Study on the relationship between long-term mortality and mean platelet volume at the first test in patients with ST-segment elevation myocardial infarction

ObjectiveTo investigate the relationship between long-term mortality and mean platelet volume(MPV) at the first test in patients with ST-segment elevation myocardial infarction(STEMI).

MethodsA total of 193 STEMI patients were followed up until October 8, 2019 after STEMI.According to the results of following up, the patients were divided into the survival group and death group.The blood routine indexes between the two groups were compared.The relationship between the blood routine indexes and long-term prognosis of STEMI was analyzed using multiple linear regression analysis, the cut-off value of MPV to long-term mortality of STEMI was analyzed using ROC analysis, the survival analysis was conducted by Kaplan-Meier curve, and the Log-Rank test was used.

ResultsThe results of blood routine indicators analysis showed that the levels of neutrophils, eosinophils, basophils and MPV in survival group were significantly lower than those in death group(P < 0.05 to P < 0.01).The cut-off value of MPV predicting long-term death in STEMI patients was 13.14 fL, the AUC was 0.741, the 95%CI was 0.658-0.824, the sensitivity was 78.94%(30/38), the specificity was 83.33%(105/126), the accuracy was 82.32% (135/164), the positive predictive value was 58.82% (30/51), and the negative predictive value was 92.92%(105/113).The results of ROC analysis showed that 8 patients died in the low-level MPV group(113 cases, MPV < 13.14 fL), and 30 patients died in the high level MPV group(51 cases, MPV ≥ 13.14 fL).The results of Kaplan-Meier analysis showed that the median survival time in low-level MPV group was 33 months(95%CI: 31.09-34.26), which was higher than that in high-level MPV group25 months, (95%CI: 22.13-27.29) (P < 0.01).The incidence rates of cerebrovascular events in low-level MPV group(24.78%) was lower than that in high-level MPV group(76.47%)(P < 0.01).Among 193 STEMI patients, 98 patients (50.78%) with different degrees of myocardial ischemia reperfusion injury were identified, and the level of MPV in patients with myocardial ischemia reperfusion injury was higher than that in patients without myocardial ischemia reperfusion injury(P < 0.01).

ConclusionsThe level of MPV in STEMI patients is significantly higher than that in healthy people at the first test, and the MPV can be used as an indicator for the long-term prognosis of STEMI patients.When the MPV is more than or equal to 13.14 fL, the risk of long-term death in patients with STEMI significantly increases, and the risk of myocardial ischemia reperfusion increases with the increasing of MPV level.