Segmented cardiac acquisitions generally require the use of an electrocardiogram (ECG) in combination with a breathhold or a respiratory navigator placed on the diaphragm. These techniques necessitate patient cooperation and increase the complexity of cardiac imaging. The ECG signal may be distorted inside the magnet by interferences from radiofrequency and gradient action. Breathhold acquisiti...

Image guidance during cardiac interventional procedures (IP) using cardiac C-arm CT systems is desirable for many procedures. Applying the concept of retrospective electrocardiogram gating (ECG) to the acquisition of multiple, ECG-triggered rotational acquisitions using a C-arm system allows the 3D+t reconstruction of the heart. The process of retrospective gating is a crucial component of 3-D ...

BACKGROUND Fetal cardiovascular magnetic resonance (CMR) imaging may provide a valuable adjunct to fetal echocardiography in the evaluation of congenital cardiovascular pathologies. However, dynamic fetal CMR is difficult due to the lack of direct in-utero cardiac gating. The aim of this study was to investigate the effectiveness of a newly developed Doppler ultrasound (DUS) device in humans fo...

Power gating technique reduces leakage power in the circuit. However, power gating leads to large voltage fluctuation on the power rail during power gating mode to active mode due to the package inductance in the Printed Circuit Board. This voltage fluctuation may cause unwanted transitions in neighboring circuits. In this work, a power gating architecture is developed for minimizing power in a...

On-gating current from the Kv1.5 cardiac delayed rectifier K+ channel expressed in HEK-293 cells was separated into two distinct charge systems, Q 1 and Q 2, obtained from double Boltzmann fits to the charge-voltage relationship. Q 1 and Q 2 had characteristic voltage dependence and sensitivity with half-activation potentials of -29.6 ± 1.6 and -2.19 ± 2.09 mV and effective valences of 1.87 ± 0...

With the arrival of increasingly higher resolution PET systems, small amounts of motion can cause significant blurring in the images, compared to the intrinsic resolutions of the scanners. In this work, we have reviewed advanced correction methods for the three cases of (i) unwanted patient motion, as well as motions due to (ii) cardiac and (iii) respiratory cycles. For the first type of ...

Introduction: High quality dynamic cardiovascular MRI requires synchronization of the data acquisition and cardiac pulsatility. In most clinical applications, this is accomplished with prospective cardiac gating with an ECG or pulse oximeter (PO) signal. This approach results in incomplete coverage of the cardiac cycle (CC) because a rejection window (usually 10% of CC) at the end of the cardia...