Evaluation of respiratory chain failure in mitochondrial cardiomyopathy by assessments of 99mTc-MIBI washout and 123I-BMIPP/99mTc-MIBI mismatch

Mitochondrion. Feb-Apr 2007;7(1-2):164-70. doi: 10.1016/j.mito.2006.11.008. Epub 2006 Dec 5.

Abstract

Cardiomyopathy is one of the main features that determines prognosis in patients with mitochondrial encephalomyopathy. We investigated respiratory chain failure using 99mTc-MIBI- and 123I-BMIPP-SPECT in vivo in five patients with mitochondrial cardiomyopathty. With the lowering of cardiac function, the 99mTc-MIBI-washout rate (WOR) increased, and the 99mTc-MIBI-uptake decreased, conversely. In patients who showed severe cardiac involvement, 99mTc-MIBI-uptake was markedly reduced, and by contrast, 123I-BMIPP-uptake increased (123I-BMIPP/99mTc-MIBI mismatch). There were significant correlations between the WOR on 99mTc-MIBI-SPECT and interventricular septal thickness (IVST) on echocardiography and between WOR and left ventricular ejection fraction (LVEF) on 99mTc-MIBI-SPECT. The increased WOR and decreased uptake of 99mTc-MIBI were reflected by the lowered mitochondrial membrane potential created by mitochondrial respiratory chain whereas 123I-BMIPP/99mTc-MIBI mismatch may be created by the enhanced triglyceride-pool. These nuclear medicine techniques are the potential tools to evaluate the energy state in mitochondrial cardiomyopathy.

MeSH terms

  • Adolescent
  • Adult
  • Cardiomyopathies / diagnostic imaging*
  • Cardiomyopathies / physiopathology
  • Echocardiography
  • Electron Transport / physiology*
  • Fatty Acids*
  • Female
  • Humans
  • Iodine Radioisotopes
  • Iodobenzenes*
  • MELAS Syndrome / diagnostic imaging
  • MELAS Syndrome / physiopathology
  • Male
  • Middle Aged
  • Mitochondrial Encephalomyopathies / diagnostic imaging*
  • Mitochondrial Encephalomyopathies / physiopathology
  • Myocardium / metabolism
  • Technetium Tc 99m Sestamibi*
  • Tomography, Emission-Computed, Single-Photon

Substances

  • Fatty Acids
  • Iodine Radioisotopes
  • Iodobenzenes
  • iodofiltic acid
  • Technetium Tc 99m Sestamibi