Background: It has been shown that heart rate variability is decreased in patients with congestive heart failure and that depressed heart rate variability is associated with a propensity to ventricular arrhythmias. Little is known, however, about heart rate variability in patients with both congestive heart failure and ventricular arrhythmias.
Methods: Spectral heart rate variability was analysed from 24 hour ambulatory electrocardiograms in 15 controls, 15 patients with non-sustained ventricular tachycardia associated with clinically normal hearts (NHVT group), and 40 patients with congestive heart failure (CHF group) secondary to either ischaemic heart disease (n = 15) or idiopathic dilated cardiomyopathy (n = 25). Of the 40 patients with congestive heart failure 15 had no appreciable ventricular arrhythmias (ventricular extrasystoles < 10 beats/h and no salvos) and formed the CHF-VA- group. Another 15 patients with congestive heart failure and non-sustained ventricular tachycardia formed the CHF-NSVT group.
Results: Heart rate variability was significantly lower in the CHF group than in controls (mean (SD) total frequency 23 (12) v 43 (13) ms; low frequency 12 (8) v 28 (9) ms; high frequency 8 (5) v 14 (7) ms; p < 0.001). The differences in heart rate variability between controls and the NHVT group, between ischaemic heart disease and dilated cardiomyopathy, and between the CHF-VA- and CHF-NSVT groups were not significant. In the CHF group heart rate variability was significantly related to left ventricular ejection fraction but not associated with ventricular arrhythmias. The frequency of ventricular extrasystoles was significantly related to the high frequency component of heart rate variability (r = 0.54, p < 0.05) in the NHVT group. Stepwise multiple regression analysis showed that in the CHF group, heart rate variability was predominantly related to left ventricular ejection fraction (p < 0.05). There was no significant difference in heart rate variability between survivors (n = 34) and those who died suddenly (n = 6) at one year of follow up in the CHF group.
Conclusion: In patients with congestive heart failure, heart rate variability is significantly decreased. The depressed heart rate variability is principally related to the degree of left ventricular impairment and is independent of aetiology and the presence of ventricular arrhythmias. The data suggest that analysis of heart rate variability does not help the identification of patients with congestive heart failure at increased risk of sudden death.
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http://dx.doi.org/10.1136/hrt.71.4.322 | DOI Listing |
Sleep
January 2025
Sleep Research & Treatment Center, Department of Psychiatry & Behavioral Health, Penn State University, College of Medicine, Hershey PA, USA.
Study Objectives: Although heart rate variability (HRV), a marker of cardiac autonomic modulation (CAM), is known to predict cardiovascular morbidity, the circadian timing of sleep (CTS) is also involved in autonomic modulation. We examined whether circadian misalignment is associated with blunted HRV in adolescents as a function of entrainment to school or on-breaks.
Methods: We evaluated 360 subjects from the Penn State Child Cohort (median 16y) who had at least 3-night at-home actigraphy (ACT), in-lab 9-h polysomnography (PSG) and 24-h Holter-monitoring heart rate variability (HRV) data.
Ultrasound Obstet Gynecol
January 2025
Department of Obstetrics and Gynaecology, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, SAR, China.
Objectives: To compare the maternal hemodynamic profile at 12 + 0 to 15 + 6 weeks' gestation in women who subsequently developed pre-eclampsia (PE) and those who did not, and to assess the screening performance of maternal hemodynamic parameters for PE in combination with the Fetal Medicine Foundation (FMF) triple test, including maternal factors (MF), mean arterial pressure (MAP), uterine artery pulsatility index and placental growth factor.
Methods: This was a prospective case-control study involving Chinese women with a singleton pregnancy who underwent preterm PE screening at 11 + 0 to 13 + 6 weeks' gestation using the FMF triple test, between February 2020 and February 2023. Women identified as being at high risk (≥ 1:100) for preterm PE by the FMF triple test were matched 1:1 with women identified as low risk (< 1:100) for maternal age ± 3 years, maternal weight ± 5 kg and date of screening ± 14 days.
Zhongguo Dang Dai Er Ke Za Zhi
January 2025
Department of Cardiovascular Medicine, Children's Hospital of Chongqing Medical University/National Clinical Medical Research Centre for Children's Health and Diseases/National International Science and Technology Cooperation Base for Major Diseases of Children's Development/Key Laboratory of Children's Vital Organ Development and Diseases of Chongqing Municipal Health Commission/National Key Clinical Cardiovascular Specialty, Chongqing 400014, China.
Heart failure is a complex clinical syndrome and pediatric heart failure (PHF) has a high mortality rate. Early diagnosis is crucial for treatment and management of PHF. In clinical practice, various tests and examinations play a key role in the diagnosis of PHF, including continuously updated biomarkers, echocardiography, and cardiac magnetic resonance imaging.
View Article and Find Full Text PDFCrit Care
January 2025
Department of Intensive Care Unit, The First Affiliated Hospital of Jinan University, Guangzhou, China.
Background: Despite the physiological advantages of positive end-expiratory pressure (PEEP), its optimal utilization during one-lung ventilation (OLV) remains uncertain. We aimed to investigate whether individualized PEEP titration by lung compliance is associated with a reduced risk of postoperative pulmonary complications during OLV.
Methods: We searched PubMed, Embase, and the Cochrane Central Register of Controlled Trials until April 1, 2024, to identify published randomized controlled trials that compared individualized PEEP titration by lung compliance with fixed PEEP during OLV.
Thromb J
January 2025
Pediatric Emergency Department, St. Christopher's Hopsoital for Children, Philadelphia, PA, USA.
Background: Acute pulmonary embolism (PE) is a serious and potentially fatal condition that is relatively rare in the pediatric population. In patients presenting with massive/submassive PE, catheter-directed Therapy (CDT) presents an emerging therapeutic modality by which PE can be managed.
Methods: Electronic databases were systematically searched through May 2024.
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