Cardiomyopathy nursing: HOCM, Takotsubo, and dilated cardiomyopathy care

Introduction

Cardiomyopathy refers to disease of the heart muscle that impairs the heart’s ability to pump blood effectively. Unlike structural heart disease caused by valve problems or coronary artery blockages, cardiomyopathy originates within the myocardium itself – affecting its size, shape, thickness, or function. This page covers the four types most often tested in nursing school: dilated, hypertrophic, restrictive, and Takotsubo. Each has distinct pathophysiology, clinical presentation, and management.

The 2023 European Society of Cardiology (ESC) guideline classifies cardiomyopathies by phenotype: hypertrophic (HCM), dilated (DCM), non-dilated left ventricular cardiomyopathy (NDLVC), arrhythmogenic right ventricular cardiomyopathy (ARVC), and restrictive (RCM). The ESC treats each phenotype as the first step toward a specific cause, which is often genetic, and recommends genetic testing for patients with cardiomyopathy. ARVC, where fibrofatty tissue replaces right ventricular muscle and causes ventricular arrhythmias, is covered in the HRS consensus statement on arrhythmogenic cardiomyopathy. Takotsubo is not one of the five ESC phenotypes; the 2006 AHA classification lists it as an acquired cardiomyopathy.

Understanding cardiomyopathy is essential for NCLEX success and clinical practice. These conditions are common causes of heart failure, sudden cardiac death, atrial fibrillation, and cardiac transplantation. Each type carries specific nursing priorities – and in hypertrophic cardiomyopathy, the wrong intervention can be lethal.

Cardiomyopathy quick reference

Dilated cardiomyopathy (DCM)

Pathophysiology

In dilated cardiomyopathy, one or both ventricles become enlarged and weakened. The left ventricle – most commonly affected – dilates under the stress of progressive systolic dysfunction, reducing ejection fraction (EF) and cardiac output. As the chamber expands, wall tension increases per the law of Laplace, further impairing contractility. The mitral valve annulus stretches with ventricular dilation, causing functional mitral regurgitation that further reduces forward flow.

The result is a heart that pumps less blood per beat, compensates initially through neurohormonal activation (sympathetic nervous system, RAAS), but ultimately decompensates into the clinical syndrome of heart failure with reduced ejection fraction (HFrEF). The ESC defines the DCM phenotype as LV dilation with systolic dysfunction (LVEF below 50%) that is not explained by abnormal loading conditions or coronary artery disease.

Causes

In guideline terms, DCM is a non-ischemic diagnosis. Coronary artery disease is the most common cause of a dilated, poorly contracting LV in the United States, but that picture is called ischemic cardiomyopathy and is managed as ischemic HFrEF. For nursing students, the clinical point still holds: a patient with a history of MI presenting with worsening dyspnea and peripheral edema should prompt consideration of ischemic LV dysfunction. See the MI/ACS nursing reference for the ischemic pathway.

Non-ischemic causes of DCM include:

• Genetic/familial – variants in genes such as titin (TTN, a sarcomeric protein) and lamin A/C (LMNA, a nuclear envelope protein); lamin A/C variants carry a high risk of conduction disease and ventricular arrhythmias. The ESC recommends genetic testing for patients with cardiomyopathy and screening of first-degree relatives
• Idiopathic – historically about half of non-ischemic cases had no identified cause; genetic testing and cardiac MRI now explain a growing share
• Alcohol – chronic excess leads to direct myocardial toxicity; among the most reversible causes if alcohol is stopped
• Viral myocarditis – myocarditis (viral causes, and Chagas disease from Trypanosoma cruzi) can progress to DCM as the post-inflammatory phase causes fibrosis and remodeling
• Peripartum cardiomyopathy – LV systolic dysfunction (LVEF nearly always below 45%) presenting toward the end of pregnancy or in the months after delivery, mostly in the first month postpartum, with no other cause found. Risk factors include older maternal age, multiparity, preeclampsia, and African descent; a genetic contribution is present in up to 20% of cases
• Toxic – anthracycline chemotherapy (dose-dependent), cocaine, methamphetamines
• Endocrine – thyroid disease, acromegaly, pheochromocytoma

Clinical presentation

• Dyspnea – on exertion initially, progressing to rest; orthopnea and paroxysmal nocturnal dyspnea with worsening HF
• Fatigue – reduced cardiac output limits oxygen delivery to skeletal muscle
• S3 gallop – a classic sign of volume overload and a dilated, failing LV in adults (it can be normal in children, young adults, and pregnancy); heard best at the cardiac apex with the bell
• Displaced PMI (point of maximal impulse) – the enlarged LV shifts the apex beat laterally beyond the mid-clavicular line; a key NCLEX physical exam finding
• Peripheral edema – bilateral, dependent; from elevated venous pressure and neurohormonal fluid retention
• JVD – elevated jugular venous distension reflecting right-sided pressure elevation
• Crackles – pulmonary edema as pulmonary venous hypertension causes fluid transudation into alveoli
• Functional mitral regurgitation – holosystolic murmur from annular dilation; may be audible

Management

Standard guideline-directed medical therapy (GDMT) for HFrEF applies. The 2022 AHA/ACC/HFSA heart failure guideline and the ESC both build it on four drug classes:

• ARNI (sacubitril/valsartan) – recommended for NYHA class II–III HFrEF to reduce morbidity and mortality; an ACE inhibitor (or an ARB if ACE inhibitors are not tolerated) is used when an ARNI is not feasible. Allow a 36-hour washout after the last ACE inhibitor dose before starting an ARNI, because the combination raises angioedema risk
• Beta-blockers – reduce sympathetic drive, lower heart rate, prevent arrhythmias, reverse remodeling; carvedilol, metoprolol succinate, and bisoprolol are the evidence-based choices
• Mineralocorticoid receptor antagonists – spironolactone or eplerenone for HFrEF with NYHA class II–IV symptoms, if eGFR is above 30 mL/min/1.73 m² and potassium is below 5.0 mEq/L; reduce mortality and hospitalizations
• SGLT2 inhibitors – dapagliflozin, empagliflozin; reduce HF hospitalizations and cardiovascular death regardless of diabetes status
• Loop diuretics – furosemide or bumetanide for congestion; symptom relief with no proven mortality benefit
• ICD – for LVEF ≤35% with NYHA class II–III symptoms despite at least 3 months of GDMT, when survival beyond 1 year is expected; primary prevention of sudden cardiac death. The ESC adds that some genetic forms (such as lamin A/C variants) may warrant an ICD even when LVEF is above 35%
• CRT (cardiac resynchronization therapy) – for LVEF ≤35%, sinus rhythm, LBBB with QRS ≥150 ms, and NYHA class II–IV symptoms on GDMT; improves symptoms, EF, and survival
• Heart transplantation – for refractory end-stage disease; considered when EF remains severely reduced despite optimal therapy

See the heart failure nursing reference for detailed HFrEF management, diuretic dosing, and monitoring protocols.

Hypertrophic cardiomyopathy (HCM / HOCM)

Pathophysiology

Hypertrophic cardiomyopathy is one of the most common inherited cardiac diseases. Unexplained hypertrophy has been reported in about 1 in 500 young US adults, and the 2024 AHA/ACC guideline notes that the true burden is higher than the number of diagnosed cases. HCM is usually inherited in an autosomal dominant pattern (each child of an affected parent has a 50% chance of inheriting the variant), but a family history is not required for the diagnosis. It is caused by mutations in genes encoding sarcomeric proteins – most commonly myosin heavy chain (MYH7) and myosin-binding protein C (MYBPC3). These mutations cause disordered, disorganized cardiomyocyte architecture (myocardial disarray), abnormal calcium handling, and pathological hypertrophy – particularly of the interventricular septum.

The asymmetric septal hypertrophy narrows the left ventricular outflow tract (LVOT). During systole, the high-velocity blood flow through the narrowed LVOT creates a Venturi effect that draws the anterior mitral valve leaflet toward the septum – this is systolic anterior motion (SAM) of the mitral valve. SAM worsens LVOT obstruction and causes mitral regurgitation. The degree of obstruction fluctuates dynamically based on loading conditions: reduced preload (less blood in the ventricle) worsens obstruction; increased preload (more filling) reduces it.

The ventricle is thick and non-compliant, producing diastolic dysfunction even when systolic function is preserved. The hyperdynamic LV ejects blood with abnormally high force – EF is often supranormal (>70%).

When obstruction is present at rest or with provocation, the condition is termed hypertrophic obstructive cardiomyopathy (HOCM), or obstructive HCM. Obstruction is defined as a peak LVOT gradient of 30 mm Hg or more, and a gradient of 50 mm Hg or more is generally considered capable of causing symptoms. Approximately 70% of HCM patients have some degree of LVOT obstruction at rest or with provocation.

HCM and sudden cardiac death in young athletes

The 2024 AHA/ACC guideline describes HCM as one of the most common causes of sudden cardiac death (SCD) in young people in North America. In a US registry of 1,866 sudden deaths in young competitive athletes (1980–2006), HCM was the most common cardiovascular cause, at 36% of cardiovascular deaths, followed by congenital coronary artery anomalies (17%). Younger patients with HCM carry higher SCD risk than older patients. The mechanism is ventricular fibrillation, triggered by the combination of myocardial disarray (arrhythmogenic substrate), dynamic LVOT obstruction reducing coronary perfusion during exertion, and exercise-induced catecholamine surges. Athletes can die during or immediately after exercise – often with no prior symptoms.

Clinical presentation

• Dyspnea on exertion – the most common symptom; from diastolic dysfunction, elevated filling pressures, and outflow obstruction
• Syncope – particularly exertional syncope; results from inadequate cardiac output with LVOT obstruction or arrhythmia; an important red flag for SCD risk
• Chest pain (angina) – in the absence of obstructive CAD; caused by increased myocardial oxygen demand from hypertrophy combined with impaired coronary microvascular perfusion
• Palpitations – from supraventricular or ventricular arrhythmias; atrial fibrillation complicates HCM in 20–25% of cases and is particularly dangerous because loss of atrial kick dramatically worsens filling of the non-compliant LV
• Harsh systolic murmur – best heard at the left sternal border; crescendo-decrescendo (ejection type); this murmur is dynamic and responds predictably to maneuvers that change preload or afterload

The HOCM murmur and Valsalva – the most tested NCLEX fact

The HOCM murmur increases with maneuvers that decrease preload (less blood in the LV = more obstruction). In a classic bedside study (Lembo 1988), a louder murmur with Valsalva was 96% specific for HCM, though only 65% sensitive; squat-to-stand was 95% sensitive and 84% specific:

• Valsalva maneuver (forced exhalation against a closed glottis) → decreases venous return → reduces LV filling → worsens LVOT obstruction → murmur gets louder
• Standing from squatting → decreases venous return → same mechanism
• Squatting from standing → increases venous return → more LV filling → less obstruction → murmur gets softer
• Passive leg raise → increases preload → murmur decreases

This is opposite to aortic stenosis and most other systolic murmurs, which become softer with Valsalva. The one other murmur that commonly behaves this way is mitral valve prolapse, whose click and murmur move earlier and lengthen when standing or straining.

What to avoid in HOCM

The 2024 AHA/ACC guideline calls positive inotropes, pure vasodilators, and high-dose diuretics relatively contraindicated in symptomatic obstructive HCM, because they reduce preload or afterload or increase contractility, worsen LVOT obstruction, and can precipitate hypotension:

• Vasodilators – nitrates, dihydropyridine calcium channel blockers, ACE inhibitors, and ARBs reduce afterload and preload, increasing the outflow gradient; the guideline suggests stopping them in obstructive HCM where possible
• High-dose diuretics and aggressive diuresis – reduce preload; less LV filling worsens obstruction. Cautious low-dose oral diuretics may be considered for persistent congestion despite other HCM therapy
• Digoxin – a positive inotrope that can worsen the dynamic obstruction; stopping it is reasonable in obstructive HCM
• Positive inotropes – dobutamine, epinephrine, dopamine, milrinone
• Dehydration and heat – the guideline advises patients with obstructive physiology to stay hydrated and avoid extreme heat and humidity

For acute hypotension in obstructive HCM, give IV fluids first. If hypotension does not respond to fluids, IV phenylephrine (or another vasoconstrictor without inotropic activity), alone or with a beta-blocker, is recommended (class 1).

Management

• Beta-blockers – first-line; the guideline recommends non-vasodilating beta-blockers titrated to effect or the maximum tolerated dose. They reduce heart rate (increasing filling time), decrease contractility (reducing obstruction), and are antiarrhythmic; metoprolol, propranolol, and nadolol are common choices
• Non-dihydropyridine calcium channel blockers – verapamil or diltiazem when beta-blockers are ineffective or not tolerated; verapamil is potentially harmful with severe dyspnea at rest, hypotension, or very high resting gradients (above 100 mm Hg), and in infants under 6 weeks
• Disopyramide – negative inotrope added (with an AV nodal blocking drug) for persistent symptoms
• Cardiac myosin inhibitors – mavacamten (Camzyos) and aficamten (Myqorzo) reduce excess sarcomeric contractility to relieve LVOT obstruction. Both are FDA-approved for adults with symptomatic obstructive HCM (the mavacamten label specifies NYHA class II–III). The 2024 AHA/ACC/AMSSM/HRS/PACES/SCMR guideline recommends a myosin inhibitor, disopyramide, or septal reduction therapy at an experienced center when beta-blockers or verapamil/diltiazem do not control symptoms (aficamten was approved after that guideline). Both drugs lower ejection fraction and carry a boxed warning for heart failure from systolic dysfunction, so each is available only through a REMS program with echocardiograms before and during treatment. Starting either drug is not recommended if LVEF is below 55%. Mavacamten is interrupted if LVEF falls below 50%, while aficamten is dose-reduced at LVEF 40–49% and interrupted below 40%. Both have significant CYP drug interactions, and the 2024 guideline lists mavacamten as contraindicated in pregnancy because of potential teratogenic effects
• ICD implantation – for secondary prevention after cardiac arrest or sustained ventricular arrhythmia, and for primary prevention in adults with one or more major risk factors: family history of HCM-related sudden death in a close relative aged 50 or younger, massive LV hypertrophy (wall thickness ≥30 mm), unexplained syncope thought to be arrhythmic, LV apical aneurysm, or LVEF below 50%. NSVT on ambulatory monitoring and extensive late gadolinium enhancement on cardiac MRI help when the decision is uncertain. SCD risk is reassessed every 1–2 years
• Exercise and sports – current AHA/ACC guidance has moved away from a blanket sports ban. Mild- to moderate-intensity recreational exercise is recommended for most patients (class 1), and universal restriction from vigorous activity or competitive sports is not indicated (class 3: no benefit). Vigorous recreational activity is reasonable, and competitive sports may be considered, after an annual expert evaluation and shared decision-making that covers the possible increase in SCD and ICD-shock risk
• Septal myectomy – surgical removal of a portion of the hypertrophied septum; gold standard for symptom-refractory LVOT obstruction; performed at specialized HCM centers
• Alcohol septal ablation – catheter-based technique; alcohol injected into a septal perforator artery creates a controlled infarct, thinning the septum; less invasive than surgery but higher rate of complete heart block

Restrictive cardiomyopathy

Pathophysiology

Restrictive cardiomyopathy is the least common of the primary cardiomyopathies. The ventricles are small to normal in size with normal or near-normal wall thickness but become abnormally stiff – unable to relax and fill adequately during diastole. The fundamental problem is diastolic dysfunction: the stiff myocardium resists filling, causing elevated filling pressures with preserved (or only mildly reduced) systolic function.

The consequence is a heart that cannot accommodate adequate ventricular volume at normal filling pressures. To maintain stroke volume, filling pressures rise – producing elevated venous pressures on both sides: elevated right-sided pressure causes JVD, hepatomegaly, ascites, and peripheral edema; elevated left-sided pressure causes pulmonary venous hypertension and dyspnea.

Restrictive cardiomyopathy is preload-dependent: the stiff ventricle requires adequate filling pressure to generate sufficient stroke volume. Volume depletion – from over-diuresis or bleeding – can cause profound reduction in cardiac output.

Causes

Unlike DCM or HCM, restrictive cardiomyopathy is almost always secondary to an infiltrative or fibrotic process that replaces or stiffens normal myocardial architecture:

• Cardiac amyloidosis – the most clinically important cause; abnormal protein (amyloid) deposits infiltrate the myocardium. Classic findings: “sparkling” or granular appearance on echocardiography, low-voltage ECG despite thickened walls (amyloid dampens electrical signals), elevated BNP disproportionate to LV size. Two main subtypes: AL amyloidosis (light chain, from plasma cell dyscrasia) and ATTR amyloidosis (transthyretin, hereditary or wild-type/“senile”)
• Sarcoidosis – non-caseating granulomas infiltrate the myocardium; high risk of complete heart block and ventricular tachycardia; can mimic pericarditis or myocarditis
• Hemochromatosis – iron deposition in cardiomyocytes; presents with HF, arrhythmias, and conduction defects; potentially reversible with phlebotomy or chelation if detected early
• Radiation fibrosis – mediastinal radiation (e.g., for lymphoma or breast cancer) causes progressive myocardial and pericardial fibrosis over years
• Endomyocardial fibrosis – tropical disorder affecting the endocardial layer
• Storage diseases – Fabry disease (a lysosomal sphingolipid storage disorder) and glycogen storage diseases such as Pompe disease cause intracellular substrate accumulation; Fabry more often produces a hypertrophic than a restrictive picture

Clinical presentation

Patients present with signs and symptoms of biventricular heart failure with preserved ejection fraction (HFpEF):

• Progressive dyspnea, orthopnea, and reduced exercise tolerance
• Markedly elevated JVP – one of the most prominent findings; the elevated venous pressure from impaired RV filling manifests as prominent jugular venous distension
• Kussmaul’s sign – paradoxical rise in JVP with inspiration (normal JVP falls with inspiration); results from the right ventricle’s inability to accommodate the increased venous return that occurs during inhalation; classically associated with restrictive cardiomyopathy and constrictive pericarditis
• Peripheral edema, ascites, and hepatomegaly from chronic venous hypertension
• Fatigue from low cardiac output
• Arrhythmias – particularly complete heart block in sarcoidosis and hemochromatosis

Management

There is no specific treatment for most restrictive cardiomyopathies. The goals are managing volume overload, treating the underlying cause where possible, and preventing complications:

• Treat the underlying cause: Phlebotomy or chelation for hemochromatosis; immunosuppression for sarcoidosis; for ATTR amyloidosis, the transthyretin stabilizers tafamidis (Vyndaqel/Vyndamax) and acoramidis (Attruby) or the TTR-silencing drug vutrisiran (Amvuttra), all FDA-approved for ATTR cardiomyopathy to reduce cardiovascular death and hospitalization; chemotherapy for AL amyloidosis
• Diuretics – used cautiously; these patients are highly preload-dependent, and over-diuresis causes significant reduction in cardiac output and hemodynamic compromise
• Rate control – atrial fibrillation is common; controlling ventricular rate preserves filling time, which is already impaired by diastolic dysfunction
• Anticoagulation – for atrial fibrillation given high thromboembolic risk
• Avoid vasodilators – the stiff ventricle cannot compensate for reduced afterload with increased filling
• Heart transplantation – may be considered in younger patients with end-stage disease, though amyloidosis recurrence in the transplanted heart is a concern with AL type

The distinction between restrictive cardiomyopathy and constrictive pericarditis is clinically important because constrictive pericarditis is surgically curable. Both share Kussmaul’s sign and similar hemodynamics; cardiac MRI, CT, and hemodynamic catheterization are used to differentiate them. See pericarditis nursing for the pericardial differential.

Takotsubo (stress/apical ballooning) cardiomyopathy

Pathophysiology

Takotsubo cardiomyopathy – also called stress cardiomyopathy or apical ballooning syndrome – is a transient, reversible form of ventricular dysfunction triggered by a sudden catecholamine surge. The condition is named for the Japanese octopus trap (takotsubo), whose shape resembles the characteristic appearance of the ballooned LV apex on ventriculography.

The trigger is emotional or physical stress: sudden grief, fright, medical procedures, natural disasters, or severe physiological illness (sepsis, stroke, intracranial hemorrhage). In the International Takotsubo Registry (1,750 patients), physical triggers (36.0%) were more common than emotional ones (27.7%), and 28.5% of patients had no evident trigger. The catecholamine surge is believed to cause direct myocardial toxicity and microvascular dysfunction, producing transient dysfunction predominantly in the apical segments of the LV – while the basal segments contract normally or even hypercontract. One explanation for the apical pattern: beta-adrenergic receptor density in the LV is highest at the apex, which may make the apex more sensitive to very high catecholamine levels.

On echocardiography or left ventriculography, the apex appears dyskinetic and ballooned while the base contracts normally – the inverse of what is seen in typical MI patterns (which follow coronary territory). Coronary angiography shows no culprit lesion that explains the wall motion pattern (coexisting coronary disease does not rule Takotsubo out), which distinguishes Takotsubo from STEMI – though the two are often clinically indistinguishable on initial presentation.

Clinical profile

• Demographics: Predominantly post-menopausal women (89.8% female, mean age 66.8 years in the International Takotsubo Registry); the drop in estrogen may reduce catecholamine protection in the microvasculature
• Trigger: An identifiable physical or emotional stressor in about 7 of 10 cases – acute medical illness, medical procedure, death of a loved one, major accident, argument
• Presentation: Sudden-onset chest pain and dyspnea; often indistinguishable from STEMI at initial presentation – ST-segment elevation on ECG, troponin elevation, wall motion abnormalities on echo
• Troponin: Mildly elevated – the degree of troponin elevation is disproportionately low relative to the extent of wall motion abnormality (unlike true MI, where larger territory infarction produces higher troponin peaks)
• Coronary angiogram: No culprit coronary lesion matching the wall motion abnormality; the apical ballooning pattern on left ventriculography supports the diagnosis

Clinical course and management

Takotsubo is generally a reversible condition. LV contractility typically recovers completely within 4–8 weeks with supportive care. However, the acute phase carries real risk: in the International Takotsubo Registry, rates of severe in-hospital complications, including shock and death, were similar to those of matched acute coronary syndrome patients. Cardiogenic shock, LV outflow tract obstruction (found in about 20% of patients evaluated for shock), LV thrombus, QT prolongation with torsades de pointes, and AV block can all occur.

• Supportive care – the foundation; most patients recover without specific intervention
• ACE inhibitors or ARBs – associated with better 1-year survival and fewer recurrences in registry data
• Beta-blockers – the InterTAK consensus calls them reasonable until LVEF recovers, but trial evidence is lacking, registry data showed no survival benefit, and they did not appear to prevent recurrence. They are contraindicated in acute severe heart failure with low LVEF, hypotension, or bradycardia, and need caution with a prolonged QT interval
• Anticoagulation – LV thrombus can form in the akinetic apex. Heparin is appropriate for confirmed thrombus and is reasonable with severe LV dysfunction and extensive apical ballooning; anticoagulation after discharge is decided case by case
• Limit catecholamines – patients given catecholamine drugs had about 20% mortality in reported series (partly because sicker patients receive them), and inotropes can provoke LVOT obstruction in apical ballooning. Patients in shock should be checked for LVOT obstruction by echo. The consensus names levosimendan (not available in the US) as an alternative inotrope, and mechanical circulatory support is used for refractory shock
• Recurrence – about 5% of survivors have a second episode, usually between 3 weeks and 3.8 years after the first; recurrence can follow a different trigger and ballooning pattern

Because Takotsubo mimics STEMI, patients go for emergent catheterization, and the consensus advises treating them as ACS (aspirin, heparin) until angiography. Finding no culprit lesion points toward Takotsubo; it does not mean the heart is undamaged. In the acute phase, nursing priorities mirror ACS care: continuous telemetry with QT monitoring, hemodynamic assessment for shock, and follow-up echocardiography. See the MI/ACS nursing reference for parallel management priorities.

HOCM vs DCM comparison

Nursing priorities by type

Complications across cardiomyopathy types

All cardiomyopathy types share common downstream complications, though the mechanisms and timing differ:

Atrial fibrillation – a major complication of all cardiomyopathy types. In DCM, left atrial enlargement from elevated filling pressures predisposes to AFib. In HOCM, the non-compliant LV is particularly dependent on atrial kick for filling – AFib causes rapid hemodynamic deterioration. In restrictive cardiomyopathy, elevated filling pressures chronically dilate both atria. AFib in any cardiomyopathy patient warrants rate control, rhythm management, and anticoagulation evaluation. In HCM, the 2024 AHA/ACC guideline recommends anticoagulation for clinical AF regardless of CHA₂DS₂-VASc score, with a direct oral anticoagulant as first choice. Review the atrial fibrillation nursing reference for management protocols.

Heart failure – the shared clinical endpoint across all types. DCM produces HFrEF; HOCM and restrictive cardiomyopathy produce HFpEF physiology; Takotsubo can cause transient HF or cardiogenic shock. Nurses caring for any cardiomyopathy patient must be competent in heart failure nursing assessment and intervention.

Sudden cardiac death – a central risk in HCM (higher in younger patients) and in DCM, especially with LVEF ≤35% or high-risk genetic variants such as lamin A/C. Risk stratification and ICD consideration are fundamental to the long-term management of both.

Thromboembolic events – sluggish blood flow in a dilated, poorly contracting LV (DCM) or akinetic apical segment (Takotsubo) creates thrombus. Embolization causes stroke, systemic embolism, and organ infarction.

Infective endocarditis – structural cardiac disease and indwelling devices (ICDs, LVADs) increase the risk of endocarditis. See the infective endocarditis nursing reference for prevention and recognition.

Medication interactions and pharmacology – cardiomyopathy patients are on complex multi-drug regimens. The cardiovascular medications nursing reference covers ACE inhibitors, beta-blockers, loop diuretics, mineralocorticoid antagonists, and antiarrhythmics in depth.

NCLEX tips

• HOCM murmur increases with Valsalva and standing – reduced preload worsens LVOT obstruction, making the murmur louder. Most other systolic murmurs, including aortic stenosis, get softer with Valsalva; mitral valve prolapse is the other common exception. If an NCLEX item describes a harsh systolic murmur that gets louder with Valsalva or standing and softer with squatting, think HCM.

• Avoid vasodilators, digoxin, inotropes, and high-dose diuretics in obstructive HCM – reducing preload or afterload, or increasing contractility, worsens LVOT obstruction and can cause hypotension. The 2024 AHA/ACC guideline calls these relatively contraindicated in symptomatic obstructive HCM. Low-dose diuretics may be used cautiously for congestion. For hypotension, give IV fluids first, then phenylephrine (a pure vasoconstrictor).

• Displaced PMI in DCM – the apex beat is shifted laterally beyond the mid-clavicular line due to LV dilation. This is a physical exam finding NCLEX tests as a distinguishing feature of DCM.

• S3 gallop signals volume overload – an S3 heard at the apex in a patient with DCM indicates ventricular dilation and HF. Report to the provider immediately. (An S4 suggests a stiff ventricle and diastolic dysfunction, more typical of HOCM or restrictive cardiomyopathy.)

• Peripartum cardiomyopathy is LV systolic dysfunction (LVEF nearly always below 45%) presenting toward the end of pregnancy or in the months after delivery, with no other cause found. The older “last month of pregnancy to 5 months postpartum” window has been dropped by the ESC Heart Failure Association. NCLEX can test this with a question about a postpartum woman presenting with dyspnea – the answer is peripartum cardiomyopathy.

• Cardiac amyloidosis classic triad: sparkling myocardium on echo + low voltage ECG + elevated BNP disproportionate to LV size. The combination of thickened walls (suggesting hypertrophy) with low-voltage ECG (when hypertrophy should cause high voltage) is a signature finding of amyloid deposition.

• Takotsubo is triggered by catecholamine surge – always ask about a recent emotional or physical stressor (death of a loved one, accident, severe illness, medical procedure). The patient is most commonly a post-menopausal woman. Coronary arteries are normal on angiogram.

• Limit catecholamines (epinephrine, dobutamine) in Takotsubo – the syndrome is catecholamine-mediated, inotropes can provoke LVOT obstruction, and patients given catecholamines have had high mortality. A patient in shock needs an echo to look for LVOT obstruction, and refractory shock is managed with mechanical circulatory support.

• HOCM and sudden cardiac death in athletes – HCM is one of the most common causes of SCD in young people; in a US registry of young competitive athletes it was the most common cardiovascular cause (36%). Exertional syncope or a family history of sudden death in a young relative needs urgent cardiology referral. Current guidelines no longer ban all patients with HCM from sport; decisions are individualized.

• ICD in DCM – indicated for primary prevention of SCD when EF remains ≤35% after at least three months of optimized GDMT. NCLEX may ask when ICD is appropriate – the EF ≤35% threshold is the key number.

• Kussmaul’s sign – JVP rises with inspiration instead of falling; found in restrictive cardiomyopathy and constrictive pericarditis. The right ventricle cannot accommodate increased venous return during inhalation due to its non-compliant or constrained surroundings.

• HCM is autosomal dominant – first-degree relatives of an HCM patient should be screened with echocardiography and genetic testing. NCLEX tests this as a teaching point for patient education after HCM diagnosis.

Internal links

• Heart failure nursing: assessment, interventions, and NCLEX review – DCM produces HFrEF and HOCM/restrictive produce HFpEF physiology; essential companion reference
• Atrial fibrillation nursing: assessment, interventions, and NCLEX review – AFib complicates all cardiomyopathy types; particularly dangerous in HOCM due to LV preload dependence
• Myocarditis nursing: assessment, interventions, and NCLEX review – viral myocarditis is a cause of DCM and shares early clinical features
• Pericarditis nursing: assessment, interventions, and NCLEX review – differential diagnosis for chest pain; constrictive pericarditis mimics restrictive cardiomyopathy
• Infective endocarditis nursing: assessment, interventions, and NCLEX review – cardiac structural disease cluster; shared SBE prophylaxis considerations
• MI/ACS nursing: assessment, interventions, and NCLEX review – ischemic cardiomyopathy is the most common cause of a dilated, failing LV; Takotsubo mimics STEMI at presentation
• Cardiovascular medications nursing reference – detailed pharmacotherapy reference for ACE inhibitors, beta-blockers, diuretics, antiarrhythmics
• Aortic dissection nursing: assessment, interventions, and NCLEX review – chest pain differential; hypertension management overlaps with cardiomyopathy management

References

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