Cor Vasa 2004, 45(4):157-166
Acute Q-wave myocardial infarction and non-Q-wave myocardial infarction in patients with ST-segment elevation
- 1 Ústav preventívnej a klinickej medicíny
- 2 Slovenská zdravotnícka univerzita, Bratislava, Slovenská republika
Aim of study:
The aim of the study was to compare, in patients with ST-segment elevation acute myocardial infarction (AMI), the demographic, medical history and clinical data of patients with acute Q-wave and non-Q-wave myocardial infarction (MI) and to examine the rationale for such classification.
Group of patients and method:
The project was carried out as a prospective multicenter study. Independent audit and data collection involved a total of 3,123 AMI patients in 66 centers from 16 September 1997 through 15 September 1998.
Results:
When comparing a subgroup of patients with acute Q-wave and non-Q-wave MI, the most striking differences (p £ 0.001) were seen in:
1. Diagnosis on admission. A diagnosis of AMI was established more often in patients with acute Q-wave MI. A diagnosis of suspected AMI, even recurrent AMI, was more frequent in patients with acute non-Q-wave MI.
2. More frequent treatment with acetylsalicylic acid in the history of patients with acute non-Q-wave MI.
3. A higher likelihood of successful thrombolytic therapy (TT) in patients with acute non-Q-wave MI.
4. Longer overall hospitalization time of patients with acute Q-wave MI, which, in fact, was only one day longer in patients with acute Q-wave MI compared with those with acute non-Q-wave MI. The most important end point, overall in-hospital mortality, was higher (p £ 0.05) in acute Q-wave MI patients (13.3%) compared with acute-non-Q-wave MI patients (10.3%). No significant differences were observed in the proportion of patients receiving TT and its initiation within versus after four hours.
Conclusion:
The appropriateness of classification of patients with ST-segment elevation into patients with acute Q-wave MI and those with non-Q-wave MI is only justified by the different in-hospital mortality. Acetylsalicylic acid administration prior to the development of an AMI significantly increases the proportion of acute non-Q-wave MI patients. The higher success rates of thrombolytic therapy in patients with acute non-Q-wave MI may reflect the fact that Q wave development was prevented in a proportion of patients with ST-segment elevation.
Keywords: Acute myocardial infarction; Electrocardiogram; Acute Q-wave infarction; Acute non-Q-wave infarction; Audit; Slovakia
Published: April 1, 2004 Show citation