CARDIOMYOPATHYWhat, How, Why, e.t.c ……………

CLASSIFICATION

• Cardiomyopathy-

• Idiopathic

• Secondary

• Cardiomyopathy-

• Hypertrophic

• Dilated

• Restrictive

• Arrhythmogenic RV dysplasia

HYPERTROPHIC (HCM)

• ↑ myocardial thickness

• True myocyte hypertrophy

• Absence of loading conditions accounting for degree of hypertrophy (HTN, AS, AR)

• Genetics

• Familial, Auto dominant, Incomplete penetrance

• Variable phenotype and prognosis

• Cardiac sarcomere mutation (60%)

HCM PATHOLOGY

• Gross-

• Hypertrophy – LV/Both

• LV – Ant septum, Post septum, Free wall

• RV – Symmetric

• Histo-

• Disorg muscle bundles – whorled pattern

• Cell-cell orientation lost, Foci of disarray

• Cells – Broad, short, bizzare shape, myofibrillar archit lost

• Interstitial fibrosis

• Result-

• Systolic + Diastolic dysfunction

• Electrical instability

HCM PATHOPHYSIOLOGY

• Diast-

• LV compliance ↓, Filling abnormal, LVEDP

• Atrial press ↑

• Restrictive component +

• Syst-

• EF ↑

• LVOT obstruction – dynamic/static

• Ischaemic-

• ↓ Coronary flow reserve

• ↑ demand, supply N/↓

HCM DIAGNOSIS

• Unexplained/Disproportionate hypertrophy

• Screening of relatives

• History-

• Autopsy – SCD

• Any age

• Paroxysmal symptoms

• Exertional - dyspnoea, angina (typical/atypical), syncope

• Exam-

• JVP prominent a (RVH)

• Forceful apex, palpable atrial beat

• Pulse – rapid upstroke, low vol

• Ausc – Loud S4, ESM AA, PSM apex

HCM DIAGNOSIS 2

• CXR-

• LV enlargement

• LA RA enlargement

• PAH

• ECG-

• LVH, ST↓, T↓, deep S V1-V3

• P tall, M pattern

• AF, IVCD

• NSVT, VT, SVT

• ECHO-

• LVH, LV cavity↓, Diast dysfunc, LVOT gradient

• LA cavity↑

• MR, SAM

HCM DIAGNOSIS 3

• MRI- Myocardial fibrosis

• Cath-

• Chamber pressures

• Transvalvular & outlet gradients

• Systolic narrowing of coronary artery

HCM MANAGEMENT

• Asymptomatic-

• Genetic testing

• Screen relatives

• Annual follow-up

• Pharmacologic-

• β blocker, CCB, Verapamil, Amiodarone

• Anticoagulants

• IE suspicion high

• Surgical-

• Myotomy, myomectomy

• Papillary muscle remodelling

• MV repair/replacement

HCM MANAGEMENT 2• Alcohol septal ablation-

• Septal artery

• Elderly, failed medical

• Pacing-• AICD, RV pacing, CRT (AV sequential)

• Electrical cardioversion

• Stratify risk of SCD-• Family history of sudden death (≥2 premature (<40 years) sudden

deaths)

• Unexplained syncope within previous year

• Abnormal exercise blood pressure

• Nonsustained ventricular tachycardia (≥3 beats at ≥120 beats/min)

• Severe left ventricular hypertrophy (>3 cm)

• Severe left ventricular outflow tract obstruction (>90 mmHg)

• Cardiac arrest (or sustained ventricular tachycardia)

DILATED (DCM)• Chamber dilatation & Systolic dysfunction (LV, LV+RV)

• Absence of CAD, valve disease, pericardial disease

• Causes-

• Genetic-

• Autosomal dominant, incomplete penetrance

• X-linked – Duchenne, Becker’s, Emery Driefuss

• Acquired-

• Infectious myocarditis

• ChemoRx, RadioRx

• Alcohol, cocaine

• Nutritional deficiency – thiamine, calcium

• Iron overload

• Inflammatory, autoimmune disorders

• Endocrinopathy – hypothyroidism, DM

• Pregnancy, tachycardia

DCM PATHOLOGY

• Gross-

• Dilated chambers – Vent mass↑, Vent thickness N/↓

• Mural thrombi, platelet aggregates

• Histo-

• Patchy fibrosis

• T-lymphocyte & macrophage infiltration

• Myocyte death

• Myofibrillary loss

• Result-

• Slowly progressive dilatation

• Progressive LV systolic dysfunction

• Conduction defects - late

DCM DIAGNOSIS

• History-

• Progressive cardiac failure

• Insidious fatigue, dyspnoea, ↓exercise tolerance

• Arrhythmia – AF, VT, AV block

• Systemic embolism

• Incidental ECG, CXR, ECHO findings

• Exam-

• Normal

• CCF – Hepatomeg, ascites, pedal edema , JVP↑

• Cardiomegaly, apex - lateral, diffuse & dyskinetic

• Low pulse vol & press, Pulsus alternans, Low SBP

• Ausc – S2 spilt/paradox, loud P2, S4, S3, MR, TR

DCM DIAGNOSIS 2

• ECG – Sinus tachy, nonspecific ST (fibrosis), arrhythmia, conduction defects

• CXR – Cardiomeg, ↑pulm markings, pleural effusion

• ECHO –

• LV dilatation, syst & diast dysfunc, intracavit thrombus

• Func MR TR

• Pulm art press↑

• Cardiac biomarkers - ↑ CKMB, Trop I&T, ANP

• MRI – Dimensions, fibrosis

• Exercise testing – Func class, progress, pre-Tx

• Cath – Pre-Tx

DCM MANAGEMENT• Aims-

• Improve symptoms

• Attenuate disease progress

• Prevent complications (arrhythmia, stroke, sudden death)

• Pharmac-

• Diuretics

• ACEi, ARB, β blockers

• Digoxin, anticoagulants

• Antiarrhythmics – Caution (neg intotropic, proarrhythmic)

• Non-pharmac-

• PPI – AICD, CRT

• MVR

• Dor & Batista Sx

• LV assist device, artificial heart

• Cardiac Tx

RESTRICTIVE (RCM)

• ↑ stiffness of myocardium

• Vent press ↑↑ for small vol ↑

• Diast/syst volumes = N/↓

• N vent thickness

• Causes-

• Infiltrative – amyloidosis, sarcoidosis

• Storage – haemochromatosis, Fabry’s, glycogen storage

• Fibrotic – radiation, scleroderma, drugs (doxorubicin)

• Metabolic – carnitine def, fatty acid metab disorders

• Endomyocardial – endomyocardial fibrosis, hypereosinophilic syn

• Misc – carcinoid syndrome

RCM PATHOLOGY• Heterogenous aetiology

• Gross-

• Biatrial dilatation

• No LVH, N heart wt

• Small vent cavity

• Histo-

• Idiopathic-

• Nonspecific, patchy interstitial fibrosis, myocyte disarray

• Endomyocardial fibrosis-

• Necrotic – eosinophilic abscess, necrotic arteritis, mural thrombus

• Thrombotic – endocardial + intracavitary thrombus

• Fibrotic – dense fibrosis, fill cavity, impaired valve function

• Pathophysiology-

• Impaired relaxation, ↓ volume, sudden mid-diastolic pressure ↑

RCM DIAGNOSIS

• Insidious symptoms

• Lt side - pulmonary congestion, MR

• Rt side – JVP ↑, hepatomegaly, ascites, TR

• CXR – cardiomegaly, pulmonary infiltrates

• ECG – non-specific repolarisation defects, conduction defects

• ECHO-

• Enlarged atria

• N ventricular size, intracavitary thrombus

• Fibrosis ventricular myocardium

• MR, TR

• Cath – sudden mid-diastolic vent press ↑

RCM MANAGEMENT

• No effective Rx for advanced cases

• Symptomatic Rx

• Diuretics for HF

• Antiarrhythmics – sustained/symptomatic arrhythmias

• Digoxin

• Anticoagulants – warfarin

• Antiplatelets

• Poor prognosis

• Surgery-

• MVR/TVR

• Decortication +/-

• Selected patients

OTHERS

Arrhythmogenic RV dysplasia

• RV myocardium

• Later LV and RV involved

• 50% inherited, AD

• RV wall thinning, aneurysm

• Myocardium – fibrofatty, fibrosis, lymphocytic infiltration

• Palpitation, syncope, chest pain, DoE

• Ventricular arrhythmia, HF, SCD

• ECG - T↓, wide QRS, IVCD, Vent arrhythmias

• ECHO – RV (dilatation, hypo/dyskinesia, thinning, aneurysm, scarring), LV dilatation

• Cardiac MRI, endomyocardial Bx

ARVD (contd)

• Rx according to –

• Symptoms

• Arrhythmias

• Risk of SCD

• β-blockers, diuretics, ACEi

• Anticoag, amiodarone

• AICD

• Cardiac Tx

LV NON-COMPACTION

• Non-compaction of trabecular/spongiform layer

• Assoc ASD, VSD, CoA

• Echo – diagnostic

• HF, systemic emboli, arrhythmia.

TAKOTSUBO

• Stress cardiomyopathy

• Apical LV dysfunction

• Mimics MI

• Chest pain, ST↑, biomarkers↑

• Emotional/physical stress

• Conservative Rx

• Spontaneous recovery