We sought to determine whether disturbances of myocardial contractility and reflectivity could be detected in diabetic patients without overt heart disease and whether these changes were independent and incremental to left ventricular hypertrophy (LVH).
Background
Left ventricular (LV) dysfunction is associated with diabetes mellitus, but LVH is common in this population and the relationship between diabetic LV dysfunction and LVH is unclear.
Methods
We studied 186 patients with normal ejection fraction and no evidence of CAD: 48 with diabetes mellitus only (DM group), 45 with LVH only (LVH group), 45 with both diabetes and LVH (DH group), and 48 normal controls. Peak strain and strain rate of six walls in apical four-chamber, long-axis, and two-chamber views were evaluated and averaged for each patient. Calibrated integrated backscatter (IB) was assessed by comparison of the septal or posterior wall with pericardial IB intensity.
Results
All patient groups (DM, DH, LVH) showed reduced systolic function compared with controls, evidenced by lower peak strain (p < 0.001) and strain rate (p = 0.005). Calibrated IB, signifying myocardial reflectivity, was greater in each patient group than in controls (p < 0.05). Peak strain and strain rate were significantly lower in the DH group than in those in the DM alone (p < 0.03) or LVH alone (p = 0.01) groups.
Conclusions
Diabetic patients without overt heart disease demonstrate evidence of systolic dysfunction and increased myocardial reflectivity. Although these changes are similar to those caused by LVH, they are independent and incremental to the effects of LVH.
Abbreviations
Am
peak myocardial late diastolic velocity
ANOVA
analysis of variance
CAD
coronary artery disease
DH group
diabetic patients with left ventricular hypertrophy
DM group
diabetic patients without left ventricular hypertrophy
Em
peak myocardial early diastolic velocity
HbA1c
hemoglobin A1c
IB
integrated backscatter
LV
left ventricular
LVH
left ventricular hypertrophy
LVH group
nondiabetic patients with left ventricular hypertrophy