Cardiomyopathy Flashcards
1
Q
Disorder characterized by morphologically and functionally abnormal myocardium in the absence of any other disease that is sufficient, by itself, to cause the observed phenotype
A
Cardiomyopathy
2
Q
What does cardiomyopathy exclude?
A
Cardiac dysfunction caused by structural heart disease such as CAD, primary valve disease, HTN
3
Q
What are the traditional classifications of cardiomyopathy?
A
- Dilated cardiomyopathy
- Restrictive cardiomyopathy
- Hypertrophic cardiomyopathy
4
Q
What are the WHO/ISFC classifications of cardiomyopathy?
A
- Dilated, Hypertrophic, Restrictive
AND - Arrhythmogenic right ventricular cardiomyopathy/dysplasia
- Unclassified cardiomyopathies
5
Q
In addition to the traditional classification and WHO/ISFC classification, cardiomyopathy can be classified as what?
A
- Intrinsic vs extrinsic
- Primary vs secondary
- Ischemic vs nonischemic
6
Q
What are types of familial/genetic cardiomyopathy?
A
- Unidentified gene defect
- Disease sub-type
7
Q
What are types of non-familial/non-genetic cardiomyopathy?
A
- Idiopathic
- Disease sub-type
8
Q
What does cardiomyopathy predominantly involve?
A
- LV
- Dysfunction of systole, diastole, or both
9
Q
How can the presentation of cardiomyopathy range?
A
- Asymptomatic to decompensated CHF to cardiac arrest
10
Q
What are diagnostic modalities for cardiomyopathy?
A
- Echocardiography
- nuclear imaging
- coronary angiography w/ left ventriculography
- Cardiac MRI
Dysfunction can be transient or permanent
11
Q
What does systolic dysfunction cause?
A
- Decrease in myocardial contractility and reduction in LVEF
- Compensatory mechanisms of LV enlargement resulting in higher stroke volume
- Frank-Starling relationship (increased stretch= increased contractility
- Eventually will lead to HF
12
Q
What does diastolic dysfunction cause?
A
- Cardiac dysfunction d/t abnormal LV relaxation and filling, accompanied by elevated filling pressures
13
Q
What is the relationship between diastolic dysfunction and systolic dysfunction?
A
May occur with or without systolic dysfunction but always present if systolic dysfunction occurs
14
Q
What is one problem with diastolic dysfunction diagnosis?
A
More difficult to quantify on echo so often underestimated or missed
15
Q
What is myocarditis?
A
- Inflammatory, infiltrative process involving the myocardium caused by infectious and noninfectious conditions
- May be acute, subacute, or chronic
- Results in necrosis and/or degeneration of myocytes
16
Q
What can myocarditis lead to?
A
- Myocardial dysfunction
- Dilated cardiomyopathy
17
Q
What is the pathogenesis of myocarditis?
A
- Varies depending on underlying cause (often undetermined)
- 2 main mechanisms: host-mediated and autoimmune mediated
18
Q
What causes host-mediated myocarditis?
A
direct cytotoxic effect of the causative agent
19
Q
What causes autoimmune-mediated myocarditis?
A
secondary immune response
20
Q
What are the 2 main phases of myocardial damage in myocarditis?
A
- Acute phase and chronic phase
21
Q
What are characteristics of the acute phase of myocarditis?
A
- First 2 weeks
- Myocyte death is a direct result of the causative agent, leading to cell-mediated cell toxicity
22
Q
What are characteristics of the chronic phase of myocarditis?
A
- Post 2 weeks
- Result of inappropriate, overactive immune response
23
Q
What are 3 infectious causes of myocarditis to know?
A
- Adenovirus (COVID-19)
- Coxsackie B virus
- Cytomegalovirus
24
Q
What are 3 noninfectious causes of myocarditis to be aware of?
A
Cardiotoxins:
- Alcohol
- Anthracyclines
- Cocaine
25
Which group has a slightly higher mortality rate due to myocarditis?
Men
26
What is the epidemiology of myocarditis?
* Frequency poorly defined due to variability of clinical presentation
* MC in patients 20-50 y/o
27
What is the presentation of myocarditis?
* Days to few weeks after onset of acute febrile illness/respiratory infection
* No known underlying cardiac pathology***
* SOB, pleural/pericardial chest pain, +/- fever, chills
* Could present with HF
* Palpitations, syncope, or sudden death may occur due to arrhythmias
28
What are the classic symptoms of myocarditis?
* SOB, pleural/pericardial chest pain, +/- fever, chills
29
If a patient with myocarditis has HF, what presentation may be present?
Gradual or abrupt
* Decreased cardiac output
* shock
* Severely depressed LV systolic function
30
What will be present on physical exam of myocarditis?
Heart auscultation:
* Pericardial friction rub
* Tachycardia
* S3 or S4
* Murmur of mitral or tricuspid regurgitation if ventricular dilation is severe
Heart failure: Volume overload
31
What initial testing should be performed for myocarditis?
* EKG
* Cardiac biomarkers
* CXR
32
What will be findings of the EKG, cardiac biomarkers, and CXR in myocarditis?
* EKG: sinus tachycardia, dysrhythmias, ventricular ectopy (PVCs), ST-T changes
* Cardiac biomarkers: elevated troponin levels common (esp. in rapid onset myocarditis)
* CXR: typically nonspecific, but may see cardiomegaly, pulmonary edema, pleural effusion
33
What additional testing can be performed for myocarditis?
* Labs: CRP, ESR (elevated), CBC (eosinophilia), +/- rheumatologic workup, serum viral antibody titers, BNP (in setting of HF)
* Transthoracic echo
* Cardiac MRI
* Endomyocardial biopsy
34
Does a transthoracic echo need to be performed in myocarditis? Why or why not?
* Yes! It is critical
* Allows visualization of myocardium, assessment of ventricular function, helps to r/o other pathology
35
Why would a cardiac MRI be performed?
* Helps assess extent of inflammation, myocyte necrosis and scarring, ventricular size/shape changes, wall motion abnormalities, and pericardial effusion
* Can suggest myocarditis, but sensitivity and specificity are limited and time dependent
## Footnote
Cardiology will decide whether or not to perform cardiac MRI
36
37
What does concrete confirmation of myocarditis require?
Histological evidence
## Footnote
Most cases are presumed
38
When would endomyocardial biopsy be obtained?
If there is a high probability that results will change patient management
## Footnote
Not our call (cardiology) and has limited sensitivity and specificity
39
When is endomyocardial biopsy recommended by the AHA/ACC?
* Fulminant, unexplained HF (new onset <2 weeks w/hemodynamic compromise)
* Unexplained new onset HF 2 weeks-3 months w/dilated LV, new ventricular arrhythmia, Mobitz II 2nd degree AV block, 3rd degree block or failure to respond to usual care in 1-2 weeks
40
When is EMB suggested by AHA/ACC?
* HF >3 months with dilated LV, new ventricular arrhythmia, Mobitz II 2nd degree AV block, 3rd degree block or failure to respond to usual care in 1-2 weeks
* HF with dilated cardiomyopathy with allergic reaction and/or eosinophilia
41
How is myocarditis treated?
* Consult cardiology
* Treatment directed towards patient presentation
* LVEF <40% --> ACEI, BB
* NSAIDs for myopericardial chest pain
* Arrhythmia management
* Trials using immunosuppressive therapies, corticosteroids, IVIG, and antivirals have not shown benefit
42
What is most noninfectious myocarditis caused by?
* Medications
* Illicit drugs
* Toxic substances
43
How can patients with myocardial injury from toxic agents be managed?
* Monitored if LVEF (>40%) is preserved and no HF symptoms present
* If HF or LVEF ensues, managed by cardiology
44
What type of cardiomyopathy accounts for the majority of cases?
Dilated cardiomyopathy
45
Which population more commonly gets dilated cardiomyopathy?
Black patients
46
What is the prognosis of dilated cardiomyopathy once symptoms manifest?
mortality of 50% at 5 years
47
What are characteristics of dilated cardiomyopathy?
* Dilation and impaired contraction of one or both ventricles, predominantly the LV
* LVEF <40% without CAD or valvular disease
48
What is the etiology of dilated cardiomyopathy?
* Idiopathic
* Excessive alcohol consumption
* Infectious
* Genetic
* Systemic disorders
* Peripartum
* Endocrinopathies
* Tachycardia induced
* Arrhythmia associated
49
What are infectious causes of dilated cardiomyopathy?
Viral
* Parvo B19
* Herpes
* Coxsackievirus
* Influenza
* Adenovirus
* CMV
* HIV
Bacterial
* TB, meningococcal, pneumococcal
Chagas disease, lyme disease
50
What is chagas disease (causes dilated cardiomyopathy)?
* Protozoan infection
* Leading cause of DCM in central and south america
51
How does lyme disease usually manifest in dilated cardiomyopathy?
* conduction abnormality
* May cause myocardial dysfunction due to myocarditis
52
What are genetic causes of dilated cardiomyopathy?
* Autosomal dominant predominantly involves antibodies to cardiac proteins
* Inherited syndromes such as muscular dystrophies, hemochromotosis, thalassemias
53
What are systemic disorders that can cause dilated cardiomyopathies?
* Sarcoidosis
* SLE
* Celiac
* Scleroderma
* RA
54
What endocrine disorders can cause dilated cardiomyopathy?
* Thyroid dysfunction
* Pheochromocytoma
* Cushing's
* GH excess or deficiency
55
What arrhythmias can cause dilated cardiomyopathy?
* PVC mediated
* RV paced rhythm
56
What is the etiology of peripartum CM and how does it present?
* Unclear etiology
* Late in pregnancy or early postpartum
* Presents as CHF or SCA (sudden cardiac arrest)
* typically normalizes after 2 to 3 months of therapy
57
What are causes of tachycardia induced dilated cardiomyopathy?
* Afib, SVT, AVNRT
58
What is the pathophysiology of tachycardia induced dilated cardiomyopathy?
* HR correlates with LV dysfunction
* Reduced myocyte contractility
* LV dysfunction can occur without dilatation
59
What is the mneumonic for dilated cardiomyopathy etiology?
* A- alcohol
* Bunch of stuff: beriberi (wet)
* Can: Coxsackie B myocarditis
* Cause: Chronic cocaine use
* Cardiac: Chaga's disease
* Dilation: doxorubicin toxicity
## Footnote
beriberi heart disease is indistinguishable from DCM
60
What is the presentation of dilated cardiomyopathies?
* Gradual HF development
* Arrhythmias
* Sudden death possible
61
What is present on PE of dilated cardiomyopathy due to HF?
* Rales
* Elevated JVP
* S3 gallop
* Murmur of mitral or tricuspid regurg
* Peripheral edema
* Ascites
62
What arrhythmias can be caused by dilated cardiomyopathy?
* Tachycardia
* Pulsus alternans
* LBBB
63
How is dilated cardiomyopathy diagnosed?
* If dyspnea present, BNP or NT-proBNP to determine prognosis and severity
* Echo
* Possibly radionuclide ventriculography (MUGA), cardiac MRI
64
Why would a echo be helpful in dilated cardiomyopathy?
* Excludes valvular disease
* Confirms ventricular dilation, reduced LV systolic function (and RV systolic dysfunction if applicable), or pulmonary HTN
65
How is dilated cardiomyopathy treated?
* Treat underlying source if known, which commonly resolves LV dysfunction
* CHF management
* Prevention of SCA
* Heart transplant
66
What are characteristics of restrictive cardiomyopathy?
* Nondilated ventricle with impaired filling
* Caused by fibrosis or infiltration of ventricular wall
* Causes diastolic dysfunction
67
How does restrictive cardiomyopathy present on echo?
* Non-hypertrophied with moderate to severe biatrial enlargement
68
What are causes of restrictive cardiomyopathy?
* Infiltrative disorders: amyloidosis, sarcoidosis, fatty infiltration
* Storage diseases: hemochromatosis, fabry disease
* Radiation/chemo
* Carcinoid heart disease
* Hypereosinophilic syndrome
69
How is restrictive cardiomyopathy diagnosed?
* Echo or cardiac MRI
* Endomyocardial biopsy may be considered
70
How is restrictive cardiomyopathy treated?
* Treat underlying cause
* Reduce pulmonary and systemic congestion with diuretics
71
What causes hypertrophic cardiomyopathy?
mutations of sarcomere genes
autosomal dominant trait with variable penetrance
72
What are characteristics of hypertrophic cardiomyopathy?
* LV hypertrophy
* Occassionally RV involved
* Not caused by pathologic loading conditions, such as HTN and valvular disease
* Interventricular septum commonly prominently involved
* Leads to diastolic dysfunction
73
What can hypertrophic cardiomyopathy lead to?
* LV outflow obstruction, myocardial ischemia, and/or mitral regurgitation
74
What is the presentation of hypertrophic cardiomyopathy?
* Fatigue
* Chest pain
* CHF
* Syncope
* SCA
* Carotid pulsus bisferiens d/t mimicked aortic stenosis
* Increased risk for arrhythmias (afib, SVT, and VT/VF) and SCA
## Footnote
LISTEN FOR THIS MURMUR ON SPORTS PHYSICALS
75
What will hypertrophic cardiomyopathy murmur sound like?
* Mid-systolic
* Harsh
* 3rd and 4th intercostals
* Louder with valsalva
* Quieter with squatting
76
How is hypertrophic cardiomyopathy diagnosed?
* EKG with LVH pattern
* Echo = diagnostic of choice with LV wall > 1.5 cm thick
77
How is hypertrophic cardiomyopathy managed?
* Avoid volume depletion
* Activity restriction
* Beta-blockers or verapamil (helps relax contractility)
* Avoid diuretics and vasodilators (would decrease preload)
* Septal myectomy or alcohol septal ablation
* Screening of 1st degree relatives
78
How do you screen 1st degree relatives for hypertrophic cardiomyopathy?
* Annual echo until age 20 and then Q5 yrs
79
What is the most common cause of HF in the US?
Ischemic cardiomyopathy
80
What is the cause of ischemic cardiomyopathy?
* death/damage/hibernation of myocardium d/t reduced oxygen
* typically from CAD, but any ischemia can cause
* Cocaine, vasospasm, thrombus can also cause
81
What are characteristics of ischemic cardiomyopathy?
* transient or permanent systolic dysfunction
* predominantly affects LV, but can involve RV or both ventricles
82
What is the presentation of ischemic cardiomyopathy?
* CHF
* (edema, dyspnea, JVD)
83
How is ischemic cardiomyopathy diagnosed?
* Q waves on EKG possible
* CXR may reveal pulmonary edema
* Echo--> decreased LVEF, regional wall motion abnormality
* Coronary angiography recommended, especially if LV dysfunction cause unknown
84
How is ischemic cardiomyopathy managed?
* Revascularization (PCI or CABG) for acute ischemia/infarction
* Consider nuclear viability study to determine if myocardial dysfunction due to scarring or hibernating myocardium
* CHF management
* Prevention of SCA
* Cardiac rehab
85
How is SCA prevented in ischemic cardiomyopathy?
* External wearable defibrillator or implanted cardioverter-defibrillator
86
What are characteristics of arrhythmogenic right ventricular cardiomyopathy?
* Ventricular arrhythmias and specific myocardial pathology
* RV free wall myocardium replaced by fibrous/fatty tissue, producing RV dilation (leads to abnormal RV function)
87
Arrhythmogenic right ventricular cardiomyopathy is a important cause of death in which population?
Young adults
88
Where is arrhythmogenic right ventricular cardiomyopathy more prevalent?
Europe, rare in US
89
What is the presentation of arrhythmogenic right ventricular cardiomyopathy?
* Chest pain
* Palpitations
* Syncope
* SCA
90
How is arrhythmogenic right ventricular cardiomyopathy diagnosed?
* Echo and cardiac MRI
91
How is arrhythmogenic right ventricular cardiomyopathy managed?
* Manage systemic congestion with diuretics
* Manage ventricular arrhythmias with antiarrhythmics, ablation or ICD
92
What are the unclassified cardiomyopathys and their causes?
Left ventricular noncompaction
* Congenital
* Altered myocardial wall due to intrauterine arrest of compaction of loose interwoven meshwork
Stress-induced cardiomyopathy
* ACS (even STEMI) in absence of critical CAD, due to catecholamine surge bc of intense psychological or physical stress
93
What is the presentation of unclassified cardiomyopathy (left ventricular noncompaction)?
* CHF
* Thromboembolism
* Ventricular arrhythmias
94
How is left ventricular noncompaction diagnosed?
Cardiac MRI to confirm
95
How is left ventricular noncompaction treated?
Cardiac transplant
96
Which population more commonly gets stress-induced cardiomyopathy?
Postmenopausal women
97
How is stress-induced cardiomyopathy diagnosed?
LV apical ballooning on echo or LV angiography
98
How is stress-induced cardiomyopathy treated?
Almost all patients recover in a few weeks
* Treat with beta blockers for at least a year to try to prevent CV events
