ECG changes during myocardial ischemia. Differences between men and women

Area of Science:

• Cardiology
• Medical Diagnostics
• Sex Differences in Health

Background:

• Women face higher short-term mortality from acute myocardial infarction (MI) compared to men.
• Existing disparities in risk factors and treatment access, including angiography and revascularization, contribute to this outcome.
• Electrocardiogram (ECG) findings are crucial for initiating acute MI therapies, highlighting the importance of understanding sex-based differences in ECG responses.

Purpose of the Study:

• To investigate whether differences in the magnitude of electrocardiographic changes during myocardial ischemia between men and women can explain reported sex biases in acute MI treatment.
• To determine if ST deviation patterns differ significantly between sexes during ischemic events.

Main Methods:

• Continuous vectorcardiography was used to monitor 178 patients (135 men, 43 women) with suspected MI for 24 hours.
• ECG changes were also assessed in 81 patients with stable angina undergoing elective angioplasty during the procedure.
• Summated ST deviation and maximum ST deviation during balloon inflation were quantified and compared between sexes.

Main Results:

• Patients suspected of MI showed significantly greater initial summated ST deviation in men (178 +/- 146 microV) compared to women (105 +/- 91 microV; P = .002).
• During angioplasty, men exhibited more pronounced maximum ST deviation (235 +/- 165 microV) than women (156 +/- 89 microV; P = .036).
• These findings indicate men have more pronounced ST changes during myocardial ischemia.

Conclusions:

• Men demonstrate more significant ST deviations during myocardial ischemia than women.
• Standardized ST deviation thresholds for initiating therapies like thrombolytics may inadvertently favor the treatment of men.
• A sex-adjusted threshold for administering thrombolytic drugs may be necessary to ensure equitable treatment for acute myocardial infarction.