Disease of The Myocardium
Professor mohammed Ahmed
Bamashmos
Professor of internal medicine Sanaa
university

Myocarditis
Definition
• Inflammatory process involving the myocardium ranging from acute to
chronic.
- An important cause of dilated cardiomyopathy .
Etiology
• Idiopathic
• Infectious
- viral (most common): coxsackie B, echovirus, poliovirus, HIV, mumps
- bacterial: S. aureus, C. perfringens, C. diphtheriae, Mycoplasma,
Rickettsia
- fungi
- spirochetal (Lyme disease - Borrelia burgdorferi)
- Chagas disease (Trypanosoma cruzi), toxoplasmosis
• Toxic: catecholamines, chemotherapy, cocaine
• Hypersensitivity/eosinophilic: drugs (antibiotics, diuretics, lithium,
clozapine), insect/snake bites
• Systemic diseases: collagen vascular diseases (SLE, RA, others), sarcoidosis,
autoimmune
• Other: giant cell myocarditis, acute rheumatic fever

Signs and Symptoms
• constitutional symptoms
• acute CHF
• chest pain - due to pericarditis or cardiac ischemia
• arrhythmias
• systemic or pulmonary emboli
• sudden death
Investigations
• ECG: non-specific ST-T changes ± conduction defects
• Bloodwork
- increased CK, troponin, LDH, and AST with acute myocardial necrosis ±
increased WBC,ESR, ANA, rheumatoid factor
- blood culture, viral titres
• CXR: enlarged cardiac silhouette
• Echo: dilated, hypokinetic chambers, segmental wall motion abnormalities
• Myocardial biopsy

• Management :
– Supportive care
– Restrict physical activity
– Treat CHF
– Treat arrhythmias
– Anticoagulation
– Treat underlying cause if possible
• Prognosis:
– Usually self- limited and often unrecognized
– Most recover
– May be fulminant death in 24-48 hrs
– Sudden death in young adults
– May progress to dilated cardimyopathy
– Few may have recurrent or chronic myocarditis

Dilated Cardiomyopathy (DCM)
Definition
• Unexplained dilation and impaired systolic function of one or both ventricles.
Etiology
• Idiopathic (presumed viral or idiopathic) - 50% ofDCM
• Alcohol
• Familial/genetic
• Uncontrolled tachycardia (e.g. persistent rapid AF)
• Collagen vascular disease: SLE, polyarteritis nodosa, dermatomyositis, progressive
systemic sclerosis
• Infectious: viral (coxsackie B, HIV), Chagas disease, Lyme disease, Rickettsial diseases,
acute rheumatic fever, toxoplasmosis
• Neuromuscular disease: Duchenne muscular dystrophy, myotonic dystrophy
• Metabolic: uremia, nutritional deficiency (thiamine, selenium)
• Endocrine: hyper/hypothyroidism, DM, pheochromocytoma
• Peripartum
• Toxic: cocaine, heroin
• Drugs: chemotherapies (doxorubicin, cyclophosphamide), anti-retrovirals,
chloroquine,clozapine, TCA
• Radiation

Pathophysiology :
– Impaired contractile function of the myocardium
🡪 progressive cardiac dilatation and eventually,
decrease ejection fraction
Clinical manifestations:
• CHF
• Systemic or pul. Emboli
• Arrhythmias
• Sudden death(major cause of mortality due to fatal
arrhythmia)

Investigations
• Bloodwork: CBC, electrolytes, Cr, bicarbonate, BNP, CK,
troponin, LFTs, TSH, TIBC
• ECG: variable ST -T wave abnormalities, poor R wave
progression, conduction defects(e.g. BBB),
arrhythmias
• CXR: global cardiomegaly (globular heart), signs of CHF,
pleural effusion
• Echo: chamber enlargement, global hypokinesis,
depressed LVEF, MR and TR, mural thrombi
• Endomyocardial biopsy: not routine, used to rule out a
treatable cause
• Angiography: in selected patients to exclude ischemic
heart disease

• Management :
– Treat underlying disease
– Treat CHF
– Anticoagulation to prevent thromboembolism
– Treat symptomatic or serious arrythmias
– Immunize against influenza and pneumococcus
– Surgical therapy –
• Cardiac transplant
• Vol. reduction surgery
• cardiomyoplasty

Hypertrophic Cardiomyopathy (HCM)
• Also known as hypertrophic obstructive
cardiomyopathy and idiopathic hypertrophic
subaortic stenosis .
• Issues are obstuction;arrythmia;diastolic
dysfunction
Pathophysiology
– Symmetrical or asymmetrical hypertrophy of the
myocardium either:
– Non obstructive
• Symptoms secondary to decreased compliance and
impaired diastolic filling
– Obstructive (latent or resting)
• Symptoms secondary to dynamic ventricular outflow
obstruction dimnishing cardiac output

• Clinical manifestation :
– Asymptomatic
– Dyspnea
– Cardiac ischemia
– Presyncope, syncope
– CHF
– Arrhythmias
– Sudden death
• Hallmark signs :
– Pulses
• Rapid upstroke pulse
• Bifid or bisferiens pulse
– Precordial palpation
• Localized , sustained , double / triple impulse apex beat
– Percordial auscultaion
• Normal or paradoxical S2
• S4
• Harse, systolic, diamond shaped murmur at apex

• Factors that influence obstruction
– These include any factors that
• Increase ventricular contractility
• Decrease preload
• Decrease afterload
• Investigation :
– ECG –
• LVH
– Echocardigraphy
• LVH
• Diastolic dysfunction
• Resting or dynamic ventricular outflow tract obstruction

Treatment :
• Supportive care
• Avoid factors which increase obstructions
• Avoid strenous exercise
• Treat arrhythmias
• Infective endocarditis prophylaxis
• Obstruction
– Beta blockers, verapamil or diltiazem
• Consider surgical options
• Dual chamber pacing to decrease obstruction
• Arrhythmias 🡪 amiodarone
Natural history :
– Variable ; some improve and stabilize over time while
others suffer from the complications
– AF; Infective endocarditis, sudden death

Restrictive Cardiomyopathy (RCM)
Definition
• Impaired ventricular filling with preserved systolic function
in a non-dilated, non-hypertrophied ventricle secondary to
factors that decrease myocardial compliance (fibrosis
and/or infiltration)
Etiology
• Infiltrative: amyloidosis, sarcoidosis
• Non-infiltrative: scleroderma, idiopathic myocardial fibrosis
• Storage diseases: hemochromatosis, Gaucher's disease,
glycogen storage diseases
• Endomyocardial
- endomyocardial fibrosis, Loeffler's endocarditis or
eosinophilic endomyocardial disease
- radiation heart disease
- carcinoid syndrome (may have associated tricuspid valve
or pulmonary valve dysfunction)

• Pathophysiology :
– Infiltration of the myocardium 🡪 decreased
ventricular compliance 🡪 diastolic dysfunction
• Clinical manifestation:
– CHF – diastolic dysfunction predominates
– Arrhythmias
– Systemic and pulmonary embolism

Investigations
• ECG: low voltage, non-specific, diffuse ST-T wave changes ± non-
ischemic Q waves
• CXR: mild cardiac enlargement
• Echo: LAE, RAE; specific Doppler findings with no significant
respiratory variation
• Cardiac catheterization: increased end -diastolic ventricular
pressures
• Endomyocardial biopsy: to determine etiology (especially for
infiltrative RCM)
Management
• exclude constrictive pericarditis
• treat underlying disease: control HR, anticoagulate if AF
• supportive care and treatment for CHF, arrhythmias
• heart transplant: might be considered for CHF refractory to
medical therapy
Prognosis
• depends on etiology

Disease of the Pericardium

Acute Pericarditis
• Most common pathologic process involving the pericardium
• Pericardial inflammation
Etiology of Pericarditis :
• idiopathic is most common: usually presumed to be viral
• infectious
- viral: Coxsackie virus A, B (most common), echovirus
- bacterial: S. pneumoniae, S. aureus
- TB
• fungal: histoplasmosis, blastomycosis
• post -MI: acute (direct extension of myocardial inflammation, 1-7 d
post -MI), Dressler's syndrome (autoimmune reaction, 2-8 wks post-
MI)
• post-cardiac surgery (e.g. CABG), other trauma
• metabolic: uremia (common), hypothyroidism
• neoplasm: Hodgkin's, breast, lung, renal cell carcinoma, melanoma
• collagen vascular disease: SLE, polyarteritis, RA, scleroderma
• vascular: dissecting aneurysm
• other: drugs (e.g. hydralazine), radiation, infiltrative disease (sarcoid

Presentation :
– Diagnostic traid –
• Chest pain
• Friction rub
• ECG changes
– Chest pain – alleviated by sitting up and leaning forward,
pleuritic, worse with deep breathing and supine position
– Percardical friction rub – may be uni , bi or triphasic
– Fever +/-
• Investigation :
– ECG – initially elevated ST in ant., lateral, and inferior leads
• Depressed PR segment
• ST segment is concave upwards
• 🡪 2-5 days later ST isoelectric with T wave flattening and
inversion
– Chest xray – normal size , pulmonary infiltrates
– Echo – pericardial effusion

• Treatment :
– Treat the underlying disease
– Anti inflammatory agent ; analgesics
• Complication :
– Recurrences, atrial arrhythmias, pericardial
effusions, tamponade, residual contrictive
pericarditis

Pericardial Effusion
Etiology
• Transudative (serous)
- CHF, hypoalbuminemia/hypoproteinemia, hypothyroidism
• exudative (serosanguinous or bloody)
- causes similar to the causes of acute pericarditis
- may develop acute effusion secondary to hemopericardium (trauma,
post-MI myocardial rupture, aortic dissection)
• physiologic consequences depend on type and volume of effusion, rate of
effusion development, and underlying cardiac disease
Signs and Symptoms
• may be asymptomatic or similar to acute pericarditis
• dyspnea, cough
• JVP increased
• arterial pulse normal to decreased volume, decreased pulse pressure
• auscultation: distant heart sounds ± rub
• Ewart's sign -Bronchial breathing and dullness to percussion at the
lower angle of the left scapula in pericardial effusion due to effusion
compressing left lower lobe of lung.

Investigations
• ECG: low voltage, flat T waves
• CXR: cardiomegaly, rounded cardiac contour
• Echo (procedure of choice): fluid in pericardial sac
• Pericardiocentesis: definitive method of determining
transudate vs. exudate, identify infectious agents,
neoplastic involvement
Treatment
• mild: frequent observation with serial echos, treat
underlying cause, anti-inflammatory agents
• severe: treat as in tamponade

Water bottle sign – cardiac silhouette

Cardiac Tamponade
• Major complication of pericardial effusion
• Accumulation of fluid in the pericardium in a quantity
sufficient to cause serious obstruction to the inflow of
blood to the ventricles results in cardiac tamponade
• Pathophysiology and symptomatology
– High intra pericardial pressure🡪 decreased venous return🡪
decreased diastolic ventricular filling🡪 decreased CO🡪
hypotension + venous congestion
• Symptoms :tachypnoea , dyspnoea , shock
• Sign – JVP raised , hepatic congestion

Clinical pearl :
– Classic quartet – hypotension , increased JVP, tachycardia,
pulsus paradoxus(inspiratory fall in systolic BP > 10 mmHg
during quiet breathing)
– Beck’s triad – hypotension, increased JVP, muffled heart
sounds
Investigations:
• ECG: electrical alternans (pathognomonic variation in
R wave amplitude), low voltage
• Echo: pericardial effusion, compression of cardiac
chambers (RA and RV) in diastole
• Cardiac catheterization

• Management :
– Urgent Pericardiocentesis – under ECHO,
FLUOROSCOPIC
– PERICARDIOTOMY
– Avoid diuretics and vasodilators( these decreased
venous return to already under filled RV 🡪
decrease LV preload 🡪 decrease in CO )
– Fluid administration may temporarily increase CO
– Treat underlying cause

Constrictive Pericarditis
Etiology
- Progressive thickening , fibrosis and calcification of
pericardium.
• chronic pericarditis resulting in fibrosed, thickened,
adherent, and/or calcified pericardium
• any cause of acute pericarditis may result in chronic
pericarditis
• major causes are idiopathic, post-infectious (viral,
TB), radiation, post-cardiac surgery, uremia, MI
- Tubercular pericarditis is a common cause

Symptoms & sign:
– Dyspnoea , fatigue, palpitations
– Abdominal pain
– Mimics CHF ( ascites, hepatosplenomegaly,
edema) (especially right-sided HF)
– Increased JVP, kussmaul’s sign(paradoxical
increase in JVP with inspiration).
– Pericardial knock (early diastolic sound)
– BP usually normal (and usually no pulsus
paradoxus)

Investigations
• ECG: non-specific
• CXR: pericardial calcification, effusions
• Echo/CT/MRI: pericardial thickening
• Cardiac catheterization: equalization of end-diastolic
chamber pressures (diagnostic)
Treatment
• Medical: diuretics, salt restriction
• Surgical: pericardiectomy (only if refractory to medical
therapy)
• Prognosis best with idiopathic or infectious cause and worst
in post-radiation. Death may result from heart failure