PMID- 34450724 OWN - NLM STAT- MEDLINE DCOM- 20210831 LR - 20240403 IS - 1424-8220 (Electronic) IS - 1424-8220 (Linking) VI - 21 IP - 16 DP - 2021 Aug 5 TI - A Dictionary Optimization Method for Reconstruction of ECG Signals after Compressed Sensing. LID - 10.3390/s21165282 [doi] LID - 5282 AB - This paper presents a new approach for the optimization of a dictionary used in ECG signal compression and reconstruction systems, based on Compressed Sensing (CS). Alternatively to fully data driven methods, which learn the dictionary from the training data, the proposed approach uses an over complete wavelet dictionary, which is then reduced by means of a training phase. Moreover, the alignment of the frames according to the position of the R-peak is proposed, such that the dictionary optimization can exploit the different scaling features of the ECG waves. Therefore, at first, a training phase is performed in order to optimize the overcomplete dictionary matrix by reducing its number of columns. Then, the optimized matrix is used in combination with a dynamic sensing matrix to compress and reconstruct the ECG waveform. In this paper, the mathematical formulation of the patient-specific optimization is presented and three optimization algorithms have been evaluated. For each of them, an experimental tuning of the convergence parameter is carried out, in order to ensure that the algorithm can work in its most suitable conditions. The performance of each considered algorithm is evaluated by assessing the Percentage of Root-mean-squared Difference (PRD) and compared with the state of the art techniques. The obtained experimental results demonstrate that: (i) the utilization of an optimized dictionary matrix allows a better performance to be reached in the reconstruction quality of the ECG signals when compared with other methods, (ii) the regularization parameters of the optimization algorithms should be properly tuned to achieve the best reconstruction results, and (iii) the Multiple Orthogonal Matching Pursuit (M-OMP) algorithm is the better suited algorithm among those examined. FAU - De Vito, Luca AU - De Vito L AUID- ORCID: 0000-0003-1896-2614 AD - Department of Engineering, University of Sannio, 82100 Benevento, Italy. FAU - Picariello, Enrico AU - Picariello E AD - Department of Engineering, University of Sannio, 82100 Benevento, Italy. FAU - Picariello, Francesco AU - Picariello F AUID- ORCID: 0000-0001-6854-3026 AD - Department of Engineering, University of Sannio, 82100 Benevento, Italy. FAU - Rapuano, Sergio AU - Rapuano S AD - Department of Engineering, University of Sannio, 82100 Benevento, Italy. FAU - Tudosa, Ioan AU - Tudosa I AUID- ORCID: 0000-0002-5127-578X AD - Department of Engineering, University of Sannio, 82100 Benevento, Italy. LA - eng GR - ARS01_00860/Italian Ministry of Research/ PT - Journal Article DEP - 20210805 PL - Switzerland TA - Sensors (Basel) JT - Sensors (Basel, Switzerland) JID - 101204366 SB - IM MH - Algorithms MH - *Data Compression MH - *Electrocardiography MH - Humans PMC - PMC8398887 OTO - NOTNLM OT - ECG OT - OMP OT - compressed sensing OT - dictionary learning COIS- The authors declare no conflict of interest. EDAT- 2021/08/29 06:00 MHDA- 2021/09/01 06:00 PMCR- 2021/08/05 CRDT- 2021/08/28 01:01 PHST- 2021/06/22 00:00 [received] PHST- 2021/07/30 00:00 [revised] PHST- 2021/08/01 00:00 [accepted] PHST- 2021/08/28 01:01 [entrez] PHST- 2021/08/29 06:00 [pubmed] PHST- 2021/09/01 06:00 [medline] PHST- 2021/08/05 00:00 [pmc-release] AID - s21165282 [pii] AID - sensors-21-05282 [pii] AID - 10.3390/s21165282 [doi] PST - epublish SO - Sensors (Basel). 2021 Aug 5;21(16):5282. doi: 10.3390/s21165282.