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Updated: Aug 23, 2026

In Vivo Quantitative Assessment of Myocardial Structure, Function, Perfusion and Viability Using Cardiac Micro-computed Tomography
08:13

In Vivo Quantitative Assessment of Myocardial Structure, Function, Perfusion and Viability Using Cardiac Micro-computed Tomography

Published on: February 16, 2016

Sympathetic nervous function in patients with hypertrophic cardiomyopathy assessed by [123I]-MIBG: relationship with

L Pace1, S Betocchi, M A Losi

  • 1Department of Biomorphologic and Functional Sciences, Federico II University, Naples, Italy. pace@unina.it

The Quarterly Journal of Nuclear Medicine and Molecular Imaging : Official Publication of the Italian Association of Nuclear Medicine (AIMN) [And] the International Association of Radiopharmacology (IAR), [And] Section of the Society Of
|June 15, 2004
PubMed

Insights

Cardiac sympathetic activity, measured by [123I] MIBG clearance, correlates with cardiac anatomy and diastolic function in hypertrophic cardiomyopathy (HCM) patients. Higher MIBG washout rates indicate increased sympathetic activity linked to greater hypertrophy and impaired diastolic function.

Area of Science:

  • Nuclear cardiology
  • Cardiovascular imaging
  • Cardiac pathophysiology

Background:

  • Hypertrophic cardiomyopathy (HCM) is a complex cardiac disease characterized by left ventricular hypertrophy.
  • Assessing cardiac sympathetic nerve function is crucial for understanding HCM progression and outcomes.
  • Iodine-123 meta-iodobenzylguanidine ([123I] MIBG) scintigraphy is a valuable tool for evaluating cardiac sympathetic innervation.

Purpose of the Study:

  • To evaluate [123I] MIBG uptake and clearance in patients with HCM.
  • To assess the relationship between [123I] MIBG parameters and left ventricular systolic and diastolic function.
  • To correlate [123I] MIBG findings with cardiac perfusion and anatomy in HCM.

Main Methods:

  • Eleven HCM patients underwent [123I] MIBG scintigraphy and echocardiography.
  • [123I] MIBG scintigraphy included planar and SPECT imaging at 5 minutes and 4 hours post-injection.
  • Washout rate (WOR) and heart-to-mediastinum ratio (H/M) were calculated. Echocardiography assessed left ventricular function, outflow tract gradient (LVOTG), and septal thickness.

Main Results:

  • [123I] MIBG WOR positively correlated with LVOTG (r=0.84) and septum thickness (r=0.76).
  • A negative correlation was observed between WOR and left atrial fractional shortening (LAFS) (r=-0.66).
  • Patients with higher WOR exhibited lower LAFS, higher LVOTG, and thicker septa compared to those with lower WOR.

Conclusions:

  • Cardiac sympathetic activity, as indicated by [123I] MIBG WOR, is closely related to cardiac anatomy in HCM.
  • Diastolic function, assessed by LAFS, is also significantly associated with cardiac sympathetic activity in HCM patients.
  • [123I] MIBG scintigraphy provides valuable insights into the interplay between sympathetic innervation, cardiac structure, and function in HCM.
Abstract

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