Ch 11: Myocarditis, Cardiomyopathy, Tumors, Pericardium

Question 1

You take an echo of a patient recovering from a cold and see biventricular dilation of the heart with generalized myocardial hypokinesis. The patient recovers, but functional impairments of the heart persist and the patient eventually develops overt cardiomyopathy. What did they have?

Answer 1

• myocarditis
• most common in children aged 1-10
• most commonly viral (coxsackie and adenovirus)
• can also be bacterial (diptheria), rickettsial, fungal, autoimmune, or a hypersensitivity reaction

Question 2

Name two metabolic causes of high output heart failure

Answer 2

hyperthyroidism and thiamine deficiency (Beriberi)

- result in decreased peripheral vascular resistance and increased cardiac output

Question 3

This cardiomyopathy is described as a very enlarged heart with hypertrophy of both ventricles. The myocardium is flabby and pale, and adherent mural thrombi are often present. Classified as a systolic dysfunction.

Answer 3

• dilated cardiomyopathy
• primary type associated with defects in the genes that regulate force transmission in cell
• secondary type associated with ethanol use, cocaine, catecholamines, cyclophosphamide, or pregnancy

Question 4

A young basketball player was in a playoff game filled with heart-stopping suspense when he suddenly developed dyspnea, chest pain, and died. On autopsy, his heart was large and microscopically showed myofiber disarray. What is the diagnosis, and what was the cause of death?

Answer 4

• diagnosis: hypertrophic cardiomyopathy
• enlarged septum can cause outflow obstruction and mitral regurgitation
• cause of death: arrhythmia
• classified as a diastolic dysfunction

Question 5

This cardiomyopathy is marked by limited diastolic filling with normal contractile function. What is the disease and what are some causes?

Answer 5

• restrictive cardiomyopathy

- caused by: interstitial infiltrate (amyloid, sarcoid), endomyocardial disease, storage diseases

Question 6

What arrhythmias are the most common cause of sudden cardiac death?

Answer 6

ventricular tachycardia and ventricular fibrillation

• if under 35, usually due to hypertropic cardiomyopathy or congenital abnormalities
• if older, usually due to coronary artery disease

Question 7

Patient dies of embolic stroke. On autopsy, there is a gelatinous polypoid mass in the heart. What is the diagnosis and where was the tumor?

Answer 7

• myxoma
• many occur in left atrium, leading to mitral valve dysfunction and embolization
• microscopically, show loose stroma with abundant proteoglycans

Question 8

Doing a work up on a child, you find out they have a cardiac tumor. Assuming this is a primary heart tumor, what is the diagnosis and what underlying condition can this be associated with?

Answer 8

• rhabodomyoma
• involves both ventricles and sometimes atria (may obstruct valves)
• microscopically, cells with small central nuclei and glycogen rich cytoplasm with fibrillar processes –> SPIDER CELLS
• associated with tuberous sclerosis (mutations in TSC 1/hamartin and TSC 2/tuberin) in 1/3 of cases

Question 9

What type of cancer is most likely to metastasize to the heart?

Answer 9

malignant melanoma

Question 10

Your patient had a myocardial infarction 5 days ago. They suddenly experience dyspnea and chest pain. You observe markedly decreased BP and pulsus paradoxus, with a small amplitude and shifting axis on EKG. What happened?

Answer 10

• rupture of ventricle, causing a cardiac tamponade

- restricts filling of heart and decreases cardiac output

Question 11

Patient presents with sudden and severe substernal chest pain. On exam, you notice a friction rub. What do you suspect and what is a common cause of this condition?

Answer 11

• acute pericarditis (can be fibrinous, purulent, or hemorrhagic)
• follows viral infection or MI
• fibrinous effusion fluid is rich in protein and inflammatory cells

Question 12

Patient with a history of breast cancer presents with chest pain and dyspnea. On exam, the heart sounds are reduced, BP is elevated, and pulse pressure is narrowed. You notice peripheral edema. What do you suspect and what is the pathogenesis?

Answer 12

• constrictive pericarditis (be careful, this mimics right heart failure!)
• fibrosing disease with calcium deposits in the pericardium following acute pericardial injury (in this case, mediastinal radiation)
• heart has a hard time filling