Objectives: The aim of this study was to assess whether transient episodes of symptomatic or silent myocardial ischemia after baroreceptor modulation of heart rate.
Background: Animal and human studies have shown that myocardial infarction is accompanied by an impairment of the baroreceptor influences on the sinus node. However, whether this also occurs during transient myocardial ischemia has never been documented.
Methods: In 12 patients undergoing coronary angiography, systolic blood pressure (intraarterial catheter) was reduced by an intravenous bolus of nitroglycerin during a spontaneous episode of transient chest pain and myocardial ischemia (ST segment depression on the electrocardiogram) and 30 min after recovery. The slope of the linear regression between the decrease in systolic blood pressure and the RR interval shortening was taken as the measure of baroreflex sensitivity.
Results: During ischemia, baroreflex sensitivity was 1.3 +/- 0.3 ms/mm Hg (mean +/- SEM), whereas after recovery it was markedly and significantly greater (2.6 +/- 0.5 ms/mm Hg, p < 0.01). Similar results were obtained in eight other patients who experienced a silent ischemic episode either spontaneously or during coronary angioplasty. The reduction in baroreflex sensitivity was similarly pronounced during inferior (10 patients) and anterior (10 patients) ischemia, and its magnitude showed little or no relation to the ischemia-dependent changes in blood pressure and heart rate.
Conclusions: Transient myocardial ischemia is associated with marked baroreflex impairment. The impairment occurs even during symptomless ischemic episodes and is therefore not related to pain or to other nonspecific influences on the baroreflex.
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http://dx.doi.org/10.1016/0735-1097(93)90771-r | DOI Listing |
Medicine (Baltimore)
November 2024
Department of Cardiology, Rabta Teaching Hospital, University of Medicine Tunis, Tunis, Tunisia.
Little is known about the effects of sodium-glucose co-transporter 2 inhibitors (SGLT2i) on atherosclerosis. We aimed to determine if a 90-day intake of Dapagliflozin could improve atherosclerosis biomarkers (namely endothelial function assessed by flow-mediated dilatation [FMD] and carotid intima-media thickness [CIMT]) in diabetic and non-diabetic acute coronary syndrome (ACS) patients when initiated in the early in-hospital phase. ATH-SGLT2i was a prospective, single-center, observational trial that included 113 SGLT2i naive patients who were admitted for ACS and who were prescribed Dapagliflozin at a fixed dose of 10 mg during their hospital stay for either type 2 diabetes or for heart failure.
View Article and Find Full Text PDFJAMA Cardiol
January 2025
Program of Medical and Population Genetics, Broad Institute of MIT (Massachusetts Institute of Technology) and Harvard, Cambridge, Massachusetts.
Importance: Treatment to lower high levels of low-density lipoprotein cholesterol (LDL-C) reduces incident coronary artery disease (CAD) risk but modestly increases the risk for incident type 2 diabetes (T2D). The extent to which genetic factors across the cholesterol spectrum are associated with incident T2D is not well understood.
Objective: To investigate the association of genetic predisposition to increased LDL-C levels with incident T2D risk.
Rheumatol Int
January 2025
Department of Rheumatology, Immunology and Internal Medicine, University Hospital in Kraków, Kraków, Poland.
Systemic lupus erythematosus (SLE) is a multisystem autoimmune rheumatic disease (ARD) that results from the dysregulation of multiple innate and adaptive immune pathways. Late-onset SLE (Lo-SLE) is the term used when the disease is first diagnosed after 50-65 years, though the standard age cut-off remains undefined. Defining "late-onset" as lupus with onset after 50 years is more biologically plausible as this roughly corresponds to the age of menopause.
View Article and Find Full Text PDFClin Res Cardiol
January 2025
Department of Cardiology, Medical School Theodor Fontane, University Hospital Ruppin-Brandenburg, Neuruppin, Germany.
Background: Heart failure (HF) is a heterogeneous clinical syndrome affecting a growing global population. Due to the high incidence of cardiovascular risk factors, a large proportion of the Western population is at risk for heart failure. Oxidative stress and inflammation play a crucial role in the pathophysiology of heart failure with preserved ejection fraction (HFpEF).
View Article and Find Full Text PDFCardiol Rev
January 2025
From the Department of Cardiology, Phelps Memorial Hospital/Northwell Health, Sleepy Hollow, NY.
The invention of the string galvanometer by Willem Einthoven in 1901 ushered in a new era of clinical investigation. Previous instruments were capable only of rudimentary measurements that were of limited utility. Advances in physiology and engineering allowed Einthoven to construct a device that was uniquely capable of recording the minute electrical currents of the heart.
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