Cardiovascular Diseases are disorders affecting the heart, blood vessels and related circulatory structures. They include coronary artery disease, cerebrovascular disease, peripheral arterial disease, heart failure, arrhythmias, valvular disorders, cardiomyopathies, congenital cardiovascular abnormalities and several other conditions. The cardiovascular system transports oxygen, nutrients, hormones and metabolic products while maintaining tissue perfusion and regulating pressure and volume. Cardiovascular disease can be acute or chronic, congenital or acquired, and may involve structural, electrical, inflammatory, infectious, metabolic or vascular mechanisms. The broad category is therefore substantially wider than the commonly used term heart disease.
Atherosclerosis is a major pathological process underlying many Cardiovascular Diseases. It involves accumulation of lipids, inflammatory cells and connective tissue within arterial walls, producing plaques that can narrow vessels or become unstable. Plaque disruption can activate thrombosis and suddenly obstruct blood flow, producing myocardial infarction or ischaemic stroke depending on the vascular territory involved. Low-density lipoprotein cholesterol plays an important causal role in atherosclerotic development, while hypertension, smoking, diabetes and other factors influence overall risk. Atherosclerosis is therefore a chronic vascular process that can remain clinically silent until significant obstruction or an acute vascular event occurs.
Coronary artery disease affects the blood vessels supplying the heart muscle. Stable coronary disease can cause exertional angina when myocardial oxygen demand exceeds supply, while acute coronary syndromes arise from acute changes such as plaque disruption and thrombosis. Myocardial infarction occurs when prolonged ischaemia causes myocardial cell death. Symptoms can include chest discomfort, breathlessness, nausea, sweating or pain radiating to other areas, although presentations vary and some people have atypical or minimal symptoms. Diagnosis can involve electrocardiography, cardiac biomarkers, imaging and assessment of coronary anatomy. Prompt treatment is important because the extent of myocardial injury increases with prolonged ischaemia.
Heart failure occurs when the cardiovascular system cannot maintain adequate circulation without abnormal pressures or compensatory mechanisms. It can result from coronary disease, hypertension, cardiomyopathy, valve disease, arrhythmias and other conditions. Heart failure with reduced ejection fraction is characterised by impaired systolic function, while heart failure with preserved ejection fraction involves impaired filling and increased filling pressures despite relatively preserved ejection fraction. Symptoms can include breathlessness, reduced exercise tolerance, fatigue and fluid retention. Management may involve medications, treatment of underlying causes, lifestyle measures, devices and specialist interventions depending on the phenotype and severity.
Arrhythmias are disorders of cardiac rhythm caused by abnormalities in impulse generation or conduction. Atrial fibrillation produces irregular atrial electrical activity and increases thromboembolic stroke risk, while ventricular tachyarrhythmias can be life-threatening because they can severely impair cardiac output. Bradyarrhythmias can result from conduction-system disease or medication effects and may cause dizziness or syncope. Electrocardiography provides a central method for identifying rhythm abnormalities, although intermittent disorders may require prolonged ambulatory monitoring. Treatment varies from observation and medication to cardioversion, catheter ablation, pacemaker implantation or defibrillator therapy according to the specific rhythm and clinical circumstances.
Cardiovascular risk is influenced by both modifiable and non-modifiable factors. Age, family history and some inherited conditions cannot be changed, whereas smoking, hypertension, diabetes, high LDL cholesterol, physical inactivity and some dietary patterns can be modified. Prevention generally involves managing several risk factors simultaneously rather than focusing on one measurement. Regular physical activity improves cardiovascular fitness and metabolic health, while smoking cessation produces substantial reductions in cardiovascular risk. Blood-pressure control and evidence-based lipid-lowering treatment can reduce vascular events in appropriately selected individuals.
Cardiovascular Diseases have effects far beyond the heart itself. Reduced blood flow can injure the brain, kidneys, intestines and limbs, while chronic heart failure can cause congestion in the lungs and other tissues. Peripheral arterial disease can produce exertional limb pain and indicates systemic atherosclerotic burden. Cardiovascular disease can also interact with kidney disease because each can worsen the other through blood-pressure, fluid and vascular mechanisms. Diabetes accelerates vascular injury, while chronic inflammatory or autoimmune disorders can occasionally affect cardiac or vascular tissues. Cardiovascular medicine consequently incorporates interactions among multiple organ systems.
A common misconception is that Cardiovascular Diseases affect only older men or only people with obesity. They can affect people of all ages, and women can have clinically important cardiovascular disease despite differences in age of presentation and symptom patterns. Another misconception is that a normal resting heart rate proves cardiovascular health; rhythm, blood pressure, vascular structure and coronary disease are not determined by pulse rate alone. Sudden chest pain, severe breathlessness, fainting, new neurological deficits or other acute symptoms can indicate a cardiovascular emergency. Long-term cardiovascular health depends on risk assessment, preventive treatment, recognition of symptoms and management of established disease rather than on one lifestyle metric or isolated test.
