Influence of sex on the timing of coronary angiography and the prescription of antiplatelet therapy in patients with nonST-segment elevation myocardial infarction

OBJECTIVES

To assess differences in the clinical management of nonST-segment elevation myocardial infarction (NSTEMI), including in-hospital events, according to biological sex.

MATERIAL AND METHODS

Prospective observational multicenter study of patients diagnosed with NSTEMI and atherosclerosis who underwent coronary angiography.

RESULTS

We enrolled 1020 patients in April and May 2022; 240 (23.5%) were women. Women were older than men on average (72.6 vs 66.5 years, P .001), and more women were frail (17.1% vs 5.6%, P .001). No difference was observed in pretreatment with any P2Y12 inhibitor (prescribed in 68.8% of women vs 70.2% of men, P = .67); however, more women than men were prescribed clopidogrel (56% vs 44%, P = .009). Women prescribed clopidogrel were more often under the age of 75 years and not frail. Coronary angiography was performed within 24 hours less corooften in women (29.8% vs 36.9%, P = .03) even when high risk was recognized. Frailty was independently associated with deferring coronary angiography in the adjusted analysis; biological sex by itself was not related. The frequency and type of revascularization were the same in both sexes, and there were no differences in in-hospital cardiovascular events.

CONCLUSION

Women were more often prescribed less potent antithrombotic therapy than men. Frailty, but not sex, correlated independently with deferral of coronary angiography. However, we detected no differences in the frequency of coronary revascularization or in-hospital events according to sex.

Time from electrocardiographic diagnosis of ST-elevation myocardial infarction to guidewire crossing in patients transferred to a hospital for primary angioplasty: factors associated with delay

OBJECTIVES

To identify predictors of primary angioplasty delay in patients with ST-elevation myocardial infarction (STEMI) transported from out-of-hospital sites or from hospitals without percutaneous coronary intervention (PCI) suites.

MATERIAL AND METHODS

Retrospective cohort study of cases between 2008 and 2018 in a university hospital receiving patients diagnosed with STEMI who required a PCI. We performed linear and multivariate regression analyses to identify factors that predicted delay in interpreting a diagnostic electrocardiogram (ECG) until the guidewire passed the lesion (diagnosis-guidewire-crossing time).

RESULTS

A total of 1039 cases were studied; 296 patients (28.4%) had delays of more than 120 minutes between STEMI diagnosis and guidewire crossing. Factors associated with PCI delay were advanced age (odds ratio [OR] = 1.02; 95% CI, 1.01-1.04]), severe heart failure on admission (OR = 2.28; 95% CI, 1.23-4.22), history of cardiac bypass surgery (OR = 10.01; 95% CI, 2.60-41.81), out-of-hospital cardiac arrest (OR = 4.34; 95% CI, 1.84-10.32), lateral ischemia (OR, 1.64; 95% CI, 1.06-2.51), first medical attention in a hospital without a PCI suite (OR = 1.52; 95% CI, 1.05-2.21), first medical attention outside regular working hours (OR = 1.46; 95% CI, 1.06-2.02), and distance in kilometers to a PCI suite (OR = 1.04; 95% CI, 1.03-1.05).

CONCLUSION

Patients with STEMI who required transport to a hospital with a PCI suite experienced primary angioplasty delays. Delays were related to logistical and clinical factors as well as to infarction characteristics.

Levocarnitine protects H9c2 rat cardiomyocytes from H2O2-induced mitochondrial dysfunction and apoptosis

BACKGROUND

Although the protective effects of levocarnitine in patients with ischemic heart disease are related to the attenuation of oxidative stress injury, the exact mechanisms involved have yet to be fully understood. Our aim was to investigate the potential protective effects of levocarnitine pretreatment against oxidative stress in rat H9c2 cardiomyocytes.

METHODS

Cardiomyocytes were exposed to H2O2 to create an oxidative stress model. The cells were pretreated with 50, 100, or 200 μM levocarnitine for 1 hour before H2O2 exposure.

RESULTS

H2O2 exposure led to significant activation of oxidative stress in the cells, characterized by reduced viability, increased intracellular reactive oxygen species, lipid peroxidation, and reduced intracellular antioxidant activity. Mitochondrial dysfunction was also observed following H2O2 exposure, reflected by the loss of mitochondrial transmembrane potential and intracellular adenosine triphosphate. These pathophysiological processes led to cardiomyocyte apoptosis through activation of the intrinsic apoptotic pathway. More importantly, the levocarnitine pretreatment attenuated the H2O2-induced oxidative injury significantly, preserved mitochondrial function, and partially prevented cardiomyocyte apoptosis during the oxidative stress reaction. Western blotting analyses suggested that levocarnitine pretreatment increased plasma protein levels of Bcl-2, reduced Bax, and attenuated cytochrome C leakage from the mitochondria in the cells.

CONCLUSION

Our in vitro study indicated that levocarnitine pretreatment may protect cardiomyocytes from oxidative stress-related damage.