Summary

An 85-year-old man with a diagnosis of idiopathic dilated cardiomyopathy presented with worsening breathlessness and reduced functional capacity. Previous angiography had demonstrated only mild, single-vessel coronary atherosclerosis. Owing to the occurrence of severe symptoms despite optimal medical therapy, cardiac resynchronisation therapy (CRT) was performed by means of biventricular pacemaker implantation. The patient was readmitted, 6 months later, with an acute ST-segment myocardial infarction. Urgent coronary angiography demonstrated severe multivessel atherosclerotic coronary artery disease, in the absence of any alteration in basal drug therapy or modifiable cardiovascular risk factor profile. Percutaneous coronary intervention was performed with good result. We postulate a potential causal association between CRT and accelerated coronary atherosclerosis, with alterations in blood flow dynamics and coagulation properties as potential mechanisms. There are no previous reports of this phenomenon in the published literature.