Mental stress-induced myocardial ischemia | |
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Specialty | Cardiology |
Causes | Reduced mental stress threshold levels affected by genetic predispositions and life experiences |
Frequency | In patients with stable coronary heart disease (CHD) up to 70% [1] |
Mental stress-induced myocardial ischemia (MSIMI) is a medical condition in which acute psychological stress can trigger a transient myocardial ischemia, which is a state of reduced blood flow to the heart muscle, often without the presence of significant coronary artery disease (CAD). [2] [3] [4] [5] [1] It is distinct from conventional stress ischemia caused by physical exertion or pharmacological agents. [3] MSIMI is often silent and detected through specific cardiac function tests during mental stress challenges. [6]
Mental stress triggers various physiological changes in the body, activating mechanisms such as the autonomic nervous system (ANS) and the hypothalamic–pituitary–adrenal axis (HPA), resulting in hemodynamic, neuroendocrine, and immune responses. Typically, these responses are adaptive and help individuals cope with environmental changes, referred to as the "defense response," which prepares them for fight or flight. Consequently, the risk of cardiovascular (CV) events resulting from mental stress is influenced by external factors and an individual's stress threshold, which is shaped by genetic predispositions and life experiences. This variability explains why people respond differently to stressors. [5]
Mental stress-induced myocardial ischemia involves abnormal microvascular vasoreactivity and inflammation, with increased brain activity in regions that modulate autonomic nervous system reactivity to emotional stress, fear. [2] [7] Emotional responses and certain psychological traits may influence the occurrence of MSIMI. [6] MSIMI can occur at lower cardiac workloads, independent of hemodynamic changes, and is not directly related to the severity of angiographic CHD. [3] It can occur in patients with normal cardiac stress testing and can often be silent. [2]
MSIMI is associated with a twofold increased risk of major adverse cardiovascular events (MACE) compared to those without MSIMI. It is particularly prevalent among young women with myocardial infarction (MI) and those with psychological comorbidities. [2]
Studies have found that young women who have had a myocardial infarction are twice as likely to develop mental stress-induced myocardial ischemia (MSIMI) compared to men of similar age. [4]
Various techniques like electrocardiogram (ECG), echocardiography, and positron emission tomography (PET) are used to assess MSIMI. The incidence of MSIMI has varied across studies due to different assessment methods and mental stressors. [6]
Current research focuses on understanding stress pathways in CAD and integrating mental health, behavioral medicine with routine cardiology care to improve patient outcomes. [2]
Approximately 30% of CAD patients experience MSIMI under mental stress, which typically is silent and not related to the severity of CAD. [6]
Coronary artery disease (CAD), also called coronary heart disease (CHD), ischemic heart disease (IHD), myocardial ischemia, or simply heart disease, involves the reduction of blood flow to the cardiac muscle due to build-up of atherosclerotic plaque in the arteries of the heart. It is the most common of the cardiovascular diseases. Types include stable angina, unstable angina, and myocardial infarction.
Angina, also known as angina pectoris, is chest pain or pressure, usually caused by insufficient blood flow to the heart muscle (myocardium). It is most commonly a symptom of coronary artery disease.
Coronary artery bypass surgery, also known as coronary artery bypass graft, is a surgical procedure to treat coronary artery disease (CAD), the buildup of plaques in the arteries of the heart. It can relieve chest pain caused by CAD, slow the progression of CAD, and increase life expectancy. It aims to bypass narrowings in heart arteries by using arteries or veins harvested from other parts of the body, thus restoring adequate blood supply to the previously ischemic heart.
A cardiac stress test is a cardiological examination that evaluates the cardiovascular system's response to external stress within a controlled clinical setting. This stress response can be induced through physical exercise or intravenous pharmacological stimulation of heart rate.
An atheroma, or atheromatous plaque, is an abnormal accumulation of material in the inner layer of an arterial wall.
Acute coronary syndrome (ACS) is a syndrome due to decreased blood flow in the coronary arteries such that part of the heart muscle is unable to function properly or dies. The most common symptom is centrally located pressure-like chest pain, often radiating to the left shoulder or angle of the jaw, and associated with nausea and sweating. Many people with acute coronary syndromes present with symptoms other than chest pain, particularly women, older people, and people with diabetes mellitus.
Unstable angina is a type of angina pectoris that is irregular or more easily provoked. It is classified as a type of acute coronary syndrome.
Percutaneous coronary intervention (PCI) is a minimally invasive non-surgical procedure used to treat narrowing of the coronary arteries of the heart found in coronary artery disease. The procedure is used to place and deploy coronary stents, a permanent wire-meshed tube, to open narrowed coronary arteries. PCI is considered 'non-surgical' as it uses a small hole in a peripheral artery (leg/arm) to gain access to the arterial system, an equivalent surgical procedure would involve the opening of the chest wall to gain access to the heart area. The term 'coronary angioplasty with stent' is synonymous with PCI. The procedure visualises the blood vessels via fluoroscopic imaging and contrast dyes. PCI is performed by an interventional cardiologists in a catheterization laboratory setting.
Coronary vasospasm refers to when a coronary artery suddenly undergoes either complete or sub-total temporary occlusion.
Takotsubo cardiomyopathy or takotsubo syndrome (TTS), also known as stress cardiomyopathy, is a type of non-ischemic cardiomyopathy in which there is a sudden temporary weakening of the muscular portion of the heart. It usually appears after a significant stressor, either physical or emotional; when caused by the latter, the condition is sometimes called broken heart syndrome.
Myocardial perfusion imaging or scanning is a nuclear medicine procedure that illustrates the function of the heart muscle (myocardium).
Coronary ischemia, myocardial ischemia, or cardiac ischemia, is a medical term for a reduced blood flow in the coronary circulation through the coronary arteries. Coronary ischemia is linked to heart disease, and heart attacks. Coronary arteries deliver oxygen-rich blood to the heart muscle. Reduced blood flow to the heart associated with coronary ischemia can result in inadequate oxygen supply to the heart muscle. When oxygen supply to the heart is unable to keep up with oxygen demand from the muscle, the result is the characteristic symptoms of coronary ischemia, the most common of which is chest pain. Chest pain due to coronary ischemia commonly radiates to the arm or neck. Certain individuals such as women, diabetics, and the elderly may present with more varied symptoms. If blood flow through the coronary arteries is stopped completely, cardiac muscle cells may die, known as a myocardial infarction, or heart attack.
A myocardial infarction (MI), commonly known as a heart attack, occurs when blood flow decreases or stops in one of the coronary arteries of the heart, causing infarction to the heart muscle. The most common symptom is chest pain or discomfort which may travel into the shoulder, arm, back, neck or jaw. Often such pain occurs in the center or left side of the chest and lasts for more than a few minutes. The discomfort may occasionally feel like heartburn.
Coronary perfusion pressure (CPP) refers to the pressure gradient that drives coronary blood pressure. The heart's function is to perfuse blood to the body; however, the heart's own myocardium must, itself, be supplied for its own muscle function. The heart is supplied by coronary vessels, and therefore CPP is the blood pressure within those vessels. If pressures are too low in the coronary vasculature, then the myocardium risks ischemia with subsequent myocardial infarction or cardiogenic shock.
Myocardial infarction complications may occur immediately following a myocardial infarction, or may need time to develop. After an infarction, an obvious complication is a second infarction, which may occur in the domain of another atherosclerotic coronary artery, or in the same zone if there are any live cells left in the infarct.
A diagnosis of myocardial infarction is created by integrating the history of the presenting illness and physical examination with electrocardiogram findings and cardiac markers. A coronary angiogram allows visualization of narrowings or obstructions on the heart vessels, and therapeutic measures can follow immediately. At autopsy, a pathologist can diagnose a myocardial infarction based on anatomopathological findings.
Management of acute coronary syndrome is targeted against the effects of reduced blood flow to the affected area of the heart muscle, usually because of a blood clot in one of the coronary arteries, the vessels that supply oxygenated blood to the myocardium. This is achieved with urgent hospitalization and medical therapy, including drugs that relieve chest pain and reduce the size of the infarct, and drugs that inhibit clot formation; for a subset of patients invasive measures are also employed. Basic principles of management are the same for all types of acute coronary syndrome. However, some important aspects of treatment depend on the presence or absence of elevation of the ST segment on the electrocardiogram, which classifies cases upon presentation to either ST segment elevation myocardial infarction (STEMI) or non-ST elevation acute coronary syndrome (NST-ACS); the latter includes unstable angina and non-ST elevation myocardial infarction (NSTEMI). Treatment is generally more aggressive for STEMI patients, and reperfusion therapy is more often reserved for them. Long-term therapy is necessary for prevention of recurrent events and complications.
Kounis syndrome is defined as acute coronary syndrome caused by an allergic reaction or a strong immune reaction to a drug or other substance. It is a rare syndrome with authentic cases reported in 130 males and 45 females, as reviewed in 2017; however, the disorder is suspected of being commonly overlooked and therefore much more prevalent. Mast cell activation and release of inflammatory cytokines as well as other inflammatory agents from the reaction leads to spasm of the arteries leading to the heart muscle or a plaque breaking free and blocking one or more of those arteries.
Remote ischemic conditioning (RIC) is an experimental medical procedure that aims to reduce the severity of ischaemic injury to an organ such as the heart or the brain, most commonly in the situation of a heart attack or a stroke, or during procedures such as heart surgery when the heart may temporary suffer ischaemia during the operation, by triggering the body's natural protection against tissue injury. Although noted to have some benefits in experimental models in animals, this is still an experimental procedure in humans and initial evidence from small studies have not been replicated in larger clinical trials. Successive clinical trials have failed to identify evidence supporting a protective role in humans.
George "Rick" Stouffer is an American cardiologist who is Chief of the Division of Cardiology at the University of North Carolina Medical Center, where he is a practicing interventional cardiologist. Stouffer was awarded the Ernest and Hazel Craige Distinguished Professorship of Medicine in 2018; prior to that he was the Henry A. Foscue Distinguished Professor of Medicine. Stouffer is also co-director of the McAllister Heart Institute. He is known for his research regarding inpatient ST elevation myocardial infarctions.