Implantable cardioverter defibrillators, or ICDs are devices implanted inside of the heart to prevent sudden cardiac death in patients with advanced heart failure. Studies have proven these devices to be effective for men, but new studies may indicate that they are ineffective for women. The study analyzed results from five previous ICD trials and found that women had “no reduction in all cause mortality” after being treated with the device. Women have a 70% higher risk of major adverse events after ICD implantation when compared to men. Possible explanations for these statistical disparities include the fact that “women with heart failure are more likely to die of causes other than a ventricular tachyarrhythmia which can be treated by the ICD.” Also only 8.6 of every 1,000 women who meet the criteria ICD actually receive the device, in comparison to the 32.3 of every 1,000 men with the same diagnosis. Doctors from the study are calling for more representation of women, and more variety ethnic backgrounds in clinical trials.