Prototype device for endoventricular beta-emitting radiotracer detection and molecularly-guided intervention

• Published in: Journal of nuclear cardiology 2022-04, Vol.29 (2), p.663-676
• Main Authors: Stendahl, John C., Liu, Zhao, Boutagy, Nabil E., Nataneli, Eliahoo, Daghighian, Farhad, Sinusas, Albert J.
• Format: Article
• Language: English
• Subjects: Animals; Cardiology; Catheters; Fluorodeoxyglucose F18; Heart; Humans; Image guided application; Imaging; instrumentation; Medicine; Medicine & Public Health; molecular imaging; Myocardial Infarction - diagnostic imaging; myocardial ischemia and infarction; Myocardium; Nuclear Medicine; Original Article; PET; Positron Emission Tomography Computed Tomography; Positron-Emission Tomography - methods; Radiation; Radiology; Swine
• ISSN: 1071-3581; 1532-6551
• DOI: 10.1007/s12350-020-02317-8

We have set out to develop a catheter-based theranostic system that: (a) identifies diseased and at-risk myocardium via endocardial detection of systemically delivered β-emitting radiotracers and (b) utilizes molecular signals to guide delivery of therapeutics to appropriate tissue via direct intramyocardial injection. Our prototype device consists of a miniature β-radiation detector contained within the tip of a flexible intravascular catheter. The catheter can be adapted to incorporate an injection port and retractable needle for therapeutic delivery. The performance of the β-detection catheter was assessed in vitro with various β-emitting radionuclides and ex vivo in hearts of pigs following systemic injection of 18F-fluorodeoxyglucose (18F-FDG) at 1-week post-myocardial infarction. Regional catheter-based endocardial measurements of 18F activity were compared to regional tissue activity from PET/CT images and gamma counting. The β-detection catheter demonstrated sensitive in vitro detection of β-radiation from 22Na (β+), 18F (β+), and 204Tl (β-), with minimal sensitivity to γ-radiation. For 18F, the catheter demonstrated a sensitivity of 4067 counts/s/μCi in contact and a spatial resolution of 1.1 mm FWHM. Ex vivo measurements of endocardial 18F activity with the β-detection catheter in the chronic pig infarct model demonstrated good qualitative and quantitative correlation with regional tissue activity from PET/CT images and gamma counting. The prototype β-detection catheter demonstrates sensitive and selective detection of β- and β+ emissions over a wide range of energies and enables high-fidelity ex vivo characterization of endocardial activity from systemically delivered 18F-FDG.