Sudden changes in heart rate variability during the 1999 Taiwan earthquake

Physical Activity, Heart Rate Variability, and Ventricular Arrhythmia During the COVID-19 Lockdown: Retrospective Cohort Study

BACKGROUND

Ventricular arrhythmias (VAs) increase with stress and national disasters. Prior research has reported that VA did not increase during the onset of the COVID-19 lockdown in March 2020, and the mechanism for this is unknown.

OBJECTIVE

This study aimed to report the presence of VA and changes in 2 factors associated with VA (physical activity and heart rate variability [HRV]) at the onset of COVID-19 lockdown measures in Ontario, Canada.

METHODS

Patients with implantable cardioverter defibrillator (ICD) followed at a regional cardiac center in Ontario, Canada with data available for both HRV and physical activity between March 1 and 31, 2020, were included. HRV, physical activity, and the presence of VA were determined during the pre- (March 1-10, 2020) and immediate postlockdown (March 11-31) period. When available, these data were determined for the same period in 2019.

RESULTS

In total, 68 patients had complete data for 2020, and 40 patients had complete data for 2019. Three (7.5%) patients had VA in March 2019, whereas none had VA in March 2020 (P=.048). Physical activity was reduced during the postlockdown period (mean 2.3, SD 1.6 hours vs mean 2.1, SD 1.6 hours; P=.003). HRV was unchanged during the pre- and postlockdown period (mean 91, SD 30 ms vs mean 92, SD 28 ms; P=.84).

CONCLUSIONS

VA was infrequent during the COVID-19 pandemic. A reduction in physical activity with lockdown maneuvers may explain this observation.

Atrial Fibrillation and Stress: A 2-Way Street?

The accumulating literature linking stress with negative health outcomes, including cardiovascular disease (CVD), is extensively reported yet poorly defined. Stress is associated with a higher risk of hypertension, acute myocardial infarction, arrhythmogenesis, and heart failure. Stress mediates its effect through direct neuronal, endocrine, autonomic, and immune processes and indirectly by modifying lifestyle behaviors that promote CVD progression. Stress occurs when an individual perceives that internal or external demands exceed the capacity for an adaptive response. Psychologic stress is increasingly recognized in the atrial fibrillation (AF) population, although the pathophysiology remains unclear. There appears to be a bidirectional relationship between AF and stress with a complex interplay between the 2 entities. Stress modulates the immune and autonomic nervous systems, key drivers in AF initiation and potentiation. AF leads to increasing anxiety, psychologic distress, and suicidal ideation. Recently, lifestyle modification has emerged as the fourth pillar of AF management, with stress reduction a potential reversible risk factor and future target for intervention. This review examines proposed mechanisms linking AF and stress and explores stress reduction as an adjunct to the AF management armamentarium.

Post-traumatic stress disorder and its association with stroke and stroke risk factors: A literature review

Stroke is a major cause of mortality and disability globally that has multiple risk factors. A risk factor that has recently gained more attention is post-traumatic stress disorder (PTSD). Literature searches were carried out for updated PTSD information and for the relationship between PTSD and stroke. The review was divided into two sections, one exploring PTSD as an independent risk factor for stroke, with a second concentrating on PTSD's influence on stroke risk factors. The study presents accumulating evidence that shows traumatic stress predicts stroke and is also linked to many major stroke risk factors. The review contributes knowledge to stroke aetiology and acts as a reference for understanding the relationship between PTSD and stroke. The information presented indicates that screening and identification of traumatic experience would be beneficial for directing stroke patients to appropriate psychological and lifestyle interventions. In doing so, the burden of stroke may be reduced worldwide.

Trends in the Incidence of Sudden Deaths and Heart Diseases in Fukushima After the Great East Japan Earthquake

On March 11, 2011, a great earthquake, known as the Great East Japan Earthquake, hit northeastern Japan, resulting in a tsunami that caused a nuclear disaster, the Fukushima Daiichi Nuclear Power Plant accident, forcing about 160,000 people to evacuate. We, therefore, sought to examine the effects of this evacuation on the onset of cardiovascular diseases and sudden death (SD) in Fukushima Prefecture, three years after the earthquake. We divided the evacuation zone into two areas, whole evacuation zone (Area 1) and partial evacuation zone (Area 2), and we defined the north district of the prefecture as the control area (Area 3). We cross-referenced the death certificate data with data from the Fukushima Prefecture acute myocardial infarction registration survey. For each area, we tallied the number of people who fell into the SD, myocardial infarction (MI), and MI suspected groups. We calculated the age-adjusted incidence rates and analyzed the differences in the adjusted incidence rates across three years using a Poisson regression model. The age-adjusted death rate of the SD group was significantly higher in 2011 in all areas than in 2012 or 2013 (P < 0.05). The total death rate was higher in Area 1 in March 2011, just after the disaster, than in the other two areas. The rate of SD was also higher in Area 1 than in the other areas in March 2011. The incidence of sudden cardiac death might have increased just after the Great East Japan Earthquake in the evacuation area, but not in other areas in Fukushima Prefecture.

The long-term effects of early-life trauma on psychological, physical and physiological health among the elderly: the study of Holocaust survivors

Objectives: To study post-traumatic stress symptoms and post-traumatic growth and heart rate variability among elderly Holocaust survivors and a matched comparison group and the mediational effect of post-traumatic stress symptoms and post-traumatic growth on the association between Holocaust experience and heart rate variability. Method: 159 Holocaust survivors and 87 matched participants without Holocaust experience answered post-traumatic stress symptoms and post-traumatic growth questionnaires. Heart rate variability time and frequency parameters were measured for a subsample of N = 133. Results: Holocaust survivors reported higher levels of post-traumatic stress symptoms and post-traumatic growth. Most heart rate variability measures were similar in the two groups, except for better heart rate variability measured by the ratio of low frequency/high frequency among Holocaust survivors. Structural equation modeling showed that belonging to the Holocaust survivor group was associated with higher post-traumatic stress symptoms and higher post-traumatic growth, as well as better heart rate variability scores (standard deviation of normal to normal R-R intervals, high frequency and the ratio of low frequency/high frequency) through the mediation of post-traumatic stress symptoms and post-traumatic growth. Conclusions: The study emphasized the duality of the association between post-traumatic stress symptoms and post-traumatic growth and their integrated effect on heart rate variability.

Exercise Counteracts the Cardiotoxicity of Psychosocial Stress

Physical inactivity and psychosocial stress are prevalent in residents of the United States. The purpose of this article is to review the interaction between these 2 conditions and examine the effects of exercise on stress and cardiovascular (CV) health. A query of scientific references between 1974 to 2018 was performed using the PubMed search engine accessing the MEDLINE database using the search terms psychosocial stress, CV disease (CVD), physical activity, exercise, cardiac rehabilitation, and team sports. Psychosocial stress is a strong independent risk factor for adverse CV events. Conversely, people who experience CV events subsequently have drastically elevated rates of new-onset mental health disorders, including depression and anxiety. Psychosocial stress and CVD often trigger self-reinforcing feedback loops that can worsen mental health and cardiac prognosis. Exercise predictably improves CV health and prognosis and also is effective at lowering levels of psychosocial stress. Group exercise in particular seems to provide social support while at the same time boosting fitness levels and, thus, may be the single most important intervention for patients with concomitant CVD and emotional stress. Collaborative physical activity, such as group exercise, team sports, interactive physical play, and cardiac rehabilitation programs, have the potential to improve mental health and CV prognosis.

Psychosocial Stress and Cardiovascular Disease

PURPOSE OF REVIEW

This manuscript reviews the epidemiological data linking psychosocial stress to cardiovascular disease (CVD), describes recent advances in understanding the biological pathway between them, discusses potential therapies against stress-related CVD, and identifies future research directions.

RECENT FINDINGS

Metabolic activity of the amygdala (a neural center that is critically involved in the response to stress) can be measured on ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG-PET/CT) yielding a neurobiological signal that independently predicts subsequent CVD events. Furthermore, a serial pathway from ↑amygdalar activity → ↑hematopoietic tissue activity → ↑arterial inflammation → ↑CVD events has been elucidated, providing new insights into the mechanism linking stress to CVD. Psychosocial stress and stress conditions are independently associated with CVD in a manner that depends on the degree and duration of stress as well as the individual response to a stressor. Nevertheless, the fundamental biology remains incompletely defined, and stress is often confounded by adverse health behaviors. Thus, most clinical guidelines do not yet recognize psychosocial stress as an independent CVD risk factor or advocate for its treatment in CVD prevention. Clarification of this neurobiological pathway provides a better understanding of the underlying pathophysiology and suggests opportunities to develop novel preventive strategies and therapies.

Role of the autonomic nervous system and baroreflex in stress-evoked cardiovascular responses in rats

Restraint stress (RS) is an experimental model to study stress-related cardiovascular responses, characterized by sustained pressor and tachycardiac responses. We used pharmacologic and surgical procedures to investigate the role played by sympathetic nervous system (SNS) and parasympathetic nervous system (PSNS) in the mediation of stress-evoked cardiovascular responses. Ganglionic blockade with pentolinium significantly reduced RS-evoked pressor and tachycardiac responses. Intravenous treatment with homatropine methyl bromide did not affect the pressor response but increased tachycardia. Pretreatment with prazosin reduced the pressor and increased the tachycardiac response. Pretreatment with atenolol did not affect the pressor response but reduced tachycardia. The combined treatment with atenolol and prazosin reduced both pressor and tachycardiac responses. Adrenal demedullation reduced the pressor response without affecting tachycardia. Sinoaortic denervation increased pressor and tachycardiac responses. The results indicate that: (1) the RS-evoked cardiovascular response is mediated by the autonomic nervous system without an important involvement of humoral factors; (2) hypertension results primarily from sympathovascular and sympathoadrenal activation, without a significant involvement of the cardiac sympathetic component (CSNS); (3) the abrupt initial peak in the hypertensive response to restraint is sympathovascular-mediated, whereas the less intense but sustained hypertensive response observed throughout the remaining restraint session is mainly mediated by sympathoadrenal activation and epinephrine release; (4) tachycardia results from CSNS activation, and not from PSNS inhibition; (5) RS evokes simultaneous CSNS and PSNS activation, and heart rate changes are a vector of both influences; (6) the baroreflex is functional during restraint, and modulates both the vascular and cardiac responses to restraint.

Population-based incidence of sudden cardiac and unexpected death before and after the 2011 earthquake and tsunami in Iwate, northeast Japan

BACKGROUND

The aim of this study was to evaluate the temporal impact of the 2011 Japan earthquake and tsunami on the incidence of sudden cardiac and unexpected death (SCUD).

METHODS AND RESULTS

We surveyed the impact of the disaster on the incidence and clinical characteristics of SCUD in Iwate. To perform complete identification of SCUD for 8 weeks before and 40 weeks after the disaster, medical records and death certificates relevant to SCUD were surveyed in the study area. Compared with the previous year's rate, the incidence (per 10 000 person-year) of SCUD for the initial 4 weeks after the disaster (acute phase) was double (33.5 vs 18.9), and thereafter the rate returned to the previous level. Significant relationships were found between weekly numbers of SCUD and seismic activity (intensity, r=0.43; P<0.005: frequency, r=0.46; P<0.002). The standardized incidence ratio (SIR) of SCUD in the acute phase was significantly increased compared with that of previous years (1.71, 95% CI 1.33 to 2.16). Increased SIRs were predominantly found in female subjects (1.73, 95% CI 1.22 to 2.37), the elderly (1.73, 95% CI 1.29 to 2.27), and residents living in the tsunami-stricken area (1.83, 95% CI 1.33 to 2.46). In addition, SIRs for weekdays (1.71, 95% CI 1.28 to 2.24) and nights-mornings (2.09, 95% CI 1.48 to 2.86) were amplified.

CONCLUSIONS

The present results suggest that the magnitude of a disaster, related stress, and population aging may cause a temporary increase in the incidence of SCUD with amplification of ordinary weekly and circadian variations.

Relationship between stress and coronary heart disease

BACKGROUND

Coronary heart disease is the leading cause of death worldwide and accounts for 13.7% of deaths in countries like Pakistan. Its association with stress has not been well considered in our setup. Patients with coronary artery disease admitted for coronary artery bypass grafting may have a high prevalence of stress that might increase the risk of adverse outcomes.

METHODS

60 patients with coronary artery disease admitted to the Civil Hospital Karachi for coronary artery bypass graft surgery from January 1 to March 31, 2012, were evaluated using a stress evaluation scale.

RESULTS

Stress of varying degrees was found to be a significant independent risk factor in patients with coronary heart disease. Analysis of our collected sample of patients with stress showed 60% with high stress (p = 0.025) and 36.7% moderate stress (p = 0.0025). An appreciable relationship was found between stress and patient age, sex, body mass index, blood group, and the incidence of myocardial infarction.

CONCLUSION

Our study found evidence of an independent causative association between psychological stress and coronary heart disease, of a similar order to the more conventional coronary heart disease risk factors.

Acute changes in home blood pressure after the Great East Japan Earthquake among patients with chronic kidney disease in Fukushima City

BACKGROUND

Blood pressure (BP) transiently increases after major earthquakes. Although home BP increased in hypertensive patients after the Great East Japan Earthquake (measuring 9.0 on the Richter scale) on March 11th, 2011, such profiles in patients with chronic kidney disease (CKD) have not been investigated.

METHODS

This retrospective single-center observational study included 38 patients with CKD at the predialysis stage [male, n=27 (71%); mean age 66.0 years; mean estimated glomerular filtration rate (eGFR) 46.0 mL/min/1.73 m²] who lived in Fukushima City. We compared their morning BP between two and four weeks after the quake with that of a control group of 39 non-CKD patients with hypertension.

RESULTS

Systolic BP (SBP) remained elevated for one week after the quake in the CKD and non-CKD groups [before vs. after the quake 133.7±15.6 vs. 136.9±16.9 (p=0.017) and 129.9±7.8 vs. 133.3±9.3 mmHg (p=0.009), respectively]. Increases in SBP in the morning after the quake were statistically significant in the group with but not in that without CKD (7.1 and 3.4 mmHg; p=0.038 and 0.221, respectively). Multivariate analysis revealed that a low eGFR was an independent risk factor for elevated SBP after the quake.

CONCLUSIONS

The quake caused acute changes in the home BP and the fact that BP elevation correlated with renal function suggests a possible mechanism of CKD, such as enhanced activity of the sympathetic nervous system in such patients.

Psychological risk factors and cardiovascular disease: is it all in your head?

Psychological stress has been shown to be associated with cardiovascular disease. Over the past few decades, there has been an increasing interest in this relationship, leading to a growing pool of clinical and epidemiological data on the subject. Psychological stress has multiple etiologies, which include behavioral causes, acute events or stressors, and/or chronic stress. Cardiac rehabilitation and exercise therapy have been shown to provide protection in primary and secondary coronary heart disease prevention, as well as improve overall morbidity and mortality. In this article, we review the available data regarding the association between psychological stress and cardiovascular disease, as well as the impact of cardiac rehabilitation and exercise therapy on psychological stress-related cardiovascular events.

Top-down and bottom-up mechanisms in mind-body medicine: development of an integrative framework for psychophysiological research

It has become increasingly evident that bidirectional ("top-down and bottom-up") interactions between the brain and peripheral tissues, including the cardiovascular and immune systems, contribute to both mental and physical health. Therapies directed toward addressing functional links between mind/brain and body may be particularly effective in treating the range of symptoms associated with many chronic diseases. In this paper, we describe the basic components of an integrative psychophysiological framework for research aimed at elucidating the underlying substrates of mind-body therapies. This framework recognizes the multiple levels of the neuraxis at which mind-body interactions occur. We emphasize the role of specific fronto-temporal cortical regions in the representation and control of adverse symptoms, which interact reciprocally with subcortical structures involved in bodily homeostasis and responses to stress. Bidirectional autonomic and neuroendocrine pathways transmit information between the central nervous system and the periphery and facilitate the expression of affective, autonomic, hormonal, and immune responses. We propose that heart rate variability (HRV) and markers of inflammation are important currently available indices of central-peripheral integration and homeostasis within this homeostatic network. Finally, we review current neuroimaging and psychophysiological research from diverse areas of mind-body medicine that supports the framework as a basis for future research on the specific biobehavioral mechanisms of mind-body therapies.

Triggers and the onset of acute myocardial infarction

The onset of acute myocardial infarction (AMI) is a complex interplay of internal circadian factors and external physical and emotional triggers. These interactions may lead to rupture of an often nonocclusive vulnerable atherosclerotic coronary plaque with subsequent formation of an occlusive thrombus. The onset of AMI has a distinct pattern, with peak incidence within the first few hours after awakening, on certain days of the week, and in the winter months. Physical and emotional stresses are important triggers of acute cardiovascular events including AMI. Triggering events, internal changes, and external factors vary among different geographical, environmental, and ethnic regions. Life-style changes, pharmacotherapy, and psychologic interventions may potentially modify the response to, and protect against the effects of triggering events.

Psychological stress and cardiovascular disease

There is an enormous amount of literature on psychological stress and cardiovascular disease. This report reviews conceptual issues in defining stress and then explores the ramifications of stress in terms of the effects of acute versus long-term stressors on cardiac functioning. Examples of acute stressor studies are discussed in terms of disasters (earthquakes) and in the context of experimental stress physiology studies, which offer a more detailed perspective on underlying physiology. Studies of chronic stressors are discussed in terms of job stress, marital unhappiness, and burden of caregiving. From all of these studies there are extensive data concerning stressors' contributions to diverse pathophysiological changes including sudden death, myocardial infarction, myocardial ischemia, and wall motion abnormalities, as well as to alterations in cardiac regulation as indexed by changes in sympathetic nervous system activity and hemostasis. Although stressors trigger events, it is less clear that stress "causes" the events. There is nonetheless overwhelming evidence both for the deleterious effects of stress on the heart and for the fact that vulnerability and resilience factors play a role in amplifying or dampening those effects. Numerous approaches are available for stress management that can decrease patients' suffering and enhance their quality of life.

The cardiovascular toll of stress

Psychological stress elicits measurable changes in sympathetic-parasympathetic balance and the tone of the hypothalamic-pituitary-adrenal axis, which might negatively affect the cardiovascular system both acutely-by precipitating myocardial infarction, left-ventricular dysfunction, or dysrhythmia; and chronically-by accelerating the atherosclerotic process. We provide an overview of the association between stress and cardiovascular morbidity, discuss the mechanisms for this association, and address possible therapeutic implications.

Behavioral cardiology: recognizing and addressing the profound impact of psychosocial stress on cardiovascular health

Psychosocial stress exerts independent adverse effects on cardiovascular health. The recent INTERHEART study reported that psychosocial stress accounted for approximately 30% of the attributable risk of acute myocardial infarction. Prospective studies consistently indicate that hostility, depression, and anxiety are all related to increased risk of coronary heart disease and cardiovascular death. A sense of hopelessness, in particular, appears to be strongly correlated with adverse cardiovascular outcomes. Time urgency and impatience have not been consistently related to risk of coronary disease, but do increase the likelihood of developing hypertension. Psychosocial stress appears to adversely affect autonomic and hormonal homeostasis, resulting in metabolic abnormalities, inflammation, insulin resistance, and endothelial dysfunction. Additionally, stress is often associated with self-destructive behavior and noncompliance with medications. Psychosocial stress is a highly modifiable risk and many factors have been shown to be protective. These include psychosocial support, regular exercise, stress reduction training, sense of humor, optimism, altruism, faith, and pet ownership. Simple screening questions are available to reliably indicate a patient at risk for psychosocial stress-related health problems.

Psychosocial stress and cardiovascular disease: How to heal a broken heart

Psychosocial stress induces adverse changes in autonomic tone accounting for substantial but modifiable cardiovascular risk. Various factors, including depression, social isolation, hostility and anxiety increase cardiovascular risk, whereas social support, altruism, faith and optimism reduce risk.

Autonomic tone as a cardiovascular risk factor: the dangers of chronic fight or flight

Chronic imbalance of the autonomic nervous system is a prevalent and potent risk factor for adverse cardiovascular events, including mortality. Although not widely recognized by clinicians, this risk factor is easily assessed by measures such as resting and peak exercise heart rate, heart rate recovery after exercise, and heart rate variability. Any factor that leads to inappropriate activation of the sympathetic nervous system can be expected to have an adverse effect on these measures and thus on patient outcomes, while any factor that augments vagal tone tends to improve outcomes. Insulin resistance, sympathomimetic medications, and negative psychosocial factors all have the potential to affect autonomic function adversely and thus cardiovascular prognosis. Congestive heart failure and hypertension also provide important lessons about the adverse effects of sympathetic predominance, as well as illustrate the benefits of beta-blockers and angiotensin-converting enzyme inhibitors, 2 classes of drugs that reduce adrenergic tone. Other interventions, such as exercise, improve cardiovascular outcomes partially by increasing vagal activity and attenuating sympathetic hyperactivity.