David J. Magid, M.D., M.P.H., of Kaiser Permanente, Denver, and colleagues examined the relationship between time of day and day of week and reperfusion treatment times for eligible ST-segment elevation myocardial infarction (STEMI) patients treated with fibrinolytic therapy or percutaneous coronary intervention (PCI).

The authors write that understanding the reasons for variation in reperfusion treatment times by patient arrival period, and whether such variation is common to all hospitals and to both fibrinolytic therapy and PCI, could inform the design and targeting of interventions to improve timely reperfusion.

The study included 68,439 patients with STEMI treated with fibrinolytic therapy and 33,647 treated with PCI from 1999 through 2002. The researchers classified patient hospital arrival period into regular hours (weekdays, 7 a.m.-5 p.m.) and off-hours (weekdays 5 p.m.-7 a.m. and weekends).

The researchers found that most fibrinolytic therapy (67.9 percent) and PCI patients (54.2 percent) were treated during off-hours. Door-to-drug times (the time from arriving at the hospital to receiving blood-clot dissolving medications) were slightly longer during off-hours (34 minutes) than regular hours (33 minutes). In contrast, door-to-balloon times (the time from arriving at the hospital to receiving PCI) were substantially longer during off-hours (116 minutes) than regular hours (94 minutes).

A lower percentage of patients met guideline recommended times for door-to-balloon during off-hours (26 percent) than regular hours (47 percent). Door-to-balloon times exceeding 120 minutes occurred much more commonly during off-hours (42 percent) than regular hours (28 percent). Longer off-hours door-to-balloon times were primarily due to a longer interval between obtaining the electrocardiogram and patient arrival at the catheterisation laboratory (off-hours 70 minutes vs. regular hours 49 minutes).

MEDICA.de; Source: American Medical Association (AMA)