Clinical Autonomic Research最新文献

{"title":"Attenuated cardiac autonomic function in patients with long-COVID with impaired orthostatic hemodynamics.","authors":"Rashmin Hira, Jacquie R Baker, Tanya Siddiqui, Aishani Patel, Felix Gabriel Ayala Valani, Matthew G Lloyd, John S Floras, Carlos A Morillo, Robert S Sheldon, Satish R Raj","doi":"10.1007/s10286-025-01107-x","DOIUrl":"10.1007/s10286-025-01107-x","url":null,"abstract":"<p><strong>Purpose: </strong>Long-coronavirus disease (long-COVID) is associated with initial orthostatic hypotension and postural orthostatic tachycardia syndrome. Whether altered autonomic tone underlies these abnormalities is unknown. We compared autonomic function between patients with long-COVID and healthy controls, and within patients with long-COVID with different orthostatic hemodynamic phenotypes.</p><p><strong>Methods: </strong>Patients with long-COVID (n = 94; F = 76; 42 years [36, 53 years] with initial orthostatic hypotension: n = 40; F = 32; 49 years [39, 57 years]; postural orthostatic tachycardia syndrome: n = 29; F = 26; 39 years [33, 47 years]; or no abnormalities: n = 25; F = 18; 42 years [35, 49 years]), and healthy controls (n = 33; F = 25; 49 years [30, 62 years]) completed a 10-min active stand with beat-to-beat hemodynamics. Heart rate variability, blood pressure variability, and baroreflex sensitivity were calculated as indirect measures of cardiovascular autonomic health. Continuous data (median [95% confidence interval]) were analyzed with Mann-Whitney U tests or Kruskal-Wallis tests with Dunn's corrections.</p><p><strong>Results: </strong>Patients with long-COVID had lower upright high frequency heart rate variability (p = 0.04) and low frequency blood pressure variability (p = 0.001) than controls. Patients with initial orthostatic hypotension had lower supine baroreflex sensitivity compared with patients without abnormalities (p = 0.01), and lower supine baroreflex sensitivity (p = 0.001) and high frequency heart rate variability (p = 0.03) than patients with postural orthostatic tachycardia syndrome. Patients with postural orthostatic tachycardia syndrome had lower upright high frequency heart rate variability (p < 0.001) and baroreflex sensitivity (p < 0.001) compared with patients without abnormalities and lower upright low frequency blood pressure variability (p = 0.04) compared with controls.</p><p><strong>Conclusions: </strong>Patients with long-COVID have attenuated cardiac autonomic function. Patients with initial orthostatic hypotension have lower supine baroreflex sensitivity. Patients with postural orthostatic tachycardia syndrome have lower upright vascular sympathetic and cardiac parasympathetic modulation. Long-COVID subgroups do not present with homogeneous pathophysiology, necessitating targeted treatment strategies.</p>","PeriodicalId":10168,"journal":{"name":"Clinical Autonomic Research","volume":" ","pages":"301-314"},"PeriodicalIF":3.9,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143000852","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Trends in syncope testing and admissions in the USA from 2006 through 2019.","authors":"Mohammed Ruzieh, Chen Bai, Stephen E Kimmel, Zachary D Goldberger, Osama Dasa, John W Petersen, Madeline Smoot, Emily S Edwards, Sujay R Kamisetty, Mamoun T Mardini","doi":"10.1007/s10286-024-01089-2","DOIUrl":"10.1007/s10286-024-01089-2","url":null,"abstract":"<p><strong>Introduction: </strong>Syncope is common, with bimodal distribution through life, peaking in adolescence and in the elderly, and overall increases in incidence with age among both men and women. In this context, syncope-related visits to emergency departments (ED), hospitalizations, and testing are a significant healthcare cost burden. Ultimately, understanding the volume of testing types and settings of syncope encounters may aid in more effective healthcare utilization and high value care for this patient population.</p><p><strong>Methods: </strong>Data for this study were collected from the Truven Health Analytics MarketScan Database from 2006 to 2019. This database contains both commercially insured patients and those with Medicare coverage. Patients with the diagnosis of syncope were identified using International Classification of Diseases (ICD)-9 and -10 codes. We assessed the incidence of various tests for syncope evaluation and ED disposition for the study period.</p><p><strong>Results: </strong>The incidence of syncope among the study cohort rose from nine per 1000 patients to 13 per 1000 patients during the study period. The incidence of testing for syncope among multiple domains (neurologic, cardiac, blood testing) decreased in some categories, but routine testing remained prevalent. Women had a significantly lower incidence of testing in most testing domains. Discharge rate from the ED for patients presenting with syncope remained stable during the study period. However, admission rate to the hospital for those aged > 65 years increased during the study time.</p><p><strong>Conclusion: </strong>Testing and admissions for syncope remain prevalent and are drivers of healthcare-associated costs. There is a clear need for further work in developing a focused approach in the evaluation of syncope patients in order to mitigate healthcare costs and improve outcomes.</p>","PeriodicalId":10168,"journal":{"name":"Clinical Autonomic Research","volume":" ","pages":"315-325"},"PeriodicalIF":3.9,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142667305","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Risk of bradycardia and asystole during microelectrode recordings from the human vagus nerve.","authors":"Mikaela Patros, David G S Farmer, Matteo M Ottaviani, Tye Dawood, Marko Kumric, Josko Bozic, Matt I Badour, Antony R Bain, Ivan Drvis, Otto F Barak, Zeljko Dujic, Vaughan G Macefield","doi":"10.1007/s10286-024-01101-9","DOIUrl":"10.1007/s10286-024-01101-9","url":null,"abstract":"","PeriodicalId":10168,"journal":{"name":"Clinical Autonomic Research","volume":" ","pages":"341-345"},"PeriodicalIF":3.9,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142824023","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Accuracy of chat-based artificial intelligence for patient education on orthostatic hypotension.","authors":"W P Cheshire, P Sandroni, K Shouman, J K Cutsforth-Gregory, E A Coon, E E Benarroch, W Singer, P A Low","doi":"10.1007/s10286-025-01125-9","DOIUrl":"https://doi.org/10.1007/s10286-025-01125-9","url":null,"abstract":"","PeriodicalId":10168,"journal":{"name":"Clinical Autonomic Research","volume":" ","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143751239","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mechanical circulatory support reduces renal sympathetic nerve activity in an ovine model of acute myocardial infarction.","authors":"Tania Warnakulasuriya, Bindu George, Nigel Lever, Rohit Ramchandra","doi":"10.1007/s10286-024-01086-5","DOIUrl":"10.1007/s10286-024-01086-5","url":null,"abstract":"<p><strong>Purpose: </strong>The use of circulatory assist devices has been shown to improve glomerular filtration rate and reduce the incidence of acute kidney injury in patients following acute cardiac pathology. However, the mechanisms of improvement in kidney function are not clear. We tested the hypothesis that mechanical circulatory support would result in a decrease in directly recorded renal sympathetic nerve activity (RSNA) and mediate the improvement in renal blood flow (RBF) in a setting of acute myocardial infarction (AMI)-induced left ventricular systolic dysfunction.</p><p><strong>Methods: </strong>An anaesthetized ovine model was used to induce AMI (n = 8) using injections of microspheres into the left coronary artery in one group. The second group did not undergo embolization (n = 6). The effects of mechanical circulatory support using the Impella CP on directly recorded renal sympathetic nerve activity were examined in these two groups of animals.</p><p><strong>Results: </strong>Injection of microspheres resulted in a drop in mean arterial pressure (MAP) of 21 ± 4 mmHg compared to baseline values (p < 0.05; n = 8). This was associated with a 67% increase in renal sympathetic nerve activity (RSNA; from 16 ± 5 to 21 ± 5 spikes/s; p < 0.05; n = 7). Impella CP support significantly increased MAP by 13 ± 1.5 mmHg at pump level 8 (p < 0.05) in the AMI group. Incremental pump support resulted in a significant decrease in RSNA (p < 0.05) in both groups. At pump level P8 in the AMI group, RSNA was decreased by 21 ± 5.5% compared to pump level P0 when the pump was not on.</p><p><strong>Conclusion: </strong>Our data indicate that the improvement in kidney function following mechanical circulatory support may be mediated in part by renal sympathoinhibition.</p>","PeriodicalId":10168,"journal":{"name":"Clinical Autonomic Research","volume":" ","pages":"193-203"},"PeriodicalIF":3.9,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12000230/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142726444","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sympathetic nerve activity and response to physiological stress in Takotsubo syndrome.","authors":"Christina Ekenbäck, Jonas Persson, Per Tornvall, Lena Forsberg, Jonas Spaak","doi":"10.1007/s10286-024-01082-9","DOIUrl":"10.1007/s10286-024-01082-9","url":null,"abstract":"<p><strong>Purpose: </strong>The prevailing hypothesis posits that Takotsubo syndrome (TTS) is caused by massive sympathetic activation, yet supporting evidence remains inconsistent. The objectives of the present study were to determine whether sympathetic activity and reactivity are enhanced in the recovery phase of TTS, and to evaluate the effect of selective β1-receptor blockade on sympathetic reactivity.</p><p><strong>Methods: </strong>We conducted a case-control study that included 18 female patients with TTS and 13 age- and sex-matched controls. Muscle sympathetic nerve activity was measured through microneurography of the peroneal nerve at rest and during the cold pressor test. In the TTS group, recordings were repeated after randomisation to intravenous metoprolol or placebo. In 10 TTS patients, cardiac sympathetic activity was assessed using iodine 123-metaiodobenzylguanidine scintigraphy. Blood samples were collected during hospitalisation.</p><p><strong>Results: </strong>Microneurography was performed a median of 27.5 days after patient admission. There were no significant differences in burst incidence, burst frequency, burst height or burst area between the TTS patients and the controls at rest, during stress or after administration of intravenous metoprolol. Iodine 123-metaiodobenzylguanidine scintigraphy was performed a median of 12.5 days after admission, revealing decreased early 1.54 ± 0.13 and late 1.40 ± 0.13 heart-to-mediastinum ratios, and an increased washout rate of 41.8 ± 12.1%. Catecholamine metabolites were comparable between the study groups.</p><p><strong>Conclusion: </strong>General sympathetic hyperactivity or hyperreactivity unlikely contributes to TTS, as catecholamine levels and muscle sympathetic nerve activity at rest and during stress were similar between the TTS patients and the controls. As scintigraphy showed increased cardiac sympathetic activity, a pathological cardiac adrenergic response and vulnerability to sympathetic activation may be crucial for the development of the syndrome.</p>","PeriodicalId":10168,"journal":{"name":"Clinical Autonomic Research","volume":" ","pages":"205-214"},"PeriodicalIF":3.9,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12000160/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142638526","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Can standing replace upright tilt table testing in the diagnosis of postural tachycardia syndrome (POTS) in the young?","authors":"Julian M Stewart, Marvin S Medow","doi":"10.1007/s10286-024-01080-x","DOIUrl":"10.1007/s10286-024-01080-x","url":null,"abstract":"<p><strong>Purpose: </strong>We compared standing and upright tilt in patients with postural tachycardia syndrome (POTS) and healthy volunteers to determine whether standing accurately tests for POTS in youngsters < 19 years. POTS in adolescents is defined by orthostatic intolerance plus sustained excessive upright tachycardia, without hypotension during upright tilt. We examined whether active standing is a valid classifier for POTS in adolescents compared to tilt.</p><p><strong>Methods: </strong>Patients with POTS (N = 36, 12.2-18.8 years) and healthy volunteers (N = 39, 13.1-18.9 years) performed stand for a minimum of 5-min and were tilted to 70° for 10 min. Receiver operating characteristics analyses (ROC) were performed at 5-min stand, and at 5  and 10 min tilt for optimal threshold for heart rate (HR) increase (ΔHR), and test sensitivity and specificity.</p><p><strong>Results: </strong>Most subjects were unable to stand for 10 min. ΔHRs at 5 min stand were higher in POTS (31 ± 3) compared with control (21 ± 2) and elevated at 5- or 10-min tilt in POTS (51 ± 3 and 51 ± 2) versus control (26 ± 2 and 25 ± 2) compared with standing. ΔHR in POTS and controls for 10 min were not different from 5 min. For 5 min stand ROC threshold was 26 beats per min (bpm), sensitivity of 70.6%, and specificity of 68.2% compared with 39 bpm, 88.2%, and 95.1% for 5 min tilt, and 40 bpm, 94.1%, and 95.1% for 10-min tilt. A precision-recall graph confirmed the superior discriminating ability of 5 min and 10 min tilt compared to 5 min stand.</p><p><strong>Conclusions: </strong>The stand test is relatively non-specific and imprecise compared to tilt and does not satisfactorily distinguish POTS from control in patients aged < 19 years old.</p>","PeriodicalId":10168,"journal":{"name":"Clinical Autonomic Research","volume":" ","pages":"257-266"},"PeriodicalIF":3.9,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142726210","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"iSTAND trial of IVIG in POTS: a step in the right direction, but more studies are needed.","authors":"Kamal R Chémali, Svetlana Blitshteyn, Jaime Abraham Perez, Jill Schofield","doi":"10.1007/s10286-024-01087-4","DOIUrl":"10.1007/s10286-024-01087-4","url":null,"abstract":"","PeriodicalId":10168,"journal":{"name":"Clinical Autonomic Research","volume":" ","pages":"335-337"},"PeriodicalIF":3.9,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142638524","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Serotonin does not seem to play a major role in eliciting vasovagal syncope.","authors":"Paolo Alboni","doi":"10.1007/s10286-024-01092-7","DOIUrl":"10.1007/s10286-024-01092-7","url":null,"abstract":"","PeriodicalId":10168,"journal":{"name":"Clinical Autonomic Research","volume":" ","pages":"329-331"},"PeriodicalIF":3.9,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142680990","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Resting beat-to-beat blood pressure variability in humans: role of alpha-1 adrenergic receptors.","authors":"Rosa V D Guerrero, Lauro C Vianna, Georgia C S Lehnen, Mauricio Daher, André L Teixeira, Igor A Fernandes","doi":"10.1007/s10286-024-01105-5","DOIUrl":"10.1007/s10286-024-01105-5","url":null,"abstract":"<p><strong>Purpose: </strong>Resting beat-to-beat blood pressure variability is a strong predictor of cardiovascular events and mortality. However, its underlying mechanisms remain incompletely understood. Given that the sympathetic nervous system plays a pivotal role in cardiovascular regulation, we hypothesized that alpha-1 adrenergic receptors (the main sympathetic receptor controlling peripheral vasoconstriction) may contribute to resting beat-to-beat blood pressure variability.</p><p><strong>Methods: </strong>Beat-to-beat heart rate (electrocardiography) and blood pressure (photoplethysmography) were continuously measured before and 2 h following, selective blockade of alpha-1 adrenergic receptors via oral administration of prazosin (1 mg/20 kg) in ten young healthy adults (two women). Cardiac output and total peripheral resistance were estimated using the ModelFlow method.</p><p><strong>Results: </strong>Selective blockade of alpha-1 adrenergic receptors was confirmed by the marked reduction in the pressor response to intravenous infusion of phenylephrine hydrochloride (-80 ± 15%, P = 0.001 versus pre-prazosin). The blockade significantly decreased the standard deviation of the systolic (pre-prazosin versus post-prazosin: 5.6 ± 1.4 versus 3.8 ± 0.7 mmHg, P = 0.002), diastolic (3.2 ± 1.2 versus 2.2 ± 0.5 mmHg, P = 0.022), and mean blood pressure (3.7 ± 1.2 versus 2.5 ± 0.5 mmHg, P = 0.009), as well as total peripheral resistance (0.8 ± 0.5 versus 0.5 ± 0.1 mmHg/L/min, P = 0.047), but not cardiac output (521 ± 188 versus 453 ± 160 mL/min, P = 0.321). Similar results were found using different indices of variability.</p><p><strong>Conclusion: </strong>These findings indicate that alpha-1 adrenergic receptors play a significant role in regulating resting beat-to-beat blood pressure variability in young, healthy adults.</p>","PeriodicalId":10168,"journal":{"name":"Clinical Autonomic Research","volume":" ","pages":"277-284"},"PeriodicalIF":3.9,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143000940","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}