Higher Heart Research Articles

Progressive overload in cardiorespiratory exercise training for young and old: Is increasing duration or intensity of exercise more important?

People undertake endurance training to improve their health and cardio-respiratory fitness. Subsequent cardio-respiratory and skeletal muscle aerobic metabolic adaptations are gauged by improvements in maximum or peak oxygen uptake (V̇O2peak) and the blood lactate inflection point or threshold during incremental exercise – (LIP). To further improve physiological capability, subsequent homoeostatic disturbances from exercise should be progressively greater in succeeding exercise sessions. Therefore, exercise duration, frequency or intensity should be progressively increased during a training regimen to ensure adaptation potential is realized. A progressive increase in training workload is termed “progressive overload”. Despite the universal acknowledgment of the importance of progressive overload, it is unclear if systematically progressing altering either exercise intensity or duration (or distance covered) affect cardio-respiratory gains differently in young and older populations. As running faster results in higher heart rates and greater skeletal muscle metabolic stress than running the same distance at a lower speed, in this hypothesis we postulate that progressively increasing exercise run intensity will result in greater mean and higher incidence of V̇O2peak and LIP gains in young adults (<50 years). However, the mechanisms that initiate improvements in cardio-respiratory fitness and skeletal muscle aerobic function may be different in older adults due to the inevitable aging decline in cardio-vascular function and mechanical and morphological properties of muscle–tendon units. In older adults (>60 years) we hypothesize progressively increasing run distance while maintaining the same speed will just be as effective as to progressively increasing speed to improve V̇O2peak and LIP. To test these hypotheses, we propose a study that compares progressively increasing run intensity to a treatment of progressive matched run distance where speed remains constant in young and old adults.

Low left ventricular outflow tract velocity time integral predicts normotensive shock in patients with acute pulmonary embolism

Abstract Funding Acknowledgements None. Introduction In patients with intermediate-risk acute pulmonary embolism (PE) outcomes vary widely, with mortality rates ranging from 3-15% and rates of normotensive shock up to 30%.1-3 Current risk models don't fully capture those at higher risk and identify patients who may benefit from advanced therapies. The left ventricular outflow tract (LVOT) velocity time integral (VTI), a surrogate marker of cardiac output, has been associated with increased mortality in acute PE.4 Our objective was to determine the association between LVOT VTI and its predictive value in identifying normotensive shock in this patient population. Methods Patients who underwent percutaneous mechanical thrombectomy (MT) between August 2020 and March 2023 at a large academic public hospital were considered for the study. Inclusion criteria comprised of normotensive patients (SBP ≥ 90 mmHg) with invasive measures of cardiac index (CI). VTI was obtained by pulsed wave doppler at the LVOT in either the apical 3 or apical 5 chamber view. The primary outcome was the association between LVOT VTI and normotensive shock and a cut off of 15 cm was used to examine this association based on prior studies.4 Results A total of 49 patients with intermediate-risk PE underwent MT, 16 patients had incomplete data, resulting in a final cohort of 33 patients (mean age: 57 ± 13yrs; 38% female). Patients with LVOT VTI of &amp;lt;15 cm were younger (53 vs 62 years p=0.02), had lower systolic blood pressure at presentation (122 vs 134 mmHg, p=0.047), higher heart rate (112.6 vs 96.2 beats/min, p=0.008), a higher composite shock score (CPES) (5 vs 3, p=0.012), lower cardiac index (1.9 vs 3.1 L/min/m2, p&amp;lt;0.001), a higher PASP (61.4 vs 48.9 mmHg, p=0.018), and higher rates of elevated lactate (90% vs 42%, p=0.027). LVOT VTI threshold of &amp;lt;15cm effectively identified patients with normotensive shock (90% vs 8% p&amp;lt;0.001). There was no statistically significant difference in the rates of saddle emboli, left ventricular ejection fraction, sPESI and BOVA scores in patients with VTI above or below 15cm. In patients with normotensive shock, 19/20 (95%) had LVOT VTI ≤ 15cm with a median of 13 cm (IQR 12, 14) (Figure). In patients without normotensive shock, 11/13 (84%) had LVOT VTI &amp;gt;15 with a median of 18 (IQR 17, 21). The area under the curve for LVOT VTI ≤ 15 cm in predicting normotensive shock was 0.89. The sensitivity and specificity of LVOT VTI ≤ 15 cm in predicting normotensive shock was 91.6% and 90.4% respectively. Conclusion Our study suggests that LVOT VTI is a reliable surrogate for cardiac output in patients with acute PE and can effectively identify those in the intermediate-risk group who are at risk for normotensive shock. A LVOT VTI &amp;lt;15cm may identify intermediate-risk patients at higher risk for hemodynamic decompensation and further studies are needed to evaluate whether these patients would benefit from upfront catheter-based therapies.

McConnell's sign predicts normotensive shock in patients with acute pulmonary embolism

Abstract Funding Acknowledgements None. Background Patients with intermediate-risk acute pulmonary embolism (PE) have mortality rates ranging from 3-15%, with incidence of normotensive shock occurring in up to 30% of patients.1-3 Existing risk models often fall short in accurately identifying those at heightened risk of normotensive shock and those who might derive benefit from advanced therapeutic interventions including catheter based therapies. Diagnosis of normotensive shock typically necessitates invasive right heart catheterization, however, McConnell's sign has been associated with higher risk PEs.4 Consequently, our objective was to assess the relationship between McConnell's sign, a readily available bedside point-of-care tool, and its predictive value in identifying normotensive shock in patients diagnosed with acute intermediate-risk PE. Methods All patients with intermediate-risk PE who underwent percutaneous mechanical thrombectomy (MT) between August 2020 and April 2023 at a large academic public hospital were included in the study. Normotensive shock was defined as patients with systolic blood pressure (SBP) ≥ 90mmHg in the absence of vasopressor support with pre-procedural invasive measures of CI £ 2.2 L/min/m2 and clinical evidence of hypoperfusion (i.e. elevated lactate, oliguria). The primary outcome was the association between McConnell’s sign and normotensive shock. Results A total of 49 patients with intermediate-risk PE underwent MT, 9 patients had incomplete data, resulting in a final cohort of 40 patients (mean age: 57 ± 13 years; 45% female). A total of 29/40 (72.5%) patients had McConnell’s sign. Patients with McConnell’s sign had higher rates of obesity (59% vs 18% p=0.02), higher heart rate (114 vs 99 beats/min, p=0.008), higher rates of elevated lactate (86% vs 55%, p=0..038), lower cardiac index (1.9 vs 3.1 L/min/m2, p=0.003), and higher rates of normotensive shock (76% vs 27%, p=0.005). There was no statistically significant difference in age, sex, race, rates of saddle emboli, left ventricular ejection fraction, pulmonary artery systolic pressure, presenting blood pressure, sPESI and composite pulmonary embolism shock score scores in patients with or without McConnell’s sign. In patients with normotensive shock, 22/25 (88%) had McConnell’s sign and only 53.3% had McConnell’s sign without shock (Figure 1). Patients with McConnell’s sign had an increased odds (OR 8.38, CI: 1.73-40.53; p=0.008, AUC 0.70, 95% CI: 0.56-0.85) of normotensive shock. Conclusion This is the first study to suggest that McConnell’s sign can effectively identify those in the intermediate-risk group who are at risk for normotensive shock. Further studies are needed to validate this non-invasive technique that can be rapidly performed at bedside with high reproducibility and whether it can help risk-stratify patients who may benefit from advanced PE therapies.

The role of rhythm control in patients with first diagnosed atrial fibrillation in a real world collective

Abstract Funding Acknowledgements Type of funding sources: Private company. Main funding source(s): Daiichi Sankyo Bayer. Background There has been conflicting evidence regarding the importance of rhythm control as opposed to rate control in patients with atrial fibrillation (AF). Thus, no clear recommendation on early rhythm control for risk reduction is given in the current guidelines. However, some evidence suggests that rhythm control is superior to rate control in patients with a recent diagnosis of AF. Purpose We aim to characterize patients with first diagnosed AF and evaluate the effect of a rhythm control strategy at the time of diagnosis on long term cardiovascular outcomes. Methods This is a single center, retrospective observational sub study based as a part of the HERA-FIB project. HERA-FIB included 10.222 patients presenting to the emergency department (ED) of the department of cardiology of a university hospital from June 2009 to March 2020. We consecutively included all patients with a history AF or current AF upon presentation, regardless of the reason for presentation. A structured follow-up regarding survival and major cardiovascular events was performed. Mean follow up was 23 months (IQR 12-35). Patient care was not influenced. The project was performed according to the declaration of Helsinki and was approved by the local ethics committee and registered at ClinicalTrials.gov (Identifier: NCT05995561). Results. After adjudication we included 10.222 patients in this study. Of those 2758 (27%) had no previous history of AF and were first diagnosed with AF upon presentation. There were major differences in baseline characteristics as patients with first diagnosed AF were younger (73 years vs 76 years, p&amp;lt;0.0001), showed a normal left ventricular function more often (47.9% vs 40.2%, p&amp;lt;0.0001) and had fewer histories of coronary artery disease (CAD) (30.2% vs 48.0%, p&amp;lt;0.0001) and fewer histories of stroke or transient ischemic attack (TIA) (9.0% vs 14.0%, p&amp;lt;0.0001). In contrast they had higher heart rates (113 bpm vs 84 bpm, p&amp;lt;0.0001) on admission. Among the patients with first diagnosed AF 24.6% received a cardioversion (either pharmacological of electrical). Patients with first diagnosed AF undergoing rhythm control treatment showed lower rates for all-cause mortality (10.4% vs 18.2%, p&amp;lt;0.0001) and myocardial infarction (2.4% vs. 5.2%, p=0.0045) as compared to patients first diagnosed with AF not recieving a cardioversion. However, no differences for strokes (2.7% vs 3.3%, p=0.6158) or severe bleeding according to ISTH major bleeding criteria (4.0% vs. 5.3%, p=0.2252) could be detected. Conclusions Patients presenting to an ED with first diagnosed AF are younger and show fewer comorbidities compared to patients with pre-existing AF. Patients with first diagnosed AF seem to profit from early rhythm control strategies showing a reduction for the rates of all-cause mortality and myocardial infarction. However, no difference for stroke or major bleeding events could be detected. Additional, prospective studies are required to verify this hypothesis.

SPECIAL ISSUE: Male-Female Differences in Psychophysiological Stress Profiles Before and After a Group Relaxation/Biofeedback Stress Management Program

This study used stress profiles to assess whether a biofeedback-assisted stress management program that previously documented decreased anxiety, stress symptoms, medication use, and increased well-being also had physiological effects. Psychophysiological stress profiles are used in quantifying an individual’s responses under stress and during recovery from stressors by looking at their degree of response, pattern of response, and degree of recovery. A stress profile measuring surface electromyography (sEMG), heart rate, and skin temperature was performed on 141 adults before and after their participation in a group relaxation and stress management program. After 10 sessions of skills training, the only significant change in physical parameters was warmer hand temperatures in both males and females. Temperature was also the only modality that was included as biofeedback training within the program. Trait anxiety (STAI) was significantly positively correlated with females’ sEMG before and after the program. Females had significantly colder hands, higher heart rate, and a pattern of higher sEMG than males did throughout all profiles. The responses and recovery from different stressors showed some significant male-female differences. Future psychophysiological and psychological studies should further investigate male-female differences.

Порівняльний аналіз субклінічного тривожно-депресивного синдрому в пацієнтів із гострим інфарктом міокарда з елевацією сегмента ST до та під час активних бойових дій у Харківській області

The aim – to assess subclinical emotional distress in patients with ST-Elevation Myocardial Infarction (STEMI) before and during the ongoing conflict in the Kharkiv Region. Materials and methods. The study encompassed 242 patients exhibiting subclinical emotional distress and hospitalized with STEMI at «L.T. Malaya TNI of NAMSU» before active conflict, compared with 65 patients during the conflict. Adherence to ethical standards was ensured, in line with the 1964 Helsinki Declaration, and the protocol received approval from the local ethics committee (Protocol № 8, dated 29.08.2016, and Protocol № 4, dated 12.05.2022). Participants completed the DASS-21 questionnaire, reflecting their emotional state 10–14 days prior, and received STEMI treatment as per current guidelines.Results. We showed that anxiety more frequent appeared during the active hostilities (p=0.0218). Depression had the influence on excessive smoking (p=0.0199), LV EF decrease (p=0.0057), LDL-C increase (p=0.0393). Anxiety and stress intrude into hypertension frequency (p=0.0171, p=0.0489) consequently as well as anxiety – on LDL-C increase (p=0.0068). All data of subclinical emotional distress during active hostilities associate with the frequency of smoking increase: p=0.0422 for depression, p=0.0275 for anxiety and p=0.0199 for stress. Depression associates with LVEF decrease (p=0.0267), the leucocytes count increase (p=0.0467), high frequency of hypertension (p=0.0410). Anxiety associates with higher heart rate (p=0.0277), depression and stress – with younger age (p=0.0369).Conclusions. Our research demonstrates close associations between the data of subclinical emotional distress both in patients with STEMI before and during the active hostilities in Kharkiv Region. Data were assessed with DASS-21 questionnaire on 10 –14 day prior the event. These results should be undertaken during general practitioner’s appointment to prevent further cardiovascular event.

Effects of gestational intermittent hypoxia on the autoresuscitation response following anoxia-induced apneas in neonatal mice

Introduction: Sudden infant death syndrome (SIDS) is the leading cause of death in infants from one month to one year of age. Smoking is a significant risk factor in SIDS, and smoking probably causes intermittent hypoxia in the fetus. Therefore, we modeled the effects of intermittent hypoxia during gestation in mice to determine if gestational intermittent hypoxia would adversely affect the capacity of neonatal mice to autoresuscitate effectively after exposure to anoxic stimuli. A degraded capacity to autoresuscitate could explain, in part, why infants born to mothers who smoke have an increased risk of dying from of SIDS. The primary objective of this study was to investigate the effects of intermittent gestational hypoxia on the autoresuscitation responses to anoxia-induced apneas in neonatal mice. Our hypothesis was that pups born to intermittently hypoxic dams would struggle more to recover from anoxic apneas — would have impaired cardiorespiratory responses to anoxic stress compared to the control mice born to dams exposed to room air during gestation. Methods: We studied C57Bl/6 dams who previously had one litter to prove their capability to breed and rear pups. Dams were placed in either an hypoxic or room air chamber at approximately embryonic day 5 (E5; fifth day of pregnancy). The fractional inspired oxygen concentration (FIO2) was reduced to 11% for 10 minutes, three times per hour, with 10 minute periods of 21% oxygen between them. Each hour of intermittent hypoxia was followed by an hour breathing 21% FiO2. The room air control chamber was maintained at a constant FIO2 of 21% with inflows of compressed air that mimicked the noise and flow of nitrogen in the hypoxic chamber. The dams spent the entirety of their pregnancies in the environmental chambers. Once the pups were delivered, the cages were placed in room air, housing environments. The pups were allowed to stay with their mothers until approximately post-natal day 8 (P8). On P8, each pup was fitted into a head out plethysmograph to measure respiratory flow using a pneumotachograph. We recorded respiratory activity, ECG activity, and body movements (using a piezo sensitive film). The pups were maintained at ~34 degrees C in the pneumotachographic chamber. We measured the highest respiratory rate, highest heart rate, longest apnea, gasp latency, mean heart rate recovery, and mean respiratory rate recovery. Results: The mean heart rate recovery and mean longest apnea (in seconds) doubled in the mice exposed to gestational intermittent hypoxia compared to pups born to dams exposed to room air during gestation. The mean heart rate recovery and mean longest apnea in gestationally hypoxic pups was 41.0 +/- 13.7 seconds and 22.05 +/- 12.0 seconds, respectively. The mean heart rate recovery and mean longest apnea in normal, room air-exposed pups was 22.4 +/- 11.1 seconds and 10.3 +/- 7.0 seconds, respectively. The longest apnea in gestational intermittent hypoxic pups was significantly longer than in control pups (53.0 +/- 13.7 seconds and 19.1 +/- 15.0 seconds). Pups exposed to gestational intermittent hypoxia also had increased mean respiratory rate recovery times and gasp latency times (start of apnea until the first gasp). The average body weight of hypoxic pups was 4.3 grams while the average body weight for the normal pups was 4.9 grams. Conclusion: Gestational intermittent hypoxia was associated with delayed and prolonged the autoresuscitation responses in neonatal mice following acute anoxic exposure. We hypothesize that this is due to changes in the brain’s serotonin system. We are investigating how intrauterine hypoxia may decrease serotonin and serotonergic signaling pathways as changes in serotonergic function may degrade the capacity of mice to autoresuscitate following anoxic gas exposure. NIH/NICHD. HD100823 and NIH/NICHD. HD 107060. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Transgender Women Exhibit a Distinct Stress Echocardiography Profile Compared With Age-Matched Cisgender Counterparts: The Mayo Clinic Women’s Heart Clinic Experience

Stress echocardiographic (SE) testing is an important modality in cardiovascular risk stratification and obstructive coronary artery disease assessment. Binary sex-based parameters are classically used for the interpretation of these studies, even among transgender women (TGW). Coronary artery disease is a leading cause of morbidity and mortality in this population. Yet, it remains unclear whether TGW exhibit a distinct stress testing profile from their cisgender counterparts. Using a matched case-control study design, the authors compared the echocardiographic stress testing profiles of TGW (n=43) with those of matched cisgender men (CGM; n=84) and cisgender women (CGW; n=86) at a single center. Relevant data, including demographics, comorbidities, and cardiac testing data, were manually extracted from the patients' charts. The prevalence of hypertension and dyslipidemia was similar between TGW and CGW and lower than that of CGM (P=.003 and P=.009, respectively). The majority of comorbidities and laboratory values were similar. On average, TGW had higher heart rates than CGM (P=.002) and had lower blood pressures than CGM and CGW (P<.05). TGW's double product and metabolic equivalents were similar to those among CGW and lower than those of CGM (P=.016 and P=.018, respectively). On echocardiography, left ventricular end-diastolic and end-systolic diameters among TGW were similar to those of CGW but lower than those of CGM (P=.023 and P=.018, respectively). Measures of systolic and diastolic function, except for exercise mitral valve E/e' ratio, which was lower in TGW than CGW (P=.029), were largely similar among the three groups. There was no difference in the wall motion score index, and therefore, no difference in the percentage of positive SE test results. This study shows, for the first time, that TGW have a SE profile that is distinct from that of their cisgender counterparts. Larger, multicenter, prospective studies are warranted to further characterize the SE profile of TGW.

Blunted Brachial Blood Flow Velocity Recovery to Acute Mental Stress in Young Women with PTSD Compared to Controls

Introduction: Post-traumatic stress disorder (PTSD) is a debilitating mental illness associated with increased cardiovascular disease (CVD) risk, a major cause of death among women in the United States. Women are twice as likely as men to develop PTSD after trauma exposure, and cardiovascular reactivity to stress is a known risk factor for CVD. Therefore, our aim was to investigate if young women diagnosed with PTSD will present with impaired hemodynamic responses to acute stress compared to controls. We hypothesized that women with PTSD will have high blood pressure (BP), heart rate (HR) and blood flow velocity (BFV) response to a mental stress protocol, and a blunted recovery. Methods: We recruited for this study ten young women with PTSD and nine trauma-exposed women without PTSD (controls) between the ages of 18 to 40 years. We collected data in a single laboratory visit after informed consent and PTSD symptoms severity questionnaire. After demographics and resting hemodynamics, we continuously measured HR using a three-lead EKG, beat-to-beat BP using finger plethysmography and continuous brachial BFV using Doppler ultrasound. A Doppler audio translator was used to transfer the doppler signal in our data analysis software for simultaneous recording of all hemodynamics variables. All variables were recorded during 5 min of supine rest, 5 min of mental stress (via mental arithmetic) and 5 min of recovery. The response and recovery to stress was analyzed using an analysis of covariance with timepoint as within factor and PTSD diagnosis as between-factor. Results: Women with a clinical diagnosis of PTSD had a mean age of 27±10 years and body mass index (BMI) of 30.1±2.9 kg/m2. Controls (trauma-exposed women without PTSD) had a mean age of 26±7 years and body mass index (BMI) of 24± 2.1 kg/m2. Resting seated BP and HR were not different between the groups. The slopes of the overall changes in BFV from baseline to mental stress to recovery were different between young women with PTSD and controls (timepoint*group, P= 0.057) when controlling for PTSD symptoms severity. Specifically, although mental stress elicited similar increases in BFV in women with PTSD (Δ0.80±1.8 cm/sec) and in controls [Δ0.45±1.2 cm/sec, P= 0.44 (timepoint*group)], BFV recovery from stress was impaired in PTSD (Δ0.64±1.3 cm/sec), but not in controls [Δ-2.20±0.84 cm/sec, P= 0.047 (timepoint*group)]. BP and HR reactivity to mental stress and recovery were not different between the groups (P&gt;0.05). Conclusion: The current pilot study revealed that PTSD is associated with blunted recovery from acute mental stress, suggesting early impairment of vascular function in these women at a young age. Young pre-menopausal women are overlooked in prevention strategies and health policies targeting populations at-risk for CVD; with the rising prevalence of trauma exposure in young women, evidence is pointing to a parallel increase in CVD risk. K01HL161027 and UMN CTSI UL1TR002494 No Disclosure. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Mortality rates among adult critical care patients with unusual or extreme values of vital signs and other physiological parameters: a retrospective study.

We evaluated relationships of vital signs and laboratory-tested physiological parameters with in-hospital mortality, focusing on values that are unusual or extreme even in critical care settings. We retrospectively studied Philips Healthcare-MIT eICU data (207 U.S. hospitals, 20142015), including 166,959 adult-patient critical care admissions. Analyzing most-deranged (worst) value measured in the first admission day, we investigated vital signs (body temperature, heart rate, mean arterial pressure, and respiratory rate) as well as albumin, bilirubin, blood pH via arterial blood gas (ABG), blood urea nitrogen, creatinine, FiO2 ABG, glucose, hematocrit, PaO2 ABG, PaCO2 ABG, sodium, 24-hour urine output, and white blood cell count (WBC). In-hospital mortality was ≥50% at extremes of low blood pH, low and high body temperature, low albumin, low glucose, and low heart rate. Near extremes of blood pH, temperature, glucose, heart rate, PaO2 , and WBC, relatively. Small changes in measured values correlated with several-fold mortality rate increases. However, high mortality rates and abrupt mortality increases were often hidden by the common practice of thresholding or binning physiological parameters. The best predictors of in-hospital mortality were blood pH, temperature, and FiO2 (scaled Brier scores: 0.084, 0.063, and 0.049, respectively). In-hospital mortality is high and sharply increasing at extremes of blood pH, body temperature, and other parameters. Common-practice thresholding obscures these associations. In practice, vital signs are sometimes treated more casually than laboratory-tested parameters. Yet, vitals are easier to obtain and we found they are often the best mortality predictors, supporting perspectives that vitals are undervalued.

Exploring Contextual Factors in Vagal Tank Theory

High baseline Heart rate variability (HRV) is a putative measure of resilience which predicts adaptive HRV changes during (Reactivity) and after (Recovery) a stressor according to Vagal Tank Theory. However, we do not understand how the availability of resources prior to a stressor impacts this relationship. Using an ecological framework, we tested VTT hypotheses while examining receptivity to social presence and contemplative practices as a moderator to Reactivity and Recovery during a subsequent stressor. Using ECG, we modeled HRV as the root-mean square of successive R-R intervals (RMSSD) across four conditions: baseline, post contemplative practice, directly before a CO2 breathing tasking, while breathing CO2, and after CO2. Reactivity and Recovery were defined as the usual subtraction for phasic HRV literature, while Receptivity was modeled as post contemplative practice HRV minus baseline. Our multiple regression analyses showed that higher baseline predicted greater reactivity, positively interacting with the female gender and the partner condition (F(9,83)=2.00, p=0.04). Higher baseline predicted lower recovery HRV with no significant interactions (F(9,85)=2.66, R2=0.22, p=0.009), potentially due to the benefit in the HRV level at the reference level (after contemplative practice). Higher receptivity predicted higher recovery, with women showing the strongest relationship (F(4,88)=16.3, R2=0.43, p&lt;0.001). Our results suggest that both baseline and receptivity to resources may impact resilience to stress, and that future research should account for gendered effects. Cornell University. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Prevalence and risk factors for isolated systolic hypertension among the oldest-old population in southwestern China: A community-based cross-sectional study.

The prevalence of isolated systolic hypertension (ISH) has doubled between 2002-2005 and 2014 among the oldest-old population in China. However, the prevalence and characteristics of ISH among the oldest-old population in southwestern China remain less known. This study aimed to investigate the prevalence of ISH among the oldest-old population in Chengdu and identify associated factors to provide valuable information for disease etiology and prevention. We recruited 1,312 participants aged over 80 years by using a stratified cluster sampling method between September 2015 and June 2016, from three districts (Jinjiang, Qingyang, and Longquanyi) of Chengdu, the largest city of southwest China. A structured questionnaire, anthropometric data, and blood pressure were collected according to the standard method. Blood pressure was measured three times by using a standardized mercury sphygmomanometer after a 10-minute seated rest. Of 1312 participants, 53.0% (n=695) had ISH. The prevalence of ISH in men and women was 54.7% and 51.3%, respectively, with no significant sex difference (P=.222). The prevalence of ISH increased with advanced age in men (P for trend=0.029), 52.5% for the 80-84 years group, 55.2% for the 85-89 years group, and 70.4% for the 90-98 years group, respectively. Multivariable logistic regression analyses found that drinking (OR=1.85, 95%CI=1.26-2.71), being overweight (OR=1.88, 95%CI=1.19-2.96), and having a higher heart rate (OR=0.66, 95%CI=0.51-0.86) were associated with ISH. Stratified by sex, these three factors remained significant in men. Our work highlights that the burden of ISH is substantial among the oldest-old population in southwestern China.

Effect of series of periodic limb movements in sleep on blood pressure, heart rate and high frequency heart rate variability.

The phenomenon known as periodic limb movements in sleep (PLMS) has been linked to a change in autonomic nervous system (ANS) activity and its effect on circulatory regulation. Autonomic dysfunction or dysregulation in patients with PLMS has been described in some domains; however, any relationship between heart rate variability (HRV) and PLMS has not been clearly established. HRV analysis is a recognised, non-invasive research method that describes the influence of the ANS on heart rate (HR). The aim of our study was to further investigate the dysregulation of autonomic HR control in patients with PLMS. We undertook a retrospective analysis of the polysomnographic (PSG), demographic and medical data of five patients with a total number of 1,348 PLMS. We analysed HR, HRV HF, systolic blood pressure (SBP), and diastolic blood pressure (DBP) for 10 heartbeats before the series of PLMS and 10 consecutive heartbeats as beat-to-beat measurements. The presented method of using successive, short, 10 RR interval segments refers to the time-frequency measurement, which is very clear and useful for presenting changes in the calculated parameters over time and thereby illustrating their dynamics. This method allowed us to assess dynamic changes in HRV HF during successive PLMS series. Statistical analysis was performed using IBM SPSS Statistics (v. 28.0.0.0). The Kruskal-Wallis test was performed to find statistically significant changes from baseline. No statistically significant changes in HR, SBP, or DBP were found in our group, although an increase in the value of the HRV HF was noted, suggesting an increase in intracardiac parasympathetic activity during the subsequent series of PLMS. Our study indicates an increase in parasympathetic activity during the appearance of successive PLMS, which, with the simultaneous lack of changes in HR, may suggest an increase in sympathetic activity, and therefore the appearance of so-called 'autonomic co-activation' resulting in the possibility of life-threatening cardiac events. Our findings add to the literature information regarding HRV in PLMS, and highlight the need for further studies to elucidate the effects of these conditions on the ANS, and on cardiovascular health.

Comparison of Xylazine and Lidocaine Infusion versus Medetomidine Continuous Rate Infusion during General Anesthesia with Isoflurane in Horses Undergoing Emergency Laparotomy.

(1) The main goals of general anesthesia include pain management and a safe anesthetic protocol for smooth recovery. In this retrospective study, we compared two anesthetic protocols for general anesthesia with isoflurane during emergency laparotomy: sedation with xylazine and the intraoperative infusion of lidocaine (X group) versus medetomidine as a preoperative sedation and intraoperative infusion (M group). (2) The medical records of horses who underwent emergency laparotomies between 2016 and 2023 were reviewed. According to the anesthetic protocol, patients were allocated to the X or M groups. Data about the horse, signalment, history, and anesthetic variables were analyzed. (3) Group X had a significantly higher heart rate (HR), lower respiratory rate (RR) and mean and diastolic arterial pressure (MAP/DAP). A progressive increase in HR and RR was observed in both groups. Group X underwent a decrease in RR and an increase in DAP. In Group M, a decrease in MAP and DAP was observed. Group M exhibited a longer recovery time with similar recovery scores. Both protocols provided safe anesthesia for emergency laparotomy, with minor cardiovascular and respiratory depression. Minor respiratory depression was detected when xylazine was used, while recovery was longer with medetomidine.

Type 2 diabetes is linked to higher physiologic markers of effort during exercise.

People with type 2 diabetes (T2D) have lower rates of physical activity (PA) than the general population. This is significant because insufficient PA is linked to cardiovascular morbidity and mortality, particularly in individuals with T2D. Previously, we identified a novel barrier to physical activity: greater perceived effort during exercise in women. Specifically, women with T2D experienced exercise at low-intensity as greater effort than women without T2D at the same low-intensity - based on self-report and objective lactate measurements. A gap in the literature is whether T2D confers greater exercise effort in both sexes and across a range of work rates. Our overarching objective was to address these gaps regarding the influence of T2D and relative work intensity on exercise effort. We hypothesized that T2D status would confer greater effort during exercise across a range of work rates below the aerobic threshold. This cross-sectional study enrolled males and post-menopausal females aged 50-75 years. Measures of exercise effort included: 1) heart rate, 2) lactate and 3) self-report of Rating of Perceived Exertion (RPE); each assessment was during the final minute of a 5-minute bout of treadmill exercise. Treadmill exercise was performed at 3 work rates: 1.5 mph, 2.0 mph, and 2.5 mph, respectively. To determine factors influencing effort, separate linear mixed effect models assessed the influence of T2D on each outcome of exercise effort, controlling for work rate intensity relative to peak oxygen consumption (%VO2peak). Models were adjusted for any significant demographic associations between effort and age (years), sex (male/female), baseline physical activity, or average blood glucose levels. We enrolled n=19 people with T2D (47.4% female) and n=18 people (55.6% female) with no T2D. In the models adjusted for %VO2peak, T2D status was significantly associated with higher heart rate (p = 0.02) and lactate (p = 0.01), without a significant association with RPE (p = 0.58). Across a range of low-to-moderate intensity work rates in older, sedentary males and females, a diagnosis of T2D conferred higher objective markers of effort but did not affect RPE. Greater objective effort cannot be fully attributed to impaired fitness, as it persisted despite adjustment for %VO2peak. In order to promote regular exercise and reduce cardiovascular risk for people with T2D, 1) further efforts to understand the mechanistic targets that influence physiologic exercise effort should be sought, and 2) comparison of the effort and tolerability of alternative exercise training prescriptions is warranted.

Valuable Predictors for Non-measurability of Fractional Flow Reserve Derived From Coronary Computed Tomography Angiography.

Background The fractional flow reserve (FFR) derived from coronary computed tomography (CT) angiography (FFRCT) is a variable tool for coronary disease diagnosis that non-invasively provides the value of FFR. It can add physiological information tocoronary CT angiography (CCTA) and reduce unnecessary invasive coronary angiography (CAG). However, it cannot be analyzed in some cases, which is also called "non-measurability." While FFRCT has become globally widespread, the current data on non-measurability are lacking. This study aimed to determine the rate of non-measurability and identify predictors thereof in routine clinical settings to explore potential approaches to reduce the non-measurability rate. Methods and results This retrospective observational single-center studyincluded consecutive patients who underwent FFRCTanalysis in Japan. The mean age of the overall population was 71.3 ± 10.6, and an FFRCTof ≤0.8 was seen in 47.6% of patients with a measurable FFRCT. Of the 307 enrolled patients, FFRCT analysis was not feasible in 21 cases (6.8%). Heart rate (HR) at a CT scan and coronary calcium scores (CCS) were significantly higher in patients with non-measurability than those in patients whose FFRCT was appropriately analyzed (HR: 69.6±8.9 bpm vs. 61.0±11.1 bpm; p < 0.01; CCS; 931.2 (290.8, 1451.3) vs. 322.9 (100.7, 850.0); p < 0.01). Multiplelogisticregression showed that HR was an independent predictor for non-measurability (odds ratio: 1.05; 95% confidential interval: 1.02, 1.09; p < 0.01)). Based on the receiver operating characteristic curve analysis, the optimal cut-off value of HR and CCS was 63 bpm (specificity: 67.1%; sensitivity: 76.2%) and 729.2 (specificity: 71.3%; sensitivity: 66.7%). In addition, the combination of two features (HR > 63 bpm and CCS > 729.2) showed a high negative predictive value (99.3%) for FFRCT non-measurability. Conclusions In this study, the rate of FFRCTnon-measurability was 6.8%. Higher HR at a CT scan and CCS were significantly associated with non-measurability, and in cases with both HR and CCS below a specified threshold, the likelihood of ruling out non-measurability could be significantly high. Our findings suggest that reducing the HR to ideally under 63 bpm at the time of the CT scan significantly ensures feasibility. Further study on large-scale cohorts is warranted.

Measuring heart rate in captive chimpanzees without anesthesia.

Heart rate measurements can be useful for the monitoring of both physical and mental condition in humans and nonhuman animals. Yet, information about heart rates in chimpanzees, who are phylogenetically the closest species to humans, is scarce. Existing data on chimpanzee heart rates have mainly been collected from chimpanzees under anesthesia. To address this issue, we conducted electrocardiogram recordings in captive chimpanzees under normal conditions without anesthesia based on positive reinforcement training. We obtained a total of 771 recordings from 35 individuals (22 males and 13 females, 14-53years old) with no cardiac problems. The females had a higher heart rate than the male chimpanzees, and heart rate decreased as a function of age. In addition, heart rate was lower in the morning and increased during the day. Overall, the mean heart rate of adult males was 86.5 beats/min, and that of female chimpanzees 106.4 beats/min. Our data could serve as a reference point for future research and health-based monitoring of chimpanzee heart rates.

Effect Of Combination Benson Relaxation Therapy And Lavender Aromatherapy On The Decrease Blood Pressure In The Elderly With Hypertension In Working Area Of Madurejo Health Center Pangkalan Bun Province Central Borneo

Background: Hypertension is a condition where blood pressure exceeds normal limits, namely systolic blood pressure ≥ 140 mmHg and/or diastolic blood pressure ≥ 90 mmHg on repeated examinations. Hypertension, commonly known as high blood pressure, is caused by abnormalities in the blood arteries, preventing oxygen and nutrients from reaching the body's tissues. As an alternative treatment, the combination of Benson relaxation therapy and lavender aromatherapy has similarities in the mechanism of action, as seen in how the Benson relaxation technique works, namely focusing on specific words or sentences that are repeated repeatedly with a regular rhythm accompanied by an attitude of surrender to God Almighty while drawing deep breaths. While lavender aromatherapy works on both the physical and emotional levels, it can also help to lower anxiety, high blood pressure, heart rate, and stress. Lavender also stimulates the production of the hormones melatonin and serotonin. Aromatherapy can be used in a variety of methods, such as steam, inhalation, and compresses. Purpose : the aim of this study was to determine whether there is a combination effect of Benson relaxation therapy and lavender aromatherapy on reducing blood pressure in elderly hypertension at Madurejo Public Health Center in Pangkalan Bun. Methods: This type of quasi-experimental research used a one-group pre-test and post-test design with a sample of 30 respondents and purposive sampling. Blood pressure measurement using a tensimeter and an observation sheet using the Wilcoxon test. Results: The results showed that the blood pressure of hypertension sufferers pre-tested in category 1 was mild at 33.3%, moderate at 56.7%, and severe at 10.0%. The results of the level of type 2 diabetes mellitus post-test were in the good category (83.7%) and sufficient (16.3%). The Wilcoxon test results obtained a p value of 0.000. Conclusion: There is an effect of a combination of Benson relaxation therapy and lavender aromatherapy on reducing blood pressure in elderly hypertension at Madurejo Public Health Center, Pangkalan Bun, Central Kalimantan.

Combined blood pressure and heart rate trajectories are associated with prognosis in critically ill patients with acute aortic dissection: A group-based multi-trajectory analysis

BackgroundManaging systolic blood pressure (SBP), diastolic blood pressure (DBP), and heart rate (HR) is pivotal in acute aortic dissection (AAD) care. However, no prior studies have jointly analyzed the trajectories of these parameters. This research aimed to characterize their joint longitudinal trajectories and investigate the influence on AAD prognosis. MethodsWe included AAD patients from the Medical Information Mart for Intensive Care (MIMIC)-IV database. Using group-based multi-trajectory modeling (GBMTM), we identified combined trajectories of SBP, DBP, and HR within the initial 24 h of intensive care unit (ICU) admission. Cox proportional hazard regression, log-binomial regression, and logistic regression were employed to assess the association between trajectory groups and mortality outcomes. ResultsData from 337 patients were analyzed. GBMTM identified five combined trajectory groups. Group 1 featured rapidly declining SBP and DBP with high pulse pressure and low HR; Group 2 showed high to moderate SBP with slight rebound and persistently low HR; Group 3 displayed persistently moderate BP and HR; Group 4 was characterized by moderate blood pressure with persistently high HR; and Group 5 had high to moderate SBP with slight rebound, high but gradually declining DBP, and slightly high HR. Group 3 demonstrated a lower risk of mortality, with an adjusted hazard ratio of 0.32 (95 % CI, 0.14–0.74), and the adjusted relative risks for in-hospital, 30-day, and 1-year mortalities were 0.37 (95 % CI, 0.15–0.87), 0.25 (95 % CI, 0.10–0.62), and 0.41 (95 % CI, 0.22–0.79), respectively. The time-independent C-index curve demonstrated that the multi-trajectory groups had higher C-index values than any univariate trajectory groups or admission values of SBP, DBP, and HR. ConclusionsUtilization of GBMTM can yield data-driven insights to identify distinct subphenotypes in AAD patients. The combined trajectories of SBP, DBP, and HR within 24 h of ICU admission significantly influenced the mortality rate.

Therapeutic potential of conduction system pacing as a method for improving cardiac output during ventricular tachycardia.

Ventricular tachycardia (VT) reduces cardiac output through high heart rates, loss of atrioventricular synchrony, and loss of ventricular synchrony. We studied the contribution of each mechanism and explored the potential therapeutic utility of His bundle pacing to improve cardiac output during VT. Study 1 aimed to improve the understanding of mechanisms of harm during VT (using pacing simulated VT). In 23 patients with left ventricular impairment, we recorded continuous ECG and beat-by-beat blood pressure measurements. We assessed the hemodynamic impact of heart rate and restoration of atrial and biventricular synchrony. Study 2 investigated novel pacing interventions during clinical VT by evaluating the hemodynamic effects of His bundle pacing at 5bpm above the VT rate in 10 patients. In Study 1, at progressively higher rates of simulated VT, systolic blood pressure declined: at rates of 125, 160, and 190bpm, -22.2%, -42.0%, and -58.7%, respectively (ANOVA p < 0.0001). Restoring atrial synchrony alone had only a modest beneficial effect on systolic blood pressure (+ 3.6% at 160bpm, p = 0.2117), restoring biventricular synchrony alone had a greater effect (+ 9.1% at 160bpm, p = 0.242), and simultaneously restoring both significantly increased systolic blood pressure (+ 31.6% at 160bpm, p = 0.0003). In Study 2, the mean rate of clinical VT was 143 ± 21bpm. His bundle pacing increased systolic blood pressure by + 14.2% (p = 0.0023). In 6 of 10 patients, VT terminated with His bundle pacing. Restoring atrial and biventricular synchrony improved hemodynamic function in simulated and clinical VT. Conduction system pacing could improve VT tolerability and treatment.