonged repolarization) and increased vulnerability to ischemia. However, human data to support a repolarization-related mechanism for the increased SCD risk has not been provided.

T vector and loop characteristics in coronary artery disease and during acute ischemia.

Objective: Three-dimensional characterization of the ventricular repolarization by the T vector and T vector loop morphology in coronary artery disease (CAD), and their response to short-term (no flow) ischemia induced by coronary occlusion during a percutaneous intervention (PCI).

Background: The risk for sudden cardiac death is increased in conditions of acute or permanently heterogeneous ventricular repolarization, for which ischemia is a risk factor.

Methods: Fifty-six CAD patients without visible collateral circulation were studied during an elective single-vessel PCI, and 10 healthy controls twice at rest.

Fecal fat, bile acid, and sterol excretion abd biliary lipid changes in jejunoileostomy patients.

Fecal fat, bile acid, and neutral sterol excretion and biliary bile acid, phospholipid, and cholesterol were studied in 36 patients 6 to 12 months after jejunoileostomy for obesity. No relationship was observed between the degree of steatorrhea and weight loss, although fecal fat rose sharply in all except 2 patients. Mean neutral sterol excretion in feces was unchanged after operation except in cholecystectomized patients.

Bile salt metabolism in tropical sprue.

Mean and peak jejunal bile salt concentrations during digestion of a standard fat meal were found to be significantly lower in six Puerto Rican patients with untreated tropical sprue, all of whom had steatorrhoea, than in six asymptomatic subjects who had normal fat absorption. Bile salt pool size and turnover time did not differ significantly in the two groups.It is suggested that bile salt concentrations may be reduced in the proximal small intestine of patients with tropical sprue as a result of excessive dilution by intestinal fluid.