OBJECTIVES: The present study investigated whether the onset of acute myocardial infarction and resistance to thrombolysis have similar circadian variations. BACKGROUND: Circadian variations of the onset of acute myocardial infarction and resistance to thrombolysis in the early morning have been reported. Some studies have also reported a secondary peak incidence in late evening; however, it is not known whether the resistance to thrombolysis has a similar circadian variation in these patients. METHODS: Six hundred eight Japanese patients with an acute myocardial infarction were the subjects of the study. Two hundred forty-four of the 608 patients were treated with thrombolysis within 12 h of the onset of symptoms. One hundred thirteen patients received urokinase, and 131 patients received tissue-type plasminogen activator (t-PA) over 60 min. Patency of the infarct-related artery, the primary end point of the study, was evaluated at 60 min after the initiation of thrombolytic therapy, and Thrombolysis in Myocardial Infarction (TIMI) grade 0, 1 or 2 was defined as resistant to thrombolysis. RESULTS: The onset of acute myocardial infarction and resistance to thrombolysis showed circadian variations with early morning and late evening peaks (p<0.001 and p<0.05, respectively). These circadian patterns showed similar distributions as evaluated with Spearman's method (r=0.70, p<0.05), although resistance to thrombolysis showed a phase difference of about 2 h earlier than the infarction incidence. The circadian variation of the resistance to thrombolysis was independent of the types of thrombolytic agents (urokinase or t-PA). CONCLUSIONS: These findings suggest that adjustment of treatment based on the time of the onset of symptoms may be warranted for the patients with acute myocardial infarction.
OBJECTIVES: The present study investigated whether the onset of acute myocardial infarction and resistance to thrombolysis have similar circadian variations. BACKGROUND: Circadian variations of the onset of acute myocardial infarction and resistance to thrombolysis in the early morning have been reported. Some studies have also reported a secondary peak incidence in late evening; however, it is not known whether the resistance to thrombolysis has a similar circadian variation in these patients. METHODS: Six hundred eight Japanese patients with an acute myocardial infarction were the subjects of the study. Two hundred forty-four of the 608 patients were treated with thrombolysis within 12 h of the onset of symptoms. One hundred thirteen patients received urokinase, and 131 patients received tissue-type plasminogen activator (t-PA) over 60 min. Patency of the infarct-related artery, the primary end point of the study, was evaluated at 60 min after the initiation of thrombolytic therapy, and Thrombolysis in Myocardial Infarction (TIMI) grade 0, 1 or 2 was defined as resistant to thrombolysis. RESULTS: The onset of acute myocardial infarction and resistance to thrombolysis showed circadian variations with early morning and late evening peaks (p<0.001 and p<0.05, respectively). These circadian patterns showed similar distributions as evaluated with Spearman's method (r=0.70, p<0.05), although resistance to thrombolysis showed a phase difference of about 2 h earlier than the infarction incidence. The circadian variation of the resistance to thrombolysis was independent of the types of thrombolytic agents (urokinase or t-PA). CONCLUSIONS: These findings suggest that adjustment of treatment based on the time of the onset of symptoms may be warranted for the patients with acute myocardial infarction.
Authors: Ann Coumbe; Ranjit John; Michael Kuskowski; Mehmet Agirbasli; Edward O McFalls; Selcuk Adabag Journal: BMC Cardiovasc Disord Date: 2011-10-20 Impact factor: 2.298
Authors: Ruchira Glaser; Srihari S Naidu; Faith Selzer; Alice K Jacobs; Warren K Laskey; Vankeepuram S Srinivas; James N Slater; Robert L Wilensky Journal: JACC Cardiovasc Interv Date: 2008-12 Impact factor: 11.195