Haemorrhagic Pericardial Effusion

Haemorrhagic pericardial effusion is blood or blood stained fluid in the pericardial sac. Frank haemopericardium is the acute form, usually from rupture or perforation, and carries a high risk of tamponade. Blood stained effusion from inflammatory or malignant disease accumulates more slowly.

Tamponade depends on the rate of accumulation more than the volume. An acute collection of 100 to 200 mL can cause tamponade, while a slow collection of 1 to 2 litres may be tolerated.

Causes by frequency in non-traumatic series are malignancy, tuberculosis (the leading cause in sub-Saharan Africa and parts of Asia), uraemia and post-cardiac injury syndromes. Acute haemopericardium follows iatrogenic injury (cardiac surgery, coronary intervention, ablation, lead implantation, transcatheter valve procedures, pericardiocentesis), blunt or penetrating chest trauma, type A aortic dissection, and post-infarction free wall rupture.

Anticoagulants, antiplatelet drugs and coagulopathy (thrombocytopenia, liver disease, uraemia) increase the risk and the volume of bleeding. Radiation, bacterial pericarditis and connective tissue disease are less common causes.

Size is graded on diastolic echo free space: small under 10 mm, moderate 10 to 20 mm, large over 20 mm.

Pathophysiology.

The pericardium is stiff and has a steep pressure volume relationship. Once its reserve volume is exceeded, intrapericardial pressure exceeds right sided filling pressures, and then left sided pressures, so cardiac output falls.

Blood in the pericardium is partly defibrinated by cardiac motion, but in acute bleeding it clots, causing loculation and making drainage difficult. Fibrin and organising clot cause adhesions and constriction, including effusive constrictive disease, in weeks to months.

In tuberculosis and malignancy, new vessels in inflamed or invaded pericardium bleed continuously, so recurrence after drainage is frequent.

Dyspnoea, orthopnoea, chest pain, fatigue, presyncope and abdominal discomfort. Tamponade gives tachycardia, hypotension, raised jugular venous pressure with a preserved x descent and absent y descent, muffled heart sounds (Beck triad, present in a minority), narrow pulse pressure, pulsus paradoxus (inspiratory fall in systolic pressure over 10 mmHg), oliguria and cool peripheries. Pulseless electrical activity is the usual arrest rhythm.

Context gives the cause: tearing chest or back pain (dissection), fever, night sweats and weight loss (tuberculosis), known cancer, dialysis, anticoagulant use, a recent procedure or chest trauma.

• Echocardiography at the bedside: echo free space with echogenic clot or fibrin strands, right atrial and right ventricular diastolic collapse, plethoric inferior vena cava, and respiratory variation in inflow (mitral over 25%, tricuspid over 40%).
• ECG: sinus tachycardia, low voltage, electrical alternans.
• CT chest: fluid density over 30 Hounsfield units suggests blood, and CT shows dissection, tumour, lymphadenopathy and the site of perforation.
• Blood tests: full blood count, platelets, PT and INR, aPTT, anti-Xa level, fibrinogen, urea and creatinine, troponin, TSH, HIV test, blood cultures, group and cross-match.
• Fluid analysis after drainage: haematocrit (fluid haematocrit is usually well under the peripheral value), cell count, protein (over 30 g/L is an exudate), LDH, adenosine deaminase (over 40 U/L suggests tuberculosis), Xpert MTB/RIF and mycobacterial culture, bacterial culture, cytology (positive in 60 to 90% of malignant effusions) and tumour markers.
• Pericardial biopsy by surgical window or thoracoscopy when the cause remains unknown after fluid analysis.

Differential diagnosis.

• Pericardial effusion from non-haemorrhagic causes with blood contamination during aspiration.
• Intracardiac position of the needle or catheter (agitated saline and pressure waveform confirm site).
• Loculated pleural effusion, mediastinal haematoma and pericardial cyst.
• Pericardial tumour and constrictive pericarditis.

Tamponade with shock (emergency).

• Oxygen, intravenous access, arterial line and continuous monitoring. Crystalloid 250 to 500 mL intravenously over 10 to 15 minutes to support filling while drainage is arranged. Noradrenaline 0.05 to 0.5 microgram/kg/min if hypotension persists, to keep mean arterial pressure over 65 mmHg.
• Avoid diuretics, vasodilators, beta blockers and sedatives. Avoid intubation and positive pressure ventilation where possible, since they can precipitate arrest. If intubation cannot be avoided, use an experienced operator with ketamine 1 to 2 mg/kg and noradrenaline running.
• Drain urgently. Percutaneous pericardiocentesis under echocardiographic control (subxiphoid or apical, 6 to 8 Fr pigtail catheter) suits non-traumatic and catheter laboratory tamponade. Surgical drainage (subxiphoid window or sternotomy) is chosen for trauma, aortic dissection, post-cardiac surgery bleeding, clotted or loculated effusion, and recurrence. Resuscitative thoracotomy is used for traumatic arrest.
• Remove fluid in stages in large effusions (about 1 litre at first), to avoid pericardial decompression syndrome (acute ventricular failure and pulmonary oedema).
• Type A aortic dissection with tamponade: emergency surgical repair. If the patient is peri-arrest, remove only enough blood to keep systolic pressure at about 90 mmHg, because full drainage can restart bleeding.
• Transfuse red cells, plasma and platelets by need. In iatrogenic perforation in the catheter laboratory, drained blood can be returned intravenously.

Reverse anticoagulation.

• Warfarin: four factor prothrombin complex concentrate 25 units/kg (INR 2 to under 4), 35 units/kg (INR 4 to 6) or 50 units/kg (INR over 6), with vitamin K 5 to 10 mg intravenously slowly.
• Unfractionated heparin: protamine 1 mg for each 100 units of heparin given in the previous 2 to 3 hours (maximum single dose 50 mg), given slowly to avoid hypotension; check aPTT.
• Dabigatran: idarucizumab 5 g intravenously (two 2.5 g infusions).
• Apixaban and rivaroxaban: andexanet alfa where available (low dose regimen of 400 mg bolus then 4 mg/min for up to 120 minutes, or high dose regimen of 800 mg bolus then 8 mg/min for up to 120 minutes, chosen by the inhibitor, its dose and time since the last dose), or prothrombin complex concentrate 50 units/kg.
• Hold antiplatelet drugs while bleeding. Restart only when haemostasis is secure and an indication exists.

Treat the cause.

• Iatrogenic coronary or chamber perforation: stop heparin, reverse it, drain, and use a covered stent, embolisation or surgery when bleeding persists after drainage.
• Tuberculosis: isoniazid 5 mg/kg (maximum 300 mg), rifampicin 10 mg/kg (maximum 600 mg), pyrazinamide 25 mg/kg (maximum 2 g) and ethambutol 15 mg/kg (maximum 1.2 g) orally once daily for 2 months, then isoniazid and rifampicin once daily for 4 months, with pyridoxine 25 mg daily. Liver tests at baseline, 2 weeks and monthly; stop the hepatotoxic drugs if ALT exceeds 3 times the upper limit of normal with symptoms or 5 times without. Check visual acuity and colour vision on ethambutol, and adjust pyrazinamide and ethambutol to three times weekly dosing when creatinine clearance is under 30 mL/min. Rifampicin lowers the effect of warfarin (increase dose, check INR often), direct oral anticoagulants and antiretrovirals. Adjunctive prednisolone reduces constriction but not death, and in HIV it increased cancers; it is not routine. Where a specialist chooses it, the usual schedule starts at 60 mg daily and tapers over about 11 weeks.
• Uraemic effusion: intensify dialysis (daily, heparin free) for 7 to 14 days. Drain for tamponade. Surgical window for recurrence.
• Malignant effusion: drain with an indwelling catheter for 3 to 7 days, treat the tumour, and consider pericardial window for recurrence.
• Post-infarction free wall rupture: emergency surgery.
• Purulent pericarditis: surgical drainage and vancomycin 25 mg/kg load then 15 to 20 mg/kg every 8 to 12 hours (trough 15 to 20 mg/L) with piperacillin and tazobactam 4.5 g intravenously every 6 hours, adjusted to cultures.

Monitoring. Echocardiography 24 to 48 hours after drainage and before drain removal (drain output under 25 mL in 24 hours), then at 1 week, 1 month and 3 months. Haemoglobin and coagulation every 6 to 12 hours while bleeding. Watch for effusive constrictive disease.

Referral and escalation. Any patient with tamponade physiology needs same hour drainage with cardiothoracic back up. Refer immediately for trauma, dissection, post-surgical bleeding, haemodynamic instability or reaccumulation. Refer to cardiology and oncology for undiagnosed bloody effusion.

Special groups.

• Pregnancy: left lateral tilt; dissection and peripartum causes are possible; drain under multidisciplinary care; avoid warfarin.
• Children: tuberculosis dosing is isoniazid 10 mg/kg (range 7 to 15), rifampicin 15 mg/kg (range 10 to 20), pyrazinamide 35 mg/kg (range 30 to 40) and ethambutol 20 mg/kg (range 15 to 25) daily.
• Kidney impairment: reverse heparin effect with care, give pyrazinamide and ethambutol three times weekly when creatinine clearance is under 30 mL/min, and dialyse without heparin.
• Region specific: test for HIV and tuberculosis in every patient with a bloody effusion in endemic areas.