Signs of sympathetic activation are frequent during the early hours of anterior wall acute myocardial infarction, whereas parasympathetic reflexes predominate in inferior wall acute myocardial infarction. To assess the immediate autonomic responses to acute coronary occlusion, the high-frequency power and root-mean-square successive difference, frequency and time domain measures of heart rate (HR) variability were analyzed in 73 cases of significant (50 to 95%) coronary artery stenosis immediately before and during balloon occlusion (mean 99 seconds). The range of nonspecific changes was formed on the basis of a control group with no ischemia during dilatations of 16 totally occluded coronary arteries. Balloon occlusion of the left anterior descending artery (n = 35) caused an abnormal increase in the measures of HR variability as a sign of vagal activation in 8 patients (23%), and a significant decrease in HR variability in 4 (11%). Occlusion of the left circumflex artery (n = 19) caused an increase in HR variability in 5 patients (26%), and a decrease in 2 (11%). Right coronary artery occlusion (n = 19) caused an increase in HR variability in 5 patients (26%) and a decrease in 4 (21%). Thus, coronary occlusion causes immediate changes in HR variability in greater than one third of patients with coronary artery disease. The direction of these initial HR variability changes cannot be predicted by the site of coronary occlusion.
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http://dx.doi.org/10.1016/0002-9149(93)90857-9 | DOI Listing |
Entropy (Basel)
December 2024
Grupo de Sistema Cardiovascular, Instituto de Ingeniería Biomédica (IIBM), Facultad de Ingeniería, Universidad de Buenos Aires, Buenos Aires C1063, Argentina.
Myocardial ischaemia is a decompensation of the oxygen supply and demand ratio, often caused by coronary atherosclerosis. During the initial stage of ischaemia, the electrical activity of the heart is disrupted, increasing the risk of malignant arrhythmias. The aim of this study is to understand the differential behaviour of the ECG during occlusion of both the left anterior descending (LAD) and right anterior coronary artery (RCA), respectively, using spatio-temporal quantifiers from information theory.
View Article and Find Full Text PDFFront Cardiovasc Med
January 2025
Cardiology Department and Experimental Animal Center, Liaocheng People's Hospital of Shandong University and Liaocheng Hospital Affiliated to Shandong First Medical University, Liaocheng, Shandong, China.
Both de Winter syndrome and Wellens syndrome mainly indicate severe stenosis in the proximal segment of the anterior descending coronary artery. However, as research deepens, the accuracy and specificity of diagnosing proximal left anterior descending coronary artery (LAD) culprit lesions separately by de Winter syndrome or Wellens syndrome are challenged. The patient in this case developed both syndromes in a short period of time, and imaging showed significant stenosis of the proximal LAD, indicating a culprit lesion.
View Article and Find Full Text PDFEur Heart J Digit Health
January 2025
Lewisham and Greenwich NHS Trust, UK.
Retin Cases Brief Rep
January 2025
Department of Ophthalmology, American University of Beirut, Beirut, Lebanon.
Purpose: To report a successful case of vision restoration and macular reperfusion following branch retinal artery occlusion (BRAO) using pars plana vitrectomy with undermining the artery off the retinal bed.
Methods: This case report involves a 75-year-old patient who was diagnosed immediately with BRAO following cardiac catheterization procedure. An embolus at the superior retinal artery bifurcation was noted.
Microvasc Res
January 2025
Primary Health Care Center, Department of Health, Medicine and Caring Sciences, Faculty of Medicine and Health Sciences, Linköping University, Linköping, Sweden; Wallenberg Centre for Molecular Medicine, Linköping University, Linköping, Sweden. Electronic address:
Introduction: Little is known about the day-to-day variability of different skin microcirculation parameters, and how this variability is influenced by age and sex. The aim was to examine the day-to-day variability of microcirculatory parameters in relation to age and sex.
Methods: The cutaneous microcirculation was measured using a fiber optic probe integrating laser Doppler flowmetry (LDF) and diffuse reflectance spectroscopy (DRS) to measure oxygen saturation, red blood cell (RBC) tissue fraction, speed-resolved and conventional perfusion.
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