最近，美国明尼阿波利斯心脏研究所（Minneapolis Heart Institute）的学者对1000多例心肌梗死患者的发病时间与心肌坏死之程度进行了分析。结果提示，那些于凌晨1～5点间发病的患者往往病情较重，也即这一部分患者之心肌因缺血而损伤最严重。这一结果提示“心肌梗死患者之心肌坏死之程度确与发病时间有关”。事实上，类似的现旬已往在啮齿类动物之动物模型上早就得到了证实。

Heart Attack Severity May Depend on Time of Day

In study, early morning hours were the worst time

MONDAY, Nov. 28 (HealthDay News) -- The severity of a heart attack can be affected by the time of day it occurs, a new study suggests.

The analysis of data from more than 1,000 heart-attack patients revealed that the greatest amount of heart injury occurs when people have a heart attack between 1 a.m. and 5 a.m. The peak amount of damage that occurs during this time is 82 percent greater than during the time of day when injury is the lowest.

The findings could help lead to new ways to prevent heart attack, according to Minneapolis Heart Institute at Abbott Northwestern Hospital researchers.

The research builds on previous research done with rodents.

"We were trying to ascertain whether the time of day of when a heart attack occurs influences the amount of damage that the heart sustains, or was this just a phenomenon exhibited in rodents," said study senior author Dr. Jay Traverse, a cardiologist at the Minneapolis Heart Institute.

"It is important to understand that the heart's ability to protect itself against more severe damage varies over a 24-hour cycle. Identifying those protective changes may be particularly relevant for pharmaceutical manufacturers that are seeking to develop cardioprotective drugs," Traverse added in a Minneapolis Heart Institute Foundation news release.

The study was published online in the journal Circulation Research.