687Cardiomyoapthic aetiology affects the distribution of endocardial electrical latency; results from a multi-centre registry
Year: 2018
Type: conference-abstract
Abstract: Background: Biventricular endocardial (BIV ENDO) pacing may offer a potential benefit over standard CRT, especially in non-responders however the optimal left ventricular endocardial (LV ENDO) pacing site displays marked inter and intra-patient variability. Identifying and targeting late activating, viable tissue appears important. Objective: We sought to test the hypothesis that lateral LV ENDO sites would consistently display the latest electrical activation, as defined by the Q-LV, regardless of the underlying cardiomyoapthic process. Methods: Registry of acute LV endocardial pacing studies from five international centres: Johns Hopkins- USA, Bordeaux- France, Leiden- The Netherlands, Oxford- United Kingdom and King’s College London- United Kingdom. Q-LV was measured via a roving endocardial catheter and plotted onto circumferential polar plot. Results: 37 patients had AHR and QLV measurements incorporating 191 endocardial pacing locations Patients were predominantly male with a mean age of 68.8±12.8 years, the mean LVEF was 25.9±7.6%. The mean QRS duration was 166±28.0ms. 68% (n=25) of patients had an ischaemic (ICM) aetiology. Cardiomyopathic aetiology had a significant impact on the distribution of electrical latency in endocardial tissue. Across all patients, lateral LV ENDO locations tended to display the latest activation, see Figure 1a. Amongst non-ischaemic (NICM) patients Q-LV predictably increased from septal to lateral segments, see Figure 1b. In ICM patients, a greater variance in Q-LV was observed due to the impact of the underlying substrate and scar on electrical activation, see Figure 4c. During univariate analysis, greater variance in the Q-LV was observed between each LV ENDO location in patients with an ICM than was seen with a DCM (p < 0.001 vs p = 0.17). Conclusions: Lateral LV ENDO pacing locations were typically associated with greater degrees of electrical delay. This was particularly true amongst patients with a NICM aetiology, where the delay in activation progressively increased, in proportion to the distance from the septum. In these cases, targeting a lateral segment displaying late activation would seem to represent an optimal strategy. Amongst ICM patients this progressive pattern of incremental activation delay was not observed however, lateral locations were found to possess the latest activation times, as defined by Q-LV. Abstract 687 Figure. Distribution of endocardial Q-LV
Source: EP Europace
Language: English
Subfield: Cardiology and Cardiovascular Medicine
Field: Medicine
Domain: Health Sciences
Open Access status: bronze
OpenAlex ID: W2791858730