The news is especially significant considering that statistically, heart disease is a bigger killer of women than breast cancer is. Additionally and more worryingly, this suggests that women have been taking incorrect dosages or even an unsuitable drug for their condition.
The researchers, from Germany, were writing in the latest addition of the European Heart Journal, an official publication of the European Society of Cardiology.
During their research, the scientists also found potentially life-threatening heart rhythm disorders occurred significantly more often in women, suggesting they needed closer monitoring when undergoing treatment to correct such problems.
They added that the problem was compounded by the fact that that too few women took part in such studies, meaning there was not enough data to make a clear conclusion. This may partly be because for many years, heart disease was wrongly seen as a "male" condition.
Verena Stangl, a professor of cardiology, who led the research, said in the study that it was essential that trials were designed to provide the necessary data.
"We prescribe drugs to women adapted from evidence-based data obtained from studies conducted mainly in men and we do not really know whether we help or harm the female patients," she added.
"It's unclear whether it is really linked to increased mortality among women or whether this increase is an effect only of an overdose, and therefore whether they would benefit from lower doses adapted to their weight."
The findings may not be as unusual as first thought. Gender differences, which determine the drugs efficacy, have been well documented. Differences in pharmacokinetics, pharmacodynamics, and physiology contribute to the phenomenon that women and men frequently respond differently to cardiovascular drugs.
Hormonal influences, in addition, can play an important role. For example, the menstrual cycle, menopause, and pregnancy, as a result of fluctuations in concentrations of sexual steroids, and of changes in total body water, can be associated with gender-specific differences in the plasma levels of cardiovascular drugs.
Specific drugs, such as Aspirin have been proven to help prevent men having heart attacks, but researchers say it appears not to be as effective for women.
Likewise, Digitalis is prescribed to patients with heart failure but is associated with a higher death rate in female patients than in male.