Non-invasive assessment of coronary artery disease with CT coronary angiography and SPECT: a novel dose-saving fast-track algorithm

PURPOSE: To validate a new low-dose and rapid stepwise individualized algorithm for non-invasive assessment of ischemic coronary artery disease by sequential use of prospectively ECG-triggered low-dose CT coronary angiography (CTCA) and low-dose single-photon emission computed tomography myocardial perfusion imaging (SPECT-MPI). METHODS: Forty patients referred for elective invasive coronary angiography (CA) were prospectively enrolled to undergo a comprehensive non-invasive evaluation with low-dose CTCA and a dose-reduced stress/rest SPECT-MPI scan (using dedicated reconstruction algorithms for low count scans). The following algorithm was reviewed: CTCA first, followed by a stress-only MPI if a coronary stenosis (>/= 50% diameter narrowing) or equivocal findings were observed. Only abnormal stress MPI scans were followed by rest MPI. The accuracy of the individualized algorithm to predict coronary revascularization and its mean effective radiation dose were assessed. RESULTS: CTCA documented CAD in 18 and equivocal findings in two patients, thus, requiring additional stress MPI scans. Of these, 16 were abnormal, therefore requiring a rest MPI scan, revealing ischemia in 15 patients. Sensitivity, specificity, negative and positive predictive value, and accuracy of the individualized algorithm for predicting coronary revascularization was 93.3%, 96.0%, 96.0%, 93.3% and 95.0% on a per-patient base. The mean effective radiation dose was significantly lower for the individualized (4.8 +/- 3.4 mSv) versus the comprehensive method (8.1 +/- 1.5 mSv) resulting in a total population radiation dose reduction of 132.6 mSv. CONCLUSION: This new individualized low-dose algorithm allows rapid and accurate prediction of invasive CA findings and of treatment decision with minimized radiation dose

PET radiopharmaceuticals in Europe : Current use and data relevant for the formulation of summaries of product characteristics (SPCs)

The increasing use of radiopharmaceuticals for positron emission tomography (PET) has come to the attention of regulatory bodies. In order to help authorities in all aspects, the EANM has formed a task group for licensing PET radiopharmaceuticals; this group has surveyed the use of these compounds in Europe by a questionnaire. The number of PET centres that responded to the questionnaire was 26, which included more than 90% of the larger European PET centres. The survey showed that 2-[18F]fluoro-2-deoxyglucose is by far the most important PET radiopharmaceutical with more than 200 applications per week, followed by [15O]water, [15O]carbonmonoxide, [13N]ammonia, [11C]-l-methionine, andl-6-[18F]fluoro-DOPA. More than 25 other PET radiopharmaceuticals are in regular use, however, at rather low application frequencies. The data were used by the European Pharmacopoeia Commission for its priority rating for requesting the formulation of monographs. Since it is likely that group registrations will be issued by authorities for the PET radiopharmaceuticals, relevant data on toxicity and dosimetry for the formulation of summaries of product characteristics have been collected by the task group as well