Indrajit Choudhuri

New echocardiographic techniques for evaluation of left atrial mechanics

Until recently the left atrium had been subordinate to the left ventricle, but cardiologists now recognize that left atrial (LA) function is indispensable to normal circulatory performance. Transthoracic two-dimensional (2D) and Doppler echocardiography can elucidate parameters of LA function non-invasively. Yet, with the advent of 2D speckle-tracking echocardiography, we are able to detect early LA dysfunction even before structural changes occur. This is pivotal in some common disease states, such as atrial fibrillation, hypertension, and heart failure, in which LA deformation parameters can influence clinical management. However, a unique standardized technique to investigate LA deformation needs to be validated.

Cardiac Resynchronization Therapy in Patients with Challenging Anatomy Due to Venous Anomalies or Adult Congenital Heart Disease

Cardiac resynchronization therapy (CRT) has proven salutary effects in patients with congestive heart failure, systolic dysfunction, and electromechanical dyssynchrony in the setting of ischemic, nonischemic, and congenital cardiomyopathy. While CRT device implants have become routine in the adult ischemic or nonischemic cardiomyopathy populations, patients with congenital heart disease offer special challenges due to unusual anatomic variations.

Spectrum of cardiac manifestations from aconitine poisoning

Swetha P. Karturi, MD, Hjalti Gudmundsson, MD, Masood Akhtar, MD, Arshad Jahangir, MD, Indrajit Choudhuri, MD From the Gundersen-Lutheran Health, La Crosse, Wisconsin, Aurora Cardiovascular Services, Aurora Sinai/Aurora St. Luke’s Medical Centers, University of Wisconsin School of Medicine and Public Health, Milwaukee, Wisconsin, and Center for Integrative Research on Cardiovascular Aging (CIRCA), Aurora Research Institute, Aurora Health Care, Milwaukee, Wisconsin.

Implantable cardioverter defibrillators in diabetics: efficacy and safety in patients at risk of sudden cardiac death

Diabetes mellitus is a major risk factor for arrhythmogenesis and is associated with a two-fold increase in all-cause mortality and a four-fold increase in cardiovascular mortality including sudden cardiac death when compared with nondiabetics. Implantable cardioverter defibrillators (ICD) have been shown to effectively reduce arrhythmic death and all-cause mortality in patients with severe myocardial dysfunction. With a high competing risk of nonarrhythmic cardiac and noncardiac death, survival benefit of ICD in patients with diabetes mellitus could be reduced, but the subanalysis of diabetic patients in randomized clinical trials provides reassurance regarding a similar beneficial survival effect of ICD and cardiac resynchronization therapy in diabetics, as observed in the overall population with advanced heart disease. In this article, the authors highlight some of the clinical issues related to diabetes, summarize the data on the efficacy of ICD in diabetics when compared with nondiabetics and discuss concerns related to ICD implantation in patients with diabetes.

Impact of obstructive sleep apnea severity on cardiac events in patients with normal or prolonged ventricular repolarization

Background: Prolonged cardiac repolarization is associated with increased risk of ventricular arrhythmias which are aggravated by several triggering factors including excess catecholamine state and electrolyte abnormalities. We studied the impact of severity of obstructive sleep apnea (OSA) on

Identifying the third dimension in 2D fluoroscopy to create 3D cardiac maps

Three-dimensional cardiac mapping is important for optimal visualization of the heart during cardiac ablation for the treatment of certain arrhythmias. However, many hospitals and clinics worldwide cannot afford the high cost of the current mapping systems. We set out to determine if, using predefined algorithms, comparable 3D cardiac maps could be created by a new device that relies on data generated from single-plane fluoroscopy and patient recording and monitoring systems, without the need for costly equipment, infrastructure changes, or specialized catheters. The study included phantom and animal experiments to compare the prototype test device, Navik 3D, with the existing CARTO 3 System. The primary endpoint directly compared: (a) the 3D distance between the Navik 3D-simulated ablation location and the back-projected ground truth location of the pacing and mapping catheter electrode, and (b) the same distance for CARTO. The studys primary objective was considered met if the 95% confidence lower limit was greater than 0.75% for the Navik 3D-CARTO difference between the 2 distances, or less than or equal to 2 mm. Study results showed that the Navik 3D performance was equivalent to the CARTO system, and that accurate 3D cardiac maps can be created using data from equipment that already exists in all electrophysiology labs.

Iatrogenic ventricular septal defect after dual-chamber pacemaker implantation

A 70-year-old obese man with pulmonary arterial hypertension, diabetes mellitus, dyslipidaemia and a history of coronary artery disease treated with four bypass grafts was referred to our centre for chest pain associated with lightheadedness and dyspnoea after usual activity. Two-dimensional echocardiography revealed left ventricular hypertrophy and severe aortic stenosis (mean …

Clinical feasibility of exercise-based A-V interval optimization for cardiac resynchronization: a pilot study.

One‐third of eligible patients fail to respond to cardiac resynchronization therapy (CRT). Current methods to “optimize” the atrio‐ventricular (A‐V) interval are performed at rest, which may limit its efficacy during daily activities. We hypothesized that low‐intensity cardiopulmonary exercise testing (CPX) could identify the most favorable physiologic combination of specific gas exchange parameters reflecting pulmonary blood flow or cardiac output, stroke volume, and left atrial pressure to guide determination of the optimal A‐V interval.