Could strain echocardiography help to assess systolic function in critically ill COVID-19 patients?

Past and Present of Point-of-Care Ultrasound (PoCUS): A Narrative Review

This article aims to conduct a literature review to gain insight into point-of-care ultrasound (PoCUS). PoCUS is a rapid, accurate, non-invasive, and radiation-free imaging modality that can be used in stable and unstable patients. PoCUS can be performed parallel to physical examination, resuscitation, and stabilization; repeated exams in critical patients are essential for improving sensitivity. The review highlights how PoCUS, which was initially used to detect free intraperitoneal fluid in trauma patients, has developed into a life-saving diagnostic tool that could be utilized by treating physicians during various stages of diagnosis, resuscitation, operation, and postoperative critical care when managing sick patients. The review also notes the barriers to the widespread uptake of PoCUS in general internal medicine and the recent commercial availability of "pocket" or handheld probes that have made PoCUS more readily available. This review concludes that adopting a focused binary decision-making approach can maximize PoCUS's value in many clinical settings, including emergency departments, intensive care units, and operation theatres. Overall, the review emphasizes the importance of awareness of common indications, limitations, and strengths of this evolving and promising technology to determine its future trajectory: Providing comprehensive PoCUS training within internal medicine curriculums and supporting trainers to do so.

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.

Abnormal Echocardiographic Findings in Hospitalized Patients with Covid-19: A Systematic Review and Meta-analysis

BACKGROUND

Coronavirus disease 2019 (Covid-19) can lead to severe respiratory distress and acute cardiac injury, but it is unclear how often it can cause cardiac dysfunction.

OBJECTIVE

In this systematic review, we aimed to summarize the main echocardiographic findings in patients with Covid-19.

METHODS

We systematically searched in PUBMED, EMBASE, LILACS and Cochrane databases, in addition MedRxiv and Scielo preprints from inception to July 21st, 2021. Studies reporting echocardiographic data in patients with Covid-19 were included. Demographic characteristics, previous cardiovascular disease (CVD), and echocardiographic findings were extracted. We performed a meta-analysis of proportions to estimate the main echocardiographic findings. The level of significance was p < 0.05.

RESULTS

From 11,233 studies, 38 fulfilled inclusion criteria and were included in the meta-analysis. The estimated proportions of left ventricular (LV) systolic dysfunction were 25% (95%CI: 19, 31; I293%), abnormal global longitudinal strain 34% (95% CI 23, 45; I290%), righ ventricular (RV) systolic dysfunction 17% (95%CI 13, 21; I290%), pericardial effusion 17% (95%CI: 9, 26; I297%), and pulmonary hypertension 23% (95%CI: 15, 33, I2 96%). LV systolic dysfunction was directly associated with study-specific prevalence of previous abnormal echocardiogram (p<0.001). The proportion of patients in mechanical ventilation, indicating severity of disease, did not explain the heterogeneity in the proportions of LV dysfunction (p=0.37).

CONCLUSION

Among hospitalized patients with Covid-19, LV dysfunction has been reported in one quarter, with smaller proportions of right ventricular dysfunction, pericardial effusion and pulmonary hypertension. However, there was a higher proportion of LV dysfunction among studies reporting the presence of prior heart disease, which suggests that cardiac dysfunction was mostly pre-existing.

Characteristic Immune Dynamics in COVID-19 Patients with Cardiac Dysfunction

Background: We aimed to explore immune parameters in COVID-19 patients admitted to the intensive care unit (ICU) to identify distinctive features in patients with cardiac injury. Methods: A total of 30 COVID-19 patients >18 years admitted to the ICU were studied on days D1, D3 and D7 after admission. Cardiac function was assessed using speckle-tracking echocardiography (STE). Peripheral blood immunophenotyping, cardiac (pro-BNP; troponin) and inflammatory biomarkers were simultaneously evaluated. Results: Cardiac dysfunction (DYS) was detected by STE in 73% of patients: 40% left ventricle (LV) systolic dysfunction, 60% LV diastolic dysfunction, 37% right ventricle systolic dysfunction. High-sensitivity cardiac troponin (hs-cTn) was detectable in 43.3% of the patients with a median value of 13.00 ng/L. There were no significant differences between DYS and nDYS patients regarding mortality, organ dysfunction, cardiac (including hs-cTn) or inflammatory biomarkers. Patients with DYS showed persistently lower lymphocyte counts (median 896 [661−1837] cells/µL vs. 2141 [924−3306] cells/µL, p = 0.058), activated CD3 (median 85 [66−170] cells/µL vs. 186 [142−259] cells/µL, p = 0.047) and CD4 T cells (median 33 [28−40] cells/µL vs. 63 [48−79] cells/µL, p = 0.005), and higher effector memory T cells (TEM) at baseline (CD4%: 10.9 [6.4−19.2] vs. 5.9 [4.2−12.8], p = 0.025; CD8%: 15.7 [7.9−22.8] vs. 8.1 [7.7−13.7], p = 0.035; CD8 counts: 40 cells/µL [17−61] vs. 10 cells/µL [7−17], p = 0.011) than patients without cardiac dysfunction. Conclusion: Our study suggests an association between the immunological trait and cardiac dysfunction in severe COVID-19 patients.

Transthoracic echocardiography of patients in prone position ventilation during the COVID-19 pandemic: an observational and retrospective study

Mechanical ventilation in prone position is a strategy that increases oxygenation and reduces mortality in severe ARDS. The hemodynamic and cardiovascular assessment of these patients is essential. Transthoracic echocardiography (TTE) is a widely used tool to assess hemodynamics in critical care, but the prone position is thought to limit adequate TTE views and goal-oriented measurements. The aim of this study is to show the feasibility of the hemodynamic assessment by transthoracic echocardiography during prone position ventilation (PPV). This is a retrospective, observational study, carried out in the intensive care unit (ICU) of a tertiary-care center in Buenos Aires, Argentina. We included all the adult patients admitted to the ICU between March 2020 and August 2021 who had a TTE examination in PPV due to ARDS. During the study period, we evaluated by TTE a total of 35 patients requiring PPV. The vast majority of the patients had COVID-19 pneumonia (91.4%). In 33 out of 35 (94.3%) cases, it was able to achieve an adequate apical four chamber view. We assessed qualitatively the systolic function of left ventricle (LV) and right ventricle (RV) in all of the successfully evaluated patients. We measured the RV basal diameter (94.3%), RV/LV ratio (77.1%), tricuspid annular plane systolic excursion (TAPSE) (91.4%), and septal mitral annular plane systolic excursion (MAPSE) (88.5%) in most of them. Also, we quantified the left ventricle outflow tract velocity time integral (LVOT VTI) in a large part (68.5%) of the examinations. Transthoracic echocardiography is a useful tool for the hemodynamic assessment of patients in prone position under mechanical ventilation.

The Right Ventricle in COVID-19

Infection with the novel severe acute respiratory coronavirus-2 (SARS-CoV2) results in COVID-19, a disease primarily affecting the respiratory system to provoke a spectrum of clinical manifestations, the most severe being acute respiratory distress syndrome (ARDS). A significant proportion of COVID-19 patients also develop various cardiac complications, among which dysfunction of the right ventricle (RV) appears particularly common, especially in severe forms of the disease, and which is associated with a dismal prognosis. Echocardiographic studies indeed reveal right ventricular dysfunction in up to 40% of patients, a proportion even greater when the RV is explored with strain imaging echocardiography. The pathophysiological mechanisms of RV dysfunction in COVID-19 include processes increasing the pulmonary vascular hydraulic load and others reducing RV contractility, which precipitate the acute uncoupling of the RV with the pulmonary circulation. Understanding these mechanisms provides the fundamental basis for the adequate therapeutic management of RV dysfunction, which incorporates protective mechanical ventilation, the prevention and treatment of pulmonary vasoconstriction and thrombotic complications, as well as the appropriate management of RV preload and contractility. This comprehensive review provides a detailed update of the evidence of RV dysfunction in COVID-19, its pathophysiological mechanisms, and its therapy.