PERICARDIAL FLUID PERICARDIAL SAC Outer parietal pericardium Inner visceral pericardium In btw pericardial fluid is present NORMAL :15-50 mL
PERICARDIAL EFFUSION PUTS PHYSICAL PRESSURE ONTO THE HEART Symptoms: Chestpain SOB Malaise Cause: Any process causing inflammation or injury to pericardium Any process affecting lymphatic drainage of fluid
CARDIAC TAMPONADE Increased intrapericardial pressure reduces cardiac function COMPRESSION OF HEART by rapid accumulation of fluid in pericardial sac
PERICARDIAL SAC WITHSTAND Slow,progressive,long term effusion: upto 1500 mL ( without showing symptoms ) Acute effusion: 100-200mL blood suddenly entering pericardium ( patient symptomatic ) NOTE: Affects the cardiac hemodynamics by creating equilibrium of diastolic pressures in all 4C
MECHANISM
PHYSICAL EXAMINATION Tachycardia Pulsus paradoxus Becks triad Hypotension Elevated JVP Muffled HS COMPLICATIONS HF Pulmonary edema Shock Death Therefore cardiac tamponade is a medical emergency Treated with pericardiocentesis CARDIAC ETIOLOGIES Dissection of aortic aneurysm End stage lung cancer Acute MI Cardiac surgery Pericarditis ASYMPTOMATIC EFFUSIONS Hypothyroidism Uremia, Collagen vascular diseases ( lupus,rheumatoid arthritis,scleoderma etc..)
ECG ELECTRICAL ALTERNANS SINUS TACHYCARDIA LOW VOLTAGE
X RAY
ECHO
ECHO Findings: Pericardial effusion Diastolic right ventricular collapse Systolic right atrial collapse Plethoric IVC with minimal respiratory variation Exaggerated respiratory cycle changes in mitral and tricuspid valve in-flow velocities as a surrogate for pulsus paradoxus
1.Pericardial effusion Heart swinging within pericardial sac size of the effusion does not necessarily predict pericardial tamponade. More important in predicting tamponade are the rate of rise of the effusion and the pericardial compliance
No diastolic collapse in a chronic pericardial effusion Once the pericardium’s compliance reaches a certain threshold, even a small increase in pericardial fluid can lead to tamponade.
2.Right ventricular collapse The right ventricle (RV) collapses when the intra pericardial pressure exceeds the intra cardiac pressure. The severity of tamponade is correlated with the duration of the chamber’s collapse The outflow region collapses first, followed by the basal segment once tamponade progresses. diastolic collapse will less likely occur in conditions like acute or chronic cor pulmonale, pulmonary hypertension, severe LV failure, or other etiologies of RV hypertrophy. Positive-pressure ventilation will exert this effect as well.
Distinct downward motion of the right ventricular free wall (larger arrow) in early diastole . A s the mitral valve (MV) opens to indicate diastole, the RV outflow tract (RVOT) anterior wall can be seen collapsing downward.
M mode End systole is noted by the large downward-pointing arrow, after which there is further collapse of the right ventricular-free wall (small arrow) in early diastole. Mitral valve opening indicates diastole
3.Right atrial collapse The RA is at its lowest pressure during systole, or more precisely, in late diastole at the onset of atrial relaxation. Its pressure during systole is lower than that of the RV in diastole, so systolic RA collapse is therefore the earliest echocardiographic sign of tamponade The sensitivity for tamponade is higher, ranging from 50% in early tamponade to 100% with its progression Systolic RA collapse in the SX view
4.P lethoric IVC Defined as dilation of the IVC and hepatic veins with < 50% reduction in diameter during inspiration A plethoric IVC can be visualized in the subcostal plane . The diameter should be measured about 2-3 cm from the IVC-RA junction, usually around the level of the hepatic vein draining into the IVC
5.DOPPLER Respiratory variation Pulsus paradox (Ventricular interdependence) During inspiration, expect a >25% decrease in MV in-flow velocity, and a 40% increase in TV in-flow velocity.
1 2 E I I E
Management Medications and IV to improve blood pressure Supplemental oxygen to reduce load Pericardiocentesis
Pericardiocentesis Pericardiocentesis, also called the pericardial tap, is an invasive procedure performed to remove excessive pericardial fluid from the pericardial sac. It is often performed in the setting of pericardial tamponade to correct hypotension due to decreased stroke volume from extrinsic compression of the chambers of the heart. Removal of 5-10ml may dramatically improve the stroke volume and cardiac output by 25-50%.
Indications Pericarditis Trauma Cardiac Tamponade
Echocardiography The echocardiography-guided approach allows defining the position of the effusion, the ideal entry site and needle trajectory for pericardiocentesis. There are two different approaches to echo guidance: The first is the echo-assisted method, in which the operator memorises the optimal needle trajectory and advances the needle towards the pericardial space without a continuous ultrasound visualisation. The second approach is the echo-guided method with a continuous echocardiographic monitoring. It has also been proposed to use a needle carrier mounted on the ultrasound transducer to advance the needle to the pericardial space.
Approaches for pericardiocentesis Place of Puncture Apical Description The needle insertion site is 1-2 cm lateral to the apex beat within the fifth, sixth or seventh intercostal space. Advance the needle over the superior border of the rib to avoid intercostal nerves and vessels. Disadvantages Risk of ventricular puncture due to the proximity to the left ventricle. Increased risk for pneumothorax for the proximity to the left pleural space. Advantages The thicker left ventricle wall is more likely to self-seal after puncture. Due to ultrasound not penetrating air, using echocardiographic guidance ensures avoidance of the lung. The path to reach the pericardium is shorter.
Place of Puncture Parasternal Description The needle insertion site is in the fifth left intercostal space close to the sternal margin. Advance the needle perpendicular to the skin (at the level of the cardiac notch of the left lung). Disadvantages Risk of pneumothorax and puncture of the internal thoracic vessels (if the needle is inserted more than 1 cm laterally). Advantages Echocardiographic guidance, also with phase array probe, provides a good visualisation of pericardial structures.
Place of Puncture Subxiphoid Description The needle insertion site is between the xiphisternum and left costal margin. Once beneath the cartilage cage, lower the needle to a 15-to-30-degree angle, with the abdominal wall directed towards the left shoulder. Disadvantages A steeper angle may enter the peritoneal cavity, and a medial direction increases the risk of right atrial puncture. In some cases, the left liver lobe may be transversed intentionally if an alternative site is not available. The path to reach the fluid is longer. Advantages Lower risk of pneumothorax.