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To investigate and describe the distribution of aortic and cerebral blood flow (CBF) in patients with severe valvular aortic stenosis (AS) before and after aortic valve bypass (AVB) surgery.We enrolled 10 consecutive patients who underwent AVB surgery for severe AS. Cardiovascular magnetic resonance imaging (CMR) and brain magnetic resonance imaging were performed as baseline before surgery and twice after surgery. Quantitative flow measurements were obtained using 1.5-T magnetic resonance imaging (MRI) scanner phase-contrast images of the ascending aorta, descending thoracic aorta (3 cm proximally and distally from the conduit-to-aorta anastomosis), and ventricular outflow portion of the conduit. The evaluation of CBF was performed using 3.0-T MRI scanner arterial spin labeling (ASL) through sequences acquired at the gray matter, dorsal default-mode network, and sensorimotor levels.Conduit flow, expressed as the percentage of total antegrade flow through the conduit, was 63.5 ± 8% and 67.8 ± 7% on early and mid-term postoperative CMR, respectively (P .05). Retrograde perfusion from the level of the conduit insertion in the descending thoracic aorta toward the aortic arch accounted for 6.9% of total cardiac output and 11% of total conduit flow. We did not observe any significant reduction in left ventricular stroke volume at postoperative evaluation compared with preoperative evaluation (P = .435). No differences were observed between preoperative and postoperative CBF at the gray matter, dorsal default-mode network, and sensorimotor levels (P = .394).After AVB surgery in patients with severe AS, cardiac output is split between the native left ventricular outflow tract and the apico-aortic bypass, with two-thirds of the total antegrade flow passing through the latter and one-third passing through the former. In our experience, CBF assessment confirms that the flow redistribution does not jeopardize cerebral blood supply.

We report a case of a woman at 32nd gestational week, admitted for resting dyspnea, showing left atrial (LA) myxoma. Cardiac myxomas are the most common primary benign tumors of the heart. The incidence of cardiac myxomas diagnosed in pregnancy is extremely low. In the present case, cesarean delivery and concomitant surgical resection of LA myxoma were both delayed after corticosteroid prophylaxis in order to reduce neonatal cerebral, intestinal, and pulmonary complications. .

Purpose Ventricular Assist Device (VAD) improves quality of life, but in patients requiring also radiotherapy its performance might be conditioned. We attempted measurements of basic operating parameters in vitro setting under high-energy photon beams with Jarvik2000 VAD. Methods Jarvik2000 was a turbine pump (diameter = 2.5 cm, length = 5.5 cm, weight = 85 g) with neodymium-iron-boron magnet impeller supported by ceramic bearings and housed inside a titanium-welded shell. Implanted in left ventricle, the VAD made blood flow into the descending thoracic aorta and ensured perfusion of the organs by alternating two operating states: S1 (high-speed in 64 sec.) and S2 (low-speed in 8 sec). The device was connected to an external FlowMaker controller delivering power via a tunnelled driveline from a lithium ion battery. The in vitro setting consisted of a RW3 phantom with Plexiglas siliconized box filled with deionized water containing the pump. This was located and irradiated at the isocenter of a Synergy Agility (Elekta, Crawley) using 10MV photon beam, 1000 M.U. and a 20 × 20 cm2 field. Voltage, current and frequency parameters of VAD alternating power supply were first measured to establish reference values in the BaseLine session. Then they were compared to those obtained immediately before, during and after irradiation (“PreRad”, “Irradiation” and “PostRad” sessions respectively) and finally two months later (“Final Verification” session). Results No changes were recorded in the registered parameters after each session. The VAD system worked stably. Figure shows both behaviour of voltage(mV), current(mA) and frequency(Hz) in S1 and S2 operating states during BaseLine session(a) and voltage(b), current(c) and frequency(d) of the five sessions during S1 state. Conclusions VAD system continued its proper work after irradiation. To guarantee VAD functionality for any type of dose, future measurements will be carried out by simulating some typical radiotherapy treatments using 18MV photon beams to see whether neutron activation affects the components of the system. Download : Download high-res image (196KB) Download : Download full-size image