Frank Bengel - Baltimore US - reported on the latest developments with the availability of PET to monitor and evaluate the treatment with gene and cell therapy. PET-CT provides both precise anatomical and functional information and seems like a promising modality. The development of gene therapy is critically dependent on modalities enabling precise monitoring of the effects. PET enables labelling of both the vector and the effect of therapy, particularly reporter gene imaging, seems like a workable model. No human studies are available yet due to unresolved technical and ethical issues, but the technique is clearly promising. Proof of principle has been published, but only a few groups work with the technique and a close collaboration between these groups and with the clinical and experimental projects evaluating the therapy would seem like a valuable initiative.
Heinz Schelbert - Los Angeles, US - provided an overview of the present knowledge about regulation of myocardial perfusion and perfusion reserve and the ability of PET to assess these parameters. The technique, including tracers and kinetic models, was discussed and the present knowledge on possibilities and problems clearly elucidated. Newer data providing also prognostic information were discussed and the potential to monitor endothelial function and evaluate risk factor modification were debated.
Philip Kaufmann – Zurich CH - discussed the capability of PET to image cardiac innervation.
The receptors of the heart can be imaged with both PET and SPECT tracers. The technique is complex, but has provided important knowledge on the denervation in e.g. diabetes, different cardiomyopathies and in heart transplant recipients. Although the technique has been available for a number of years the clinical application is just becoming a reality. MIBG tracers are being marketed and the potential triage of ICD candidates based on MIBG scans was debated.
Juhani Knuuti - Turku FI – discussed PET based imaging of cardiac metabolism. This complex field was reviewed and new data regarding cardiac efficacy in different cardiomyopathies were discussed. Furthermore, the newest imaging modalities enabling fusion of CT based anatomical (e.g coronary) information and PET based metabolic information is likely to improve the clinical use of viability testing. Evaluation of drug effects on myocardial efficacy was also debated.