January 26, 2016 - The Cardiomyopathies Flashcards Preview

COURSE 3 > January 26, 2016 - The Cardiomyopathies > Flashcards

Flashcards in January 26, 2016 - The Cardiomyopathies Deck (15):
1

Systolic Dysfunction

Myocytes have decreased contractile function (weak squeeze)

2

Diastolic Dysfunction

The myocytes contract normally, however cannot fully relax. This leaves the ventricles "stiff" and unable to fill properly.

3

Dilated Cardiomyopathy

Characterized by enlargement of the ventricular chambers.

Chief hemodynamic disturbance is systolic impairment.

4

Causes of Dilated Cardiomyopathy

Primary - idiopathic, genetic, and peripartum

Secondary - infection (myocarditis), toxins, inflammatory diseases, metabolic

5

Myocarditis

Inflammation of the myocardium (often from infectious agents).

Usually self-limiting, but can result in dilated cardiomyopathy.

6

Peripartum Cardiomyopathy

Presents with heart failure symptoms between the last month of pregnancy and up to 6 months post-partum.

Unclear etiology, but risk factors include older age, african descent, and multiple pregnancies.

50% have a return to normal ventricular function.

7

Pathophysiology of Dilated Cardiomyopathy

Inflammatory process leads to decreased contractile function...

Which leads to decreased stroke volume...

Which leads to increased left ventricular diastolic pressure...

Which leads to a dilated ventricle...

Which leads to more decreased contractile function...

 

VICIOUS CYCLE

8

Heart Failure Symptoms

Weight gain

Abdominal bloating

Early satiety

Leg swelling

Fatigue

Dyspnea

Orthopnea

PND (noctunal dyspnea)

Lightheadedness

Syncope

9

Heart Failure Signs

Elevated JVP

Hepatomegaly

Ascites

Peripheral edema

Hypoxia

Tachypnea

Inspiratory crackles

Decreased LOC

Cool extremities

Low urine output

S3

Palpable / Loud S2

10

Hypertrophic Cardiomyopathy (HCM)

Thickened myocytes contract well but are "stiff" and cannot relax. This leads to problems filling the ventricle.

Most common cause of sudden death in athletes.

Incidence of 1/500 --> Autosomal Dominant

Characterized by asymmetric or symmetric thickening of ventricular walls

11

Hypertrophic Obstructive Cardiomyopathy (HOCM)

When there is dynamic obstruction of the LV outflow tract by the mitral valve leaflet. The mitral valve physically blocks the outflow tract and prevents blood from leaving into the aorta.

12

Hypertrophic Cardiomyopathy - Treatment

Decrease contractility - B-blockers, CCB

Possible myomectomy or septal ablation

Treat arrhythmias

Avoid low preload or afterload

13

Restrictive Cardiomyopathy

Characterized by abnormally rigid (not necessarily thick) ventricular walls. This causes abnormal filling because of the lack of contractility.

Less common but is the extreme of diastolic dysfunction.

Most common cause is amyloidosis.

14

Cardiac Amyloid

Most common in primary (AL) form of amyloid.

Results in reduced ventricular compliance and increased LVEDP. This in turn, increases pulmonary venous pressure, as well as decreases stroke volume and cardiac output.

15

Restrictive Cardiomyopathy - Physical Exam

Elevated JVP with prominant x and y

Low voltages on ECG

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