Subvalvular aortic stenosis is an abnormality of the subaortic region currently classified as a non-cyanotic congenital heart malformation that causes the partial obstruction of the left ventricle outflow tract. This condition has a progressive and recurrent character.
Subvalvular aortic stenosis is more frequently seen in males  and may be asymptomatic during the early childhood. In this case, it is incidentally discovered during a heart murmur evaluation . Symptoms tend to occur as the patient grows older  and the lesion becomes more severe. Initially, the patient comes with complaints that only install during physical efforts, such as dyspnea, dizziness, presyncope or angina with normal coronary arteries. In more advanced stages, veritable syncope is caused by less intense effort. Additional complaints include orthopnea and other heart failure manifestations. Sudden cardiac death may be the first sign of disease. Orthopnea may signify the presence of pulmonary venous hypertension, while syncope may be due to an arrhythmia, as well.
The stature and ponderal growth of affected children are normal. In cases with other heart malformations, like a ventricular septal defect, patent ductus arteriosus, pulmonic stenosis or aortic coarctation , the physical evaluation may fail to raise subvalvular aortic stenosis suspicion. Jugular inspection reveals a prominent "a" wave, caused by decreased compliance of the right ventricle. Arterial pulses are symmetrical and seldom decreased. Carotid palpation may prove the presence of an arterial thrill, while a precordial thrill may be felt upon palpation of this area. The apical impulse is strong. Auscultation highlights the existence of a narrow or paradoxical split second heart sound, associated with an ejection murmur, best heard in the middle left sternal border, radiating to the upper left border of the sternum, with a longer duration if the obstruction is more severe. The physician can differentiate this murmur from that of valvular aortic stenosis based on the absence of clicks. Other murmurs, like that of aortic or mitral regurgitations, sometimes coexist.
Jaw & Teeth
- Heart Disease
[…] of Adults With Congenital Heart Disease). [wikidoc.org]
The COACH program focuses on: Adults with congenital heart disease Pulmonary hypertension Cardiovascular connective tissue disorders Pregnancy in women with heart disease Transition of adolescents with congenital heart disease into adult congenital heart [wexnermedical.osu.edu]
Subvalvular aortic stenosis (SAS) is one of the common adult congenital heart diseases, with a prevalence of 6.5%. It is usually diagnosed in the first decade of life. Echocardiography is the test of choice to diagnose SAS. [ncbi.nlm.nih.gov]
Task Force 1: congenital heart disease. J Am Coll Cardiol 1994, 24 :867–873. [link.springer.com]
- Heart Murmur
In this case, it is incidentally discovered during a heart murmur evaluation. Symptoms tend to occur as the patient grows older and the lesion becomes more severe. [symptoma.com]
[…] if there is a history of a heart murmur in other close family members. [chop.edu]
A doctor hears this as a heart murmur. The subaortic membrane is twice as common in males. It has been reported in family clusters. It is more severe when diagnosed in children, rather than in adults. [achaheart.org]
On physical exam he was noted to have a systolic heart murmur. Echocardiogram showed severe left ventricular outflow tract obstruction. [cardiacmri.com]
Doctors sometimes hear a heart murmur (an odd, whooshing sound heard via stethoscope) due to the turbulence of blood flow through the narrowed area, after which, further tests might reveal subaortic stenosis. [childrens.memorialhermann.org]
- Precordial Thrill
Carotid palpation may prove the presence of an arterial thrill, while a precordial thrill may be felt upon palpation of this area. The apical impulse is strong. [symptoma.com]
Given that pure subvalvular aortic stenosis is a non-cyanotic congenital heart malformation, blood workup is usually noncontributory. The electrocardiogram depicts the degree of underlying left ventricular hypertrophy in most patients. The strain pattern, as well precordial deep Q waves are rarely seen.
Echocardiography is the diagnostic method of choice. This imaging is able to describe the shape of the left ventricular outflow tract, the degree of obstruction, the existence of associated congenital abnormalities, like aortic coarctation or patent ductus arteriosus  and disease consequences . The color doppler probe placed in the left ventricular outflow tract reveals a turbulent flow , the first obstruction indicator. The M-mode cursor put in the same area demonstrates the presence of early closure and flutter of the aortic valve leaflets. It is important to characterize the length and position of the lesions and their relationship with the mitral and aortic valves and this is done using parasternal, apical and subcostal views. The gravity of the disease is assessed by continuous doppler wave interrogation, based on mean pressure gradient across the left ventricle outflow tract. However, this is not a reliable method in tunnel-like or multiple lesions. In these cases, a cardiac catheterization with pullback pressure measurement is needed.
The echocardiography should be performed several times in order to observe disease progression, to characterize left and right ventricular filling and function and the impact of the condition on the aortic valve in terms of regurgitation  . In cases where the acoustic window is poor, diagnosis is aided by transesophageal echocardiography. This is most useful in severe, symptomatic patients that are going to be referred for surgery . Supplementary information, like the severity of mitral regurgitation, the existence of ventricular septal defects or the exact anatomy of the left ventricle is offered by a left ventriculogram.
Jugular Venous Pressure
- Left Ventricular Hypertrophy
Most (78%) were symptomatic, 79% had left ventricular hypertrophy (LVH) by electrocardiogram, and 92% had roentgenographic evidence of cardiomegaly preoperatively. [ncbi.nlm.nih.gov]
The electrocardiogram depicts the degree of underlying left ventricular hypertrophy in most patients. The strain pattern, as well precordial deep Q waves are rarely seen. Echocardiography is the diagnostic method of choice. [symptoma.com]
There is mild concentric left ventricular hypertrophy (LVH) due to increased left ventricular systolic pressure. [cardiacmri.com]
To our knowledge, this case report is the first to describe how this new drug combination therapy is an effective treatment of GB from angiodysplasias and can be used to bridge to surgical or endovascular treatment. [pure.au.dk]
Surgical correction is the best treatment modality, and the prognosis is usually excellent. [ncbi.nlm.nih.gov]
Surgical correction is the best treatment modality, and the prognosis is usually excellent. [ncbi.nlm.nih.gov]
Prognosis Although natural history studies have not delineated the annual mortality rate, 2-10% of sudden deaths are reported in untreated individuals with severe left ventricular outflow tract (LVOT) obstruction, including subvalvar aortic stenosis [emedicine.medscape.com]
Etiology The etiology of subvalvar aortic stenosis (SAS) still is not fully understood. [emedicine.medscape.com]
It can be classified as fixed or dynamic type depending on the dynamics of the obstruction.  Epidemiology and Demographics Aortic subvalvular stenosis is the second most common form of congenital left ventricular outflow tract obstruction and occurs [wikidoc.org]
However, the Newfoundland dog has been shown to experience an increased incidence of subaortic membranes, which may in part be secondary to inbreeding and is consistent with an autosomal inheritance.  Epidemiology The approximate incidence of congenital [emedicine.medscape.com]
In this review, we describe the pathophysiology, diagnosis, prognosis, and management of SAS with a focus on different pathophysiologic mechanisms, diagnostic approach, and prognosis of the disease by reviewing the current literature. © 2018 Wiley Periodicals [ncbi.nlm.nih.gov]
HOCM (a.k.a. idiopathic hypertrophic subaortic stenosis or IHSS ) is not present at birth and is not considered a congenital lesion.  Pathophysiology There are several varieties of congenital aortic subvalvular stenosis (or subaortic stenosis):  [wikidoc.org]
(See Pathophysiology and Treatment and Management.) Go to Aortic Stenosis for more complete information on this topic. [emedicine.medscape.com]
Consequently, it is reasonable to consider the role of alternative therapies which may help prevent recurrence in selected cases. [ncbi.nlm.nih.gov]
: Prevention of bacterial endocarditis: recommendations by American Heart Association. JAMA 1997, 77 :1794–1801. The most updated American Heart Association guidelines for bacterial endocarditis prophylaxis. CrossRef Google Scholar 17. Elkins RC. [link.springer.com]
One study demonstrated that early intervention before the development of a significant gradient (>40 mm Hg) may prevent recurrence. 4 The authors from the same study also suggested that a postoperative gradient of >10 mm Hg was associated with an increased [journals.lww.com]
Repair for discrete membranous stenosis is done to prevent damage to the aortic valve and to preserve left ventricular function. [mottchildren.org]
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- Barkhordarian R, Uemura H, Rigby ML, et al. A retrospective review in 50 patients with subaortic stenosis and intact ventricular septum: 5-year surgical experience. Interact Cardiovasc Thorac Surg. 2007;6:35–8.