Cardiac Resynchronization Therapy

According to the 2013 update on heart disease statistics from American Heart Association, an estimated 5.1 million Americans ≥20 years of age have a diagnosis of heart failure. In the year 2009, heart failure was noted to be the primary cause of death in >56 000 people and contributed to death of >274 000 people. It is one of the most common causes of hospitalization in patients ≥65 years of age, and as the US population grows older, heart failure prevalence is projected to increase significantly in the near future. In about one third of heart failure patients, conduction delays cause dyssynchronous left ventricular (LV) contractions, which leads to reduction in LV performance, adverse cardiac remodeling, and also increased mortality. The prevalence of LV dyssynchrony in heart failure has been shown to increase with reduced LV ejection fraction (EF) and with increased QRS width in multiple studies. Cardiac resynchronization therapy (CRT), which was first introduced for clinical use in 1996, attempts to restore ventricular synchrony in patients with dilated cardiomyopathy and a widened QRS complex to improve the mechanical efficiency of LV contraction. Multiple studies have now documented that CRT improves quality of life, exercise capacity, symptoms of heart failure, LVEF, morbidity, and mortality in patients with moderate to severe LV dysfunction and a wide QRS complex. Several studies have also shown its benefit in mild to moderate heart failure. Since US Food and Drug Administration (FDA) approval for use in advanced heart failure in the United States in 2001, the use of CRT has steadily increased. To our knowledge, this is the first characterization of trends in utilization of CRT in the United States. Thus, using the Nationwide Inpatient Sample (NIS) database (the largest all-payer, inpatient database in the United States), we analyzed the trends of CRT implantation in the United States between 2003 and 2010. We examined various demographic parameters of patients receiving CRT implantation and potential disparities in utilization of this increasingly common