Electrocardiographic Scaling Reveals Differences in Electrocardiogram Interval Durations Between Marine and Terrestrial Mammals

Although the ability of marine mammals to lower heart rates for extended periods when diving is well documented, it is unclear whether marine mammals have electrophysiological adaptations that extend beyond overall bradycardia. We analyzed electrocardiographic data from 50 species of terrestrial mammals and 19 species of marine mammals to determine whether the electrical activity of the heart differs between these two groups of mammals. We also tested whether physiological state (i.e., anesthetized or conscious) affects electrocardiogram (ECG) parameters. Analyses of ECG waveform morphology (heart rate, P-wave duration, and PQ, PR, QRS, and QT intervals) revealed allometric relationships between body mass and all ECG intervals (as well as heart rate) for both groups of mammals and specific differences in ECG parameters between marine mammals and their terrestrial counterparts. Model outputs indicated that marine mammals had 19% longer P-waves, 24% longer QRS intervals, and 21% shorter QT intervals. In other words, marine mammals had slower atrial and ventricular depolarization, and faster ventricular repolarization than terrestrial mammals. Heart rates and PR intervals were not significantly different between marine and terrestrial mammals, and physiological state did not significantly affect any ECG parameter. On average, ECG interval durations of marine and terrestrial mammals scaled with body mass to the power of 0.21 (range: 0.19–0.23) rather than the expected 0.25&...
Source: Frontiers in Physiology - Category: Physiology Source Type: research

Related Links:

CONCLUSIONS: By using a specialized team and a standardized clinical care pathway, our institution was able to minimize adverse events caused by the anesthetic and surgical care of patients with EB. We recommend natural airway or nasal fiberoptic airway management, meticulous avoidance of shear stress on the skin, and a multidisciplinary approach to care. Supportive therapy such as perioperative blood transfusions and iron infusions are feasible for the treatment of chronic anemia in this population.PMID:34591805 | DOI:10.1213/ANE.0000000000005749
Source: Anesthesia and Analgesia - Category: Anesthesiology Authors: Source Type: research
Conclusion: Propofol induction results in significant immediate changes in ANS activity that include temporally relative elevation of cardiac sympathovagal balance and reduced sympathetic activity.Clinical Trial Registration: The study was approved by the Institutional Review Board of Taipei Veterans General Hospital (No. 2017-07-009CC) and is registered at ClinicalTrials.gov (https://clinicaltrials.gov/ct2/show/NCT03613961).
Source: Frontiers in Physiology - Category: Physiology Source Type: research
Conclusion: Administration of both 30 ng/kg/min and 90 ng/kg/min at 32°C had a positive inotropic effect and reduced afterload. We found no evidence of increased pro-arrhythmic activity after epinephrine infusion in hypothermic pigs. Our experiment therefore suggests that β₁-receptor stimulation with epinephrine could be a favorable strategy for providing cardiovascular support in hypothermic patients, at core temperatures>32°C.
Source: Frontiers in Physiology - Category: Physiology Source Type: research
Coronary artery spasm after coronary artery bypass graft (CABG) surgery is a rare and poorly understood event with high morbidity and mortality. When new regional wall motion abnormalities, electrocardiographic changes, or hemodynamic instability present after CABG surgery, after ruling out graft dysfunction, a high index of suspicion is needed for the prompt diagnosis and treatment of vasospasm, which requires coronary angiography.1 Although no consensus exists for its management, intracoronary and/or systemic vasodilators and hemodynamic support with an intra-aortic balloon pump (IABP) and extracorporeal membrane oxygena...
Source: Journal of Cardiothoracic and Vascular Anesthesia - Category: Anesthesiology Authors: Tags: Case Report Source Type: research
ConclusionsThis study for the first time identifies that the ECG response to DOX is modulated by anesthesia. Furthermore, this response demonstrated stark sex differences. These findings could have significant implications in clinical diagnosis of DOX cardiotoxicity.
Source: Physiological Reports - Category: Physiology Authors: Tags: ORIGINAL ARTICLE Source Type: research
CONCLUSIONS: The CCEeXAM is designed to assess a knowledge base that is shared with echocardiologists in addition to that which is unique to critical care. The National Board of Echocardiography certification establishes that the physician has achieved the ability to independently perform and interpret critical care echocardiography at a standard recognized by critical care professional societies encompassing a wide spectrum of backgrounds. The interest shown and the success achieved on the CCEeXAM by practitioners of critical care echocardiography support the standards set by the National Board of Echocardiography for...
Source: Critical Care Medicine - Category: Emergency Medicine Tags: Feature Articles Source Type: research
Cardiovasc Toxicol. 2021 Jul 24. doi: 10.1007/s12012-021-09675-w. Online ahead of print.ABSTRACTDrug-induced long QT syndrome (DI-LQTS) is fatal and known to have a higher incidence in women rather than in men. Multiple risk factors potentiate the incidence of DI-LQTS, but the actual contribution of obesity remains largely unexplored. Correspondingly, the present study is aimed to evaluate the susceptibility of DI-LQTS in WNIN/Ob rat in comparison with its lean counterpart using 3-lead electrocardiography. Four- and eight-month-old female WNIN/Ob and their lean controls were used for the experimentation. Non-invasive blood...
Source: Cardiovascular Toxicology - Category: Cardiology Authors: Source Type: research
Epilepsy Behav. 2021 Jul 5;122:108124. doi: 10.1016/j.yebeh.2021.108124. Online ahead of print.ABSTRACTSudden death in epilepsy or SUDEP is a fatal condition that accounts for more than 4000 deaths each year. Limited clinical and preclinical data on sudden death suggest critical contributions from autonomic, cardiac, and respiratory pathways. A potential mechanism for such sudden and severe cardiorespiratory dysregulation may be linked to acid reflux-induced laryngospasm. Here, we expand on our previous investigations and utilize a novel multimodal approach to provide visual evidence of acid reflux-initiated cardiorespirat...
Source: Epilepsy and Behaviour - Category: Neurology Authors: Source Type: research
CONCLUSIONS: Stellate ganglion neuronal populations exhibit cardiopulmonary integration and profound specificity toward the near-peak systolic phase of the cardiac cycle. This novel approach provides practically deployable tools to probe stellate ganglion function and its relationship to cardiopulmonary pathophysiology.PMID:34213390 | DOI:10.1152/ajpheart.00138.2021
Source: American Journal of Physiology. Heart and Circulatory Physiology - Category: Physiology Authors: Source Type: research
More News: Anesthesia | Anesthesiology | Cardiology | Electrocardiogram | Heart | Physiology