SM 146 Myocardial Pathology Flashcards
What parasite cause myocarditis in immunocompromised patients?
Toxoplasmosis
What are the subtypes of Restrictive Cardiomyopathy?
Myocardial and Endomyocardial
What does acute pericarditis result in?
Depends on the underlying cause, but can result in constrictive heart failure due to impairment of diastolic filling
Which cardiomyopathy is a “final common pathway”?
Dilated cardiomyopathy, with causes stemming from excess alcohol, viral illness, pregnancy, and heredity
What are causes of acute pericarditis?
Viral infection, immune diseases, acute MI (Dressler’s syndrome)
Drugs/immune related
Physical agents
Granulomatous
What is the end result of myocarditis?
Congestive heart failure, and occasionally cardiac death
What are cardiomyopathies?
A heterogenous group of diseases with intrinsic myocardial dysfunction as their common feature, may be primary or secondary
What is the most common tumor in the heart?
Primary heart tumors are rare, but the most common is Cardiac Myxoma, involving the LA or Mitral Valve
How does RCM present?
Right sided heart failure and secondary to systemic disease
What parasite can cause myocarditis?
T. cruzi, via Chagas disease, which dilates the heart
What causes Myocardial Restrictive Cardiomyopathy?
Infiltrative processes and generalized illness
What are the 3 types of primary cardiomyopathies?
Dilated, Hypertrophic, and Restrictive
How are the atria and ventricles separated?
Dense fibrous tissue insulates both compartments and forms separate electrically linked syncytia
How does HOCM present?
Dyspnea, angina, cardiomegaly, and a crescendo decrescendo systolic murmur
Why is hypertrophy of cardiomyocytes potentially bad?
Although it initially increases function, eventually it leads to failure
What can cause an immune-related myocarditis?
Cardiac transplantation
How does dilated cardiomyopathy present?
Congestive heart failure, fatigue, and embolitic events
How do the parietal pericardium and visceral pericardium differ?
Parietal pericardium is an outer fibrous sac made of collagen, and cannot stretch
Visceral pericardium aka epicardium is a serous sac that adheres to the surface of the heart, and contains the arteries, nerves and lymphatics that supply the heart
Cardiac tamponade will rapidly result in the heart being unable to fill since the parietal pericardium does not stretch
What can cause myocarditis?
Any microorganism, commonly viral, but also bacterial, fungal, and parasitic
What are infiltrative processes?
Amyloidosis, sarcoidosis, hemochromatosis
What can an autopsy of dilated cardiomyopathy show?
4 chamber dilation, especially of the ventricles
What is a secondary cardiomyopathy?
A cardiomyopathy extrinsic to the myocardium (drug toxicity) or part of a systemic process (amyloidosis)
How does Myxoma effect the heart?
Myxomas impair ventricular filling, and cause a diastolic murmur that varies with the patient’s position
What causes hypertrophic cardiomyopathy?
Hypertrophy of the ventricular muscle in the absence of hemodynamic load
What causes Endomyocardial Restrictive Cardiomyopathy?
Diseases that are limited to the subendocardial myocardium, such as Lofflers eosinophilic endocarditis
Mutations in which proteins lead to HOCM?
Mutations in contractile proteins lead to HOCM
Which side of the heart does Restrictive Cardiomyopathy effect and why?
Restrictive cardiomyopathy prevents diastolic filling and effects the right side of the heart, leading to right sided heart failure
What are the types of secondary cardiomyopathies?
Toxic, metabolic, storage, infiltrative, and neuromuscular
Which portion of the heart is most enlarged in HOCM?
The IV Septum, which obstructs left ventricular outflow
What is a primary cardiomyopathy?
A cardiomyopathy that is intrinsic to the myocardium and may be of unknown cause
