key: cord-254465-y8n7t8rx
authors: Soulat-Dufour, Laurie; Lang, Sylvie; Ederhy, Stephane; Adavane-Scheuble, Saroumadi; Chauvet-Droit, Marion; Nhan, Pascal; Jean, Marie-Liesse; Said, Rim Ben; Issaurat, Pauline; Boccara, Franck; Cohen, Ariel
title: Left ventricular ejection fraction: an additional risk marker in COVID-19
date: 2020-10-19
journal: Arch Cardiovasc Dis
DOI: 10.1016/j.acvd.2020.08.002
sha: 
doc_id: 254465
cord_uid: y8n7t8rx

nan

J o u r n a l P r e -p r o o f Early identification of patients at high risk of death from COVID-19 [1] is a major issue for the management of patient flow and allocation of healthcare resources. Myocardial involvement has been highlighted as a powerful marker of increased hospital morbimortality in these patients [2] , but the role of left ventricular function has not been fully investigated.

On 31 March 2020, our cardiology intensive care unit transitioned into a COVID-19 intensive care unit.

Data from 39 consecutive patients admitted for acute pneumonia caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) who had two-dimensional echocardiography performed on the day of admission were retrospectively analysed. Transthoracic echocardiography examinations were conducted respecting all protection rules and precautions [3] , and the recordings were analysed completely off-line. Patients were divided into those who were intubated or died (n = 12) and those who did not experience an event (survivors without intubation) (n = 27) during the 15 days after admission.

Mean age of the global population was 62 ± 14 years, 27 (69.2%) were men and median oxygen rate at admission was 6 L/min. Median time between admission to the intensive care unit and intubation/death was 5 days. Over 15 days of follow-up, 7 (17.9%) patients needed to be intubated and 7 patients (17.9%) died, for a total of 12 (30.8%) endpoint events (intubations and/or deaths). The clinical, biological and echocardiographic characteristics of patients in the overall population and according to clinical outcome are displayed in the Table. At admission to intensive care, patients who underwent intubation or died, compared with survivors, had a significantly higher respiratory rate, lower haemoglobin level, higher Creactive protein concentration, higher peak concentrations of cardiac biomarkers (high-sensitivity cardiac troponin and B-type natriuretic peptide), and lower left ventricular ejection fraction (all P < 0.05) (Table) .

Kaplan-Meier analysis ( Figure) precautions were used during each echocardiogram examination. Second, our study population was relatively young and had a high risk of complications (median oxygen rate was 6 L/min and respiratory rate was 25 breaths/min). Our results could have been different in a low-risk population (outpatients or non-intensive care unit management).

In the literature, left ventricular dysfunction has been reported in some cases of myocarditis and takotsubo syndrome. A recent study showed that right ventricular function evaluated using strain imaging in a population of patients with COVID-19 with no history of cardiomyopathy was associated with a poorer prognosis [4] . Cardiac injury secondary to COVID-19 appears to be multifactorial. Some authors speculated on the mechanism through angiotensin converting enzyme 2 receptors, inflammatory overreaction, vascular injury (microangiopathy, myocardial infarction), or cytokine storm [5] . So far, the difference between an acute myocardial injury directly linked with COVID-19 or an expression of an unknown atherothrombotic myocardial injury in a population with a high cardiovascular risk remains difficult.

Beyond the complexity of the mechanisms of cardiac involvement in patients with SARS-CoV-2 pneumonia, the non-invasive evaluation of left ventricular function, while respecting protection rules and precautions, could be a simple parameter to refine their short-term prognosis. 

Association of Cardiac Injury With Mortality in Hospitalized Patients With COVID-19 in

Recommendations for Echocardiography Laboratories Participating in Cardiac Point of Care Cardiac Ultrasound (POCUS) and Critical Care Echocardiography Training: Report from the American Society of Echocardiography

Prognostic Value of Right Ventricular Longitudinal Strain in Patients With COVID-19

COVID-19 and the cardiovascular system