Joseph G. Akar MD, PhD

Associate Professor of Medicine (Cardiology); Academic Director of Electrophysiology; Director, Cardiac Electrophysiology Laboratory

Research Interests

Mechanisms of atrial fibrillation; Ablation of atrial fibrillation; Molecular imaging of structural remodeling; Pericardial fat and arrhythmogenesis; Effect of remote device monitoring on patient outcomes; Atrial fibrillation burden; Clinical outcomes

Current Projects

1) Non-invasive assessment of atrial remodeling using using targeted MMP molecular imaging.
2) Role of pericardial adiposity in atrial fibrillation.
3) Development of non-linear signal signal processing tools to quantify electrogram fractionation in atrial fibrillation.
4) Examination of determinants and outcomes of use of remote monitoring of cardiac devices.
5) Analysis of outcomes of the MADIT-CRT post-approval study.

Research Summary

The research focuses on developing new methods for evaluating the early causes of atrial fibrillation in order to better identify patients who are at high risk of developing this arrhythmia. We are interested in developing and using techniques that minimize patient exposure to radiation during AF ablation, and are the only center in Connecticut to offer stand-alone ultrasound guided AF-ablation that does not rely on preoperative CT scans. We have also established a robust AF program that is focused on providing comprehensive individualized care. The AF program coordinator Marianne Cosentino APRN, who along with a multidisciplinary team including representatives from pharmacy, nutrition, rehabilitation and social services, lead an AF support group for patients and their families.

Extensive Research Description

The importance of structural remodeling in the pathogenesis of atrial fibrillation (AF) is increasingly gaining attention. Specifically, the development of atrial fibrosis appears to play a major role in the promotion of AF. Thus identification of individuals at high risk of AF before the onset of irreversible fibrosis is of utmost importance. We have developed methods to non-invasively image the molecular processes leading to the development of fibrosis using targeted imaging of matrix metalloproteinases in the atrium. Using this technique we are able to non-invasively image the development of atrial structural remodeling in heart failure before the development of fibrosis. Working within the infrastructure of the Yale-New Haven Hospital/Center for Outcomes Research and Evaluation (YNHH/CORE), the overall aim of clinical research is to examine the outcomes of patients with arrhythmias. Specifically, using data from the ACC NCDR ICD database and Medicare claims, we are defining the determinants of use of remote monitoring technology in patients undergoing implantation of defibrillators, as well as the potential effect of this technology on clinical outcomes. We also have several projects examining outcomes of patients undergoing cardiac resynchronization therapy. The emphasis on quality can be translated to improved outcomes of challenging cases. The Complex Ablation Program was established in 2010 and specializes in management of refractory long-standing persistent AF, epicardial and endocardial ventricular tachycardia, and patients with structural heart disease. In patients with refractory, long-standing persistent AF, the 6-month freedom from AF was 78% in patients undergoing AF ablation

Selected Publications

  • Al-Chekakie MO, Welles CC, Metoyer R, Ibrahim A, Shapira AR, Cytron J, Santucci P, Wilber DJ, Akar JG. Pericardial Fat is Independently Associated with Human Atrial Fibrillation. J Am Coll Cardiol 2010; 56:784-788. Focus Issue on Heart Rhythm Disorders.
  • Akar JG, Jeske W, Wilber DW. Acute onset human atrial fibrillation is associated with local cardiac platelet activation and endothelial dysfunction. J Am Coll Cardiol 2008; 51:1790-1793.
  • Akar JG, Al-Chekakie MO, Fugate T, Moran L, Froloshki B, Varma N, Santucci P, Wilber DJ, Matsumura ME. Endothelial Dysfunction in Heart Failure Identifies Responders to Cardiac Resynchronization Therapy. Heart Rhythm 2008; 5:1229-1235 (Featured Article).
  • Akar JG, Al-Chekakie MO, Hai A, Brysiewicz N, Porter M, Varma N, Santucci P, Wilber D. Surface Electrocardiographic Patterns and Electrophysiological Characteristics of Atrial Flutter Following Modified Radiofrequency MAZE Procedures. J Cardiovasc Electrophysiol 2007; 18:349-355.
  • Daniels DV, Lu YY, Morton JB, Santucci PA, Akar JG, Green A, Wilber DJ. Idiopathic epicardial left ventricular tachycardia originating remote from the sinus of Valsalva: electrophysiological characteristics, catheter ablation, and identification from the 12-lead electrocardiogram. Circulation 2006; 113:1659-1666.
  • Akar JG, Everett TH, Ho RH, Craft J, Haines DE, Somlyo AP, Somlyo AV. Intracellular chloride accumulation and subcellular elemental distribution during atrial fibrillation. Circulation 2003; 107:1810-1815.

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