As I write these words, I am alternating between my word processor and my browser, where I’m obsessively reading and re-reading the treatment and recurrence profile of pericarditis. I recently had a booster dose of an mRNA COVID-19 vaccine, and subsequently took my place among the very small cohort of people who have had a heart complication following vaccination. Two days after getting the jab, I began to experience chest pain, exacerbated by frivolous activities such as swallowing and lying down. After visiting a GP and yielding an abnormal result on the clinic’s electrocardiogram machine, I was told to go straight to the hospital. I drove, one hand on the wheel and the other on my chest, and somehow arrived at the emergency room for blood tests, an X-ray and the application of many cold electrodes on my skin. I stumbled away with a diagnosis of pericarditis and a prescription for three months’ worth of medication.

Pericarditis is, essentially, swelling of the tissue around the heart. A little sac-like house for a vital organ, the pericardium is there to protect the heart, keep it stable and separate it from other organs. It’s an excellent thing to have until it becomes inflamed, and then it’s a bit like your house is on fire—if that house was trapped behind layers of skin and bone and muscle, and you had very little agency in putting out the flames.