idiopathic hypertrophic subaortic stenosis


Also found in: Dictionary, Thesaurus, Acronyms, Encyclopedia.

stenosis

 [stĕ-no´sis] (pl. steno´ses)
an abnormal narrowing or contraction of a body passage or opening; called also arctation, coarctation, and stricture.
aortic stenosis obstruction to the outflow of blood from the left ventricle into the aorta; in the majority of adult cases the etiology is degenerative calcific disease of the valve.
hypertrophic subaortic stenosis (idiopathic hypertrophic subaortic stenosis) a cardiomyopathy of unknown cause, in which the left ventricle is hypertrophied and the cavity is small; it is marked by obstruction to left ventricular outflow.
mitral stenosis a narrowing of the left atrioventricular orifice (mitral valve) due to inflammation and scarring; the cause is almost always rheumatic heart disease. Normally the leaflets open with each pulsation of the heart, allowing blood to flow from the left atrium into the left ventricle, and close as the ventricle fills again so that they prevent a backward flow of blood. In mitral stenosis there is a resultant increase of pressure in the pulmonary artery and hypertrophy of the left ventricle. The usual treatment is surgical replacement of the valve.
pulmonary stenosis (PS) narrowing of the opening between the pulmonary artery and the right ventricle.
pyloric stenosis see pyloric stenosis.
renal artery stenosis narrowing of one or both renal arteries by atherosclerosis or by fibrous dysplasia or hyperplasia, so that renal function is impaired (see ischemic nephropathy). Increased renin release by the affected kidney causes renovascular hypertension, and bilateral stenosis may result in chronic renal failure.
spinal stenosis narrowing of the vertebral canal, nerve root canals, or intervertebral foramina of the lumbar spine, caused by encroachment of bone upon the space; symptoms are caused by compression of the cauda equina and include pain, paresthesias, and neurogenic claudication. The condition may be either congenital or due to spinal degeneration.
subaortic stenosis aortic stenosis due to an obstructive lesion in the left ventricle below the aortic valve, causing a pressure gradient across the obstruction within the ventricle. See also idiopathic hypertrophic subaortic stenosis.
subglottic stenosis stenosis of the trachea below the glottis. A congenital form results in neonatal stridor or laryngotracheitis, often requiring tracheotomy but resolving with age. An acquired form is caused by repeated intubations.
tracheal stenosis scarring of the trachea with narrowing, usually as a result of injury from an artificial airway or trauma.
tricuspid stenosis (TS) narrowing or stricture of the tricuspid orifice of the heart, a condition often seen in patients with severe congestive heart failure, usually the result of volume overload and pulmonary hypertension with right ventricular and tricuspid annular dilation.

asymmetric septal hypertrophy (ASH),

abnormal enlargement, congenital or acquired, of the left ventricular side of the septum under the aortic valve causing outflow obstruction and abnormal movement of the mitral valve.
See also: systolic anterior motion.

hypertrophic cardiomyopathy

A common (1:500) condition which causes a range of mild to severe clinical and pathologic changes, which are either symmetrical (concentric) or asymmetrical (eccentric hypertrophy), with disproportionate thickening beneath the mitral valve, seen without other cardiac disease. Half are congenital with autosomal dominant patterns of inheritance—e.g., MIM 192600, MIM 160760. Obstruction is associated with reduced venous return.

Clinical findings, young patients
Range from asymptomatic to diastolic dysfunction, dyspnea, fatigue, anginal pain, syncope, an increased risk of severe obstruction, congestive heart failure, sudden death simulating acute myocardial infarction.

Clinical findings, older patients
Shortness of breath, anginal pain, syncope.

EKG Increased
QRS complexes, T-wave inversion, Q waves in inferior and left-precordial leads—which translate into asymmetric hypertrophy of the septum (usually of left side), systolic anterior movement of mitral valve, and midsystolic closure of aortic valve.

Adverse associations
Ethanol in patients with HC increases systolic blood pressure, and the pressure gradient across left ventricular outflow tract.

Management
• Symptomatic—i.e., relief of dyspnoea or chest pain.
• Drugs—beta-adrenergics are effective short-term, calcium channel blockers (which increase diastolic ventricular filling) may be effective long-term.
• Surgery—recalcitrant cases may need a transaortic ventricular septal myotomy-myectomy.

idiopathic hypertrophic subaortic stenosis

Hypertrophic cardiomyopathy, see there.

id·i·o·path·ic hy·per·tro·phic su·ba·or·tic ste·no·sis

(id'ē-ō-path'ik hī'pĕr-trō'fik sŭb'ā-ōr'tik stĕ-nō'sis)
Left ventricular outflow obstruction due to hypertrophy, usually congenital, of the ventricular septum.
Medical browser ?
Full browser ?