Facilitated Myocardial Ablation Using Heat-Sensitive Liposomes Containing Doxorubicin: A Proof-of-Concept Preclinical Study.

The authors sought to evaluate a method for improving radiofrequency (RF) lesion durability using doxorubicin encased in heat-sensitive liposomes (HSL-dox). Using a porcine model, RF ablations were performed in the right atrium after systemic infusion of either HSL-dox or saline control given immediately before mapping and ablation. Lesion geometry was measured with voltage mapping immediately postablation and after 2 weeks of survival.

Use of half-normal saline irrigant with cooled radiofrequency ablation within the great cardiac vein to ablate premature ventricular contractions arising from the left ventricular summit.

A 62-year-old man was referred to our institution for high-density, symptomatic premature ventricular contractions (PVCs) with resultant decrease in left ventricular (LV) function having failed prior ablation attempts. Successful, durable ablation of the patient's mid-myocardial PVC arising from the LV summit region was achieved through the proximal great cardiac vein with ablation depth augmented by use of half-normal saline irrigant. Though standard ablation of ventricular arrhythmias using normal saline irrigation from the coronary venous system has been well-reported, this may be of limited value in addressing mid-myocardial sites of origin.

Clinical and biophysical evaluation of variable bipolar configurations during radiofrequency ablation for treatment of ventricular arrhythmias.

Background: Bipolar radiofrequency ablation (bRFA) has been used to create larger ablation lesions and to treat refractory arrhythmias. However, little is known about optimal bRFA settings.

Objective: The purpose of this study was to evaluate various bRFA settings, including active and ground catheter tip orientation and use of variable active and ground catheters during bRFA.

Enhanced Radiofrequency Ablation With Magnetically Directed Metallic Nanoparticles.

Background: Remote heating of metal located near a radiofrequency ablation source has been previously demonstrated. Therefore, ablation of cardiac tissue treated with metallic nanoparticles may improve local radiofrequency heating and lead to larger ablation lesions. We sought to evaluate the effect of magnetic nanoparticles on tissue sensitivity to radiofrequency energy.

Incidence of Atrial Fibrillation following Alcohol Septal Ablation for Hypertrophic Cardiomyopathy.

Background: Patients with hypertrophic cardiomyopathy (HCM) are at a fourfold to sixfold higher risk of developing atrial fibrillation (AF) compared to the general population, though incidence rates among patients undergoing alcohol septal ablation (ASA) are not well characterized. The purpose of this study was to evaluate atrial fibrillation incidence following ASA.

Methods: We studied 132 consecutive HCM patients without comorbid AF that underwent 154 ASA procedures.

Incidence and predictors of late complete heart block after alcohol septal ablation treatment of hypertrophic obstructive cardiomyopathy.

Objectives: This study was designed to identify the incidence of late complete heart block (CHB) first identified at least 48 hours post alcohol septal ablation (ASA).

Background: Septal reduction with ASA is a therapeutic option for patients with symptomatic hypertrophic obstructive cardiomyopathy (HCM). CHB, resulting from the septal infarct, is a known complication with a reported incidence of 9-22%.

Measured Lead Parameters and Electrogram Sensing Over Time in Patients With Cardiac Sarcoidosis and an Implanted Cardiac-Defibrillator.

Objectives: The study sought to characterize the performance of implanted leads among a cohort of patients with cardiac sarcoidosis (CS) and implantable cardiac-defibrillators (ICDs).

Background: An ICD is indicated for some patients with CS for the prevention of sudden cardiac death. CS can lead to myocardial inflammation and scar that may interfere with lead performance.

Macrolide antibiotics and the risk of cardiac arrhythmias.

Randomized, controlled trials have demonstrated that chronic therapy with macrolide antibiotics reduces the morbidity of patients with cystic fibrosis, non-cystic fibrosis bronchiectasis, chronic obstructive pulmonary disease, and nontuberculous mycobacterial infections. Lower levels of evidence indicate that chronic macrolides are also effective in treating patients with panbronchiolitis, bronchiolitis obliterans, and rejection after lung transplant. Macrolides are known to cause torsade des pointes and other ventricular arrhythmias, and a recent observational study prompted the FDA to strengthen the Warnings and Precautions section of azithromycin drug labels.

Left ventricular systolic function following alcohol septal ablation for symptomatic hypertrophic cardiomyopathy.

Because alcohol septal ablation (ASA) for the treatment of symptomatic hypertrophic cardiomyopathy (HC) with left ventricular (LV) outflow tract (LVOT) obstruction results in a myocardial infarct of up to 10% of ventricular mass, LV systolic function could decline over time. We evaluated LV function during longitudinal follow-up in a cohort of patients who underwent ASA. We studied 145 consecutive patients with HC that underwent 167 ASA procedures from 2002 to 2011.

Ranolazine for the suppression of ventricular arrhythmia: a case series.

Background: Premature ventricular complexes (PVCs) and ventricular tachycardia (VT) are associated with persistent symptoms and ventricular dysfunction. Approved medical therapies have undesirable side effects and proarrhythmic liability. Ranolazine is a novel antianginal that preferentially blocks the late sodium current.

Effect of catheter movement and contact during application of radiofrequency energy on ablation lesion characteristics.

Background: The efficient delivery of radiofrequency (RF) energy through an endocardial ablation catheter is affected by variable tissue contact due to cardiac motion with myocardial contraction and respiration. In addition, many operators intentionally move an ablation catheter during the delivery of radiofrequency energy when targeting specific arrhythmias that require lines of conduction block such as atrial flutter and atrial fibrillation. We sought to characterize and quantify any effects of catheter movement and intermittent ablation catheter contact on lesion characteristics.

Implantable cardioverter defibrillator therapy in patients with cardiac sarcoidosis.

Unlabelled: ICD Shocks in Cardiac Sarcoidosis.

Background: An implantable cardioverter defibrillator (ICD) is indicated for some patients with cardiac sarcoidosis (CS) for prevention of sudden death. However, there are little data regarding the event rates of ICD therapies in these patients.

Synthetic opioids and arrhythmia risk: a new paradigm?

The most commonly prescribed class of medications in the United States for chronic severe pain is opioid analgesics. Due to their low cost and widespread availability, the synthetic opioids are popular choices among clinicians and patients. However, there is an increasingly recognized risk of QT prolongation with several drugs in this class, and recently propoxyphene (Darvon) was withdrawn from the market by the Food and Drug Administration (FDA) due to, in part, the risk of QT prolongation and ventricular arrhythmias Updated Epidemiological Review of Propoxyphene Safety.

Electrocardiographic characteristics in patients with pulmonary sarcoidosis indicating cardiac involvement.

Introduction: Sarcoidosis is a multisystem granulomatous disease that can affect the heart. Early identification of cardiac sarcoidosis (CS) is critical because sudden death can be the initial presentation. We sought to evaluate the potential role of the ECG for identification of cardiac involvement in a cohort of patients with biopsy-proven pulmonary sarcoidosis.