Effect of nitroglycerin on splanchnic and pulmonary blood volume

J Nucl Cardiol. 2022 Dec;29(6):2952-2963. doi: 10.1007/s12350-021-02811-7. Epub 2021 Nov 2.


Background: Sublingual nitroglycerin (SL NTG) is useful for treating acute decompensated heart failure, possibly by increasing splanchnic capacitance and reducing left ventricular (LV) preload. We evaluated a radionuclide method to study these effects, initially in subjects without heart failure.

Methods and results: Red blood cells were labelled by an in vitro method. Abdominal and chest images were obtained at rest, showing relative regional blood volumes. The abdomen was then re-imaged during progressive escalation of intrathoracic pressure using continuous positive airway pressure to assess baseline splanchnic capacitance (pressure-volume relationship, PVR) and compliance (slope of PVR). The procedure was repeated after 0.6 mg SL NTG, followed by chest images. Relative splanchnic blood volume increased at rest after SL NTG (P < .002), signifying an increase in splanchnic capacitance. The slope of the splanchnic PVR decreased in proportion to the baseline PVR (P = .0014), signifying increased compliance. The relative pulmonary blood volume decreased in proportion to the increase in splanchnic blood volume (P = .01).

Conclusions: A semi-quantitative radionuclide method demonstrated the effect of SL NTG for increasing splanchnic capacitance and compliance, with a proportional decrease in pulmonary blood volume. These data may be applied to quantitatively evaluate the importance of splanchnic vasodilation as a mechanism of LV preload reduction in the treatment of heart failure.

Clinical trials registration: NCT02425566.

Keywords: Splanchnic scintigraphy; heart failure; radionuclide imaging; splanchnic pressure-volume relations.

Publication types

  • Clinical Trial
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Blood Pressure
  • Blood Volume
  • Heart Failure* / diagnostic imaging
  • Heart Failure* / drug therapy
  • Humans
  • Lung
  • Nitroglycerin* / pharmacology
  • Radioisotopes / pharmacology


  • Nitroglycerin
  • Radioisotopes

Associated data

  • ClinicalTrials.gov/NCT02425566