Non-invasive mechanical ventilation for reperfusion myocardial injury prevention after endovascular surgeries in patients with ST-elevation myocardial infarction (STEMI)

Aim. To determine the need for pressure controlled non-invasive mechanical ventilation for reperfusion myocardial injury prevention in patients with ST-elevation myocardial infarction (STEMI). Methods. The study enrolled 61 patients admitted to the intensive care unit within 6 hours from the debut of chest pain, ST-segment elevation on electrocardiogram and oxygen saturation less than 90%. A percutaneous coronary intervention on an affected coronary artery was performed in all patients 30-90 minutes from admission. Non-invasive mechanical ventilation using the «MAQUET Servo-s» machine was started in patients of the first group (31 patients, mean age 66.3±10.7 years, males - 19, females - 12) with positive end expiratory pressure of 2-6 cm H2O, pressure support of 6-10 cm H2O, 40-60% O2 gas mix. Patients of the second group (comparison group, 30 patients, mean age 63.5±9.8 years, males - 16, females - 14) were offered a conventional treatment of ST-elevation myocardial infarction, including inhalations of humidified oxygen (6-8 liters per minute) using a nasal cannula. Results. Systolic, diastolic blood pressure and heart rate were 123.0±9.4 mm Hg, 81.2±11.3 mm Hg, 70.1±6.1 beats per minute in patients of the first group in 6 hours after admission. In patients of the comparison group the following parameters were measured as 157±12.4 mm Hg, 90.2±10.1 mm Hg, 92.6±10.2 beats per minute. The absolute risk increase of arrhythmias related to reperfusion myocardial injury was 17.8% (р <0.05) for the patients from the second group. Ejection fraction on a transthoracic echocardiogram (Teichholz method) was measured as 47.0±4.0 and 60.5±7.4% in patients from the first and the second groups respectively (р <0.05). Conclusion. Non-invasive mechanical ventilation decreases the risk for arrhythmias related to reperfusion myocardial injury, and increases the ejection fraction compared to conventional treatment and can be applied in patients with STEMI.