Artificial heart valve

prosthetic heart valveartificial heart valvesmechanical heart valve
This requires open-heart surgery. Heart valves are integral to the normal physiological functioning of the human heart. Natural heart valves induce unidirectional blood flow through the valve structure from one chamber of the heart to another. Natural heart valves become dysfunctional for a variety of pathological causes, some of which may require complete surgical replacement of the natural heart valve with an artificial valve. There are three main types of artificial heart valves: the mechanical,the biological, and the tissue engineered valves. Mechanical heart valves (MHV) are prosthetics designed to replicate the function of the natural valves of the human heart.

Surgery

surgicalsurgeonsurgical procedure
Examples include cardiac surgery (performed on the heart), gastrointestinal surgery (performed within the digestive tract and its accessory organs), and orthopedic surgery (performed on bones or muscles). By degree of invasiveness of surgical procedures: Minimally-invasive surgery involves smaller outer incision(s) to insert miniaturized instruments within a body cavity or structure, as in laparoscopic surgery or angioplasty. By contrast, an open surgical procedure such as a laparotomy requires a large incision to access the area of interest. By equipment used: Laser surgery involves use of a laser for cutting tissue instead of a scalpel or similar surgical instruments.

Endothelium

endothelialendothelial cellsendothelial cell
Endothelial cells are involved in many aspects of vascular biology, including: Endothelial dysfunction, or the loss of proper endothelial function, is a hallmark for vascular diseases, and is often regarded as a key early event in the development of atherosclerosis. Impaired endothelial function, causing hypertension and thrombosis, is often seen in patients with coronary artery disease, diabetes mellitus, hypertension, hypercholesterolemia, as well as in smokers. Endothelial dysfunction has also been shown to be predictive of future adverse cardiovascular events, and is also present in inflammatory disease such as rheumatoid arthritis and systemic lupus erythematosus.

Smooth muscle

smooth muscle cellssmooth musclessmooth muscle cell
Activation of aortic smooth muscle doesn't significantly alter the lumenal diameter but serves to increase the viscoelasticity of the vascular wall. In the digestive tract, smooth muscle contracts in a rhythmic peristaltic fashion, rhythmically forcing foodstuffs through the digestive tract as the result of phasic contraction. A non-contractile function is seen in specialized smooth muscle within the afferent arteriole of the juxtaglomerular apparatus, which secretes renin in response to osmotic and pressure changes, and also it is believed to secrete ATP in tubuloglomerular regulation of glomerular filtration rate.

Cardiac muscle

myocardiumheart musclemyocardial
These originate from the aortic root and lie on the outer or epicardial surface of the heart. Blood is then drained away by the coronary veins into the right atrium. When looked at microscopically, cardiac muscle can be likened to the wall of a house. Most of the wall is taken up by bricks, which in cardiac muscle are individual cardiac muscle cells or cardiomyocytes. The mortar which surrounds the bricks is known as the extracellular matrix, produced by supporting cells known as fibroblasts.

Cholesterol

serum cholesteroldietary cholesterolcholesterol level
Elevated levels of the lipoprotein fractions, LDL, IDL and VLDL are regarded as atherogenic (prone to cause atherosclerosis). Levels of these fractions, rather than the total cholesterol level, correlate with the extent and progress of atherosclerosis. Conversely, the total cholesterol can be within normal limits, yet be made up primarily of small LDL and small HDL particles, under which conditions atheroma growth rates would still be high.

Coronary circulation

coronary arteriescoronarycoronary artery
Anomalous aortic origin of a coronary artery.

Atheroma

atherosclerotic plaqueplaqueatheromatous plaque
Atherosclerosis. Atherothrombosis. Coronary circulation. Coronary catheterization. EBT. Hemorheologic-Hemodynamic Theory of Atherosclerosis. Lipoprotein. LDL, HDL, IDL and VLDL.

Carotid endarterectomy

carotid endarterectomiesendarterectomy, carotidsurgery to open up the arteries to the brain
Need for open heart surgery within 30 days. Left ventricular ejection fraction of ≤30%. Recent (≤30-day) heart attack. Severe lung disease or COPD. Severe renal disease. High cervical (C2) or intrathoracic lesion. Prior radical neck surgery or radiation therapy. Contralateral carotid artery occlusion. Prior ipsilateral CEA. Contralateral laryngeal nerve injury. Tracheostoma.

Cardiovascular disease

heart diseasecardiac diseaseheart condition
Recent areas of research include the link between inflammation and atherosclerosis the potential for novel therapeutic interventions, and the genetics of coronary heart disease. Coronary artery disease (also known as coronary heart disease and ischemic heart disease). Peripheral arterial disease – disease of blood vessels that supply blood to the arms and legs. Cerebrovascular disease – disease of blood vessels that supply blood to the brain (includes stroke). Renal artery stenosis. Aortic aneurysm. Cardiomyopathy – diseases of cardiac muscle. Hypertensive heart disease – diseases of the heart secondary to high blood pressure or hypertension.

Russell Brock, Baron Brock

Russell BrockRussell Claude BrockLord Brock
Russell Claude Brock, Baron Brock (24 October 1903 – 3 September 1980) was a leading British chest and heart surgeon and one of the pioneers of modern open-heart surgery. His achievements were recognised by a Knighthood in 1954, a Life Peerage in 1965, and a host of other awards. He was born in London, 1903, the son of Herbert Brock, a master photographer, and his wife, Elvina (née Carman). He was the second of six sons and fourth of eight children. He was educated at Haselrigge Road School, Clapham, and then at Christ's Hospital, Horsham, where he later became an Almoner (governor). He entered Guy's Hospital Medical School in 1921 at age 17 with an arts scholarship.

Heyde's syndrome

multiple colonic angiodysplasiae
The exact prevalence of the syndrome is unknown, because both aortic stenosis and angiodysplasia are common diseases in the elderly. A retrospective chart review of 3.8 million people in Northern Ireland found that the incidence of gastrointestinal bleeding in people with any diagnosis of aortic stenosis (they did not subgroup people by severity) was just 0.9%. They also found that the reverse correlation—the incidence of aortic stenosis in people with gastrointestinal bleeding—was 1.5%.

Vulnerable plaque

plaque ruptureplaque rupturesobviously symptomatic
Repeated atheroma rupture and healing is one of the mechanisms, perhaps the dominant one, that creates artery stenosis. Researchers have found that accumulation of white blood cells, especially macrophages, termed inflammation, in the walls of the arteries leads to the development of "soft" or vulnerable plaque, which when released aggressively promotes blood clotting.

Renovascular hypertension

hypertension, renovascularRenal hypertension
Those with atherosclerotic renal artery disease have a high risk of mortality, furthermore those who also have renal dysfunction have a higher mortality risk. However, the majority of renovascular diseases can be improved with surgery. * High blood pressure (early age). Kidney dysfunction. Narrowing of arteries elsewhere in the body. Pulmonary edema. Blood test (for renal function). Urinary test (tests for microalbuminuria). Serology (to exclude systemic lupus erythematosus ). Lipid profile. Urinalysis (to exclude presence of red blood cells). Fibromuscular dysplasia. Hypertensive nephropathy. Kidney failure. Renal artery stenosis.

Elastin

tropoelastinELNelastic
Deletions and mutations in this gene are associated with supravalvular aortic stenosis (SVAS) and the autosomal dominant cutis laxa. Other associated defects in elastin include Marfan syndrome, emphysema caused by α 1 -antitrypsin deficiency, atherosclerosis, Buschke-Ollendorff syndrome, Menkes syndrome, pseudoxanthoma elasticum, and Williams syndrome. In the body, elastin is usually associated with other proteins in connective tissues. Elastic fiber in the body is a mixture of amorphous elastin and fibrous fibrillin. Both components are primarily made of smaller amino acids such as glycine, valine, alanine, and proline.

Renal artery

renal arteriesrenalarteries of the kidneys
Renal artery stenosis, or narrowing of one or both renal arteries will lead to hypertension as the affected kidneys release renin to increase blood pressure to preserve perfusion to the kidneys. RAS is typically diagnosed with duplex ultrasonography of the renal arteries. It is treated with the use of balloon angioplasty and stents, if necessary.

Arteriole

arteriolesarteriolararterial
Any pathology which constricts blood flow, such as stenosis, will increase total peripheral resistance and lead to hypertension. Arteriolosclerosis is the term specifically used for the hardening of arteriole walls. This can be due to decreased elastic production from fibrinogen, associated with ageing, or hypertension or pathological conditions such as atherosclerosis. The muscular contraction of arterioles is targeted by drugs that lower blood pressure (antihypertensives), for example the dihydropyridines (nifedipine and nicardipine), which block the calcium conductance in the muscular layer of the arterioles, causing relaxation.

Transient ischemic attack

transient ischaemic attacktransient ischemic attacksmini-stroke
Echocardiography can be performed to identify patent foramen ovale (PFO), valvular stenosis, and atherosclerosis of the aortic arch that could be sources of clots causing TIAs, with transesophageal echocardiography being more sensitive than transthoracic echocardiography in identifying these lesions. Prolonged cardiac rhythm monitoring can be considered to rule out arrhythmias like paroxysmal atrial fibrillation that may lead to clot formation and TIAs, however this should be considered if other causes of TIA have not been found.

Percutaneous aortic valve replacement

transcatheter aortic valve replacementtranscatheter aortic valve implantationpercutaneious transapical TAVI
Percutaneous aortic valve replacement (PAVR), also known as transcatheter aortic valve implantation (TAVI) or transcatheter aortic valve replacement (TAVR), is the replacement of the aortic valve of the heart through the blood vessels (as opposed to valve replacement by open heart surgery). The replacement valve is delivered via one of several access methods: transfemoral (in the upper leg), transapical (through the wall of the heart), subclavian (beneath the collar bone), direct aortic (through a minimally invasive surgical incision into the aorta), and transcaval (from a temporary hole in the aorta near the belly button through a vein in the upper leg), among others.

Pulse

pulse ratepulsationheartbeat
It's an unusual physical finding typically seen in patients with aortic valve diseases if the aortic valve does not normally open and close. Trained fingertips will observe two pulses to each heartbeat instead of one. Pulsus tardus et parvus, also pulsus parvus et tardus, slow-rising pulse and anacrotic pulse, is weak (parvus), and late (tardus) relative to its expected characteristics. It is caused by a stiffened aortic valve that makes it progressively harder to open, thus requiring increased generation of blood pressure in the left ventricle. It is seen in aortic valve stenosis.

Horace Smithy

In June 1948, Smithy sent Blalock a letter indicating that he had a young man from New York whose aortic stenosis was nearly identical to Smithy's. He wrote that the patient was willing to travel to Baltimore for surgery. Smithy came to Baltimore and did laboratory work with technician Vivien Thomas and resident Denton Cooley. When Smithy and Blalock operated on their first patient together, things did not go as they had hoped. The events have been described with slight variations, but it seems that the patient developed a fatal arrhythmia as soon as Cooley made a chest incision and opened the pericardial sac.

Drug-eluting stent

drug eluting stentdrug-eluting stentsdrug-eluting
With PCI, the requirement for emergency CABG has markedly decreased since the days of balloon angioplasty, such that in some communities, coronary stenting is permitted in hospitals without on-site cardiac surgery facilities, though this remains highly controversial in the United States, not the least because of the rare but largely unpredictable risk of coronary artery perforation. Rarely, a type of allergic reaction to the drug may occur; episodes of fatality have been reported.

Heart sounds

heartbeatheart soundsecond heart sound
Stenosis of the aortic valve is typically the next most common heart murmur, a systolic ejection murmur. This is more common in older adults or in those individuals having a two-leaflet, not a three-leaflet, aortic valve. Regurgitation through the aortic valve, if marked, is sometimes audible to a practiced ear with a high quality, especially electronically amplified, stethoscope. Generally, this is a very rarely heard murmur, even though aortic valve regurgitation is not so rare. Aortic regurgitation, though obvious using echocardiography visualization, usually does not produce an audible murmur.

Intravascular ultrasound

IVUSIntravascular ultrasound systemsultrasound
In the early 1990s, IVUS research on the re-stenosis problem after angioplasty lead to recognition that most of the re-stenosis problem (as visualized by an angiography examination) was not true re-stenosis. Instead it was simply a remodeling of the atheromatous plaque, which was still protruding into the lumen of the artery after completion of angioplasty; the stenosis only appearing to be reduced because blood and contrast could now flow around and through some of the plaque. The angiographic dye column appeared widened adequately; yet considerable plaque was within the newly widened lumen and the lumen remained partially obstructed.

Hypertrophic cardiomyopathy

hypertrophic obstructive cardiomyopathyAsymmetric septal hypertrophyHCM
In normal individuals, during ventricular systole, the pressure in the ascending aorta and the left ventricle will equalize, and the aortic valve is open. In individuals with aortic stenosis or with HCM with an outflow tract gradient, there will be a pressure gradient (difference) between the left ventricle and the aorta, with the left ventricular pressure higher than the aortic pressure. This gradient represents the degree of obstruction that has to be overcome in order to eject blood from the left ventricle. The Brockenbrough–Braunwald–Morrow sign is observed in individuals with HCM with outflow tract gradient. This sign can be used to differentiate HCM from aortic stenosis.