The Right Ventricle in COVID-19 Lung Injury: Proposed Mechanisms, Management, and Research Gaps

Correlation between worsening pneumonitis and right ventricular systolic function in critically ill patients with COVID-19

BACKGROUND

The pneumonitis associated with coronavirus disease 2019 (COVID-19) infection impacts the right ventricle (RV). However, the association between the disease severity and right ventricular systolic function needs elucidation.

METHOD

We conducted a retrospective study of 108 patients admitted to critical care with COVID-19 pneumonitis to examine the association between tricuspid annular plane systolic excursion (TAPSE) by transthoracic echocardiography as a surrogate for RV systolic function with PaO2/FiO2 ratio as a marker of disease severity and other respiratory parameters.

RESULTS

The median age was 59 years [51, 66], 33 (31%) were female, and 63 (58%) were mechanically ventilated. Echocardiography was performed at a median of 3 days [2, 12] following admission to critical care. The PaO2/FiO2 and TAPSE medians were 20.5 [14.4, 32.0] and 21 mm [18, 24]. There was a statistically significant, albeit weak, association between the increase in TAPSE and the worsening of the PaO2/FiO2 ratio (r2 = 0.041, p = 0.04). This association was more pronounced in the mechanically ventilated (r2 = 0.09, p = 0.02). TAPSE did not correlate significantly with FiO2, PaO2, PaCO2, pH, respiratory rate, or mechanical ventilation. Patients with a TAPSE ≥ 17 mm had a considerably worse PaO2/FiO2 ratio than a TAPSE < 17 mm (18.6 vs. 32.1, p = 0.005). The PaO2/FiO2 ratio predicted TAPSE (OR = 0.94, p = 0.004) with good area under the curve (0.72, p = 0.006). Moreover, a PaO2/FiO2 ratio < 26.7 (moderate pneumonitis) predicted TAPSE > 17 mm with reasonable sensitivity (67%) and specificity (68%).

CONCLUSION

In patients admitted to critical care with COVID-19 pneumonitis, TAPSE increased as the disease severity worsened early in the course of the disease, especially in the mechanically ventilated. A TAPSE within the normal range is not necessarily reassuring in early COVID-19 pneumonitis.

Performance of handheld ultrasound devices in diagnosis of pulmonary hypertension and right heart dysfunction in ICU patients

AIM

The use of handheld ultrasonography devices (HHUD) has increased recently but there are limited data about their performance in the evaluation of right heart dysfunction (RHD) and pulmonary hypertension (PHT). The aim of the study is to compare the performance of a HHUD with a conventional ultrasound device (CUD) in assessing PHT and RHD.

METHODS

This single-center prospective study was performed in a seven-bed teaching hospital intensive care unit (ICU). PHT and RHD criteria were compared by HHUD and CUD. Additional PHT criteria and right ventricle (RV) systolic and diastolic dysfunction criteria were also measured.

RESULTS

Forty-six patients were included in the study. There was no significant difference between the imaging rates and mean values of the parameters measured by both devices. When the positivity rates for additional PHT parameters and RHD criteria were compared, there were no significant differences between the devices. In Bland-Altman's analysis, there was good agreement and there was no bias between the measurements of the two devices but left ventricular end-systolic eccentricity index (LVSEI), right atrium area (RAA), and pulmonary artery diameter (PAD). Ninety percent of the patients had PHT probability, of whom 43% had a low, 37% had intermediate and 10% had a high probability of PHT. Ninety-two percent of the patients had RHD and there was no significant difference between the devices in the diagnosis of RHD (p = .212). When RV systolic and diastolic dysfunction evaluations of the devices were compared according to the British Society of Echocardiography (BSE) criteria there was no significant difference between the devices' measurements in the evaluation of systolic and diastolic function.

CONCLUSION

The imaging and measurement capabilities of the HHUDs for PHT and RHD parameters were similar to CUDs, and considering the inconsistent parameters, the HHUD can be useful in diagnosing these problems.

Association between echocardiographic features and inflammatory biomarkers with clinical outcomes in COVID-19 patients in Saudi Arabia

Background

Respiratory infections are one of the most common comorbidities identified in hospitalized patients. The coronavirus disease 2019 (COVID-19) pandemic greatly impacted healthcare systems, including acute cardiac services.

Aim

This study aimed to describe the echocardiographic findings of patients with COVID-19 infections and their correlations with inflammatory biomarkers, disease severity, and clinical outcomes.

Methods

This observational study was conducted between June 2021 and July 2022. The analysis included all patients diagnosed with COVID-19 who had transthoracic echocardiographic (TTE) scans within 72 h of admission.

Results

The enrolled patients had a mean age of 55.6 ± 14.7 years, and 66.1% were male. Of the 490 enrolled patients, 203 (41.4%) were admitted to the intensive care unit (ICU). Pre-ICU TTE findings showed significantly higher incidence right ventricular dysfunction (28 [13.8%] vs. 23 [8.0%]; P = 0.04) and left ventricular (LV) regional wall motion abnormalities (55 [27.1%] vs. 29 [10.1%]; p < 0.001) in ICU patients compared to non-ICU patients. In-hospital mortality was 11 (2.2%), all deaths of ICU patients. The most sensitive predictors of ICU admission (p < 0.05): cardiac troponin I level (area under the curve [AUC] = 0.733), followed by hs-CRP (AUC = 0.620), creatine kinase-MB (AUC = 0.617), D-dimer (AUC = 0.599), and lactate dehydrogenase (AUC = 0.567). Binary logistic regression showed that reduced LV ejection fraction (LVEF), elevated pulmonary artery systolic pressure, and dilated right ventricle were echocardiographic predictors of poor outcomes (p < 0.05).

Conclusion

Echocardiography is a valuable tool in assessing admitted patients with COVID-19. Lower LVEF, pulmonary hypertension, higher D-dimer, C-reactive protein, and B-type natriuretic peptide levels were predictors of poor outcomes.

Right ventricle dysfunction does not predict mortality in patients with SARS-CoV-2-related acute respiratory distress syndrome on extracorporeal membrane oxygenation support

BACKGROUND

The prognostic role of right ventricle dilatation and dysfunction (RVDD) has not been elucidated in patients with coronavirus disease (COVID)-related respiratory failure refractory to standard treatment needing extracorporeal membrane oxygenation (ECMO) support.

AIM

To assess whether pre veno-venous (VV) ECMO RVDD were related to in-intensive care unit (ICU) mortality.

METHODS

We enrolled 61 patients with COVID-related acute respiratory distress syndrome refractory to conventional treatment submitted to VV ECMO and consecutively admitted to our ICU (an ECMO referral center) from 31^th March 2020 to 31^th August 2021. An echocardiographic exam was performed immediately before VV ECMO implantation.

RESULTS

Males were prevalent (73.8%) and patients with a body mass index > 30 kg/m² were the majority (46/61, 75%). The overall in-ICU mortality rate was 54.1% (33/61). RVDD was detectable in more than half of the population (34/61, 55.7%) and associated with higher simplified organ functional assessment (SOFA) values (P = 0.029) and a longer mechanical ventilation duration prior to ECMO support (P = 0.046). Renal replacement therapy was more frequently needed in RVDD patients (P = 0.002). A higher in-ICU mortality (P = 0.024) was observed in RVDD patients. No echo variables were independent predictors of in-ICU death.

CONCLUSION

In patients with COVID-related respiratory failure on ECMO support, RVDD (dilatation and dysfunction) is a common finding and identifies a subset of patients characterized by a more severe disease (as indicated by higher SOFA values and need of renal replacement therapy) and by a higher in-ICU mortality. RVDD (also when considered separately) did not result independently associated with in-ICU mortality in these patients.

Clinical Significance of Right Ventricle Echocardiographic Patterns in Critically-Ill COVID-Related Acute Respiratory Distress Syndrome "On Behalf of Protecting the Right Ventricle Network (PRORVnet)"

We assessed whether right ventricle (RV) alterations and their development may have clinical significance in critically-ill Coronavirus Disease (COVID) patients, as detected by serial echocardiograms during Intensive Care Unit (ICU) course. This observational single center study included 98 consecutive patients with COVID-related acute respiratory distress syndrome (ARDS). Three subgroups were considered: RV Dysfunction (Dys) on admission (10/98, 10%), developed RV Dys (17/98, 17%), and no RV Dys (71/98, 73%). Overall mortality at 3 months was 46.9%. The first subgroup was characterized by the highest need for Extracorporeal Membrane Oxygenation (ECMO) support (P < .001) and a systemic inflammatory activation (as indicated by increased D-dimer), the second one by the lowest PaO2/FiO2 (P/F). At multivariate regression analysis, age and Sequential Organ Failure Assessment score were independent predictors for mortality. Different RV echo patterns were observed in critically ill patients presenting with COVID-related ARDS during ICU stay. RV Dys on admission was characterized by a high inflammatory activation while patients who developed RV Dys during ICU stay showed lowest P/F. Both these two subgroups identify patients with a severe COVID disease which in a high percentage of cases was unresponsive to standard treatment and required the use of ECMO.

Pressure-based beat-to-beat right ventricular ejection fraction and Tau from continuous measured ventricular pressures in COVID-19 ARDS patients

We evaluated pressure-based right ventricular ejection fraction (RVEF) and diastolic isovolumetric relaxation time constant (Tau) from continuously (up to 30 days) invasive measured right ventricular pressures in mechanically ventilated patients with severe COVID-19 acute respiratory distress syndrome (ARDS). We retrospectively calculated beat-to-beat ejection fraction from right ventricular pressures and dp/dt maximum and minimum in 39 patients treated between October 1st, 2020 and June 30th, 2021. After performing a stepwise logistic regression with survival as a dependent variable, we divided the patients into survivors and nonsurvivors based on their 60-day mortality. Independent outcome variables were the values of RVEF and Tau over time after insertion of the right ventricular probe along with right ventricular systolic and diastolic pressures (RVSP) and the estimated pulmonary artery diastolic pressure (ePAD). RVEF increased significantly over time in the survivors (estimate: 0.354; 95% confidence interval, CI: 0.18-0.53; p < 0.001) but remained unchanged in the nonsurvivors. Tau increased significantly in the nonsurvivors (estimate: 0.001; 95% CI: 0.0004-0.0018; p < 0.002) but not in the survivors. On the last measurement day, RVSP and ePAD were significantly lower while RVEF was significantly higher in the survivors compared to the nonsurvivors. In COVID-19 ARDS patient's, calculation of beat-to-beat RVEF and Tau from continuously invasive measured right ventricular pressures seems to unravel contrary trends in RVEF with an increase in the surviving and a decrease in the nonsurviving patients. Tau remained unchanged in the surviving but increased in the nonsurviving patients over time.

Usefulness and limitations of the acute respiratory distress syndrome definitions in non-intubated patients. A narrative review

According to the Berlin Definition of acute respiratory distress syndrome (ARDS), a positive end-expiratory pressure (PEEP) of at least 5 cmH₂O is required to diagnose and grade ARDS. While the Berlin consensus statement specifically acknowledges the role of non-invasive ventilation (NIV) in mild ARDS, this stratification has traditionally presumed a mechanically ventilated patient in the context of moderate to severe ARDS. This may not accurately reflect today's reality of clinical respiratory care. NIV and high-flow nasal cannula oxygen therapy (HFNO) have been used for managing of severe forms of acute hypoxemic respiratory failure with growing frequency, including in patients showing pathophysiological signs of ARDS. This became especially relevant during the COVID-19 pandemic. The levels of PEEP achieved with HFNO have been particularly controversial, and the exact FiO₂ it achieves is subject to variability. Pinpointing the presence of ARDS in patients receiving HNFO and the severity in those receiving NIV therefore remains methodically problematic. This narrative review highlights the evolution of the ARDS definition in the context of non-invasive ventilatory support and provides an overview of the parallel development of definitions and ventilatory management of ARDS. It summarizes the methodology applied in clinical trials to classify ARDS in non-intubated patients and the respective consequences on treatment. As ARDS severity has significant therapeutic and prognostic consequences, and earlier treatment in non-intubated patients may be beneficial, closing this knowledge gap may ultimately be a relevant step to improve comparability in clinical trial design and outcomes.

Cardiac Magnetic Resonance Findings in Patients Recovered from COVID-19 Pneumonia and Presenting with Persistent Cardiac Symptoms: The TRICITY-CMR Trial

The prevalence and clinical consequences of coronavirus disease 2019 (COVID-19)-related non-ischemic cardiac injury are under investigation. The main purpose of this study was to determine the occurrence of non-ischemic cardiac injury using cardiac magnetic resonance (CMR) imaging in patients with persistent cardiac symptoms following recovery from COVID-19 pneumonia. We conducted a single-center, cross-sectional study. Between January 2021 and May 2021, we enrolled 121 patients with a recent COVID-19 infection and persistent cardiac symptoms. Study participants were divided into those who required hospitalization during the acute phase of SARS-CoV-2 infection (n = 58; 47.9%) and those non-hospitalized (n = 63; 52.1%). Non-ischemic cardiac injury (defined as the presence of late gadolinium enhancement (LGE) lesion and/or active myocarditis in CMR) was detected in over half of post-COVID-19 patients (n = 64; 52.9%). LGE lesions were present in 63 (52.1%) and active myocarditis in 10 (8.3%) post-COVID-19 study participants. The majority of LGE lesions were located in the left ventricle at inferior and inferolateral segments at the base. There were no significant differences in the occurrence of LGE lesions (35 (60.3%) vs. 28 (44.4%); p = 0.117) or active myocarditis (6 (10.3%) vs. 4 (6.3%); p = 0.517) between hospitalized and non-hospitalized post-COVID-19 patients. However, CMR imaging revealed lower right ventricular ejection fraction (RVEF; 49.5 (44; 54) vs. 53 (50; 58) %; p = 0.001) and more frequent presence of reduced RVEF (60.3% vs. 33.3%; p = 0.005) in the former subgroup. In conclusion, more than half of our patients presenting with cardiac symptoms after a recent recovery from COVID-19 pneumonia had CMR imaging abnormalities indicating non-ischemic cardiac injury. The most common finding was LGE, while active myocarditis was detected in the minority of patients. CMR imaging abnormalities were observed both in previously hospitalized and non-hospitalized post-COVID-19 patients. Further research is needed to determine the long-term cardiovascular consequences of COVID-19 infection and the optimal management of patients with suspected post-COVID-19 non-ischemic cardiac injury.

Cardiovascular subphenotypes in patients with COVID-19 pneumonitis whose lungs are mechanically ventilated: a single-centre retrospective observational study

Unsupervised clustering methods of transthoracic echocardiography variables have not been used to characterise circulatory failure mechanisms in patients with COVID‐19 pneumonitis. We conducted a retrospective, single‐centre cohort study in ICU patients with COVID‐19 pneumonitis whose lungs were mechanically ventilated and who underwent transthoracic echocardiography between March 2020 and May 2021. We performed latent class analysis of echocardiographic and haemodynamic variables. We characterised the identified subphenotypes by comparing their clinical parameters, treatment responses and 90‐day mortality rates. We included 305 patients with a median (IQR [range]) age 59 (49–66 [16–83]) y. Of these, 219 (72%) were male, 199 (65%) had moderate acute respiratory distress syndrome and 113 (37%) did not survive more than 90 days. Latent class analysis identified three cardiovascular subphenotypes: class 1 (52%; normal right ventricular function); class 2 (31%; right ventricular dilation with mostly preserved systolic function); and class 3 (17%; right ventricular dilation with systolic impairment). The three subphenotypes differed in their clinical characteristics and response to prone ventilation and outcomes, with 90‐day mortality rates of 22%, 42% and 73%, respectively (p < 0.001). We conclude that the identified subphenotypes aligned with right ventricular pathophysiology rather than the accepted definitions of right ventricular dysfunction, and these identified classifications were associated with clinical outcomes.

Persistent Right Ventricle Dilatation in SARS-CoV-2-Related Acute Respiratory Distress Syndrome on Extracorporeal Membrane Oxygenation Support

Objectives

Venovenous extracorporeal membrane oxygenation (ECMO) support may be considered in experienced centers for patients with acute respiratory distress syndrome (ARDS) due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection refractory to conventional treatment. In ECMO patients, echocardiography has emerged as a clinical tool for implantation and clinical management; but to date, little data are available on COVID-related ARDS patients requiring ECMO. The authors assessed the incidence of right ventricular dilatation and dysfunction (RvDys) in patients with COVID-related ARDS requiring ECMO.

Design

Single-center investigation.

Setting

Intensive care unit (ICU).

Participants

A total of 35 patients with COVID-related ARDS requiring ECMO, consecutively admitted to the ICU (March 1, 2020, to February 28, 2021).

Interventions

Serial echocardiographic examinations. RvDys was defined as RV end-diastolic area/LV end-diastolic area >0.6 and tricuspid annular plane excursion <15 mm.

Measurements and Main Results

The incidence of RvDys was 15/35 (42%). RvDys patients underwent ECMO support after a longer period of mechanical ventilation (p = 0.006) and exhibited a higher mortality rate (p = 0.024) than those without RvDys. In nonsurvivors, RvDys was observed in all patients (n = nine) who died with unfavorable progression of COVID-related ARDS. In survivors, weaned from ECMO, a significant reduction in systolic pulmonary arterial pressures was detectable.

Conclusions

According to the authors’ data, in COVID-related ARDS requiring ECMO support, RvDys is common, associated with increased ICU mortality. Overall, the data underscored the clinical role of echocardiography in COVID-related ARDS supported by venovenous ECMO, because serial echocardiographic assessments (especially focused on RV changes) are able to reflect pulmonary COVID disease severity.

Right ventricular dysfunction and right ventricular-arterial uncoupling at admission increase the in-hospital mortality in patients with COVID-19 disease

Background

Coronavirus disease 2019 (COVID‐19) frequently involves cardiovascular manifestations such as right ventricular (RV) dysfunction and alterations in pulmonary hemodynamics. We evaluated the application of the critical care ultrasonography ORACLE protocol to identify the most frequent alterations and their influence on adverse outcomes, especially those involving the RV (dilatation and dysfunction).

Methods

This cross‐sectional study included 204 adult patients with confirmed COVID‐19 admitted at three centers. Echocardiography and lung ultrasound images were acquired on admission using the ORACLE ultrasonography algorithm.

Results

Two‐hundred and four consecutive patients were evaluated: 22 (11.9%) demonstrated a fractional shortening of < 35%; 33 (17.1%) a tricuspid annular plane systolic excursion (TAPSE) of < 17 mm; 26 (13.5%) a tricuspid peak systolic S wave tissue Doppler velocity of < 9.5 cm/sec; 69 (37.5%) a RV basal diameter of > 41 mm; 119 (58.3%) a pulmonary artery systolic pressure (PASP) of > 35 mm Hg; and 14 (11%) a TAPSE/PASP ratio of < .31. The in‐hospital mortality rate was 37.6% (n = 71). Multiple logistic regression modeling showed that PASP > 35 mm Hg, RV FS of < 35%, TAPSE < 17 mm, RV S wave < 9.5, and TAPSE/PASP ratio < .31 mm/mm Hg were associated with this outcome. PASP and the TAPSE/PASP ratio had the lowest feasibility of being obtained among the investigators (62.2%).

Conclusion

The presence of RV dysfunction, pulmonary hypertension, and alteration of the RV–arterial coupling conveys an increased risk of in‐hospital mortality in patients presenting with COVID‐19 upon admission; therefore, searching for these alterations should be routine. These parameters can be obtained quickly and safely with the ORACLE protocol.