Infection Review

40%

Causes vegetation formation due to damage to the endocardial surface

Bacterial endocarditis

Endocarditis caused by microorganisms usually bacterial; most common being?

Streptococcus Viridans or Staphylococcus Aureus

What is most commonly affected with endocarditis?

Heart valves

With endocarditis - list the order of frequency from greatest to least affected

1. MV

2. AV

3. TV

4. PV

What is the most common underlying cardiac abnormality with endocarditis?

MVP

Endocarditis is also associated with?

1. CHD

2. Prosthetic valves

3. Surgical repairs

Patients with a history of IV drug abuse are high risk for?

Staphylococcus Aureus infection

Which valve is most commonly affected in IV drug users?

TV

This is preferred for the most sensitive assessment of vegetation formation (93-100%)

TEE

TTE is only about 80% sensitivity for vegetation identification because it cannot identify vegetations?

< 3 mm size

1. Fast onset of symptoms and infection progression

2. Related to Staphylococcus Aureus bacteria

3. High risk in IV drug users

Acute endocarditis

1. Delayed progression with chronic symptoms

2. Related to Viridans streptococcus

3. Prosthetic valve rings

4. Cyanotic heart disease

Subacute endocarditis

Classic triad of signs/symptoms of endocarditis

1. Fever of unknown origin

2. New onset of a murmur

3. Positive bacterial cultures

1. Most common valve infection

2. Vegetations > 10 mm diameter found on the valve

3. Forms on the atrial side (flow side) of the valve and ruptured chordae

4. Related to flail leaflet on ventricular side of the valve

5. Prolapses into LA during systole

MV vegetations

1. Frequently involves congenitally malformed leaflets or leaflets deformed by rheumatic heart disease

2. Located on ventricular side of leaflets (flow side of valve)

3. Can be seen prolapsing into LVOT during diastole and flopping back into aorta during systole

AV vegetations

What can be mistaken for an AV vegetation?

Lambl excrescence

Normal aortic leaflet thickening at the central coptation region can also be mistaken for a vegetation

Nodule of Aratius

1. Most common in patients with history of IV drug abuse (staph aureus most common)

2. Present with fever and evidence of pulmonary emboli

3. Located on atrial side of valve

4. Prolapses into RA during systole

TV vegetations

1. Uncommon as an isolated finding

2. Located on ventricular side of valve

Pulmonic vegetations

1. Shaggy or fuzzy appearance on m-mode

2. Most commonly cause regurg of affected valve

3. Pericardial effusion

4. Valve ring abscess is potential complication

Endocarditis

Inflammation of the myocardium

Myocarditis

1. Usually leads to ventricular dysfunction or DCM

2. Cardiomegaly

3. PVCs

4. Ventricular tachycardia

5. Small pericardial effusion

Myocarditis

1. Causes non-bacterial wart like lesions on the valves (Libman-Sacks) that’s indistinguishable from vegetations

2. Lesions may cause valvular regurgitation and rarely stenosis

3. May require valvular replacement

Lupus

Libman-Sacks endocarditis AKA?

Marantic endocarditis (non-bacterial thrombotic endocarditis)

Marantic endocarditis only affects?

Valves (no involvement of myocardium or other cardiac structures)

Inflammation of the outer layer of tissues surrounding the heart

Pericarditis

What causes pericarditis?

1. Infection

2. Neoplasm

3. Inflammatory disease

4. Radiation treatment

5. Chronic steroid use

6. Recent cardiac surgery

Delayed form of pericarditis that occurs 1-12 weeks after MI

Dressler syndrome

Most common symptom of acute pericarditis

Positional chest pain

1. Leads to pericardial fluid formation

2. Pericardial thickening difficult to diagnose with sonography

3. Pericardectomy used for those with chronic pain

Pericarditis

1. Pericardial rub - friction rub

2. Widespread ST elevation

Pericarditis

Chronic inflammatory processes of the pericardium may cause calcification, adhesions and fibrosis with thickening of the pericardial layers

Constrictive pericarditis

With constrictive pericarditis, these fibrous changes limit the ability of the diastolic expansion of the cardiac chambers causing?

Restricted diastolic filling (knocking sound)

Most commonly idiopathic or complication of pericardiotomy

Constrictive pericarditis

What is the best way to diagnose constrictive pericarditis?

Cardiac catheterization

With constrictive pericarditis, post-pericardiectomy heart will demonstrate?

Increased cardiac motion in the chest

Signs and symptoms of constrictive pericarditis

1. Dyspnea

2. Ascites

3. Jugular vein distention

4. Pericardial knocking murmur

1. > 3 mm thickness without effusion (normal thickness 1-2 mm)

2. 2D/m-mode show IVS bounce during diastole (helps to disguise from restrictive cardiomyopathy)

3. Flattening of posterior/inferior wall of LV during diastole

4. LA can be enlarged

5. Dilated IVC (plethora), IJV and HPVs

Constrictive pericarditis

Constrictive pericarditis can cause premature opening of the?

PV (prior to the onset of atrial systole)

Doppler findings of this include

1. Increased RV pressure during diastole causes PV to open prematurely during systole

2. Respiratory variation in RV/LV (MV/TV inflow velocities)

3. Diastolic dysfunction (E/A ratio > 1.5 restrictive flow pattern)

4. Exaggerated E-F slope

5. Prolonged IVRT

6. Dilated IVC with little to no respiratory collapse and HPVs with diastolic flow reversal with expiration

Constrictive pericarditis

Constrictive pericarditis will demonstrate a prominent?

A wave on the PV waveform and reduced systolic velocity (S wave)

Tissue Doppler of constrictive pericarditis will show?

1. E velocity usually normal

2. E/E’ < 8

3. May see small or absent A peak

4. Annulus reversus