Diseases of the Heart Muscle and Pericardium Flashcards
Most common type of cardiomyopathy
Dilated Cardiomyopathy
Dilated Cardiomyopathy pathogenesis
An insult (ischemia, infection, alcohol, etc) —>dysfunction of LV contractility –>Dilated LV
*50% of cases are idiopathic
Treatment of dilated cardiomyopathy
Similar to treatment of CHF because signs and symptoms of both R and L sided failure are likely present
Digoxin
Diuretics
Vasodilators
Heart Transplant
What sort of prophylaxis should be considered in patients with dilated cardiomyopathy?
Anticoagulation because these patients are at increased risk of embolization
most cases of hypertrophic cardiomyopathy are due to….
Inheritance of an autosomal dominant trait
What kind of cardiac dysfunction will hypertrophic cardiomyopathy cause?
Diastolic dysfunction due to a stiff, hypertrophied ventricle with increased diastolic filling pressures that increase further with elevated heart rate and contractility (as with exercise)
Patients with hypertrophic cardiomyopathy may have this obstruction:
dynamic outflow obstruction due to assymmetric hypertrophy of the interventricular septum
young athlete experiences sudden death: may be the first manifestation of….
hypertrophic cardiomyopathy
Clinical signs of HCM
sustained PMI
Loud s4
systolic ejection murmur
rapidly increased carotid pulse with 2 upstrokes (bisferious pulse)
Systolic Ejection murmur in HCM is best heard at….
the lower left sternal border
standing, the valsalva maneuver, and leg raises diminish the intensity of which murmurs?
Diminish intensity of all murmurs except in Mitral Valve Prolapse and HCM
*These maneuvers decrease LV volume, thus make these two murmurs worse
Squatting increases the intensity of all murmurs except….
Mitral valve prolapse murmur and HCM murmur
Sustained hand grip decreases intensity of this murmur
HCM murmur
Sustained hand grip increases systemic resistance
All HCM patients should avoid…..
strenuous exercise including competitive sports
What is the initial drug used in symptomatic HCM patients? What is an alternative drug choice?
Beta blockers: decrease symptoms by improving diastolic filling via decreased HR and increasing diastole duration and decreasing contractility (and thus O2 consumption)
Calcium Channel Blockers (Verapamil) are alternatives if patient is not responding to the Beta Blockers (via similar mechanism)
This procedure is reserved for HCM patients with severe disease
Myomectomy: excision of part of the myocardial septum (Has high success rate for relieving symptoms)
Pathogenesis of Restrictive Cardiomyopathy
Infiltration of myocardium —> impaired diastolic ventricular filling due to decreased ventricular compliance
Causes of RCM
Amyloidosis Sarcoidosis Scleroderma Carcinoid Syndrome Chemo/Radiation therapy Hemochromatosis Idiopathic
RCM on echocardiogram will show:
Thickened myocardium
Increased RA and LA size with normal LV and RV size
*Possible systolic ventricular dysfunction
Signs and Symptoms of RCM
Dyspnea
Exercise intolerance
R-sided HF signs and symptoms (due to increased filling pressures)
Echo findings show myocardium appearing righter than normal with a possibly speckled appearance; you should suspect….
RCM caused by amyloidosis
In the treatment of RCM, you must treat the underlying disorder. You can give digoxin if systolic dysfunction is present, except when….
Patient has cardiac amyloidosis because these patients have increased incidence of digoxin toxicity
Myocarditis Causes
Inflammation of the myocardium caused by: virus bacteria SLE medications idopathic
“Classic Case” for myocarditis
Patient that is a young male
may present with fever, fatigue, chest pain, pericarditis, CHF, arrhythmia
Should look for these labs in myocarditis
cardiac enzymes elevated
ESR elevated
Cardinal manifestations of acute pericarditis
Chest pain
Pericardial friction rub
ECG changes: diffuse ST elevation and PR depression
Pericardial effusion (with or without tamponade)
How can you differentiate the chest pain of pericarditis from that of an MI?
Chest pain in acute pericarditis is pleuritic (associated with breathing) this is not the case in MI
Chest pain in acute pericarditis is aggravated by….
lying supine
coughing
swallowing
deep inspiration
Chest pain in acute pericarditis is relieved by….
sitting up and leaning forward
A pericardial friction rub is heard best under these conditions:
Heard best during expiration with patient sitting up and stethoscope placed firmly against chest
In acute pericarditis, the ECG may show 4 changes in sequence:
- diffuse ST elevation and PR depression
- ST segment returns to normal around 1 week
- T wave inverts (does not occur in all patients)
- T wave returns to normal
Treatment of acute pericarditis
NSAIDs are the mainstay
Most cases are self limited and resolve in 2-6 weeks
Pathophysiology of constrictive pericarditis
Fibrous scarring of pericardium—> rigidity and thickening of the pericardium —>obliterates pericardial cavity—> diastolic dysfunction
Compare diastolic dysfunction of constrictive pericarditis to that of cardiac tamponade
Constrictive pericarditis: Early diastole has rapid filling, late diastole has halted filling
In cardiac tamponade, ventricular filling is impeded throughout diastole
Patients with constrictive pericarditis typically present in 1 of 2 ways:
- symptoms characteristic of overload: edema, ascites, pleural effusion
- symptoms related to decreased C.O.: dyspnea on exertion, fatigue, decreased exercise tolerance, cachexia
most prominent physical finding in restrictive pericarditis:
JVD (may have kussmaul sign) with prominent x and y descent waveforms
Kussmaul sign
JVD fails to decrease during inspiration
If a patient has clinical signs of cirrhosis and distended neck veins, you need to considers and rule this out:
restrictive pericarditis
how is the diagnosis of restrictive pericarditis made?
by finding thickened pericardium on echocardiogram or CT/MRI
Treatment of restrictive pericarditis
must treat underlying condition!!
Diuretics to relieve symptoms of overload
Surgical pericardiectomy (indicated in most cases)
often, restrictive pericarditis progresses to…..
worsening C.O. and hepatic and/or renal failure
pericardial effusion can occur in association with
ascites and pleural effusion in CHF, cirrhosis, and nephrotic syndrome
diagnosis of pericardial effusion made by….
echocardiogram findings (most sensitive and specific method)
CXR may show cardaic silhouette enlargement when >250mL of fluid present, without pulmonary vascular congestion
pericardial effusion is important clinically when it…
develops rapidly because it may lead to cardiac tamponade
when would pericardiocentesis be indicated?
when there is evidence of cardiac tamponade
what is the most important factor in fluid accumulation that leads to cardiac tamponade?
It is the RATE of fluid accumulation that is important, not the amount
When fluid accumulates slowly, the pericardium has opportunity to stretch and adapt to the increasing volume
In cardiac tamponade, how do the various pressures in and around the heart affect the C.O.?
Pressures in the RV, LV, RA, LA, pulmonary artery and pericardium equalize during diastole—>
Impaired diastolic ventricular filling—>
Decreased stroke volume—-> decreased C.O.
Causes of Cardiac tamponade
Penetrating trauma to thorax
Iatrogenic causes: central line placement, pacemaker insertion etc.
Pericarditis: idiopathic neoplastic, or uremic
Post MI with free wall rupture
What is the most common finding in cardiac tamponade?
increased jugular venous pressure
Venous waveforms: prominent x descent and absent y descent
Pulsus Paradoxus
exaggerated decrease in arterial pressure during inspiration (>10mmHg drop)
Decrease in amplitude of femoral or carotid pulse with inspiration and strong pulse with expiration
Seen in Cardiac Tamponade
What is the Beck Triad for Cardiac Tamponade
Hypotension
Muffled Heart Sounds
JVD
Diagnosis of cardiac tamponade made by….
echocardiogram (most sensitive and specific non-invasive test)
Electrical Alternans on ECG
Alternate beat variation in the direction of the ECG wave forms due to pendular swinging of the heart within the pericardial space causing a motion artifact
Treatment for hemodynamically stable non-hemorrhagic tamponade
Closely monitor with Echo and ECG
If there is known renal failure—> dialysis would be more appropriate than pericardiocentesis
Treatment of hemodynamically unstable non-hemorrhagic tamponade
Pericardiocentesis
Treatment of hemorrhagic cardiac tamponade secondary to trauma
Emergency surgery!!!
Pericardiocentesis is NOT a definitive treatment, though it may alleviate symptoms.
Surgery should NOT be delayed to perform pericardiocentesis.
