Understanding the role of left and right ventricular strain assessment in patients hospitalized with COVID-19

Strain Echocardiography in Acute COVID-19 and Post-COVID Syndrome: More than Just a Snapshot

Speckle-tracking echocardiography (STE) has become an established, widely available diagnostic method in the past few years, making its value clear in cases of COVID-19 and the further course of the disease, including post-COVID syndrome. Since the beginning of the pandemic, many studies have been published on the use of STE in this condition, enabling, on the one hand, a better understanding of myocardial involvement in COVID-19 and, on the other, a better identification of risk to patients, although some questions remain unanswered in regard to specific pathomechanisms, especially in post-COVID patients. This review takes a closer look at current findings and potential future developments by summarising the extant data on the use of STE, with a focus on left and right ventricular longitudinal strain.

Oral ketone esters acutely improve myocardial contractility in post-hospitalized COVID-19 patients: A randomized placebo-controlled double-blind crossover study

Background

COVID-19 is associated with subclinical myocardial injury. Exogenous ketone esters acutely improve left myocardial function in healthy participants and patients with heart failure, but the effects have not been investigated in participants previously hospitalized for COVID-19.

Methods

This is a randomized placebo-controlled double-blind crossover study comparing a single oral ketone ester dose of 395 mg/kg with placebo. Fasting participants were randomized to either placebo in the morning and oral ketone ester in the afternoon or vice versa. Echocardiography was performed immediately after intake of the corresponding treatment. Primary outcome was left ventricular ejection fraction (LVEF). Secondary outcomes were absolute global longitudinal strain (GLS), cardiac output and blood oxygen saturation. Linear mixed effects models were used to assess differences.

Results

We included 12 participants previously hospitalized for COVID-19 with a mean (±SD) age of 60 ± 10 years. The mean time from hospitalization was 18 ± 5 months. Oral ketone esters did not increase LVEF between placebo and oral ketone ester [mean difference: -0.7% (95% CI -4.0 to 2.6%), p = 0.66], but increased GLS [1.9% (95% CI: 0.1 to 3.6%), p = 0.04] and cardiac output [1.2 L/min (95% CI: -0.1 to 2.4 L/min), p = 0.07], although non-significant. The differences in GLS remained significant after adjustment for change in heart rate (p = 0.01). There was no difference in blood oxygen saturation. Oral ketone esters increased blood ketones over time (peak level 3.1 ± 4.9 mmol/L, p < 0.01). Ketone esters increased blood insulin, c-peptide, and creatinine, and decreased glucose and FFA (all p ≤ 0.01) but did not affect glucagon, pro-BNP, or troponin I levels (all p > 0.05).

Conclusion

In patients previously hospitalized with COVID-19, a single oral dose of ketone ester had no effect on LVEF, cardiac output or blood oxygen saturation, but increased GLS acutely.

Clinical trial registration

https://clinicaltrials.gov/, identifier NCT04377035.

Echocardiography and Lung Ultrasound in Long COVID and Post-COVID Syndrome, a Review Document of the Austrian Society of Pneumology and the Austrian Society of Ultrasound in Medicine

Lung ultrasound has the potential to enable standardized follow-up without radiation exposure and with lower associated costs in comparison to CT scans. It is a valuable tool to follow up on patients after a COVID-19 infection and evaluate if there is pulmonary fibrosis developing. Echocardiography, including strain imaging, is a proven tool to assess various causes of dyspnea and adds valuable information in the context of long COVID care. Including two-dimensional (2D) strain imaging, a better comprehension of myocardial damage in post-COVID syndrome can be made. Especially 2D strain imaging (left and the right ventricular strain) can provide information about prognosis.

Echocardiography in Coronavirus Disease 2019 Era: A Single Tool for Diagnosis and Prognosis

Coronavirus disease 2019 (COVID-19) is characterized by multi-organ involvement, including respiratory and cardiac events. Echocardiography is widely considered the first-choice tool for the evaluation of cardiac structures and function because of its reproducibility, feasibility, easy to use at bedside, and for good cost-effectiveness. The aim of our literature review is to define the utility of echocardiography in the prediction of prognosis and mortality in COVID-19 patients with mild to critical respiratory illness, with or without known cardiovascular disease. Moreover, we focused our attention on classical echocardiographic parameters and the use of speckle tracking to predict the evolution of respiratory involvement. Finally, we tried to explore the possible relationship between pulmonary disease and cardiac manifestations.

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

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.

Feasibility, Prediction and Association of Right Ventricular Free Wall Longitudinal Strain with 30-Day Mortality in Severe COVID-19 Pneumonia: A Prospective Study

Introduction: Right ventricular (RV) systolic dysfunction (RVsD) is a common complication of coronavirus infection 2019 disease (COVID-19). The right ventricular free wall longitudinal strain parameter (RV-FWLS) is a powerful predictor of mortality. We explored the performance of RVsD parameters for predicting 30-day mortality and the association between RV-FWLS and 30-day mortality. Methods: COVID-19 patients hospitalized at Amiens University Hospital in the critical care unit with transthoracic echocardiography were included. We measured tricuspid annular plane systolic excursion (TAPSE), the RV S’ wave, RV fractional area change (RV-FAC), and RV-FWLS. The diagnostic performance of RVsD parameters as predictors for 30-day mortality was evaluated by the area under the receiver operating characteristic (ROC) curve (AUC). RVsD was defined by an RV-FWLS < 21% to explore the association between RVsD and 30-day mortality. Results: Of the 116 patients included, 20% (n = 23/116) died and 47 had a RVsD. ROC curve analysis showed that RV-FWLS failed to predict 30-day mortality, as did conventional RV parameters (all p > 0.05). TAPSE (21 (19−26) mm vs. 24 (21−27) mm; p = 0.024) and RV-FAC (40 (35−47)% vs. 47 (41−55)%; p = 0.006) were lowered in the RVsD group. In Cox analysis, RVsD was not associated with 30-day mortality (hazard ratio = 1.12, CI 95% (0.49−2.55), p = 0.78). Conclusion: In severe COVID-19 pneumonia, RV-FWLS was not associated with 30-day mortality.

Association between the Right Ventricular Longitudinal Shortening Fraction and Mortality in Acute Respiratory Distress Syndrome Related to COVID-19 Infection: A Prospective Study

Introduction: Right ventricular systolic dysfunction (RVsD) increases acute respiratory distress syndrome mortality in COVID-19 infection (CARDS). The RV longitudinal shortening fraction (RV-LSF) is an angle-independent and automatically calculated speckle-tracking parameter. We explored the association between RV-LSF and 30-day mortality in CARDS patients. Methods: Moderate-to-severe CARDS patients hospitalized at Amiens University Hospital with transesophageal echocardiography performed within 48 h of intensive care unit admission were included. RVsD was defined by an RV-LSF of <20%. The patients were divided into two groups according to the presence of RVsD. Using multivariate Cox regression, clinical and echocardiographic risk factors predicting 30-day mortality were evaluated. Results: Between 28 February 2020 and 1 December 2021, 86 patients were included. A total of 43% (n = 37/86) of the patients showed RVsD and 22% (n = 19/86) of the patients died. RV-LSF was observed in 26 (23.1−29.7)% of the no-RVsD function group and 16.5 (13.7−19.4)% (p < 0.001) of the RVsD group. Cardiogenic shock (n = 7/37 vs. 2/49, p = 0.03) and acute cor pulmonale (n = 18/37 vs. 10/49, p = 0.009) were more frequent in the RVsD group. The 30-day mortality was higher in the RVsD group (15/37 vs. 4/49, p = 0.001). In a multivariable Cox model, RV-LSF was an independent mortality factor (HR 4.45, 95%CI (1.43−13.8), p = 0.01). Conclusion: in a cohort of moderate-to-severe CARDS patients under mechanical ventilation, RVsD defined by the RV-LSF was associated with higher 30-day mortalities.

Point of care echocardiography and lung ultrasound in critically ill patients with COVID-19

Hundreds of millions got infected, and millions have died worldwide and still the number of cases is rising.Chest radiographs and computed tomography (CT) are useful for imaging the lung but their use in infectious diseases is limited due to hygiene and availability.Lung ultrasound has been shown to be useful in the context of the pandemic, providing clinicians with valuable insights and helping identify complications such as pleural effusion in heart failure or bacterial superinfections. Moreover, lung ultrasound is useful for identifying possible complications of procedures, in particular, pneumothorax.Associations between coronavirus disease 2019 (COVID-19) and cardiac complications, such as acute myocardial infarction and myocarditis, have been reported. As such, point of care echocardiography as well as a comprehensive approach in later stages of the disease provide important information for optimally diagnosing and treating complications of COVID-19.In our experience, lung ultrasound in combination with echocardiography, has a great impact on treatment decisions. In the acute state as well as in the follow-up setting after a severe or critical state of COVID-19, ultrasound can be of great impact to monitor the progression and regression of disease.