Path II Flashcards
What are the two types of Valvular Heart disease (VHD)
- STENOSIS = failure of valve to open competely
–> leads to PRESSURE OVERLOAD of the heart
- INSUFFICIENCY = failure of the valve to close completely, thereby allowing reversed flow
–> leads to VOLUME OVERLOAD
**EITHER WAY THE HEART HAS TO DO MORE WORK**
define aortic stenosis
- Aortic stenosis = calcification of anatomically normal and congenitally bicuspid aortic valve
define aortic insufficiency
- Dialtion of the ascending aorta, usually related to hypertension and aging
define mitral stenosis
- often caused by rheumatic heart disease
- mitral ring calcification
define mitral insufficiency
- caused by myxomatous degeneration (mitral valve prolapse)
Describe aortic stenosis
- usually a cosnequence of ageing of anatomically normal or congenitally bicuspid balbes
- senile cacific aortic stenosis occurs in the seventh to ninth decade, whereas stenotic bicuspid tend to present in patients 50-70 years of age
- causes LEFT VENTRICULAR (PRESSURE OVERLOAD) HYPERTROPHY
Aortic valve insufficiency (AI)
- leaking of the aortic valve of the ehart causes blood to flow in reverse direction during ventricular diastole, from the aorta into the left ventricle
–> results in aortic backflow and massive Left ventricle hypertrophy with DILATION and Left ventricle failure
- ETIOLOGY: rheumatic or aging (most common)
- AORTIC ROOT DILATION PULLS LEAFLETS APART causing insuffiencey
Rheumatic fever and rheumatic heart disease
- Multisystem inflammatory disease that occurs few weeks after an episode of GROUP A STREP. PHARYNGITIS
- antigenic mimicry causes immune system to target human tissue such as heart valves, myosin and tropomyosin
- CHARACTERIZED BY:
–> migratory polyarthritis of large joints
–> pancarditis
–> subcutaneous nodules
–> erythema marginatum of the skin
–> Sydenham chorea
What are the early lesions of RHD
- EARLY = VERRUCAE on leaflets of valves
- LATE
–> thickening of alve occurs
–> fusion of commisures
–> also can have calcification along with RHD leadign to sclerosis and stenosis
- TARGETS MITRAL > AORTIC > TRICUSPID > PULMONIC in order
MITRAL VALVE STENOSIS
- Left atrium has to pump hard so it becomes dilated and enlarged
- so it backs up into the pulmonary arteries and lungs leading to Right heart failrue eventually
Calcified Mitral annulus
- degenerative calcific deposits can develop in the annulus of the mitral valve
- LEADS TO:
–> regurgitation by interfereing with phsyiologic contraction of valve ring
–> stenosis by impairing opening of mitral leaflets
–> arrhythmias and occasionally sudden death by penetration of calcium deposits to a depth sufficient to impinge on atroventricular conductions ystem
–> site for thombi that can embolize
MITRAL VALVE PROLAPSE
- One or both mitral valve leaflets are FLOPPY and prolapse, or BALLOON BACK, into the left atrium during systole (PARACUITES)
–>KEY HISTOLOGICAL CHANGE = MYXOMATOUS DEGERNATION
–> Cuases a MID SYSTOLIC CLICK
- Associated with MARFANS syndrome
describe clinical findings of mitral valve prolapse
- Most patients are asymptomatic
- Midsystolic click: diagnosis can be confirmed by echocardiography
- MINORITY OF PATIENTS have chest pain mimicking angina, dyspnea and fatigue
- SMALL PERCENTAGE CAN DEVELOP
–> infective endocarditis
–> chordal rupture
–> thromboembolism
–> Arrhythmias
Define ACUTE INFECTIVE ENDOCARDITIS
- Organisms HIGH VIRULUENCE
- STAPH AUREUS
- produces necrotizing, ulcerative, destructive lesions of normal or deformed valves
- Difficult to cure with antibiotics
- HIGH MORALITY
DESCRIBE SUBACUTE INFECTIVE ENDOCARDITIS
- Organisms lower virulence (low virulence think viridands
- STREP. VIRIDANS
- insidious infectiosn of deformed valves that are less destructive
- may pursue a protracted course of weeks to months, and cures are often produced with antibiotics
describe the cardiomyopathy and how it relates to ejection fraction and mechanisms of heart failure
