Pericardial Effusion and Cancer

A pericardial effusion is extra fluid inside the pericardium, the thin sac that wraps around the heart. NCI's patient summary defines it as "extra fluid inside the sac around the heart" and adds that "the extra fluid causes pressure on the heart, which stops it from pumping blood normally." When cancer is the cause, teams call it a malignant pericardial effusion.

That sac normally holds very little. NCI's health-professional summary puts normal pericardial fluid at roughly 15 to 50 mL, which is a few tablespoons. Its job is to let the heart slide smoothly as it beats.

Cardiac tamponade is what happens when the fluid presses hard enough that the heart cannot fill between beats. NCI states it plainly: "In cardiac tamponade, the heart cannot pump enough blood to the rest of the body. This is life-threatening and must be treated right away."

Call 911, or go to an emergency department now, if any of these appear:

• Breathlessness at rest, or breathlessness that is suddenly worse.
• Sharp chest pain. MedlinePlus notes it may be "felt in the neck, shoulder, back, or abdomen."
• Fainting, near-fainting, or new lightheadedness when you stand.
• Fast breathing, or a heart that is racing.
• Skin that turns "pale, gray, or blue."
• New anxiety or restlessness that you cannot settle.
• New swelling in the legs or the belly.

MedlinePlus leaves no room for doubt on tamponade: "Go to the emergency room or call the local emergency number (such as 911) if symptoms develop."

Three findings a clinician looks for together are low blood pressure, neck veins that bulge, and heart sounds that are faint. You cannot check those at home. They are worth knowing about because they explain why a team may move fast on breathlessness that seems mild to you.

Call your team the same day if you run a temperature of 100.4°F (38°C) or higher. CDC's guidance for people with cancer is direct: "Call your doctor immediately if you have a temperature of 100.4ºF (38ºC) or higher." CDC adds that "fever may be the only sign that you have an infection." This matters most in the days after any drainage procedure.

How much fluid is there is the wrong first question. How fast it arrived is the right one.

The sac can stretch if it is given time. NCI's health-professional summary says that "hemodynamic compromise occurs when the normal amount of pericardial fluid increases to 200 mL to 1,800 mL." Hemodynamic compromise means the heart can no longer keep blood moving properly. That is a very wide range, and the reason is stretch.

But when fluid arrives quickly, the sac has no chance to give. NCI notes that rapid build-up can cause tamponade with as little as 250 mL. So a small effusion that appeared over two days can be far more dangerous than a large one that took three months.

Ask your team both questions: how big is it, and how fast did it come.

NCI's health-professional summary explains the mechanism: malignant involvement of the pericardium is the most common reason effusions develop, and they "result from blockage of venous and lymphatic circulation of pericardial fluid." Fluid is made at the normal rate but cannot drain away, so it collects.

The cancers behind it are not evenly spread. NCI reports that one-third of pericardial metastases are caused by lung cancer, that breast cancer causes 25% of pericardial effusions, and that blood cancers — leukemia, Hodgkin disease and non-Hodgkin lymphoma — cause 15% of malignant pericardial effusions. Radiation therapy to the chest can also lead to fluid around the heart, as MedlinePlus notes among the causes of tamponade.

Breathlessness dominates. NCI reports dyspnea, meaning shortness of breath, in 93% of patients with pericardial effusions. Cough and chest pain are common too.

Orthopnea also shows up on that list. Orthopnea is breathlessness that comes on when you lie flat and eases when you sit up. If you have started sleeping on more pillows, or moved to a recliner, that is a symptom and not a preference. Say it out loud at your next call.

MedlinePlus adds anxiety and restlessness to the tamponade picture. Caregivers often notice that before the person does.

Echocardiogram. This is an ultrasound scan of the heart, and it is the main test. MedlinePlus says of tamponade that "an echocardiogram is the test of choice to help make the diagnosis." NCI explains that "transthoracic echocardiography using apical, subxiphoid, and parasternal views can evaluate the presence, quantity, and quality of suspected pericardial effusions." Those three words are just the spots on your chest where the probe is placed.

ECG. An electrocardiogram records the heart's electrical activity through stickers on the skin. NCI describes electrical alternans, a beat-to-beat change in the size of the tracing, as a classic but uncommon finding in large effusions. It happens because the heart is swinging inside a pool of fluid.

Chest x-ray. NCI notes that a chest x-ray may show widening of the heart shadow once the fluid passes about 250 mL, but adds that an x-ray cannot show how much the heart is being squeezed.

Pericardiocentesis is the needle drainage procedure. MedlinePlus describes it step by step. The doctor cleans "an area just below or next to the breastbone or below the left nipple" and numbs it. A needle is guided in, often using "echocardiography (ultrasound)" along with ECG and x-ray guidance. Once the needle is in the right place, "it is removed and replaced with a tube called a catheter." Fluid drains into containers, and usually "the pericardial catheter is left in place so draining may continue for several hours."

Practical points from the same page: you may not be able to eat or drink for six hours beforehand, and you will sign a consent form. "You may feel pressure as the needle enters. Some people have chest pain, which may require pain medicine."

The listed risks are real and worth hearing before you agree: bleeding, collapsed lung, heart attack, infection, irregular heartbeats, puncture of the heart muscle, a coronary artery, the lung, liver or stomach, and air trapped in the sac.

The fluid that comes out is not just discarded. MedlinePlus notes the procedure is "most often done to find the cause of a chronic or recurrent pericardial effusion." The lab looks for cancer cells and for infection.

Draining once often is not the end of it. NCI lists several options for effusions that refill: pericardial sclerosis, which uses a medicine to seal the sac shut; pericardiotomy and pericardial window, surgical openings that let fluid escape into a space where the body can absorb it; balloon pericardiostomy; video-assisted thoracoscopic surgery; and pericardiectomy, removal of part of the sac. An indwelling catheter can also be left in for repeated drainage.

NCI is clear about the purpose of all of it. "The goal of treatment is usually palliative, to relieve symptoms and improve quality of life." Treating the underlying cancer may still be part of the plan, and the two run together.

• National Cancer Institute — Cardiopulmonary Syndromes (PDQ), Patient Version
• National Cancer Institute — Cardiopulmonary Syndromes (PDQ), Health Professional Version
• MedlinePlus — Cardiac tamponade
• MedlinePlus — Pericardiocentesis
• CDC — Watch Out for Fever (Preventing Infections in Cancer Patients)