Radiation dose and diagnostic accuracy of multidetector computed tomography for the detection of significant coronary artery stenoses: a meta-analysis.

We conducted a meta-analysis evaluating the critical ratio between effective radiation dose (ED), feasibility (Fe) and diagnostic accuracy (Ac) of multidetector computed tomography (MDCT) for the detection of significant coronary artery disease. By using our predetermined criteria, we selected human studies published in English in which the ED and raw data of Ac vs. invasive coronary angiography in a segment based model were specified. Data from 31 studies including 3661 patients (mean age 61.9 ± 4.5 years, heart rate 62.5 ± 6.7 bpm) and 50,236 coronary artery segments were analysed and are reported. Overall, Fe, sensitivity, specificity, negative predictive value, positive predictive value, Ac and ED were 95%, 90%, 96%, 99%, 69%, 95% and 10.4 ± 5.4 mSv, respectively. Multivariate analysis showed that prospective ECG-gating (-8.8 mSv CI95% -13.4 to -4.3 mSv, p=0.001), dual-source (-3.7 mSv CI95% -7.9 to 0 mSv, p=0.05) and BMI-adapted scanning protocols (-4.5 mSv CI95% -8.7 to -2.7 mSv, p=0.03) were independent predictors of ED reduction. In patients with low heart rate, the best compromise between ED, Fe and Ac (2.5 mSv, 97% and 98%, respectively) was obtained combining prospective ECG-gating and BMI-adapted scanning protocols, while in patients with high heart rate the strategy associated with the best results (10 mSv, 98% and 97%, respectively) was the use of dual-source MDCT with retrospective ECG gating and modulation dose. In conclusion, careful selection of CT scanning protocols according to the patient's characteristics is critical for keeping the radiation exposure "as low as reasonably achievable" (ALARA) without impairing Fe and Ac.

Potential advantages of cell administration on the inflammatory response compared to standard ACE inhibitor treatment in experimental myocardial infarction.

BACKGROUND: Bone Marrow (BM) progenitor cells can target the site of myocardial injury, contributing to tissue repair by neovascolarization and/or by a possible direct paracrine effect on the inflammatory cascade. Angiotensin Converting Enzyme inhibitors (ACE-I) are effective in reducing mortality and preventing left ventricular (LV) function deterioration after myocardial infarction. METHODS: We investigated the short term effects of BM mononuclear cells (BMMNCs) therapy on the pro-inflammatory cytokines (pro-CKs) and on LV remodelling and compared these effects over a standard ACE-I therapy in a rat model of myocardial cryodamage. Forty two adult inbread Fisher-F344 rats were randomized into three groups: untreated (UT; n = 12), pharmacological therapy (ACE-I; n = 14, receiving quinapril), and cellular therapy (BMMNCs; n = 16, receiving BMMNCs infusion). Rats underwent to a standard echocardiogram in the acute setting and 14 days after the damage, before the sacrifice. Pro-CKs analysis (interleukin (IL)1beta, IL-6, tumor necrosis factor (TNF)alpha was performed (multiplex proteome arrays) on blood samples obtained by direct aorta puncture before the sacrifice; a control group of 6 rats was considered as reference. RESULTS: Concerning the extension of the infarcted area as well as the LV dimensions, no differences were observed among the animal groups; treated rats had lower left atrial diameters and higher indexes of LV function. Pro-Cks were increased in infarcted-UT rats if compared with controls, and significantly reduced by BMMNCs and ACE-I ; TNFalpha inversely correlated with LV fractional shortening. CONCLUSION: After myocardial infarction, both BMMNCs and ACE-I reduce the pattern of pro-Ck response, probably contributing to prevent the deterioration of LV function observed in UT rats.