Relationship among mental stress-induced ischemia and ischemia during daily life and during exercise: the Psychophysiologic Investigations of Myocardial Ischemia (PIMI) study

Mental Stress and Cardiovascular Health-Part I

Epidemiological studies have shown that a substantial proportion of acute coronary events occur in individuals who lack the traditional high-risk cardiovascular (CV) profile. Mental stress is an emerging risk and prognostic factor for coronary artery disease and stroke, independently of conventional risk factors. It is associated with an increased rate of CV events. Acute mental stress may develop as a result of anger, fear, or job strain, as well as consequence of earthquakes or hurricanes. Chronic stress may develop as a result of long-term or repetitive stress exposure, such as job-related stress, low socioeconomic status, financial problems, depression, and type A and type D personality. While the response to acute mental stress may result in acute coronary events, the relationship of chronic stress with increased risk of coronary artery disease (CAD) is mainly due to acceleration of atherosclerosis. Emotionally stressful stimuli are processed by a network of cortical and subcortical brain regions, including the prefrontal cortex, insula, amygdala, hypothalamus, and hippocampus. This system is involved in the interpretation of relevance of environmental stimuli, according to individual’s memory, past experience, and current context. The brain transduces the cognitive process of emotional stimuli into hemodynamic, neuroendocrine, and immune changes, called fight or flight response, through the autonomic nervous system and the hypothalamic–pituitary–adrenal axis. These changes may induce transient myocardial ischemia, defined as mental stress-induced myocardial ischemia (MSIMI) in patients with and without significant coronary obstruction. The clinical consequences may be angina, myocardial infarction, arrhythmias, and left ventricular dysfunction. Although MSIMI is associated with a substantial increase in CV mortality, it is usually underestimated because it arises without pain in most cases. MSIMI occurs at lower levels of cardiac work than exercise-induced ischemia, suggesting that the impairment of myocardial blood flow is mainly due to paradoxical coronary vasoconstriction and microvascular dysfunction.

Cardiovascular Imaging of Biology and Emotion: Considerations Toward a New Paradigm

Central activation in response to emotion and cognitive stress induces perturbations in the heart and the peripheral vasculature that differ in physiology and clinical manifestations when compared with exercise-induced changes. While our conventional framework of epicardial coronary artery disease is foundational in cardiology, an expanded paradigm is required to address the cardiovascular response to mental stress (MS) and its associated risks, thus addressing the intersection of the patient's ecological and psychosocial experience with cardiovascular biology. To advance the field of MS in cardiovascular health, certain core challenges must be addressed. These include differences in the trigger activation between exercise and emotion, identification and interpretation of imaging cues as measures of pathophysiologic changes, characterization of the vascular response, and identification of central and peripheral treatment targets. Sex and psychosocial determinants of health are important in understanding the emerging overlap of MS-induced myocardial ischemia with microvascular dysfunction and symptoms in the absence of obstructive disease. In overcoming these critical knowledge gaps, integration of the field of MS will require implementation studies to guide use of MS testing, to support diagnosis of MS induced cardiac and vascular pathophysiology, to assess prognosis, and understand the role of endotying to direct therapy.

Brain Correlates of Mental Stress-Induced Myocardial Ischemia

OBJECTIVE

Coronary artery disease (CAD) is a major cause of morbidity and mortality, and despite important advances in our understanding of this disorder, the underlying mechanisms remain under investigation. Recently, increased attention has been placed on the role of behavioral factors such as emotional stress on CAD risk. Brain areas involved in memory and the stress response, including medial prefrontal cortex, insula, and parietal cortex, also have outputs to the peripheral cardiovascular system. The purpose of this study was to assess the effects of mental stress on brain and cardiac function in patients with CAD.

METHODS

CAD patients (N = 170) underwent cardiac imaging with [Tc-99m] sestamibi single-photon emission tomography at rest and during a public speaking mental stress task. On another day, they underwent imaging of the brain with [O-15] water positron emission tomography (PET) during mental stress (arithmetic and public speaking) and control conditions.

RESULTS

Patients with mental stress-induced myocardial ischemia showed increased activation with stress in anterior cingulate, inferior frontal gyrus, and parietal cortex (p < .005). This was seen with both arithmetic stress and public speaking stress. Arithmetic stress was additionally associated with left insula activation, and public speaking with right pre/postcentral gyrus and middle temporal gyrus activation (p < .005).

CONCLUSIONS

These findings suggest that mental stress-induced myocardial ischemia is associated with activation in brain areas involved in the stress response and autonomic regulation of the cardiovascular system. Altered brain reactivity to stress could possibly represent a mechanism through which stress leads to increased risk of CAD-related morbidity and mortality.

The Relation of Psychosocial Distress With Myocardial Perfusion and Stress-Induced Myocardial Ischemia

OBJECTIVE

Mental stress-induced myocardial ischemia is a frequent phenomenon in patients with coronary artery disease (CAD). The link between an integrated measure of chronic psychosocial distress and mental stress-induced myocardial ischemia, and whether it differs by sex, has not been examined before.

METHODS

We used latent class analysis to derive a composite measure of psychosocial distress integrating scales of depression, posttraumatic stress, anxiety, anger, hostility, and perceived stress in 665 individuals with stable CAD. Participants underwent myocardial perfusion imaging with mental stress and perfusion defects were quantified at rest (summed rest score), with mental stress (summed stress score), and their difference (summed difference score), the latter being an index of inducible ischemia.

RESULTS

The M (SD) age was 63 (9) years, and 185 (28%) were women. Latent class analysis characterized the study sample into four distinct classes of incremental psychosocial distress. In women, class 4 (highest distress) had an adjusted 4.0-point higher summed rest score (95% confidence interval = 0.2-7.7) as compared with class 1 (lowest distress), whereas no difference was observed in men (-0.87 points, 95% confidence interval = -3.74 to 1.99, p = .04 for interaction). There was no association between the psychosocial distress latent variable and summed difference score in either women or men.

CONCLUSIONS

Among patients with CAD, a higher level of psychosocial distress is not associated with mental stress ischemia, but it is associated with more resting (fixed) perfusion abnormalities in women only, as well as with blunted hemodynamic response to mental stress in both men and women.

Chest Pain and Mental Stress-Induced Myocardial Ischemia: Sex Differences

BACKGROUND

Mental stress-induced myocardial ischemia is a frequent phenomenon in patients with coronary artery disease. Women with coronary artery disease tend to have more mental stress-induced myocardial ischemia and more chest pain/anginal symptoms than men, but whether the association between mental stress-induced myocardial ischemia and angina burden differs in women and men is unknown.

METHODS

This was a cross-sectional study with experimental manipulation of 950 individuals with stable coronary artery disease. Chest pain/angina frequency in the previous 4 weeks was assessed with the Seattle Angina Questionnaire's angina-frequency subscale. Mental stress-induced myocardial ischemia was assessed with myocardial perfusion imaging during mental stress (standardized public speaking task). Presence of mental stress-induced myocardial ischemia was based on expert readers and established criteria. A conventional (exercise or pharmacologic) stress test was used as a control condition.

RESULTS

Overall, 338 individuals (37%) reported angina; 112 (12%) developed mental stress-induced myocardial ischemia, and 256 (29%) developed conventional stress ischemia. Women who reported angina had almost double the probability to develop mental stress-induced myocardial ischemia (19% vs 10%, adjusted prevalence rate ratio, 1.90; 95% confidence interval, 1.04-3.46), whereas there was no such difference in men (11% vs 11%, adjusted prevalence rate ratio, 1.09; 95% confidence interval, 0.66-1.82). No association was found between angina symptoms and conventional stress ischemia for women or men. Results for ischemia as a continuous variable were similar.

CONCLUSIONS

In women, but not in men, anginal symptoms may be a marker of vulnerability toward ischemia induced by psychologic stress. These results highlight the psychosocial origins of angina in women and may have important implications for the management and prognosis of women with angina.

Angina and mental stress-induced myocardial ischemia

OBJECTIVE

Mental stress-induced myocardial ischemia is a common phenomenon in patients with coronary artery disease (CAD) and an emerging prognostic factor. Mental stress ischemia is correlated with ambulatory ischemia. However, whether it is related to angina symptoms during daily life has not been examined.

METHODS

We assessed angina frequency (past month) in 98 post-myocardial infarction (MI) subjects (age 18-60 years) using the Seattle Angina Questionnaire. Patients underwent [(99m)Tc]sestamibi SPECT perfusion imaging at rest, after mental stress, and after exercise/pharmacological stress. Summed scores of perfusion abnormalities were obtained by observer-independent software. A summed difference score (SDS), the difference between stress and rest scores, was used to quantify myocardial ischemia under both stress conditions.

RESULTS

The mean age was 50 years, 50% were female and 60% were non-white. After adjustment for age, sex, smoking, CAD severity, depressive, anger, and anxiety symptoms, each 1-point increase in mental stress-SDS was associated with 1.73-unit increase in the angina frequency score (95% CI: 0.09-3.37) and 17% higher odds of being in a higher angina frequency category (OR: 1.17, 95% CI: 1.00-1.38). Depressive symptoms were associated with 12% higher odds of being in a higher angina frequency category (OR: 1.12, 95% CI: 1.03-1.21). In contrast, exercise/pharmacological stress-induced SDS was not associated with angina frequency.

CONCLUSION

Among young and middle-aged post-MI patients, myocardial ischemia induced by mental stress in the lab, but not by exercise/pharmacological stress, is associated with higher frequency of retrospectively reported angina during the day. Psychosocial stressors related to mental stress ischemia may be important contributory factor to daily angina.

Association between anger and mental stress-induced myocardial ischemia

BACKGROUND

Mental stress-induced myocardial ischemia is associated with adverse prognosis in coronary artery disease patients. Anger is thought to be a trigger of acute coronary syndromes and is associated with increased cardiovascular risk; however, little direct evidence exists for a link between anger and myocardial ischemia.

METHODS

[(99m)Tc]-sestamibi single-photon emission tomography was performed at rest, after mental stress (a social stressor with a speech task) and after exercise/pharmacologic stress. Summed scores of perfusion abnormalities were obtained by observer-independent software. A summed-difference score, the difference between stress and rest scores, was used to quantify myocardial ischemia under both stress conditions. The Spielberger's State-Trait Anger Expression Inventory was used to assess different anger dimensions.

RESULTS

The mean age was 50 years, 50% were female, and 60% were non-white. After adjusting for demographic factors, smoking, coronary artery disease severity, depressive, and anxiety symptoms, each IQR increment in state-anger score was associated with 0.36 U-adjusted increase in ischemia as measured by the summed-difference score (95% CI 0.14-0.59); the corresponding association for trait anger was 0.95 (95% CI 0.21-1.69). Anger expression scales were not associated with ischemia. None of the anger dimensions was related to ischemia during exercise/pharmacologic stress.

CONCLUSION

Anger, both as an emotional state and as a personality trait, is significantly associated with propensity to develop myocardial ischemia during mental stress but not during exercise/pharmacologic stress. Patients with this psychologic profile may be at increased risk for silent ischemia induced by emotional stress, and this may translate into worse prognosis.

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.

Psychological and physiological predictors of angina during exercise-induced ischemia in patients with coronary artery disease

OBJECTIVE

This study compares sensory-biological, cognitive-emotional, and cognitive-interpretational factors in predicting angina on an exercise treadmill test (ETT).

METHODS

A total of 163 patients with ETT-induced ischemia and coronary artery disease in the National Heart, Lung, and Blood Institute Psychophysiological Investigations of Myocardial Ischemia study were given an ETT, during which 79 patients reported angina. We assessed the following as potential predictors of self-reported anginal pain: sensory-biological factors (β-endorphin reactivity, hot pain threshold, and maximal ST-segment depression), cognitive-emotional factors (negative affect and symptom perception), and cognitive-interpretational factors (self-reported history of exercise-induced angina). Models were covariate adjusted with predictors examined individually and as part of component blocks.

RESULTS

Logistic regression revealed that history of angina (odds ratio [OR] = 17.41, 95% confidence interval = 7.16-42.34) and negative affect (OR = 1.65, 95% confidence interval = 1.17-2.34), but not maximal ST-segment depression, hot pain threshold, β-endorphin reactivity, or symptom perception, were significant predictors of angina on the ETT. The sensory-biological block was not significantly predictive of anginal pain (χ(2)block = 5.15, p = .741). However, the cognitive-emotional block (χ(2)block = 11.19, p = .004) and history of angina (cognitive-interpretation; χ(2)block = 54.87, p < .001) were predictive of ETT angina. A model including all variables revealed that only history of angina was predictive of ETT pain (OR = 16.39, p < .001), although negative affect approached significance (OR = 1.45, p = .07).

CONCLUSIONS

In patients with ischemia, cognitive-emotional and cognitive-interpretational factors are important predictors of exercise angina.

Depressive symptoms and mental stress-induced myocardial ischemia in patients with coronary heart disease

OBJECTIVES

The aim of this study was to examine the associations between depressive symptoms and mental stress-induced myocardial ischemia (MSIMI) in patients with coronary heart disease (CHD).

METHODS

Adult patients with documented CHD were recruited for baseline mental stress and exercise stress screening testing as a part of the enrollment process of the Responses of Myocardial Ischemia to Escitalopram Treatment trial. Patients were administered the Beck Depression Inventory II and the Center for Epidemiologic Studies Depression Scale. After a 24-48-hour β-blocker withdrawal, participants completed three mental stress tests followed by a treadmill exercise test. Ischemia was defined as a) any development or worsening of any wall motion abnormality and b) reduction of left ventricular ejection fraction at least 8% by transthoracic echocardiography and/or ischemic ST-segment change by electrocardiography during stress testing. MSIMI was considered present when ischemia occurred in at least one mental test. Data were analyzed using logistic regression adjusting for age, sex, and resting left ventricular ejection fraction.

RESULTS

One hundred twenty-five (44.2%) of 283 patients were found to have MSIMI, and 93 (32.9%) had ESIMI. Unadjusted analysis showed that Beck Depression Inventory II scores were positively associated with the probability of MSIMI (odds ratio = 0.1.30: 95% confidence interval = 1.06-1.60, p = .013) and number of MSIMI-positive tasks (all p < .005). These associations were still significant after adjustment for covariates (p values <.05).

CONCLUSIONS

In patients with CHD, depressive symptoms were associated with a higher probability of MSIMI. These observations may enhance our understanding of the mechanisms contributing to the association of depressive symptoms to future cardiovascular events. Trial Registration Clinicaltrials.gov identifier: NCT00574847.

Emotional triggers in myocardial infarction: do they matter?

Considerable excitement and interest have arisen recently concerning the role that acute emotional triggers may play in precipitating a myocardial infarction (MI). Observational studies have found repeatedly that patients report excessive anger, anxiety, sadness, grief, or acute stress immediately prior to onset of MI, and recent meta-analyses summarizing these findings reported strong associations between MI occurrence and many of these acute emotions. However, it is unclear whether and through what mechanisms acute emotional triggers might influence MI, and whether there is any clinical utility in knowing if or how emotions trigger MI. We debate whether emotional triggers matter by reviewing the recent evidence for the association between acute emotional triggers and MI and by describing the potential pathophysiological characteristics and mechanisms underlying this association and the preventive strategies that could be used to mitigate the risk of acute MI. We also examine whether the study of emotional triggers could influence clinical risk management or changes in clinical practice/management. We offer suggestions for research that might shed light on whether emotional triggers could initiate a paradigm shift in preventive cardiology, or whether acute emotional triggers are either intractable catalysts for, or merely an epiphenomenon of, some MIs.

Symptoms of anxiety and depression are correlates of angina pectoris by recent history and an ischemia-positive treadmill test in patients with documented coronary artery disease in the pimi study

Objective. We tested the association of specific psychological characteristics in patients having stable coronary disease with the reporting of anginal symptoms during daily activities, and positive exercise testing. Methods. One hundred and ninety-six patients with documented CAD enrolled in the Psychophysiological Investigations of Myocardial Ischemia (PIMI) Study completed an anginal history questionnaire and a battery of psychometric tests. They also underwent standardized exercise treadmill tests. Results. Patients with a recent history of angina were more likely to be female, and had higher Beck Depression (P = .002), State Anxiety (P = .001), Trait Anxiety (P = .03), Harm Avoidance (P = .04) and Muscle Tension (P = .004) scores than patients who had no recent history of angina. Along with several treadmill variables indicating more severe disease state and reduced exercise tolerance, patients who developed angina on a positive treadmill test also displayed higher scores on the Beck Depression Inventory (P = .003) and State Anxiety (P = .004) scales. Conclusions. Several psychological characteristics, and most notably anxiety and depression, are strong correlates of recent angina and angina in the presence of ischemia provoked by treadmill testing.

Comparison of myocardial ischemia during intense mental stress using flight simulation in airline pilots with coronary artery disease to that produced with conventional mental and treadmill exercise stress testing

Mental stress increases cardiovascular morbidity and mortality. Although laboratory mental stress often causes less myocardial ischemia than exercise stress (ES), it is unclear whether mental stress is intrinsically different or differences are due to less hemodynamic stress with mental stress. We sought to evaluate the hemodynamic and ischemic response to intense realistic mental stress created by modern flight simulators and compare this response to that of exercise treadmill testing and conventional laboratory mental stress (CMS) testing in pilots with coronary disease. Sixteen airline pilots with angiographically documented coronary disease and documented myocardial ischemia during ES were studied using maximal treadmill ES, CMS, and aviation mental stress (AMS) testing. AMS testing was done in a sophisticated simulator using multiple system failures as stressors. Treadmill ES testing resulted in the highest heart rate, but AMS caused a higher blood pressure response than CMS. Maximal rate-pressure product was not significantly different between ES and AMS (25,646 vs 23,347, p = 0.08), although these were higher than CMS (16,336, p <0.0001). Despite similar hemodynamic stress induced by ES and AMS, AMS resulted in significantly less ST-segment depression and nuclear ischemia than ES. Differences in induction of ischemia by mental stress compared to ES do not appear to be due to the creation of less hemodynamic stress. In conclusion, even with equivalent hemodynamic stress, intense realistic mental stress induced by flight simulators results in significantly less myocardial ischemia than ES as measured by ST-segment depression and nuclear ischemia.

Stress reactivity in patients with workplace hypertension

Aim. To investigate the specific features of stress reactivity and diagnostic potential of psycho-emotional tests for identification of the patients with workplace arterial hypertension (WPAH). Material ad methods. The study included 197 patients with WPAH and 132 subjects with essential AH (EAH). All participants underwent blood pressure monitoring (BPM) during work and leisure hours and stress reactivity assessment (count test). Results. In WPAH and EAH patients, the count test resulted in increased systolic (SBP), diastolic (DBP) BP, and heart rate (HR) (р<0,001), which was an evidence of stress-related functional cardiovascular reaction. In subjects with new-onset WPAH, compared to EAH patients, the SBP and HR increases were greater by 7,9 mm Hg (р<0,005) and 4,3 bpm (р<0,001), respectively. In patients with long-term EAH, SBP increase was greater by 3,4 mm Hg (p=0,03), with a halved HR increase (p<0,001). In healthy controls and AH patients, the differences between baseline levels of SBP and DBP, peak levels during the count test, and BMP levels for work hours were comparable. Conclusion. The patients at early WPAH stages were characterized by increased cardiovascular reaction to acute induced psycho-emotional stress. At the later WPAH stages, BP reactivity was reduced. The cont test could be used as a screening tool in patients with undiagnosed WPAH.

Usefulness of peripheral arterial tonometry in the detection of mental stress-induced myocardial ischemia

BACKGROUND

Mental stress-induced myocardial ischemia (MSIMI) identifies a subset of coronary arterial disease (CAD) patients at increased risk for adverse cardiovascular events. Peripheral arterial vasoconstriction has been consistently reported as an underlying mechanism for ischemia development in this setting and as such affords a unique opportunity for the noninvasive detection of this phenomenon.

HYPOTHESIS

We studied the usefulness of a peripheral arterial tonometry (PAT) technique in the detection of MSIMI. We sought to identify response patterns that would predict the development of MSIMI.

METHODS

Participants were 211 patients with documented CAD. Mental stress testing was performed using a public speaking task. Rest-stress myocardial perfusion imaging was the gold standard for ischemia detection. PAT responses were assessed during the 2 phases of the stressful task (stress anticipation and the task performance) and were calculated as a ratio of stress to the resting pulse wave amplitude.

RESULTS

Vascular response during the stress anticipation period (speech preparation) was more pronounced than during the actual speaking task (the mean preparation index was 0.64 +/- 0.53; the mean speech index was 0.72 +/- 0.60; P < 0.001). PAT response during speech preparation had modest accuracy for predicting MSIMI (area under the curve [AUC] was 0.63; 95% confidence interval [CI]: 0.53-0.74, P = 0.015). A PAT index < or = 0.52 was identified as the best cut off value for detecting MSIMI with a sensitivity of 76% and a specificity of 56%.

CONCLUSION

We identified a pattern of peripheral arterial response to mental stress that has a relatively modest accuracy in predicting MSIMI. Further research is needed to validate the findings of this study.

Stress responses and baroreflex function in coronary disease

Exaggerated pressor responses to mental stress in patients with coronary artery disease (CAD) are associated with increased risk for subsequent cardiovascular events. The integrated baroreflex gain and its mechanical and neural component were estimated and then related to the blood pressure and heart rate responses to simulated real-life stressors: mental arithmetic and public speaking. Eighteen healthy individuals (aged 61 +/- 8 yr) and 29 individuals with documented CAD but no other comorbidities (aged 59 +/- 8 yr) were studied. Heart rate and blood pressures were continuously assessed before, during preparation for, and during performance of a math task and a speech task. The assessment of beat-to-beat carotid diameters during baroreflex engagement was used to estimate the integrated baroreflex gain and its mechanical and neural component. The CAD subjects demonstrated significantly greater increases in heart rate and blood pressures for the performance of the speech task. However, there were no group differences in integrated cardiovagal baroreflex gain or either mechanical or neural baroreflex component. These findings indicate that the augmented pressor responses in CAD do not result from a generalized arterial baroreflex deficit.

Comparison of peripheral arterial response to mental stress in men versus women with coronary artery disease

There are profound gender-related differences in the incidence, presentation, and outcomes of coronary artery disease (CAD). These differences are not entirely explained by traditional cardiovascular risk factors. Nontraditional risk factors, such as psychological traits, have increasingly been recognized as important contributors to the genesis and outcomes of CAD. Mental stress induces significant peripheral arterial vasoconstriction, with consequent increases in heart rate and blood pressure. These changes are thought to underlie the development of myocardial ischemia and other mental stress-induced adverse cardiac events in patients with CAD. This study examined for gender-related differences in peripheral arterial response to mental stress in a cohort of patients with CAD using a novel peripheral arterial tonometric (PAT) technique. There were 211 patients (77 women; 37%) with a documented history of CAD and a mean age of 64 +/- 9 years. Patients were enrolled from August 18, 2004, to February 21, 2007. Mental stress was induced using a public speaking task. Hemodynamic and PAT measurements were recorded during rest and mental stress. The PAT response was calculated as a ratio of pulse wave amplitude during stress to at rest. PAT responses were compared between men and women. The PAT ratio (during stress to at rest) was significantly higher in women compared with men. Mean PAT ratio was 0.80 +/- 0.72 in women compared with 0.59 +/- 0.48 in men (p = 0.032). This finding remained significant after controlling for possible confounding factors (p = 0.037). In conclusion, peripheral vasoconstrictive response to mental stress was more pronounced in men compared with women. This finding may suggest that men have higher susceptibility to mental stress-related adverse effects. Additional studies are needed to determine the significance of this finding.

Effect of bupropion on physiological measures of stress in smokers during nicotine withdrawal

Studies suggest that among cigarette smokers trying to quit, stress undermines abstinence. Little research has assessed if therapies that increase smoking cessation rates impact physiological measures of stress response. Forty-three subjects completed this repeated-measures study in which a laboratory assessment was completed at baseline and after 17 days of treatment with either placebo (n=15), bupropion sustained release (150 mg twice daily) (n=14) or bupropion with stress reduction counseling (n=14). All subjects quit smoking 3 days prior to the second laboratory assessment. At each laboratory assessment physiological measures of stress (i.e. blood pressure, heart rate, plasma epinephrine, norepinephrine and cortisol concentrations) were measured during rest periods and in response to a speech, a math and a cold pressor task. Among subjects taking placebo, physiological measures of stress were generally lower at rest and during the stressors after smoking cessation. In those taking bupropion these measures were equivalent at the two assessments. Additionally, compared to placebo, those on bupropion had a greater diastolic blood pressure response to the speech stressor and greater systolic blood pressure response to the math stressor during the second laboratory session. This study suggests that bupropion may be maintaining physiological measures of stress during the nicotine withdrawal period.

Myocardial perfusion study of panic attacks in patients with coronary artery disease

Panic disorder (PD) and panic-like anxiety have been associated with an increased risk of cardiovascular death. No study has specifically examined the association between panic attacks and ischemia in patients who have coronary artery disease (CAD). We hypothesized that panic attacks would induce myocardial perfusion defects in patients who have CAD and PD. Sixty-five patients who had CAD and positive results with nuclear exercise stress testing (35 with PD and 30 without PD served as controls) underwent a well-established panic challenge test (1 vital capacity inhalation of a gas mixture containing 35% carbon dioxide and 65% oxygen) and were injected with technetium-99m sestamibi at inhalation. Single-photon emission computed tomography was used to assess per-panic challenge perfusion defects, and heart rate, blood pressure, and 12-lead electrocardiogram were continuously measured during the procedure. Patients were not withdrawn from their cardiac medications. Patients who had PD were significantly younger than the controls; otherwise groups did not differ with respect to gender, cardiac medications, nuclear exercise test results, and baseline heart rate and blood pressure. Seventy-four percent of patients (26 of 35) who had PD had a panic attack at inhalation versus 6.7% of controls (2 of 30, p <0.001). As hypothesized, patients who had PD and demonstrated a panic attack were more likely to develop a reversible myocardial perfusion defect than were controls who did not have an attack (80.9% vs 46.4% p = 0.009). Thus, despite being on their cardiac medications, panic attacks preferentially induced significant perfusion defects in patients who had CAD and PD. In conclusion, panic attacks in patients who have CAD appear to be bad for the heart.

Anxiety level and responses to stress caused by air raids among patients with ischemic heart disease

BACKGROUND

This study was undertaken to examine the short-term responses of patients with ischemic heart disease to life-threatening events such as war.

METHODS

This retrospective study included 75 persons with ischemic heart disease who were admitted to the Cardiac policlinic for a control check-up immediately after the suspension of air raids. Two-thirds of them were male (average age 62 +/- 10). Data were obtained using a specially conceived questionnaire based on recall.

RESULTS

Almost 40% of patients estimated that they were very anxious the week before the attacks began, but the anxiety decreased after the beginning of the air raids. Frequency of anginal pains increased after the start of the air raids, but the difference was not statisticaly significant. The intensity of pains drastically increased in the first week of war. Consequently, the average number of pain killers consumed increased from the week before the attacks to the first week of the attacks, and it reached the highest value the week after the suspension of the attacks (1.39, 1.87, and 3.02 pain pills per week, respectively). The average weekly number of medications was 3.50 in the week prior to the air raids, increased to 5.05 during the first week of air raids, and rose to 6.06 in the week after the suspension.

CONCLUSION

The adjustment on the psychological level was rapid but physical symptoms increased. This implies that physical adaptation to stress could be slower, or that the stress of the war provoked permanent changes in physical status.

The effect of mental stress on the non-dipolar components of the T wave: modulation by hypnosis

OBJECTIVE

Mental or emotional stress-induced ventricular arrhythmias and sudden cardiac death are thought to be mediated by the autonomic nervous system and ischemia. In the absence of ischemia, increased inhomogeneity of repolarization is thought to be important. We tested the hypotheses that in the absence of ischemia, mental stress may modulate repolarization by changing autonomic balance; and mental relaxation induced by hypnosis may offset the potentially adverse effects of stress on the cardiac electrophysiology.

METHODS

Twelve healthy volunteers (6 male, age 18-35, mean 25 years) experienced a series of different emotions intended to induce a wide range of autonomic response (42 test epochs) on two separate occasions, with and without hypnosis, with continuous electrocardiogram recording. Low- (LF) and HF (high-frequency) heart rate variability was measured and ventricular repolarization was assessed using the relative T-wave residua (proportion of nondipolar components of the T wave) calculated for the T-onset - T peak (TWR-peak T), T peak -T end (TWR-end T), and the whole T wave (TWR).

RESULTS

Emotionally induced changes in LF and LF/HF ratio correlated with changes in TWR, e.g., (R = 0.51, p < .001; R = 0.59, p < .0001; and R = 0.59, p < .0003, for LF/HF versus TWR, TWR-Peak T, and TWR-end T, respectively. Mental relaxation induced by hypnosis increased LF power (1,205 ms2) versus 624 ms2, p < .003 for hypnotized versus nonhypnotized state), HF power (1,619 ms2 versus 572 ms2), p < .0004), and reduced LF/HF ratio (1.0 versus 1.5, p = .052) and was associated with a marked reduction in the changes in repolarization in response to emotion, e.g., 10.7 x 10(-6) versus 5.0 x10(-6), p < .03 for TWR.

CONCLUSIONS

a) Mental stress in the absence of ischemia altered repolarization inhomogeneity via change in the autonomic balance. b) Mental relaxation induced by hypnosis greatly reduced the effect of mental stress on repolarization. c) These findings may have implications for arrhythmogenesis.

Cardiovascular reactivity and adaptation to recurrent psychological stress: Replication and extension

We analyzed the effects of evaluative observation and baseline duration on cardiovascular reactivity and adaptation to recurrent psychological stress. Cardiovascular reactivity to mental arithmetic stress was assessed in college men and women (N=224) during two pretest tasks, a test task, and a posttest task. Participants were assigned randomly in a 2 x 2 design to manipulations of baseline duration before the test task (4 min vs. 12 min) and evaluative observation during the test task (observed vs. control). Repeated exposure to stress attenuated cardiac but not vascular reactivity. Evaluative observation disrupted cardiac adaptation, resulting in a resurgence of beta-adrenergic cardiac reactivity during the test task. Cardiac adaptation resumed fully during the posttest task. Baseline duration had no effect on reactivity. The results replicate and extend previous work, and support the dual process theory of habituation and sensitization.

Religiosity and the expansion of caregiver stress

We present a stress process framework as a model for understanding how religiosity may influence the expansion of stress. Survey data from informal caregivers to a spouse with Alzheimer's disease or a related dementia (n = 200) were analyzed to observe the relationships among three variables: (1) care-related stress, (2) religiosity, and (3) depression. This sample, which has a mean age of 73 years, demonstrates high rates of self-described religiosity, church attendance and frequency of prayer. Using these criteria, women and racial/ethnic minority caregivers are the most religious. In a series of multivariate analyses, we found strong evidence to suggest that there is an expansion of care-related stressors leading to depression in this sample. Religiosity, as measured here, appears to be largely unrelated to stress and stress expansion. We found no evidence to suggest that it moderates stress expansion. However, these data do suggest that one stressor--feelings of role overload--is correlated with greater levels of self-perceived religiosity, which among caregivers who have health problems of their own is associated with greater depressive symptomatology. Thus, for a sub-sample of these caregivers, we find weak evidence of a mediation effect wherein one subjective, non-organizational dimension of religiosity is a conduit of the harmful effects of stress (rather than a suppressor). Results and data limitations are discussed in relation to better assessing the role of religiosity and spirituality in the experience of the stress process.

Psychosocial influences on the development and course of coronary heart disease: current status and implications for research and practice

Psychosocial characteristics predict the development and course of coronary heart disease (CHD). In this review, the authors discussed human and animal research on psychophysiological mechanisms influencing coronary artery disease and its progression to CHD. They then reviewed literature on personality and characteristics of the social environment as risk factors for CHD. Hostility confers increased risk, and a group of risk factors involving depression and anxiety may be especially important following myocardial infarction. Social isolation, interpersonal conflict, and job stress confer increased risk. Psychosocial interventions may have beneficial effects on CHD morbidity and mortality, although inconsistent results and a variety of methodological limitations preclude firm conclusions. Finally, they discussed implications for clinical care and the agenda for future research.

Impact of daily life myocardial ischemia in patients with chronic reversible and irreversible myocardial dysfunction

Repetitive myocardial ischemia during daily life has been suggested as the underlying mechanism of reversible myocardial dysfunction, which may progress into a hibernating state. Thirty-seven patients with ischemic cardiomyopathy (ejection fraction 35 +/- 7%) underwent positron emission tomography (N-13 ammonia and 18-F-fluoro-2-deoxy-glucose [FDG]) and exercise testing before coronary artery bypass grafting (CABG) and 48- hour ambulatory electrocardiographic monitoring to detect ischemia before CABG and 6 months postoperatively. Reversibility of regional myocardial dysfunction was detected by echocardiographic follow-up at 5 days, 2 months, and 6 months after the operation. Preoperatively, ischemic episodes during daily activities were more common (2 [25th to 75th percentiles 0 to 4] vs 0 episodes, p <0.01) and duration of ischemia longer (9 [25th to 75th percentiles 0 to 37] vs 0 [25th to 75th percentiles 0 to 1] minutes, p <0.02) in patients with reversible dysfunction (n = 15) than in patients with irreversible dysfunction (n = 22). The number of ischemic episodes per patient correlated with the numbers of reversibly dysfunctional segments (p = 0.003), viable segments as seen by positron emission tomography (p <0.05), and flow-metabolic mismatch segments (p <0.05). CABG eliminated ambulatory ischemic episodes in patients with reversible dysfunction (0 episodes, p <0.05 vs before CABG). Preoperatively, all patients with reversible dysfunction had a positive exercise test (14 of 15 patients), whereas daily life ischemia was present in 60% of patients. Reversibly dysfunctional segments in patients with ambulatory ischemia had faster recovery of function (15 of 28 patients vs 2 of 12 patients recovered at 5 days, p <0.05), higher FDG uptake (0.86 +/- 0.19% vs 0.71 +/- 0.24%, p <0.05) than in patients without ambulatory ischemia, whereas perfusion was similar (0.63 +/- 0.20 and 0.62 +/- 0.19 ml/g/min). Thus, exercise-induced myocardial ischemia is associated with reversibility of myocardial dysfunction, but not all patients with reversible ischemic cardiomyopathy have ischemic attacks during daily life.

Efficacy of heparin-coated stent in early setting of acute myocardial infarction

Primary stenting has been reported to be superior to balloon percutaneous transluminal coronary angioplasty (PTCA) in acute myocardial infarction (AMI) for recurrent ischemia, target lesion revascularization, and restenosis. However, concerns about early reocclusion or thrombosis after stenting in the very thrombotic environment of acute myocardial infarction still remain. Therefore, postprocedural short-term heparin or GpII(b)/III(a) receptor blockades has been used. The aim of our study was to evaluate the safety, feasibility, and long-term efficacy of heparin-coated stent in the early setting of AMI without postprocedural heparin or GpII(b)/III(a) receptor blockade infusion. We studied 102 consecutive patients presenting to cardiac catheterization laboratory < or = 6 hr from the onset of chest pain. No patients who were implanted with heparin-coated stents received heparin or GpII(b)/III(a) receptor blockade infusion after the procedures, not even patients who showed an angiographically large thrombus burden before stenting. Patients were evaluated for clinical endpoints at 30 days and 6 months. Coronary angiography was required for all patients at 2 weeks and 6 months after the procedure. Angiographic and procedural successes were 100% and 98%, respectively. Two patients (2%) died of heart failure without evidence of reocclusion of stented vessel during the hospitalization and 4 (4%) additional patients died of refractory heart failure within the first 6 months. Major bleeding complication occurred in one patient (1%). Recurrent myocardial infarction developed in one patient at 4 months. Early angiographic follow up at 2 weeks was performed in 88% of all patients, none of whom showed thrombotic stent occlusion. Six-month angiographic follow-up was completed in 71%(64/91) of eligible patients and binary restenosis was present in 17.2% of stented vessels. Eight(8%) patients underwent repeat PTCA. Cardiac event-free survival rate at 6 months was 86.3%. This study demonstrates that heparin-coated stents are safe in the early setting of acute myocardial infarction and no additional heparin infusion after stenting is necessary, which may reduce bleeding complications. Angiographic restenosis rate compares favorably to the binary restenosis rate from other studies with uncoated stents.

Effect of low-dose estrogen on hemodynamic response to stress

OBJECTIVE

To determine the effect of low-dose esterified estrogen on hemodynamic responses at rest and during stress in postmenopausal women, and to compare the changes with those seen with conjugated equine estrogen.

DESIGN

Open-label study of esterified estrogen compared with a double-blind, placebo-controlled investigation of conjugated equine estrogen.

SETTING

Healthy volunteers in an academic research environment.

PATIENT(S)

Postmenopausal women with normal endometrium, not currently using hormones.

INTERVENTION(S)

Cardiovascular parameters at rest and in response to stressors were assessed in 11 postmenopausal women before and 6 months after receiving 0.3 mg esterified estrogen. Responses were compared with 42 postmenopausal women randomized to 0.625 mg conjugated equine estrogen or placebo.

MAIN OUTCOME MEASURE(S)

Changes in mean arterial pressure (MAP) and vascular resistance index from before to after treatment.

RESULT(S)

At rest, MAP increased 3.3 +/- 1.5 mm Hg (+/-SD) in the placebo group, while declining 2.3 +/- 1.5 mm Hg and 4.8 +/- 1.4 mm Hg, respectively, in the esterified estrogen and conjugated equine estrogen groups after treatment. During mental stressors, MAP dropped significantly in both treatment groups. At rest and during mental stressors, vascular resistance index decreased with estrogen treatment.

CONCLUSION(S)

Low-dose esterified estrogen improved hemodynamic patterns similar to standard doses of conjugated equine estrogen in postmenopausal women.

Primary stenting in nonselected patients with acute myocardial infarction: the Multilink Duet in Acute Myocardial Infarction (MIAMI) trial

Most randomized trials comparing primary stenting with primary coronary angioplasty (PTCA) excluded patients at high risk from enrollment, thus arising the important question about the generalizability of the randomized trial results to all patients with AMI. The aim of this study was to assess the feasibility and effectiveness of a primary infarct-related artery (IRA) stenting strategy using a second-generation tubular stent in nonselected patients with acute myocardial infarction (AMI). All patients with AMI were considered eligible for primary IRA stenting. No restriction was made based on age or clinical status on presentation, or coronary anatomy, except in cases of a reference IRA diameter < 2.5 mm. The primary endpoint of the study was clinical target vessel failure defined as death, reinfarction, or repeat TVR due to restenosis or reocclusion of the IRA. Between June 1998 and March 1999, 201 consecutive patients with AMI underwent mechanical recanalization of the IRA. The mean age was 64 +/- 12, and 16% of patients were aged 75 years or over. The incidence of shock was 9%. Primary IRA stenting was performed in 89% of the patients. Patients who underwent PTCA alone had a smaller IRA diameter as compared to patients with a stented IRA (2.48 +/- 0.46 mm vs. 3.15 +/- 0.37 mm; P < 0.001). There were no stent deployment failures. The 6-month primary endpoint rate was 15% (2 deaths, 27 repeat TVR, 0 reinfarctions), while the 6-month angiographic restenosis rate was 22%. Primary IRA stenting in nonselected patients with AMI is highly feasible and associated with favorable clinical and angiographic outcomes. Cathet. Cardiovasc. Intervent. 51:273-279, 2000.

Primary angioplasty for acute myocardial infarction in the elderly

Elderly patients with acute myocardial infarction present a formidable therapeutic challenge. Although there appears to be a survival benefit from thrombolytic therapy for the eligible elderly patient, persistent concerns regarding the risk of intracranial hemorrhage impedes utilization in this age group. Primary or direct angioplasty of the infarct artery has been proven to be an effective modality for reperfusion. Randomized comparisons suggest an advantage over thrombolysis in terms of achieving superior patency and mitigating recurrent ischemic events. Primary angioplasty expands the reperfusion population by including many patients ineligible for thrombolysis and is more effective for treating patients at high risk, such as those with cardiogenic shock. Acute angiography accumulates important prognostic and decision-facilitating information. The benefits of primary angioplasty are more impressive for the aging patient. The survival gain and reduction in intracranial hemorrhage may combine to magnify the advantages of performing angioplasty on patients in this group. Emerging evidence concerning the aging population validates continued examination of this invasive reperfusion approach.

ECG Changes, Emotional Arousal, and Subjective State

Abstract Laboratory studies with CHD patients suggest an adverse influence of emotional/mental arousal on myocardial ischaemia or ventricular premature contractions (VPCs). However, it is controversial whether such studies can be generalized to everyday life. In addition, existing ambulatory monitoring studies have shortcomings because emotional arousal is entirely based on subjective reports. The hypothesis of the present study is that during ischaemic episodes or VPCs “objective emotional/mental arousal” will be more pronounced than during comparable episodes without these events. Objective emotional/mental arousal was indicated by a special ambulatory monitoring method which was based on the online analysis of heart rate and physical activity, resulting in the so-called emotional or non-metabolic heart rate. Moreover, the method allowed for ratings of anginal pain. In 223 CHD patients the associations between ischaemia, VPCs, objective emotional/mental arousal, and anginal pain were investigated. Forty-nine patients revealed ischaemic episodes and 115 patients VPCs. Emotional/mental arousal was higher during ischaemic episodes as compared to control minutes whereas minutes with VPCs showed no difference. No differences between ischaemic episodes or VPCs and the respective control minutes were observed for anginal pain. Objective emotional/mental arousal was associated in this study with ischaemia but not with arrhythmia, thus partly confirming the hypothesis stated. Because anginal pain was not related to objective cardiac events, detection of CHD has to rely on medical examinations.

Prognostic value of mental stress testing in coronary artery disease

This study assesses the prognostic value of mental stress-induced ischemic left ventricular wall motion abnormalities and hemodynamic responses in patients with stable coronary artery disease (CAD). Seventy-nine patients (76 men and 3 women) with prior positive exercise test results were exposed to mental arithmetic and a simulated public speech stress in 2 prior studies. Ischemic wall motion abnormalities were monitored using echocardiography or radionuclide ventriculography (RNV). During mental stress testing, new or worsened ischemic wall motion abnormalities to mental stress and exercise were ascertained, as were peak changes in blood pressure and heart rate to mental stress. The occurrence of subsequent cardiac events (including cardiac death, nonfatal myocardial infarction, or revascularization procedures) was ascertained. New cardiac events were observed in 28 of 79 patients (35%) after a median follow-up duration of 3.5 years (range 2.7 to 7.3). Survival analysis indicated that 20 of 45 patients with mental stress ischemia (44%) experienced new cardiac events more frequently than those without mental stress ischemia (8 of 34; 23%; p = 0.048). Type of cardiac event did not differ between mental stress-positive and stress-negative patients. After controlling for baseline blood pressure and study group status (echocardiography vs RNV), there was a significantly higher relative risk of subsequent events for patients with high versus low peak stress-induced diastolic blood pressure responses (RR = 2.4, confidence interval 1.1 to 5.2; p = 0.03). These results demonstrate that ischemic and hemodynamic measures obtained from mental stress testing may be useful in assessing prognosis in CAD patients with prior positive exercise test results.