Implementation of an epicardial implantable MEMS sensor for continuous and real-time postoperative assessment of left ventricular activity in adult minipigs over a short- and long-term period.

The sensing of left ventricular (LV) activity is fundamental in the diagnosis and monitoring of cardiovascular health in high-risk patients after cardiac surgery to achieve better short- and long-term outcome. Conventional approaches rely on noninvasive measurements even if, in the latest years, invasive microelectromechanical systems (MEMS) sensors have emerged as a valuable approach for precise and continuous monitoring of cardiac activity. The main challenges in designing cardiac MEMS sensors are represented by miniaturization, biocompatibility, and long-term stability. Here, we present a MEMS piezoresistive cardiac sensor capable of continuous monitoring of LV activity over time following epicardial implantation with a pericardial patch graft in adult minipigs. In acute and chronic scenarios, the sensor was able to compute heart rate with a root mean square error lower than 2 BPM. Early after up to 1 month of implantation, the device was able to record the heart activity during the most important phases of the cardiac cycle (systole and diastole peaks). The sensor signal waveform, in addition, closely reflected the typical waveforms of pressure signal obtained via intraventricular catheters, offering a safer alternative to heart catheterization. Furthermore, histological analysis of the LV implantation site following sensor retrieval revealed no evidence of myocardial fibrosis. Our results suggest that the epicardial LV implantation of an MEMS sensor is a suitable and reliable approach for direct continuous monitoring of cardiac activity. This work envisions the use of this sensor as a cardiac sensing device in closed-loop applications for patients undergoing heart surgery.

[Clinical experience with an antaminic drug in the treatment of post-traumatic and vasomotor headaches]. / Esperienze cliniche con un farmaco antiaminico nel trattamento delle cefalee vasomotorie e post-traumatiche.

After some brief remarks on the pathogenesis of vasomotor cephalea, the properties of the antiaminic drug BC 105 (Sandomigran) are described and the results reported of using it in 171 patients suffering from cephalea of three types: vasomotor cephalea in 50 cases, vasomotor cephalea with associated neurosic component in 26 cases, and post-traumatic cephalea in 95 cases. In the first two types, the positive results obtained confirm the usefulness of BC 105 in basic treatment of vasomotor cephalea. In post-traumatic cephalea which is a notoriously difficult therapeutic problem, the results obtained, although only partially positive, are worthy of the fullest consideration.