Elevated plasma homocysteine level is associated with poor ST-segment resolution in patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention at high altitude

Abstract Background and purpose: Poor ST-segment resolution (STR) is strongly associated with poor prognosis in patients with ST segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PPCI). previous studies suggested higher HCY level in the people who live in high altitudes, so a retrospective analysis is conducted to examine the potential relationship between elevated serum HCY and poor STR after PPCI at high altitudes. Methods: This retrospective analysis included 308 high-altitude dwelling patients (1800-2200 meters elevation from the sea level) undergoing PPCI for STEMI during a period from September 2021 to March 2022. Clinical data were collected and statistically analyzed. Results: In comparison to the patients with normal plasma homocysteine (≤15 mmol/L; n = 155), patients with elevated homocysteine (>15 mmol/L) had higher percentage of men (92.81% vs. 80.00%; p = 0.001) and smoker (79.08% vs. 63.87%; p = 0.003), but no difference in other key baseline characteristics. The rate of complete ST-segment resolution after PPCI (≥ 70%) was 83.23% in the control group and 49.67% in the elevated HCY group (p ≤ 0.001). In multivariable regression analysis, poor ST-segment resolution (<70%) was independently associated with longer pain-to-balloon time (OR 0.832; 95%CI: 0.775–0.894), lower uric acid (OR 1.003; 95%CI: 1.000-1.005), and elevated HCY (OR 0.957 vs. normal HCY; 95%CI: 0.937–0.977). Conclusion: Elevated plasma HCY level was associated with poor ST segment resolution in patients undergoing PPCI STEMI at high altitude.