Cardiology is the study of the heart. Cardiology is a branch of medicine that deals with disorders of the heart and the cardiovascular system. The field includes medical diagnosis and treatment of congenital heart defects, coronary artery disease, heart failure, valvular heart disease and electrophysiology. Physicians who specialize in this field of medicine are called cardiologists, a speciality of internal medicine. Pediatric cardiologists are pediatricians who specialize in cardiology. Physicians who specialize in cardiac surgery are called cardiothoracic surgeons or cardiac surgeons, a speciality of general surgery.
Blood pressure (BP) is the pressure of circulating blood against the walls of blood vessels. Most of this pressure results from the heart pumping blood through the circulatory system. When used without qualification, the term "blood pressure" refers to the pressure in the large arteries. Blood pressure is usually expressed in terms of the systolic pressure over diastolic pressure in the cardiac cycle. It is measured in millimeters of mercury (mmHg) above the surrounding atmospheric pressure.
Hypertension, also known as high blood pressure (HBP), is a long-term medical condition in which the blood pressure in the arteries is persistently elevated. High blood pressure usually does not cause symptoms. High blood pressure, however, is a major risk factor for stroke, coronary artery disease, heart failure, atrial fibrillation, peripheral arterial disease, vision loss, chronic kidney disease, and dementia. Hypertension is a major cause of premature death worldwide.
Pulmonary embolism (PE) is a blockage of an artery in the lungs by a substance that has moved from elsewhere in the body through the bloodstream (embolism). Symptoms of a PE may include shortness of breath, chest pain particularly upon breathing in, and coughing up blood. Symptoms of a blood clot in the leg may also be present, such as a red, warm, swollen, and painful leg. Signs of a PE include low blood oxygen levels, rapid breathing, rapid heart rate, and sometimes a mild fever. Severe cases can lead to passing out, abnormally low blood pressure, obstructive shock, and sudden death.
Heart failure (HF), also known as congestive heart failure (CHF), is a syndrome, a group of signs and symptoms, caused by an impairment of the heart's blood pumping function. Symptoms typically include shortness of breath, excessive fatigue, and leg swelling. The shortness of breath may occur with exertion or while lying down, and may wake people up during the night. Chest pain, including angina, is not usually caused by heart failure, but may occur if the heart failure was caused by a heart attack. The severity of the heart failure is mainly decided based on ejection fraction and also measured by the severity of symptoms. Other conditions that may have symptoms similar to heart failure include obesity, kidney failure, liver disease, anemia, and thyroid disease.
Pulmonary heart disease, also known as cor pulmonale, is the enlargement and failure of the right ventricle of the heart as a response to increased vascular resistance or high blood pressure in the lungs.
Pulmonary edema, also known as pulmonary congestion, is excessive liquid accumulation in the tissue and air spaces of the lungs. It leads to impaired gas exchange and may cause hypoxemia and respiratory failure. It is due to either failure of the left ventricle of the heart to remove oxygenated blood adequately from the pulmonary circulation, or an injury to the lung tissue directly or blood vessels of the lung.
A pulmonary artery is an artery in the pulmonary circulation that carries deoxygenated blood from the right side of the heart to the lungs. The largest pulmonary artery is the main pulmonary artery or pulmonary trunk from the heart, and the smallest ones are the arterioles, which lead to the capillaries that surround the pulmonary alveoli.
Pulmonary hypertension is a condition of increased blood pressure in the arteries of the lungs. Symptoms include shortness of breath, fainting, tiredness, chest pain, swelling of the legs, and a fast heartbeat. The condition may make it difficult to exercise. Onset is typically gradual.
The Fontan procedure or Fontan–Kreutzer procedure is a palliative surgical procedure used in children with univentricular hearts. It involves diverting the venous blood from the inferior vena cava (IVC) and superior vena cava (SVC) to the pulmonary arteries. The procedure varies for differing congenital heart pathologies. For example in tricuspid atresia, the procedure can be done where the blood does not pass through the morphologic right ventricle; i.e., the systemic and pulmonary circulations are placed in series with the functional single ventricle. Whereas in hypoplastic left heart syndrome, the heart is more reliant on the more functional right ventricle to provide blood flow to the systemic circulation. The procedure was initially performed in 1968 by Francis Fontan and Eugene Baudet from Bordeaux, France, published in 1971, simultaneously described in 1971 by Guillermo Kreutzer from Buenos Aires, Argentina, and finally published in 1973.
Eisenmenger syndrome or Eisenmenger's syndrome is defined as the process in which a long-standing left-to-right cardiac shunt caused by a congenital heart defect causes pulmonary hypertension and eventual reversal of the shunt into a cyanotic right-to-left shunt. Because of the advent of fetal screening with echocardiography early in life, the incidence of heart defects progressing to Eisenmenger syndrome has decreased.
Cardiac catheterization is the insertion of a catheter into a chamber or vessel of the heart. This is done both for diagnostic and interventional purposes.
Endothelins are peptides with receptors and effects in many body organs. Endothelin constricts blood vessels and raises blood pressure. The endothelins are normally kept in balance by other mechanisms, but when overexpressed, they contribute to high blood pressure (hypertension), heart disease, and potentially other diseases.
A hypertensive emergency is very high blood pressure with potentially life-threatening symptoms and signs of acute damage to one or more organ systems. It is different from a hypertensive urgency by this additional evidence for impending irreversible hypertension-mediated organ damage (HMOD). Blood pressure is often above 200/120 mmHg, however there are no universally accepted cutoff values. Signs of organ damage are discussed below.
Hypertensive heart disease includes a number of complications of high blood pressure that affect the heart. While there are several definitions of hypertensive heart disease in the medical literature, the term is most widely used in the context of the International Classification of Diseases (ICD) coding categories. The definition includes heart failure and other cardiac complications of hypertension when a causal relationship between the heart disease and hypertension is stated or implied on the death certificate. In 2013 hypertensive heart disease resulted in 1.07 million deaths as compared with 630,000 deaths in 1990.
Vascular disease is a class of diseases of the vessels of the circulatory system in the body, including blood vessels – the arteries and veins, and the lymphatic vessels. Vascular disease is a subgroup of cardiovascular disease. Disorders in this vast network of blood and lymph vessels can cause a range of health problems that can sometimes become severe, and fatal. Coronary heart disease for example, is the leading cause of death for men and women in the United States.
The DASH diet is a dietary pattern promoted by the U.S.-based National Heart, Lung, and Blood Institute to prevent and control hypertension. The DASH diet is rich in fruits, vegetables, whole grains, and low-fat dairy foods. It includes meat, fish, poultry, nuts, and beans, and is limited in sugar-sweetened foods and beverages, red meat, and added fats. In addition to its effect on blood pressure, it is designed to be a well-balanced approach to eating for the general public. DASH is recommended by the United States Department of Agriculture (USDA) as a healthy eating plan. The DASH diet is one of three healthy diets recommended in the 2015–2020 US Dietary Guidelines, which also include the Mediterranean diet and a vegetarian diet. The American Heart Association (AHA) considers the DASH diet "specific and well-documented across age, sex and ethnically diverse groups."
Persistent fetal circulation is a condition caused by a failure in the systemic circulation and pulmonary circulation to convert from the antenatal circulation pattern to the "normal" pattern. Infants experience a high mean arterial pulmonary artery pressure and a high afterload at the right ventricle. This means that the heart is working against higher pressures, which makes it more difficult for the heart to pump blood.
Jason X.-J. Yuan is an American physician scientist whose research interests center on pulmonary vascular pathobiology and pulmonary hypertension. His current research is primarily focused on the pathogenic mechanisms of pulmonary vascular diseases and right heart failure.
Rhian M. Touyz Koppel MBBCh, MSc (Med), PhD, FRCP, FRSE, FMedSci, FCAHS is a Canadian medical researcher. She is currently serving as the Executive Director and Chief Scientific Officer of the Research Institute of the McGill University Health Centre in Montreal, Canada, since 2021. A clinician scientist, her research primarily focuses on hypertension and cardiovascular disease.
