Analysis of midwall shortening reveals high prevalence of left ventricular myocardial dysfunction in patients with diabetes mellitus: the DYDA study

BACKGROUND: Individuals with diabetes mellitus (DM) have a higher risk to develop heart failure. Clinical guidelines emphasize the importance of early diagnosis of left ventricular dysfunction (LVD) and preventive interventions in these patients. In this study we assessed the prevalence of LVD, systolic or diastolic, in DM patients without known cardiac disease recruited in the 'left ventricular DYsfunction in DiAbetes (DYDA)' study. DESIGN AND METHODS: We performed clinical, ECG, laboratory, and echocardiographic exams in 960 patients (61 ± 8 years, 59% hypertensive) recruited in the DYDA study from 37 Italian diabetes referral centres. ECG and echo exams were read in central facilities. Systolic LVD was defined as ejection fraction ≤ 50% or midwall shortening (MFS) ≤ 15%. Diastolic LVD was identified when transmitral E/A was out of the range of 0.75-1.5 or deceleration time of mitral E wave ≤ 140 msec. RESULTS: Echocardiographic data were obtained in 751 patients (78.2%). Isolated systolic LVD was detected in 22.0% of patients, isolated diastolic LVD in 21.5%, and combined systolic and diastolic LVD in 12.7%. All patients with systolic LVD had MFS ≤ 15%, while only 9% had an ejection fraction ≤ 50%. Higher LV mass, relative wall thickness, prevalence of concentric geometry, and LV hypertrophy characterized the patients with LVD. CONCLUSIONS: LVD is present in more than half of DM patients without clinically detectable cardiac disease and is associated with LV hypertrophy and concentric LV geometry. One-third of patients exhibits systolic LVD detectable at the midwall level.