Heart Failure

Cardiac output insufficient for metabolic requirements of the body

Types:

Systolic dysfunction – decreased myocardial contractility

Diastolic dysfunction – insufficient expansion for ventricular volume

Problems accentuated by increased demand – high output heart failure

Forward failure: hypoperfusion

Backward failure:

congestion, eg hepatic congestion, pulmonary edema;

Raised ventricular end diastolic pressure(VEDP), increased venous pressure in RVF

CHF – Body’s Compensation

Tachycardia

Frank-Starling mechanism

increased End Diastolic Volume increases force of contraction

Compensated vs decompensated heart failure

Myocardial hypertrophy

Concentric hypertrophy in pressure overload, eg HTN, AS

Eccentric hypertrophy in volume overload eg AR, MR; heart will increase in size also

induction of fetal genes in the process makes the heart even more ineffective

Oxygen demand of the heart will be increased, making the matters worse.

Renin-angiotensin-aldosterone system

Secondary hyperaldosteronism causes a vicious cycle

Catecholamines – positive inotropic effect

Adrenergic redistribution of blood flow

Increase oxygen extraction from hemoglobin

Left-sided Heart Failure

Ischemic heart disease

Hypertension

Aortic and mitral valve disease

Myocardial disease, eg myocarditis and cardiomyopathy

Major causes of valvular diseases

Rheumatic heart disease

Infective endocarditis: acute valvular insufficiency( regurgitation)

Senile calcific aortic stenosis

Mitral valve prolpase syndrome

Dilated cardiomyopathy

MI causing papillary muscle dysfunction or rupture

Marfan syndrome causing aortic regurgitation

Rheumatoid arthritis

Syphilitic aortitis

Dissection of aorta( proximal or type A)

Lungs – Pulmonary edema

c/f (clinical features)

Dyspnea – breathlessness

Orthopnea – dyspnea lying down

Paroxysmal nocturnal dyspnea – extreme dyspnea

S3 gallop on auscultation, with pansystolic murmur of MR and basal crepitations in the lower lung fields- pt may be in AF

Morphology

Dilated left ventricle

Edematous and congested lungs

M/E of lungs:

transudate in alveoli

Septal edema

Alveolar hemorrhage

Heart failure cells: macrophages with engulfed hemosiderin

chronic congestion of lungs causes brown induration due to hemosiderin and fibrosis

Lung – alveolar hemorrhage, heme-filled

macrophages “heart failure cells”, with

iron stain to right

Kidneys – reduced perfusion

Ischemic tubular necrosis / ATN

Prerenal azotemia

Kidney -ATN

Brain in CHF – cerebral hypoxia

Irritability

Loss of attention span

Restlessness

Stupor

Coma

Right-sided heart failure

Pure cor pulmonale

Can be a Consequence of left-sided failure

Myocardial – myocarditis, cardiomyopathy, constrictive pericarditis

Left to right shunt

C/F(clinical features)

Raised JVP (jugular venous pressure)

Pedal edema

Tender hepatomegaly

Pleural effusion and Ascites

In this case, there is hypertrophy of the right ventricular myocardium.

Pulmonary arterial intimal thickening in pulmonary hypertension.

This is a plexiform lesion - a pulmonary artery which is dilated and has multiple small

recanalized lumens. This lesion is characteristic of very severe pulmonary hypertension.

Cor Pulmonale

Right ventricular hypertrophy and dilatation secondary to pulmonary hypertension

Acute - right ventricular dilatation following pulmonary embolism

Chronic - right ventricular hypertrophy

Causes of Cor pulmonale

Disorders Affecting Chest Movement

Kyphoscoliosis

Marked obesity (pickwickian syndrome)

Neuromuscular diseases

Disorders Inducing Pulmonary Arterial

Constriction

Metabolic acidosis

Hypoxemia

Chronic altitude sickness

Obstruction to major airways

Idiopathic alveolar hypoventilation

Right failure - systemic effects

Liver –

chronic passive congestion

Centrilobular necrosis of hepatocytes causing nutmeg appearance on gross feature

Cardiac cirrhosis

Spleen – congestive splenomegaly

Kidneys – congestion and hypoxia

Subcut – peripheral edema and anasarca

Pleural space – effusions

Brain – venous congestion and hypoxia

Portal - ascites

Liver – chronic passive congestion – blood pools near the central veins

Liver – chronic passive congestion – red cell pooling near central veins

and pericentral necrosis of the hepatocytes

CHF – final pathway to death

Ischemic heart disease

Hypertensive heart disease

Valvular heart disease

Cardiomyopathy

Myocarditis

Specific heart muscle diseases