Nighttime Heart Rate Research Articles

Deriving Accurate Nocturnal Heart Rate, rMSSD and Frequency HRV from the Oura Ring

Cardiovascular diseases are a major cause of mortality worldwide. Long-term monitoring of nighttime heart rate (HR) and heart rate variability (HRV) may be useful in identifying latent cardiovascular risk. The Oura Ring has shown excellent correlation only with ECG-derived HR, but not HRV. We thus assessed if stringent data quality filters can improve the accuracy of time-domain and frequency-domain HRV measures. 92 younger (<45 years) and 22 older (≥45 years) participants from two in-lab sleep studies with concurrent overnight Oura and ECG data acquisition were analyzed. For each 5 min segment during time-in-bed, the validity proportion (percentage of interbeat intervals rated as valid) was calculated. We evaluated the accuracy of Oura-derived HR and HRV measures against ECG at different validity proportion thresholds: 80%, 50%, and 30%; and aggregated over different durations: 5 min, 30 min, and Night-level. Strong correlation and agreements were obtained for both age groups across all HR and HRV metrics and window sizes. More stringent validity proportion thresholds and averaging over longer time windows (i.e., 30 min and night) improved accuracy. Higher discrepancies were found for HRV measures, with more than half of older participants exceeding 10% Median Absolute Percentage Error. Accurate HRV measures can be obtained from Oura’s PPG-derived signals with a stringent validity proportion threshold of around 80% for each 5 min segment and aggregating over time windows of at least 30 min.

Circadian heart rate fluctuations predict 21-year cardiovascular and all-cause mortality in type 2 and type 1 diabetes

Abstract Background Alterations in circadian heart rate (HR) fluctuations have been associated with cardiovascular events in the general population. This study aimed at defining their long-term prognostic value for cardiovascular and all-cause mortality in patients with diabetes. Methods We examined a cohort of 349 patients with type 2 or type 1 diabetes (52% women, age 57.1±11.9 years, BMI 29.4±5.9 kg/m2, HbA1c 8.6±2.1%, 81% type 2 diabetes) who underwent 24h ambulatory blood pressure and HR monitoring (ABPM) and assessment of diabetic microvascular complications. The median standard deviation (SD) value of ABPM-derived HR measurements was used to define patients with low daily HR fluctuations (low 24h-HR SD), while a <10% decline in average night-time vs day-time HR identified patients with blunted nocturnal HR dip (n=107, 31%). The clinical features and time-dependent prognostic impact of these conditions were evaluated over a 21-year observational follow-up. Results Low 24h-HR SD and blunted nocturnal HR dip were associated with an adverse cardiometabolic risk profile and high prevalence of cardiac autonomic neuropathy and nephropathy. After 6,251 person-years of follow-up (21.0 [14.0-21.0] years), a total of 136 (39%) deaths occurred, of which 100 (68%) of cardiovascular cause. After adjustment for potential confounders, the low 24h-HR SD group had a higher risk for both cardiovascular (hazard ratio 1.99, 95% CI 1.29–3.06, p=0.002) and all-cause mortality (hazard ratio 1.50, 95% CI 1.03–2.18, p=0.033), compared with high 24h-HR SD. Consistently, patients with blunted nocturnal HR dip had a higher adjusted risk for cardiovascular (1.61, 95% CI 1.07–2.43, p=0.023) and all-cause mortality (1.61, 95% CI 1.11–2.34, p=0.012), compared with those with preserved nocturnal HR dip. Conclusions Impaired circadian HR fluctuations are frequent in patients with long-standing diabetes and are associated with microvascular disease and increased long-term cardiovascular and all-cause mortality. Identifying these conditions via 24h-ABPM may provide a cost-effective risk stratification tool in this high-risk population.Kaplan-Meier curves

Continuous heart monitoring to evaluate treatment effects in pulmonary hypertension

Abstract Background The treatment of pulmonary hypertension (PH) has improved rapidly in recent years, and there is increasing evidence to support the role of early intervention. However, studies demonstrate that timely intervention is often still lagging which affects clinical outcomes in patients with PH. Purpose To assess treatment effects after escalation of specific PH treatments using continuous heart monitoring via a Reveal LINQ loop recorder. Methods The patients change in heart rate variability (HRV), heart rate (HR), and physical activity were assessed before and after treatment escalation. Treatment escalation was defined as an additional PAH drug, pulmonary endarterectomy (PEA), percutaneous balloon angioplasty (PBA), or bilateral lung transplantation (BLTX). Results In this prospective study, 41 patients (27 with PAH and 14 with chronic thromboembolic pulmonary hypertension) were enrolled. Among them, 15 patients (36.6%) underwent PH treatment escalation. Prior to escalation, patients were monitored for a median of 100 (range: 68–100) days and after therapy escalation for a median duration of 165 (range: 89–308) days. In the escalation group, a significant increase in HRV (Figure), physical activity indexed by daytime HR was observed, while a significant decrease was seen in nighttime HR assessed at baseline and after treatment escalation. These changes were found both in the PAH and CTEPH group. In parallel a significant improvement in WHO functional class, 6-minute walking distance, and N-terminal pro-b-type natriuretic peptide (NT-proBNP) was observed. Conclusions This is the first study to demonstrate a direct association between specific PH therapies and changes in HRV, HR nighttime and physical activity in patients with PAH and CTEPH. Continuous monitoring allows for an early intervention with supplementary treatment for PH. This is especially relevant considering the increasing availability of wearables that allow for a convenient measurement of relevant prognostic parameters in PH.

Different implications of daytime and nighttime heart rate variability on total burden of cerebral small vascular disease in patients with nondisabling ischemic cerebrovascular events.

This study aimed to explore the relationship between total burden of cerebral small vessel disease (CSVD) and daytime and nighttime heart rate variability (HRV) parameters. Consecutive patients with nondisabling ischemic cerebrovascular events were recruited from the cerebrovascular disease clinic of Changzhou Second People's Hospital between January 2022 and June 2023. A total of 144 enrolled participants were divided into a mild CSVD group (74 patients) and a moderate-to-severe CSVD group (70 patients) based on total burden of CSVD. Various HRV parameters measured during 24-h, 4-h daytime, and 4-h nighttime periods (including natural log-transformed [ln] root mean square of successive RR interval differences [RMSSD], ln absolute power of the high-frequency band [0.15-0.4 Hz] [HF], ln absolute power of the low-frequency band [0.04-0.15 Hz][LF], and LF-to-HF ratio [LF/HF]) were then assessed in the 2 groups. Spearman correlation analysis was used to assess the correlation between total burden of CSVD and HRV parameters. HRV parameters with P-value < 0.05 in correlation analysis were included in the multivariable logistic regression analysis, and restricted cubic spline analysis was performed to assess dose-response relationships. Daytime 4-h lnRMSSD (r = -0.221; P = 0.008) and 4-h lnHF (r = -0.232; P = 0.005) were negatively correlated with total burden of CSVD, and daytime 4-h lnLF/HF (r = 0.187; P = 0.025) was positively correlated with total burden of CSVD. There was no correlation between nighttime HRV parameters and total burden of CSVD. After adjustments were made for potential confounders, daytime 4-h lnRMSSD (OR = 0.34; 95% CI: 0.16-0.76), 4-h lnHF (OR = 0.57; 95% CI: 0.39-0.84), and 4-h lnLF/HF (OR = 2.12; 95% CI: 1.18-3.82) were independent predictors of total burden of CSVD (all P < 0.05). S-shaped linear associations with moderate-to-severe total burden of CSVD were seen for daytime 4h-lnRMSSD (P for nonlinearity = 0.543), 4-h lnHF (P for nonlinearity = 0.31), and 4-h lnLF/HF (P for nonlinearity = 0.502). Daytime parasympathetic HRV parameters are independent influencing factors of total burden of CSVD and may serve as potential therapeutic observation indicators for CSVD.

Long-Term Differences in AutonomicAlterations After Cryoballoonvs Radiofrequency AtrialFibrillation Ablation.

The long-term natural history of autonomic alterations following catheter ablation of drug-refractory paroxysmal atrial fibrillation is poorly defined. The authors sought to define the long-term impact of thermal catheter ablation on the cardiac autonomic system. The study included 346 patients with drug-refractory paroxysmal atrial fibrillation undergoing pulmonary vein isolation using thermal ablation energy (radiofrequency or cryoballoon ablation). All patients underwent insertion of a Reveal LINQ implantable cardiac monitor prior to ablation. The implantable cardiac monitor continuously recorded physical activity, heart rate variability (HRV) (measured as the standard deviation of the average normal-to-normal), daytime heart rate, and nighttime heart rate (NHR). Longitudinal autonomic data in the 2-month period prior to the date of ablation were compared with the 3 years following ablation. Following ablation, there was a significant decrease in HRV (10-20ms; P< 0.0001) and significant increases in daytime heart rate and NHR (10 beats/min [P< 0.0001] and 7 beats/min [P< 0.0001], respectively). Changes in autonomic parameters were greatest in the first 3months following ablation but remained significantly different from baseline for 36months following ablation. Greater changes in NHR and HRV were associated with improved freedom from recurrent arrhythmia. The type of thermal ablation energy had no influence on the heart rate and autonomic parameters. Pulmonary vein isolation using thermal ablation energy results in significant sustained changes in the heart rate parameters related to autonomic function. These changes are independent of the ablation technology employed and are associated with procedural success. (Cryoballoon vs Irrigated Radiofrequency Catheter Ablation: Double Short vs Standard Exposure Duration [CIRCA-DOSE]; NCT01913522).

Continuous Monitoring of Heart Rate Variability and Respiration for the Remote Diagnosis of Chronic Obstructive Pulmonary Disease: Prospective Observational Study.

Conventional daytime monitoring in a single day may be influenced by factors such as motion artifacts and emotions, and continuous monitoring of nighttime heart rate variability (HRV) and respiration to assist in chronic obstructive pulmonary disease (COPD) diagnosis has not been reported yet. The aim of this study was to explore and compare the effects of continuously monitored HRV, heart rate (HR), and respiration during night sleep on the remote diagnosis of COPD. We recruited patients with different severities of COPD and healthy controls between January 2021 and November 2022. Vital signs such as HRV, HR, and respiration were recorded using noncontact bed sensors from 10 PM to 8 AM of the following day, and the recordings of each patient lasted for at least 30 days. We obtained statistical means of HRV, HR, and respiration over time periods of 7, 14, and 30 days by continuous monitoring. Additionally, the effects that the statistical means of HRV, HR, and respiration had on COPD diagnosis were evaluated at different times of recordings. In this study, 146 individuals were enrolled: 37 patients with COPD in the case group and 109 participants in the control group. The median number of continuous night-sleep monitoring days per person was 56.5 (IQR 32.0-113.0) days. Using the features regarding the statistical means of HRV, HR, and respiration over 1, 7, 14, and 30 days, binary logistic regression classification of COPD yielded an accuracy, Youden index, and area under the receiver operating characteristic curve of 0.958, 0.904, and 0.989, respectively. The classification performance for COPD diagnosis was directionally proportional to the monitoring duration of vital signs at night. The importance of the features for diagnosis was determined by the statistical means of respiration, HRV, and HR, which followed the order of respiration > HRV > HR. Specifically, the statistical means of the duration of respiration rate faster than 21 times/min (RRF), high frequency band power of 0.15-0.40 Hz (HF), and respiration rate (RR) were identified as the top 3 most significant features for classification, corresponding to cutoff values of 0.1 minute, 1316.3 nU, and 16.3 times/min, respectively. Continuous monitoring of nocturnal vital signs has significant potential for the remote diagnosis of COPD. As the duration of night-sleep monitoring increased from 1 to 30 days, the statistical means of HRV, HR, and respiration showed a better reflection of an individual's health condition compared to monitoring the vital signs in a single day or night, and better was the classification performance for COPD diagnosis. Further, the statistical means of RRF, HF, and RR are crucial features for diagnosing COPD, demonstrating the importance of monitoring HRV and respiration during night sleep.

The search for optimal nocturnal diurnal heart rate Index targets in ICU patients: a retrospective observational study from large ICU database.

Circadian rhythms play a crucial role in cardiovascular health, with the nocturnal diurnal heart rate index (NDHRI) reflecting significant circadian variations. However, the optimal NDHRI target in Intensive Care Unit (ICU) patients remains undefined. This study aims to establish an evidence-based NDHRI target range and assess its association with mortality. Data from the eICU Collaborative Research Database (n = 32,412) were analyzed. NDHRI was calculated by dividing cumulative nighttime heart rate area by daytime area. Generalized additive models (GAMs) explored the non-linear relationship between mean NDHRI and mortality, adjusting for confounders. Subgroup analyses were conducted based on ethnicity, ICU type, and comorbidities. A U-shaped association was observed between hospital mortality and mean NDHRI (P < 0.001). The optimal NDHRI range (40.0%-45.0%) demonstrated the lowest mortality rates. The duration spent within this range correlated inversely with mortality (P < 0.001). Subgroup analyses consistently supported these findings across diverse patient profiles. Our findings suggest an association between maintaining NDHRI within the 40.0%-45.0% range and lower mortality rates in critically ill patients, highlighting the potential utility of monitoring circadian heart rate variations in the ICU. Further research and future randomized controlled trials are essential to confirm causality and should consider this NDHRI range as a pivotal reference target.

Reference ranges for ambulatory heart rate measurements in a middle-aged population

BackgroundElevated heart rate (HR) predicts cardiovascular disease and mortality, but there are no established normal limits for ambulatory HR. We used data from the Swedish CArdioPulmonary Imaging Study to determine...

BLOOD PRESSURE SURGE DURING THE EARTHQUAKE IN CITY OF PETRINJA, BANIJA REGION IN CROATIA

Objective: Stress is known to contribute to other well-known environmental risk factors to hypertension leading to sympathetic overactivity. While usual environmental factors can be easily measured, exposure to stress is difficult to objectivize, especially during catastrophic events which are recognized as main stressors. There are several reports about earthquakes, blood pressure (BP) and cardiovascular events. Design and method: We are reporting a case on ambulatory blood pressure monitoring (ABPM) in 42-year-old women during Croatian earthquake. Results: A 42-year-old women with multiple genetic and environmental risk factors for hypertension was evaluated for secondary hypertension, and adult autosomal polycystic kidney disease was diagnosed. Kidney function was normal and there were no signs of target organ damage. She was treated with a fixed dose combination perindopril/amlodipine 4/5 mg (morning). ABPM revealed mildly uncontrolled systolic-diastolic hypertension with extreme nocturnal dip. Average 24-hour, daytime and nighttime BP values were 130±20,4/79±19,9 mmHg, 137±16,2 /85±17,9 mmHg, 100±11,8 /55±11,7 mmHg, respectively. White coat effect was present, and masked hypertension was ruled out. Average 24-hour, daytime and nighttime heart rate were: 88b/min, 93b/min, and 79b/min. A significant surge in BP and heart rate (200/130 mmHg,140 b/min) was recorded at 12:30 p.m. exactly at the time when earthquake occurred in city Petrinja, also felt in Zagreb city. The earthquake was clearly stated in the blood pressure diary (Figure 1). Conclusions: Although chronic stress is emphasized to affect human health more than acute, catastrophic events such as earthquakes can have deleterious effect such as enormous elevation of BP. It is necessary to have strategies for BP management in disaster-related diseases to prevent organ damage.

Continuous heart monitoring to evaluate treatment effects in pulmonary hypertension

BackgroundThe treatment of pulmonary hypertension (PH) has improved rapidly in recent decades. There is increasing evidence to support the role of early intervention and treatment in affecting clinical outcomes in...

Ambulatory Risk Stratification for Worsening Heart Failure in Patients with Reduced and Preserved Ejection Fraction Using Diagnostic Parameters Available in Implantable Cardiac Monitors.

Ambulatory risk stratification for worsening heart failure (HF) using diagnostics measured by insertable cardiac monitors (ICM) may depend on the left ventricular ejection fraction (LVEF). We evaluated risk stratification performance in patients with reduced versus preserved LVEF. ICM patients with a history of HF events (HFEs) were included from the Optum® de-identified Electronic Health Record dataset merged with ICM device-collected data during 2007-2021. ICM measures nighttime heart rate (NHR), heart rate variability (HRV), atrial fibrillation (AF) burden, rate during AF, and activity duration (ACT) daily. Each diagnostic was categorized into high, medium, or low risk using previously defined features. HFEs were HF-related inpatient, observation unit, or emergency department stays with IV diuresis administration. Patients were divided into two cohorts: LVEF ≤ 40% and LVEF > 40%. A marginal Cox proportional hazards model compared HFEs for different risk groups. A total of 1020 ICM patients with 18,383 follow-up months and 301 months with HFEs (1.6%) were included. Monthly evaluations with a high risk were 2.3, 4.2, 5.0, and 4.5 times (p < 0.001 for all) more likely to have HFEs in the next 30 days compared to those with a low risk for AF, ACT, NHR, and HRV, respectively. HFE rates were higher for patients with LVEF > 40% compared to LVEF ≤ 40% (2.0% vs. 1.3%), and the relative risk between high-risk and low-risk for each diagnostic parameter was higher for patients with LVEF ≤ 40%. Diagnostics measured by ICM identified patients at risk for impending HFEs. Patients with preserved LVEF showed a higher absolute risk, and the relative risk between risk groups was higher in patients with reduced LVEF.

Night time heart rate predicts next-day pain in fibromyalgia and primary back pain.

Primary chronic pain is pain that persists for over 3 months without associated measurable tissue damage. One of the most consistent findings in primary chronic pain is its association with autonomic hyperactivation. Yet whether the autonomic hyperactivation causes the pain or results from it is still unclear. It is also unclear to what extent autonomic hyperactivation is related to experienced pain intensity in different subtypes or primary chronic pain. Our first aim was to test lagged relationships between the markers of autonomic activation (heart rate) and pain intensity to determine its directionality. The main question here was whether autonomic biomarkers predict pain intensity or whether pain intensity predicts autonomic biomarkers. The second aim was to test whether this relationship is different between people with primary back pain and people with fibromyalgia. Sixty-six patients with chronic pain were observed over an average of 81 days. Sleep heart rate and heart rate variability were measured with a wearable sensor, and pain intensity was assessed from daily subjective reports. The results showed a predictive relationship between sleep heart rate and next-day pain intensity (P < 0.05), but not between daily pain intensity and next night heart rate. There was no interaction with the type of chronic pain. These findings suggest that autonomic hyperactivation, whether stress-driven or arising from other causes, precedes increases in primary chronic pain. Moreover, the present results suggest that autonomic hyperactivation is a common mechanism underlying the pain experience in fibromyalgia and chronic back pain.

Heart Rate and Heart Rate Variability in Healthy Preterm-Born Young Adults and Association with Vitamin D: A Wearable Device Assessment.

Prematurity has been associated with impaired parasympathetic cardiac regulation later in life. Changes in heart rate (HR) and heart rate variability (HRV) may indicate a risk for future cardiac dysfunction. The putative role of Vitamin D on cardiac autonomic function in individuals born preterm (PT) remains unknown. This study involves monitoring autonomic cardiac regulation and Vitamin D concentrations in 30 PT and 16 full-term (FT) young adults in a free-living context. The PT subjects were born between 1994 and 1997 at Oulu University Hospital. The inclusion criteria were (1) being born ≤ 32 gestation weeks or (2) being born < 34 gestation weeks with a birth weight under 1500 g. Participants wore an Oura ring sleep tracer, a smart ring device, for 2 weeks to monitor cardiac autonomic function. Parameters related to autonomic cardiac regulation, lowest nighttime resting HR, and the root mean square of successive differences (RMSSD) to describe HRV were collected. PT males exhibited a tendency toward lower RMSSD (71.8 ± 22.6) compared to FT males (95.63 ± 29.0; p = 0.10). Female participants had a similar mean RMSSD in the FT and PT groups at 72.04 ± 33.2 and 74.0 ± 35.0, respectively. Serum 25-hydroxyvitamin D concentration did not correlate with cardiac autonomic function parameters. When assessing the lowest resting nighttime HRs and HRVs in a long-term, real-world context, healthy female PT young adults performed similarly to their FT peers. In contrast, the present study's results suggest that male PT young adults exhibit impaired autonomic cardiac function, potentially putting them at risk for cardiovascular disease later in adulthood.

Differences in risk stratification for worsening heart failure in patient with reduced versus preserved ejection fraction using diagnostic parameters available in implantable cardiac monitors

Abstract Background Ambulatory management of heart failure (HF) patients require the ability to identify when patients are at highest risk of impending HF events (HFE). The risk stratification ability based on diagnostic parameters measured by implantable cardiac monitors may differ depending on the left ventricular ejection fraction (LVEF) of HF patients. Objective The purpose of this study was to evaluate the difference in risk stratification performance of individual diagnostic parameters currently available in ICMs in identifying patients at increasing risk of HFE in patients with reduced versus preserved LVEF. Methods Patients with history of HFE who were implanted with an ICM was identified from the aggregated and de-identified electronic health record (EHR) database during 2007-2021. The device collected data were merged with the EHR data to create a de-identified database of real-world patients. Currently approved ICMs measure nighttime heart rate (NHR), heart rate variability (HRV), atrial fibrillation (AF) burden, ventricular rate during AF, and activity duration (ACT) daily and stores and transmits this information for the lifetime of the device. Each diagnostic parameter was categorized into high, medium, or low risk using a combination of features predefined in earlier studies. HFEs were defined as inpatient stay with a primary diagnosis of HF or HF related observation unit or emergency visit with IV diuresis administration. Patients were divided into two cohorts of patients with (1) median LVEF ≤ 40% (HFrEF), and (2) median LVEF &amp;gt; 40% (HFpEF). Performance evaluation was performed by simulating monthly follow-ups which consisted of looking at the individual parameter risk states in the last 30 days and evaluating the occurrence of HF events in the following 30 days. A marginal Cox proportional hazards model was used to compare HF events for different risk groups (high, medium, and low) for each individual diagnostic parameter. Results There was a total of 267 patients with median LVEF ≤ 40% (64±13 years old, 67% male) and 622 patients with LVEF&amp;gt;40% (69 ±12 years old, 47% male). For the reduced LVEF cohort, there was a total of 4,867 follow-up months with 65 monthly evaluations (1.3%) had an HF event in the next 30 days. For the preserved LVEF cohort, there was a total of 11,057 follow-up months with 224 monthly evaluations (2.0%) had an HF event in the next 30 days. The event rate comparisons between the risk groups for each individual diagnostic parameter are shown in Figure. As compared to ICM patients with HFrEF, ICM patients with HFpEF had higher absolute event rate across all risk groups, thus lowering the relative risk stratification between risk groups. Conclusion ICM patients with HFpEF showed a higher event rate and hence a higher absolute risk for each risk group, however relative risk between risk groups and hence the risk stratification performance for identifying risk for worsening HF was better in patients with HFrEF.

Skin sodium content as a predictor of blood pressure response to renal denervation

Patients with treatment resistant hypertension (TRH) are known to have elevated sodium (Na) content in muscle and skin. Renal denervation (RDN) emerged as an adjacent therapeutic option in this group of patients. This analysis aimed at evaluating whether tissue Na content predicts blood pressure (BP) response after RDN in patients with TRH. Radiofrequency-device based RDN was performed in 58 patients with uncontrolled TRH. Office and 24-h ambulatory BP were measured at baseline and after 6 months. To assess tissue Na content Na magnetic resonance imaging (Na-MRI) was performed at baseline prior to RDN. We splitted the study cohort into responders and non-responders based on the median of systolic 24-h ambulatory blood pressure (ABP) reduction after 6 months and evaluated the association between BP response to RDN and tissue Na content in skin and muscle. The study was registered at http://www.clinicaltrials.gov (NCT01687725). Six months after RDN 24-h ABP decreased by −8.6/−4.7 mmHg. BP-Responders were characterized by the following parameters: low tissue sodium content in the skin (p = 0.040), female gender (p = 0.027), intake of aldosterone antagonists (p = 0.032), high baseline 24-h night-time heart rate (p = 0.045) and high LDL cholesterol (p < 0.001). These results remained significant after adjustment for baseline 24-h systolic BP. Similar results were obtained when the median of day-time and night-time ABP reduction after 6 months were used as cut-off criteria for defining BP response to RDN. We conclude that in addition to clinical factors including baseline 24-h ABP Na-MRI may assist to select patients with uncontrolled TRH for RDN treatment.

Immediate and Intermediate-Term Effects of Disease Mitigation Measures on Activity Levels as Measured by Implantable Cardiac Devices.

Routine activities of daily living are known to effect overall wellbeing, cardiovascular health, and quality of life. A decrease in daily activity level is recognized as a contributing factor to increasing rates of obesity and a decline in overall health. This study sought to evaluate the effect of disease mitigation strategies on activity level by evaluating changes in recorded cardiac parameters as measured by implantable cardiac devices for a period of time prior to and following implementation of COVID-19 mitigation efforts in Arizona. A retrospective cohort study of cardiac device data from January 1, 2019-December 31, 2020 was performed. Linear mixed-effects models with restricted maximum likelihood estimation were utilized to test for the fixed effects of Year, day, and the interaction between them. A significant decrease in daily activity minutes, daytime heart rates, and heart rate variability coincident with the initiation of disease mitigation strategies was observed. An increase in nighttime heart rates also coincided with initiation of disease mitigation strategies. These effects were noted to persist through the end of the study period. Implementation of statewide disease mitigation strategies resulted in both immediate and intermediate-term effects on activity levels, day and nighttime heart rates trends, and heart rate variability in patients with implanted cardiac devices. These data may serve useful in counseling patients regarding the importance of activity, movement, and exercise to routine health and encourage a return to pre-pandemic levels of activity.

Association between nighttime heart rate and cardiovascular mortality in patients with implantable cardioverter-defibrillator: A cohort study

Although studies have shown that an increased resting heart rate measured randomly at a single point of the day has been associated with adverse cardiovascular outcomes, the utility of continuous monitoring of nighttime heart rate (NTHR) has remained largely uninvestigated. This study aimed to explore the association between NTHR and cardiovascular mortality. The Study of Home Monitoring System Safety and Efficacy in Cardiac Implantable Electronic Device-implanted Patients, which is a prospective cohort study, enrolled patients with implantable cardioverter-defibrillator (ICD) or cardiac resynchronization therapy defibrillator between 2010 and 2015. Baseline NTHR was measured during the programmed sleep period from 30 to 60 days after implantation. The primary outcome was cardiovascular mortality, fitted by a restricted cubic spline function. A total of 534 implantable cardioverter-defibrillator recipients with sinus rhythm during the detection window were included in the study. The mean baseline NTHR was 59.6 ± 8.0 beats/min. During the follow-up period of 60.4 ± 21.8 months, 88 (16.5%) patients experienced cardiovascular mortality. After considering potential confounders, a linear association was observed. Each 1 beat/min increase in NTHR was associated with a 7.8%, 10.1%, and 5.7% increase in the risk of cardiovascular mortality in the total population, patients with heart failure, and patients without heart failure, respectively. Continuous monitoring of NTHR may identify patients at high risk of cardiovascular mortality in a timely manner, with the potential for "preemptive" action. No. ChiCTR-ONRC-13003695.

Continuous long-term heart rate variability and risk assessment in pulmonary hypertension

ObjectiveCurrent multimodal risk assessment for pulmonary hypertension (PH) has been redefined with a simplified assessment for follow-up in the new European Society of Cardiology/European Respiratory Society (ESC/ERS) guidelines. Follow-up risk...

IMPACT OF CELIPROLOL THERAPY ON BLOOD PRESSURE AND HEART RATE IN PATIENTS WITH VASCULAR EHLERS-DANLOS SYNDROME

Objective: Vascular Ehlers-Danlos syndrome (vEDS) is an inherited connective tissue disorder characterized by arterial fragility. Celiprolol is a beta1-adrenoceptor antagonist with partial beta2 agonist activity that has been shown to reduce rates of vascular events in this setting, though the underlying mechanisms are not yet fully understood. Aim of the present study was to assess the impact of Celiprolol on blood pressure (BP) and heart rate (HR) in patients with vEDS. Design and method: Patients with genetically confirmed disease referred to our Institution between 2011 and 2022 were divided into two groups according to whether or not they were on Celiprolol therapy. The former were included if on Celiprolol at the dose of 400 mg daily for at least 12 months. Each participant underwent office blood pressure (BP) measurement, 24-h ambulatory BP monitoring (ABPM), and pulse wave analysis (PWA) of the radial artery with calculation of central pulse pressure (PP) and augmentation index (AIx). Results: Overall, 18 patients (11 females) were included. Mean age was 36 years and mean body mass index (BMI) was 22.1 kg/m2. Eleven patients were on Celiprolol therapy. No significant differences were found between groups in terms of age, sex, BMI, and presence of hypertension (p&gt;0.05). Patients on Celiprolol therapy displayed higher values of systolic BP (SBP) (124 vs 113 mmHg; p = 0.128), diastolic BP (DBP) (76 vs 67 mmHg; p = 0.236), mean BP (92 vs 83 mmHg; p = 0.173), and HR at office BP measurement, as well as lower AIx (126 vs 140%; p = 0.176) at PWA, although the difference was not statistically significant. Similarly, no significant difference was found for all ABPM parameters (24-h, day-time, and night-time SBP, DBP, mean BP, and HR), as well as central SBP, central DBP, central mean BP, and PP at PWA between groups (p&gt;0.05). Conclusions: Our study suggests little impact of Celiprolol therapy on both BP and HR in patients with vEDS, which hints additional mechanisms behind its protective effect in this clinical setting. Further studies on larger cohorts are needed to clarify these aspects.

SKIN SODIUM CONTENT AS A PREDICTOR OF BLOOD PRESSURE RESPONSE TO RENAL DENERVATION

Objective: In patients with treatment resistant hypertension (TRH), renal denervation (RDN) emerged as an adjacent therapeutic option. It has been detected that patients with TRH have elevated Sodium (Na) content in muscle and skin. This analysis aimed at evaluating whether tissue Na content predicts blood pressure (BP) response after RDN. Design and method: Radiofrequency device based endovascular RDN was performed in 53 patients with uncontrolled TRH (office BP&gt; = 140/90 mmHg and diagnosis confirmed by 24-h ambulatory BP monitoring) in our certified RDN center. Office and 24-h ambuatory BP were measured at baseline and after 6 months. To assess tissue Na content 23Na-MRI was performed at baseline prior to RDN. We splitted the study cohort based on the median systolic 24-h ambulatory BP reduction after 6 months into responders and non-responders and compared tissue Na content and baseline characteristics between these groups. The study was registered at http://www.clinicaltrials.gov (NCT01687725). Results: 53 patients were followed up for at least 6 months. Office systolic and diastolic BP were reduced by -12.9±21.1 mmHg and -7.7±12.5 mmHg and 24-h ambulatory systolic and diastolic BP were reduced by -8.6±14.0 mmHg and -4.7±9.5 mmHg after 6 months. Responder could be characterized as patients with low tissue sodium content in skin, more female patients, patients with aldosteron-antagonists, high baseline 24-h night-time heart rate and high LDL-cholesterol (see table, only p&lt;0.10 are shown). This results remained significant after adjustment for baseline 24-h SBP. Similar results were obtained if the two groups were created based on the median of 24-h day-time and night-time BP reduction after 6 months. Conclusions: We identified Na in skin, sex, 24-h night-time heart rate, aldosterone antagonists and LDL-cholesterol as predictors of the systolic BP response. We conclude that 23Na-MRI may assist to select patients with uncontrolled TRH who will have a clinically meaningful BP reduction following RDN treatment.