[Risk factors in postoperative myocardial infarction]

Area of Science:

• Cardiology
• Cardiovascular Surgery
• Critical Care Medicine

Background:

• Major surgery poses a risk for patients with a history of myocardial infarction (MI).
• Understanding the specific risk factors for perioperative MI in this high-risk group is crucial.

Purpose of the Study:

• To identify pathogenetic factors contributing to myocardial infarction in patients with previous infarcts undergoing major surgery.
• To analyze data from patients with prior MI before, during, and after surgical procedures.

Main Methods:

• Retrospective analysis of 335 operations in 214 patients with a history of myocardial infarction.
• Evaluation of patient data including arterial hypertension, arteriosclerosis, and other vascular diseases.
• Monitoring of intraoperative systolic blood pressure and postoperative red blood cell counts.
• Assessment of plasma catecholamine levels during the early postoperative period.

Main Results:

• Twenty-five instances of myocardial infarction occurred in the study cohort.
• High-risk patients exhibited arterial hypertension (≥160/95 mmHg) and advanced arteriosclerosis affecting multiple vascular beds.
• Myocardial necrosis was associated with intraoperative hypotension (systolic blood pressure ≤70 mmHg) or early postoperative anemia.
• The highest risk of infarction coincided with the early postoperative stress period, characterized by elevated catecholamines and increased myocardial oxygen demand.

Conclusions:

• Patients with prior myocardial infarction are at substantial risk for perioperative cardiac events during major surgery.
• Arterial hypertension, advanced arteriosclerosis, intraoperative hypotension, and postoperative anemia are significant contributors to perioperative MI.
• Postoperative stress and increased myocardial oxygen demand represent a critical period for infarction development.