In this case, the Sweet's syndrome (SS) developed secondary to acute myeloid leukaemia (AML). In AML, the heart muscle can be infiltrated by malignant leukaemia cells, but SS can also cause heart problems, including myocarditis (inflammation of the heart muscle).
"Acute myeloid leukemia has a highly variable clinical presentation with rare associations documented. AML-related myocarditis is one such poorly studied disease entity. In general, myocarditis is a disease secondary to inflammation of the cardiac muscle and has a nonspecific clinical presentation that ranges from acute chest pain to new onset heart failure to cardiogenic shock, among others."
"Infiltration of the heart muscle by malignant leukemia cells is a known sequela of AML, but this process is usually subclinical for unknown reasons."
"This patient's concurrent myocarditis diagnosis was established with cardiac MRI using the updated Lake Louise criteria. His myocarditis was likely related to his diagnosis of sweet syndrome due to exclusion of other etiologies and occurring in the setting of both sweet syndrome rash and acute leukemia, two known associations." ncbi.nlm.nih.gov/pmc/articl...
ADDITIONAL NOTES:
Extracutaneous manifestations of Sweet's syndrome, 2007.
Heart: "Aortic stenosis (segmental), aortitis (neutrophilic and segmental), cardiomegaly, coronary artery occlusion, heart failure, myocardial infiltration by neutrophils, vascular (aorta, bracheocephalic trunk and coronary arteries) dilatation." ojrd.biomedcentral.com/arti...?