Enter Your Email Address to Receive a
Copy of MedicExhange Member Demograhpics

New research suggests that cardiac resynchronization therapy, a proven treatment for heart failure, is underused in US hospitals and when it is employed, established guidelines are often not followed.

New research suggests that cardiac resynchronization therapy, a proven treatment for heart failure, is underused in US hospitals and when it is employed, established guidelines are often not followed.

"Studies have shown that, when used in combination with optimal medical therapy, CRT is associated with a 50 per cent reduction in hospitalization for heart failure and a 36 per cent reduction in mortality," study co-author Dr. Adrian F. Hernandez said in a statement. "We did this study to analyze if and how this new therapy is being used in US hospitals."

The results, which are based on analysis of 33,898 heart failure admissions at 228 hospitals from January 2005 to September 2007, indicate that while CRT rates varied widely among hospitals, overall 12.4 per cent of patients were discharged with this treatment. The findings are reported in the August 26th issue of Circulation.

However, Dr. Hernandez, a professor at Duke Clinical Research Institute in Durham, North Carolina, believes this rate should be much higher: "That's a small percentage when you consider that we estimate 30 per cent to 50 per cent of hospitalized patients with heart failure were eligible for CRT based on previous studies."

Compared with patients not discharged with CRT, those treated with the modality had lower ejection fractions (30 per cent vs. 38 per cent), more frequent ischemic cardiomyopathy (58 per cent vs. 45 per cent), were more likely to have a history of atrial fibrillation (38 per cent vs. 27 per cent), and had greater usage of beta-blockers and aldosterone antagonists.

Overall, 4.8 per cent of subjects with an ejection fraction of 35 per cent or less were discharged with a CRT, the report indicates.

Some patients, however, may have been overtreated with CRT. Of patients discharged with a CRT, ten per cent had an ejection fraction of greater than 35 per cent, which is not an established indication for CRT. Such patients "have not been shown in trials to benefit from the therapy," Dr. Hernandez added.

Factors associated with not using CRT included treatment in the northeast, black race, increasing ejection fraction, and increasing age, the researchers note.

"Further research is needed to understand the reasons for the variations in CRT use at the patient, physician, and hospital levels and to implement programs to improve the awareness and promotion of evidence-based use of medical devices in heart failure," the authors conclude.

Circulation 2008;118