Prognostic value of mental stress testing in coronary artery disease

The effect of acute psychological stress on QT dispersion in patients with coronary artery disease

BACKGROUND

An acute psychological stress can precipitate ventricular arrhythmias and sudden cardiac death in patients with coronary artery disease (CAD). However, the physiologic mechanisms by which these effects occur are not entirely clear. Mental stress-induced myocardial ischemia occurs in a significant percentage of the CAD population. It is unknown if the proarrhythmic effects of psychological stress are mediated through the development of myocardial ischemia.

OBJECTIVES

To examine the effects of psychological stress on QT dispersion (QTd) among CAD patients and whether these effects are mediated via the development of myocardial ischemia.

METHODS

Psychological stress was induced using a public speaking task. Twelve-lead electrocardiograms (ECG) were recorded at rest, during mental stress, and during recovery. QTd was calculated as the difference between the longest and the shortest QT interval in the 12-lead ECG. Rest-stress myocardial perfusion imaging was also performed to detect mental stress-induced myocardial ischemia.

RESULTS

Mental stress induced a significant increase in QTd compared to the resting condition (P < 0.001). This effect persisted beyond the first 10 minutes of recovery (P < 0.001). QTd was significantly associated with the development of mental stress ischemia with ischemic patients having significantly higher QTd during mental stress than nonischemic patients (P = 0.006). This finding remained significant after controlling for possible confounding factors (P = 0.01).

CONCLUSION

An acute psychological stress induces a significant increase in QTd, which persists for more than 10 minutes after the cessation of the stressor. This effect seems to be, at least partially, mediated by the development of mental stress-induced myocardial ischemia.

A review of neuroimaging studies of stressor-evoked blood pressure reactivity: emerging evidence for a brain-body pathway to coronary heart disease risk

An individual's tendency to show exaggerated or otherwise dysregulated cardiovascular reactions to acute stressors has long been associated with increased risk for clinical and preclinical endpoints of coronary heart disease (CHD). However, the 'brain-body' pathways that link stressor-evoked cardiovascular reactions to CHD risk remain uncertain. This review summarizes emerging neuroimaging research indicating that individual differences in stressor-evoked blood pressure reactivity (a particular form of cardiovascular reactivity) are associated with activation patterns in corticolimbic brain areas that are jointly involved in processing stressors and regulating the cardiovascular system. As supported empirically by activation likelihood estimates derived from a meta-analysis, these corticolimbic areas include divisions of the cingulate cortex, insula, and amygdala--as well as networked cortical and subcortical areas involved in mobilizing hemodynamic and metabolic support for stress-related behavioral responding. Contextually, the research reviewed here illustrates how behavioral medicine and health neuroscience methods can be integrated to help characterize the 'brain-body' pathways that mechanistically link stressful experiences with CHD risk.

Heightened resting neural activity predicts exaggerated stressor-evoked blood pressure reactivity

Individuals who express relatively large-magnitude or "exaggerated" blood pressure (BP) reactions to behavioral stressors are presumably at increased risk for cardiovascular disease. As shown by recent neuroimaging studies, individuals who express exaggerated stressor-evoked BP reactivity also express heightened neural activity in corticolimbic brain areas that centrally regulate the cardiovascular system. These studies, however, have exclusively examined BP reactivity and concomitant neural activity during stressor exposure. If exaggerated BP reactivity originates in part from a centrally regulated and dispositional cardiovascular response tendency, then heightened resting (prestressor) corticolimbic activity may predict the subsequent expression of exaggerated stressor-evoked BP reactivity. To test this hypothesis, perfusion MRI was used to quantify resting regional cerebral blood flow (an indirect metabolic measure of neural activity) in men (n=19) and women (n=20) aged 20 to 37 years who subsequently performed cognitive stressor tasks to evoke BP reactivity. Individuals who expressed larger task-induced rises in systolic and diastolic BP also expressed higher resting regional cerebral blood flow in 4 functionally related corticolimbic areas: the dorsal and perigenual anterior cingulate, medial prefrontal, and insular cortices. Specifically, resting regional cerebral blood flow in these areas accounted, respectively, for 40% and 31% of the variance in systolic (P=0.001) and diastolic (P=0.008) BP reactivity, after accounting for total resting cerebral blood flow, resting BP, task performance, and task-related ratings of unpleasantness, arousal, and perceived psychological control. Heightened resting corticolimbic activity may represent a neurobiological correlate of an individual's predisposition for exaggerated stressor-evoked BP reactivity and possibly related cardiovascular risk.

Noninvasive detection of risk for emotion-provoked myocardial ischemia

OBJECTIVES

To test an easily administered, noninvasive technology to identify vulnerability to mental stress ischemia.

BACKGROUND

Myocardial ischemia provoked by emotional stress (MSI) in patients with stable coronary artery disease (CAD) predicts major adverse cardiac events. A clinically useful tool to risk stratify patients on this factor is not available.

METHODS

Patients with documented CAD (n = 68) underwent single photon emission CT myocardial perfusion imaging concurrent with pulse wave amplitude assessment by peripheral arterial tonometry (PAT) during a mental stress protocol of sequential rest and anger stress periods. Heart rate and blood pressure were assessed, and blood was drawn for catecholamine assay, during rest and stress. MSI was defined by the presence of a new perfusion defect during anger stress (n = 26) and the ratio of stress to rest PAT response was calculated.

RESULTS

Patients with MSI had a significantly lower PAT ratio than those without MSI (0.76 +/- 0.04 versus 0.91 +/- 0.05, p = .03). An ROC curve for optimum sensitivity/specificity of PAT ratio as an index of MSI produced a sensitivity of 0.62 and a specificity of 0.63. Among patients taking angiotensin converting enzyme (ACE) inhibitors, the sensitivity and specificity of the test increased to 0.86 and 0.73, respectively; 90% of patients without MSI were correctly identified.

CONCLUSIONS

PAT in concert with ACE inhibition may provide a useful approach to assess risk for MSI. Future studies should help determine how best to utilize this approach for risk assessment in the clinical setting.

The role of n-3 PUFAs in preventing the arrhythmic risk in patients with idiopathic dilated cardiomyopathy

BACKGROUND

N-3 polyunsaturated fatty acids (n-3 PUFAs) intake is associated with a reduction in sudden cardiac death in patients with ischemic heart disease. Their effects in patients with heart failure caused by idiopathic dilated cardiomyopathy (IDC) are unknown.

METHODS

We compared with placebo the effects of n-3 PUFAs administration in 44 patients with IDC and with frequent or repetitive ventricular arrhythmias at Holter monitoring using a randomized, double-blind design. Arrhythmic risk was assessed by microvolt T-wave analysis (MTWA), signal averaged ECG (SAECG), Holter monitoring, power spectral analysis of heart rate (HR) variability, catecholamine and cytokine plasma levels, at baseline and after 6 months.

RESULTS

At MTWA, 7/12 patients (58%) initially positive became negative after n-3 PUFAs while one patient became positive after placebo (p = 0.019). N-3 PUFAs administration was also associated to normalization of SAECG (11/15 patients, p < 0.0015), decrease in non-sustained ventricular tachycardia (NSVT) episodes (p = 0.0002) and NSVT HR (p = 0.0003), improvement in HR variability and decrease in catecholamine and cytokine plasma levels. The ratio of plasma n-6 PUFAs to n-3 PUFAs decreased from 12.01 to 3.48 after n-3 PUFAs.

CONCLUSIONS

N-3 PUFAs administration is associated with favorable effects on parameters related to arrhythmic risk in patients with idiopathic dilated cardiomyopathy. These results are consistent with antiarrhythmic activity independent from their antiischemic effects.

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.

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

BACKGROUND

Mental stress precipitates myocardial ischemia in a significant percentage of coronary artery disease (CAD) patients. Exercise or adenosine stresses produce different physiologic responses and cause myocardial ischemia via different mechanisms. Little is known about the comparative severity and location of myocardial ischemia provoked by these different stressors. In this study we sought to compare the within-individual ischemic responses to mental versus exercise or adenosine stress in a cohort of CAD patients.

METHODS AND RESULTS

All patients underwent mental stress and either exercise or adenosine testing within a 1-week period. Mental stress was induced via a public speaking task. Rest-stress myocardial perfusion imaging was used with all testing protocols. Participants were 187 patients (65 women [35%]) with a documented history of CAD and a mean age of 64 +/- 9 years. Mental stress-induced myocardial ischemia (MSIMI) was less prevalent and frequently of less magnitude than exercise- or adenosine-induced ischemia. Ischemia induced by exercise or adenosine testing did not accurately predict the development or the location of MSIMI. The overall concordance between these stressors for provoking ischemia was weak (percent agreement, 71%; kappa [+/- SE], 0.26 +/- 0.07). In a minority of patients (11%) mental stress provoked ischemia in the absence of exercise- or adenosine-induced ischemia. Moreover, in patients who had myocardial ischemia during both stressors, there were significant within-individual differences in the coronary artery distribution of the ischemic regions. MSIMI was more likely to occur in a single-vessel distribution (86%) compared with exercise- or adenosine-induced ischemia (54%). The stressors had moderate agreement if the ischemic region was in the right coronary artery territory (percent agreement, 76%; kappa, 0.52 +/- 0.19) or the left anterior descending coronary artery (percent agreement, 76%; kappa, 0.51 +/- 0.19) and significantly lower agreement in the left circumflex territory (percent agreement, 62%; kappa, 0.22 +/- 0.18).

CONCLUSIONS

Our findings indicate that mental and exercise or adenosine stresses provoke different myocardial ischemic responses. These observations suggest that exercise or adenosine testing may not adequately assess the likelihood of occurrence or severity of MSIMI and that different mechanisms are operative in each condition.

Psychobiology of depression/distress in congestive heart failure

Heart failure affects millions of Americans and new diagnosis rates are expected to almost triple over the next 30 years as our population ages. Affective disorders including clinical depression and anxiety are common in patients with congestive heart failure. Furthermore, the presence of these disorders significantly impacts quality of life, medical outcomes, and healthcare service utilization. In recent years, the literature has attempted to describe potential pathophysiologic mechanisms relating affective disorders and psychosocial stress to heart failure. Several potential mechanisms have been proposed including autonomic nervous system dysfunction, inflammation, cardiac arrhythmias, and altered platelet function. These mechanisms are reviewed in this article. Additional novel mechanisms such as mental stress-induced myocardial ischemia are also discussed.

Do men and women differ on measures of mental stress-induced ischemia?

OBJECTIVE

To consider the effects of gender on ischemia in a larger sample, with broadly defined coronary artery disease (CAD). Mental stress has been shown to cause transient myocardial ischemia in a significant percentage of people with CAD. However, little is known about the effects of mental stress on ischemic processes in women. Most studies to date either had few women or required a positive exercise stress test.

METHODS

Participants (61 women, 93 men; average age = 63 years) had documented CAD (positive stress test, abnormal catheterization even with minimal disease, or previous myocardial infarction). They underwent mental stress testing and radionuclide perfusion imaging (stress/ rest). Cardiac function data were collected and stress was compared with baseline. The data were then submitted to a series of analyses of variance.

RESULTS

A total of 50 (32%) participants exhibited reversible ischemia post psychological stress. This reflects a relative rate of 33% (n = 31 of 93) for men and 31% (n = 19 of 61) for women. No difference between men and women were observed on any measure of hemodynamic functioning (blood pressure, heart rate, or cardiac perfusion).

CONCLUSIONS

Results of this study showed no significant differences between men and women on measures of hemodynamic functioning or cardiac perfusion.

Social support predicts hemodynamic recovery from mental stress in patients with implanted defibrillators

OBJECTIVE

Emotionally stressful events appear to trigger malignant ventricular arrhythmias and myocardial infarction in cardiac patients. However, the physiological pathways linking psychological stress to arrhythmias and adverse disease outcomes remain incompletely understood. In patients with implanted cardioverter-defibrillators (ICD) we investigated the impact of emotions and social support on cardiovascular recovery from mental stress. The hypothesis tested was that psychosocial resources help to maintain adaptive hemodynamic responses to mental stress.

METHODS

In 55 ICD patients we noninvasively measured hemodynamic and autonomic parameters during two sequentially performed mental stress tests (arithmetic and anger recall tests). The cardiovascular data obtained were associated with results from well-validated psychometric self-rating tests for anxiety and depression (HADS), anger (STAXI), and perceived social support (FSozU).

RESULTS

In the rest period after mental stress application the majority of the study participants (82%) showed a rapid fall in cardiac index, arterial blood pressure, and heart rate, as well as an increase in high-frequency heart rate variability, while the remainder had no or unexpected changes in the hemodynamic parameters examined. Patients missing hemodynamic recovery in the post-stress phase reported significantly less social support than normally reacting patients (P<.05). Multivariate logistic regression models confirm that social support is an independent and significant predictor of preserved hemodynamic recovery from mental stress, even after controlling for somatic confounders (multivariate odds ratio 4.1; 95% confidence interval 1.3-12.7; P=.015).

CONCLUSIONS

Our data indicate that in ICD patients better perceived social support is associated with a more pronounced hemodynamic recovery after mental stress.

Dehydration does not influence cardiovascular reactivity to behavioural stress in young healthy humans

Enhanced hydration increases the human cardiovascular reactivity to mental stress. If reduced water intake has the opposite effect, this would suggest controlling for water deprivation when studying such responses. Blood pressure, heart rate and parasympathetically dominated beat-to-beat heart rate fluctuations were assessed during resting baseline and mental stress. Two challenging cognitive-motor tasks, a 5-Choice Reaction Time Task (CRTT) and a Paced Auditory Serial Addition Task (PASAT), served as mental stress tests. Eight female and eight male volunteers were examined twice, after 24 h of water deprivation and after normal water intake (counterbalanced order, 7-day interval). Water deprivation resulted in moderate dehydration with a mean 2.6% decrease of total body weight. Dehydration did neither affect baseline blood pressure, heart rate, nor blood pressure reactivity to mental stress. However, dehydration slightly (-1.2 bpm) diminished heart rate reactivity to the PASAT (P = 0.03) and increased beat-to-beat heart rate fluctuations in response to the CRTT (P = 0.05). Dehydration intensified CRTT- and PASAT-induced reductions of beat-to-beat heart rate fluctuations in females (gender x dehydration interactions: P = 0.04-0.05). Moderate dehydration induced by water restriction has no effect on blood pressure reactivity to mental stress. The effects on heart rate reactivity are small. However, stress-induced parasympathetic withdrawal may be fortified during dehydration in females, which suggests controlling for water intake when studying such responses.

Coronary artery disease and depression: patients with more depressive symptoms have lower cardiovascular reactivity during laboratory-induced mental stress

OBJECTIVE

To investigate the relationship between symptoms of depression and cardiovascular reactivity during mental stress in patients with coronary artery disease (CAD). Depressive symptoms are common in patients with CAD and are related to an increased risk of cardiac events and death. Some researchers have proposed that negative outcomes in depressed patients with CAD may be related to exaggerated cardiovascular reactivity and psychological stress. However, the data are unclear.

METHODS

Patients with CAD (n = 128; mean age = 64 years) were recruited for this study. Participants underwent psychological stress testing and 2-day (stress/rest) radionuclide imaging. The Beck Depression Inventory (BDI) results were collected at baseline. Cardiac function data were also gathered and stress data were compared with baseline findings.

RESULTS

The change in systolic blood pressure (SBP) from rest to stress was 47 +/- 18 (mean +/- standard deviation) mm Hg, diastolic blood pressure (DBP) = 30 +/- 11 mm Hg, double product difference (DP) = 5887 +/- 3095, and heart rate (HR) = 20 +/- 13 beats/minute (p < .001 for all). The BDI score was 8.7 +/- 5.6. The BDI score was negatively correlated with all hemodynamic variables, although only significant with stress SBP and DP, and HR and DP changes. BDI scores also predicted changes in HR and DP. HR remained significant in regression analyses controlling for other sample characteristics.

CONCLUSIONS

This study showed a negative relationship between depressive symptoms and cardiovascular reactivity to mental stress. In contrast to the mechanism proposed by earlier researchers, this study suggests that decreased cardiovascular reactivity occurs with increased depressive symptomology. The mechanism by which this effect occurs and its clinical significance are still unknown.

C-reactive protein and vulnerability to mental stress-induced myocardial ischemia

Myocardial ischemia provoked in the laboratory during mental stress (MSI) in patients with stable coronary artery disease (CAD) predicts subsequent clinical events. The pathophysiology of MSI differs from that of exercise ischemia, and the mechanisms tying MSI to poor prognosis are not known. C-reactive protein (CRP) is a risk marker for cardiovascular events in patients with CAD, but little is known regarding the relationship of CRP to MSI. The purpose of this study was to examine the association of CRP to risk of MSI in CAD patients. Eighty-three patients with stable CAD underwent simultaneous single-photon emission computed tomography (SPECT) imaging with technetium-99m tetrofosmin myocardial perfusion imaging (MPI) and transthoracic echocardiography (TTE), at rest and during MS induced by laboratory mental stress. Serum CRP levels were measured 24 h after MS. MSI was defined by the presence of a new perfusion defect on SPECT and/or new regional wall motion abnormality on TTE during MS. Of the 83 patients, 30 (36%) developed MSI. There was no difference in gender, sex, BMI, histories of diabetes, hypertension, smoking, lipid profile, medications used (including statins, beta-blockers, ACE inhibitors, and aspirin), or hemodynamic response during MS between those with and without MSI. In univariate logistic regression analysis, each unit (1 mg/L) increase in CRP level was associated with 20% higher risk of MSI (OR 1.2, 95% CI 1.01-1.39, P=.04). This relationship remained in multivariate models. These data suggest that levels of CRP may be a risk marker for MSI in patients with CAD.

C-reactive protein and vulnerability to mental stress-induced myocardial ischemia

Myocardial ischemia provoked in the laboratory during mental stress (MSI) in patients with stable coronary artery disease (CAD) predicts subsequent clinical events. The pathophysiology of MSI differs from that of exercise ischemia, and the mechanisms tying MSI to poor prognosis are not known. C-reactive protein (CRP) is a risk marker for cardiovascular events in patients with CAD, but little is known regarding the relationship of CRP to MSI. The purpose of this study was to examine the association of CRP to risk of MSI in CAD patients. Eighty-three patients with stable CAD underwent simultaneous single-photon emission computed tomography (SPECT) imaging with technetium-99m tetrofosmin myocardial perfusion imaging (MPI) and transthoracic echocardiography (TTE), at rest and during MS induced by laboratory mental stress. Serum CRP levels were measured 24 h after MS. MSI was defined by the presence of a new perfusion defect on SPECT and/or new regional wall motion abnormality on TTE during MS. Of the 83 patients, 30 (36%) developed MSI. There was no difference in gender, sex, BMI, histories of diabetes, hypertension, smoking, lipid profile, medications used (including statins, beta-blockers, ACE inhibitors, and aspirin), or hemodynamic response during MS between those with and without MSI. In univariate logistic regression analysis, each unit (1 mg/L) increase in CRP level was associated with 20% higher risk of MSI (OR 1.2, 95% CI 1.01-1.39, P=.04). This relationship remained in multivariate models. These data suggest that levels of CRP may be a risk marker for MSI in patients with CAD.

Mental stress and coronary artery disease: a multidisciplinary guide

Research suggests that acute and chronic stress are risk factors for the development and progression of coronary artery disease. Much of this work is multidisciplinary, using unfamiliar concepts deriving from disciplines other than cardiology and medicine. This article addresses and clarifies, for the cardiologist, some of the key concepts and issues in this area and provides an overview of evidence linking acute and chronic stress to cardiac pathology. Areas addressed include definitions and measurement of mental stress, methodological issues in stress research, and distinctions between stress and variables such as personality, emotion, and depression. Mental stress is a multifactorial process involving the environment, individual experiences and coping, and a set of neuroendocrine, autonomic, cardiovascular, and other systemic physiologic responses. There are difficulties identifying a single consensus physiologic stress measure because of individual differences in perceptions and physiologic response patterns. Nonetheless, important associations exist between mental stress and clinically relevant cardiovascular end points. As multidisciplinary research in this area continues, one major goal is the better integration of psychosocial knowledge and measures with cardiology research and practice.

Pathophysiological processes underlying emotional triggering of acute cardiac events

Acute negative emotional states may act as triggers of acute coronary syndrome (ACS), but the biological mechanisms involved are not known. Heightened platelet activation and hemodynamic shear stress provoked by acute stress may contribute. Here we investigated whether patients whose ACS had been preceded by acute anger, stress, or depression would show heightened hemodynamic and platelet activation in response to psychophysiological stress testing. We studied 34 male patients an average of 15 months after they had survived a documented ACS. According to an interview conducted within 5 days of hospital admission, 14 men had experienced acute negative emotion in the 2 h before symptom onset, and 20 men had not experienced any negative emotion. Hemodynamic variables and platelet activation were monitored during performance of challenging color-word interference and public speaking tasks and over a 2-h poststress recovery period. The emotion trigger group showed significantly greater increases in monocyte-platelet, leukocyte-platelet, and neutrophil-platelet aggregate responses to stress than the nontrigger group, after adjusting for age, body mass, smoking status, and medication. Monocyte-platelet aggregates remained elevated for 30 min after stress in the emotion trigger group. The emotion trigger group also showed poststress delayed recovery of systolic pressure and cardiac output compared with the nontrigger group. These results suggest that some patients with coronary artery disease may be particularly susceptible to emotional triggering of ACS because of heightened platelet activation in response to psychological stress, coupled with impaired hemodynamic poststress recovery.

Mental stress provokes ischemia in coronary artery disease subjects without exercise- or adenosine-induced ischemia

OBJECTIVES

The purpose of this study was to investigate the possibility that some patients with coronary artery disease (CAD) but negative exercise or chemical stress test results might have mental stress-induced ischemia. The study population consisted solely of those with negative test results.

BACKGROUND

Mental stress-induced ischemia has been reported in 20% to 70% of CAD subjects with exercise-induced ischemia. Because mechanisms of exercise and mental stress-induced ischemia may differ, we studied whether mental stress would produce ischemia in a proportion of subjects with CAD who have no inducible ischemia with exercise or pharmacologic tests.

METHODS

Twenty-one subjects (14 men, 7 women) with a mean age of 67 years and with a documented history of CAD were studied. All subjects had a recent negative nuclear stress test result (exercise or chemical). Subjects completed a speaking task involving role playing a difficult interpersonal situation. A total of 30 mCi 99mTc-sestamibi was injected at one minute into the speech, and imaging was started 40 min later. A resting image obtained within one week was compared with the stress image. Images were analyzed for number and severity of perfusion defects. The summed difference score based on the difference between summed stress and rest scores was calculated. Severity was assessed using a semiquantitative scoring method from zero to four.

RESULTS

Six of 21 (29%) subjects demonstrated reversible ischemia (summed difference score > or =3) with mental stress. No subject had chest pain or electrocardiographic changes during the stressor. Mean systolic and diastolic blood pressure and heart rate all increased between resting and times of peak stress.

CONCLUSIONS

Mental stress may produce ischemia in some subjects with CAD and negative exercise or chemical nuclear stress test results.

Effects of paroxetine on cardiovascular response to mental stress in subjects with a history of coronary artery disease and no psychiatric diagnoses

RATIONALE

Paroxetine may decrease mental stress-induced cardiovascular responses and so benefit individuals with heart disease, even those with no psychiatric illness.

OBJECTIVES

The effects of paroxetine on cardiovascular measures during a speech task were evaluated in psychiatrically healthy subjects with a history of coronary artery disease (CAD).

METHODS

Eight subjects completed this double-blind, placebo-controlled, cross-over study in which each subject took 1 month of paroxetine and 4 weeks of placebo in random order. While on each study, medication, blood pressure, heart rate, and plasma norepinephrine concentrations were measured during a period of relaxation and during a mental stressor. The mental stressor consisted of thinking about a stressful topic, speaking about the topic, and listening to a tape-recorded replay of the speech.

RESULTS

While on paroxetine, systolic blood pressure and diastolic blood pressure were 10-15% lower (p < 0.005) during the stressor, relative to measures obtained while on placebo. Pulse and plasma norepinephrine concentrations during stress trended lower during paroxetine treatment but did not reach statistical significance.

CONCLUSION

Paroxetine has antihypertensive properties during periods of psychological stress in psychiatrically healthy subjects with a history of CAD, and so should be evaluated for potential cardio-protective qualities.

Coping mechanisms, perception of health and cardiovascular dysfunction in Africans

The purpose of this study was to compare active and passive coping strategies of Africans with perception of own health and cardiovascular data. The subjects included 236 apparently healthy Africans (men=109; women=127). The COPE questionnaire was adapted, translated and validated for Africans. Scores on reliable sub-scales were used to classify men and women into more active coping (AC) and more passive coping (PC) subgroups. The General Health Questionnaire measured subjective perception of health. Blood pressure was recorded before and during application of the handgrip test, using the Finapres, a continuous non-invasive blood pressure monitor. Plasma renin activity (PRA) values, measured with radio immuno assay, were compared to blood pressure variables. Analyses of co-variance, adjusted for resting values and age, indicated that PC men responded with a larger increase in total peripheral resistance (TPR) (p=0.006), larger decrease in stroke volume (p=0.07), smaller increase in cardiac output (p=0.09) and larger increases in PRA resting (p=0.04) and reactivity (p< or =0.05) values. PC subjects reported a more negative perception of health than AC subjects. Young PC women presented greater hypertension prevalence rates (p< or =0.01) than AC women. In conclusion, all AC and PC subjects reacted with increased vascular reactivity on the handgrip test. PC men presented enhanced vascular reactivity, PRA and perception of poorer health values.

Relationship of socioeconomic markers to daily life ischemia and blood pressure reactivity in coronary artery disease patients

BACKGROUND

Socioeconomic status (SES) is an important predictor of clinical outcomes in patients with coronary artery disease (CAD).

PURPOSE

We hypothesized that a selected sample of low SES cardiac patients would display heightened cardiovascular stress responses in the laboratory and increased daily life ischemia compared to otherwise comparable higher SES patients.

METHODS

Eighty-two patients (M age=61.8+/-9.4 years; 71 men, 11 women) with a known history of CAD engaged in a stressful mental arithmetic task while blood pressure (BP) measures were collected. Myocardial ischemia was subsequently assessed via 48-hr ambulatory electrocardiographic monitoring in a subgroup of 51 patients. SES was defined by participants' residential block groups, which were linked to Census Bureau data about their neighborhood, including per capita income, percentage of the population below poverty, educational level, as well as self-report of number of years of education.

RESULTS

Contrary to expectation, high SES participants in the study displayed higher diastolic BP (p<.01) and systolic BP (p<.001) responses to mental stress in the laboratory.

CONCLUSIONS

Participants with daily life ischemia came from wealthier neighborhoods using indexes of poverty (p<.01), income (p<.02), and education (p<.04) compared to patients without ambulatory ischemia. This relationship was not accounted for by age, sex, race, body mass index, marital status, or measures of disease severity.

Relative-assessed psychological factors predict sedation requirement in critically ill patients

OBJECTIVE

Sedation is frequently required in critically ill, mechanically ventilated patients. Sedation and analgesia requirements may vary substantially among patients. This study examined whether psychological factors predict amount of sedation requirements beyond the effects of other biomedical parameters.

METHODS

This study used a prospective correlative design in an eight-bed medical intensive care unit at a tertiary university hospital. Fifty-five adult patients requiring mechanical ventilation were included. We evaluated by questionnaires three psychological factors of patients--hostility, anxiety and desire for control (DC)--as completed by patients' relatives at entry to the intensive care unit. Daily doses of sedatives required were monitored. The primary outcome measurement was midazolam dose expressed in mg/kg/h.

RESULTS

There was a statistically significant correlation between psychological factors and midazolam dose (mg/kg/h): r values = 0.40 for anxiety, 0.43 for hostility, and 0.46 for DC. Age and pulmonary edema were inversely related to midazolam requirements, whereas smoking, chronic obstructive pulmonary disease, fentanyl dose, and therapeutic intervention scoring system were positively correlated with midazolam doses. In a multiple regression, DC accounted for an additional and significant 5.4% of the variance in midazolam after controlling statistically for the effects of the significant background and biomedical predictors. In the final regression equation, DC and fentanyl were the only significant factors associated with higher sedation requirement.

CONCLUSION

Premorbid psychological profile independently predicts sedation requirement in critically ill, mechanically ventilated patients. Early identification of such a profile may help in sedation management and patient care. The possible mechanisms and clinical implications are discussed.

Comparison of mental stress-induced myocardial ischemia in coronary artery disease patients with versus without left ventricular dysfunction

To examine the susceptibility to myocardial ischemia with mental stress in patients who have coronary artery disease and normal left ventricular (LV) function versus those who have impaired LV function, we examined 58 patients who had coronary artery disease, including 22 who had normal LV function (ejection fraction >/=50%), 16 who had mild to moderate LV dysfunction (ejection fraction 30% to 50%), and 20 who had severe LV dysfunction (ejection fraction </=30%) and underwent bicycle and mental stress testing with myocardial perfusion scintigraphy on consecutive days in random order. Ischemia was assessed based on summed difference scores in regional rest versus stress myocardial perfusion and defined as a summed difference score >3. At comparable double products across the 3 groups, ischemia was induced with mental stress more frequently in patients who had severe LV dysfunction (50%) than in those who had normal LV function (9%; p <0.01). The frequency of exercise-induced ischemia was different only between those who had mild/moderate LV dysfunction and those who had normal LV function (56% vs 18%, respectively, p <0.05). The pattern of mental stress versus exercise ischemia differed between groups (p <0.02): there was a higher prevalence of mental stress ischemia versus exercise ischemia in patients who had severe LV dysfunction (p = 0.06), a marginally higher prevalence of exercise versus mental stress ischemia in those who had moderate LV dysfunction (p = 0.07), and no difference in mental stress versus exercise ischemia in those who had normal LV function. Thus, at comparable double products during mental stress and similar extent of coronary artery disease, ischemia with mental stress was induced more frequently in patients who had severe LV dysfunction than in those who had normal LV function. These data suggest that mental stress ischemia may be of particular clinical importance in patients who have coronary artery disease and LV dysfunction.

Is there a functional neural correlate of individual differences in cardiovascular reactivity?

OBJECTIVE

The present study tested whether individuals who differ in the magnitude of their blood pressure reactions to a behavioral stressor also differ in their stressor-induced patterns of functional neural activation.

METHODS

Sixteen participants (7 men, 9 women aged 47 to 72 years) were classified as high (n = 8) or low (n = 8) blood pressure reactors by the magnitude and temporal consistency of their systolic blood pressure (SBP) reaction to a Stroop color-word interference stressor. Both high and low SBP reactors completed this Stroop stressor while their task-related changes in blood pressure and functional neural activity were assessed in a blocked functional magnetic resonance imaging design.

RESULTS

In both high and low SBP reactors, the Stroop-stressor engaged the anterior cingulate, orbitofrontal, insular, posterior parietal, and the dorsolateral prefrontal regions of the cortex, the thalamus, and the cerebellum. Compared with low reactors, however, high reactors not only showed a larger magnitude increase in SBP to the Stroop stressor, but also an increased activation of the posterior cingulate cortex.

CONCLUSION

A behavioral stressor that is used widely in cardiovascular reactivity research, the Stroop stressor, engages brain systems that are thought to support both stressor processing and cardiovascular reactivity. Increased activation of the posterior cingulate, a brain region implicated in vigilance to the environment and evaluative emotional processes, may be a functional neural correlate of an individual's tendency to show large-magnitude (exaggerated) blood pressure reactions to behavioral stressors.

Heart rate variability

BACKGROUND

The authors conducted a study to evaluate the sensitivity of heart rate variability, or HRV, in quantifying the cardiocirculatory reaction to dental stress compared with other clinical parameters more frequently used in clinical practice.

METHODS

Twenty-five healthy subjects (15 men and 10 women aged 19 through 73 years) who underwent dental extractions were enrolled in the study. The authors measured systolic blood pressure, or SBP; diastolic blood pressure, or DBP; heart rate, or HR; and HRV at baseline, immediately after local anesthetic was administered, during the dental extraction and five minutes after the dental extraction. Time domain measures of HRV were based on interbeat intervals and were obtained by using standard deviations of the R-R intervals, which were calculated during a five-minute period in a continuous electrocardiographic record.

RESULTS

Analysis of variance for repeated measures showed no time-related difference between the four study periods with regard to SBP and DBP. However, HR values were significantly different in three of the four periods, and HRV values were significantly different in all four testing periods. Furthermore, HRV values exhibited greater variability in the maximum changes recorded during dental extractions compared with HR values (0 to 80 milliseconds versus 0 to 31 beats/minute, respectively).

CONCLUSIONS

HRV is a highly sensitive parameter for quantifying the sympathetic drive to the heart during a cardiovascular reaction to a dental operation.

CLINICAL IMPLICATIONS

Clinicians may find that HRV evaluation is useful in monitoring patients with heart disease to detect early signs of cardiac impairment related to local, high sympathetic activity and to prevent cardiovascular emergencies.

Acute and chronic psychological stress in coronary disease

PURPOSE OF REVIEW

Coronary artery disease (CAD) is the leading cause of death in the United States and other developed countries. Along with a number of other factors thought to contribute to the high prevalence of CAD in developed societies (longer life expectancy, obesity, sedentary lifestyles), various psychological and social factors appear to promote the development or worsening of heart disease. It is well recognized that stress can be harmful to the cardiovascular system. The combination of the preexisting vulnerability and the major stressor are believed to result in cardiac arrhythmias and/or plaque rupture leading to death.

RECENT FINDINGS

Recently, the epidemiologic evidence of a link between stress and CAD is very convincing, yet the biopsychosocial pathway that would explain how stress can lead to disease is less clear. Different types of psychological stress have been found to be associated with increased cardiovascular events. Evidence regarding the efficacy of psychosocial interventions is also presented.

SUMMARY

It is suggested that, taken as a whole, evidence for a psychological and social impact on CAD morbidity and mortality is convincing.

Peripheral arterial tonometry: a diagnostic method for detection of myocardial ischemia induced during mental stress tests: a pilot study

BACKGROUND

Mental stress testing is considered a reliable method for diagnosing patients with coronary heart disease (CHD) who may be at risk for future events. It has been shown recently that myocardial ischemia induced during mental stress tests is specifically associated with peripheral arterial vasoconstriction.

HYPOTHESIS

The study was undertaken to test the diagnostic capability of peripheral arterial tonometry (PAT) to detect peripheral arterial vasomotor changes.

METHODS

We monitored pulsatile finger blood volume changes using a specially designed finger plethysmograph, PAT that can detect peripheral arterial vasomotor changes. Equilibrium radionuclide angiography (ERNA) was simultaneously performed in 18 male patients at rest and during a mental arithmetic stress test with harassment. All patients had previously diagnosed coronary disease and positive exercise tests. Myocardial ischemia was diagnosed by ERNA when global ejection fraction fell > or = 8% during mental stress or new (or worsened) focal wall motion abnormalities occurred. Peripheral arterial tonometry tracings were considered abnormal when the pulse wave amplitude decreased by > or = 20% from baseline.

RESULTS

In 18 patients there were 16 usable studies. In eight patients, both ERNA and PAT were abnormal, and in six patients the tests were negative by both methods. In two cases, the results were discordant. Therefore, when considering an abnormal PAT tracing as indicative of mental stress-driven myocardial ischemia, concordance of the two methods was 88%.

CONCLUSION

The use of PAT may facilitate both clinical testing and research during mental stress.

Perceived stress as a predictor of the self-reported new diagnosis of symptomatic CHD in older women

This article describes one aspect of a prospective cohort study of 10,432 women aged between 70 and 75 years. After a 3-year period, 503 women self-reported a new diagnosis by a doctor of angina or myocardial infarction (symptomatic coronary heart disease [CHD]). Time one psychosocial variables (Duke Social Support Index, time pressure, Perceived Stress Scale, Mental Health Index, having a partner, educational attainment, and location of residence) were analyzed using univariate binary logistic regression for their ability to predict subsequent symptomatic CHD. Of these variables, the Duke Social Support Index, Perceived Stress Scale and the Mental Health Index were found to be significant predictors of symptomatic CHD diagnosis. Only the Perceived Stress Scale, however, proved to be a significant independent predictor. After controlling for time one nonpsychosocial variables, as well as the frequency of family doctor visits, perceived stress remained a significant predictor of the new diagnosis of symptomatic CHD in this cohort of older women over a 3-year period.

Simultaneous assessment of myocardial perfusion and function during mental stress in patients with chronic coronary artery disease

BACKGROUND

Mental stress (MS) is an important provocateur of myocardial ischemia in many patients with chronic coronary artery disease. The majority of laboratory assessments of ischemia in response to MS have included measurements of either myocardial perfusion or function alone. We performed this study to determine the relationship between alterations in perfusion and ventricular function during MS. Methods and results Twenty-eight patients with reversible perfusion defects on exercise or pharmacologic stress myocardial perfusion imaging (MPI) underwent simultaneous technetium 99m sestamibi single photon emission computed tomography (SPECT) MPI and transthoracic echocardiography at rest and during MS according to a mental arithmetic protocol. In all cases the MS study was performed within 4 weeks of the initial exercise or pharmacologic MPI that demonstrated ischemia. SPECT studies were analyzed visually with the use of a 13-segment model and quantitatively by semiautomated circumferential profile analysis. Echocardiograms were graded on a segmental model for regional wall motion on a 4-point scale. Of 28 patients, 18 (64%) had perfusion defects and/or left ventricular dysfunction develop during MS: 9 (32%) had myocardial perfusion defects develop, 6 (21%) had regional or global left ventricular dysfunction develop, and 3 (11%) had both perfusion defects and left ventricular dysfunction develop. The overall concordance between perfusion and function criteria for ischemia during MS was only 46%. Among 9 patients with MS-induced left ventricular dysfunction, 5 had new regional wall motion abnormalities and 4 had a global decrement in function. In patients with MS-induced ischemia by SPECT, the number of reversible perfusion defects was similar during both MS and exercise/pharmacologic stress (2.8 +/- 2.0 vs 3.5 +/- 1.8, P =.41). Hemodynamic changes during MS were similar whether patients were divided on the basis of perfusion defects or left ventricular dysfunction during MS.

CONCLUSIONS

These data indicate the feasibility of simultaneous assessment of perfusion and function responses during MS. Flow and function responses to MS are frequently not concordant. These data suggest that MS-induced changes in perfusion may represent a different phenomenon than MS-induced changes in left ventricular function (either globally or regionally).

Cardiovascular reactivity and development of preclinical and clinical disease states

OBJECTIVE

The objective of this review is to evaluate the evidence for the hypothesis that cardiovascular reactivity can predict the development of preclinical (elevated blood pressure, ventricular remodeling, carotid atherosclerosis) and/or clinical cardiovascular disease states.

METHODS

A review of the literature was conducted examining prospective studies.

RESULTS

Three large epidemiological studies with long-term follow-up periods (20 years or more) have found blood pressure responses to the cold pressor task to be predictive of subsequent essential hypertension in initially normotensive samples. Studies showing less consistent results have tended to use shorter-term follow-up periods. A larger body of literature demonstrates consistent associations between stress-related cardiovascular reactivity and blood pressure elevations in youth over the course of 1 to 6 years; such relationships have not been consistently shown among adult samples. Moderately consistent evidence points to a positive relationship between reactivity and other measures of subclinical disease (increased left ventricular mass and carotid atherosclerosis) among the few prospective studies that have examined these issues to date. A number of additional factors, however, such as baseline levels of disease risk and exposure to psychosocial stress, seem to moderate these relationships. Health status at baseline also seems to moderate the association between reactivity and clinical coronary heart disease in recent reports: two of three existing studies in initially healthy samples show no evidence of a relationship between reactivity and clinical outcomes, whereas three of four studies in samples with preexisting coronary heart disease or essential hypertension show a positive relationship between reactivity and subsequent disease states.

CONCLUSIONS

There is reasonable evidence to suggest that cardiovascular reactivity can predict the development of some preclinical states (eg, increased left ventricular mass and blood pressure) states and perhaps even new clinical events in some patients with essential hypertension or coronary heart disease. However, much more information is needed concerning moderating and potentially confounding variables before the robustness of the positive relationships can become clinically useful.

Prognostic implication of ergonovine echocardiography in patients with near normal coronary angiogram or negative stress test for significant fixed stenosis

OBJECTIVES

The goal of this study was to assess the prognostic value of ergonovine echocardiography (Erg Echo) for diagnosis of coronary vasospasm (CVS) in patients without significant fixed coronary stenosis.

MATERIAL AND METHODS

Medical records of 650 patients who underwent Erg Echo were reviewed. Before Erg Echo, absence of significant fixed coronary stenosis was confirmed by invasive coronary angiography (CAG) in 316 patients (49%) or by noninvasive confirmation of negative treadmill or normal myocardial perfusion scan in 334 patients (51%). The cardiac events after Erg Echo were tabulated and these included cardiac death, myocardial infarction (MI), readmission due to intractable chest pain.

RESULTS

The average age was 54 +/- 10 years, with 223 women and 427 men. Erg Echo was positive in 237 patients (36%), for whom long-acting calcium channel blocker and nitrates were prescribed. During follow-up (46 +/- 23 months), cardiac events developed in 13% (30 of 237) of the positive Erg Echo group and 3% (14 of 413) of the negative Erg Echo group (P <.001). Incidence of cardiac death was higher in the positive Erg Echo group (3.4% vs 0.7%, P =.022). The 5-year survival rate (93% +/- 3% vs 99% +/- 1%, P =.013) and event-free survival rate (94% +/- 2% vs 77% +/- 6%, P <.001) were significantly lower in the positive Erg Echo group. Smoking (hazards ratio 6.3; 95% CI 1.7-23.5) and multivessel spasm (hazards ratio 37.2, 95% CI, 8.1 to 170.4) were independent factors associated with cardiac death and/or MI.

CONCLUSION

Erg Echo for noninvasive diagnosis of CVS in the differential diagnosis of chest pain provides useful prognostic information for patients without significant fixed coronary stenosis and can play a role as a cost-effective diagnostic strategy in these selected patients.

Mental stress response, arterial stiffness, and baroreflex sensitivity in healthy aging

This study examined the relationship of pressor responses during mental stress to arterial stiffness and baroreflex sensitivity. Hemodynamic responses of 24 healthy individuals (51-86 years old) to two mental stress tasks (math and speech) were compared with common carotid artery mechanical stiffness and autonomic nervous system regulation of blood pressure as measured by using the modified Oxford technique. At the ages studied, no effect of age on stress task responsiveness, carotid stiffness, or baroreflex sensitivity was observed. Carotid stiffness and baroreflex sensitivity demonstrated a strong inverse relation. Change in heart rate during the speech task was correlated with arterial stiffness, and the increase in mean arterial pressure was associated with carotid stiffness and was inversely correlated to baroreflex sensitivity. These associations suggest that acute hemodynamic reactions to mental stress among healthy adults are determined, in part, by structural properties of arterial vessels and sensitivity of arterial baroreflex. These observations may provide a mechanistic link between the physiology of cardiovascular reactivity to stress and risk of cardiovascular events in middle-aged and older individuals.

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.

Effects of psychological and social factors on organic disease: a critical assessment of research on coronary heart disease

An extensive research literature in the behavioral sciences and medicine suggests that psychological and social factors may play a direct role in organic coronary artery disease (CAD) pathology. However, many in the medical and scientific community regard this evidence with skepticism. This chapter critically examines research on the impact of psychological and psychosocial factors on the development and outcome of coronary heart disease, with particular emphasis on studies employing verifiable outcomes of CAD morbidity or mortality. Five key variables identified as possible psychosocial risk factors for CAD are addressed: acute and chronic stress, hostility, depression, social support, and socioeconomic status. Evidence regarding the efficacy of psychosocial interventions is also presented. It is suggested that, taken as a whole, evidence for a psychological and social impact on CAD morbidity and mortality is convincing. However, continued progress in this area requires multidisciplinary research integrating expertise in cardiology and the behavioral sciences, and more effective efforts to communicate research findings to a biomedical audience.

Mental stress-induced ischemia and all-cause mortality in patients with coronary artery disease: Results from the Psychophysiological Investigations of Myocardial Ischemia study

BACKGROUND

Ischemia during laboratory mental stress tests has been linked to significantly higher rates of adverse cardiac events. Previous studies have not been designed to detect differences in mortality rates.

METHODS AND RESULTS

To determine whether mental stress-induced ischemia predicts death, we evaluated 196 patients from the Psychophysiological Investigations of Myocardial Ischemia (PIMI) study who had documented coronary artery disease and exercise-induced ischemia. Participants underwent bicycle exercise and psychological stress testing with radionuclide imaging. Cardiac function data and psychological test results were collected. Vital status was ascertained by telephone and by querying Social Security records 3.5+/-0.4 years and 5.2+/-0.4 years later. Of the 17 participants who had died, new or worsened wall motion abnormalities during the speech test were present in 40% compared with 19% of survivors (P=0.04) and significantly predicted death (rate ratio=3.0; 95% CI, 1.04 to 8.36; P=0.04). Ejection fraction changes during the speech test were similar in patients who died and in survivors (P=0.9) and did not predict death even after adjusting for resting ejection fraction (P=0.63), which was similar in both groups (mean, 56.4 versus 59.7; P=0.24). Other indicators of ischemia during the speech test (ST-segment depression, chest pain) did not predict death, nor did psychological traits, hemodynamic responses to the speech test, or markers of the presence and severity of ischemia during daily life and exercise.

CONCLUSIONS

In patients with coronary artery disease and exercise-induced ischemia, the presence of mental stress-induced ischemia predicts subsequent death.

Usefulness of psychosocial treatment of mental stress-induced myocardial ischemia in men

This study examined the effects of exercise and stress management training on clinical outcomes and medical expenditures over a 5-year follow-up period in 94 male patients with established coronary artery disease (CAD) and evidence of ambulatory or mental stress-induced myocardial ischemia. Patients were randomly assigned to 4 months of aerobic exercise 3 times per week or to a 1.5-hour weekly class on stress management; patients who lived too far from Duke to participate in the weekly treatments formed the usual care control group. Follow-up was performed at the end of treatment and annually thereafter for 5 years. Stress management was associated with a significant reduction in clinical CAD events relative to usual care over each of the first 2 years of follow-up and after 5 years. Economic analyses revealed that stress management was associated with lower medical costs than usual care and exercise in the first 2 years, and that the cumulative cost over 5 years was also lower for stress management relative to usual care. These results suggest that there may be clinical and economic benefit to offering the type of preventive stress management and exercise interventions provided to patients with myocardial ischemia. Moreover, these findings suggest that the financial benefits that accrue from an appropriately targeted intervention may be substantial and immediate.

Effects of mental stress on coronary epicardial vasomotion and flow velocity in coronary artery disease: relationship with hemodynamic stress responses

OBJECTIVES

This study examines the prevalence and hemodynamic determinants of mental stress-induced coronary vasoconstriction in patients undergoing diagnostic coronary angiography.

BACKGROUND

Decreased myocardial supply is involved in myocardial ischemia triggered by mental stress, but the determinants of stress-induced coronary constriction and flow velocity responses are not well understood.

METHODS

Coronary vasomotion was assessed in 76 patients (average age 59.9 +/- 10.4 years; eight women). Coronary flow velocity responses were assessed in 20 of the 76 patients using intracoronary Doppler flow. Repeated angiograms were obtained after a baseline control period, a 3-min mental arithmetic task and administration of 200 microg intracoronary nitroglycerin. Arterial blood pressure (BP) and heart rate assessments were made throughout the procedure.

RESULTS

Mental stress resulted in significant BP and heart rate increases (p < 0.001). Coronary constriction (>0.15 mm) was observed in 11 of 59 patients with coronary artery disease (CAD) (18.6%). Higher mental stress pressor responses were associated with more constriction in diseased segments (rdeltaSBP = -0.26, rdeltaDBP = -0.30, rdeltaMAP = -0.29; p's < 0.05) but not with responses in nonstenotic segments. The overall constriction of diseased segments was not significant (p > 0.10), whereas a small but significant constriction occurred in nonstenotic segments (p = 0.04). Coronary flow velocity increased in patients without CAD (32.2%; p = 0.008), but not in patients with CAD (6.4%; p = ns). Cardiovascular risk factors were not predictive of stress-induced vasomotion in patients with CAD.

CONCLUSIONS

Coronary vasoconstriction in angiographically diseased arteries varies with hemodynamic responses to mental arousal. Coronary flow responses are attenuated in CAD patients. Thus, combined increases in cardiac demand and concomitant reduced myocardial blood supply may contribute to myocardial ischemia with mental stress.

The perception of available social support is related to reduced cardiovascular reactivity in Phase II cardiac rehabilitation patients

OBJECTIVE

Numerous studies have observed a relationship between social support (SS) and post coronary event survival. Laboratory research suggests one mechanism regulating this relationship may be exaggerated cardiovascular reactivity (CVR). What has not been as well explored is (1) whether the SS-CVR relationship holds up for a heart diseased sample, and (2) whether this relationship is evidenced only in supportive environments or can be found as a function of generalized perception of being socially supported. Thus, the purpose of this study was to examine the relationship of perceived SS and a locally supportive presence to CVR to a speech-induced stressor in post coronary event patients.

METHOD

Forty-one Phase II cardiac rehabilitation patients participated in a research protocol that consisted of BP and HR measurement during two identical affective stress interviews where local support was systematically varied by presence or absence of a friendly small pet dog. Perception of SS was assessed by completion of psychosocial questionnaire packet that included measures of SS, anger expression and pet attachment.

RESULTS

Repeated measures ANCOVAs revealed that patients who believed they had greater SS available to them during difficult times exhibited significantly less CVR for MAP (p<.007) and DBP (p<.024). No significant main effects for local support (pet presence) and no interactions between local and perceived support were found.

CONCLUSIONS

These findings are of interest as they: (a) demonstrate an association between reduced CVR and higher (amounts of) SS in a clinical sample; (b) demonstrate this effect in a sample medicated to dampen CV levels and surges; (c) suggest that perceived amount of SS provides an ameliorative influence on CVR independent of situational support; (d) suggest that for certain conditions pet-models of support may be ineffective at establishing an local support presence.