Acute hypoglycemia decreases myocardial blood flow reserve in patients with type 1 diabetes mellitus and in healthy humans

Authors: Rana, O., Byrne, C.D., Kerr, D., Coppini, D.V., Zouwail, S., Senior, R., Begley, J., Walker, J.J. and Greaves, K.

Journal: Circulation

Volume: 124

Issue: 14

Pages: 1548-1556

eISSN: 1524-4539

ISSN: 0009-7322

DOI: 10.1161/CIRCULATIONAHA.110.992297

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.

Source: Scopus

Preferred by: David Kerr

Acute hypoglycemia decreases myocardial blood flow reserve in patients with type 1 diabetes mellitus and in healthy humans.

Authors: Rana, O., Byrne, C.D., Kerr, D., Coppini, D.V., Zouwail, S., Senior, R., Begley, J., Walker, J.J. and Greaves, K.

Journal: Circulation

Volume: 124

Issue: 14

Pages: 1548-1556

eISSN: 1524-4539

DOI: 10.1161/CIRCULATIONAHA.110.992297

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.

Source: PubMed

Acute Hypoglycemia Decreases Myocardial Blood Flow Reserve in Patients With Type 1 Diabetes Mellitus and in Healthy Humans

Authors: Rana, O., Byrne, C.D., Kerr, D., Coppini, D.V., Zouwail, S., Senior, R., Begley, J., Walker, J.J. and Greaves, K.

Journal: CIRCULATION

Volume: 124

Issue: 14

Pages: 1548-U146

ISSN: 0009-7322

DOI: 10.1161/CIRCULATIONAHA.110.992297

Source: Web of Science (Lite)

Acute hypoglycemia decreases myocardial blood flow reserve in patients with type 1 diabetes mellitus and in healthy humans.

Authors: Rana, O., Byrne, C.D., Kerr, D., Coppini, D.V., Zouwail, S., Senior, R., Begley, J., Walker, J.J. and Greaves, K.

Journal: Circulation

Volume: 124

Issue: 14

Pages: 1548-1556

eISSN: 1524-4539

ISSN: 0009-7322

DOI: 10.1161/circulationaha.110.992297

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.

Source: Europe PubMed Central