(MHD) Cardiomyopathies Flashcards
(32 cards)
Define a cardiomyopathy
It is a primary abnormality of the myocardium. This means that cardiac dysfunction is not attributable to pressure or volume overload.
What are the (3) general categories of cardimyopathy?
- Dilated
- Hypertrophic
- Restrictive
How common is dilated cardiomyopathy?
The most common type of cardiomyopathy
What kind of dysfunction is dilated cardiomyopathy? What are its causes? (5)
It is a contractile (systolic) dysfunction.
It has genetic causes (vary)
and Non-genetic causes:
- Myocarditis
- Peri partum (in association with pregnancy)
- Toxicity (alcohol)
- Idiopathic (which are actually most likely genetic)
What is the clinical manifestation of dilated cardiomyopathy? (3)
Progressive systolic CHF, arrhytmias and potential thrombi w/ embolic complications.
General treatment for dilated cardimyopathy
Medications or heart transplant (last resort)
Hypertrophic cardiomyopathy is also known as … (2)
Idiopathic hypertrophic subaortic stenosis and hypertrophic obstructive cardiomyopathy
Describe the changes to the heart associated with hypertrophic cardiomyopathy
- Septum is more enlarged then the otherfree wall, forming Banana shaped LV cavity.
- There is abnormal diastolic filling
- There can be left ventricular outflow obstruction
- There can be endocarditis as a result of the wall rubing the valve during systole.
- Myofibral dissarray
What is the pathogenesis for hypertrophic cardiomyopathy? How much of it is caused by genetics?
Mutations in genes that encode proteins of the sarcomeres, leading to hypercontractility and associated hypertrophicity.
100% genetic
What is the #1 cause of sudden death for young athletes?
Hypertrophic Cardiomyopathy
Treatment of hypertrophic cardiomyopathy (2)
- Medical therapy enhancing ventricular relaxation
- Surgical excision of some of the muscle
Describe restrictive cardiomyopathy
Decrease in ventricular compliance, which leads to impeded left ventricular filling during diastole. The cavity is a normal size.
How is systolic functin effected during restrictive cardiopathy?
Its function is preserved.
What are (2) major things which can cause restrictive cardiomyopathy?
- Radiation fibrosis
- Amyloidosis
Describe amyloidosis
Misfolded proteins deposit and accumulate in the heart (and other tissues), causing tissue damage. Can lead to restrictive cardiomyopathy
What are the key common features of ALL amyloid deposits, regardess of the proteins causing them? (what is their structure? describe their staining.)
- B-pleated sheet configuration
- Stain salmon pink with congo red staining and appear “apple-green” under polarized light.
What is the most common cause of myocarditis? How does it work?
Viruses (particularly enteroviruses)
Bacteria, parasites and other noninfectious methods can also cause it.
Infection causes lymphocytes to infiltrate and injury/ destroy the myocytes.
What are the noninfectious causes of Myocarditis? (3)
- Immune-mediated (hypersensitivty rxns and rheumatic fever)
- Giant cell myocarditis
- Sarcoidosis
Describe the clinical manifestations of myocarditis
They are a spectrum.
Can range from asymptomatic to CHF or sudden cardiac death
What is a pericardial effusion? How is it treated?
When there is too much fluid in the pericardial sac due to blood, pus, serous, etc.
Must put a catheter to drain the fluid if there is too much
Less than _______mL of slowly accumulating fluid may not be clinically signficant as far as pericardial effusions are concerned
500mL
(acute accumulation on the other hand would be an issue, even less than 500mL)
What is the issue with rapidly filling or large pleural effusions? What can it lead to?
They can compress the heart to the point that it can’t function properly and can ultimately lead to cardiac tamponade.
What is pericarditis?
Inflammation of the pericardium, secondary to cardiac, thoracic or systemic process.
Describe fibrinous pericarditis. (how does the pericardium look? What can you hear?)
FIbers deposit on the pericardium causing a shaggy appearance. You can often hear pericardial friction rubbing as the heart beats.
