Radiation Dose Reduction Using a Novel Fluoroscopy System in Patients Undergoing Diagnostic Invasive Coronary Angiography.

BACKGROUND: Invasive coronary angiography (ICA) still causes a significant amount of radiation exposure for patients and operators. In February 2017, the Azurion system was introduced, a new-generation fluoroscopy image acquisition and processing system. Radiation exposure in patients undergoing ICA was assessed comparing the novel Azurion 7 F12 angiography system to its predecessor Allura Xper in a randomized manner. METHODS: Radiation exposure was prospectively analyzed in 238 patients undergoing diagnostic ICA. Patients were randomly assigned to the novel Azurion system (119 patients) or its predecessor Allura Xper system (119 patients). In each patient, 8 predefined standard projections (5 left coronary artery, 3 right coronary artery) were performed. Image quality was quantified by grading of the images on the basis of a 5-point grading system. RESULTS: Radiation dose area product was significantly lower in the Azurion group 109 (interquartile range [IQR 75-176] cGy cm) compared with the Allura Xper group 208 [IQR 134-301] cGy cm (P<0.001). Body mass index (26.6 [IQR 23.9-29.7] kg/m vs. 26.2 [IQR 24.2-29.4] kg/m; P=0.607), body surface area (1.96 [IQR 1.81-2.11] m vs. 1.90 [IQR 1.77-20.4] m; P=0.092), and procedure duration (1.5 [IQR 1.2-2.3] min vs. 1.6 [IQR 1.2-2.5] min; P=0.419) were similar in both groups. Images from the Azurion system were at least of equal quality compared with Allura Xper (image quality grade 4.82±0.45 vs. 4.75±0.52, P=0.43). CONCLUSION: Use of the novel Azurion 7 F12 angiography system resulted in a significant reduction of dose area product in patients undergoing diagnostic ICA by 56%.

Significant Radiation Dose Reduction Using a Novel Angiography Platform in Patients Undergoing Cryoballoon Pulmonary Vein Isolation.

OBJECTIVES: Cryoballoon pulmonary vein isolation (cPVI) in patients with atrial fibrillation requires fluoroscopic guidance, causing a relevant amount of radiation exposure. Strategies to reduce radiation exposure in electrophysiologic procedures and specifically cPVI are of great importance. The aim of this study was to evaluate a possible reduction of radiation dose using the novel Azurion 7 F12 x-ray system compared with its predecessor Allura FD10. METHODS: In February 2017, the Philips Azurion angiography system was introduced, combining the Allura Clarity radiation dose reduction technology with a more powerful generator, improved image resolution, and a large screen display. In 173 patients undergoing cPVI by a single experienced operator in our institution between December 2016 and April 2018, dose area products (cGy×cm) and image quality were compared using Azurion 7 F12 or Allura FD10 angiography system. RESULTS: A significant reduction in total radiation dose expressed as a dose area products of 524 (332; 821) cGy×cm on the Allura system compared with 309 (224; 432) cGy×cm on the Azurion system was observed (P<0.001). The number of imaging scenes recorded were 14.7 versus 13.9, and mean overall imaging quality scores (grading 4.85±0.4 with Azurion vs. 4.80±0.4 with Allura, P=0.38) and scores based on specific quality parameters were similar in both groups. CONCLUSION: Use of the new Azurion 7 F12 angiography system substantially reduced radiation doses compared with the previous generation reference system, Allura Clarity, without compromising imaging quality in patients undergoing cryoballoon pulmonary vein isolation.

Noninvasive quantitative assessment of microcirculatory disorders of the upper extremities with 2D fluorescence optical imaging.

BACKGROUND: Quantitative Imaging of microcirculatory disorders is challenging. OBJECTIVE: To investigate the feasibility of 2D Fluorescence Optical Imaging (FOI) for characterization and quantification of microcirculatory disorders in peripheral arterial occlusive disease (PAOD) of the upper extremity. METHODS: 9 patients with various clinical presentations of PAOD of the upper extremity were included. Quantitative analysis of both hands was performed by assessing the fluorescence intensity of Indocyanine Green (ICG) dynamically over a time period of 360 seconds. Analysis of the signal intensity within multiple regions of both hands was calculated and time-dependent perfusion curves for each region of interest were plotted over time. RESULTS: Compared to the healthy, vascular non-impaired segments, pathological segments with an impaired tissue perfusion were identified through a decreased rate of early tissue enhancement (p = 0.02) and increased signal intensity of the optical perfusion agent per second (p < 0.001). The affected segments showed a decreased maximum signal intensity and a prolonged interval to reach the maximum signal intensity (time to peak). CONCLUSION: 2D FOI allows quantitative assessment of the peripheral microcirculation in various vascular pathophysiologies and is able to detect the impaired tissue perfusion in patients with vascular disorders of the upper extremity.