What is pericarditis and how is it treated?

Pericarditis is inflammation of the pericardium, the thin, two-layered sac that surrounds your heart. When the pericardium becomes inflamed, the two layers rub against each other and produce a characteristic sharp chest pain, usually worse when you lie flat and noticeably better when you sit up and lean forward. The good news is that pericarditis is usually not dangerous and most patients make a full recovery within one to three weeks of starting treatment. Treatment is typically a course of anti-inflammatory medication, often combined with a second medication called colchicine to reduce the risk of the inflammation returning.

In my experience caring for patients across Kingston-upon-Thames and South West London, pericarditis is one of the more reassuring diagnoses I can give when chest pain turns out not to be a heart attack. That said, it does need to be properly assessed, properly distinguished from other causes of chest pain, and properly followed up to reduce the chance of recurrence. From working with the patients I see in clinic, I'd say roughly four out of every five cases settle completely with simple treatment and a short period of rest, with the remaining one in five needing closer monitoring for recurrent or persistent symptoms. Getting the diagnosis right early is what gives you the best chance of a smooth, full recovery.

What's Actually Happening Inside the Chest

Your heart sits inside a small sac called the pericardium. The pericardium has two thin layers with a tiny amount of fluid between them, which acts like a lubricant and lets the heart move smoothly as it beats. When the pericardium becomes inflamed, the two layers can rub together, and a small amount of extra fluid can collect between them. This is what produces the pain and the other typical symptoms.

Pericarditis can be acute (lasting less than three months and usually resolving within a few weeks of treatment), recurrent (returning after an initial recovery), or chronic (lasting longer than three months). The vast majority of patients I see have acute pericarditis, often triggered by a recent viral illness. Most of these recover fully, and many never have another episode.

The Symptoms to Look For

The classic symptom is chest pain, but it has a specific pattern that helps me distinguish pericarditis from other cardiac causes. The pain is usually sharp or stabbing rather than the pressure or tightness that's typical of angina. It tends to sit in the centre or left side of the chest, and it can spread to the shoulders, the neck, or the upper back.

What really points me towards pericarditis is the positional nature of the pain. It typically gets worse when you lie flat, breathe in deeply, cough or swallow, and it often eases significantly when you sit up and lean forward. From working with patients in clinic, that single feature, pain that improves when sitting forward, is one of the most reliable bedside clues we have.

Other symptoms can include:

• A low-grade fever

• A dry cough

• Fatigue or a general feeling of being unwell

• Mild breathlessness, particularly with exertion

• Palpitations or a fluttering sensation in the chest

  
  

Many patients describe a flu-like illness in the week or two before the chest pain starts, which fits with the most common underlying cause.

What Causes Pericarditis

In most cases of pericarditis I see, the underlying cause is a viral infection. Common cold viruses, flu, and other respiratory viruses can all trigger inflammation of the pericardium, usually a week or two after the original illness has resolved. In a significant proportion of cases, no specific cause is ever identified, and we label this as idiopathic pericarditis. In our experience, around half of the patients I see fall into this category.

Other causes I look out for include:

Bacterial infection. Rare in the UK, but a serious diagnosis when it does occur.

Autoimmune conditions. Lupus, rheumatoid arthritis and certain other inflammatory conditions can affect the pericardium.

Post-heart attack inflammation. Sometimes called Dressler's syndrome, this can develop weeks after a heart attack as the immune system reacts to damaged heart tissue.

After cardiac surgery. A similar inflammatory response can follow heart surgery or other cardiac procedures.

Kidney failure. Advanced kidney disease can cause a specific form known as uraemic pericarditis.

Cancer or its treatment. Some cancers, and certain chemotherapy or radiotherapy treatments, can affect the pericardium.

Trauma. A chest injury, even one that didn't seem serious at the time, can occasionally trigger pericarditis.

In my experience, identifying the underlying cause changes the treatment in a meaningful way in perhaps one in four cases. For most patients, especially those whose symptoms followed a viral illness, the focus is on treating the inflammation rather than chasing a specific trigger.

How Pericarditis Is Diagnosed

The diagnosis starts with a careful history. The positional chest pain pattern, combined with a recent viral illness, often points strongly towards pericarditis before any tests are done. A thorough examination follows, and one of the things I listen for is a pericardial rub, a scratchy or creaking sound caused by the inflamed layers of the pericardium rubbing together. When it's present, it's one of the more specific clinical signs in cardiology, although it isn't heard in every case.

The investigations I typically arrange include:

An ECG. Pericarditis often produces a characteristic pattern on the ECG, with widespread changes that are different from those seen in a heart attack. This is one of the most useful tests for confirming the diagnosis.

Blood tests. I look for raised inflammatory markers (CRP and ESR), a normal or modestly raised troponin (which helps distinguish pericarditis from a heart attack), and sometimes tests for autoimmune or infectious causes if the clinical picture suggests them.

An echocardiogram. This looks for a pericardial effusion, which is a build-up of fluid between the layers of the pericardium. Most effusions are small and don't need any specific treatment, but a few can become large enough to need drainage.

A cardiac MRI. I'll reserve this for cases where the diagnosis is unclear, where pericarditis keeps recurring, or where I'm concerned about more complex forms such as constrictive pericarditis. Cardiac MRI can show inflammation of the pericardium very clearly and is one of the most useful tools for the difficult cases.

In our experience, a focused assessment with a thorough history, an ECG and blood tests is enough to make a confident diagnosis in around eight out of ten cases. The remaining cases benefit from the additional imaging.

How Pericarditis Is Treated

Most patients with acute pericarditis are treated as outpatients with simple measures. The cornerstones of treatment are anti-inflammatory medication and rest.

Anti-inflammatory medication. Non-steroidal anti-inflammatory drugs, usually ibuprofen, are the first-line treatment. They reduce the inflammation in the pericardium and ease the pain, often within a few days. We'll usually prescribe a relatively high dose to start with and then taper it over a couple of weeks. Aspirin is preferred in patients who've recently had a heart attack. A stomach-protecting medication is often added because anti-inflammatories can irritate the stomach lining.

Colchicine. This is an older anti-inflammatory medication that has become a really important addition to pericarditis treatment over the past decade. Added to ibuprofen for around three months, colchicine has been shown to roughly halve the rate of recurrence. In my experience, colchicine works better than anti-inflammatories alone because it not only helps the current episode settle faster but actively reduces the chance of the condition coming back. It's one of the clearest examples in cardiology of a simple medication making a substantial difference to long-term outcomes.

Rest. Strenuous exercise should be avoided until the symptoms have settled and the inflammatory markers in the blood have returned to normal. I'd typically advise patients to step back from competitive sport, gym workouts or running until I'm satisfied the inflammation has resolved. Gentle walking and normal daily activities are usually fine.

Treating the underlying cause. If a specific cause has been identified, such as a bacterial infection or an autoimmune condition, treating that directly is essential.

Steroids. Corticosteroids are usually held in reserve for patients who don't respond to ibuprofen and colchicine. I use them cautiously because, in some patients, they can actually increase the risk of recurrence.

Drainage of a large effusion. If the echocardiogram shows a large pericardial effusion that's affecting how the heart fills with blood, a procedure called pericardiocentesis may be needed. This is reserved for a small minority of cases.

Most patients feel significantly better within a week of starting treatment and make a full recovery within one to three weeks. The full course of colchicine continues for three months even after symptoms have settled, because that's what gives the best protection against recurrence.

Recurrence and Long-Term Outlook

The honest reality is that pericarditis can come back. Recurrence happens in around 15 to 30 per cent of patients within the first 18 months, even with appropriate initial treatment. This isn't a sign that the original diagnosis was wrong or that the treatment failed. It reflects the underlying biology of how the pericardium responds to inflammation.

In my experience, the patients who do best with recurrent pericarditis are those who:

• Complete a full course of colchicine, even when they feel well

• Avoid stopping anti-inflammatories too early

• Build back to exercise gradually rather than rushing back to competitive activity

• Have a clear follow-up plan with a cardiologist who can adjust treatment if symptoms return

  
  

For the small number of patients who develop multiple recurrences or chronic symptoms, specialist input becomes essential. Longer-term colchicine, immunomodulatory medications, and occasionally cardiac surgery for the very rare cases of constrictive pericarditis are all options.

The much rarer but more serious complications, cardiac tamponade (where a large effusion compresses the heart) and constrictive pericarditis (chronic scarring of the pericardium leading to heart failure), are uncommon but worth knowing about. Both are reasons I'd want any patient with pericarditis to have proper imaging and at least one cardiology review before being discharged from follow-up.

When to Seek Urgent Help

Any sudden, severe chest pain warrants urgent assessment. If your pain is severe and lasting more than 15 minutes, doesn't ease with sitting forward, comes with sweating, breathlessness, or a feeling of impending doom, call 999. This may be a heart attack, and time genuinely matters.

If you've been diagnosed with pericarditis and your symptoms get worse, your breathlessness increases significantly, your ankles start to swell, or you become aware of new palpitations, you should be seen the same day. These can occasionally be signs of a developing effusion or another complication, and they deserve to be checked promptly.

For ongoing or recurrent chest pain that fits the pericarditis pattern, a proper cardiology assessment is the right next step, particularly if previous episodes have been managed without a clear diagnosis or follow-up plan.

Conclusion

Pericarditis sounds frightening, but for the vast majority of patients it's a self-limiting inflammatory condition that responds well to straightforward treatment. The key is getting the diagnosis right early, ruling out the things it can mimic, starting the right combination of anti-inflammatory medication and colchicine, and making sure there's a sensible follow-up plan to reduce the risk of recurrence. With those pieces in place, most patients are back to full normal activity within a few weeks and stay well long term.

If you've recently been diagnosed with pericarditis, are experiencing chest pain that fits this pattern, or have had recurrent episodes that aren't fully resolving, you can contact me, Dr Roy Jogiya, at Kingston Cardiologists to arrange a private consultation across Kingston-upon-Thames, Wimbledon, or central London. Appointments are available in person and virtually, with full diagnostic support including same-day ECG, echocardiography, and onward cardiac MRI if needed.