Enhancing ECG readability in LVAD patients: A comparative analysis of Denoising techniques with an emphasis on discrete wavelet transform.

BACKGROUND: Electrocardiograms (ECGs) are vital for diagnosing cardiac conditions but obtaining clean signals in Left Ventricular Assist Device (LVAD) patients is hindered by electromagnetic interference (EMI). Traditional filters have limited efficacy. There is a current need for an easy and effective method. METHODS: Raw ECG data obtained from 5 patients with LVADs. LVAD types included HeartMate II, III at multiple impeller speeds, and a case with HeartMate III and a ProtekDuo. ECG spectral profiles were examined ensuring the presence of diverse types of EMI in the study. ECGs were then processed with four denoising techniques: Moving Average Filter, Finite Impulse Response Filter, Fast Fourier Transform, and Discrete Wavelet Transform. RESULTS: Discrete Wavelet Transform proved as the most promising method. It offered a one solution fits all, enabling automatic processing with minimal user input while preserving crucial high-frequency components and reducing LVAD EMI artifacts. CONCLUSION: Our study demonstrates the practicality and efficiency of Discrete Wavelet Transform in obtaining high-fidelity ECGs in LVAD patients. This method could enhance clinical diagnosis and monitoring.

Discordant vs. concordant left bundle branch block: A potential clinical significance.

AIM: LBBB in heart failure patients has prognostic significance. Subtypes of LBBB (concordant and discordant) have not been considered when considering management. The aim of this study is to explore the clinical difference between the two subtypes. METHODS: 216 patients with LBBB were included and categorized into concordant (LBBBC) and discordant (LBBBD) groups. RESULTS: Of the 216 patients (age 69.13±11.7; 56% male 44% female), 133 (61.5%) were LBBBD and 83 (38.5%) were LBBBC. LBBBD patients presented with lower LVEF (mean 36% vs 51%; P<0.001), wider QRS (mean 160 ms vs 151 ms; P<0.001), larger LA (mean 45 cm(2) vs 40 cm(2); P<0.001), moderate to severe mitral and tricuspid regurgitation (17% vs 3%; P<0.05, 10% vs 1%; P<0.05 respectively), CKD (41% vs 18%; P<0.001), COPD (4.6% vs 0%; P<0.01), CAD (67% vs 36%; P<0.001), and CABG (39% vs 16%; P<0.001). CONCLUSION: LBBBD is significantly associated with worse cardiac function and clinical characteristics.