ACCTG 1 Lecture Notes - Lecture 18: Myocardial Infarction, Coronary Circulation, Cardiovascular Disease
The interaction between psychologic distress and biobehavioural
processes in cardiovascular disease
Introduction
Myocardial infarction and sudden cardiac death can be triggered by emotional distress [1,2]. The
vulnerability for these acute coronary syndromes is primarily determined by the presence of coronary
artery disease (CAD) and/or structural myocardial damage. Chronic psychiatric, psychologic and
social conditions can influence the gradual progression of cardiovascular disease and may further
enhance the likelihood or magnitude of emotion-related triggers of acute coronary syndromes,
primarily in patients with underlying cardiovascular disease [3,4]. The progression of early stages of
cardiovascular disease to its clinical manifestation as acute coronary syndromes can in most cases be
described in three phases: gradual subclinical disease progression, the vulnerable disease stage, and
the presentation of acute coronary syndromes.
We have previously proposed a three-category classification framework of cardiovascular
psychologic risk factors based on the duration and temporal proximity to the occurrence of coronary
syndromes: (1) acute psychologic risk factors (e.g. outbursts of anger, mental activity, and acute
distress) that may act as triggers of cardiac events within one hour; (2) episodic psychologic risk
factors with a duration lasting from several weeks to two years (e.g. depression, exhaustion and
episodes of distress related to job loss, divorce and exposure to extreme physical or mental adversity);
and (3) chronic psychologic risk factors that promote the gradual progression of coronary artery
disease (e.g. personality traits and adverse
socioenvironmental circumstances).
Chronic psychologic factors are associated
with increased reactivity to acute stressors
and also promote the risk of the development
of episodic psychologic risk factors. Recent
evidence also suggests that episodic risk
factors such as depression are associated with
an increased emotional and biologic response
to acute stressors. These types of psychologic
risk factors are associated with characteristic
biologic and physiologic processes that play distinct roles at different disease stages. These
psychologic risk factors often coincide and also need to be understood in the context of genetic
background factors and traditional cardiovascular risk factors such as hypertension, dyslipidemia and
diabetes mellitus.
Distress and other psychologic risk factors may have direct physiologic and biologic effects relevant
to CAD progression. In addition, risk associated with psychologic distress may be mediated by
adverse health behaviors such as smoking [5] and traditional CVD (cardiovascular disease) risk
factors (e.g., hypertension, dyslipidemia, and metabolic syndrome). The majority of patients at risk of
adverse cardiac outcomes based on psychologic factors do not have clinical psychiatric disorders.
Definition of psychologic distress
Psychologic distress can be broadly defined as a negative internal state of the individual that is
dependent on interpretation or appraisal of threat, harm, or demand. Multiple methods exist to assess
psychologic distress (e.g. self-report questionnares, observations, interviews). . It is important to
evaluate psychologic distress in terms of its environmental precipitants (i.e. life events) and factors
that may increase vulnerability to these events (i.e. low
socioeconomic status, discrimination, and adverse early
life experiences) as well as psychologic and social factors
that can act as buffers (social support, coping style and
resources, and optimism). A general factor of
“psychologic distress” incorporates a large portion of the
predictive values of various specific psychologic
cardiovascular risk factors including depression, anxiety,
hostility, and low perceived social support.
Severe and prolonged uncontrollable distress may result
in clinical and subclinical states characterized by
negative affect that commonly occur in psychiatric
practice (e.g. depression) and conditions that commonly fall outside the range of clinical psychiatry
such as burn-out and vital exhaustion. The increased cardiovascular disease risk associated with
depression emerges at levels well below clinical diagnostic criteria (i.e. sub-syndromal) for Major
Depressive Disorder.
Psychologic distress and cardiovascular disease
Clinical epidemiologic studies have shown that psychologic distress [12] and related psychologic
factors such as depressive symptoms, anxiety, and hostility contribute to cardiovascular disease
progression. Psychologic distress will be reviewed in terms of acute, episodic and chronic distress.
Acute distress is of critical importance as a potential trigger of acute coronary syndromes and cardiac
arrhythmias in vulnerable individuals. In addition, prolonged and repeated exposures to shortterm
stressors and resulting acute distress responses may result in cumulative effects relevant to gradual
cardiac and vascular disease progression.
Acute distress as trigger of cardiac events
Approximately 1 in 5 acute coronary syndromes are preceded by an acute trigger. Substantial
increases in central and autonomic nervous system activity are a common phenomenon that link acute
psychologic, psychiatric and neurologic events to major cardiac pathologies. We will first review
triggers of acute coronary syndromes (sudden cardiac death, myocardial infarction, and unstable
angina reflecting severe myocardial ischemia) and arrhythmic events, followed by other outcomes
(acute heart failure, takotsubo syndrome). Acute psychologic distress also plays a contributing role in
clinical syndromes in the absence of well-defined anatomical or structural disease.
For example, Prinzmetal’s angina (also referred to as “variant” angina), involves a transient increase
in coronary vascular tone and substantial focal constriction (vasospasm). This disorder is more
common in patients with vasospastic disorders such as migraine and Raynaud’s disease. Emotional
distress may play a role in Prinzmetal’s angina, but few studies have systematically addressed this
condition. Another clinical setting in which acute distress and especially panic plays a role is “non-
cardiac chest pain”. This is complicated, as angina can occur as a result of abnormal tone of the
microvascular (resistence) vessels with normal or near normal (conductance) coronary arteries.
Although myocardial infarction (MI) virtually always occurs in the presence of underlying coronary
artery disease, the coronary disease severity prior to infarction is often not obstructive (i.e. less than
50% coronary stenosis). Myocardial infarctions that are triggered by acute physical or emotional
stressors are not necessarily associated with more severe underlying coronary disease and also not
with a worse one-year prognosis.
Document Summary
The interaction between psychologic distress and biobehavioural processes in cardiovascular disease. Myocardial infarction and sudden cardiac death can be triggered by emotional distress [1,2]. The vulnerability for these acute coronary syndromes is primarily determined by the presence of coronary artery disease (cad) and/or structural myocardial damage. Chronic psychiatric, psychologic and social conditions can influence the gradual progression of cardiovascular disease and may further enhance the likelihood or magnitude of emotion-related triggers of acute coronary syndromes, primarily in patients with underlying cardiovascular disease [3,4]. Chronic psychologic factors are associated with increased reactivity to acute stressors and also promote the risk of the development of episodic psychologic risk factors. Recent evidence also suggests that episodic risk factors such as depression are associated with an increased emotional and biologic response to acute stressors. These types of psychologic risk factors are associated with characteristic biologic and physiologic processes that play distinct roles at different disease stages.
