|
|
 |
 |
|
|
| Stroke risk highest shortly after ACS |
|
04 February 2006
US investigators have reported an increased risk of a cerebrovascular event after an acute coronary syndrome (ACS), especially within the first 30 days. "Given the relatively low incidence of stroke after ACS, only a few studies have been sufficiently large enough to provide adequate power for multivariate analysis of risk factors," they say. The team therefore analysed stroke outcomes in the 10,288 patients with ACS who were recruited to the Orbofiban in Patients with Unstable Coronary Sydromes-Thrombolysis in Myocardial Infarction (OPUS-TIMI) trial.
During 10 months of follow-up, 150 cerebrovascular events were recorded, comprising 67 ischaemic strokes, 44 transient ischaemic attacks (TIA), 14 intracerebral haemorrhages (ICH), and 25 events of undetermined type. Within the first 30 days of enrolment, the cerebrovascular event rate was 0.5%, but thereafter declined to a constant rate of 0.07% per month. For the entire period of follow-up, the team found that ST-elevation myocardial infarction at enrolment, a pulse rate of 66 beats/min or over, diabetes, prior ischaemic stroke, and history of hypertension were significant risk factors for a cerebrovascular event.
The team suggest that increased heart rate could have been more common in patients with risk factors for cardioembolism such as cardiac arrhythmia, decreased ejection fraction, or hypotension with hypoperfusion. When outcome within the first 30 days after enrolment was evaluated, history of stroke or hypertension was no longer statistically significant predictors of a cerebrovascular event. They further hypothesise that ischaemic stroke or TIA risk during the initial period may be more influenced by ACS-induced changes in cardiac function rather than pre-existing chronic stroke risk factors. Patients who were over 70 years of age, and those with a history of hypertension, coronary artery disease, or previous TIA were at increased risk of suffering an ICH during follow-up.
"Given that stroke after ACS, although uncommon, is frequently disabling, we believe that it is an important target for prevention strategies," say Dr Eric Smith (Massachusetts General Hospital, Boston) and colleagues. "Because there are many shared risk factors for both ischaemic heart disease and cerebrovascular disease, close adherence to current guidelines for risk reduction after ACS may also affect cerebrovascular disease."
Reference:
Am Heart J 2006; 151 (2): 338-344.
 Back to selection |
|
 |
|
|
|
