The cardioverter-defibrillators that are implanted in thousands of women may not be linked to a reduced risk of death in women with advanced heart failure, according to a research.

About 5.3 million Americans are affected by heart failure and half of them are women. Patients with heart failure are six to nine times more likely than the general population to experience a sudden death.

The cardioverter-defibrillator implantation can prevent sudden cardiac death when a patient is treated for heart failure. Several clinical trials support this theory. Some speculation still remains as far as its effectiveness in women patients is concerned.

Randomized clinical trials of implantable defibrillator therapy for heart patients were searched between 1950 and 2008 which included the data on the risk of death for female patients. Five trials were found which included 934 women.

None of these five trials showed a significant benefit of the implantation compared to other therapy in women. To confirm this, a meta-analysis was done and it was found that the cardioverter-defibrillator was not linked with decreased all-cause mortality in women.

Among patients with heart disease, women have a one-fourth risk of sudden cardiac death as men. This may be due to the other illnesses that occur in women which might become the cause of their death.

"However, on the basis of our findings it seems that a trial targeting women is needed, and a meta-analysis such as ours may be an appropriate first step to explore this hypothesis", said Hamid Ghanbari, M. D., and colleagues at Providence Hospital Heart Institute and Medical Center, Southfield, Mich.