Predictors of appropriate implantable defibrillator therapies in patients with arrhythmogenic right ventricular dysplasia.

Background: Arrhythmogenic right ventricular dysplasia (ARVD) is an inherited cardiomyopathy characterized by ventricular arrhythmias and sudden cardiac death. The risk factors for sudden death and indications for implantable cardioverter-defibrillator (ICD) placement in patients with ARVD are not well defined.

Objectives: The purpose of this study was to determine which clinical and electrophysiologic variables best predict appropriate ICD therapies in patients with ARVD.

CT angiography is here--are we expected to see a change of angiography referral pattern?

A 52-year-old asymptomatic man, with cardiac risk factors of hypertension, Type II diabetes, hypertriglyceridemia, low HDL, obesity, and positive family history for early coronary artery disease (CAD), was referred to nuclear stress test. He exercised for 14 minutes, achieved his target heart rate, without any symptoms or ECG changes. Nuclear images were entirely normal.

Internal defibrillation with minimal skeletal muscle activation: a new paradigm toward painless defibrillation.

Background: Shock-induced pain produces substantial morbidity in recipients of implantable cardioverter-defibrillators (ICDs). This pain likely derives from activation of skeletal muscle and associated nerves in the chest and abdomen. In an effort to develop a painless defibrillation system, we designed an electrode arrangement that incorporates a conductive sock placed around the heart to confine the electric shock field to cardiac tissue.

Haptoglobin polymorphism predicts 30-day mortality and heart failure in patients with diabetes and acute myocardial infarction.

Patients with diabetes presenting with acute myocardial infarction (AMI) have an increased rate of death and heart failure. Patients with diabetes homozygous for the haptoglobin (Hp) 1 allele (Hp 1-1) develop fewer vascular complications. We tested the hypothesis that Hp type is related to the outcome of patients with diabetes presenting with AMI.

Hypoxia-inducible factor 1alpha polymorphism and coronary collaterals in patients with ischemic heart disease.

Study Objectives: Marked variability exists in coronary artery collaterals in patients with ischemic heart disease. Although multiple factors are thought to play a role in collateral development, the contribution of genetic factors is largely unknown. Hypoxia inducible factor 1 (HIF-1), a transcriptional activator that functions as a master regulator of oxygen homeostasis, is one possible genetic factor that could play an important role in modulating collateral development.

Multimodality imaging of borderline left main coronary disease using fluoroscopy, IVUS and CT coronary angiography.

A borderline left main narrowing was discovered during coronary angiography in a young asymptomatic man with positive stress test. IVUS demonstrated minimal diameter of 2.9 mm and the cross-sectional area was 11.

Safety of bivalirudin during percutaneous coronary interventions in patients with abnormal renal function.

Background: Chronic kidney disease is associated with an increased risk of ischemic and bleeding complications after percutaneous coronary intervention (PCI). Bivalirudin, a direct thrombin inhibitor, has been shown to reduce adverse bleeding events compared to unfractionated heparin in patients undergoing PCI. However, the effect of diminished renal function on the safety and efficacy of bivalirudin for PCI is unknown.

The association of subclinical coronary atherosclerosis with abdominal and total obesity in asymptomatic men.

The present study assesses and compares the association of waist circumference and body mass index with presence and severity of coronary artery calcium in asymptomatic men. The study population consisted of 451 asymptomatic men free of known coronary heart disease. The subjects were broadly divided into tertiles by waist circumference (< or =92 cm; 92.

Effect of obesity on the relationship between plasma C-reactive protein and coronary artery stenosis in patients with stable angina.

Introduction: The association between plasma C-reactive protein (CRP) and the extent of coronary artery disease (CAD) in patients with stable angina remains controversial. Obesity is strongly associated with elevated CRP levels, potentially confounding the relationship between CRP and CAD severity.

Methods And Results: We studied 830 subjects without CAD and 218 patients with CAD undergoing elective coronary angiography.

Regional differences in systolic and diastolic function in arrhythmogenic right ventricular dysplasia/cardiomyopathy using magnetic resonance imaging.

Global and regional biventricular functions were analyzed in 14 patients diagnosed with arrhythmogenic right ventricular dysplasia/cardiomyopathy using cine magnetic resonance imaging and compared with similar data from 18 age-matched controls. In this study, we report results of quantitative evaluation of biventricular global and regional function using peak ejection rate and peak filling rate as measures of systolic and diastolic function, respectively (volumetric method).

Magnetocardiogram recordings in a nonshielded environment--reproducibility and ischemia detection.

Background: Magnetocardiography (MCG) is a noninvasive technology that measures the magnetic field of the heart by superconducting quantum interference devices (SQUID) sensors. The novelty of the present system is that the sensors can be operated without electromagnetic shielding of the examination room, thus allowing the system to be easily installed in the emergency department or chest pain unit. Studies in shielded rooms, found that this imaging modality may have better sensitivity as compared to ECG in detecting ischemia.

A new method for inducing hypothermia during cardiac arrest.

Objective: It has been shown that hypothermia induced after successful resuscitation of comatose survivors of ventricular fibrillation cardiac arrest improves survival and neurologic function. Recent studies also suggest that earlier induction of hypothermia may yield even more improvement. We sought to determine if a new pump system, in addition to vigorous external chest compression, could rapidly induce hypothermia during cardiopulmonary resuscitation in a porcine model of cardiac arrest.

Stereotactic magnetic resonance guidance for anatomically targeted ablations of the fossa ovalis and the left atrium.

Introduction: Targets for radiofrequency ablation (RFA) of atrial fibrillation are increasingly being selected based on anatomic considerations. Because fluoroscopy provides only limited information about the relationship between catheter positions and cardiac structures, we evaluated whether stereotactic catheter guidance might facilitate anatomical catheter navigation and RFA to the great vessels, the fossa ovalis and the left atrium (LA).

Methods And Results: An electromagnetic catheter's position system was superimposed on three-dimensional (3D) MR images using fiducial markers.

Electrocardiographic features of arrhythmogenic right ventricular dysplasia/cardiomyopathy according to disease severity: a need to broaden diagnostic criteria.

Background: The purpose of this study was to systematically study diagnostic and prognostic electrocardiographic (ECG) characteristics of arrhythmogenic right ventricle dysplasia/cardiomyopathy (ARVD/C).

Methods And Results: The patient population included 50 patients with ARVD/C (27 males, 23 females; mean age 38+/-15 years). We also analyzed the ECG of 50 age- and gender-matched normal control subject and 28 consecutive patients who presented with right ventricular outflow tract (RVOT) tachycardia.

Modern pacemaker and implantable cardioverter/defibrillator systems can be magnetic resonance imaging safe: in vitro and in vivo assessment of safety and function at 1.5 T.

Background: MRI has unparalleled soft-tissue imaging capabilities. The presence of devices such as pacemakers and implantable cardioverter/defibrillators (ICDs), however, is historically considered a contraindication to MRI. These devices are now smaller, with less magnetic material and improved electromagnetic interference protection.

Crush stenting of bifurcational left subclavian-vertebral artery stenosis.

Left internal mammary artery (LIMA) has the best long-term patency in patients undergoing coronary artery bypass surgery. Stenosis of the proximal left subclavian artery (SA) may reduce flow to the LIMA, causing myocardial ischemia. We report a novel technique (crush stenting) for the treatment of a complex bifurcational left SA-vertebral artery (VA) stenosis in the presence of a patent LIMA bypass conduit.

Percutaneous coronary interventions in diabetic patients: is complete revascularization important?

The long-term prognosis of diabetic patients with multivessel coronary artery disease (CAD) treated by surgical or percutaneous coronary revascularization is significantly worse as compared to non-diabetics. Lower rates of complete revascularization may be one factor that influences the poor long-term outcome in the diabetic population. Our study assessed the impact of complete revascularization on the long-term prognosis in diabetic patients with CAD treated by percutaneous coronary intervention (PCI).

Implantable cardioverter-defibrillators in patients with arrhythmogenic right ventricular dysplasia/cardiomyopathy.

Objectives: The aim of this study was to assess the outcome of arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) patients treated with an implantable cardioverter-defibrillator (ICD).

Background: Arrhythmogenic right ventricular dysplasia/cardiomyopathy is associated with tachyarrhythmia and an increased risk of sudden death.

Methods: This study included 42 ARVD/C patients with ICDs (52% male, age 6 to 69 years, median 37 years) followed at our center.

Misdiagnosis of arrhythmogenic right ventricular dysplasia/cardiomyopathy.

Introduction: Diagnosis of arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) has major implications for the management of patients and their first-degree relatives. Diagnosis is based on a set of criteria proposed by the International Task Force for Cardiomyopathies. We report our experience in providing a re-evaluation for patients who previously have been diagnosed with ARVD/C.

Nikola Tesla: the man behind the magnetic field unit.

The magnetic field strength of both the magnet and gradient coils used in MR imaging equipment is measured in Tesla units, which are named for Nikola Tesla. This article presents the life and achievements of this Serbian-American inventor and researcher who discovered the rotating magnetic field, the basis of most alternating-current machinery. Nikola Tesla had 700 patents in the United States and Europe that covered every aspect of science and technology.

Vascular endothelial growth factor (VEGF) fails to improve blood flow and to promote collateralization in a diabetic mouse ischemic hindlimb model.

Background: Angiogenic therapy with vascular endothelial growth factor (VEGF) has been proposed as a treatment paradigm for patients suffering from an insufficiency of collateral vessels. Diabetes is associated with increase in the production of VEGF and therefore additional VEGF may not be beneficial. Accordingly, we sought to determine the efficacy of VEGF therapy to augment collateral formation and tissue perfusion in a diabetic mouse ischemic hindlimb model.