Effect of glycaemic control on myocardial sympathetic innervation assessed by [123I]metaiodobenzylguanidine scintigraphy: a 4-year prospective study in IDDM patients

Diabetologia. 1998 Apr;41(4):443-51. doi: 10.1007/s001250050928.

Abstract

Diabetic cardiovascular autonomic neuropathy (CAN) has been directly characterized by reduced or absent myocardial [123I]metaiodobenzylguanidine (MIBG) uptake, but there is no information available on the relationship between the myocardial adrenergic innervation defects and long-term glycaemic control. In a prospective study over a mean of 4 years we examined myocardial sympathetic innervation in 12 Type 1 (insulin-dependent) diabetic patients using MIBG scintigraphy (absolute and relative global MIBG uptake at 2 h p.i.) in conjunction with cardiovascular autonomic function tests, QTc interval, and QT dispersion. Six healthy non-diabetic subjects served as controls for the MIBG scintigraphy at baseline. HbA1c was measured twice a year. One patient, in whom MIBG accumulation was reduced maximally, died during follow up. Among the remaining patients 5 had good or borderline glycaemic control (mean HbA1c < 7.6%; Group 1), whereas 6 patients were poorly controlled (mean HbA1c > or = 7.6%; Group 2). Absolute global MIBG uptake increased from baseline to follow-up by 260 (-190-540) [median (range)] cpm/g in Group 1 and decreased by -150 (-450-224) cpm/g in Group 2 (p < 0.05 vs Group 1). Relative global MIBG uptake decreased by -1.7 (-3.4-9.4) % in Group 1 and by -4.7 (-17.4-1.3) % in Group 2 (p < 0.05 vs Group 1). No differences between the groups were noted for the changes in the automatic function tests, QTc interval, and QT dispersion. In conclusion, long-term poor glycaemic control constitutes an essential determinant in the progression of left ventricular adrenergic dysinnervation which may be prevented by near-normoglycaemia. Evaluation of susceptibility to metabolic intervention may be superior when CAN is characterized directly by MIBG scintigraphy rather than by indirect autonomic function testing.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3-Iodobenzylguanidine* / pharmacokinetics
  • Adult
  • Aged
  • Biomarkers / blood
  • Blood Glucose / metabolism*
  • Blood Pressure
  • Diabetes Mellitus, Type 1 / diagnostic imaging
  • Diabetes Mellitus, Type 1 / metabolism
  • Diabetes Mellitus, Type 1 / physiopathology*
  • Diabetic Neuropathies / physiopathology
  • Diabetic Retinopathy / physiopathology
  • Electrocardiography
  • Female
  • Glycated Hemoglobin A / analysis*
  • Heart / diagnostic imaging
  • Heart / innervation*
  • Heart Rate
  • Humans
  • Long QT Syndrome
  • Male
  • Middle Aged
  • Peripheral Nerves / physiopathology
  • Radionuclide Imaging
  • Radiopharmaceuticals* / pharmacokinetics
  • Reference Values
  • Sympathetic Nervous System
  • Ventricular Function, Left

Substances

  • Biomarkers
  • Blood Glucose
  • Glycated Hemoglobin A
  • Radiopharmaceuticals
  • 3-Iodobenzylguanidine