Pericardial diseases Flashcards
What is acute pericarditis?
Acute inflammation of the pericardium. Classically, fibrinous material is deposited into the pericardial space and pericardial effusion often occurs.
What are the causes of acute pericarditis?
CARDIAC RIND
- Collagen vascular disease
- Autoimmune / Aortic aneurysm
- Radiation
- Drugs
- Infection - Viral, bacterial
- AKI/Uraemia
- Cardiac infarction
- Rheumatic fever
- Injury / Idiopathic
- Neoplasm (malgnancy)
- Dressler’s syndrome
What are viral causes of acute pericarditis?
- Coxsackie
- Flu
- EBV
- Mumps
- Varicella zoster
- HIV
What are bacterial causes of acute pericarditis?
- Pneumonia
- Rheumatic fever
- TB
- Staphlococcus
- Streptococcus
What drugs can cause acute pericarditis?
- Hydralazine
- Penicillin
- Isoniazid
What are the most common causes of viral pericarditis?
Coxsackie B and echovirus
What is dressler’s syndrome?
An autoimmune response to cardiac damage occurring 2–10 weeks’ post-infarct. It is a type of pericarditis.
It is believed to result from an autoimmune inflammatory reaction to myocardial neo-antigens formed as a result of the MI. A similar pericarditis can be associated with any pericardiotomy or trauma to the pericardium or heart surgery.
How does pericarditis occur in uraemic patients?
Uraemia causes irritation of the pericardium due to accumulation of toxin. It can occur in 6–10% of patients with advanced kidney disease if dialysis is delayed.
What conditions is bacterial pericarditis associated with?
- Pneumonia
- Septicaemia
- Thoracic surgery
- Endocarditis
How does TB pericarditis present?
- Low-grade fever - particularly in the evening
- Features of acute pericarditis
- Dyspnoea
- Malaise
- Weight loss
- Night Sweats
What are the most common causes of malignant pericarditis?
- Carcinoma of the bronchus
- Carcinoma of the breast
- Hodgkin’s lymphoma
What are the symptoms of acute pericarditis?
Sharp Central chest pain
What are specific features of pericarditic chest pain?
- Exacerbated by movement, inspiration and lying down
- Relieved by sitting forward
What are the signs seen in pericarditis?
- Pericardial friction rub - LLSE
- Fever
- Features of pericardial effusion
What causes a pericardial friction rub?
https://www.youtube.com/watch?v=J1R8Oxgqhfk
Inflammation causes the pericardial and visceral surfaces of the pericardium (which are normally separated by a small amount of fluid) to rub together. It occurrs in three phases corresponding to atrial systole, ventricular systole and ventricular diastole. It may also be heard as a biphasic ‘to and fro’ rub.
The rub is heard best with the diaphragm of the stethoscope at the lower left sternal edge at the end of expiration with the patient leaning forward.
What symptoms can occur with a pericardial effusion?
Dyspnoea
What are signs of pericardial effusion?
- Raised JVP with prominenet x descent
- Soft heart sounds
- Pericardial friction rub
- Ewart’s sign
- If severe - signs of tamponade
What is Ewart’s sign?
A combination of the following signs:
- Dullness to percussion over the left scapula
- Aegophony (increased vocal resonance)
- Bronchial breath sounds over the left lung
What causes Ewart’s sign?
A large pericardial effusion can compress the left lung, causing consolidation and/or atelectasis, which alters percussive resonance. If the effusion enlarges sufficiently to collapse and/or consolidate the lung, increased vocal resonance and bronchial breath sounds will be heard.
Why can pericardial rub be present initially with a pericardial effusion, but the disappear as the effusion gets bigger?
Becomes quieter as fluid accumulates and pushes the layers of the pericardium apart
What is prominent x descent?
The x-descent occurs in the jugular venous waveform after atrial contraction, during ventricular systole, and is timed with the carotid pulse.
The x-descent represents the decrease in JVP, which occurs due to:
- Atrial relaxation
- Tricuspid valve being pulled downwards during ventricular systole
- Ejection of blood volume from the ventricles.
All of these aspects enlarge or relax the atrium, decreasing the atrial pressure. A prominent x-descent is faster and larger than normal. It is a sign that shows that forward venous flow only occurs during systole.
What is the mechanism behind a prominent x-descent in cardiac tamponade/pericardial effusion?
A prominent x-descent is an exaggeration of the normal waveform descent. In cardiac tamponade, compression of the chambers of the heart leads to elevated RA pressure. This raised pressure eventually blocks the forward flow of venous blood (i.e. filling) from the jugular vein into the atrium during diastole.
When the atrium relaxes and the ventricles contract in systole, the tricuspid valve is pulled down towards the apex of the heart, and there is a momentary increase in atrial volume and decrease in atrial pressure, allowing a rapid descent in atrial pressure and the JVP.
What are signs of cardiac tamponade?
- Tachycardia
- Hypotension
- Pulsus paradoxus
- Increased JVP
- Kussmaul’s sign
- Muffled heart sounds
What is pulsus paradoxus?
An inspiratory fall in systolic blood pressure exceeding 10 mmHg. It is elicited by inflating the blood pressure cuff to above systolic pressure and noting the peak systolic pressure during expiration. The cuff is then deflated until the clinician can hear the Korotkoff sounds during inspiration and expiration and this pressure value is noted. When a difference between these two pressures of greater than 20 mmHg occurs, pulsus paradoxus is present.
What is the mechanism behind pulsus paradoxus?
Fluid within the pericardial sac places pressure on all chambers of the heart and impairs LV filling but does not impair right ventricular filling to the same extent. Inspiration increases right ventricular filling compared to left ventricular filling, and the IV septum is pushed into the left ventricle, which further impairs left ventricular filling. When impaired LV filling is combined with pooling of blood in the lungs on inspiration, it exaggerates the normal decrease of LA and ventricular filling on inspiration. In addition to this, pulmonary venous pressure tends to be lower than the pressure in the left atrium, resulting in a decrease in left ventricular filling as more blood is pulled back towards the pulmonary veins.
What is kussmaul’s sign?
Rather than the expected decline in the level of jugular venous pressure on inspiration as venous blood is returned to the heart, a paradoxical rise in the JVP is seen when the patient breathes in.
What is the mechanism behind Kussmaul’s sign in cardiac tamponade/constrictive pericarditis?
Kussmaul’s sign is thought to be caused by a combination of increased venous return to the heart in conjunction with a constricted or non-compliant right ventricle, which cannot accommodate the venous return, and right atrial pressure exceeds the fall in pleural pressure. The blood then backs up into distended neck veins.
If you suspected acute pericarditis, what investigationss would you perform?
- ECG
- Bloods - FBC, U+E’s, ESR, Cardiac enzymes, viral serology, BCs, TFTs, autoantibody
- CXR
- ECHO
What might you see on ECG in someone with acute pericarditis?
- Widespread concave-upwards (saddle-shaped) ST elevation
- Reciprocal ST depression in leads aVR and V1
- PR segment depression
What is important to differentiate between when looking at an ECG in someone with suspected pericarditis?
If it is pericarditis or an MI
What might a CXR demonstrate in acute pericarditis?
Cardiomegaly from effusion
What might you see on ECHO in someone with acute pericarditis?
Pericardial effusion
If you suspected someone had a pericardial effusion, what investigations might you do?
Same as for acute pericarditis
What might you see on CXR in someone with a pericardial effusion?
Large globular or pear-shaped heart with sharp outlines
What might you see on ECG in someone with a pericardial effusion?
- Low voltage QRS
- Sinus tachycardia
- Electric alternans - alteration of QRS amplitude or axis between beats
What is the best method for visualising a pericardial effusion?
ECHO
If you suspected cardiac tamponade, what investigations would you do?
- CXR
- ECG
- ECHO
What are causes of cardiac tamponade?
- Any cause of pericarditis
- Aortic dissection
- Haemodialysis
- Warfarin
- Post cardiac biopsy
- Transeptal puncture on cardiac catheterisation
What is Beck’s triad?
Triad of features found in acute cardiac tamponade:
- Falling BP
- Rising JVP
- Muffled heart sounds
What might you see on CXR in someone with cardiac tamponade?
Big globular heart (>250ml fluid)
What might you see on ECG in cardiac tamponade?
- Low voltage QRS
- Electrical Alternans
What might you see on ECHO in someone with cardiac tamponade?
Echo-free zone around the heart +/- diastolic collapse of right atrium and ventricle
How would you manage someone with pericarditis?
- Treat the cause
- Analgesia - NSAIDs
How would you manage someone with a pericardial effusion?
- Treat the cause
- Pericardiocentesis - if large/tamponade - send fluid for culture
What could you use to treat an immune cause of pericarditis?
Cochicine +/- steroids
What is the risk with the use of steroids in pericarditis?
Increases risk of recurrence
How would you manage cardiac tamponade?
- Get help
- Pericardiocentesis
What is constrictive pericarditis?
Condition where the pericardial sac becomes heavily fibrosed and calcified. This results in a rigid, non-compliant casing for the heart. This disrupts the later filling stage of diastole, as the heart comes up against the rigid, unyielding pericardium
What are causes of constrictive pericarditis?
- Iatrogenic
- TB
- Haemopericardium
- Bacterial Infection
- Rheumatic Heart Disease
- Open surgery
- Dopamine agonists
Why is constrictive pericarditis not as immediately life-threatening as cardiac tamponade?
It is more chronic - the heart has time to compensate, compared with cardiac tamponade where the heart becomes acutely compromised
What do you need to distinguish constrictive pericarditis from?
Restrictive cardiomyopathy
What are the symptoms of constrictive pericarditis?
- Dyspnoea
- Cough
- Orthopnoea
- PND
- Fatigue
What are signs of constrictive pericarditis?
- Kussmaul’s sign
- Freidrich’s sign
- Pulsus paradoxus
- RHF - ascites, hepatosplenomegaly, raised JVP, dependent oedema
- Soft, diffuse apex
- Quiet heart sounds
- S3 heart sound
- Diastolic pericardial knock
- Hypotension
- Reflex tachycardia/AF
What is friedrich’s sign?
A faster and more prominent descent of the JVP during diastole, coinciding with the drop in right atrial pressure that occurs after opening of the tricuspid valve.
Seen on physical examination as an abrupt collapse of the neck veins during diastole.
What is the mechanism behind friedrichs sign?
In constrictive pericarditis, early diastolic filling is not inhibited but filling becomes impaired in the last two-thirds of diastole when the expanding ventricle hits the rigid pericardium. Once this occurs, the pressure rises again to a higher-than-normal level.
The y-descent appears accentuated as it descends from a higher-than-normal right atrial pressure.
What is the mechanism behind the diastolic pericardial knock heard in constrictive pericarditis?
The sudden slowing of blood flow into the ventricle in early diastole that occurs when the ventricle meets the rigid pericardial sac
Why can some people have AF in constrictive pericarditis?
Atrial dilatation
What investigations might you do in someone with suspected pericarditis?
- CXR
- ECG
- ECHO
- Cardiac MR
What might you see on CXR in someone with constrictive pericarditis?
- Relatively small heart
- Pericardial calcification
What might you see on ECG in someone with constrictive pericarditis?
- Low-voltage QRS complexes
- Generalized T wave flattening or inversion.
What might you see on ECHO in someone with constrictive pericarditis?
- Thickened calcified pericardium
- Small ventricular cavities with normal wall thickness
How would you manage constrictive pericarditis?
Complete surgical resection of the pericardium
What are the 3 D’s of cardiac tamponade?
- Distant heart sounds
- Distended jugular veins
- Decreased arterial pressure
