Right ventricular free wall longitudinal strain is independently associated with mortality in mechanically ventilated patients with COVID-19

Abstract

Background: Right ventricular (RV) dysfunction has been commonly reported in patients with Coronavirus disease 2019 (COVID-19), and is associated with mortality in mixed cohorts of patients requiring and not requiring invasive mechanical ventilation (IMV). Using RV-speckle tracking echocardiography (STE) strain analysis, we aimed to identify the prevalence of RV dysfunction (diagnosed by abnormal RV-STE) in patients with COVID-19 that are exclusively undergoing IMV, and assess association between RV dysfunction and 30 day mortality. We performed a prospective multicentre study across 10 ICUs in Scotland from 2/9/20 to 22/3/21. One-hundred-and-four echocardiography scans were obtained from adult patients at a single timepoint between 48 h after intubation, and day 14 of intensive care unit admission. We analysed RV-STE using RV free-wall longitudinal strain (RVFWLS), with an abnormal cutoff of > −20%. We performed survival analysis using Kaplan–Meier, log rank, and multivariate cox-regression (prespecified covariates were age, gender, ethnicity, severity of illness, and time since intubation). Results: Ninety-four/one-hundred-and-four (90.4%) scans had images adequate for RVFWLS. Mean RVFWLS was −23.0% (5.2), 27/94 (28.7%) of patients had abnormal RVFWLS. Univariate analysis with Kaplan–Meier plot and log-rank demonstrated that patients with abnormal RVFWLS have a significant association with 30-day mortality (p = 0.047). Multivariate cox-regression demonstrated that abnormal RVFWLS is independently associated with 30-day mortality (Hazard-Ratio 2.22 [1.14–4.39], p = 0.020). Conclusions: Abnormal RVFWLS (> −20%) is independently associated with 30-day mortality in patients with COVID-19 undergoing IMV. Strategies to prevent RV dysfunction, and treatment when identified by RVFWLS, may be of therapeutic benefit to these patients. Trial Registration: Retrospectively registered 21st Feb 2021. ClinicalTrials.gov Identifier: NCT04764032.