Noninvasive blood glucose (NIBG) measurement technique has been explored for the last three decades to facilitate diabetes management. Photoplethysmogram (PPG) signal may be used to measure the variations in blood glucose concentration. However, the literature reveals that physiological perturbations such as temperature, skin moisture, and sweat lead to less accurate NIBG measurements. The task of minimizing the effect of these perturbations for accurate measurements is an important research area. Therefore, in the present work, galvanic skin response (GSR) and temperature measurements along with PPG were used to measure blood glucose noninvasively. The data extracted from the sensors were used to estimate blood glucose concentration with the help of two machine learning (ML) techniques, i.e., multiple linear regression (MLR) and artificial neural network (ANN). The accuracy of proposed multisensor system was evaluated by pairing and comparing noninvasive measurements with invasively measured readings. The study was performed on 50 nondiabetic subjects with body mass index (BMI) 27.3 ± 3 kg/m². The results revealed that multisensor NIBG measurement system significantly improves mean absolute prediction error and correlation coefficient in comparison to the techniques reported in the literature.

Introduction: Catheter based Interventional procedures have become an indispensable treatment option for patients contraindicated for surgical heart valve replacement . The broad spectrum of disease that affect the mitral valve have increased the need for a transcatheter mitral valve replacement (TMVR) device. As complex as the mitral valve anatomy is, so are challenges in the development of a TMVR device. Areas covered: This review article analyses the challenges in the development of the TMVR device from an engineering perspective of material and device design. The major sections in this paper discusses the engineering challenges in the development of TMVR device, material & design considerations, surface coating, present and future of TMVR, delivery catheter specifications and commercial prospects of the TMVR. This article highlights the current status in the development of each of the devices based on the outcome clinical trials and case studies. The literature analysis was carried out using the keywords search. Expert commentary: This section concludes with the need for collaborative efforts from the medical and engineering expertise for the successful development of TMVR device. Overcoming the anatomical challenges with engineering innovations would create new frontier in TMVR technologies.