Dataset Information

SPECT/CT imaging of lower extremity perfusion reserve: A non-invasive correlate to exercise tolerance and cardiovascular fitness in patients undergoing clinically indicated myocardial perfusion imaging.

ABSTRACT:

Background

Although exercise is often prescribed for the management of cardiovascular diseases, a non-invasive imaging approach that quantifies skeletal muscle physiology and correlates with patients' functional capacity and cardiovascular fitness has been absent. Therefore, we evaluated the potential of lower extremity single photon emission computed tomography (SPECT)/CT perfusion imaging as a non-invasive correlate to exercise tolerance and cardiovascular fitness.

Methods

Patients (n?=?31) undergoing SPECT/CT myocardial perfusion imaging underwent additional stress/rest SPECT/CT imaging of the lower extremities. CT-based image segmentation was used for regional quantification of perfusion reserve within the tibialis anterior, soleus, and gastrocnemius muscles. Metabolic equivalents (METs) at peak exercise and heart rate recovery (HRR) after exercise were recorded.

Results

Peak METs were significantly associated with perfusion reserve of tibialis anterior (p?=?0.02), soleus (p?=?0.01) and gastrocnemius (p?=?0.01). HRR was significantly associated with perfusion reserve of the soleus (p?=?0.02) and gastrocnemius (p?=?0.04) muscles. Perfusion reserve of the tibialis anterior (40.6?±?20.2%), soleus (35.4?±?16.7%), and gastrocnemius (29.7?±?19.1%) all significantly differed from each other.

Conclusions

SPECT/CT imaging provides regional quantification of skeletal muscle perfusion reserve which is significantly associated with exercise tolerance and cardiovascular fitness. Future application of SPECT/CT may elucidate the underlying skeletal muscle adapations to exercise therapy in patients with cardiovascular diseases.

SUBMITTER: Chou TH

PROVIDER: S-EPMC7749094 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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Publications

SPECT/CT imaging of lower extremity perfusion reserve: A non-invasive correlate to exercise tolerance and cardiovascular fitness in patients undergoing clinically indicated myocardial perfusion imaging.

Chou Ting-Heng TH Janse Sarah S Sinusas Albert J AJ Stacy Mitchel R MR

Journal of nuclear cardiology : official publication of the American Society of Nuclear Cardiology 20200114 6

<h4>Background</h4>Although exercise is often prescribed for the management of cardiovascular diseases, a non-invasive imaging approach that quantifies skeletal muscle physiology and correlates with patients' functional capacity and cardiovascular fitness has been absent. Therefore, we evaluated the potential of lower extremity single photon emission computed tomography (SPECT)/CT perfusion imaging as a non-invasive correlate to exercise tolerance and cardiovascular fitness.<h4>Methods</h4>Patie ...[more]

PMID: 31939039

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Dataset Information

SPECT/CT imaging of lower extremity perfusion reserve: A non-invasive correlate to exercise tolerance and cardiovascular fitness in patients undergoing clinically indicated myocardial perfusion imaging.

Background

Methods

Results

Conclusions

Publications

SPECT/CT imaging of lower extremity perfusion reserve: A non-invasive correlate to exercise tolerance and cardiovascular fitness in patients undergoing clinically indicated myocardial perfusion imaging.

Similar Datasets

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