Cardiovascular diseases are a group of disorders affecting the heart and blood vessels. They are the leading cause of death worldwide, responsible for 19.2 million deaths in 2023 alone, with roughly 626 million people living with some form of CVD globally. The term is an umbrella that covers several distinct conditions, from blocked arteries feeding the heart to structural defects present at birth.
Types of Cardiovascular Disease
The major cardiovascular diseases fall into six broad categories:
- Coronary heart disease: narrowing or blockage of the arteries that supply blood to the heart muscle itself.
- Cerebrovascular disease: disease of the blood vessels supplying the brain, most commonly stroke.
- Peripheral arterial disease: narrowed arteries reducing blood flow to the arms and legs.
- Rheumatic heart disease: damage to the heart muscle and valves caused by rheumatic fever, which starts as a bacterial throat infection.
- Congenital heart disease: structural defects in the heart that are present from birth.
- Deep vein thrombosis and pulmonary embolism: blood clots that form in the leg veins and can travel to the heart or lungs.
Most cardiovascular deaths are caused by coronary heart disease and stroke. The other conditions are less common but still affect millions of people.
How Artery Disease Develops
The biological engine behind coronary heart disease, most strokes, and peripheral artery disease is the same process: atherosclerosis. It starts when the inner lining of an artery gets damaged, often from high blood pressure, smoking, or high cholesterol. That damage makes the artery wall more permeable, allowing cholesterol particles (LDL) to seep into the vessel wall.
Once trapped inside, those cholesterol particles become oxidized, which triggers an inflammatory response. White blood cells rush to the area and begin absorbing the oxidized cholesterol, swelling into what researchers call “foam cells.” Over time, smooth muscle cells migrate into the area and build a fibrous cap over a growing core of dead cells and fat. This is a plaque.
A stable plaque can narrow an artery for years, gradually restricting blood flow and causing symptoms like chest pain during exertion. The real danger comes when a plaque becomes unstable, with a thin cap and a large, inflamed core. If it ruptures, the body forms a blood clot at the site. That clot can partially or completely block the artery, cutting off blood supply to the heart (heart attack) or brain (stroke) within minutes.
Coronary Heart Disease
Coronary heart disease is the most common cardiovascular disease. The hallmark symptom is angina, a pressure or discomfort behind the breastbone that can spread to the left arm, neck, jaw, or teeth. Physical activity or emotional stress typically triggers stable angina, while unstable angina can strike even at rest and signals a more urgent problem.
Not everyone experiences classic chest pain. Women more often report shortness of breath, unusual fatigue, and back pain. Some people feel what seems like indigestion or a burning sensation in the upper abdomen. In some cases, the only symptom during a cardiac event is pain in the jaw or face. Shortness of breath, nausea, and dizziness are also common.
Doctors use several tools to evaluate coronary heart disease. An electrocardiogram (ECG) can detect abnormal heart rhythms and signs of reduced blood flow. Stress tests push the heart to work harder, revealing problems that don’t show up at rest. A coronary calcium score, which measures calcium buildup in the arteries using a CT scan, is useful for screening: a score of zero rules out significant blockage in over 98% of cases. Cardiac catheterization, where a thin tube is threaded into the heart’s arteries and dye is injected to create detailed images, remains the most accurate way to assess blockage severity.
Stroke
About 85% of strokes are ischemic, meaning a blocked artery cuts off blood to part of the brain. The blockage is usually a clot, often formed by the same atherosclerosis process that causes heart attacks. The remaining 15% are hemorrhagic strokes, where a blood vessel in the brain leaks or bursts. The escaping blood increases pressure on surrounding brain cells and damages them.
Stroke symptoms appear suddenly. The key warning signs include numbness or weakness on one side of the body, trouble speaking or understanding speech, vision problems in one or both eyes, difficulty walking or a loss of balance, and a sudden severe headache. One side of the face may droop when trying to smile. These symptoms are a medical emergency because brain tissue dies quickly without blood flow, and treatment within the first few hours dramatically improves outcomes.
Heart Failure
Heart failure doesn’t mean the heart stops beating. It means the heart can no longer pump blood efficiently enough to meet the body’s needs. It often develops after other cardiovascular damage, such as a heart attack or years of uncontrolled high blood pressure, weakens the heart muscle.
Doctors classify heart failure based on how well the heart pumps with each beat, measured as ejection fraction. A normal heart pushes out about 50% or more of the blood in its main chamber with each contraction. Heart failure with reduced ejection fraction means the heart pumps less than 40%, so it’s significantly weakened. Heart failure with preserved ejection fraction means the heart still pumps 50% or more, but the muscle has become stiff and doesn’t fill properly between beats. A middle category, with ejection fraction between 40% and 49%, is also recognized. The distinction matters because these subtypes respond differently to treatment.
Peripheral Artery Disease
Peripheral artery disease (PAD) narrows the arteries supplying the legs and, less commonly, the arms. The most recognizable symptom is claudication: cramping or aching in the legs during walking that goes away with rest. As the disease progresses, pain can occur even at rest, and wounds on the feet or legs may heal very slowly or not at all.
PAD is diagnosed with a simple, painless test called the ankle-brachial index (ABI), which compares blood pressure at the ankle to blood pressure in the arm. A healthy result is 1.00 or greater. An ABI below 0.90 indicates PAD, and a reading below 0.40 signals severe disease. PAD is also an important warning sign: people with narrowed leg arteries are at higher risk for heart attack and stroke because the same atherosclerosis process is likely affecting arteries elsewhere in the body.
Congenital Heart Disease
Congenital heart defects are structural problems with the heart that form before birth. They range from small holes between heart chambers that may close on their own to complex defects that require surgery in the first days of life. The most common defects include holes in the wall between the upper chambers (atrial septal defects) or lower chambers (ventricular septal defects), an abnormal connection between two major blood vessels (patent ductus arteriosus), and Tetralogy of Fallot, the most common defect that causes low oxygen levels in the blood.
Most congenital heart defects are first detected when a doctor hears an abnormal heart murmur during a routine exam or when a newborn fails a pulse oximetry screening, which measures oxygen levels through a small sensor on the foot. Ultrasound imaging of the heart (echocardiogram) confirms the diagnosis. Some defects are now identified before birth through prenatal ultrasound, though this accounts for a small fraction of cases.
Major Risk Factors
High blood pressure is the single largest risk factor for cardiovascular disease. The 2025 guidelines from the American Heart Association define normal blood pressure as below 120/80 mmHg. Elevated blood pressure starts at 120-129 systolic (the top number) with a bottom number still below 80. Stage 1 hypertension is 130-139 systolic or 80-89 diastolic. Stage 2 hypertension, which carries the highest risk, is 140 or above systolic or 90 or above diastolic. High blood pressure damages artery walls over time, accelerating the atherosclerosis process.
Other major risk factors include high LDL cholesterol, smoking, diabetes, obesity, physical inactivity, and a family history of heart disease. Smoking roughly doubles the risk of cardiovascular events and directly damages the lining of blood vessels. Diabetes accelerates plaque formation and makes plaques more prone to rupture. These risk factors compound each other: having two or three simultaneously raises your risk far more than each one would individually.
Prevention Through Lifestyle
The majority of cardiovascular disease is preventable through lifestyle changes. The American Heart Association recommends at least 150 minutes per week of moderate-intensity aerobic activity (like brisk walking) or 75 minutes of vigorous activity (like running), ideally spread throughout the week rather than packed into one or two sessions. Adding strength training on at least two days per week provides additional benefit, and people who reach 300 minutes of weekly activity see even greater protection.
Beyond exercise, the most impactful changes are quitting smoking, maintaining a healthy weight, managing blood pressure and cholesterol, and eating a diet rich in vegetables, fruits, whole grains, and lean protein while limiting processed foods, added sugars, and sodium. For people who already have risk factors, medications to control blood pressure or cholesterol can significantly reduce the chance of a first heart attack or stroke. The earlier these risk factors are identified and managed, the more effective prevention becomes.