Cardiology

Cardiovascular diseases are a common cause of mortality and morbidity worldwide. Co-incidentally cardiology is also one of the most exciting branches of medicine.  It is also rapidly changing specialty with new imaging modalities and therapeutic advances through the advent of interventional techniques such as angiography, stenting, pacing and electrophysiology techniques.

There are a huge number of systemic disease processes that can affect the heart muscles, blood supply and pericardium ranging from malignancy to infection. In the Western world, atherosclerosis causing ischaemic heart disease is the most common problem, but this is becoming an increasing problem in developing countries.  Infective problems such as endocarditis and severe valvular dysfunction continue to be common in the developing world. Universally, heart disease is a very common cause of morbidity and mortality and is an important topic for any generalist.

Clinical evaluation of a patient with cardiovascular disease

A good thorough cardiovascular examination can reveal lots of important information about the underlying pathology. Whilst examination is undoubtedly best taught at the bedside with real patients, technology is making it possible for some of techniques and skills to be learned using online resources – including videos and audio files.

Understanding the electrocardiogram

An electrocardiogram (ECG or EKG) is a non-invasive recording of the electrical activity of the heart over a period of time. It is a useful tool for the diagnosis of almost all cardiac disorders and despite modern imaging techniques remains at the forefront of acute cardiology. Interpretation of ECG is a skill that needs to be learned by all young doctors and there are many good online resources here to help.

Cardiac imaging

Cardiac imaging is one of the fastest growing areas of clinical cardiology. Whilst the Echocardiogram is currently the mainstay for assessment of cardiac structure and function, MRI and nuclear imaging look set to have a major role in the future.

Disorders of heart rhythm

Coronary heart disease

Coronary heart disease (CHD) is caused by a build up in atheroma in the cells lining the wall of the coronary arteries. This causes a narrowing in the blood vessel limiting the blood (and oxygen) supply to the heart muscle. If a severe blockage occurs  quickly (often as a result of a superimposed blood clot) then a heart attack can occur. A more gradual narrowing results in the clinical syndrome of angina.

In the Western world , cardiovascular disease is the leading cause of death among both sexes, and coronary artery disease is the commonest cause of cardiovascular disease. A number of preventable risk factors lead to coronary heart disease namely high blood pressure (hypertension), high cholesterol, diabetes, a sedentary lifestyle and smoking. The rising epidemic of obesity and associated metabolic syndrome (hypertension, insulin resistance and hypercholesterolaemia) is increasing the incidence of heart disease.

Treatments to tackle coronary heart disease are aimed at prevention, symptom control and revascularisation either using drugs, newer interventional techniques such as angioplasty and stenting or surgery (coronary artery bypass grafting).

Heart failure and cardiomyopathy

Heart Failure occurs when the pumping action of the heart is unable to meet the bodies demands resulting in reduced blood and oxygen deliver to peripheral organs and tissues. Fatigue and breathlessnes are common and fluid accumulation in the lungs (pulmonary oedema) and legs (peripheral oedema) are characteristic signs of heart failure. Heart failure can occur as a result of any of the conditions discussed above (ischaemic heart disease, valvular heart disease, cardiomyopathies, pericardial disease etc.). The mainstay of treatment is medication (aimed at diuresing and lowering peripheral resistance), although pacing devices and heart transplant may be considered in some cases.

Cardiomyopathy is a collective term for diseases affecting the muscle of the heart. The common intrinsic cardiomyopathies include hypertrophic (HOCM), restrictive and dilated. Other recognised types include arrhythmogenic right ventricular cardiomyopathy (ARVC) and noncompaction cardiomyopathy. Cardiomyopathies may be congenital, occur as a result of systemic diseases such as amyloidosis, or secondary to toxins including alcohol. Treatment is challenging and may include medication, pacemakers, ventricular assist devices or ablation. The goal of treatment is symptom relief and some patients may ultimately requires a heart transplant.

Adult congenital heart disease

Congenital heart disease consists of any cardiac abnormality that is present from birth. This may range form an abnormality in the hearts rhythm such as long QT syndrome through to more major defects of the heart chambers and major blood vessels. Heart defects are the most common cause of birth defects (approx 9 in 1000 people are born with congenital heart problem). Most of these are due to sporadic genetic changes although some are due to environmental factors such as infections (e.g. Rubella), toxins such as alcohol, prescription drugs and diseases such as diabetes and SLE.

Valvular heart disease

The heart has 4 valves (two of the right side of the heart (the Tricuspid and Pulmonary) and two on the Left Side of the heart (Mitral and Aortic). Valve abnormalities may be congenital (occur during development) or acquired later in life due to processes such as rheumatic fever and infection. It is possible to replace heart valves surgically in selected patients.

Pericardial disease

The pericardium is a double walled sac surrounding the heart and the great vessels which can be affected by a number of disease processes. Fluid or blood accumulation in the pericardial space can lead to effusions which may impact on cardiac function. Malignancy, renal failure, viruses and systemic diseases such as amyloidosis can lead to pericardial inflammation or scarring.

Cardiology interventions and therapeutics

This sections covers therapeutics from pharmacological therapies to interventional techniques. This is a rapidly growing area of cardiology. Many of the new and novel procedures are discusses below.

Clinical case scenarios and self assessment

Here is a collection of resources containing virtual patients and clinical case scenarios. These are excellent for problem based learning and for improving clinical insight. There are also self-assessment materials, useful for exam practice.

Section editors

Dr Nikhil Joshi, Clinical Research Fellow in Cardiology, University of Edinburgh

Dr Alka Joshi, Core Medical Trainee, Royal Infirmary of Edinburgh

Adam Melville, 4th Year Medical Student, University of Edinburgh