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Cardiomyopathy, End Stage

Patients with end-stage cardiomyopathy have stage D heart failure or severe symptoms at rest refractory to standard medical therapy.System(s) affected: cardiovascular; renal Pediatric Considerations

Drugs and chemotherapy: anthracyclines, cyclophosphamide, Herceptin

para>Primary

  • Genetic
  • Hypertrophic cardiomyopathy (HCM)
  • Arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D)
  • Left ventricular (LV) noncompaction (LVNC)
  • Glycogen storage (Danon type, PRKAG2)
  • Conduction defects
  • Mitochondrial myopathies
  • Ion channel disorders: long QT syndrome, Brugada, short QT syndrome, catecholaminergic ventricular tachycardia (CVPT), Asian SUNDS
  • Mixed
  • Dilated cardiomyopathy (DCM) (genetic or nongenetic)
  • Restrictive
  • Acquired
  • Myocarditis, stress cardiomyopathy, peripartum, tachycardia-induced, infants of type 1 diabetic mothers

Secondary (see list below)

Specific

  • Ischemic
  • Valvular
  • Hypertensive
  • Congenital heart disease

Pediatric Considerations

Etiology: idiopathic, viral, congenital heart disease, and familial пїЅ

Pregnancy Considerations

May occur in women postpartum пїЅ

Epidemiology

Predominant age: Ischemic cardiomyopathy is the most common etiology; predominantly in patients aged >50 years. Consider uncommon causes in young. пїЅ

Incidence

  • 60,000 patients <65 years die each year from end-stage heart disease.
  • 35,000-70,000 people might benefit from cardiac transplant or chronic support.

Prevalence

Most rapidly growing form of heart disease пїЅ

Etiology and Pathophysiology

The most frequent causes are in bold: пїЅ

  • Ischemic heart disease: most common etiology; up to 66% of patients
  • Hypertension
  • Valvular heart disease
  • Primary genetic causes
  • Congenital heart disease
  • Peripartum/postpartum
  • EndocrineDiabetes mellitusHyperthyroidismHypothyroidismHyperparathyroidismPheochromocytomaAcromegaly
  • Nutritional deficienciesBeriberi, pellagra, scurvy, selenium, carnitine, kwashiorkor
  • Autoimmune/collagen
  • Infectious causesViral (e.g., HIV, coxsackievirus, adenovirus)Bacterial and mycobacterial (e.g., diphtheria, rheumatic fever)Parasitic (e.g., toxoplasmosis, Trypanosoma cruzi)
  • Infiltrative (2)AmyloidosisGaucher diseaseHurler diseaseHunter diseaseFabry disease
  • Storage
  • Neuromuscular/neurologic
  • ToxicAlcoholDrugs and chemotherapy: anthracyclines, cyclophosphamide, HerceptinRadiationHeavy metal, chemical agents
  • Inflammatory (granulomatous):
  • Idiopathic
  • Endomyocardial

Genetics

Autosomal dominant HCM is the most common form of primary genetic cardiomyopathy (1/500 in the general population). Genetic causes of DCM are less common, accounting for 1/3 cases, with mostly autosomal dominant inheritance. LNC and ARVC are also inherited in an autosomal dominant fashion in addition to LQTS and other ion-channel disorders. пїЅ

Risk Factors

  • Hypertension
  • Hyperlipidemia
  • Obesity
  • Coronary artery diease
  • Diabetes mellitus
  • Smoking
  • Physical inactivity
  • Excessive alcohol intake
  • Dietary sodium
  • Obstructive sleep apnea
  • Chemotherapy

General Prevention

Reduce salt and water intake; home BP and daily weight measurement пїЅ

Diagnosis

History

  • Dyspnea at rest or with exertion
  • Paroxysmal nocturnal dyspnea
  • Orthopnea
  • Postprandial dyspnea
  • Right upper quadrant pain or bloating
  • Midabdominal pain
  • Fatigue
  • Syncope
  • Edema

Physical Exam

  • Tachypnea
  • Cheyne-Stokes breathing
  • Low pulse pressure
  • Cool extremities
  • Jugular venous distention
  • Bibasilar rales
  • Tachycardia
  • Displaced point of maximal impulse (PMI)
  • S3 gallop
  • Blowing systolic murmur
  • Hepatosplenomegaly
  • Ascites
  • Edema

Differential Diagnosis

  • Severe pulmonary disease
  • Primary pulmonary hypertension
  • Recurrent pulmonary embolism
  • Constrictive pericarditis
  • Some advanced forms of malignancy
  • Anemia

Diagnostic Tests & Interpretation

  • ECG: LV hypertrophy, interventricular conduction delay, atrial fibrillation, evidence of prior Q-wave infarction
  • Hyponatremia
  • Prerenal azotemia
  • Anemia
  • Mild elevation in troponin
  • Elevated B-type natriuretic peptide (BNP) or pro-BNP
  • Mild hyperbilirubinemia
  • Elevated liver function tests
  • Elevated uric acid

Initial Tests (lab, imaging)

  • ECG
  • Chest radiograph
  • EchocardiographyIn dilated cardiomyopathy, 4-chamber enlargement and global hypokinesis are present.In hypertrophic cardiomyopathy, severe LV hypertrophy is present.Segmental contraction abnormalities of the LV are indicative of previous localized myocardial infarction.
  • Cardiac MRI
  • Myocardial stress perfusion imaging (MPI)

Diagnostic Procedures/Other

Cardiac catheterization пїЅ

  • Helpful to rule out ischemic heart disease
  • Characterize hemodynamic severity
  • Pulmonary artery catheters may be reasonable in patients with refractory heart failure to help guide management.

Treatment

See "Heart Failure, Chronic"пїЅ for detailed treatment protocols. пїЅ

General Measures

  • Reduction of filling pressures
  • Treatment of electrolyte disturbances

Medication

First Line

  • Systolic failure syndromesACE inhibitors: All considered equally effective; initiate at low doses and titrate as tolerated to target doses (3)[A].Loop diureticsFurosemide, 40-120 mg/day or TID (3)[A]β-BlockersMetoprolol succinate, 12.5-200 mg/day; carvedilol, 3.125-25 mg BID; or bisoprolol, 1.25-10 mg/day (3)[A]Patients with New York Heart Association (NYHA) II-IV heart failure, ejection fraction (EF) <35%, on standard therapy: aldosterone antagonists: spironolactone or eplerenone (3)[A]Digoxin, 0.125-0.25 mg/day for symptomatic patients on standard therapy (3)[B]Combination hydralazine/isosorbide dinitrate is 1st-line treatment in African American patients with class III-IV symptoms already on standard therapy and for all patients with reduced EF and symptoms incompletely responsive to ACE inhibitor and β-blocker (3)[A].β-Blockers: low cardiac output, 2nd- or 3rd-degree heart blockAvoid use of diltiazem and verapamil in patients with systolic dysfunction.Aldosterone antagonists: oliguria, anuria, renal dysfunctionLoop diuretics: hypokalemia, hypomagnesemiaACE inhibitors: pregnancy, angioedema
  • PrecautionsIn patients with chronic kidney disease, digoxin dosage should be ≤0.125 mg/day and drug levels followed carefully to avoid toxicity.Closely monitor electrolytes.ACE inhibitors: Initiate with care if BP is low. Begin with low-dose captopril, such as 6.25 mg TID.β-Blockers: Avoid in patients with evidence of poor tissue perfusion; they may further depress systolic function.Milrinone, dobutamine: long-term use associated with increased mortality
  • Medications TO AVOIDNSAIDsGlitazonesCilostazol

Second Line

  • Angiotensin receptor blockers as an alternative to ACE inhibitors
  • Inotropic therapy (e.g., dobutamine or milrinone) for cardiogenic shock and support prior to surgery or cardiac transplantation (3)[B]
  • Continuous inotrope infusion may be considered in stage D outpatients for symptom control in those who are not eligible for transplantation or mechanical circulatory support (3)[B].

Issues for Referral

Management by a heart failure team improves outcomes and facilitates early transplant referral. пїЅ

Additional Therapies

  • Prophylactic implantable cardioverter defibrillator (ICD) should be considered for patients with a left ventricular ejection fraction (LVEF) <35% and mild to moderate symptoms (3)[A].
  • Cardiac resynchronization therapy (CRT) is recommended and should be considered for patients in sinus rhythm with a QRS >150 msec, LVEF <35%, in FC I-III and ambulatory FC IV patients (3)[A].
  • Patients with severe, refractory heart failure with no reasonable expectation of improvement should not be considered for an ICD.
  • Consideration of an LV assist device as "permanent"пїЅ or destination therapy or cardiac transplantation is reasonable in selected stage D patients.

Ongoing Care

Diet

Low-fat, low-salt, fluid restriction пїЅ

Prognosis

~20-40% of patients in NYHA functional class IV die within 1 year. With a transplant, 1-year survival is as high as 94%. пїЅ

Complications

Worsening congestive heart failure syncope, renal failure, arrhythmias, or sudden death пїЅ

References

1.Maron пїЅBJ, Towbin пїЅJA, Thiene пїЅG, et al. Contemporary definitions and classification of the cardiomyopathies: an American Heart Association Scientific Statement from the Council on Clinical Cardiology, Heart Failure and Transplantation Committee; Quality of Care and Outcomes Research and Functional Genomics and Translational Biology Interdisciplinary Working Groups; and Council on Epidemiology and Prevention. Circulation. 2006;113(14):1807-1816. пїЅ[View Abstract]2.Seward пїЅJB, Casaclang-Verzosa пїЅG. Infiltrative cardiovascular diseases: cardiomyopathies that look alike. J Am Coll Cardiol. 2010;55(27):1769-1779. пїЅ[View Abstract]3.Yancy пїЅCW, Jessup пїЅM, Bozkurt пїЅB, et al. 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. 2013;128:1-375.

Additional Reading

See Also

Alcohol Abuse and Dependence; Alcohol Withdrawal; Amyloidosis; Congestive Heart Failure; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Hypertension, Essential; Hypothyroidism, Adult; Idiopathic Hypertrophic Subaortic Stenosis; Protein Energy Malnutrition; Rheumatic Fever; Sarcoidosis пїЅ

Codes

ICD10

  • I42.9 Cardiomyopathy, unspecified
  • I42.2 Other hypertrophic cardiomyopathy
  • I42.1 Obstructive hypertrophic cardiomyopathy
  • I43 Cardiomyopathy in diseases classified elsewhere
  • I42.4 Endocardial fibroelastosis
  • I42.5 Other restrictive cardiomyopathy
  • I42.8 Other cardiomyopathies
  • I42.6 Alcoholic cardiomyopathy
  • I42.3 Endomyocardial (eosinophilic) disease
  • I42.7 Cardiomyopathy due to drug and external agent
  • I42.0 Dilated cardiomyopathy

ICD09

  • 425.4 Other primary cardiomyopathies
  • 425.18 Other hypertrophic cardiomyopathy
  • 425.11 Hypertrophic obstructive cardiomyopathy
  • 425.8 Cardiomyopathy in other diseases classified elsewhere
  • 425.5 Alcoholic cardiomyopathy
  • 425.7 Nutritional and metabolic cardiomyopathy
  • 425.9 Secondary cardiomyopathy, unspecified

SNOMED

  • 85898001 Cardiomyopathy (disorder)
  • 233873004 Hypertrophic cardiomyopathy (disorder)
  • 45227007 Hypertrophic obstructive cardiomyopathy (disorder)
  • 195029002 Cardiomyopathy associated with another disorder (disorder)
  • 83521008 Dilated cardiomyopathy secondary to alcohol (disorder)
  • 399020009 Congestive cardiomyopathy (disorder)
  • 415295002 Restrictive cardiomyopathy (disorder)
  • 195023001 Nutritional and metabolic cardiomyopathies (disorder)
  • 89461002 Primary cardiomyopathy

Clinical Pearls

  • Cardiomyopathy represents the end-stage of a large number of disease processes involving the heart muscle.
  • Ischemic, hypertensive, postviral, familial, alcoholic, and incessant tachycardia-induced are the most common cardiomyopathy varieties seen in the United States.
  • Core therapy for heart failure applies: salt restriction, diuretics, ACE inhibitors, β-blockers, digoxin, and electrical treatments, such as cardiac resynchronization and implantable defibrillators, as appropriate.