A Novel Adaptive Noise Elimination Algorithm in Long RR Interval Sequences for Heart Rate Variability Analysis.

As heart rate variability (HRV) studies become more and more prevalent in clinical practice, one of the most common and significant causes of errors is associated with distorted RR interval (RRI) data acquisition. The nature of such artifacts can be both mechanical as well as software based. Various currently used noise elimination in RRI sequences methods use filtering algorithms that eliminate artifacts without taking into account the fact that the whole RRI sequence time cannot be shortened or lengthened.

Defining the nocturnal period in 24-h ambulatory blood pressure monitoring: a comparison of three methods.

Objectives: The purpose of our study was to compare three definitions of ambulatory blood pressure (BP) nocturnal period and to assess their agreement in determining nocturnal BP dipping patterns.

Methods: We investigated 69 subjects with metabolic syndrome, aged 50-55 years. In all subjects, we assessed 24-h BP monitoring, electrocardiogram and actigraphy profiles.

Daily Heart Rate Variability Indices in Subjects with and Without Metabolic Syndrome Before and After the Elimination of the Influence of Day-Time Physical Activity.

The available research shows conflicting data on the heart rate variability (HRV) in metabolic syndrome (MetS) subjects. The discrepancy suggests a methodical shortcoming: due to the influence of physical activity, the standard measuring of HRV at rest is not comparable with HRV assessment based on 24h Holter monitoring, which is preferred because of its comprehensiveness. To obtain a more reliable measure and to clarify to what extent HRV is altered in MetS, we assessed a 24h HRV before and after the elimination of the influence of physical activity.

Impact of a Cognitive Behavioral Intervention on Health-Related Quality of Life and General Heart Rate Variability in Patients Following Cardiac Surgery: An Effectiveness Study.

Background: Although there is evidence supporting the efficacy of cognitive-behavioral therapy (CBT) in decreasing psychologic symptoms and improving health-related quality of life in patients who have undergone coronary artery bypass graft surgery, the effectiveness of these interventions in usual health care practice, and their effect on general heart rate variability (HRV), has not been tested.

Objective: This study investigated the effectiveness of CBT in improving health-related quality of life and HRV in patients with postcardiac surgery.

Methods: However, 2 months following surgery, 150 patients were assigned sequentially to a CBT group that received the intervention for 9 months or a comparison group that received usual care.

Specific fatigue-related items in self-rating depression scales do not bias an association between depression and fatigue in patients with coronary artery disease.

Objective: Self-rating instruments for depression include questions targeting fatigue, which is a common symptom of coronary artery disease (CAD) patients. We evaluated if specific fatigue-related questions in self-reported instruments of depression bias an association between fatigue and depression in CAD patients.

Methods: A total of 1470 CAD patients attending cardiac rehabilitation program were evaluated for fatigue using the Multidimensional Fatigue Inventory (MFI-20) and for symptoms of depression using the depression subscale of the Hospital Anxiety and Depression scale (HADS-D) and the Beck Depression Inventory-II (BDI-II).

Relationship of fatigue and exercise capacity with emotional and physical state in patients with coronary artery disease admitted for rehabilitation program.

Background: The relationship between subjective fatigue, exercise capacity, and symptoms of depression and anxiety in patients with coronary artery disease (CAD) needs to be specified.

Methods: In this cross-sectional study, a total of 1,470 (64% men; mean age 57 ± 11 years) consecutive CAD patients admitted for cardiac rehabilitation after treatment of acute cardiac events were evaluated for demographic characteristics, for past and current diagnosis and treatment, for New York Heart Association (NYHA) class, for symptoms of depression and for symptoms of anxiety using the Hospital Anxiety and Depression Scale, and for subjective fatigue using the Multidimensional Fatigue Inventory. On the next day, all patients underwent exercise capacity evaluation using a standard bicycle ergometer testing procedure.

Construct and criterion validity of the DUFS and DEFS⁴ in Lithuanian patients with coronary artery disease.

Background: Fatigue has become an important symptom in clinical diagnosis and clinical trials among subjects with cardiovascular diseases and disease-specific fatigue scales were developed in a Dutch and English version.

Objective: Various questionnaires for measuring fatigue have been developed, but currently no validated questionnaire targeted at subjects with cardiovascular disease and heart failure exists in the Lithuanian language.

Methods: Despite the rigor of the exploratory factor analysis and analyses of the psychometric properties of the disease-specific Dutch Fatigue Scale and the Dutch Exertion Fatigue Scale (DUFS-DEFS) we adopted a confirmatory approach considered as the gold standard method for the evaluation of construct validity in psychometric inventories.