Induction Dosage of Propofol for Repeated Sedations in Children With Hematological Disorders.

Pediatric patients with hematologic malignancies require several procedural sedations by means of propofol infusion. We retrospectively analyzed the medical records of leukemic pediatric patients who had undergone procedural sedations at an Italian tertiary referral center (San Gerardo Hospital, Monza) from January 2011 to November 2013. We retrieved the following: demographics; diagnosis; chemotherapy phase; use of corticosteroids; induction dosage of propofol, fentanyl and/or ketamine; and the type of procedure. We used a multivariate linear mixed model to evaluate the factors affecting induction propofol dose. We analyzed 1459 procedures (59% lumbar punctures, 31% bone marrow aspirations) performed on 96 children (7 [4-10] y old, 24 [16-34] kg, 37% female) admitted for acute lymphoblastic leukemia (80%), lymphoma (11%), and acute myeloid leukemia (7%). The induction propofol dose increased by 0.03 mg/kg per each procedure (P<0.05), from 2.6 (2.0-3.2) to 3.5 (2.6-4.3) mg/kg at the first and the last procedure, respectively. Higher age, weight, and use of ketamine were associated to lower propofol dosage (P<0.01), while combined procedures increased propofol dosage (P<0.01). In a large cohort of leukemic pediatric patients undergoing procedural sedation, the induction dose of propofol was increased over time, regardless of weight, age, use of corticosteroids, diagnosis, and treatment phase.

Left atrium and pulmonary vein imaging using sub-millisiviert cardiac computed tomography: Impact on radiofrequency catheter ablation cumulative radiation exposure and outcome in atrial fibrillation patients.

BACKGROUND: The outcome of radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF) has improved thanks to left atrium (LA) anatomy reconstruction by cardiac computed tomography (CCT). A new model-based iterative reconstruction algorithm (MBIR) provides image noise reduction achieving effective radiation dose (ED) close to chest X-ray exposure. Aim of this study was comparing RFCA procedural characteristics, AF recurrence and radiation exposure between patients in whom RFCA was guided by CCT image integration with MBIR versus a CCT standard protocol. METHODS: Three-hundred consecutive patients with drug-refractory AF were studied with CCT using MBIR (Group 1; N:150) or CCT with standard protocol (Group 2; N:150) for LA evaluation and treated by image integration-supported RFCA. Image noise, signal to noise ratio (SNR), contrast to noise ratio (CNR), RFCA procedural characteristics, rate of AF recurrence and radiation exposure were compared. RESULTS: Group 1 showed higher SNR (25.9±7.1 vs. 16.2±4.8, p<0.001) and CNR (23.3±7.1 vs. 12.2±4.2, p<0.001) and lower image noise (22.3±5.2 vs. 32.6±8.1 HU, p<0.001), fluoroscopy time (21±12 vs. 29±15min, p<0.01) and procedural duration (135±89 vs. 172±55, p<0.001). Group 1 showed a 94% reduction of ED as compared to Group 2 (CCT-ED related: 0.41±0.04 vs. 6.17±4.11mSv, p<0.001; cumulative CCT+RFCA-ED related: 21.9±17.9 vs. 36.0±24.1mSv, p<0.001) with similar rate of AF recurrence (25% vs. 29%, p=0.437). CONCLUSIONS: CCT with MBIR allows accurate reconstruction of LA anatomy in AF patients undergoing RFCA with a sub-millisievert ED and comparable success rate of RFCA as compared to a standard CCT scan protocol.

Rationale and design of the PERFECTION (comparison between stress cardiac computed tomography PERfusion versus Fractional flow rEserve measured by Computed Tomography angiography In the evaluation of suspected cOroNary artery disease) prospective study.

BACKGROUND: Non-invasive stress tests are commonly used as gatekeepers to invasive coronary angiography (ICA) in patients with suspected coronary artery disease (CAD). New computed tomography angiography (CTA) techniques such as fractional flow reserve calculated by CTA (FFRCT) and stress myocardial computed tomography perfusion (CTP) have emerged as potential strategies to combine anatomical and functional evaluation of CAD in one technique. The aim of this study is to compare per-vessel diagnostic accuracy of FFRCT versus stress myocardial CTP for the detection of functionally significant coronary artery disease (CAD), using invasive FFR as the reference standard. METHODS: Subjects with suspected CAD due to chest pain who have no contra-indications to FFRCT or stress myocardial CTP and who are referred for non-emergent, clinically indicated invasive coronary angiography (ICA), will be enrolled. A total of 300 subjects will be enrolled within 24 months. RESULTS: The primary study endpoint will be the comparison of per-vessel diagnostic accuracy of CTA versus FFRCT versus stress myocardial CTP for the diagnosis of hemodynamically significant stenosis as defined by invasive FFR ≤0.80. CONCLUSIONS: In the PERFECTION study, the comparison between FFRCT and stress myocardial CTP will provide understanding about which technology is more accurate for the diagnosis of functionally significant CAD.

Comparison of cardiac computed tomography versus cardiac magnetic resonance for characterization of left atrium anatomy before radiofrequency catheter ablation of atrial fibrillation.

BACKGROUND: The outcome of radiofrequency catheter ablation (RFCA) has been improved by the pivotal role of cardiovascular imaging such as cardiac computed tomography (CCT) or cardiac magnetic resonance (CMR) for the characterization of left atrium (LA) anatomy before RFCA. The aim of this study is to compare the procedural characteristics, overall radiation exposure and clinical outcomes between RFCA guided by image integration with CCT versus CMR. METHODS: Four-hundred patients with drug-refractory paroxysmal or persistent AF referred to RCFA were matched with the propensity score matching analysis to CCT (n: 200) or CMR (n: 200) for evaluation of LA before RFCA procedure. Left atrium diameter, left atrium volume, variant of pulmonary veins' anatomy, pulmonary veins' ostial dimensions, procedural characteristics, overall radiation exposure and rate of AF recurrence after RFCA were measured and compared between the two groups. RESULTS: The 2 groups were homogeneous with similar follow-up (557 ± 302 vs. 523 ± 265 days, respectively, p:0.24). The CCT group showed higher LA volume vs. CMR group (117 ± 46 vs. 101 ± 40 mL, p<0.001). No differences were observed regarding procedural characteristics. AF recurrence at follow-up was similar (29% vs. 26%, p:0.5) despite a higher radiation exposure in the CCT group vs. CMR group (40.4 ± 23.7 mSv vs. 32.8 ± 23.5 mSv, p<0.005). LA volume detected by CMR was the most robust independent predictor of AF recurrence at multivariate analysis [(HR: 1.08 (1.01-1.15), p: 0.02]. CONCLUSIONS: CCT and CMR provide similar information before RFCA. However, RFCA CMR-guided is associated with a lower overall cumulative radiation despite similar outcome in comparison with CCT-guided RFCA.