An international team of Belgian and American researchers has uncovered a significant connection between mutated blood cells and an increased risk of myocarditis and pericarditis, which are inflammations of the heart muscle and the heart’s surrounding sac.
The study found that a process called clonal haematopoiesis of indeterminate potential (CHIP), characterised by an accumulation of mutated blood cells, raises the likelihood of developing these heart inflammations by approximately 75%.
The findings are based on an analysis of over 335,000 adults from the UK Biobank, a large-scale health study conducted in the United Kingdom over nearly 14 years. During the study, 382 participants were diagnosed with myocarditis or pericarditis.
Myocarditis and pericarditis are rare but potentially severe conditions, affecting an estimated 5 to 10 in every 100,000 adults each year. They can lead to heart failure or life-threatening arrhythmias, often with no clear cause. Limited knowledge about the mechanisms driving these diseases has meant fewer options for prevention and treatment.
CHIP occurs when certain white blood cells, responsible for managing inflammatory responses, undergo genetic mutations and begin to proliferate uncontrollably. This phenomenon is more common among older adults, with 10% to 20% of individuals aged 70 and above having CHIP without knowing it.
While previous research linked CHIP to heart rhythm disorders, the new study highlights a much stronger connection to myocarditis and pericarditis. Researchers believe this discovery may help explain some earlier findings related to CHIP and heart conditions.
“The link between CHIP and heart inflammation is far stronger than with other heart diseases previously associated with CHIP,” said Art Schuermans, a medical student at KU Leuven who collaborated with researchers from Harvard Medical School and the Broad Institute of MIT and Harvard.
“Since CHIP originates in white blood cells—the cells regulating inflammatory responses—we think these cells directly contribute to inflammation of the heart tissue and its surrounding sac. This opens new avenues for treatment, such as using targeted anti-inflammatory drugs,” Schuermans added.
The findings were presented by Schuermans on 30 August at the annual congress of the European Society of Cardiology (ESC) in Madrid. The study has also been published in *JAMA Cardiology*, a leading international journal in cardiovascular research.
