Abstract 13272: Diabetic Cardiomyopathy as a Coronary Artery Disease Mimic: A Case Report

Abstract

A 49-year-old female presented with complaints of angina and dyspnea on exertion for last 4 months, which caused significant limitation of ordinary physical activity. She had poorly controlled diabetes mellitus type 2 with HbA1C of 10.3%. EKG showed complete LBBB with QRS duration of 180 milliseconds. Echocardiogram was consistent with dilated left ventricle and global hypokinesia of left ventricle with ejection fraction of 25-30%. There was marked reduction in GLS (GLPS average of -7.0%). She underwent coronary angiogram which revealed normal epicardial coronary arteries. 99m Tc-sestamibi SPECT myocardial perfusion imaging (MPI) at rest, demonstrated moderate to severe ischemia involving apical, antero-septal, adjacent anterior wall and adjacent basal 2/3 rd of inferior wall segments of LV myocardium (involving approx.~73% of RCA territory and 57% of LAD territory at 50% uptake threshold). There was wall motion abnormality in above mentioned segments on ECG gated SPECT and estimated LVEF with QGS was ~29±5%. She has been started on anti-ischemic measures, guideline directed therapy for HFrEF and comprehensive diabetes care. Diabetic cardiomyopathy is myocardial dysfunction with normal epicardial coronary arteries and absence of other cardiovascular diseases. It is characterized by myocardial fibrosis and associated systolic dysfunction preceded by diastolic dysfunction. Cardiac insulin resistance leads to advanced glycation end products, microvascular dysfunction etc. Perfusion defects observed during MPI in patients with LBBB may be due to CAD, microvascular dysfunction, or artifacts. In the setting of LBBB, isolated anteroseptal defect has low probability of CAD but presence of perfusion defects in RCA territory and apical region increases probability of ischemic events.In this case, there was ischemia with systolic dysfunction in the absence of any overt clinical coronary artery disease and no other identifiable cause.