Prognostic significance of QRS distortion and frontal QRS-T angle in patients with ST-elevation myocardial infarction

Significance of QRS scoring system in left ventricular function recovery after acute myocardial infarction

AIMS

The Selvester scoring system has been derived from ECG parameters for estimating infarct size. However, there is still a lack of evidence for Selvester score as an alternative to cardiac magnetic resonance (CMR) myocardial injury makers for risk stratification and prediction of left ventricular function (LVF) recovery among patients with ST-segment elevation myocardial infarction (STEMI).

METHODS AND RESULTS

This multicentre observational study enrolled 328 STEMI patients (88.4% men, 57.3 ± 10.6 years of age) undergoing CMR examination 1 week post-reperfusion therapy. Patients with baseline left ventricular ejection fraction (LVEF) < 50% underwent a follow-up CMR 6 months later, categorized into baseline normal LVF (ejection fraction [EF] ≥ 50% at baseline, n = 155); recovered LVF (EF < 50% at baseline and ≥50% after 6 months, n = 69); and reduced LVF (EF < 50% at baseline and after 6 months, n = 104). The median follow-up was 4 (3-4) years for all patients, with 61 patients experiencing major adverse cardiovascular event (MACEs). Patients with reduced LVF had a higher risk of MACEs than those with baseline normal LVF (P = 0.01), while the recovered LVF group had no significant difference (P > 0.05). A Selvester score >10 doubled the risk of MACEs in patients with systolic dysfunction (1.91 [1.02 to 3.58], P = 0.04). Additionally, Selvester score, baseline LVEF, transmural infarction, and peak CK-MB were independent predictors of recovered LVF, with Selvester score providing incremental predictive value to peak CK-MB in predicting recovered LVF (∆AUC = 0.07, P < 0.05).

CONCLUSIONS

The Selvester score improves risk stratification among STEMI patients beyond LVEF and provide independent and incremental information to clinical parameters in predicting recovered LVF.

An association between PM2.5 components and respiratory infectious diseases: A China's mainland-based study

The particulate matter with diameter of less than 2.5 µm (PM2.5) is an important risk factor for respiratory infectious diseases, such as scarlet fever, tuberculosis, and similar diseases. However, it is not clear which component of PM2.5 is more important for respiratory infectious diseases. Based on data from 31 provinces in mainland China obtained between 2013 and 2019, this study investigated the effects of different PM2.5 components, i.e., sulfate (SO42-), nitrate (NO3-), ammonium (NH4+), and organic matter (OM), and black carbon (BC), on respiratory infectious diseases incidence [pulmonary tuberculosis (PTB), scarlet fever (SF), influenza, hand, foot, and mouth disease (HFMD), and mumps]. Geographical probes and the Bayesian kernel machine regression (BKMR) model were used to investigate correlations, single-component effects, joint effects, and interactions between components, and subgroup analysis was used to assess regional and temporal heterogeneity. The results of geographical probes showed that the chemical components of PM2.5 were associated with the incidence of respiratory infectious diseases. BKMR results showed that the five components of PM2.5 were the main factors affecting the incidence of respiratory infectious diseases (PIP>0.5). The joint effect of influenza and mumps by co-exposure to the components showed a significant positive correlation, and the exposure-response curve for a single component was approximately linear. And single-component modelling revealed that OM and BC may be the most important factors influencing the incidence of respiratory infections. Moreover, respiratory infectious diseases in southern and southwestern China may be less affected by the PM2.5 component. This study is the first to explore the relationship between different components of PM2.5 and the incidence of five common respiratory infectious diseases in 31 provinces of mainland China, which provides a certain theoretical basis for future research.

Frontal QRS - T angle is associated with severity and prognosis of acute pulmonary embolism

INTRODUCTION

The pathological effects of acute pulmonary embolism (APE) on the right ventricle are one of the most important determinants of mortality in patients with APE. Frontal QRS-T angle (fQRSTa) predicts ventricular pathology and poor prognosis in many different cardiovascular diseases. In this study, we investigated whether there is a significant relationship between fQRSTa and APE severity.

MATERIAL AND METHODS

A total of 309 patients were included in this retrospective study. The severity of APE was classified as massive (high risk), submassive (intermediate risk), or nonmassive (low risk). fQRSTa calculated from standard ECGs.

RESULTS

fQRSTa was significantly higher in massive APE patients (p < 0.001). fQRSTa was also found to be significantly higher in the in-hospital mortality group (p < 0.001). fQRSTa was an independent risk factor for the development of massive APE (odds ratio:1.033; 95% CI: 1.012-1.052; p < 0.001).

CONCLUSION

Our study showed that increased fQRSTa predicts high-risk APE patients and mortality in APE patients.