NCLEX Review Guide: Cardiomyopathy

Dilated Cardiomyopathy (DCM)

• Most common type characterized by enlarged, weakened heart chambers with poor contractility and reduced ejection fraction (<30-40%).
• Common causes include alcohol abuse, viral infections, chemotherapy drugs (doxorubicin), and idiopathic factors.
• Presents with signs of heart failure: dyspnea, fatigue, peripheral edema, and decreased exercise tolerance.

Hypertrophic Cardiomyopathy (HCM)

• Genetic condition causing abnormal thickening of heart muscle, especially the interventricular septum, leading to outflow obstruction.
• Classic triad: dyspnea, chest pain, and syncope, particularly with exertion.
• High risk for sudden cardiac death in young athletes due to ventricular arrhythmias.

Restrictive Cardiomyopathy

• Least common type characterized by rigid, non-compliant ventricles that cannot fill properly during diastole.
• Caused by infiltrative diseases like amyloidosis, sarcoidosis, or hemochromatosis.
• Presents with right-sided heart failure symptoms: jugular vein distention, hepatomegaly, and ascites.

Common Signs and Symptoms

• Progressive dyspnea starting with exertion and advancing to rest, indicating worsening cardiac function.
• Chest pain may occur due to increased oxygen demand or coronary artery compression (especially in HCM).
• Fatigue and weakness from decreased cardiac output and poor tissue perfusion.
• Palpitations and arrhythmias, particularly atrial fibrillation and ventricular tachycardia.

Pharmacological Management

• ACE inhibitors/ARBs reduce afterload and prevent ventricular remodeling in DCM patients.
• Beta-blockers improve survival in DCM but must be started at low doses and titrated slowly.
• Diuretics manage fluid overload but monitor for electrolyte imbalances, especially potassium and magnesium.
• Avoid inotropes in HCM as they worsen outflow obstruction; use negative inotropes like beta-blockers instead.

1. Assess baseline vital signs, weight, and fluid status
2. Monitor daily weights (report gain >2-3 lbs in 24 hours)
3. Evaluate medication effectiveness and side effects
4. Educate patient on dietary sodium restriction (<2g/day)
5. Coordinate with cardiology for device therapy consideration

Lifestyle Modifications

• Activity restriction in HCM patients, especially avoiding competitive sports and strenuous exercise.
• Sodium restriction (<2g daily) and fluid limitation (1.5-2L daily) to prevent fluid overload.
• Alcohol cessation is crucial in alcohol-induced cardiomyopathy for potential reversibility.

Common Pitfalls

• Never give positive inotropes to HCM patients - this worsens outflow obstruction and can cause death.
• Don't confuse cardiomyopathy with myocarditis (inflammation) or pericarditis (outer layer inflammation).
• Sudden weight gain is more significant than gradual gain - indicates acute fluid retention.