3. Overview
3
Definition
Cardiomyopathies are diseases of heart muscle.
cardiomyopathy is a myocardial disorder in which the heart
muscle is structurally and functionally abnormal in the
absence of coronary artery disease, hypertension, valvular
disease, and congenital heart disease sufficient to explain the
observed myocardial abnormality.
4. 4
Although some have defined cardiomyopathy to include myocardial
disease caused by known cardiovascular causes (such as
hypertension, ischemic heart disease, or valvular disease), current
major society definitions of cardiomyopathy exclude heart disease
secondary to such cardiovascular disorders.
5. 5
CLASSIFICATION
In 1980, the World Health Organization (WHO) defined
cardiomyopathies as "heart muscle diseases of unknown
cause" to distinguish cardiomyopathy from cardiac dysfunction
due to known cardiovascular entities such as hypertension,
ischemic heart disease, or valvular disease.
6. In clinical practice, however, the term "cardiomyopathy"
has also been applied to diseases of known
cardiovascular cause (eg, "ischemic cardiomyopathy"
and "hypertensive cardiomyopathy").
6
7. 1995 WHO/International Society and Federation of
Cardiology (ISFC) Task Force on the Definition and
Classification of the Cardiomyopathies expanded the
classification to include all diseases affecting heart muscle
and to take into consideration etiology as well as the
dominant pathophysiology .
7
8. They were classified according to anatomy and physiology into the
following types, each of which has multiple different causes:
Dilated cardiomyopathy (DCM)
Hypertrophic cardiomyopathy (HCM)
Restrictive cardiomyopathy (RCM)
Arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D)
Unclassified cardiomyopathies
8
10. Dilated cardiomyopathies (DCM)
DCM is characterized by dilation
and impaired contraction of one or
both ventricles.
The dilation often becomes severe
and is invariably accompanied by
an increase in total cardiac mass
(hypertrophy).
Affected patients have impaired
systolic function and clinical
presentation is usually with features
of HF. 10
11. Dilated cardiomyopathies (DCM)
The wall becomes thin and stretched, compromising cardiac
contractility poor left ventricular function(systolic dysfunction).
Usually all chambers are enlarged
Most common cardiomyopathy in Uganda
Genetic causes and acquired
Childhood /fourth and fifth decades of life.
11
12. 12
Epidemiology
One of the most common causes of heart failure and the
most common indication for heart transplantation worldwide.
The incidence of DCM has been estimated to be five to eight
cases per 100,000 population, with a prevalence of 36 per
100,000.
Evaluation with ECG and echocardiogram of 767 relatives of
189 probands with DCM revealed unrecognized disease in
4.6 percent of relatives.
13. 13
Epidemiology
Also, LV systolic dysfunction may be more prevalent than
previously estimated as suggested by a study finding that 14
percent of the middle-aged and older adult population have
asymptomatic left ventricular (LV) systolic dysfunction.
17. Clinical presentation
6/5/2023 17
Complications related to DCM
Arrhythmias (atrial fibrillation, supraventricular and
ventricular arrhythmias)
Thromboembolic events due to dilated cardiac
chambers and haemostasis.
Thorough family history and pedigree
Hx of DCM, or who have suffered from a
thromboembolic event or sudden cardiac death before
the age of 30 years.
18. Examination findings
Displaced apical beat
Murmur of mitral regurgitation
Features of systolic heart failure
Edema
Ascites
↑JVP
Clinical presentation
19. Echocardiography -2DE
Left ventricular end diastolic dimension (LVEDD) > 117% predicted value corrected for
age and body surface area.
Fractional shortening (FS) <25% and or
Ejection fraction (EF). <0.4
19
Investigations
22. Investigations …
Viral serology
Acute myocarditis.
Titres of neutralising antibodies (IgM Ab) four
times above normal, over a period of 2–4 week
HIV serology
24. Definition
A hypertrophied, nondilated left ventricle in the absence of
another cardiac, systemic, metabolic, or syndromic
disease.
Nonobstructive HCM: Hypertrophic cardiomyopathy without
obstruction of the left ventricular outflow tract (LVOT)
Hypertrophic obstructive cardiomyopathy (HOCM): HCM
with left ventricular outflow tract obstruction (LVOTO) that is
dynamic
HYPERTROPHIC CARDIOMYOPATHY (HCM)
24
25. Most often (60 to 70 percent) caused by mutations in one of
several sarcomere genes which encode components of the
contractile apparatus
Asymmetric left ventricular (LV) hypertrophy -wide array of
clinical manifestations and hemodynamic abnormalities
(with/without left ventricular outflow tract obstruction)
25
HYPERTROPHIC CARDIOMYOPATHY (HCM)
26. Second most common cardiomyopathy
Two types are distinguished:
Obstructive type/hypertrophic obstructive cardiomyopathy (HOC
M): ∼70% of cases
Nonobstructive type: ∼30% of cases
Alongside myocarditis, HCM is one of the most frequent
causes of sudden cardiac death in young patients,
especially young athletes.
26
Epidemiology
30. HCM is a genetic condition characterized by otherwise
unexplained left ventricular hypertrophy.
Most common hereditary heart disease
Autosomal dominant inheritance with varying penetrance
Most commonly caused by mutations of
the sarcomeric protein genes (e.g., myosin heavy
chain, myosin binding protein C) → disorganization
of myocyte architecture characterized by myofibrillar disarray
and fibrosis.
80% -mutation in either MYH7 or MYBPC3
30
Etiology
32. Large LV septum
→ LV outflow
tract is narrow
Anterior leaflet of
mitral valve is
now closer to LV
septum
During systole
anterior leaflet of
the mitral valve
may obstruct LV
outflow and
redirect it to
mitral regurge
June 5, 2023 32
Left ventricular outflow obstruction In
hypertrophic CM
33. HCM is characterized by hypertrophy of the left
ventricle ; most commonly occurs with asymmetrical septal
involvement, which leads to diastolic
dysfunction (impaired left ventricular relaxation and filling)
→ reduced systolic output volume → reduced peripheral
and myocardial perfusion. → cardiac arrhythmia and/or heart
failure and increased risk of sudden cardiac death.
33
Pathophysiology of Hypertrophic Cardiaomyopathy
34. Typical features include:
Increased LV wall thickness with septal predominance , no
dilation of left ventricle
Myofibrillar disarray, interstitial fibrosis, and myocyte
hypertrophy
Concentric hypertrophy: a form of cardiac
remodeling characterized by parallel duplication
of sarcomeres that leads to thickening of the ventricular wall.
34
Nonobstructive and obstructive HCM
35. In HOCM, concentric hypertrophy is caused by genetic mutations.
Concentric hypertrophy can also occur secondary to the following
diseases, then potentially mimicking HCM:
Hypertension and aortic valve stenosis (due to chronic pressure
and volumeoverload): Chronic hypertension → increased afterload → incre
ased myocardial wall tension → changes in myocardial gene expression
→ sarcomeres laid down in parallel → increased left ventricular thickness
→ decreased left ventricular size → diastolic dysfunction
Storage disorders (e.g., Fabry disease, amyloidosis) and hereditary
syndromes (e.g., Friedreich ataxia, Noonan syndrome)
35
Nonobstructive and obstructive HCM
36. Pathomechanism:
o LVOT obstruction → increased LV systolic pressure
→ prolongation of ventricular relaxation
→ increased LV diastolic pressure → exacerbation of
HCM with further reduction of cardiac output.
36
Hypertrophic obstructive cardiomyopathy
37. Symptoms:
Frequently asymptomatic (especially the nonobstructive
type)
Exertional dyspnea
Angina pectoris
Dizziness, lightheadedness, syncope
Palpitations, cardiac arrhythmias
Sudden cardiac death (particularly during or after intense physical
activity).
37
Clinical features
38. Physical examination
Systolic ejection murmur (crescendo-
decrescendo)
Increases with Valsalva maneuver
Decreases with:
Hand grip, squatting, or passive leg elevation
Drugs that decrease cardiac contractility (e.g., beta blockers)
38
Clinical features
39. Possible holosystolic murmur from mitral regurgitation
Sustained apex beat
S4 gallop
Paradoxical split of S2
Pulsus bisferiens: LV outflow obstruction causes a sudden
quick rise of the pulse followed by a slower longer rise
(biphasic pulse).
Physical examination
39
41. Echocardiography is the best initial and confirmatory test.
Other investigations (e.g., ECG, CXR, cardiac MRI, exercise
testing, and screening for coronary artery disease or genetic
diseases) can be done on a case-by-case basis.
41
Diagnostics
42. Both of following are required to make the
diagnosis:
Left ventricular nondilated hypertrophy (usually ≥
15 mm in adults)
Absence of other cardiac or systemic diseases that
could explain hypertrophy (e.g., long-
standing hypertension or aortic stenosis).
42
Diagnostic criteria
43. Findings in patients with HCM Wall thickness
Asymmetrically thickened left ventricular wall, (≥ 15
mm), typically involving the septum
LV wall thickness ≥ 30 mm is associated with a high risk
of sudden death.
43
Transthoracic echocardiography with Doppler
44. Outflow tract abnormalities
Systolic anterior motion of the mitral valve
Mitral regurgitation
↑ LVOT pressure gradient via Doppler echocardiography.
Other findings
Left atrial enlargement
Systolic function typically normal
Diastolic dysfunction
44
Transthoracic echocardiography with Doppler
45. Findings more specific to HOCM
Asymmetrically thickened interventricular septum
Dynamic LVOT obstruction due to contact
between the septum and mitral
valve during systole.
45
Transthoracic echocardiography with Doppler
47. Indication: all patients with suspected HCM
Classic findings: commonly seen in obstructive
HCM
ECG signs of LVH ( Sokolow-Lyon criteria )
Deep Q waves, particularly in the inferior (II, III, and
aVF) and lateral (I, aVL, V4–6) leads
Giant inverted T waves in the precordial leads.
47
ECG findings in HCM
48. Other supportive findings
Nonspecific ST segment and T-wave changes
P wave changes indicating left atrial
enlargement (e.g., P mitrale)
LBBB
Associated dysrhythmias: Ventricular
tachycardia, atrial fibrillation, or atrial flutter.
48
ECG findings in HCM
49. Indication: considered for patients presenting
with dyspnea or chest pain of unknown etiology
Suggestive findings
The heart can be normal or enlarged.
Left atrial enlargement is commonly seen in mitral regurgitation.
Possibly signs of pulmonary congestion (e.g., pulmonary
edema) in severe forms of CHF.
49
Chest x-ray
50. Provocation tests (e.g., exercise testing) are
obligatory if no obstruction is discernible at rest.
Exercise echocardiography
Findings: LVOT obstruction and/or mitral regurgitation.
50
Exercise testing
51. Treadmill exercise testing
Findings
Clinical observation for development of symptoms
(e.g., dyspnea, palpitations)
Blood pressure monitoring: hypotension
ECG tracings with arrhythmias and/or signs of ischemia.
51
Exercise testing
52. Advantages
Better visualization of segmental left ventricular
hypertrophy located in the anterolateral wall or apex compared
to echocardiography
Better detection of apical aneurysms compared
to echocardiography
Identification of myocardial fibrosis with late gadolinium
enhancement (LGE).
52
Cardiac MRI (cMRI)
53. Genetic testing and family screening: All patients should be assessed for
familial inheritance and receive genetic counseling. Indications for genetic
testing
Considered reasonable in index patients to identify first-degree family members who may
be at risk of HCM
Index patients with an atypical presentation or for whom another genetic causeis
suspected
First-degree relatives: Screen by clinical assessment (with or without genetic
testing).
Patients who undergo genetic testing should receive genetic counseling from
someone who is knowledgeable about genetic cardiovascular diseases.
53
Additional studies
54. General approach
All patients
Lifestyle changes
Avoidance of dehydration
Maintaining a healthy body weight
Avoidance of excessive alcohol intake
Avoidance of strenuous exercise and situations that will likely
cause vasodilation (e.g., environmental factors such as high
temperatures)
54
Treatment
55. An AICD is considered for primary or secondary prevention of sudden
cardiac death (SCD) in patients who are at high risk.
Absolute indication: known prior history of ventricular
fibrillation, sustained ventricular tachycardia, or cardiac arrest
Relative indications
Syncope of unknown cause
Family history of SCD in a first-degree relative
LV wall thickness ≥ 30 mm
55
Automated implantable cardioverter
defibrillator (AICD)
56. Initial therapy: for all symptomatic patients with
obstructive or nonobstructive HCM
First-line: Beta blockers (e.g., propranolol 40–80 mg
PO every 8–12 hours OR atenolol 25–150 mg PO once
daily OR nadolol 40–80 mg PO once or twice daily )
Titrate to goal resting heart rate < 60–65/minute
56
Recommended pharmacotherapy
57. Second-line: Nondihydropyridine CCBs
Consider in patients who do not tolerate or respond to beta
blockers
Verapamil (40 mg PO every 8 hours; titrated up to 480 mg/day) is
preferred, but should be avoided if there
is hypotension or dyspnea at rest.
Diltiazem (60 mg PO every 8 hours; titrated up to 360 mg/day) may
be considered in patients with an intolerance or
contraindications to verapamil.
57
Recommended pharmacotherapy
58. Additional therapy: to consider adding to beta-
blocker or CCB if symptoms are persistent Obstructive
HCM: Disopyramide (controlled release 200–250 mg
PO twice daily; titrated up to 400–600 mg/day)
Obstructive HCM, or nonobstructive HCM with LVEF > 50%):
Oral diuretics, e.g., furosemide ( 20–40 mg PO once daily;
titrate as needed to a single dose once or twice daily)
58
Recommended pharmacotherapy
59. Medications to be avoided in LVOT obstruction
High-dose diuretics
Digoxin
Spironolactone
ACE inhibitors and ARBs
Dihydropyridine CCBs (e.g., nifedipine)
Vasodilators (e.g., nitrates and PDE-5 inhibitors)
Positive inotropes (e.g., dopamine, dobutamine, norepinephrine)
Medication to be avoided in nonobstructive HCM
Digoxin (except in atrial fibrillation with an LVEF ≤ 50%)
59
Pharmacotherapy to avoid
60. Septal reduction therapy
Dual-chamber pacemaker: Consider for patients who are
poor candidates for septal reduction therapy.
Heart transplant: Consider in end-stage nonobstructive HCM
when LVEF ≤ 50%.
60
Invasive therapy
61. Hypotension:
Management typically involves fluids and vasopressors with
purely vasoconstricting effects and no inotropic effects,
e.g., phenylephrine.
In patients with severe LVOTO who have cardiogenic
shock with pulmonary edema, vasoconstrictors may need to be
combined with beta-blockers, e.g., esmolol.
61
Complications
62. Heart failure
May require medications, e.g., ACEIs, that are typically avoided in uncomplicatedHOCM
May require discontinuation of negative inotropic medication, e.g., nondihydropyridine
CCBs
Atrial fibrillation Typically requires anticoagulation and either rate control orrhythm
control
May also require medications, e.g., digoxin, that are typically avoided in uncomplicated
HCM
Ventricular dysrhythmias
AICD placement
Some patients may benefit from antiarrythmic medication and radiofrequency ablation of
arrhythmogenic foci.
62
Complications
63. RESTRICTIVE CARDIOMYOPATHY
Restrictive cardiomyopathy (RCM) is a
rare type of cardiomyopathy characterized
by marked diastolic dysfunction, normal
(or near-normal) systolic function, and
normal ventricular volumes.
RCM occurs as a result
of myocardium distortion due
to proliferation of abnormal tissue or the
deposition of abnormal compounds.
64. RESTRICTIVE CARDIOMYOPATHY
Ventricular wall stiffness
Diastolic dysfunction of non dilated ventricle,
with mildy reduced contractility (EF > 30-50% )
Right and left atria enlargement
Elevated end diastolic pressure
64
65. Rare , 5% of all cases of cardiomyopathy (Brown K et
al,2022)
Prevalence varies depending on regionality , ethnicity, age,
and gender.
65
Epidemiology
66. Infiltrative cardiomyopathy
Amyloidosis: caused by an accumulation of
abnormal proteins in the myocardium
Sarcoidosis: secondary to deposition of granulomas in
the myocardium.
Storage disorders
Hereditary hemochromatosis; more commonly
causes dilated cardiomyopathy
66
Etiology
67. Endomyocardial disorders
Hypereosinophilia (Löffler endocarditis): eosinophilic
infiltration of the myocardium
Endocardial fibroelastosis: a diffuse thickening of the left
ventricle endocardium from the proliferation of fibrous and
elastic tissue
Most commonly occurs in the first two years of life
Iatrogenic
Radiotherapy to the chest
67
Etiology
68. Pathophysiology of Restrictive Cardiomyopathy
Due to infiltration of abnormal substances between myocytes, storage of abnormal
metabolic products within myocytes, or fibrotic injury
68
71. ECG
Low -to-normal voltage in the QRS complex despite thickened cardiac muscle in the absence
of valvular or hypertensive disease may lead one to suspect amyloidosis
Sinus tachycardia, atrial fibrillation, sinus bradycardia if SA node infiltrated
Complex ventricular arrhythmias : are poor prognostic sign
Q waves : pseudo infarct from fibrosis
BBB, AVB
71
Investigations
72. ECHO- RCM VS Constrictive pericarditis
Normal left ventricular ejection fraction
Elevated left ventricular filling pressure
Strain imaging can show impaired longitudinal contraction despite
the normal ejection fraction
dilated atria and myocardial hypertrophy.
In amyloidosis an unusually bright echo pattern from the myocardium
may be observed
72
Investigations …
73. CARDIAC MRI-gadolinium enhancement pattern is highly
suggestive of amyloid (RCM VS constrictive pericarditis)-
pericardial thickening
Endomyocardial biopsy-gold standard for the diagnosis of
cardiac amyloidosis. Fat pad aspiration is positive in about
50% of cases.
73
Investigations …
77. Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC) is
a genetically determined heart muscle disorder
characterized histologically by loss of cardiomyocytes with
replacement by fibrous or fibrofatty tissue in the right
ventricular myocardium; clinically by ventricular
arrhythmias, heart failure, and sudden death; and
histologically by cardiomyocyte loss and replacement.
77
Arrhythmogenic Right Ventricular Cardiomyopathy
78. The disease is seen in patients of European,
African, and Asian descent, with an estimated
prevalence between 1 in 1000 and 1 in 5000
adults.
78
Epidemiology
79. The natural history of ARVC is divided into phases:
Early phase:- patients are usually asymptomatic, but
resuscitated cardiac arrest and sudden death may be the
initial manifestations, particularly in adolescents and young
adults.
Arrhythmic phase:- usually begins in adolescents and young
adults, patients note palpitations or syncope.
79
Clinical Manifestations
80. Symptomatic sustained arrhythmias: are usually
accompanied by ECG, morphologic, and functional
abnormalities of the right ventricle sufficient to fulfill
diagnostic criteria for ARVC.
Advanced phase : A small proportion of patients progress
to a more advanced phase, which is characterized by
diffuse right or left ventricular impairment that requires
conventional treatment for heart failure.
80
Clinical Manifestations
81. Clinical evaluation includes inquiry for symptoms of
arrhythmia
o syncope
o Presyncope
o sustained palpitation
A family history of premature cardiac symptoms or sudden
death.
81
Diagnosis
