Journal article
Acute hypoglycemia decreases myocardial blood flow reserve in patients with type 1 diabetes mellitus and in healthy humans
Circulation, Vol.124(14), pp.1548-1556
2011
Abstract
Background-: Hypoglycemia is associated with increased cardiovascular mortality, but the reason for this association is poorly understood. We tested the hypothesis that the myocardial blood flow reserve (MBFR) is decreased during hypoglycemia using myocardial contrast echocardiography in patients with type 1 diabetes mellitus (DM) and in healthy control subjects. Methods and Results-: Twenty-eight volunteers with DM and 19 control subjects underwent hyperinsulinemic clamps with maintained sequential hyperinsulinemic euglycemia (plasma glucose, 90 mg/dL [5.0 mmol/L]) followed by hyperinsulinemic hypoglycemia (plasma glucose, 50 mg/dL [2.8 mmol/L]) for 60 minutes each. Low-power real-time myocardial contrast echocardiography was performed with flash impulse imaging using low-dose dipyridamole stress at baseline and during hyperinsulinemic euglycemia and hyperinsulinemic hypoglycemia. In control subjects, MBFR increased during hyperinsulinemic euglycemia by 0.57 U (22%) above baseline (B coefficient, 0.57; 95% confidence interval, 0.38 to 0.75; P<0.0001) and decreased during hyperinsulinemic hypoglycemia by 0.36 U (14%) below baseline values (B coefficient,-0.36; 95% confidence interval,-0.50 to-0.23; P<0.0001). Although MBFR was lower in patients with DM at baseline by 0.37 U (14%; B coefficient,-0.37; 95% confidence interval,-0.55 to-0.19; P=0.0002) compared with control subjects at baseline, the subsequent changes in MBFR during hyperinsulinemic euglycemia and hyperinsulinemic hypoglycemia in DM patients were similar to that observed in control subjects. Finally, the presence of microvascular complications in the patients with DM was associated with a reduction in MBFR of 0.52 U (24%; B coefficient,-0.52; 95% confidence interval,-0.70 to-0.34; P<0.0001). Conclusions-: Hypoglycemia decreases MBFR in both healthy humans and patients with DM. This finding may explain the association between hypoglycemia and increased cardiovascular mortality in susceptible individuals. © 2011 American Heart Association. All rights reserved.
Details
- Title
- Acute hypoglycemia decreases myocardial blood flow reserve in patients with type 1 diabetes mellitus and in healthy humans
- Authors
- O Rana (Author) - Bournemouth University, United KingdomC D Byrne (Author) - University of Southampton, United KingdomDavid Kerr (Author) - Bournemouth University, United KingdomD V Coppini (Author) - Poole Hospital, United KingdomS Zouwail (Author) - Alexandria University, EgyptR Senior (Author) - Northwick Park Hospital, United KingdomJ Begley (Author) - Poole Hospital, United KingdomJ J Walker (Author) - University of Edinburgh, United KingdomKim Greaves (Author) - Bournemouth University, United Kingdom
- Publication details
- Circulation, Vol.124(14), pp.1548-1556
- Publisher
- Lippincott Williams & Wilkins
- DOI
- 10.1161/CIRCULATIONAHA.110.992297
- ISSN
- 0009-7322
- Organisation Unit
- Faculty of Science, Health, Education and Engineering; University of the Sunshine Coast, Queensland
- Language
- English
- Record Identifier
- 99449810602621
- Output Type
- Journal article