Platelet aggregation and mental stress induced myocardial ischemia: Results from the Responses of Myocardial Ischemia to Escitalopram Treatment (REMIT) study

Stress and cardiovascular disease: an update

Psychological stress is generally accepted to be associated with an increased risk of cardiovascular disease (CVD), but results have varied in terms of how stress is measured and the strength of the association. Additionally, the mechanisms and potential causal links have remained speculative despite decades of research. The physiological responses to stress are well characterized, but their contribution to the development and progression of CVD has received little attention in empirical studies. Evidence suggests that physiological responses to stress have a fundamental role in the risk of CVD and that haemodynamic, vascular and immune perturbations triggered by stress are especially implicated. Stress response physiology is regulated by the corticolimbic regions of the brain, which have outputs to the autonomic nervous system. Variation in these regulatory pathways might explain interindividual differences in vulnerability to stress. Dynamic perturbations in autonomic, immune and vascular functions are probably also implicated as CVD risk mechanisms of chronic, recurring and cumulative stressful exposures, but more data are needed from prospective studies and from assessments in real-life situations. Psychological assessment remains insufficiently recognized in clinical care and prevention. Although stress-reduction interventions might mitigate perceived stress levels and potentially reduce cardiovascular risk, more data from randomized trials are needed.

Selective serotonin reuptake inhibitors regulate the interrelation between 5-HT and inflammation after myocardial infarction

BACKGROUND

Acute myocardial infarction (AMI) is a main cause of death all around the world. There is a close relationship between myocardial infarction (MI) and depression. MI patients with untreated depression had higher mortality than those without depression. Therefore, this study aimed to explore the effect of escitalopram in treating a model under MI and unpredictable chronic mild stress (UCMS).

METHODS

Male C57BL/6J mice were treated with sham surgery, or MI surgery, or UCMS, or escitalopram (ES) for a consecutive two weeks. And the mice were divided into Sham group, MI group, MI + UCMS group, MI + UCMS + ES group (n = 8 in each group). After treatment, the mice went through open field test for anxiety behavior, sucrose preference test for depressive behavior. After sacrificed, the blood, heart, hippocampus, and cortex were collected.

RESULTS

The escitalopram badly increased the area of cardiac fibrosis size. The sucrose preference test demonstrated that escitalopram treatment showed significant effect in improving depressive behaviors of mice under MI + UCMS. The potential mechanism involved the interrelation between 5-HT system and inflammation. MI significantly affected the level of cardiac SERT. Both UCMS and ES significantly affected the level of cortex TNF-α. UCMS significantly affected the level of cardiac IL-33. In the hippocampus tissue, TNF-α was positively correlated with SERT, and IL-10 was positively correlated with SERT. In the cortex tissue, IL-33 was positively correlated with 5-HT4R, and sST2 was positively correlated with 5-HT.

CONCLUSIONS

Two-week escitalopram treatment might worsen myocardial infarction. But escitalopram could benefit depressive behaviors, which may be related with the interrelationship between the 5-HT system and inflammatory factors in the brain.

Brain-heart connections in stress and cardiovascular disease: Implications for the cardiac patient

The influence of psychological stress on the physiology of the cardiovascular system, and on the etiology and outcomes of cardiovascular disease (CVD) has been the object of intense investigation. As a whole, current knowledge points to a "brain-heart axis" that is especially important in individuals with pre-existing CVD. The use of acute psychological stress provocation in the laboratory has been useful to clarify the effects of psychological stress on cardiovascular physiology, immune function, vascular reactivity, myocardial ischemia, neurobiology and cardiovascular outcomes. An emerging paradigm is that dynamic perturbations of physiological and molecular pathways during stress or negative emotions are important in influencing cardiovascular outcomes, and that some patient subgroups, such as women, patients with an early-onset myocardial infarction, and patients with adverse psychosocial exposures, may be at especially high risk for these effects. This review summarizes recent knowledge on mind-body connections in CVD among cardiac patients and highlights important pathways of risk which could become the object of future intervention efforts. As a whole, this research suggests that an integrated study of mind and body is necessary to fully understand the determinants and consequences of CVD.

Effects of clinical depression on left ventricular dysfunction in patients with acute coronary syndrome

Depression is associated with heart failure independent of traditional cardiovascular disease risk factors. Enhanced platelet activation has been suggested as a potential mechanism and has been associated with negative inotropic effects that can affect left ventricular ejection fraction (LVEF). We examined 131 consecutive acute coronary syndrome (ACS) patients to assess whether depression increased the risk for developing LV dysfunction, and to determine the effects of platelet serotonin signaling in this relationship. Major depression was assessed using the Structured Clinical Interview and depressive symptoms were measured using the Beck Depression Inventory (BDI), with BDI ≥ 10 defined as abnormal. LV dysfunction was defined as LVEF ≤ 45%. Platelet serotonin response was measured by serotonin augmented platelet aggregation and platelet serotonin receptor density. Mean age of ACS participants was 59 years, 78.6% male and 74.0% Caucasian. 34.4% of patients had a reduced LVEF ≤ 45% on presentation. Almost half (47.0%) of patients had BDI ≥ 10 and 18.0% had major depressive disorder. Platelet serotonin response was found to be augmented in depressed patients with low LVEF compared to depressed patients with normal LVEF (p < 0.020). However, the presence of LV dysfunction was found to be similar in both depressed (32.3%) and non-depressed (36.2%) patients (p = 0.714). This suggests alternative factors contribute to poor cardiovascular outcomes in depressed patients that are independent of LV function in post ACS patients.

Research progress regarding the diagnosis and treatment of mental stress-induced myocardial ischemia

Myocardial ischemia resulting from psychological stress [mental stress-induced myocardial ischemia (MSIMI)] refers to the condition wherein psychosocial and psychological stimulations cause myocardial ischemia in patients with coronary heart disease, which is different from drug-induced myocardial ischemia. Therefore, this condition often escapes diagnosis, portends clinical risk, and affects the quality of life of MSIMI survivors. MSIMI is closely related to the poor prognosis of cardiovascular diseases, especially in young women, according to recent randomized, controlled trials (RCTs) on MSIMI. These RCTs involved different sample sizes, interventional measures, and detection techniques. Moreover, differences exist regarding the prevalence rate, distribution characteristics, possible pathogenesis, and clinical significance. Nevertheless, currently, the diagnostic criteria, pathogenesis, and treatment of MSIMI are still in the clinical exploration stage. Hence, considering recent RCTs, this paper summarizes the research status of MSIMI from the aspects of pathogenesis, diagnosis, and treatment strategies to provide a theoretical basis for the follow-up diagnostic methods and treatment guidelines for MSIMI.

Peripheral Vasoconstriction During Mental Stress and Adverse Cardiovascular Outcomes in Patients With Coronary Artery Disease

RATIONALE

Excessive vasoconstriction in response to mental stress may be a potential mechanism by which acute psychological stress leads to adverse cardiac events.

OBJECTIVES

We investigated whether excessive digital vasoconstriction during acute mental stress predicts adverse cardiovascular outcomes among patients with coronary artery disease.

METHODS AND RESULTS

Five hundred forty-nine patients with stable coronary artery disease (age 63±9, 76% male, 29% black) underwent mental stress testing with a standardized public speaking stressor and followed prospectively for cardiovascular end points. Digital pulse wave amplitude was continuously measured using peripheral artery tonometry (PAT, Itamar Inc). Stress/rest PAT ratio (sPAT) of pulse wave amplitude during mental stress/baseline was calculated and dichotomized by the median value into low and high sPAT ratio groups. Upon 3-year follow-up, Fine and Gray's subdistribution hazard ratios were used to examine the association between sPAT ratio and the composite end point of cardiovascular death, myocardial infarction, revascularization, and hospitalization for heart failure. The median sPAT ratio was 0.68 (interquartile range, 0.48-0.88), indicating 32% vasoconstriction with mental stress. Men were more likely to have low sPAT ratio than women (odds ratio, 1.79; P=0.007) while those on β-blockers were less likely to have low sPAT ratio (odds ratio, 0.52; P=0.003). After adjusting for demographic and cardiovascular risk factors, medications, and rate-pressure product change during mental stress, those with low sPAT ratio were at significantly higher risk of adverse outcomes (subdistribution hazard ratio, 1.77 [95% CI, 1.12-2.80]).

CONCLUSIONS

Greater peripheral vasoconstriction with mental stress, denoted by a low sPAT ratio, is associated with a higher risk of adverse cardiovascular outcomes in patients with coronary artery disease.

Potential predictors for mental stress-induced myocardial ischemia in patients with coronary artery disease

BACKGROUND

Mental stress-induced myocardial ischemia (MSIMI) is closely associated with adverse cardiac events in patients with coronary artery disease (CAD) and we aimed to determine whether biomarkers and blood pressure could be potential predictors of MSIMI.

METHODS

This study enrolled 82 patients with documented CAD between June 1, 2017 and November 9, 2017. Patient blood samples were obtained at resting period and at the end of mental arithmetic. Then, patients were assigned to MSIMI positive group and MSIMI negative group. The main statistical methods included linear regression, receiver operating characteristic (ROC) curves, and logistic regression.

RESULTS

Patients with CAD with MSIMI had significantly greater median resting N-terminal pro-brain natriuretic peptide (NT-proBNP, 141.02 [45.85-202.76] pg/mL vs. 57.95 [27.06-117.64] pg/mL; Z = -2.23, P = 0.03) and mean systolic blood pressure (SBP) (145.56 ± 16.87 mmHg vs. 134.92 ± 18.16 mmHg, Z = -2.13, P = 0.04) when compared with those without MSIMI. After 5-min mental stress task, those who developed MSIMI presented higher elevation of median post-stressor high sensitivity cardiac troponin I (hs-cTnI, 0.020 [0.009-0.100] ng/mL vs. 0.009 [0.009-0.010] ng/mL; Z = -2.45, P = 0.01), post-stressor NT-proBNP (138.96 [39.93-201.56] pg/mL vs. 61.55 [25.66-86.50] pg/mL; Z = -2.15, P = 0.03) compared with those without MSIMI. Using the ROC curves, and after the adjustment for basic characteristics, the multiple logistic regression analysis showed that patients presenting a post-stressor hs-cTnI ≥ 0.015 ng/mL had seven-fold increase in the risk of developing MSIMI (odds ratio [OR]: 7.09; 95% confidence interval [CI]: 1.65-30.48; P = 0.009), a rest NT-proBNP ≥ 80.51 pg/mL had nearly eight-fold increase (OR: 7.85; 95% CI: 1.51-40.82; P = 0.014), a post-stressor NT-proBNP ≥ 98.80 pg/mL had 35-fold increase (OR: 34.96; 95% CI: 3.72-328.50; P = 0.002), a rest SBP ≥ 129.50 mmHg had 11-fold increase (OR: 11.42; 95% CI: 1.21-108.17; P = 0.034).

CONCLUSIONS

The present study shows that CAD patients with higher hs-cTnI level, and/or greater NT-proBNP and/or SBP are at higher risk of suffering from MSIMI when compared with those without MSIMI, indicating that hs-cTnI, NT-proBNP, SBP might be potential predictors of MSIMI.

Mental stress-induced left ventricular dysfunction and adverse outcome in ischemic heart disease patients

Aims Mental stress-induced myocardial ischemia (MSIMI) occurs in up to 70% of patients with clinically stable ischemic heart disease and is associated with increased risk of adverse prognosis. We aimed to examine the prognostic value of indices of MSIMI and exercise stress-induced myocardial ischemia (ESIMI) in a population of ischemic heart disease patients that was not confined by having a recent positive physical stress test. Methods and results The Responses of Mental Stress Induced Myocardial Ischemia to Escitalopram Treatment (REMIT) study enrolled 310 subjects who underwent mental and exercise stress testing and were followed annually for a median of four years. Study endpoints included time to first and total rate of major adverse cardiovascular events, defined as all-cause mortality and hospitalizations for cardiovascular causes. Cox and negative binomial regression adjusting for age, sex, resting left ventricular ejection fraction, and heart failure status were used to examine associations of indices of MSIMI and ESIMI with study endpoints. The continuous variable of mental stress-induced left ventricular ejection fraction change was significantly associated with both endpoints (all p values < 0.05). For every reduction of 5% in left ventricular ejection fraction induced by mental stress, patients had a 5% increase in the probability of a major adverse cardiovascular event at the median follow-up time and a 20% increase in the number of major adverse cardiovascular events endured over the follow-up period of six years. Indices of ESIMI did not predict endpoints ( ps > 0.05). Conclusion In patients with stable ischemic heart disease, mental, but not exercise, stress-induced left ventricular ejection fraction change significantly predicts risk of future adverse cardiovascular events.

Emotional triggering of cardiac dysfunction: the present and future

Mental stress and emotional arousal can act as triggers of acute myocardial infarction and other adverse cardiovascular outcomes. Experimental research examining mechanisms of the adverse interplay between mind and heart has led to the discovery of mental stress-induced cardiac dysfunction or myocardial ischemia (MSIMI). Evidence about the prevalence, clinical significance, and mechanistic bases of MSIMI outlines a wide range of central and peripheral bio-pathologic processes that are associated with emotions and behaviors. MSIMI is recognized as an integrated and intermediate biomarker underpinning the negative mind-heart interplay. Particularly, MSIMI research paves the way toward investigations aiming more specifically at recognizing the susceptibilities of individuals who are prone to respond adversely to the psycho-social-environmental stress. This article reviews recent literature on MSIMI research following the comprehensive review of Strike and Steptoe Eur Heart J 24:690-703, 2003. Further, this article outlines the main steps in the identification of the specific bio-pathologic manifestations of the cardiovascular system to emotional stress. Finally, a speculative description is provided of future directions in better searching for areas that may be critical targets in resolving adverse mind-heart interplays.