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On completion of this case and associated learning activities you should be able to:

state the causes of a failing heart

Patients with established heart failure have median survival rates of ~3yrs.

Early diagnosis of compensated HF is difficult.

HF is the end result of heart disease.

PATHOPHYS

The main problem that starts everything off is the reduction of cardiac output that causes underperfusion

in the systemic circuit.

The body responds to this in various ways:

MECHANORECEPTORS (aortic arch, LV wall, carotid sinus, renal afferent arterioles) start firing to the

cardioreg centres in brain (via CN9 &10)

+

BRAIN activates symp nervous system - i.e. tachycardia, vasoconstriction (arterial and venous), incr

contractility

+

RAS activated causing renal vasoconstriction+

HYPOTHALAMUS releases vasopressin (ADH)

= retention of Na and H20

CONSEQUENCES

Remodelling occurs of the ventricles: i.e. changes in size, shape and composition. This is a poor

prognostic feature.

HOW TO CATEGORIZE HEART FAILURE

Acute vs Chronic

ACUTE HF develops within minutes of an MI. Findings: pulm odema, acute, severe SOB. chronic congestive HF can occur after an MI

CHRONIC HF is sequelae of valve disease e.g. mitral stenosis. (over years)

Left vs Right

One eventually causes the other though.

Cor pulmonale = RH failure secondary to lung disease (most commonly COPD, also mitral stenosis)

Mech: as lung tissue is destroyed, capillary bed is reduced, so normal CO is pumped into a smaller volume

of tissues, so pulm pressure rises. Hypoxia causes reflex pulm vasoconstriction, further inc vascular pulm

pressure. Inc vascular pulm pressure causes fluid to transudate from capillaries to alveoli (the interstitial

tissues of the lung)

Low output vs High output

LOW OUTPUT is when the CO cant be increased even in exercise and then decreases even at rest.

HIGH OUTPUT is when there is pulm congestion and odema leading to normal CO and LV ejection fraction

(or even increase)

-causes: preg, XS salt and water from steroids, others e.g. cirrhosis, hyperthyroidism

Systolic vs diastolic

Diagnosis thru echo.

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SYSTOLIC is when ejection fraction is reduced

DIASTOLIC is when ventricular filling is reduced in diastole.

DIAGNOSING

Echo - transthoracic. most sen and spe

CAUSES

-IHD

-sytemic hypertension

-valvular heart disease

-lung disease -> RH failure -> congestive heart failure

correlate clinico-pathologic findings with a cause of heart disease

SOB, fatigue, peripheral oedema, claudication, elevated JVP, pulmonary oedema, malaise (non specific:

N&V, fatigue, diff sleeping, headache)

Echo is gold standard for diagnosis

dyspnoea:-pink frothy fluid from pulm congestion and oedema from mouth, nose

OR rusty brown, blood stain sputum bc of alveolar haemmorhage

-crackles on auscultation

-orthopnea (inc VR from periphery and gut when lying down causes SOB) and PND are classic signs of

LVF

Venous congestion and oedema

-Hepatomegaly and assoc fatty changes to hepatocytes due to ischaemia result in nutmeg liver see

Fig13.21 pg 293

-LFT abnormalities

HF is a common cause of pre-renal ARF. Proteinuria common.

discuss the pathology and aetiology of cardiomyopathies with specific reference to infiltrative

cardiomyopathy

Cardiomyopathy is a heart MUSCLE disease of uncertain cause - but genetic cause is indicated in new

research.

Diagnosis made when all others are excluded.

Dilated or hypertrophic pattern of diseasese

there are some causes of cardiomyopathy that are treatable or somewhat reversible - e.g.

haemachromatosis, hyperthyroidism, hypothyroidism

DILATED CONGESTIVE CARDIOMYOPATHY (DSCM)Presentation at ~50, but young adults can too

ventricles dilated and hypertrophied, but coronary arteries have no significant atheroma.

Similiar pathologically to chronic alcoholic heart disease

Poor outlook: 50-60% of px survive to 2 years

Look for underlying cause e.g. aortic valve diseaese

Young px - transplant suitable. Fig 13.46 pg 314

HYPERTROPHIC OBSTRUCTIVE CARDIOMYOPATHY (HOCM)

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Common autosomal dominant disorder

Left ventricular hypertrophy (as opposed to both in DSCM) - most marked usually in interventricular

septum.

Presents clinically after pubertal growth phase/early adult life, variety of presentations.

Complications: AF, ventricular arrhythmias, sudden death

ARRHYTHMOGENIC RIGHT VENTRICULAR CARDIOMYOPATHY (ARVC)

strong familial tendency, less common that two above

after HOCM commonest cause of unexpected cardiac death in young fit people

progressive loss of RV myocytes & assoc fibrosis, inflamm and adipose tissue replacement

OTHERS

Peurperal cardiomyopathypregnancy related, last months of preg or within 6 months of delivery.

Sometimes resolves.

Restrictive cardiomyopathyrestricted filling and dec diastolic filling of 1 or both ventricles. Causes:

myocardial or endocardial disease that stiffens the heart by fibrosis or infiltration. Sometimes no cause.

identify causes of heart muscle pathology that are not due to: ischaemia, hypertension, cardiacvalve disease, inflammatory causes, toxins, metabolic disease or neuromuscular disease

evaluate the cause, effect and clinico-pathologic correlation of amyloid

Amyloid is the name of a GROUP of proteins that share the following characteristics when they are

deposited in tissues:

-they are B-pleated sheets with an affinity for certain dyes, e.g. Congo Red or Sirius Red. This is important

- bc the body doesnt have enzymes that can digest large molecules like B-pleated sheets. This

means they stay in the tissues permanently.

-Fibrillar ultrastructure

-Presence of a glycoprotein (amyloid P protein) of some family.

-located extracellularly, often of basement membranes

-are resistant to being removed by natural processes-have a tendency to cause the affected tissue to become hardened and waxy

On the otherhand you can get small, asymptoamtic deposits in spleen, brain, heart, joints of elderly people.

review an investigative pathway of amyloidosis

You can classify amyloid according to its chemical composition (i.e. the amyloid substance) its tissue

deposition or its aetiology (if known).

CLINICAL PRESENTATION

This can be systemic or localized.

Systemic

material is deposited in lots of organs - practically none are left out.

-generalized diffuse organ enlargement e.g. hepatomegaly, splenomegaly, macroglossia

-evidence of organ dysfunction - e.g. HF, proteinuria

Classified according to its aetiology, i.e. myeloma-associated(primary), reactive (2dary) senile, haemo-

dialysis assoc or hereditary.

Amyloidosis is a serious complication of myeloma. In primary disease the amyloid deposits are

immunoglobulin light chains

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Chronic inflamm disorders predispose to 2dary amyloidosis, e.g. rheumatoid disease, bronchiectasis and

osteomyelitis. In 2dary amyloidosis the material is serum amyloid protein A.

Localized

cerebral amyloid = alzheimers

amyloid material found in stroma of tumours that produce peptide hormones - particuarly characteristic of

medullary carcinoma of the thyroid

you may also find localized deposits for no apparent cause in any organ - but this is rare. Skin, lungs and

urinary tract are the most common.

CLINICAL EFFECTS

-nephrotic syndrome and then RF

-hepatosplenomegaly

-macroglossia

-purpura

-carpal tunnel

-cardiac failure

-coagulation factor X defiency (in AL amyloid)

TESTING

biopsy of rectal mucosa, stain with Congo or Sirius red dyes or antibodies in immunohistological testing