Publications by authors named "M M Demidova"
Background: The T-peak-to-T-end ( T) interval has shown potential in predicting ventricular arrhythmic risk. It is an appealing index to be measured during ischemia since it is less influenced by ST-segment changes than the early part of the T wave. A time-warping-based index, derived from a spatially transformed PCA lead, [Formula: see text], quantifying changes in the T morphology, has previously demonstrated utility in tracking repolarization changes induced by a 5-minute ischemia model in humans.
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- The study examined the impact of early ventricular arrhythmias (VAs) on the prognosis of patients with ST-segment elevation myocardial infarction (STEMI), focusing on the type and timing of these arrhythmias.
- Nonmonomorphic VT or VF was rare, occurring in only 3.4% of patients, but early VAs were linked to significantly higher risks of both in-hospital and longer-term mortality.
- Results indicated that VAs occurring after primary percutaneous coronary intervention (PCI) showed greater mortality risk compared to those before PCI, while the type of VA (monomorphic vs. nonmonomorphic) did not significantly influence long-term outcomes.
Article Synopsis
- - The study investigates how early ischemic conditions affect action potential duration (APD) prolongation and its link to arrhythmias, specifically focusing on phase 1A ventricular fibrillation (VF) during coronary occlusion in pigs.
- - Results revealed that significant prolongation of the activation-repolarization interval (ARIc) occurred shortly after occlusion and was strongly correlated with the development of VF and changes in the QT interval on ECG.
- - Patch-clamp experiments showed that while some substances did not affect APD, the compound pinacidil induced both initial APD prolongation and eventual shortening, highlighting complex mechanisms at play during ischemia.
In myocardial ischemia, melatonin confers antiarrhythmic action, but its electrocardiographic expression is unclear. We aimed to evaluate the effects of melatonin treatment on electrocardiogram (ECG) parameters reflecting major arrhythmogenic factors and to test the association of these parameters with ventricular fibrillation (VF) incidence. Myocardial ischemia was induced by 40 min coronary artery occlusion in 25 anesthetized pigs.
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