Effects of Hyperglycemia on Myocardial Perfusion in Humans With and Without Type 2 Diabetes

Overview

About this study

The overall goal of this proposal is to determine the effects of acute hyperglycemia and its modulation by Glucagon-like Peptide-1 (GLP-1) on myocardial perfusion in type 2 diabetes (DM). This study plan utilizes myocardial contrast echocardiography (MCE) to explore a) the effects of acute hyperglycemia on myocardial perfusion and coronary flow reserve in individuals with and without DM; and b) the effects of GLP-1 on myocardial perfusion and coronary flow reserve during euglycemia and hyperglycemia in DM. The investigators will recruit individuals with and without DM matched for age, gender and degree of obesity. The investigators will measure myocardial perfusion at rest and during vasodilator stress (to ascertain coronary flow reserve) while subjects are under controlled pancreatic clamp conditions during euglycemia (glucose ~100 mg/dl) and hyperglycemia (glucose ~250 mg/dl) in the presence and absence of concomitant GLP-1 infusion. The investigators believe that the translational significance of their studies is immense, impacting upon both acute and chronic cardiovascular disease manifestations. The effect of glycemic control on cardiovascular outcomes, morbidity and mortality remains an area of active investigation, fueled by the recent conflicting results of several large clinical trials (ACCORD, UKPDS, ADVANCE, VADT). If the investigators find that hyperglycemia is associated with altered myocardial perfusion, the mechanistic implications in the prevention and management of acute and chronic cardiovascular diseases in DM will be groundbreaking. Furthermore, if GLP-1 augments myocardial perfusion (as it does in the peripheral vasculature), the therapeutic benefits for prevention of cardiovascular events in this predisposed population are clear.

Participation eligibility

Participant eligibility includes age, gender, type and stage of disease, and previous treatments or health concerns. Guidelines differ from study to study, and identify who can or cannot participate. There is no guarantee that every individual who qualifies and wants to participate in a trial will be enrolled. Contact the study team to discuss study eligibility and potential participation.

Inclusion Criteria:

Males and females
Age 40-60 years
BMI ≤ 35 kg/m2
Diabetic subjects with HbA1c concentrations of ≤ 8%.
Diabetic subjects will be either on diet and lifestyle therapy alone, or monotherapy with metformin or sulphonylureas (except glyburide).
All diabetic subjects should be on stable dose oral agent therapy for 3 months prior to enrollment.

Exclusion Criteria:

Subjects with cerebrovascular or peripheral vascular disease.
Subjects with suspected or overt autonomic neuropathy.
Diabetic subject on thiazolidinediones, insulin, GLP-1 based therapies (exenatide or sitagliptin), alpha-glucosidase inhibitors, glyburide or combination antidiabetic drug therapies.
Diabetics with microalbuminuria.

Participating Mayo Clinic locations

Study statuses change often. Please contact the study team for the most up-to-date information regarding possible participation.

Mayo Clinic Location	Status
Rochester, Minn. Mayo Clinic principal investigator Sharon Mulvagh, M.D.	Closed for enrollment

Mayo Clinic Location

Status

Rochester, Minn.

Mayo Clinic principal investigator

Sharon Mulvagh, M.D.

Closed for enrollment

More information

Publications

Publications are currently not available

Clinical Trials