Discovery of plasma proteins associated with ventricular fibrillation during first ST-elevation myocardial infarction via proteomics

AIMS

The underlying biological mechanisms of ventricular fibrillation (VF) during acute myocardial infarction are largely unknown. To our knowledge, this is the first proteomic study for this trait, with the aim to identify and characterize proteins that are associated with VF during first ST-elevation myocardial infarction (STEMI).

METHODS AND RESULTS

We included 230 participants from a Danish ongoing case-control study on patients with first STEMI with VF (case, n = 110) and without VF (control, n = 120) before guided catheter insertion for primary percutaneous coronary intervention. The plasma proteome was investigated using mass spectrometry-based proteomics on plasma samples collected within 24 h of symptom onset, and one patient was excluded in quality control. In 229 STEMI patients {72% men, median age 62 years [interquartile range (IQR): 54-70]}, a median of 257 proteins (IQR: 244-281) were quantified per patient. A total of 26 proteins were associated with VF; these proteins were involved in several biological processes including blood coagulation, haemostasis, and immunity. After correcting for multiple testing, two up-regulated proteins remained significantly associated with VF, actin beta-like 2 [ACTBL2, fold change (FC) 2.25, P < 0.001, q = 0.023], and coagulation factor XIII-A (F13A1, FC 1.48, P < 0.001, q = 0.023). None of the proteins were correlated with anterior infarct location.

CONCLUSION

Ventricular fibrillation due to first STEMI was significantly associated with two up-regulated proteins (ACTBL2 and F13A1), suggesting that they may represent novel underlying molecular VF mechanisms. Further research is needed to determine whether these proteins are predictive biomarkers or acute phase response proteins to VF during acute ischaemia.

Increased Risk of Vertebral Fractures in Patients With Mild Autonomous Cortisol Secretion

CONTEXT

The risk of vertebral fractures (VFx) in patients with adrenal incidentalomas (AI) and mild autonomous cortisol secretion (MACS) is debated.

OBJECTIVE

To evaluate the VFx prevalence and incidence in patients with AI and MACS.

METHODS

This cross-sectional and longitudinal study using retrospective data from 4 Italian endocrinology units included 444 patients (cross-sectional arm) and 126 patients (longitudinal arm, 24.9 ± 5.3 months follow-up) to evaluate prevalent and incident VFx, respectively, in patients with MACS (MACS-yes) and without MACS (MACS-no). The main outcome measures were serum cortisol after a 1-mg dexamethasone test (F-1mgDST), bone mineral density (BMD) by dual-energy x-ray absorptiometry at spine (LS) and femur (FN), and VFx presence by x-ray.

RESULTS

Cross-sectional arm: 214 and 230 patients were MACS-yes and MACS-no, respectively, based on F-1mgDST >1.8 µg/dL (50 nmol/L). Patients with MACS had higher VFx prevalence (62.6%) than those without MACS (22.9%, P < .001); MACS was associated with prevalent VFx (odds ratio, 5.203; 95% CI, 3.361-8.055; P < .001; relative risk [RR] 2.07), regardless of age, body mass index, gender distribution, LS-BMD, and presence of type 2 diabetes mellitus (T2D). Longitudinal arm: 66 and 60 patients were MACS-no and MACS-yes, respectively. Patients without MACS showed higher number of incident VFx (36.4%) than patients without MACS (10.0%, P < .001); MACS was associated with the presence of an incident VFx (RR 4.561; 95% CI, 1.600-13.003; P = .005) regardless of age, LS-BMD, gender distribution, presence of prevalent VFx, and T2D. Results were confirmed in women and men when separately evaluated.

CONCLUSION

Women and men with AI and MACS are at higher risk of VFx.