Evaluation of DNA damage induced by ionizing radiation from myocardial perfusion imaging: a pilot study

BMC Cardiovasc Disord. 2022 Sep 3;22(1):394. doi: 10.1186/s12872-022-02839-8.


Background: As patient exposure to ionizing radiation raises concern about malignancy risks, this study evaluated the effect of ionizing radiation on patients undergoing myocardial perfusion imaging (MPI) using the comet assay, a method for detection of DNA damage.

Methods: Patients without cancer, acute or autoimmune diseases, recent surgery or trauma, were studied. Gated single-photon myocardial perfusion imaging was performed with Tc-99m sestamibi. Peripheral blood was collected before radiotracer injection at rest and 60-90 min after injection. Single-cell gel electrophoresis (comet assay) was performed with blood lymphocytes to detect strand breaks, which determine a "comet tail" of variable size, visually scored by 3 observers in a fluorescence microscope after staining (0: no damage, no tail; 1: small damage; 2: large damage; 3: full damage). A damage index was calculated as a weighted average of the cell scores.

Results: Among the 29 individuals included in the analysis, age was 65.3 ± 9.9 years and 18 (62.1%) were male. The injected radiotracer dose was 880.6 ± 229.4 MBq. Most cells (approximately 70%) remained without DNA fragmentation (class 0) after tracer injection. There were nonsignificant increases of classes 1 and 2 of damage. Class 3 was the least frequent both before and after radiotracer injection, but displayed a significant, 44% increase after injection.

Conclusion: While lymphocytes mostly remained in class 0, an increase in class 3 DNA damage was detected. This may suggest that, despite a probable lack of biologically relevant DNA damage, there is still a need for tracer dose reductions in MPI.

Keywords: Comet assay; DNA; Myocardial perfusion imaging; Radiation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • DNA Damage
  • Female
  • Humans
  • Male
  • Middle Aged
  • Myocardial Perfusion Imaging* / methods
  • Perfusion
  • Pilot Projects
  • Radiation, Ionizing
  • Technetium Tc 99m Sestamibi*


  • Technetium Tc 99m Sestamibi