单选题：Questionsare based on the ．following passage．A recent study

Questionsare based on the ．following passage．
A recent study discovered that after surviving a heart attack, women have a slightly higher risk than men of dying in the next 30 days． The finding, researchers say, likely reflects the differences in the type of heart failure women experience, as well as the severity of the condition． (When the severity of the heart attack was taken into consideration, the mortality rates were more comparable between men and women)． The study examined medical records for more than 136,000 patients who had suffered from acute coronary syndromes (ACS急性冠状动脉综合症) ． They found that, in the month after first suffering ACS, the mortality rate among men was 5．3%, compared with 9．6% in women．
Under the umbrella term ACS there are multiple conditions--including heart attack caused by either completely or partially blocked blood supply, and what doctors refer to as "unstable angina (心绞痛) ," or when slowly decreasing blood and oxygen supply causes tightness in the chest, often a precursor (前兆) to the more severe types of heart attack． In this study, a heart attack caused by completely or nearly completely blocked blood supply was more likely to result in death after 30 days for women, compared with men． But for slightly less severe incidents, in which blood flow was partially or temporarily blocked, or in cases of unstable angina, women had lower mortality rates in the following 30 days than men did．
The differences, which incorporate both sex and type of ACS, suggest to researchers that physicians should take gender into consideration when assessing patients, and deciding on the best course of treatment or prevention． Women, who in the study tended to be older than men when they suffered heart attack, were also more likely to have concurrent complications (并发症) such as diabetes (糖尿病) or hypertension (高血压) ． And whereas men were more likely to have narrowed coronary arteries (冠状动脉）, which was less frequently the case among women． After a more severe incident, the fact that women had a greater risk for death suggested to doctors that it might be due to the subsequent reduction in blood flow． On the other hand, that they got along better than men after the less severe forms of ACS--partial blockage or unstable angina--was likely a result of the generally less severe blockages seen in women, as compared to men．
Heart disease is the leading cause of death among both men and women, and though, overall women's health outcomes continue to be slightly worse than men's, they are improving． And, researchers hope, with more studies illuminating the way in which heart disease uniquely impacts women and men, new gender- specific treatment methods may be the way of the future．

What does the study indicate about acute coronary syndromes (ACS) ? A．It can have different impact on women and men．
B．It can be regarded as the leading cause of death among these patients．
C．It can lead to more severe types of heart attack．
D．It can cause more deaths among men in the next 30 days．