Cardiomyopathy Nursing Guide

Cardiomyopathy Classification

Cardiomyopathies are diseases of the heart muscle that result in impaired cardiac function. They are classified by structural and functional phenotype:

Type	Ventricle	Systolic Function	Diastolic Function
Dilated (DCM)	Dilated, thin-walled	↓ Reduced LVEF	Normal or ↓
Hypertrophic (HCM)	Thickened (hypertrophied)	Normal or hyperdynamic	↓ Impaired (stiff ventricle)
Restrictive (RCM)	Normal size, rigid walls	Normal	↓↓ Severely impaired
Takotsubo	Apical ballooning	↓ Transient systolic failure	Usually recovers
Arrhythmogenic right ventricular (ARVC)	RV fibro-fatty replacement	↓ RV function	Variable

Dilated Cardiomyopathy (DCM)

Characterised by LV (or biventricular) dilation and systolic dysfunction (reduced ejection fraction). The most common cardiomyopathy worldwide.

Causes

Idiopathic (30–40%) — most common
Genetic/familial (25–30%) — TTN, LMNA, SCN5A mutations
Post-viral myocarditis (enterovirus, HIV, SARS-CoV-2)
Peripartum cardiomyopathy (GCC obstetric units)

Alcohol (less common in GCC Muslim population; seen in non-Muslim expats)
Ischaemic (post-MI remodelling)
Chemotherapy-related (anthracyclines, trastuzumab)
Tachycardia-induced (chronic uncontrolled AF)

Clinical Features

Heart failure symptoms: dyspnoea, orthopnoea, PND, reduced exercise tolerance
Signs: displaced apex, S3 gallop, functional mitral regurgitation murmur, raised JVP, peripheral oedema
Arrhythmias: AF, VT, VF (sudden cardiac death risk)
Thromboembolic risk (dilated stagnant LV → clot formation)

Management

Heart failure medications: ACE inhibitor/ARB/ARNI (sacubitril-valsartan), beta-blocker (bisoprolol, carvedilol), SGLT2 inhibitor, spironolactone
ICD (implantable cardioverter-defibrillator) if LVEF ≤35% on optimal medical therapy — prevents sudden death
CRT (cardiac resynchronisation therapy) if LVEF ≤35% + LBBB QRS ≥130ms — improves symptoms
Anticoagulation if AF or LV thrombus
Cardiac transplantation for end-stage

Peripartum Cardiomyopathy (PPCM)

PPCM: New-onset heart failure (LVEF <45%) in last month of pregnancy or within 5 months post-partum, with no other cause. More common in multiparous women, twin pregnancies, pre-eclampsia. Bromocriptine (prolactin inhibitor) + standard HF therapy. 50% recover LV function. GCC nurses in obstetric units must be aware.

Hypertrophic Cardiomyopathy (HCM)

Autosomal dominant genetic disorder causing asymmetric LV hypertrophy (most commonly septal), diastolic dysfunction, and risk of sudden cardiac death. Prevalence: 1 in 500. Most common inherited cardiac disorder.

Pathophysiology

Asymmetric septal hypertrophy → LV outflow tract obstruction (LVOTO) in 70% — obstructive HCM
Systolic anterior motion (SAM) of mitral valve → worsens LVOTO + mitral regurgitation
Diastolic dysfunction — stiff ventricle impairs filling
Myocardial disarray + fibrosis → arrhythmia substrate (VT/VF) → sudden cardiac death

Clinical Features

Exertional dyspnoea, chest pain, syncope (particularly on exertion)
Palpitations (AF, VT)
Sudden cardiac death (often first presentation in young athletes)
Murmur: ejection systolic murmur at left sternal edge — INCREASES on standing and Valsalva (reduces preload → worsens LVOTO); DECREASES on squatting (increases preload)

HCM murmur distinguisher: Louder on STANDING (preload ↓ → obstruction worse) and VALSALVA. Quieter on SQUATTING (preload ↑). Opposite pattern to most other murmurs. Aortic stenosis murmur decreases on standing.

Management

Lifestyle: avoid dehydration, extreme exertion, competitive sports (sudden death risk)
Beta-blockers (bisoprolol, metoprolol) — reduce LVOTO, control HR
Disopyramide or verapamil as alternative anti-obstructive agents
Mavacamten — new cardiac myosin inhibitor; reduces LVOTO
ICD for high-risk patients (SCD risk score ≥4%, prior cardiac arrest, sustained VT, family history of SCD, massive hypertrophy ≥30mm)
Septal reduction therapy (surgical myectomy or alcohol septal ablation) for drug-refractory LVOTO
AVOID: vasodilators (GTN, ACE inhibitors), diuretics in excess, digoxin — all worsen LVOTO

Restrictive Cardiomyopathy (RCM)

Normal or near-normal LV size and systolic function but severely impaired diastolic filling due to rigid, non-compliant ventricle. Mimics constrictive pericarditis.

Causes

Cardiac amyloidosis — most common (AL amyloid from plasma cell dyscrasia; ATTR amyloid hereditary/wild-type). GCC high-risk families (ATTR hereditary in certain populations)
Cardiac sarcoidosis
Haemochromatosis (iron deposits in myocardium)
Hypereosinophilic syndrome
Radiation-induced fibrosis

Features

Right heart failure predominates (JVP, ascites, peripheral oedema)
Kussmaul's sign (JVP rises on inspiration)
Low voltage ECG + thick walls on echo (amyloid)

Takotsubo Cardiomyopathy (Stress Cardiomyopathy)

Transient, reversible LV dysfunction characterised by apical ballooning and basal hypercontractility, triggered by emotional or physical stress. Also called "Broken Heart Syndrome."

Pattern: Apical ballooning + basal hypercontractility on echo. ECG: ST elevation/T wave inversion (mimics STEMI). Troponin mildly elevated. Coronary angiogram: NO obstructive CAD (distinguishes from STEMI). Named after "takotsubo" (Japanese octopus pot) shape of the LV.

GCC Context

Triggered by: bereavement, major stress event, acute illness (including ICU admission)
Mostly post-menopausal women (90%)
Management: supportive — ACE inhibitors, beta-blockers; most recover LV function within 4–8 weeks
Islamic bereavement practices and emotional stress from family illnesses or disasters — trigger events recognised in GCC populations

MCQ Practice — Cardiomyopathy

Q1. A 25-year-old competitive footballer collapses during a match. ECG shows LVH, SAM of the mitral valve on echo, and a family history of sudden cardiac death. What is the most likely diagnosis?

A) Dilated cardiomyopathy

B) Cardiac tamponade

C) Hypertrophic obstructive cardiomyopathy (HOCM)

D) Aortic stenosis

✅ C — Young athlete + LVH + SAM + family history of SCD = HOCM. The most common cause of sudden cardiac death in young athletes. Exertional syncope is a cardinal feature. ICD is indicated in high-risk patients.

Q2. A woman with HOCM asks about her murmur. She is told it gets louder when she stands up. Why?

A) Standing increases blood pressure and worsens outflow

B) Standing reduces venous return (preload) → less LV filling → worse outflow tract obstruction → louder murmur

C) Standing causes mitral valve regurgitation to increase

D) Standing activates the vagus nerve which worsens obstruction

✅ B — In HOCM, reducing preload (standing, dehydration, Valsalva) brings the hypertrophied septum and mitral leaflet closer → worsens LVOTO → louder murmur. Increasing preload (squatting) widens the outflow tract → quieter murmur. This distinguishes HOCM from other murmurs.

Q3. A 35-year-old woman develops heart failure 3 weeks after delivery of her first child. Echo shows LVEF 35% with no other cardiac history. What is the most likely diagnosis?

A) Viral myocarditis from postpartum infection

B) Pre-existing dilated cardiomyopathy unmasked by pregnancy

C) Peripartum cardiomyopathy (PPCM)

D) Hypertrophic cardiomyopathy causing diastolic heart failure

✅ C — PPCM: new-onset heart failure (LVEF <45%) in the last month of pregnancy or within 5 months post-partum with no other identifiable cause. 50% recover LV function. Bromocriptine (prolactin inhibitor) is added to standard HF therapy. GCC obstetric nurses must recognise this presentation.

Q4. A patient with Takotsubo cardiomyopathy has ST elevation on ECG and mildly elevated troponin. What distinguishes this from STEMI?

A) The troponin rise in Takotsubo is much higher than in STEMI

B) Takotsubo does not cause chest pain

C) Coronary angiogram shows no obstructive coronary artery disease; apical ballooning on ventriculography

D) ECG changes in Takotsubo resolve within 30 minutes

✅ C — Takotsubo is distinguished from STEMI by: normal coronary arteries on angiogram + apical ballooning pattern on left ventriculography. Troponin is usually mildly elevated (disproportionately low for the extent of wall motion abnormality). LV function recovers in weeks. Triggered by emotional/physical stress.

Cardiomyopathy — Nursing Guide

Cardiomyopathy Classification

Dilated Cardiomyopathy (DCM)

Causes

Clinical Features

Management

Peripartum Cardiomyopathy (PPCM)

Hypertrophic Cardiomyopathy (HCM)

Pathophysiology

Clinical Features

Management

Restrictive Cardiomyopathy (RCM)

Causes

Features

Takotsubo Cardiomyopathy (Stress Cardiomyopathy)

GCC Context

MCQ Practice — Cardiomyopathy

MCQ Practice — Cardiomyopathy