Find research datasets worth reusing

Data set from the article Bari V, Vaini E, Pistuddi V, Fantinato A, Cairo B, De Maria B, Dalla Vecchia LA, Ranucci M, Porta A. Comparison of Causal and Non-causal Strategies for the Assessment of Baroreflex Sensitivity in Predicting Acute Kidney Dysfunction After Coronary Artery Bypass Grafting. Front Physiol. 2019 Oct 18;10:1319. doi: 10.3389/fphys.2019.01319. PMID: 31681021; PMCID: PMC6813722.

Data set from the article Bari V, Vaini E, Pistuddi V, Fantinato A, Cairo B, De Maria B, Dalla Vecchia LA, Ranucci M, Porta A. Comparison of Causal and Non-causal Strategies for the Assessment of Baroreflex Sensitivity in Predicting Acute Kidney Dysfunction After Coronary Artery Bypass Grafting. Front Physiol. 2019 Oct 18;10:1319. doi: 10.3389/fphys.2019.01319. PMID: 31681021; PMCID: PMC6813722. This is the abstract: Coronary artery bypass graft (CABG) surgery may lead to postoperative complications such as the acute kidney dysfunction (AKD), identified as any post-intervention increase of serum creatinine level. Cardiovascular control reflexes like the baroreflex can play a role in the AKD development. The aim of this study is to test whether baroreflex sensitivity (BRS) estimates derived from non-causal and causal approaches applied to spontaneous systolic arterial pressure (SAP) and heart period (HP) fluctuations can help in identifying subjects at risk of developing AKD after CABG and which BRS estimates provide the best performance. Electrocardiogram and invasive arterial pressure were acquired from 129 subjects (67 ± 10 years, 112 males) before (PRE) and after (POST) general anesthesia induction with propofol and remifentanil. Subjects were divided into AKDs (n = 29) or no AKDs (noAKDs, n = 100) according to the AKD development after CABG. The non-causal approach assesses the transfer function from the HP-SAP cross-spectrum in the low frequency (LF, 0.04-0.15 Hz) band. BRS was estimated according to three strategies: (i) sampling of the transfer function gain at the maximum of the HP-SAP squared coherence in the LF band; (ii) averaging of the transfer function gain in the LF band; (iii) sampling of the transfer function gain at the weighted central frequency of the spectral components of the SAP series dropping in the LF band. The causal approach separated the two arms of cardiovascular control (i.e., from SAP to HP and vice versa) and accounted for the confounding influences of respiration via system identification and modeling techniques. The causal approach provided a direct estimate of the gain from SAP to HP by observing the HP response to a simulated SAP rise from the identified model structure. Results show that BRS was significantly lower in AKDs than noAKDs during POST regardless of the strategy adopted for its computation. Moreover, all the BRS estimates during POST remained associated with AKD even after correction for demographic and clinical factors. Non-causal and causal BRS estimates exhibited similar performances. Baroreflex impairment is associated with post-CABG AKD and both non-causal and causal methods can be exploited to improve risk stratification of AKD after CABG.

Data set from Brunetta E, Shiffer D, Mandelli P, Achenza S, Folci M, Zumbo A, Minonzio M, Cairo B, Jacob G, Boccassini L, Puttini PS, Porta A, Furlan R. Autonomic Abnormalities in Patients With Primary Sjogren's Syndrome - Preliminary Results. Front Physiol. 2019 Aug 27;10:1104. doi: 10.3389/fphys.2019.01104. PMID: 31551801; PMCID: PMC6736624.

Data set from Brunetta E, Shiffer D, Mandelli P, Achenza S, Folci M, Zumbo A, Minonzio M, Cairo B, Jacob G, Boccassini L, Puttini PS, Porta A, Furlan R. Autonomic Abnormalities in Patients With Primary Sjogren's Syndrome - Preliminary Results. Front Physiol. 2019 Aug 27;10:1104. doi: 10.3389/fphys.2019.01104. PMID: 31551801; PMCID: PMC6736624.   This is the abstract: Primary Sjögren's syndrome (pSS) is an autoimmune disease affecting exocrine glands and extra-glandular organs. There are conflicting reports on the presence of autonomic dysfunction in pSS and no data are available on the functional status of sympathetic outflow to the vessels and baroreceptor [baroreflex sensitivity (BRS)] control mechanisms. We investigated the cardiac (cBRS) and sympathetic (sBRS) baroreceptor modulation in both time and frequency domains and the cardiovascular autonomic profile in pSS patients compared to healthy controls. Autonomic symptoms were quantified by the Composite Autonomic Symptom Scale (COMPASS31) three-item questionnaire. The EULAR Sjogren's syndrome patient reported index (ESSPRI) questionnaire evaluated the magnitude of pSS clinical symptoms, i.e., fatigue, pain, and sicca symptoms. Electrocardiogram, beat-by-beat arterial pressure (AP) and respiratory activity were continuously recorded in 17 pSS patients and 16 healthy controls, while supine and during 75° head-up tilt. In seven patients and seven controls, muscle sympathetic nerve activity (MSNA) was measured. Spectrum analysis of RR variability provided markers of cardiac vagal modulation (HFRR nu) and sympatho-vagal balance [low frequency (LF)/high frequency (HF)]. The power of LF (0.1 Hz) oscillations of systolic arterial pressure (SAP) variability (LFSAP) evaluated the vasomotor response to sympathetic stimulation. Compared to controls, pSS patients scored higher in total COMPASS31 (p < 0.0001) and all ESSPRI subdomains (fatigue, p = 0.005; pain, p = 0.0057; dryness, p < 0.0001). Abnormal scialometry (<1.5 ml/15 min) and Schirmer tests (<5 mm/5 min) were found in pSS patients and salivary flow rate was negatively associated with ESSPRI dryness (p = 0.0014). While supine, pSS patients had lower SEQcBRS index of cardiac baroreceptor sensitivity, higher HFRRnu (p = 0.021), lower LF/HF (p = 0.007), and greater MSNA (p = 0.038) than controls. No differences were observed in LFSAP between groups. During orthostatic challenge, although LFSAP increased similarly in both groups, MSNA was greater in pSS patients (p = 0.003). At rest pSS patients showed lower cBR control and greater parasympathetic modulation. Furthermore, greater sympathetic nerve activity was observed in pSS patients while supine and in response to gravitational challenge. We hypothesized that such enhanced sympathetic vasoconstrictor activity might reflect an attempt to maintain blood pressure in a setting of likely reduced vascular responsiveness.

Data set from Barbic F, Heusser K, Minonzio M, Shiffer D, Cairo B, Tank J, Jordan J, Diedrich A, Gauger P, Zamuner RA, Porta A, Furlan R. Effects of Prolonged Head-Down Bed Rest on Cardiac and Vascular Baroreceptor Modulation and Orthostatic Tolerance in Healthy Individuals. Front Physiol. 2019 Aug 23;10:1061. doi: 10.3389/fphys.2019.01061. PMID: 31507438; PMCID: PMC6716544.

Data set from Barbic F, Heusser K, Minonzio M, Shiffer D, Cairo B, Tank J, Jordan J, Diedrich A, Gauger P, Zamuner RA, Porta A, Furlan R. Effects of Prolonged Head-Down Bed Rest on Cardiac and Vascular Baroreceptor Modulation and Orthostatic Tolerance in Healthy Individuals. Front Physiol. 2019 Aug 23;10:1061. doi: 10.3389/fphys.2019.01061. PMID: 31507438; PMCID: PMC6716544.   This is the abstract: Orthostatic intolerance commonly occurs after prolonged bed rest, thus increasing the risk of syncope and falls. Baroreflex-mediated adjustments of heart rate and sympathetic vasomotor activity (muscle sympathetic nerve activity - MSNA) are crucial for orthostatic tolerance. We hypothesized that prolonged bed rest deconditioning alters overall baroreceptor functioning, thereby reducing orthostatic tolerance in healthy volunteers. As part of the European Space Agency Medium-term Bed Rest protocol, 10 volunteers were studied before and after 21 days of -6° head down bed rest (HDBR). In both conditions, subjects underwent ECG, beat-by-beat blood pressure, respiratory activity, and MSNA recordings while supine (REST) and during a 15-min 80° head-up tilt (TILT) followed by a 3-min -10 mmHg stepwise increase of lower body negative pressure to pre-syncope. Cardiac baroreflex sensitivity (cBRS) was obtained in the time (sequence method) and frequency domain (spectrum and cross-spectrum analyses of RR interval and systolic arterial pressure - SAP, variability). Baroreceptor modulation of sympathetic discharge activity to the vessels (sBRS) was estimated by the slope of the regression line between the percentage of MSNA burst occurrence and diastolic arterial pressure. Orthostatic tolerance significantly decreased after HDBR (12 ± 0.6 min) compared to before (21 ± 0.6 min). While supine, heart rate, SAP, and cBRS were unchanged before and after HDBR, sBRS gain was slightly depressed after than before HDBR (sBRS: -6.0 ± 1.1 versus -2.9 ± 1.5 burst% × mmHg-1, respectively). During TILT, HR was higher after than before HDBR (116 ± 4 b/min versus 100 ± 4 b/min, respectively), SAP was unmodified in both conditions, and cBRS indexes were lower after HDBR (α index: 3.4 ± 0.7 ms/mmHg; BRSSEQ 4.0 ± 1.0) than before (α index: 6.4 ± 1.0 ms/mmHg; BRSSEQ 6.8 ± 1.2). sBRS gain was significantly more depressed after HDBR than before (sBRS: -2.3 ± 0.7 versus -4.4 ± 0.4 burst% × mmHg-1, respectively). Our findings suggest that baroreflex-mediated adjustments in heart rate and MSNA are impaired after prolonged bed rest. The mechanism likely contributes to the decrease in orthostatic tolerance.

Data set from Martins de Abreu R, Porta A, Rehder-Santos P, Cairo B, Donisete da Silva C, De Favari Signini É, Sakaguchi CA, Catai AM. Effects of inspiratory muscle-training intensity on cardiovascular control in amateur cyclists. Am J Physiol Regul Integr Comp Physiol. 2019 Dec 1;317(6):R891-R902. doi: 10.1152/ajpregu.00167.2019. Epub 2019 Oct 9. PMID: 31596110.

Data set from Martins de Abreu R, Porta A, Rehder-Santos P, Cairo B, Donisete da Silva C, De Favari Signini É, Sakaguchi CA, Catai AM. Effects of inspiratory muscle-training intensity on cardiovascular control in amateur cyclists. Am J Physiol Regul Integr Comp Physiol. 2019 Dec 1;317(6):R891-R902. doi: 10.1152/ajpregu.00167.2019. Epub 2019 Oct 9. PMID: 31596110. This is the abstract: Chronic effects of inspiratory muscle training (IMT) on autonomic function and baroreflex regulation are poorly studied. This study aims at evaluating chronic effects of different IMT intensities on cardiovascular control in amateur cyclists. A longitudinal, randomized, controlled blind study was performed on 30 recreational male cyclists undergoing IMT for 11 wk. Participants were randomly allocated into sham-trained group (SHAM, n = 9), trained group at 60% of the maximal inspiratory pressure (MIP60, n = 10), and trained group at critical inspiratory pressure (CIP, n = 11). Electrocardiogram, finger arterial pressure, and respiratory movements were recorded before (PRE) and after (POST) training at rest in supine position (REST) and during active standing (STAND). From the beat-to-beat series of heart period (HP) and systolic arterial pressure (SAP), we computed time domain markers, frequency domain indexes in the low frequency (0.04-0.15 Hz) and high frequency (HF, 0.15-0.4 Hz) bands, an entropy-based complexity index (CI), and baroreflex markers estimated from spontaneous HP-SAP sequences. Compared with SHAM, the positive effect of MIP60 over the HP series led to the HF power increase during REST (PRE: 521.2 ± 447.5 ms2; POST: 1,161 ± 878.9 ms2) and the CI rise during STAND (PRE: 0.82 ± 0.18; POST: 0.97 ± 0.13). Conversely, the negative effect of CIP took the form of the decreased HP mean during STAND (PRE: 791 ± 71 ms; POST: 737 ± 95 ms). No effect of IMT was visible over SAP and baroreflex markers. These findings suggest that moderate-intensity IMT might be beneficial when the goal is to limit cardiac sympathetic hyperactivity at REST and/or in response to STAND.

Data set from De Maria B, Bari V, Cairo B, Vaini E, Esler M, Lambert E, Baumert M, Cerutti S, Dalla Vecchia L, Porta A. Characterization of the Asymmetry of the Cardiac and Sympathetic Arms of the Baroreflex From Spontaneous Variability During Incremental Head-Up Tilt. Front Physiol. 2019 Apr 2;10:342. doi: 10.3389/fphys.2019.00342. PMID: 31001137; PMCID: PMC6454064.

Data set from De Maria B, Bari V, Cairo B, Vaini E, Esler M, Lambert E, Baumert M, Cerutti S, Dalla Vecchia L, Porta A. Characterization of the Asymmetry of the Cardiac and Sympathetic Arms of the Baroreflex From Spontaneous Variability During Incremental Head-Up Tilt. Front Physiol. 2019 Apr 2;10:342. doi: 10.3389/fphys.2019.00342. PMID: 31001137; PMCID: PMC6454064.   This is the abstract: Hysteresis of the baroreflex (BR) is the result of the different BR sensitivity (BRS) when arterial pressure (AP) rises or falls. This phenomenon has been poorly studied and almost exclusively examined by applying pharmacological challenges and static approaches disregarding causal relations. This study inspects the asymmetry of the cardiac BR (cBR) and vascular sympathetic BR (sBR) in physiological closed loop conditions from spontaneous fluctuations of physiological variables, namely heart period (HP) and systolic AP (SAP) leading to the estimation of cardiac BRS (cBRS) and muscle sympathetic nerve activity (MSNA) and diastolic AP (DAP) leading to the estimation of vascular sympathetic BRS (sBRS). The assessment was carried out in 12 young healthy subjects undergoing incremental head-up tilt with table inclination gradually increased from 0 to 60°. Two analytical methods were exploited and compared, namely the sequence (SEQ) and phase-rectified signal averaging (PRSA) methods. SEQ analysis is based on the detection of joint causal schemes representing the HP and MSNA burst rate delayed responses to spontaneous SAP and DAP modifications, respectively. PRSA analysis averages HP and MSNA burst rate patterns after aligning them according to the direction of SAP and DAP changes, respectively. Since cBRSs were similar when SAP went up or down, hysteresis of cBR was not detected. Conversely, hysteresis of sBR was evident with sBRS more negative when DAP was falling than rising. sBR hysteresis was no longer visible during sympathetic activation induced by the orthostatic challenge. These results were obtained via the SEQ method, while the PRSA technique appeared to be less powerful in describing the BR asymmetry due to the strong association between BRS estimates computed over positive and negative AP variations. This study suggests that cBR and sBR provide different information about the BR control, sBR exhibits more relevant non-linear features that are evident even during physiological changes of AP, and the SEQ method can be fruitfully exploited to characterize the BR hysteresis with promising applications to BR branches different from cBR and sBR.

Data set from De Maria B, Bari V, Sgoifo A, Carnevali L, Cairo B, Vaini E, Catai AM, de Medeiros Takahashi AC, Dalla Vecchia LA, Porta A. Concomitant Evaluation of Heart Period and QT Interval Variability Spectral Markers to Typify Cardiac Control in Humans and Rats. Front Physiol. 2019 Nov 29;10:1478. doi: 10.3389/fphys.2019.01478. PMID: 31849718; PMCID: PMC6897045.

Data set from De Maria B, Bari V, Sgoifo A, Carnevali L, Cairo B, Vaini E, Catai AM, de Medeiros Takahashi AC, Dalla Vecchia LA, Porta A. Concomitant Evaluation of Heart Period and QT Interval Variability Spectral Markers to Typify Cardiac Control in Humans and Rats. Front Physiol. 2019 Nov 29;10:1478. doi: 10.3389/fphys.2019.01478. PMID: 31849718; PMCID: PMC6897045.   This is the abstract: The variability of heart period, measured as the time distance between two consecutive QRS complexes from the electrocardiogram (RR), was exploited to infer cardiac vagal control, while the variability of the duration of the electrical activity of the heart, measured as the time interval from Q-wave onset to T-wave end (QT), was proposed as an indirect index of cardiac sympathetic modulation. This study tests the utility of the concomitant evaluation of RR variability (RRV) and QT variability (QTV) markers in typifying cardiac autonomic control of humans under different experimental conditions and of rat groups featuring documented differences in resting sympatho-vagal balance. We considered: (i) 23 healthy young subjects in resting supine position (REST) undergoing head-up tilt at 45° (T45) and 90° (T90) followed by recovery to the supine position; (ii) 9 Wistar (WI) and 14 wild-type Groningen (WT) rats in unstressed conditions, where the WT animals were classified as non-aggressive (non-AGG, n = 9) and aggressive (AGG, n = 5) according to the resident intruder test. In humans, spectral analysis of RRV and QTV was performed over a single stationary sequence of 250 consecutive values. In rats, spectral analysis was iterated over 10-min recordings with a frame length of 250 beats with 80% overlap and the median of the distribution of the spectral markers was extracted. Over RRV and QTV we computed the power in the low frequency (LF, from 0.04 to 0.15 Hz in humans and from 0.2 to 0.75 Hz in rats) band (LFRR and LFQT) and the power in the high frequency (HF, from 0.15 to 0.5 Hz in humans and from 0.75 to 2.5 Hz in rats) band (HFRR and HFQT). In humans the HFRR power was lower during T90 and higher during recovery compared to REST, while the LFQT power was higher during T90. In rats the HFRR power was lower in WT rats compared to WI rats and the LFQT power was higher in AGG than in non-AGG animals. We concluded that RRV and QTV provide complementary information in describing the functioning of vagal and sympathetic limbs of the autonomic nervous system in humans and rats.

Data set from De Maria B, Bari V, Cairo B, Vaini E, Martins de Abreu R, Perseguini NM, Milan-Mattos J, Rehder-Santos P, Minatel V, Catai AM, Dalla Vecchia LA, Porta A. Cardiac baroreflex hysteresis is one of the determinants of the heart period variability asymmetry. Am J Physiol Regul Integr Comp Physiol. 2019 Oct 1;317(4):R539-R551. doi: 10.1152/ajpregu.00112.2019. Epub 2019 Jul 31. PMID: 31365303.

Data set from De Maria B, Bari V, Cairo B, Vaini E, Martins de Abreu R, Perseguini NM, Milan-Mattos J, Rehder-Santos P, Minatel V, Catai AM, Dalla Vecchia LA, Porta A. Cardiac baroreflex hysteresis is one of the determinants of the heart period variability asymmetry. Am J Physiol Regul Integr Comp Physiol. 2019 Oct 1;317(4):R539-R551. doi: 10.1152/ajpregu.00112.2019. Epub 2019 Jul 31. PMID: 31365303.   This is the abstact: In heart period (HP) variability (HPV) recordings the percentage of negative HP variations tends to be greater than that of positive ones and this pattern is referred to as HPV asymmetry (HPVA). HPVA has been studied in several experimental conditions in healthy and pathological populations, but its origin is unclear. The baroreflex (BR) exhibits an asymmetric behavior as well given that it reacts more importantly to positive than negative arterial pressure (AP) variations. We tested the hypothesis that the BR asymmetry (BRA) is a HPVA determinant over spontaneous fluctuations of HP and systolic AP (SAP). We studied 100 healthy subjects (age from 21 to 70 yr, 54 men) comprising 20 subjects in each age decade. Electrocardiogram and noninvasive AP were recorded for 15 min at rest in supine position (REST) and during active standing (STAND). The HPVA was evaluated via Porta's index and Guzik's index, while the BRA was assessed as the difference, and normalized difference, between BR sensitivities computed over positive and negative SAP variations via the sequence method applied to HP and SAP variability. HPVA significantly increased during STAND and decreased progressively with age. BRA was not significantly detected both at REST and during STAND. However, we found a significant positive association between BRA and HPVA markers during STAND persisting even within the age groups. This study supports the use of HPVA indexes as descriptors of BRA and identified a challenge soliciting the BR response like STAND to maximize the association between HPVA and BRA mar

Data set from the article Cairo B, De Maria B, Bari V, Vaini E, Heusser K, Tank J, Jordan J, Barbic F, Furlan R, Marinou K, Dalla Vecchia L, Porta A. Information-domain method for the quantification of the complexity of the sympathetic baroreflex regulation in healthy subjects and amyotrophic lateral sclerosis patients. Physiol Meas. 2019 Apr 4;40(3):034004. doi: 10.1088/1361-6579/ab0d4b. PMID: 30840931.

Data set from the article Cairo B, De Maria B, Bari V, Vaini E, Heusser K, Tank J, Jordan J, Barbic F, Furlan R, Marinou K, Dalla Vecchia L, Porta A. Information-domain method for the quantification of the complexity of the sympathetic baroreflex regulation in healthy subjects and amyotrophic lateral sclerosis patients. Physiol Meas. 2019 Apr 4;40(3):034004. doi: 10.1088/1361-6579/ab0d4b. PMID: 30840931. this is the abstract: Background: The sympathetic baroreflex (sBR) adjusts muscle sympathetic nerve activity (MSNA) in response to arterial pressure changes but the relevance of assessing sBR control complexity is unclear. Objective: We propose a method for the evaluation of sBR control complexity. Approach: The approach comprises the quantification of complexity of the sBR latency regulation and the assessment of complexity of the relationship linking MSNA burst to R-wave peak regardless of the variability of the sBR latency. The Shannon entropy (SE) of the sBR latency distribution is taken as an estimate of complexity of the sBR latency regulation. The conditional entropy (CE) of the beat-to-beat binary series obtained by coding the presence/absence of the MSNA burst after an R-wave peak is taken as an estimate of complexity of the sBR control regardless of the sBR latency variability. Surrogate analysis was utilized to set the level of inactive or impaired sBR. The approach was applied to 10 young healthy subjects undergoing head-up tilt (HUT) followed by lower body negative pressure to evoke presyncope (preSYNC) before and after 21 d head-down bed rest (HDBR), and to five amyotrophic lateral sclerosis (ALS) patients undergoing HUT. Main results: In healthy subjects the surrogate analysis suggested that HUT and preSYNC significantly activated the sBR control but its response was weakened after 21 d HDBR. During preSYNC sBR latency increased significantly only after 21 d HDBR. In ALS patients the complexity of the sBR latency regulation was close to the level set by surrogate analysis and HUT did not trigger any sBR control response. Significance: The proposed method for sBR control complexity quantification was useful in detecting the impairment of the sBR control after 21 d HDBR in healthy subjects and the dysfunction of the sBR regulation in ALS patients.

Data set from the article Bari V, Vaini E, Pistuddi V, Fantinato A, Cairo B, De Maria B, Ranucci M, Porta A. Short-term multiscale complexity analysis of cardiovascular variability improves low cardiac output syndrome risk stratification after coronary artery bypass grafting. Physiol Meas. 2019 Apr 26;40(4):044001. doi: 10.1088/1361-6579/ab12f0. PMID: 30909175.

Data set from the article Bari V, Vaini E, Pistuddi V, et al. Short-term multiscale complexity analysis of cardiovascular variability improves low cardiac output syndrome risk stratification after coronary artery bypass grafting. Physiol Meas. 2019;40(4):044001. Published 2019 Apr 26. doi:10.1088/1361-6579/ab12f0 This is the abstract: Background: Low cardiac output syndrome (LCOS) is a myocardial dysfunction leading to systemic hypoperfusion, favored by particular conditions of the autonomic nervous system. LCOS is one of the adverse events that might occur after cardiac surgery. Objective: The aim is to test the hypothesis that short-term multiscale complexity (MSC) analysis of heart period (HP) and systolic arterial pressure (SAP) variability series in the frequency bands typical of cardiovascular control could be fruitfully exploited in identifying subjects at risk of developing LCOS after coronary artery bypass graft (CABG). Approach: HP and SAP beat-to-beat series were derived from electrocardiogram (ECG) and invasive arterial pressure (AP) signal acquired in 128 patients scheduled for CABG before (PRE) and after (POST) the induction of general anesthesia with propofol and remifentanil. Subjects were labeled as LCOS (n = 14) and noLCOS (n = 114) according to the LCOS development. MSC markers were calculated as the complement to 1 of the modulus of the average position of the poles dropping in the low-frequency (LF, 0.04-0.15 Hz) and high-frequency (HF, 0.15-0.5 Hz) bands as derived from the autoregressive model of HP and SAP series. Traditional time and frequency domain indexes were also calculated. Main results: Traditional parameters were able to assess the depression of the cardiovascular regulation induced by general anesthesia, but showed weak performances in differentiating LCOS and noLCOS groups. Conversely, HP complexity in LF band and SAP complexity in HF band assessed during POST remained associated with LCOS even after entering a multivariate logistic regression model adjusted for clinical and demographic factors. Significance: The MSC approach can be fruitfully applied to improve risk stratification for LCOS after CABG likely because MSC markers describe the dysfunction of the sympathetic control and the impairment of the mechanical properties of the heart in the LCOS group.

Data set from the article Vaini E, Bari V, Fantinato A, Pistuddi V, Cairo B, De Maria B, Ranucci M, Porta A. Causality analysis reveals the link between cerebrovascular control and acute kidney dysfunction after coronary artery bypass grafting. Physiol Meas. 2019 Jul 1;40(6):064006. doi: 10.1088/1361-6579/ab21b1. PMID: 31091519.

Data set from the article Vaini E, Bari V, Fantinato A, et al. Causality analysis reveals the link between cerebrovascular control and acute kidney dysfunction after coronary artery bypass grafting. Physiol Meas. 2019;40(6):064006. Published 2019 Jul 1. doi:10.1088/1361-6579/ab21b1 This is the abstract: Background: Patients undergoing coronary artery bypass graft (CABG) surgery might experience postoperative complications and some of them, such as acute kidney dysfunction (AKD), are the likely consequence of hypoperfusion. We hypothesized that an impaired cerebrovascular control is a hallmark of a vascular damage that might favor AKD after CABG. Objective: Our aim is to characterize cerebrovascular control in CABG patients through the assessment of the relationship between mean arterial pressure (MAP) and mean cerebral blood flow velocity (MCBFV) and to check whether markers describing MCBFV-MAP dynamical interactions could identify subjects at risk to develop postoperative AKD. Approach: MAP and MCBFV beat-to-beat series were extracted from invasive arterial pressure and transcranial Doppler recordings acquired simultaneously in 23 patients just before CABG after the induction of propofol general anesthesia. Subjects were divided into AKD group (n = 9, age: 68 ± 9, 8 males) and noAKD group (n = 14, age: 65 ± 8, 12 males) according to whether they developed postoperative AKD or not after CABG. We computed MAP and MCBFV time-domain and spectral markers as well as MCBFV-MAP cross-spectral indexes in very-low-frequency (VLF, 0.02-0.07 Hz), low-frequency (LF, 0.07-0.15 Hz) and high-frequency (HF, 0.15-0.30 Hz) bands. We also calculated model-based transfer entropy (TE) to quantify the degree of MCBFV dependence on MAP and vice versa. The null hypothesis of MCBFV-MAP uncoupling was tested via a surrogate approach associating MAP and MCBFV in different patients. Main results: Time, spectral and cross-spectral markers had a limited power in separating AKD from noAKD individuals. Conversely, TE from MAP to MCBFV was significantly above the level set by surrogates only in AKD groups and significantly larger than that computed in noAKD. Significance: The reduced cerebrovascular autoregulation in AKD patients suggest a vascular impairment likely making them more at risk of hypoperfusion during CABG and AKD after CABG.

Data set from Barbic F, Minonzio M, Cairo B, Shiffer D, Dipasquale A, Cerina L, Vatteroni A, Urechie V, Verzeletti P, Badilini F, Vaglio M, Iatrino R, Porta A, Santambrogio M, Gatti R, Furlan R. Effects of different classroom temperatures on cardiac autonomic control and cognitive performances in undergraduate students. Physiol Meas. 2019 Jun 4;40(5):054005. doi: 10.1088/1361-6579/ab1816. PMID: 30970334.

Data set from Barbic F, Minonzio M, Cairo B, Shiffer D, Dipasquale A, Cerina L, Vatteroni A, Urechie V, Verzeletti P, Badilini F, Vaglio M, Iatrino R, Porta A, Santambrogio M, Gatti R, Furlan R. Effects of different classroom temperatures on cardiac autonomic control and cognitive performances in undergraduate students. Physiol Meas. 2019 Jun 4;40(5):054005. doi: 10.1088/1361-6579/ab1816. PMID: 30970334.   This is the abstract: Objective: Indoor microclimate may affect students' wellbeing, cardiac autonomic control and cognitive performance with potential impact on learning capabilities. To assess the effects of classroom temperature variations on the autonomic profile and students' cognitive capabilities. Approach: Twenty students attending Humanitas University School, (14M, age 21 ± 3 years) underwent a single-lead ECG continuous recording by a portable device during a 2 h lecture when classroom temperature was set 'neutral' (20 °C-22 °C, Day 1) and when classroom temperature was set to 24 °C-26 °C (Day 2). ECGs were sent by telemetry to a server for off-line analysis. Spectral analysis of RR variability provided indices of cardiac sympathetic (LFnu), vagal (HF, HFnu) and cardiac sympatho-vagal modulation (LF/HF). Symbolic analysis of RR variability provided the percentage of sequences of three heart periods with no significant change in RR interval (0V%) and with two significant variations (2V%) reflecting cardiac sympathetic and vagal modulation, respectively. Students' cognitive performance (memory, verbal comprehension and reasoning) was assessed at the end of each lecture using the Cambridge Brain Sciences cognitive evaluation tool. Main results: Classroom temperature and CO2 were assessed every 5 min. Classroom temperatures were 22.4 °C ± 0.1 °C (Day 1) and 26.2 °C ± 0.1 °C (Day 2). Student's thermal comfort was lower during Day 2 compared to Day 1. HR, LF/HF and 0V% were greater during Day 2 (79.5 ± 12.1 bpm, 6.9 ± 7.1 and 32.8% ± 10.3%) than during Day 1 (72.6 ± 10.8 bpm, 3.4 ± 3.7, 21.4% ± 9.2%). Conversely, 2V% was lower during Day 2 (23.1% ± 8.1%) than during Day 1 (32.3% ± 11.4%). Short-term memory, verbal ability and the overall cognitive C-score scores were lower during Day 2 (10.3 ± 0.3; 8.1 ± 1.2 and 10.9 ± 2.0) compared to Day 1 (11.7 ± 2.1; 10.7 ± 1.7 and 12.6 ± 1.8). Significance: During Day 2, a shift of the cardiac autonomic control towards a sympathetic predominance was observed compared to Day 1, in the presence of greater thermal discomfort. Furthermore, during Day 2 reduced cognitive performances were found.

Data set from Dalla Vecchia LA, Barbic F, De Maria B, Cozzolino D, Gatti R, Dipaola F, Brunetta E, Zamuner AR, Porta A, Furlan R. Can strenuous exercise harm the heart? Insights from a study of cardiovascular neural regulation in amateur triathletes. PLoS One. 2019 May 7;14(5):e0216567. doi: 10.1371/journal.pone.0216567. PMID: 31063482; PMCID: PMC6504093.

Data set from Dalla Vecchia LA, Barbic F, De Maria B, Cozzolino D, Gatti R, Dipaola F, Brunetta E, Zamuner AR, Porta A, Furlan R. Can strenuous exercise harm the heart? Insights from a study of cardiovascular neural regulation in amateur triathletes. PLoS One. 2019 May 7;14(5):e0216567. doi: 10.1371/journal.pone.0216567. PMID: 31063482; PMCID: PMC6504093   This is the abstract: Regular exercise is recommended to improve the cardiovascular risk profile. However, there is growing evidence that extreme volumes and intensity of long-term exertion may increase the risk of acute cardiac events. The aim of this study is to investigate the after-effects of regular, strenuous physical training on the cardiovascular neural regulation in a group of amateur triathletes compared to age-matched sedentary controls. We enrolled 11 non-elite triathletes (4 women, age 24±4 years), who had refrained from exercise for 72 hours, and 11 age-matched healthy non-athletes (3 women, age 25±2 years). Comprehensive echocardiographic and cardiopulmonary exercise tests were performed at baseline. Electrocardiogram, non-invasive blood pressure, respiratory activity, and muscle sympathetic nerve activity (MSNA) were continuously recorded in a supine position (REST) and during an incremental 15° step-wise head-up tilt test up to 75° (TILT). Blood samples were collected for determination of stress mediators. Autoregressive spectral analysis provided the indices of the cardiac sympathetic (LFRR) and vagal (HFRR) activity, the vascular sympathetic control (LFSAP), and the cardiac sympatho-vagal modulation (LF/HF). Compared to controls, triathletes were characterized by greater LFRR, LF/HF ratio, LFSAP, MSNA, and lower HFRR at REST and during TILT, i.e. greater overall cardiovascular sympathetic modulation together with lower cardiac vagal activity. Cortisol and adrenocorticotropic hormone concentrations were also higher in triathletes. In conclusion, triathletes were characterized by signs of sustained cardiovascular sympathetic overactivity. This might represent a risk factor for future cardiovascular events, given the known association between chronic excessive sympathetic activity and increased cardiovascular risk.