Bidirectional Ventricular Tachycardia in a Patient With Fulminant Myocarditis Secondary to Cardiac Sarcoidosis Mimicking Giant Cell Myocarditis.

Differentiating between sarcoidosis and giant cell myocarditis (GCM) based on clinical presentation is difficult. We present the case of a 57-year-old woman who was initially diagnosed with GCM based on endomyocardial biopsy. The patient was refractory to standard management for GCM and went on to develop bidirectional ventricular tachycardia, a finding suggestive of sarcoidosis.

Para-Hisian Pacing During Sinus Rhythm: Establishing Threshold Values to Distinguish Nodal From Septal Pathway Conduction.

Objectives: This study sought to identify minimum threshold values below which conduction over the atrioventricular (AV) node would be unexpected.

Background: Para-Hisian pacing is used to evaluate for the presence of a septal accessory pathway (AP); however, threshold values to differentiate nodal from AP conduction are unknown.

Methods: The authors performed high- and low-output para-Hisian pacing during sinus rhythm to capture the His and para-Hisian ventricular myocardium (H+V) and para-Hisian ventricular myocardium (V) alone, respectively.

An International Multicenter Evaluation of Type 5 Long QT Syndrome: A Low Penetrant Primary Arrhythmic Condition.

Background: Insight into type 5 long QT syndrome (LQT5) has been limited to case reports and small family series. Improved understanding of the clinical phenotype and genetic features associated with rare variants implicated in LQT5 was sought through an international multicenter collaboration.

Methods: Patients with either presumed autosomal dominant LQT5 (N = 229) or the recessive Type 2 Jervell and Lange-Nielsen syndrome (N = 19) were enrolled from 22 genetic arrhythmia clinics and 4 registries from 9 countries.

Novel criterion for the differential diagnosis of wide QRS complexes and wide complex tachycardia using the initial activation of QRS on leads V1 and V2: Differential diagnosis of wide QRS based on V1-V2.

Background: Many diagnostic criteria for the differential diagnosis of wide complex tachycardia (WCT) are complex and not completely accurate. Incorrect diagnosis is also related to error in applying criteria.

Objectives: To propose a novel reliable criterion for wide QRS complexes' differential diagnosis.

Implantable Cardioverter Defibrillator Implantation with or Without Defibrillation Testing.

Defibrillation testing (DFT) during implantable cardioverter-defibrillator (ICD) implantation is still considered standard of care in some, but in increasingly fewer centers. The goal is to ensure that the device system functions as intended by testing in the controlled laboratory setting. Although safe, complications can occur and DFT is associated with an increased procedural time and cost.

Prevalence of coronary artery spasm during dobutamine stress echocardiography.

The aim of this study was to assess the prevalence of coronary artery spasm during dobutamine stress echocardiography (DSE). Over a 9-year period (from November 2001 to October 2010) we reviewed all patients (n = 2,224) referred for DSE. Criteria for selection included patients > 18 years old who underwent DSE.