467
edits
Valvular Heart Disease: Difference between revisions
Jump to navigation
Jump to search
no edit summary
No edit summary |
No edit summary |
||
| Line 60: | Line 60: | ||
The first detectable macroscopic modifications of the calcification process is named aortic valve sclerosis. <cite>Rajamannan</cite> Aortic sclerosis, seen as calcification or focal leaflet thickening with normal valve function, was detected in 25% of people at 65 years of age, this increases to 48% in people aged >75% in a population-based echocardiographic study.<cite>Otto</cite> <cite>Otto2</cite> | The first detectable macroscopic modifications of the calcification process is named aortic valve sclerosis. <cite>Rajamannan</cite> Aortic sclerosis, seen as calcification or focal leaflet thickening with normal valve function, was detected in 25% of people at 65 years of age, this increases to 48% in people aged >75% in a population-based echocardiographic study.<cite>Otto</cite> <cite>Otto2</cite> | ||
The prevalence of calcified aortic stenosis is estimated at 2 % of people 65 years of age, increasing to 3-9% after the age of 80 years.<cite>Nkomo</cite><cite> | The prevalence of calcified aortic stenosis is estimated at 2 % of people 65 years of age, increasing to 3-9% after the age of 80 years.<cite>Nkomo</cite><cite>Otto2</cite> | ||
Calcified degenerative aortic valve stenosis was previously considered to be the result of a passive degenerative process due to longterm mechanical stress in combination with calcium accumulation. Recently this concept is revised. Calcified degenerative aortic stenosis is considered an active pathobiological process, including proliferative and inflammatory changes, lipid accumulation, renin-angiotensin system activation, valular interstitial cell transformation, ultimately resulting in calcification of the aortic valve.<cite>RajamannanGershBonow</cite><cite>Rajamannan2</cite> <cite>OBrien</cite> <cite>Mohler</cite> Risk factors for development of calcific aortic stenosis are similar to those for vascular atherosclerosis such as diabetes, hypertension, and cholesterol levels.<cite>Stewart</cite> <cite>Stritzke</cite> Progressive calcification leads to immobilization of the cusps causing stenosis. | Calcified degenerative aortic valve stenosis was previously considered to be the result of a passive degenerative process due to longterm mechanical stress in combination with calcium accumulation. Recently this concept is revised. Calcified degenerative aortic stenosis is considered an active pathobiological process, including proliferative and inflammatory changes, lipid accumulation, renin-angiotensin system activation, valular interstitial cell transformation, ultimately resulting in calcification of the aortic valve.<cite>RajamannanGershBonow</cite><cite>Rajamannan2</cite> <cite>OBrien</cite> <cite>Mohler</cite> Risk factors for development of calcific aortic stenosis are similar to those for vascular atherosclerosis such as diabetes, hypertension, and cholesterol levels.<cite>Stewart</cite> <cite>Stritzke</cite> Progressive calcification leads to immobilization of the cusps causing stenosis. | ||
| Line 96: | Line 96: | ||
Symptoms of degenerative aortic stenosis manifest with progression of the disease. The first symptoms usually commence in the seventh or eight decade. Symptoms are typically noted on exertion. Dyspnoea on exertion is the most common encountered first symptom. Other symptoms are angina, precipitated by exertion and relieved by rest, syncope and heart failure. The findings on physical examination vary with the severity of the disease. On auscultation, a systolic ejection crescendo-decrescendo murmur, radiating to the neck is audible, often accompanied by a thrill. An elevated left ventricular pressure in patients with aortic stenosis, in conjunction with mitral annulus calcifications predisposes to rupture of mitral chordae tendineae, which may produce a regurgitant systolic murmur.<cite>Brener</cite> <cite>Mihaljevic</cite> | Symptoms of degenerative aortic stenosis manifest with progression of the disease. The first symptoms usually commence in the seventh or eight decade. Symptoms are typically noted on exertion. Dyspnoea on exertion is the most common encountered first symptom. Other symptoms are angina, precipitated by exertion and relieved by rest, syncope and heart failure. The findings on physical examination vary with the severity of the disease. On auscultation, a systolic ejection crescendo-decrescendo murmur, radiating to the neck is audible, often accompanied by a thrill. An elevated left ventricular pressure in patients with aortic stenosis, in conjunction with mitral annulus calcifications predisposes to rupture of mitral chordae tendineae, which may produce a regurgitant systolic murmur.<cite>Brener</cite> <cite>Mihaljevic</cite> | ||
The first heart sound is usually normal or soft in patients with aortic stenosis. The second heart sound may be delayed due to prolongation of systolic ejection time. The S<sub>2</sub> also may be single because of superimposed aortic and pulmonic valve components, or the aortic valve component is absent or soft because the aortic valve is too calcified and has become immobile. If the aortic component is audible, this may give rise to a paradoxical splitting of S<sub>2</sub>. A pronounced atrial contraction can give rise to a palpable and audible | The first heart sound is usually normal or soft in patients with aortic stenosis. The second heart sound may be delayed due to prolongation of systolic ejection time. The S<sub>2</sub> also may be single because of superimposed aortic and pulmonic valve components, or the aortic valve component is absent or soft because the aortic valve is too calcified and has become immobile. If the aortic component is audible, this may give rise to a paradoxical splitting of S<sub>2</sub>. A pronounced atrial contraction can give rise to a palpable and audible S4. | ||
When stroke volume and systolic pulse pressures fall in severe aortic stenosis, a pulsus parvus (small pulse) may be present. A wide pulse pressure is also characteristic of aortic stenosis. A pulsus parvus et tardus (the arterial pulse is slow to increase and has a reduced peak) can be appreciated by palpating the carotid pulse of patients with severe aortic stenosis. The stenotic valve decreases the amplitude and delays the timing of the carotid upstroke. Rigidity of the vasculature may hamper this sign in the elderly. | When stroke volume and systolic pulse pressures fall in severe aortic stenosis, a pulsus parvus (small pulse) may be present. A wide pulse pressure is also characteristic of aortic stenosis. A pulsus parvus et tardus (the arterial pulse is slow to increase and has a reduced peak) can be appreciated by palpating the carotid pulse of patients with severe aortic stenosis. The stenotic valve decreases the amplitude and delays the timing of the carotid upstroke. Rigidity of the vasculature may hamper this sign in the elderly. | ||