Dilated cardiomyopathy resident survival guide
|Dilated cardiomyopathy resident survival guide Microchapters|
Dilated cardiomyopathy (DCM) relates to a group of heterogeneous myocardial disorders and is characterized by dilatation and impaired contraction and systolic function of the left or both ventricles. Atrial and/or ventricular arrhythmias can occcur, and there is a risk for sudden death.  The weight of the heart assessed by the MRI and echocardiogram is increased but the maximal thicknesses of the left ventricular free wall and septum are usually normal as a result of the abnormally dilated chambers. Dilated cardiomyopathy is treated the same way that congestive heart failure is.
Life-threatening causes include conditions which may result in death or permanent disability within 24 hours if left untreated.
- Life-threatening causes:
- Common causes:
FIRE: Focused Initial Rapid Evaluation
A Focused Initial Rapid Evaluation (FIRE) should be performed to identify patients with signs and symptoms of severe acute decompensated heart failure who require immediate intervention.
Boxes in red signify that an urgent management is needed.
BU: Blood urea nitrogen;
COPD: Chronic obstructive pulmonary disease;
D5W: 5% dextrose solution in water ;
HF: Heart failure;
MAP: Mean arterial pressure;
NSAID: Non steroidal anti-inflammatory drug;
SBP: Systolic blood pressure;
S3: Third heart sound;
Identify cardinal findings that increase the pretest probability of acute decompensated heart failure
Does the patient have any of the following findings that require hospitalization and urgent management?
❑ Severe decompendated HF:
Admit to a level of care that allows for constant ECG monitoring
|Proceed to complete diagnostic approach|
NPPV is contraindicated in cardiorespiratory arrest, glasgow coma scale < 10 or no patient cooperation, severe upper GI bleeding, hemodynamic instability, facial injury, upper airway obstruction, or high aspiration risk
❑ Titrate oxygen delivery to maintain SpO2 >90%
Assess Congestion and Perfusion
❑ Cold and wet
Identify Precipitating Factors and Treat Accordingly
Click on the precipitating factor for more details on the management
Manage the Patient's Acute Symptoms
Relieve Congestiona and Improve Volume Status
❑ Maintain a low sodium diet (<2 g daily)
❑ Consider low dose dopamine infusion for improved diuresis and renal blood flow (IIb-B)
Maintenance of Diuresis
❑ Monitor urine output to achieve goal urine output > 100 mL/hour.
Manage Low Perfusion / Low Output
❑ Monitor vital signs continuously during administration of inotropic agents
Consider Invasive Hemodynamic Monitoring
❑ DO NOT INITIATE ACEI/ARBs during an acute decompensation
|Proceed to complete diagnostic approach|
Complete Diagnostic Approach
A complete diagnostic approach should be carried out after a focused initial rapid evaluation is conducted and following initiation of any urgent intervention.
|Symptoms of heart failure|
History and symptoms:
❑ Hints for etiology (at least 3 generations of family history, and others)
❑ Vital signs:
❑ General appearance:
❑ Complete blood count
Imaging and additional tests:
❑ Noninvasive imaging:
❑ Invasive imaging: Consider invasive Imaging only in specific cases.
Examples for specific findings for dilated cardiomyopathy:
❑ Echo (dilated left and/or right ventricle, global hypokinesis with left ventricular ejection fraction under 40%
|Consider endomyocardial biopsy||Treat with conventional heart failure medications|
|Clinical improvement after 1 week?|
|Continue conventional heart failure treatment||Consider endomyocardial biopsy|
- The initial diagnostic approach should aim to identify potentially reversible causes of left ventricular dysfunction. Pertinent history includes alcohol consumption, recent viral illness, coronary risk factors, and family history.
- Endomyocardial biopsy should not be performed in the routine evaluation of patients with HF. Optimal timing of endomyocardial biopsy for patients unresponsive to medical therapy remains unclear.
- Nondihydropyridine calcium channel blockers with negative inotropic effects may be harmful in asymptomatic patients with low LVEF and no symptoms of HF after MI.
- "Report of the WHO/ISFC task force on the definition and classification of cardiomyopathies". Br Heart J. 44 (6): 672–3. 1980. PMC 482464. PMID 7459150.
- Tazelaar HD, Billingham ME (1986). "Leukocytic infiltrates in idiopathic dilated cardiomyopathy. A source of confusion with active myocarditis". Am J Surg Pathol. 10 (6): 405–12. PMID 3521345.
- Felker GM, Thompson RE, Hare JM, Hruban RH, Clemetson DE, Howard DL; et al. (2000). "Underlying causes and long-term survival in patients with initially unexplained cardiomyopathy". N Engl J Med. 342 (15): 1077–84. doi:10.1056/NEJM200004133421502. PMID 10760308.
- Yancy CW, Jessup M, Bozkurt B, Butler J, Casey DE, Drazner MH; et al. (2013). "2013 ACCF/AHA guideline for the management of heart failure: executive summary: a report of the American College of Cardiology Foundation/American Heart Association Task Force on practice guidelines". Circulation. 128 (16): 1810–52. doi:10.1161/CIR.0b013e31829e8807. PMID 23741057.
- Yancy, C. W.; Jessup, M.; Bozkurt, B.; Butler, J.; Casey, D. E.; Drazner, M. H.; Fonarow, G. C.; Geraci, S. A.; Horwich, T.; Januzzi, J. L.; Johnson, M. R.; Kasper, E. K.; Levy, W. C.; Masoudi, F. A.; McBride, P. E.; McMurray, J. J. V.; Mitchell, J. E.; Peterson, P. N.; Riegel, B.; Sam, F.; Stevenson, L. W.; Tang, W. H. W.; Tsai, E. J.; Wilkoff, B. L. (2013). "2013 ACCF/AHA Guideline for the Management of Heart Failure: A Report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines". Circulation. 128 (16): e240–e327. doi:10.1161/CIR.0b013e31829e8776. ISSN 0009-7322.
- WRITING COMMITTEE MEMBERS. Yancy CW, Jessup M, Bozkurt B, Butler J, Casey DE; et al. (2013). "2013 ACCF/AHA guideline for the management of heart failure: a report of the American College of Cardiology Foundation/American Heart Association Task Force on practice guidelines". Circulation. 128 (16): e240–327. doi:10.1161/CIR.0b013e31829e8776. PMID 23741058.