Clinical Autonomic Research最新文献

{"title":"Stroke volume reduction impairs cerebrovascular regulation through ETCO₂ in postural orthostatic tachycardia syndrome.","authors":"Martin Miranda-Hurtado, Rashmin Hira, Kate M Bourne, Shaun Ranada, Jacquie R Baker, Robert S Sheldon, Satish R Raj","doi":"10.1007/s10286-025-01181-1","DOIUrl":"10.1007/s10286-025-01181-1","url":null,"abstract":"<p><strong>Background: </strong>Patients with postural orthostatic tachycardia syndrome (POTS) experience disabling symptoms such as brain fog related to reduced cerebral perfusion.</p><p><strong>Objective: </strong>The objective of this study is to determine the mediating role of carbon dioxide in the relationship between stroke volume and cerebral blood flow.</p><p><strong>Methods: </strong>A total of 15 female patients with POTS underwent head-up tilt testing under two conditions: with lower-body compression (higher stroke volume) and without (lower stroke volume). We analyzed cerebral blood flow velocity, respiratory, and cardiovascular responses using linear mixed-effects and mediation models to examine stroke volume-cerebral blood flow interactions. Granger causality and wavelet coherence assessed cerebral autoregulation.</p><p><strong>Results: </strong>Lower-body compression attenuated the reduction in stroke volume (-34 ml versus -23 ml; p < 0.01), end-tidal CO₂ (-6.4 mmHg versus -3.2 mmHg; p < 0.01), and mean middle cerebral artery blood flow velocity (-11.2 cm/s versus -4.2 cm/s; p < 0.01) during tilt. Mediation analysis revealed that carbon dioxide completely mediated the relationship between stroke volume and middle cerebral artery blood flow velocity, with a significant indirect effect (0.18 cm/s/ml, 95% confidence interval (CI) 0.058-0.33) and a nonsignificant direct effect (0.04 cm/s/ml, p = 0.5). Compression attenuated the association between stroke volume and carbon dioxide (-0.07 mmHg/ml; 95% CI -0.12 to -0.010; p = 0.02), as shown by the linear mixed-effect model, and reduced the directional influence of blood pressure on cerebral blood flow (ΔGranger causality: 0.12 (0.05-0.18) versus 0.05 (0.02-0.08); p < 0.01).</p><p><strong>Conclusions: </strong>Reduction in stroke volume leads to reduced cerebral perfusion in POTS, an effect likely mediated by decreased carbon dioxide.</p>","PeriodicalId":10168,"journal":{"name":"Clinical Autonomic Research","volume":" ","pages":"257-269"},"PeriodicalIF":4.6,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145762330","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":"Hemodynamic and cerebral oxygenation predictors of visual darkening in pediatric POTS: a cross-sectional study.","authors":"Soken Go, Akiko Kasuga, Kanako Hayashi, Misako Murakami, Saori Minami, Wakako Matsumoto, Ryo Takahashi, Yusuke Watanabe, Naoko Saito, Koko Ohno, Natsumi Morishita, Mika Takeshita, Shinichiro Morichi, Yu Ishida, Chiako Ishii, Naoko Kinjo, Yasuyo Kashiwagi, Gaku Yamanaka","doi":"10.1007/s10286-025-01169-x","DOIUrl":"10.1007/s10286-025-01169-x","url":null,"abstract":"<p><strong>Purpose: </strong>In pediatric postural tachycardia syndrome (POTS), presyncope is important yet undercharacterized. It undermines school participation and daily function, while objective bedside markers remain limited. We aimed to delineate clinically usable predictors by integrating cardiovascular responses and cerebral oxygenation during active standing. We operationalized presyncope as visual darkening and examined three physiological correlates: heart rate change (ΔHR), recovery time, and cerebral oxygenation (ΔOxyHb).</p><p><strong>Methods: </strong>We conducted a cross-sectional study of 49 pediatric patients with POTS (median age 14.2 years, 46.9% male). Continuous heart rate, blood pressure, and cerebral oxygenation were recorded during a 10-min active standing test; body mass index, inferior vena cava collapsibility index, and urinary sodium were also obtained. Robust regression identified independent predictors of visual darkening.</p><p><strong>Results: </strong>ΔHR emerged as the strongest predictor of visual darkening (coefficient 0.017, 95% CI 0.005-0.030, p = 0.004), followed by recovery time (coefficient 0.005, 95% CI 0.000-0.010, p = 0.055) and ΔOxyHb (coefficient 0.029, 95% CI  - 0.005 to 0.064, p = 0.098). The final model demonstrated strong discriminative ability (AUC 0.842). Patients reporting visual darkening exhibited significantly higher ΔHR (49 [42-59] vs. 41 [38-46] bpm, p = 0.009), longer recovery time (21 [19-28] vs. 19 [17-22] s, p = 0.041), and greater ΔOxyHb reduction (- 8.7 [ - 10.4 to - 2.4] vs. - 3.5 [- 7.0 to - 2.5] μmol/L, p = 0.039).</p><p><strong>Conclusions: </strong>Heart rate change upon standing is the most significant and clinically accessible predictor of visual darkening in pediatric POTS. The combined assessment of ΔHR, recovery time, and cerebral oxygenation offers a comprehensive evaluation of the risk of visual darkening, enabling personalized management strategies for pediatric patients.</p>","PeriodicalId":10168,"journal":{"name":"Clinical Autonomic Research","volume":" ","pages":"285-295"},"PeriodicalIF":4.6,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145667309","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":"Losartan treatment attenuates the cardiorenal alterations in a rat model of hemorrhagic insular stroke.","authors":"Liliane Ramos Dos Santos Machado, Itamar Couto Guedes Jesus, Marcos Eliezeck, Ana Caroline Ventris de Godoy, Matheus Henrique da Silva Cruz, Vanessa Pinho, Aline Silva de Miranda, Diogo Barros Peruchetti, Maria José Campagnole-Santos, Robson Augusto Souza Dos Santos, Silvia Guatimosim, Marco Antônio Peliky Fontes","doi":"10.1007/s10286-026-01188-2","DOIUrl":"10.1007/s10286-026-01188-2","url":null,"abstract":"","PeriodicalId":10168,"journal":{"name":"Clinical Autonomic Research","volume":" ","pages":"297-300"},"PeriodicalIF":4.6,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146212264","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":"Natriuretic peptide signaling as a therapeutic target in POTS: physiological opportunities and caveats.","authors":"Jens Jordan, Dominik Pesta, Cedric Moro","doi":"10.1007/s10286-026-01194-4","DOIUrl":"10.1007/s10286-026-01194-4","url":null,"abstract":"","PeriodicalId":10168,"journal":{"name":"Clinical Autonomic Research","volume":" ","pages":"311-313"},"PeriodicalIF":4.6,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13068727/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146212273","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":"Hyperadrenergic postural tachycardia syndrome associated with augmented neurovascular transduction.","authors":"Surat Kulapatana, Luis E Okamoto, Stefano Rigo, Vasile Urechie, Thomas W Cayton, Ruijing E Han, Giris Jacob, William D Dupont, Raffaello Furlan, Italo Biaggioni, André Diedrich","doi":"10.1007/s10286-025-01183-z","DOIUrl":"10.1007/s10286-025-01183-z","url":null,"abstract":"<p><strong>Purpose: </strong>Muscle sympathetic nerve activity (MSNA) is valuable for managing postural tachycardia syndrome (POTS), but microneurography is clinically impractical. We investigated whether the Valsalva phase 2 diastolic blood pressure rise (DBP_{VM2l_rise}) serves as a sympathetic marker and proposed enhanced neurovascular transduction as a pathophysiological mechanism in hyperadrenergic POTS.</p><p><strong>Methods: </strong>We included 21 POTS women and 22 healthy women to perform Valsalva and microneurography. MSNA spike rate was obtained using stationary wavelet transformation. The DBP_{VM2l_rise} cut point for hyperadrenergic POTS was optimized by the golden section search with its correlation to phase 2 MSNA spike rate as an objective function. We defined peripheral sympathetic neurovascular transduction (psNVT) as a ratio of DBP_{VM2l_rise} to early phase 2 MSNA increase. We compared Valsalva responses between the identified hyperadrenergic and non-hyperadrenergic POTS.</p><p><strong>Results: </strong>The DBP_{VM2l_rise} strongly correlated with the Valsalva phase 2 MSNA spike rate percentage change from baseline in healthy (r = 0.874, p < 0.001). The DBP_{VM2l_rise} cutoff criterion of 15 mmHg optimally separated POTS into 7 hyperadrenergic (≥ 15 mmHg, r = 0.902, p = 0.014) and 14 non-hyperadrenergic (< 15 mmHg, r = 0.629, p = 0.021). Although similar MSNA spike rate, the hyperadrenergic group had higher baseline systolic blood pressure (118 ± 10 vs 105 ± 12 mmHg, p = 0.026), shorter pressure recovery time (1.15 ± 0.75 vs 2.59 ± 1.17 s, p = 0.048), and higher psNVT (2.60 ± 1.02 vs 0.58 ± 0.46 mmHg/spike·s^-1, p < 0.001) than the non-hyperadrenergic POTS.</p><p><strong>Conclusion: </strong>DBP_{VM2l_rise} ≥ 15 mmHg could be a sympathetic clinical marker and could identify hyperadrenergic POTS, characterized by enhanced neurovascular transduction despite comparable MSNA levels. This novel pathophysiological insight underscores the importance of sympathetic markers in POTS clinical management.</p>","PeriodicalId":10168,"journal":{"name":"Clinical Autonomic Research","volume":" ","pages":"271-283"},"PeriodicalIF":4.6,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12931957/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145965163","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":"Acknowledgement to reviewers.","authors":"","doi":"10.1007/s10286-026-01195-3","DOIUrl":"https://doi.org/10.1007/s10286-026-01195-3","url":null,"abstract":"","PeriodicalId":10168,"journal":{"name":"Clinical Autonomic Research","volume":" ","pages":""},"PeriodicalIF":3.4,"publicationDate":"2026-02-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147269585","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":"Establishing minimally clinically important differences for the orthostatic hypotension questionnaire (OHQ).","authors":"Horacio Kaufmann, Jose-Alberto Palma, Ross Vickery, Lucy Norcliffe-Kaufmann, Beiyao Zheng, David Lewin, Tadhg Guerin","doi":"10.1007/s10286-025-01168-y","DOIUrl":"10.1007/s10286-025-01168-y","url":null,"abstract":"<p><strong>Purpose: </strong>Establish the minimally clinically important difference (MCID) for the Orthostatic Hypotension Questionnaire (OHQ).</p><p><strong>Background: </strong>Neurogenic orthostatic hypotension (nOH) causes disabling symptoms that impair daily function and quality of life. The OHQ is a validated patient-reported outcome with a symptom assessment (OHSA) and daily activity scale (OHDAS), widely used in clinical trials, despite the MCID being unestablished.</p><p><strong>Methods: </strong>We analyzed data from two phase 3, randomized placebo-controlled trials (SEQUOIA and REDWOOD), evaluating ampreloxetine for symptomatic nOH in patients with Parkinson disease, multiple system atrophy, and pure autonomic failure. Using anchor-based and distribution-based methods, we calculated the MCID for the total OHQ score, OHSA and OHDAS composite subscales, and for the single dizziness/lightheadedness question (OHSA1).</p><p><strong>Results: </strong>The analysis included 184 subjects from SEQUOIA and 128 from REDWOOD. The total OHQ MCID for improvement was a reduction of 0.9-1.2 points and for worsening was an increase of 0.7-1.1 points. The MCID for the OHSA composite ranged from a reduction of 0.9-1.3 points for improvement and an increase of 0.7-1.1 points for worsening. For the single-item OHSA1, the MCID was a reduction of 2.0-3.0 points for improvement and an increase of 1.0 point for worsening. Owing to poor correlation with the symptom-based anchors, a reliable MCID for the OHDAS component was not established.</p><p><strong>Conclusions: </strong>These MCID thresholds for the OHQ, OHSA and OHSA item 1 alone, enhance the interpretability of scores and support their use in evaluating clinical benefit.</p>","PeriodicalId":10168,"journal":{"name":"Clinical Autonomic Research","volume":" ","pages":"103-111"},"PeriodicalIF":4.6,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12982295/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145354106","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":"Clinical autonomic research: welcome to 2026.","authors":"Vaughan G Macefield, Horacio Kaufmann, Jens Jordan","doi":"10.1007/s10286-026-01196-2","DOIUrl":"10.1007/s10286-026-01196-2","url":null,"abstract":"","PeriodicalId":10168,"journal":{"name":"Clinical Autonomic Research","volume":" ","pages":"1-2"},"PeriodicalIF":3.4,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147302833","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":"Vestibulo-sympathetic interaction and otolith function in postural orthostatic tachycardia syndrome.","authors":"Tonghoon Woo, Yukang Kim, Jueun Kim, Jin-Woo Park, Sun-Uk Lee, Euyhyun Park, Gerard J Kim, Byung-Jo Kim, Ji-Soo Kim","doi":"10.1007/s10286-025-01163-3","DOIUrl":"10.1007/s10286-025-01163-3","url":null,"abstract":"<p><strong>Background and objective: </strong>The association between blood pressure variability (BPV) or heart rate variability (HRV) and the baroreflex is well established. However, the role of the vestibular-autonomic reflex in regulating BP and HR stability has primarily been explored only in experimental studies. We aimed to delineate the association of BPV and HRV with otolith function in postural orthostatic tachycardia syndrome (POTS).</p><p><strong>Methods: </strong>We retrospectively analyzed data from consecutive patients with POTS recruited between April 2021 and April 2025 at a tertiary referral-based hospital in South Korea. All patients underwent a head-up tilt table test using a Finometer^® device and cervical (cVEMP) and ocular vestibular evoked-myogenic potentials (oVEMP). The Finometer data were analyzed using a power spectral analysis. The Finometer, cVEMP, and oVEMP data were compared with those of 32 age- and sex-matched healthy participants.</p><p><strong>Results: </strong>A total of 47 patients with POTS (mean age <math><mo>±</mo></math> standard deviation [SD] = 33 <math><mo>±</mo></math> 10 years; 30 female patients) and 32 age- and sex-matched healthy participants were included for analysis. The n1-p1 amplitude of oVEMP was larger in patients with POTS than in healthy participants (p = 0.002). p13 latency was negatively correlated with the SD of heart rate in the supine position in patients with POTS (p = 0.001), a trend not observed in healthy participants. The n1-p1 amplitude (odds ratio [95% confidence interval] = 1.27 [1.08-1.49], p = 0.004) and root mean square of successive differences (RMSSD) during tilting (0.82 [0.72-0.93], p = 0.001) were associated with POTS after adjusting for other covariates.</p><p><strong>Conclusions: </strong>Otolithic function may play a role in accentuating BPV and HRV in POTS by contributing to enhanced sympathetic outflow.</p>","PeriodicalId":10168,"journal":{"name":"Clinical Autonomic Research","volume":" ","pages":"89-101"},"PeriodicalIF":4.6,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145225034","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":"Cerebral autoregulation in orthostatic hypotension and falls among older adults: a community-based exploratory study.","authors":"Nor Izzati Saedon, James Frith, Wan Azman Wan Ahmad, Maw Pin Tan","doi":"10.1007/s10286-025-01152-6","DOIUrl":"10.1007/s10286-025-01152-6","url":null,"abstract":"<p><strong>Background: </strong>Orthostatic hypotension (OH) is prevalent in older adults and is often associated with falls. However, the presence or absence of symptoms in OH may be mediated by cerebral autoregulation, which helps maintain cerebral perfusion during blood pressure fluctuations.</p><p><strong>Methods: </strong>We recruited 40 older adults (aged ≥ 55 years) from the Malaysian Elders Longitudinal Research (MELoR) cohort. Participants underwent cerebral blood flow velocity monitoring using transcranial Doppler ultrasonography and beat-to-beat blood pressure recording. Three protocols were used: active stand, mental arithmetic, and Valsalva manoeuvre. Participants were categorized, based on OH (≥ 30 mmHg systolic drop) and fall history, into four groups. Cerebrovascular resistance (CVR) was derived and analysed.</p><p><strong>Results: </strong>Participants with OH but no history of falls demonstrated preserved autoregulatory responses, as reflected by adaptive reductions in CVR. In contrast, fallers-regardless of OH status-had impaired CVR modulation. Significant group differences were found during the active stand test at 165 s and 180 s (p < 0.05).</p><p><strong>Conclusion: </strong>Preserved cerebral autoregulation may protect older adults with OH from symptomatic manifestations such as falls. Targeting cerebral autoregulation could offer novel approaches for preventing falls in this population.</p>","PeriodicalId":10168,"journal":{"name":"Clinical Autonomic Research","volume":" ","pages":"17-23"},"PeriodicalIF":4.6,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12982191/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145013978","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}