Delayed longitudinal myocardial function recovery after dobutamine challenge as a novel presentation of myocardial dysfunction in type 2 diabetic patients without angiographic coronary artery disease

AIMS: Since myocardial dysfunction in diabetic patients without coronary artery disease (CAD) is subtle at rest, the assessment during dobutamine stress echocardiography (DSE) may be more sensitive for detection of myocardial involvement. We assessed systolic function of the left ventricle during all stages of DSE in 3 diabetic patients free of significant CAD using state-of-the-art speckle-tracking quantification. METHODS AND RESULTS: We performed DSE in 250 patients with angina recording views during baseline (0), peak (1), and recovery phase (2). All patients had coronary anatomy verified with ≥ 50% stenosis in left main and ≥ 70% in other arteries considered as significant. In this analysis, we included 25 subjects with diabetes mellitus (DM) but without CAD (mean age 62 ± 8) and compared them with an age- and sex-matched group of 85 controls without DM and CAD (mean age 60 ± 9). Global peak systolic longitudinal strain (PSLS) of the left ventricle was obtained by automated function imaging (AFI) at rest, peak, and recovery phase of DSE. The global PSLS was similar in both groups at baseline (-17.3 ± 4.0% in diabetics vs. -18.7 ± 3.3% in controls, P = ns) and at peak stage of DSE (-16.4 ± 4.5% in diabetics vs. -17.9 ± 4.2% in controls, P = ns), whereas at recovery absolute value was lower in patients with DM (-15.3 ± 3.2% vs. -17.2 ± 3.3%, P = 0.01). CONCLUSION: Peak systolic longitudinal strain measured by AFI during recovery of DSE was impaired in diabetic patients. It may reflect longer time needed for full restoration of myocardial systolic function in this group of subjects.