Guidelines for the diagnosis and treatment of circulatory diseases in the context of the COVID-19 pandemic

No abstract

Cardiac resynchronization therapy (CRT) has been shown as an essential treatment of patients with heart failure, leading to improvements in symptoms, left ventricular (LV) function, and survival. However, up to 30% of appropriately selected patients remain nonresponders to CRT. The aim of our study was to test a hypothesis on the impact of lead positioning in the ventricular walls on CRT response in patients with advanced chronic heart failure with and without pre-operative inter and intraventricular myocardial dyssynchrony. We examined 53 guideline-selected CRT candidates. Response to CRT was defined in 6 months after implantation of CRT devices. All patients underwent standard and Doppler echocardiography for assessment of LV function and mechanical dyssynchrony. Individual right ventricular (RV) and LV lead tip position, inter-lead distance, and the horizontal and vertical components were measured on the radiograph images with using an automated custom made software Our results showed that the RLV inter-lead distance is an essential parameter correlated with the CRT outcomes. A logistic model comprising the RLV inter-lead distance with parameters of dyssynchrony demonstrated a high predictive power for odds of CRT success.

Noninvasive electrocardiographic imaging (ECGI) with magnetic resonance tomography (MRI) is a promising technology raising clinical interest. In this manuscript, the method of qualitative comparison of late electrical activation zone's position and area of fibrosis based on 17-segment approach is presented. To demonstrate performance of the proposed method, we studied sixty one patients scheduled as a potential candidates for cardiac resynchronization therapy. ECGI was performed using Amycard 01C EP LAB (EP Solutions SA, Switzerland). The late activation zone (LAZ) on a wide QRS complex with different morphology pattern was variable from anterior till inferior left ventricle (LV) wall. According to the MRI data, 41(67%) patients had fibrosis areas which did not coincide with the LAZ. 9(15%) participants had transmural scar involving epicardium of LV which localization coincided with the LAZ. In the remaining 11(18%) cases nontransmural scar excluding epicardial layer coincided with the LAZ. Taking these results into account, it is reasonable to assume that comparative qualitative analysis of ECGI and MRI data demonstrates coincidence of LAZ with fibrosis areas only in 33% of cases.