Variability of myocardial ischemic responses to mental versus exercise or adenosine stress in patients with coronary artery disease

Quantitation of diffuse myocardial ischemia with mental stress and its association with cardiovascular events in individuals with recent myocardial infarction

Microcirculatory dysfunction during psychological stress may lead to diffuse myocardial ischemia. We developed a novel quantification method for diffuse ischemia during mental stress (dMSI) and examined its relationship with outcomes after a myocardial infarction (MI). We studied 300 patients ≤ 61 years of age (50% women) with a recent MI. Patients underwent myocardial perfusion imaging with mental stress and were followed for 5 years. dMSI was quantified from cumulative count distributions of rest and stress perfusion. Focal ischemia was defined in a conventional fashion. The main outcome was a composite outcome of recurrent MI, heart failure hospitalizations, and cardiovascular death. A dMSI increment of 1 standard deviation was associated with a 40% higher risk for adverse events (HR 1.4, 95% CI 1.2-1.5). Results were similar after adjustment for viability, demographic and clinical factors and focal ischemia. In sex-specific analysis, higher levels of dMSI (per standard deviation increment) were associated with 53% higher risk of adverse events in women (HR 1.5, 95% CI 1.2-2.0) but not in men (HR 0.9, 95% CI 0.5-1.4), P 0.001. A novel index of diffuse ischemia with mental stress was associated with recurrent events in women but not in men after MI.

Emerging misunderstood presentations of cardiovascular disease in young women

BACKGROUND

Cardiovascular disease (CVD) remains the leading cause of death for females in the United States accounting for over 412 000 female deaths in 2016. CVD mortality in young women <55 years old remains significantly high and greater than that in men.

HYPOTHESIS

There is a void with regards to awareness of CVD in women. Many traditional CVD risk estimate tools fail to identify the "at risk" female and is true for the young female patient. There needs to be a shift in focus from looking for the vulnerable plaque to looking for the "at risk" patient.

METHODS

This review outlines the emerging misunderstood presentations of CVD in young women which include certain categories of myocardial infarction (MI) with non-obstructive coronary arteries (MINOCA), such as spontaneous coronary artery dissection (SCAD), as well as the more stable myocardial ischemia with non-obstructive coronary arteries (INOCA) category focusing on mental stress-induced myocardial ischemia (MSIMI).

RESULTS

The prevalence of MINOCA in patients presenting with MI is greater in women. In younger women with CVD, SCAD is an emerging misunderstood presentation in this group of patients with type 2 SCAD being the most common form. MSIMI, a form of INOCA, is more common in women with CVD.

CONCLUSIONS

There are emerging misunderstood factors that are prevalent in young women, such as SCAD and MSIMI. It is important to recognize their presentations in young women to prevent misdiagnosis, missed diagnosis as well as mismanagement of these patients to improve their clinical outcomes.

Depression, anxiety, and stress in patients with coronary heart disease

The analytical paper summarized the results of recent studies of an association of depression, anxiety, and stress with coronary heart disease (CHD). Mental disorders are shown to be associated with increased risk of CHD and to worsen the course of coronary disease. Antidepressants and psychotherapy improve the control of mental disorders, quality of life, and, in some cases, have a positive impact on the course of coronary disease.

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.

High Concordance Between Mental Stress-Induced and Adenosine-Induced Myocardial Ischemia Assessed Using SPECT in Heart Failure Patients: Hemodynamic and Biomarker Correlates

Mental stress can trigger myocardial ischemia, but the prevalence of mental stress-induced ischemia in congestive heart failure (CHF) patients is unknown. We characterized mental stress-induced and adenosine-induced changes in myocardial perfusion and neurohormonal activation in CHF patients with reduced left-ventricular function using SPECT to precisely quantify segment-level myocardial perfusion.

METHODS

Thirty-four coronary artery disease patients (mean age±SD, 62±10 y) with CHF longer than 3 mo and ejection fraction less than 40% underwent both adenosine and mental stress myocardial perfusion SPECT on consecutive days. Mental stress consisted of anger recall (anger-provoking speech) followed by subtraction of serial sevens. The presence and extent of myocardial ischemia was quantified using the conventional 17-segment model.

RESULTS

Sixty-eight percent of patients had 1 ischemic segment or more during mental stress and 81% during adenosine. On segment-by-segment analysis, perfusion with mental stress and adenosine were highly correlated. No significant differences were found between any 2 time points for B-type natriuretic peptide, tumor necrosis factor-α, IL-1b, troponin, vascular endothelin growth factor, IL-17a, matrix metallopeptidase-9, or C-reactive protein. However, endothelin-1 and IL-6 increased, and IL-10 decreased, between the stressor and 30 min after stress. Left-ventricular end diastolic dimension was 179±65 mL at rest and increased to 217±71 after mental stress and 229±86 after adenosine (P<0.01 for both). Resting end systolic volume was 129±60 mL at rest and increased to 158±66 after mental stress (P<0.05) and 171±87 after adenosine (P<0.07), with no significant differences between adenosine and mental stress. Ejection fraction was 30±12 at baseline, 29±11 with mental stress, and 28±10 with adenosine (P=not significant).

CONCLUSION

There was high concordance between ischemic perfusion defects induced by adenosine and mental stress, suggesting that mental stress is equivalent to pharmacologic stress in eliciting clinically significant myocardial perfusion defects in CHF patients. Cardiac dilatation suggests clinically important changes with both conditions. Psychosocial stressors during daily life may contribute to the ischemic burden of CHF patients with coronary artery disease.

Confluence of depression and acute psychological stress among patients with stable coronary heart disease: effects on myocardial perfusion

Background

Depression is prevalent in coronary heart disease (CHD) patients and increases risk for acute coronary syndrome (ACS) recurrence and mortality despite optimal medical care. The pathways underlying this risk remain elusive. Psychological stress (PS) can provoke impairment in myocardial perfusion and trigger ACS. A confluence of acute PS with depression might reveal coronary vascular mechanisms of risk. We tested whether depression increased risk for impaired myocardial perfusion during acute PS among patients with stable CHD.

Methods and Results

Patients (N=146) completed the Beck Depression Inventory‐I (BDI‐I), a measure of depression linked to recurrent ACS and post‐ACS mortality, and underwent single‐photon emission computed tomography myocardial perfusion imaging at rest and during acute PS. The likelihood of new/worsening impairment in myocardial perfusion from baseline to PS as a function of depression severity was tested. On the BDI‐I, 41 patients scored in the normal range, 48 in the high normal range, and 57 in the depressed range previously linked to CHD prognosis. A BDI‐I score in the depressed range was associated with a significantly greater likelihood of new/worsening impairment in myocardial perfusion from baseline to PS (odds ratio =2.89, 95% CI: 1.26 to 6.63, P=0.012). This remained significant in models controlling ACS recurrence/mortality risk factors and medications. There was no effect for selective serotonin reuptake inhibitor medications.

Conclusions

Depressed patients with CHD are particularly susceptible to impairment in myocardial perfusion during PS. The confluence of PS with depression may contribute to a better understanding of the depression‐associated risk for ACS recurrence and mortality.

Sex differences in mental stress-induced myocardial ischemia in young survivors of an acute myocardial infarction

OBJECTIVES

Emotional stress may disproportionally affect young women with ischemic heart disease. We sought to examine whether mental stress-induced myocardial ischemia (MSIMI), but not exercise-induced ischemia, is more common in young women with previous myocardial infarction (MI) than in men.

METHODS

We studied 98 post-MI patients (49 women and 49 men) aged 38 to 60 years. Women and men were matched for age, MI type, and months since MI. Patients underwent technetium-99m sestamibi perfusion imaging at rest, after mental stress, and after exercise/pharmacological stress. Perfusion defect scores were obtained with observer-independent software. A summed difference score (SDS), the difference between stress and rest scores, was used to quantify ischemia under both stress conditions.

RESULTS

Women 50 years or younger, but not older women, showed a more adverse psychosocial profile than did age-matched men but did not differ for conventional risk factors and tended to have less angiographic coronary artery disease. Compared with age-matched men, women 50 years or younger exhibited a higher SDS with mental stress (3.1 versus 1.5, p = .029) and had twice the rate of MSIMI (SDS ≥ 3; 52% versus 25%), whereas ischemia with physical stress did not differ (36% versus 25%). In older patients, there were no sex differences in MSIMI. The higher prevalence of MSIMI in young women persisted when adjusting for sociodemographic and life-style factors, coronary artery disease severity, and depression.

CONCLUSIONS

MSIMI post-MI is more common in women 50 years or younger compared with age-matched men. These sex differences are not observed in post-MI patients who are older than 50 years.

A study of myocardial perfusion in patients with panic disorder and low risk coronary artery disease after 35% CO2 challenge

BACKGROUND

We have previously reported that 35% CO2 challenge induced myocardial ischemia in 81% of coronary artery disease (CAD) patients with comorbid panic disorder (PD) and previous positive nuclear exercise stress tests. However, it is yet unclear whether this is the case among CAD patients with PD and normal nuclear exercise stress test results. We hypothesized that a potent mental stressor such as a panic challenge among CAD patients with PD would also induce ischemia in patients with normal exercise stress tests.

METHODS

Forty-one coronary artery disease patients with normal nuclear exercise stress tests (21 patients with PD and 20 without PD) were submitted to a well-established panic challenge test (with 1 vital capacity inhalation of a gas mixture containing 35% CO2 and 65% O2) and injected with Tc-99m-tetrofosmin (Myoview), upon inhalation. Single photon emission computed tomography imaging was used to assess per-panic challenge reversible myocardial ischemia and HR, BP, and a 12 lead ECG was continuously measured during the procedure.

RESULTS

Fifty-eight percent of panic disorder patients (12/21) had a panic attack during the panic challenge vs 15% (3/20) of controls (p=0.005). Only 10% of patients in each group displayed myocardial ischemia per panic challenge.

CONCLUSIONS

These findings suggest that panic attacks among panic disorder patients with lower-risk coronary artery disease may not confer a risk for myocardial ischemia.

Myocardial ischemia and angiotensin-converting enzyme inhibition: comparison of ischemia during mental and physical stress

OBJECTIVE

Mental stress provokes myocardial ischemia in many patients with stable coronary artery disease (CAD). Mental stress-induced myocardial ischemia (MSIMI) portends a worse prognosis, independent of standard cardiac risk factors or outcome of traditional physical stress testing. Angiotensin II plays a significant role in the physiological response to stress, but its role in MSIMI remains unknown. Our aim was to evaluate whether the use of angiotensin-converting enzyme inhibitors (ACEIs) is associated with a differential effect on the incidence of MSIMI compared with ischemia during physical stress.

METHODS

Retrospective analysis of 218 patients with stable CAD, including 110 on ACEI, was performed. 99m-Tc-sestamibi myocardial perfusion imaging was used to define ischemia during mental stress, induced by a standardized public speaking task, and during physical stress, induced by either exercise or adenosine.

RESULTS

Overall, 40 patients (18%) developed MSIMI and 80 patients (37%) developed ischemia during physical stress. MSIMI occurred less frequently in patients receiving ACEIs (13%) compared with those not on ACEIs (24%; p = .030, adjusted odds ratio = 0.42, 95% confidence interval = 0.19-0.91). In contrast, the frequency of myocardial ischemia during physical stress testing was similar in both groups (39% versus 35% in those on and not on ACEIs, respectively); adjusted odds ratio = 0.91, 95% confidence interval = 0.48-1.73).

CONCLUSION

In this retrospective study, patients using ACEI therapy displayed less than half the risk of developing ischemia during mental stress but not physical stress. This possible beneficial effect of ACEIs on MSIMI may be contributing to their salutary effects in CAD.

Myocardial ischemia during mental stress: role of coronary artery disease burden and vasomotion

Background

Mental stress–induced myocardial ischemia (MSIMI) is associated with adverse prognosis in patients with coronary artery disease (CAD), yet the mechanisms underlying this phenomenon remain unclear. We hypothesized that compared with exercise/pharmacological stress–induced myocardial ischemia (PSIMI) that is secondary to the atherosclerotic burden of CAD, MSIMI is primarily due to vasomotor changes.

Methods and Results

Patients with angiographically documented CAD underwent ^99mTc‐sestamibi myocardial perfusion imaging at rest and following both mental and physical stress testing, performed on separate days. The severity and extent of CAD were quantified using the Gensini and Sullivan scores. Peripheral arterial tonometry (Itamar Inc) was used to assess the digital microvascular tone during mental stress as a ratio of pulse wave amplitude during speech compared with baseline. Measurements were made in a discovery sample (n=225) and verified in a replication sample (n=159). In the pooled (n=384) sample, CAD severity and extent scores were not significantly different between those with and without MSIMI, whereas they were greater in those with compared with those without PSIMI (P<0.04 for all). The peripheral arterial tonometry ratio was lower in those with compared with those without MSIMI (0.55±0.36 versus 0.76±0.52, P=0.009). In a multivariable analysis, the peripheral arterial tonometry ratio was the only independent predictor of MSIMI (P=0.009), whereas angiographic severity and extent of CAD independently predicted PSIMI.

Conclusions

The degree of digital microvascular constriction, and not the angiographic burden of CAD, is associated with MSIMI. Varying causes of MSIMI compared with PSIMI may require different therapeutic interventions that require further study.

Mental stress and ischemic heart disease: evolving awareness of a complex association

The connection between cardiovascular disease and psychosocial risk factors has been the subject of an ever-growing body of literature over the last 50 years. Studies on the role of negative emotions, personality traits, chronic stress and social determinants have brought to light their possible role in triggering acute coronary syndromes, although further studies are required to clarify controversial results regarding the association between cardiovascular risk and important psychological problems such as depression and anxiety. The recognition of the role of emotional events in acute coronary syndromes paved the way for provocation experiments, aimed at inducing mental stress in a controlled setting and then documenting reversible impairment of myocardial perfusion, depolarization anomalies and arrhythmias. This ultimately led to the formalization of the concept of mental stress-induced myocardial ischemia. Accumulating evidence on the mechanistic bases of such phenomena outline a wide range of central and peripheral physiological changes associated with emotions and behaviors, whose effects are exerted on the cardiovascular system, sympathetic nervous system and the hypothalamus-hypophysis neuroendocrine axis. This article outlines the main steps in the identification of psychological aspects as cardiovascular risk factors and emphasizes the relevance of emotional stress as a trigger of acute cardiovascular events. Finally, a description is provided of the pathophysiological mechanisms behind mental stress-induced myocardial ischemia and pathways connecting the heart and brain.

Psychic trauma as cause of death

AIM

of study Psychic trauma is described as the action of 'an emotionally overwhelming factor' capable of causing neurovegetative alterations leading to transitory or persisting bodily changes. The medico-legal concept of psychic trauma and its definition as a cause in penal cases is debated. The authors present three cases of death after psychic trauma, and discuss the definition of cause within the penal ambit of identified 'emotionally overwhelming factors'.

MATERIALS AND METHODS

The methodological approach to ascertainment and criterion-based assessment in each case involved the following phases: (1) examination of circumstantial evidence, clinical records and documentation; (2) autopsy; (3) ascertainment of cause of death; and (4) ascertainment of psychic trauma, and its coexisting relationship with the cause of death.

RESULTS

The results and assessment of each of the three cases are discussed from the viewpoint of the causal connotation of psychic trauma. In the cases presented, psychic trauma caused death, as deduced from assessment of the type of externally caused emotional insult, the subjects' personal characteristics and the circumstances of the event causing death.

CONCLUSIONS

In cases of death due to psychic trauma, careful methodological ascertainment is essential, with the double aim of defining 'emotionally overwhelming factors' as a significant cause of death from the penal point of view, and of identifying the responsibility of third parties involved in the death event and associated dynamics of homicide.

Association between anxiety disorder and the extent of ischemia observed in cardiac syndrome X

BACKGROUND

A possible link between the heart and brain has been reported for cardiac syndrome X. Anxiety disorder could be a pathophysiological mechanism for this cardiac chest pain. To the authors' knowledge, a quantitative analysis correlating anxiety with the extent of ischemia has not been done.

METHODS AND RESULTS

In this pilot study, we evaluated 20 patients with typical chest pain and completely normal coronary angiograms. These patients were screened with the State Scale and Trait Scale of the State-Trait Anxiety Inventory (STAI). All patients underwent myocardial perfusion scintigraphic imaging. The scintigrams were scored by three experienced readers having no knowledge of the STAI screening results. Patients with a low trait anxiety had significantly less ischemic segments on the myocardial perfusion imaging than patients with a high trait anxiety (1.8 +/- 1.9 vs 3.5 +/- 0.6, P < .05). For state anxiety, no significant differences could be found.

CONCLUSION

Cardiac syndrome X patients with high trait anxiety are at risk of having more ischemia.