Comparison of the Bentall procedure versus valve-sparing aortic root replacement.

Bentall and valve-sparing root replacement (VSRR) procedures are established treatments for aortic root disease. We present a single-center retrospective analysis comparing outcomes of bioprosthetic Bentall (BB), mechanical Bentall (MB), and VSRR patients from November 2007 to October 2016. Survival analysis was performed to evaluate the composite endpoint of freedom from recurrent aortic insufficiency, reoperation, or death. Of the 170 patients, BB was performed in 36 patients, MB in 63 patients, and VSRR in 71 patients. For BB, MB, and VSRR, the mean age was 63.8, 45.5, and 49.2 years (P < 0.001), respectively. Additionally, significantly more patients in the MB group (n = 32, 50.8%, P < 0.001) than in the BB and VSRR groups had prior cardiac surgeries. Cardiopulmonary bypass time and cross-clamp time were significantly longer in the VSRR group (P = 0.04 and 0.0005, respectively). Despite the complexity of the procedure, VSRR patients had higher combined freedom from death and reoperation than patients in the BB or MB groups. Elective Bentall root replacement is an excellent option for patients with root disease. Patients undergoing Bentall tend to have more severe or emergent cases, making them unlikely candidates for VSRR. VSRR in experienced centers carries equivalent morbidity and mortality and improved survival.

Assessment of a noninvasive optical photoplethysmography imaging device with dynamic tissue phantom models.

Noncontact photoplethysmography (PPG) has been studied as a method to provide low-cost, noninvasive, two-dimensional blood oxygenation measurements and medical imaging for a variety of near-surface pathologies. To evaluate this technology in a laboratory setting, dynamic tissue phantoms were developed with tunable parameters that mimic physiologic properties of the skin, including blood vessel volume change, pulse wave frequency, and tissue scattering and absorption. Tissue phantoms were generated using an elastic tubing to represent a blood vessel where the luminal volume could be modulated with a pulsatile fluid flow. The blood was mimicked with a scattering and absorbing motility standard, and the tissue with a gelatin-lipid emulsion hydrogel. A noncontact PPG imaging system was then evaluated using the phantoms. Noncontact PPG imaging accurately identified pulse frequency, and PPG signals from these phantoms suggest that the phantoms can be used to evaluate noncontact PPG imaging systems. Such information may be valuable to the development of future PPG imaging systems.