Circadian Fluctuations in Efficacy of Streptokinase Thrombolysis
E. Goldhammer, L.Kharash, E.G. Abinader
Cardiology Dept., Bnei-Zion Medical Center and Technion Faculty of Medicine, Haifa
This study was designed to assess possible diurnal fluctuations in the efficacy of thrombolysis with streptokinase. 156 consecutive patients treated with streptokinase during the period 1.1.95-1.7.96 were studied retrospectively. Success or failure of thrombolysis was determined according to the accepted clinical and angiographic criteria starting at midnight, 12 times at 2-hour intervals, then 8 times at 3-hour intervals, and then 6 times at 4-hour intervals. A definite peak for successful thrombolysis was found in the late afternoon and early evening hours. Between 16:00-20:00 PM, in 30.23% successful thrombolysis were observed, compared to 6.98% between 20:00-24:00 PM (p<0.05) and in 10.53% between 00.00-04:00 AM (p<0.05).
Multiple regression analysis showed that the independent factor with the greatest impact on successful reperfusion was the actual time until thrombolysis (p=0.037); then came the interval from pain onset to streptokinase administration (p=0.020), while age and gender had much lesser impacts (p=0.328 and 0.215, respectively), and individual risk factors even less.
These findings may have several clinical implications: dose adjustment for the time of day may be required, with larger doses needed during morning hours, or preference for primary coronary angioplasty to avoid increase in bleeding complications due to higher doses of thrombolytic agents.