Valve Disorders Flashcards
Heart Valves
- Tricuspid (3)
- Pulmonary (3)
- Mitral (2) [bicuspid]
- Aortic (3)
AV Valves
Tricuspid + Bicuspid (Mitral)
- Open during diastole to direct blood flow to ventricles
- Close during systole
Pulmonary + Aortic valves
- Open with systole directing blood flow from ventricles out of the heart
- Close during diastole
Valve abnormality causes
- Wear and Tear
- Calcification
- Pannus
- on leaflets of valves - Endocarditis
- infection of valves - Thrombus
Valve abnormalities (2 types)
Stenosis
- very tight/stiff and hard for the blood to get through
- ex) Aortic valve
Regurgitation
- Very loose and blood flows backward with increased pressures
- ex) Atria (mitral/bicuspid valve)
What happens to the heart muscle when it has to pump against a STENOTIC valve?
Cannot close or open as FULLY
Heart muscle develops HYPERTROPHY (increases in size)
Aortic Stenosis Triad (SAD)
**Not everyone has symptoms
SAD
- (Syncope) Lightheadedness
- (Angina) Chest pain
- (Dyspnea) Short of breath
These symptoms often occur with EXERTION
Mitral Regurgitation: symptoms
Fatigue
-not enough blood
Shortness of breath
-pulmonary symptoms
Usually need surgey
Infective Endocarditis (IE)
Vegetations on the valves can become septic emboli
- can be seen on ECHO
- depending on which valve it can land in lungs or periphery
Infective Endocarditis (IE): risk factors
- Prosthetic Valve
- Pacemaker-associated
- IVDA
- Streptococcus viridians
- Staphylococcus aureus
- Staphylococcus epidermidis
In drug users, vegetations are most often seen on which valve?
Tricuspid
Symptoms of Infective Endocarditis (IE)
Fever Chills Anorexia Weight loss Myalgias: pain in muscles Arthralgias: joint pain Heart murmur
Signs of ischemia or infarction of the extremities, spleen, kidney, bowel, or brain may be the initial clinical manifestation
Septic emboli of brain
Septic emboli can lodge in a cerebral artery or arteriole and cause an ISCHEMIC STROKE. Neurological symptoms from embolic stroke occur in up to 40% of patients with IE. Patients may also present with meningitis, seizures, encephalopathy, or abscesses of the brain
IE patient Labs
Will have + blood cultures
-long term antibiotic treatment
What are septic emboli in IE?
Microorganisms travel into the heart, adhere to damaged endothelial tissue, and attract WBCs and platelets, which release cytokines and coagulation factors
Stimulation of the coagulation cascade results in fibrin deposition and eventually, development of a vegetation
Vegetations are most commonly found on valve leaflets, fragments of vegetations can EMBOLIZE into circulation
Carried by the bloodstream, these fragments, called SEPTIC EMBOLI, can initiate infection or ischemia in remote tissues.
Manifestations of IE
Often caused by septic emboli: Mitral Valve to systemic circulation:
- Petechiae
- Splinter hemorrhages: linear streaks in the nailbeds
- Janeway lesions: erythematous, nontender lesions on the palms and soles
- Osler’s nodes: subcutaneous nodules in the pulp of the fingertips
- Roth spots: oval retinal hemorrhages with pale centers
IE in IV Drug Users
In IV drug users the veins are the portal of entry and Staphylococcus aureus, the flora of the SKIN, most commonly causes bacteremia
S. aureus travels from the peripheral vein into the INFERIOR VENA CAVA and into the RIGHT side of the heart
The TRICUSPID VALVE is most often affected in IV drug users
Septic emboli can enter the PULMONARY ARTERY (Lungs)
The Duke Criteria of IE
Infective endocarditis requires:
- 2 major criteria are met
- 1 major + 3 minor criteria
- 5 minor criteria
IE Antibiotic therapy
Blood culture results identify organism and best antibiotic therapy
Prolonged therapy (4-6 weeks) -could be 8-10 weeks
Lengthy hospital stay!
