Heart Failure and Intrinsic Myocardial Disease

Heart Failure Inability of the heart to pump blood at a rate that is adequate for the body’s needs. High mortality - >50% in less than 5 years Contributing cause of death in 300,000 annually, 2,000,000 being treated Leading discharge diagnosis in hospitalized patients over 65 years of age

Starling’s Law of the Heart The stroke volume of the heart is a function of the diastolic fiber length and the heart will pump whatever volume of blood is brought to it. Or the increased preload dilation helps to sustain cardiac performance by enhancing contractility

Principles of cardiac Dysfunction Failure of the pump itself An obstruction to flow - overworks the chamber behind the obstruction Regurgitant flow - increased volume workload Disorders of cardiac conduction - non uniform and inefficient contractions Disruption of the continuity of the circulatory system

Congestive Heart Failure Cardiogenic - myocardial weakness High output - excessive workload Thyroid toxicosis Reduced return - inadequate filling (cardiac tamponade)

Heart Failure Systolic dysfunction- most, deterioration of myocardial contractile function Diastolic dysfunction- inability of the chamber to relax, expand or fill during diastole

Left Sided Heart Failure Ischemic heart disease Hypertension Aortic and mitral valve disease Non ischemic myocardial disease (cardiomyopathies)

Pulmonary edema- left heart failure

Pulmonary edema: left heart failure

Right - Sided Heart Failure Left heart failure Cor pulmonale - pure right heart failure due to pulmonary hypertension

Pitting edema- rt. Heart failure

Effects of Heart Failure Dilation of the heart (LHF & RHF) Pulmonary edema and congestion(LHF) Pleural effusions (LHF & RHF) Renal failure (pre-renal azotemia) LHF & RHF Congestion of liver - “nutmeg” liver (RHF) Splenic congestion(RHF) Ascites (RHF) Dependent edema (RHF)

Causes of CHF Congenital HD Ischemic HD Valvular HD Cardiomyopathy Inflammatory disease of the heart Nutritional, endocrine, metabolic

Cardiac Hypertrophy Onset of heart failure is preceded by cardiac hypertrophy Increase rate of protein synthesis, # of sarcomeres, # of mitochondria Pressure (concentric) hypertrophy At some point the heart can no longer accommodate the increased demand

Cardiac Hypertrophy Heart failure preceded by hypertrophy Pressure overloaded ventricles (HTN or AS) develop concentric hypertrophy- increased thickness and normal to reduced cavity diameter Volume overloaded ventricles (AR or MR), develop hypertrophy and dilatation IHD & pulmonary hypertension up to 600gm HTN, AS, MR or DCM up to 800 gm AR or HCM up to 1000 gm

Example of a hypertrophic heart from AS

Hypertrophy- normal dilated hypertrophic

Hypertrophy normal hypertrophy

Examples of box car nuclei

Myocardial Disease Clinical features Arrhythmias -EKG Pain Rapid cardiac enlargement Rapid onset of CHF Sudden Death By definition no significant coronary artery disease, valvular HD, or hypertensive HD

Myocarditis - Infectious Viral: coxsackie A, B, ECHO, influenza , polio, HIV interstitial lymphocytes isolated cell degeneration Rickettsial- more of a vasculitis Fungal and protozoan -toxoplasmosis and Chagas disease Bacterial Borrelia burgdorferi (Lyme disease) Corynebacterium diphtheriae- toxin

Lymphocytic myocarditis

Chaga’s disease toxoplasmosis

“Myocarditis”- Non-Infectious Hypersensitivity diseases Radiation Sarcoidosis, uremia

Cardiomyopathy Heart disease not due to: ischemia, hypertension, congenital abnormalities, or valvular heart disease Idiopathic(meaning not one of the above) Dilated cardiomyopathy (DCM) Hypertrophic cardiomyopathy (HCM) Restrictive cardiomyopathy

Primary Cardiomyopathy Dilated: cardiac dilation CHF, arrhythmias Hypertrophic: myocardial hypertrophy with or without outflow obstruction Restrictive: amyloidosis, endocardial fibroelastosis , endomyocardial fibrosis

Dilated Cardiomyopathy Progressive hypertrophy, dilation and contractile (systolic)dysfunction Residual from a myocarditis- some cases have shown viral nucleic acids in the myocytes Alcohol or other toxicity Pregnancy-associated Genetic - familial in some (20%) Most truly idiopathic

DCM Heavy >600gms (2 to 3 times normal) Large , flabby with dilated chambers Sometimes mural thrombi Coronaries clear Hypertrophied fibers, but stretched , large nuclei, and interstitial fibrosis

Clinical Features of DCM Any age but 20 to 50 most common Progressive congestive heart failure End stage have ejection fractions < 25% 50% die within 2 years, 25% 5 year survival rate Die of heart failure, arrhythmia, or embolism

Right endocardial biopsy technique

Dilated cardiomyopathy

Dilated cardiomyopathy

Dilated cardiomyopathy

Dilated CM

Dilated cardiomyopathy– note coronary arteries show no ASVD

Dilated cardiomyopathy

Hypertrophic Cardiomyopathy Myocardial hypertrophy Abnormal diastolic filling Intermittent left ventricular outflow obstruction Hypercontracting heart Large heart, asymmetric septal hypertrophy Myofiber disarray

HCM Over half are familial, auto. dominant Any one of 4 genes that encode proteins of the sarcomeres B-myosin heavy chain (most) Cardiac troponin T Alpha-tropomyosin Myosin-binding protein C

HCM Clinical Features Reduced chamber size and reduced stroke volume leads to massively hypertrophied left ventricle DOE Harsh systolic ejection murmur Focal ischemia, anginal pain Atrial fib, emboli, endocarditis & sudden death

Hypertrophic cardiomyopathy

Hypertrophic CM Note septal bulging

Hypertrophic cardiomyopathy

Secondary Cardiomyopathy Alcoholic Metabolic thyroid, K+ glycogen storage nutritional hemochromatosis

Iron stain- hemachromatosis

Restrictive CM Decrease in ventricular compliance resulting in impaired ventricular filling during diastole - contractile function OK Confused with constrictive pericarditis Idiopathic or radiation fibrosis, amyloid, sarcoidosis, metastatic tumor Heart normal size and usually not dilated

Restrictive cardiomyopathy –amyloid

2o Cardiomyopathy Connective tissue diseases: SLE, PSS, PAN Neuromuscular disease: MD, etc. Mucopolysaccharidoses: Hunter’s Toxic: emetine, arsenic, cobalt Infiltrative: leukemia Drugs- Anthracycline (doxorubicin and daunorubicin) dose dependent >500 mg/m2 lipid peroxidation of myocyte membranes

Leutic (Syphilis) Heart Disease Obliterative endarteritis - plasma cells Aneurysm of thoracic aorta Tree barking Narrowing of ostia of coronary arteries Severe ASVD at root of aorta Dilation of aorta valve ring - (aortic insufficency) Marked LVH - cor bovinum

Syphilitic aortitis and aortic insufficiency Weaken aorta with Aneurysm of ascending aorta Dilated aortic root

Carcinoid Heart Disease Serotonin, 5-hydroxtryptophane, bradykinin, and histamine Most on right side Plaque-like thickenings Fusion of tricuspid leaflets

Note thick cusps- stenosis Carcinoid valvular disease

Summary Mitral Stenosis : Rheumatic Heart Disease Mitral insufficiency: myxomatous degeneration (mitral valve prolapse), damaged papillary muscle due to infarct Aortic stenosis: calcification of normal and congenitally bicuspid aortic valves Aortic insufficiency: dilation of the ascending aorta, related to hypertension and aging