ST elevation acute myocardial infarction (AMI) is routinely treated with either percutaneous coronary intervention (PCI) or thrombolysis. The time from symptom onset to treatment ("time-to-treatment") is traditionally considered important when predicting potential myocardial salvage in the clinic. Purpose: In the DANAMI-2 to: 1) assess the relation between time-to-treatment and myocardial salvage, 2) test an electrocardiographic (ECG) method for timing of the AMI. Methods: Patients were included if they had ECG evidence of ST elevation AMI, no prior AMI, and no ECG confounding factors. "Time-to-treatment" analysis was carried out in 346 pts receiving PCI and 429 pts receiving thrombolysis. Emergency department personnel recorded time-to-treatment from the pts. Myocardial salvage was calculated using the Aldrich/Clemmensen score for the initially predicted final infarct size and the Selvester QRS score for final infarct size. A subset of 175 pts with anterior AMI was used to test the ECG timing method (the Anderson-Wilkins acuteness score). Results: Mean salvage tended to depend on tertiles of time-to-treatment (mean salvage of 36% for "early" vs. 27% for "late," P = .06). This trend was most pronounced for pts receiving PCI compared to thrombolysis. The correlations between time-to-treatment and salvage were very low for both treatment strategies (r <.01). In contrast, there was a strong linear relationship between the ECG timing method and salvage, with almost no salvage with "late" ECG timing (P<.001) in the subgroup analysis. This association was present regardless of reperfusion strategy. Conclusion: Time-to-treatment had only minimal influence on myocardial salvage. This suggests that time-to-treatment should be considered with caution when predicting potential benefit of reperfusion therapy. This study further suggests that the ECG timing method might provide important independent information regarding the optimal therapy for pts with ST elevation AMI.
|Tidsskrift||Journal of Electrocardiology|
|Status||Udgivet - 1 okt. 2004|