Myocardial structure, function, and scar in patients with type 1 diabetes mellitus

Abstract

Background: We report relationships between cardiovascular disease risk factors and myocardial structure, function, and scar in patients with type 1 diabetes mellitus in the Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications (DCCT/EDIC) study.

Methods and results: Cardiac magnetic resonance was obtained in 1017 patients with type 1 diabetes mellitus. Gadolinium cardiac magnetic resonance was also obtained in 741 patients. The mean age was 49±7 years; 52% were men; and mean duration of diabetes mellitus was 28±5 years. Associations of cardiovascular disease risk factors with cardiac magnetic resonance parameters were examined with linear and logistic regression models. History of macroalbuminuria was positively associated with left ventricular mass (by 14.8 g), leading to a significantly higher ratio of left ventricular mass to end-diastolic volume (by 8%). Mean hemoglobin A(1c) levels over the preceding 22 years were inversely associated with end-diastolic volume (-3.0 mL per unit mean hemoglobin A(1c) percent) and stroke volume (-2.3 mL per unit mean hemoglobin A(1c) percent) and positively related to the ratio of elevated left ventricular mass to end-diastolic volume (0.02 g/mL per unit). The overall prevalence of myocardial scar was 4.3% by cardiac magnetic resonance and 1.4% by clinical adjudication of myocardial infarction. Both mean hemoglobin A(1c) (odds ratio, 1.5 [95% confidence interval, 1.0-2.2] per unit) and macroalbuminuria (odds ratio, 3.5 [95% confidence interval, 1.2-9.9]) were significantly associated with myocardial scar and traditional cardiovascular disease risk factors.

Conclusions: In addition to traditional cardiovascular disease risk factors, elevated mean hemoglobin A(1c) and macroalbuminuria were significantly associated with alterations in left ventricular structure and function. The prevalence of myocardial scar was 4.3% in this subcohort of DCCT/EDIC participants with relatively preserved renal function. Clinical Trial Registration-URL: http://www.clinicaltrials.gov. Unique identifiers: NCT00360893 and NCT00360815.

Figures

Figure 1

Flow Chart of DCCT/EDIC Participants in the EDIC CMR study: At the time of CMR exam, 1,301 patients were being followed in the main EDIC study. The mean follow-up was 22 years during entire DCCT/EDIC (or 15 years for EDIC). CMR was available for 1,259 patients at imaging centers near the EDIC clinic. Of these, 1,017/1,259 (81%) underwent CMR between 14th and 16th follow-up years of EDIC. 755 had delayed enhancement CMR.

Figure 2

A) Ischemic myocardial scar. Inversion recovery segmented spoiled gradient recalled echo short CMR shows transmural enhancement of the myocardial wall (arrow) in a participant with a clinically adjudicated myocardial infarction. B) Non ischemic myocardial scar. Delayed enhancement short axis CMR demonstrates a linear myocardial scar in the left ventricular septum (arrow). The study participant had no history of silent MI or adjudicated MI.

Figure 2

A) Ischemic myocardial scar. Inversion recovery segmented spoiled gradient recalled echo short CMR shows transmural enhancement of the myocardial wall (arrow) in a participant with a clinically adjudicated myocardial infarction. B) Non ischemic myocardial scar. Delayed enhancement short axis CMR demonstrates a linear myocardial scar in the left ventricular septum (arrow). The study participant had no history of silent MI or adjudicated MI.