Ischemic Heart Disease

What happens in ischemic heart disease

The heart muscle is supplied by the coronary arteries. Narrowing of these arteries is described in detail under coronary artery disease. Ischemia means the muscle is receiving less oxygen than it needs. The main cause is atherosclerosis: cholesterol, inflammatory cells and calcium build up as plaque in the artery wall over decades, narrowing the vessel.

• When narrowing is significant, blood flow is adequate at rest but not during exertion, causing stable angina.
• If a plaque ruptures, a blood clot forms on it and can suddenly block the artery, causing acute coronary syndrome: unstable angina or a heart attack.
• Repeated or prolonged ischemia damages heart muscle, leading to ischemic cardiomyopathy and heart failure.

Other mechanisms

• Coronary microvascular dysfunction: the tiny vessels do not dilate properly, causing angina with normal-looking main arteries. More common in women.
• Coronary vasospasm: temporary spasm of an artery, often at rest or at night.
• Spontaneous coronary artery dissection (SCAD): a tear in the artery wall, mostly in younger women, including around pregnancy.
• Supply-demand mismatch: severe anemia, very fast heart rhythms or low blood pressure can cause ischemia in a vulnerable heart.

Forms of ischemic heart disease

Symptoms

Angina

Angina is the typical symptom:

• pressure, tightness, squeezing, heaviness or burning in the chest
• spreading to the left or both arms, jaw, neck, back or upper belly
• brought on by exertion, cold, heavy meals or emotional stress
• relieved within minutes by rest or nitroglycerin

Other symptoms

• shortness of breath on exertion
• unusual tiredness
• nausea, sweating or lightheadedness
• palpitations

Women, older adults and people with diabetes are more likely to have less typical symptoms, such as breathlessness, fatigue, nausea, or pain in the back, jaw or upper belly.

Risk factors

Cannot be changed

• age: men over 45, women over 55
• male sex, though heart disease is the leading cause of death in women too
• family history of early heart disease
• South Asian ancestry and some other ethnic backgrounds
• high lipoprotein(a)

Can be changed

• smoking
• high blood pressure
• high LDL cholesterol
• diabetes
• obesity, especially around the waist
• physical inactivity
• unhealthy diet
• excess alcohol
• chronic kidney disease
• chronic stress, depression and poor sleep
• pregnancy complications such as preeclampsia and gestational diabetes, which raise later risk

Diagnosis

• History and risk assessment.
• ECG: may be normal at rest; shows changes during ischemia or past heart attacks.
• Blood tests: cholesterol, glucose or HbA1c, kidney function, and troponin if a heart attack is suspected.
• Stress testing: exercise ECG, stress echocardiogram or nuclear perfusion scan to show ischemia during exertion or with medicine.
• CT coronary angiography: a non-invasive scan showing plaque and narrowing; recommended as a first test for many people with chest pain.
• Coronary artery calcium scoring: estimates plaque burden for risk prediction.
• Invasive coronary angiography: dye injected through a catheter shows narrowings precisely, and stents can be placed at the same time.
• Echocardiogram: assesses heart pumping function.

Treatment

Lifestyle

• stop smoking: the single most effective change
• heart-healthy, Mediterranean-style diet
• at least 150 minutes of moderate exercise a week, ideally through cardiac rehabilitation after events
• weight management
• limit alcohol
• manage stress and sleep

Medicines

• Antiplatelets: aspirin; dual antiplatelet therapy after a heart attack or stent
• Statins: high-intensity statins lower LDL and stabilize plaque; ezetimibe or PCSK9 inhibitors if needed
• Anti-angina medicines: beta-blockers, calcium channel blockers, long-acting nitrates and ranolazine
• Nitroglycerin spray or tablets for rapid angina relief
• Blood pressure and diabetes control: ACE inhibitors or ARBs; SGLT2 inhibitors or GLP-1 receptor agonists in people with diabetes
• Heart failure medicines when the heart muscle is weakened

Procedures

• Percutaneous coronary intervention (PCI): balloon angioplasty with a stent to open a narrowed artery. In stable disease, it mainly relieves symptoms; in heart attacks, it saves heart muscle and lives.
• Coronary artery bypass grafting (CABG): uses blood vessels from the chest, arm or leg to route around blockages. Preferred for some patients with widespread disease, left main artery disease or diabetes.

Complications

• heart attack
• heart failure
• arrhythmias, including atrial fibrillation and dangerous ventricular rhythms
• sudden cardiac death
• stroke

Prevention

Primary prevention aims to control risk factors before disease develops: not smoking, healthy diet and weight, regular exercise, and treating high blood pressure, cholesterol and diabetes. Adults should know their numbers and have a cardiovascular risk assessment, typically from age 40 or earlier with risk factors.

Frequently asked questions

What is ischemic heart disease?

Ischemic heart disease is a condition in which the heart muscle does not get enough blood and oxygen, usually because the coronary arteries are narrowed by fatty plaque. It causes angina and can lead to heart attacks and heart failure. It is also called coronary artery disease.

What are the symptoms of ischemic heart disease?

The main symptom is chest pressure, tightness or pain during exertion or stress that eases with rest, sometimes spreading to the arm, jaw or back. Breathlessness, fatigue and nausea are also common. Some people have no symptoms until a heart attack.

Is ischemic heart disease the same as coronary artery disease?

The terms are mostly interchangeable. Coronary artery disease describes narrowing of the coronary arteries, while ischemic heart disease describes the resulting reduced blood flow to the heart muscle, which can also occur from small vessel disease or spasm.

Can ischemic heart disease be reversed?

Plaque usually cannot be removed completely, but intensive treatment with lifestyle changes and high-intensity statins can stabilize and slightly shrink plaque, reduce symptoms and lower the risk of heart attack. Procedures can restore blood flow in narrowed arteries.

What is the life expectancy with ischemic heart disease?

Life expectancy varies widely depending on age, heart function, extent of disease and risk factor control. Many people live for decades with well-managed disease. Stopping smoking, taking prescribed medicines and attending cardiac rehabilitation significantly improve outlook.