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Aortic stenosis

Updated : May 16, 2024





Background

Aortic stenosis is characterized by the narrowing of the aortic valve in the heart. The aortic valve is one of the four valves in the heart. It regulates the flow of oxygen-rich blood from the left ventricle of the heart into the aorta, the main artery that carries blood to the rest of the body. Aortic stenosis can impede this flow, leading to various symptoms and complications.

Aortic stenosis is often caused by the gradual buildup of calcium deposits on the aortic valve leaflets. This buildup makes the valve stiff and less mobile, reducing its ability to open fully. It can also be caused by congenital abnormalities, such as a bicuspid aortic valve, which is a valve with only two leaflets instead of the usual three.

Aortic stenosis is a relatively common heart valve disorder, especially in older adults. Degenerative aortic stenosis is the most common type typically seen in individuals over 65. Congenital aortic stenosis is present from birth and is less common.

Epidemiology

Aortic stenosis is primarily a disease of the elderly. It becomes more common with advancing age. The prevalence of aortic stenosis increases with age, and it is more common in individuals over 65 years old. The risk of developing this condition rises significantly in the later decades of life. Age is a major risk factor for aortic stenosis. The degenerative form of aortic stenosis is most common in elderly individuals.

Aortic stenosis affects men and women fairly equally, although some studies have reported a slightly higher prevalence in men. Some studies suggest that certain populations may be more prevalent due to genetic factors or lifestyle. As life expectancy increases and the population ages, the prevalence of aortic stenosis is expected to rise, making it a significant public health concern in many countries.

Anatomy

Pathophysiology

Aortic stenosis is characterized by the narrowing of the aortic valve, which plays a crucial role in regulating blood flow from the left ventricle of the heart to the aorta, the main artery supplying blood to the body. The pathophysiology of aortic stenosis primarily involves the gradual accumulation of calcium deposits on the aortic valve leaflets, causing them to become stiff and less flexible.

This calcification process impedes the valve’s ability to fully open, leading to an obstruction in the flow of oxygen-rich blood from the heart to the rest of the body. As a result, the left ventricle must work harder to overcome this obstruction, leading to hypertrophy of the heart muscle, which initially serves as a compensatory mechanism to maintain cardiac output.

However, this increased workload can lead to heart muscle dysfunction, heart failure, and other related symptoms such as chest pain, shortness of breath, and dizziness over time. In severe cases, aortic stenosis can result in diminished cardiac output and a reduced ability of the heart to meet the body’s oxygen demands, ultimately posing severe risks to an individual’s health.

Etiology

Acquired

Rheumatic valve disease

Systemic lupus erythematosus

Alkaptonuria

Ochronosis

End-stage renal disease

Hypertrophic cardiomyopathy

Congenital

Bicuspid aortic valve

Subvalvular stenosis

Valvar atresia

Genetics

Prognostic Factors

Clinical History

Acquired aortic stenosis typically presents with symptoms such as exertional dyspnea, angina, syncope, and, eventually, heart failure. The onset of these symptoms typically occurs around 50 to 70 in individuals with a bicuspid aortic valve and at over 70 years of age in those with calcific stenosis of the tri-leaflet valve.

Patients experience a progressive decline in their ability to engage in physical activities, accompanied by increasing dyspnea during exertion and persistent fatigue. As the condition advances, episodes of paroxysmal nocturnal dyspnea, severe exertional dyspnea, pulmonary edema, and orthopnea become evident, reflecting varying degrees of pulmonary venous hypertension.

Angina, another common symptom, arises from a combination of increased oxygen demand due to hypertrophy of the heart muscle and reduced oxygen supply caused by the compression of coronary vessels by the stenotic valve. Syncope, or fainting, can be attributed to decreased cerebral perfusion during physical activity when arterial pressure drops due to systemic vasodilation and an inadequate addition in cardiac output linked to aortic stenosis.

In severe cases, it may result from the impaired functioning of the baroreceptor mechanism. In addition to cardiac symptoms, non-cardiac manifestations can occur. Gastrointestinal bleeding, for instance, is observed in individuals with severe aortic stenosis and is often related to conditions like angiodysplasia or other vascular malformations.

This bleeding can be attributed to shear stress-induced platelet aggregation and a decrease in von Willebrand factor. Furthermore, there is a risk of cerebral emboli in aortic stenosis patients, adding to the spectrum of clinical considerations associated with this condition.

Physical Examination

During a clinical examination, the carotid upstroke can be assessed through palpation. In cases of severe aortic stenosis, a distinctive pattern known as pulsus parvus et tardus can be observed, characterized by a late-peaking, slow-rising, and low-amplitude carotid impulse. This finding is specific to aortic stenosis. When examined, the second heart sound may lack its usual split and can be heard as a single sound during inspiration.

In certain situations, it can even become paradoxical, indicating a delay in the closure of the aortic valve compared to the pulmonic valve. A mid-systolic ejection murmur, typically best heard over the right second intercostal space, is another hallmark of aortic stenosis. This murmur often radiates into the right side of the neck.

However, in cases of calcified aortic valves, there may be high-frequency components that radiate to the apex of the heart, a phenomenon referred to as the “Gallavardin phenomenon.” It’s important to note that this murmur may become softer in conditions like left ventricular failure or when there is a decrease in stroke volume.

Age group

Associated comorbidity

Associated activity

Acuity of presentation

Differential Diagnoses

Coronary Artery Disease

Hypertrophic Cardiomyopathy

Cardiac Amyloidosis

Pulmonary Stenosis

Mitral Stenosis

Laboratory Studies

Imaging Studies

Procedures

Histologic Findings

Staging

Treatment Paradigm

The management of aortic stenosis encompasses several approaches tailored to the severity of the condition and the patient’s health status. Medical management, including symptom relief and risk factor control, is suitable for mild to moderate cases. For severe aortic stenosis, various interventions are available.

Surgical Aortic Valve Replacement (SAVR) is the standard approach, while Transcatheter Aortic Valve Replacement (TAVR) offers a less invasive alternative for high-risk patients. Balloon valvuloplasty is used as a temporary solution or bridge to definitive treatment.

Watchful waiting may be considered for patients who are not surgical candidates. Lifestyle modifications and cardiac rehabilitation are crucial. The choice of treatment depends on individual factors and requires ongoing monitoring to ensure optimal patient care.

by Stage

by Modality

Chemotherapy

Radiation Therapy

Surgical Interventions

Surgical Aortic Valve Replacement

Surgical aortic valve replacement is the gold standard treatment for severe aortic stenosis. During this open-heart surgery, the affected aortic valve is removed, and it is replaced with either a mechanical or bioprosthetic valve. Mechanical valves are durable but require lifelong anticoagulation therapy, while bioprosthetic valves do not require anticoagulation but have a limited lifespan. The choice of valve depends on the patient’s age and individual factors.

Balloon Valvuloplasty

Balloon valvuloplasty is a minimally invasive procedure that involves inflating a balloon in the narrowed aortic valve to improve its opening. It is often used as a temporary solution for patients who are not surgical candidates or as a bridge to a more definitive treatment.

Transcatheter Aortic Valve Replacement

Transcatheter aortic valve replacement is a less invasive alternative to SAVR, primarily used for patients at high or prohibitive surgical risk. In TAVR, a replacement valve is inserted through a catheter, often through the femoral artery, and guided to the site of the stenotic valve. This procedure is associated with shorter recovery times and fewer complications, making it a suitable option for elderly or high-risk patients.

Hormone Therapy

Immunotherapy

Hyperthermia

Photodynamic Therapy

Stem Cell Transplant

Targeted Therapy

Palliative Care

Lifestyle Modifications

Lifestyle changes, such as managing blood pressure, controlling cholesterol levels, and quitting smoking, are essential components of aortic stenosis management. These modifications can help slow the progression of the disease and reduce the risk of complications. Cardiac rehabilitation programs can be beneficial for patients recovering from valve replacement procedures. These programs focus on exercise, education, and psychosocial support to enhance the patient’s physical and emotional well-being. 

Medication

Media Gallary

References

Aortic stenosis

Updated : May 16, 2024




Aortic stenosis is characterized by the narrowing of the aortic valve in the heart. The aortic valve is one of the four valves in the heart. It regulates the flow of oxygen-rich blood from the left ventricle of the heart into the aorta, the main artery that carries blood to the rest of the body. Aortic stenosis can impede this flow, leading to various symptoms and complications.

Aortic stenosis is often caused by the gradual buildup of calcium deposits on the aortic valve leaflets. This buildup makes the valve stiff and less mobile, reducing its ability to open fully. It can also be caused by congenital abnormalities, such as a bicuspid aortic valve, which is a valve with only two leaflets instead of the usual three.

Aortic stenosis is a relatively common heart valve disorder, especially in older adults. Degenerative aortic stenosis is the most common type typically seen in individuals over 65. Congenital aortic stenosis is present from birth and is less common.

Aortic stenosis is primarily a disease of the elderly. It becomes more common with advancing age. The prevalence of aortic stenosis increases with age, and it is more common in individuals over 65 years old. The risk of developing this condition rises significantly in the later decades of life. Age is a major risk factor for aortic stenosis. The degenerative form of aortic stenosis is most common in elderly individuals.

Aortic stenosis affects men and women fairly equally, although some studies have reported a slightly higher prevalence in men. Some studies suggest that certain populations may be more prevalent due to genetic factors or lifestyle. As life expectancy increases and the population ages, the prevalence of aortic stenosis is expected to rise, making it a significant public health concern in many countries.

Aortic stenosis is characterized by the narrowing of the aortic valve, which plays a crucial role in regulating blood flow from the left ventricle of the heart to the aorta, the main artery supplying blood to the body. The pathophysiology of aortic stenosis primarily involves the gradual accumulation of calcium deposits on the aortic valve leaflets, causing them to become stiff and less flexible.

This calcification process impedes the valve’s ability to fully open, leading to an obstruction in the flow of oxygen-rich blood from the heart to the rest of the body. As a result, the left ventricle must work harder to overcome this obstruction, leading to hypertrophy of the heart muscle, which initially serves as a compensatory mechanism to maintain cardiac output.

However, this increased workload can lead to heart muscle dysfunction, heart failure, and other related symptoms such as chest pain, shortness of breath, and dizziness over time. In severe cases, aortic stenosis can result in diminished cardiac output and a reduced ability of the heart to meet the body’s oxygen demands, ultimately posing severe risks to an individual’s health.

Acquired

Rheumatic valve disease

Systemic lupus erythematosus

Alkaptonuria

Ochronosis

End-stage renal disease

Hypertrophic cardiomyopathy

Congenital

Bicuspid aortic valve

Subvalvular stenosis

Valvar atresia

Acquired aortic stenosis typically presents with symptoms such as exertional dyspnea, angina, syncope, and, eventually, heart failure. The onset of these symptoms typically occurs around 50 to 70 in individuals with a bicuspid aortic valve and at over 70 years of age in those with calcific stenosis of the tri-leaflet valve.

Patients experience a progressive decline in their ability to engage in physical activities, accompanied by increasing dyspnea during exertion and persistent fatigue. As the condition advances, episodes of paroxysmal nocturnal dyspnea, severe exertional dyspnea, pulmonary edema, and orthopnea become evident, reflecting varying degrees of pulmonary venous hypertension.

Angina, another common symptom, arises from a combination of increased oxygen demand due to hypertrophy of the heart muscle and reduced oxygen supply caused by the compression of coronary vessels by the stenotic valve. Syncope, or fainting, can be attributed to decreased cerebral perfusion during physical activity when arterial pressure drops due to systemic vasodilation and an inadequate addition in cardiac output linked to aortic stenosis.

In severe cases, it may result from the impaired functioning of the baroreceptor mechanism. In addition to cardiac symptoms, non-cardiac manifestations can occur. Gastrointestinal bleeding, for instance, is observed in individuals with severe aortic stenosis and is often related to conditions like angiodysplasia or other vascular malformations.

This bleeding can be attributed to shear stress-induced platelet aggregation and a decrease in von Willebrand factor. Furthermore, there is a risk of cerebral emboli in aortic stenosis patients, adding to the spectrum of clinical considerations associated with this condition.

During a clinical examination, the carotid upstroke can be assessed through palpation. In cases of severe aortic stenosis, a distinctive pattern known as pulsus parvus et tardus can be observed, characterized by a late-peaking, slow-rising, and low-amplitude carotid impulse. This finding is specific to aortic stenosis. When examined, the second heart sound may lack its usual split and can be heard as a single sound during inspiration.

In certain situations, it can even become paradoxical, indicating a delay in the closure of the aortic valve compared to the pulmonic valve. A mid-systolic ejection murmur, typically best heard over the right second intercostal space, is another hallmark of aortic stenosis. This murmur often radiates into the right side of the neck.

However, in cases of calcified aortic valves, there may be high-frequency components that radiate to the apex of the heart, a phenomenon referred to as the “Gallavardin phenomenon.” It’s important to note that this murmur may become softer in conditions like left ventricular failure or when there is a decrease in stroke volume.

Coronary Artery Disease

Hypertrophic Cardiomyopathy

Cardiac Amyloidosis

Pulmonary Stenosis

Mitral Stenosis

The management of aortic stenosis encompasses several approaches tailored to the severity of the condition and the patient’s health status. Medical management, including symptom relief and risk factor control, is suitable for mild to moderate cases. For severe aortic stenosis, various interventions are available.

Surgical Aortic Valve Replacement (SAVR) is the standard approach, while Transcatheter Aortic Valve Replacement (TAVR) offers a less invasive alternative for high-risk patients. Balloon valvuloplasty is used as a temporary solution or bridge to definitive treatment.

Watchful waiting may be considered for patients who are not surgical candidates. Lifestyle modifications and cardiac rehabilitation are crucial. The choice of treatment depends on individual factors and requires ongoing monitoring to ensure optimal patient care.

Surgical Aortic Valve Replacement

Surgical aortic valve replacement is the gold standard treatment for severe aortic stenosis. During this open-heart surgery, the affected aortic valve is removed, and it is replaced with either a mechanical or bioprosthetic valve. Mechanical valves are durable but require lifelong anticoagulation therapy, while bioprosthetic valves do not require anticoagulation but have a limited lifespan. The choice of valve depends on the patient’s age and individual factors.

Balloon Valvuloplasty

Balloon valvuloplasty is a minimally invasive procedure that involves inflating a balloon in the narrowed aortic valve to improve its opening. It is often used as a temporary solution for patients who are not surgical candidates or as a bridge to a more definitive treatment.

Transcatheter Aortic Valve Replacement

Transcatheter aortic valve replacement is a less invasive alternative to SAVR, primarily used for patients at high or prohibitive surgical risk. In TAVR, a replacement valve is inserted through a catheter, often through the femoral artery, and guided to the site of the stenotic valve. This procedure is associated with shorter recovery times and fewer complications, making it a suitable option for elderly or high-risk patients.

Lifestyle changes, such as managing blood pressure, controlling cholesterol levels, and quitting smoking, are essential components of aortic stenosis management. These modifications can help slow the progression of the disease and reduce the risk of complications. Cardiac rehabilitation programs can be beneficial for patients recovering from valve replacement procedures. These programs focus on exercise, education, and psychosocial support to enhance the patient’s physical and emotional well-being.