Right ventricular (RV) dysfunction is a common complication in patients with acute respiratory distress syndrome (ARDS) occurring in 22% to 50% of patients.1 RV dysfunction in the context of ARDS is attributed to increased pulmonary vascular resistance and is associated with increased mortality in patients with ARDS even when lung protective ventilation strategies are employed.1, 2, 3 Severe COVID-19 is characterized by ARDS and respiratory failure of varying severity.4 , 5 In patients with COVID-19, RV dysfunction was found in 39% of 100 consecutively hospitalized patients on echocardiograms performed within 24 hours of hospital admission.6 Although RV dysfunction is reportedly common in patients with COVID-19,6 , 7 whether it is associated with worse outcomes is unknown.
We reviewed medical records of patients admitted to the intensive care unit for COVID-19 at 2 hospitals (University of Michigan, Ann Arbor, Michigan [n = 286] and Hackensack University Medical Center, Hackensack, New Jersey [n = 359]) between March 1, 2020 and April 25, 2020. We identified 282 patients who required mechanical ventilation and had an echocardiogram performed during their hospitalization. Data abstracted from echocardiogram reports included the summary description of RV size and systolic function, tricuspid annular plane systolic excursion, and estimated RV systolic pressure in addition to left ventricular ejection fraction. We compared clinical characteristics and outcomes between patients with and without evidence of RV dysfunction using the t test or Mann–Whitney U test for continuous variables and the chi-square or Fischer's exact test for categoric variables. Two-tailed p ≤0.05 were considered statistically significant. Analyses were performed using SPSS 24 (IBM, New York, New York). The institutional review board at each institution approved this research and waived the requirement for informed consent.
Overall, the mean age of the cohort was 62 (SD 13) and included 183 men (64.9%). Of the 282 hospitalized patients for COVID-19 who were mechanically ventilated and had an echocardiogram, 61 had evidence of at least mild RV dysfunction (21.6%) (Table 1 ). Only 6 patients (2.1%) showed signs of severe RV dysfunction. Patients with signs of RV dysfunction were more likely to have a history of congestive heart failure (16.4% vs 3.6%, p <0.001) and have a lower body mass index but otherwise had no significant differences in clinical characteristics compared with patients without RV dysfunction. There was no statistically significant difference in the incidence of acute kidney injury requiring renal replacement therapy in patients with RV dysfunction (6.6%) compared with those without RV dysfunction (9.5%, p = 0.47). Most importantly, in-hospital mortality was similar between patients with and without RV dysfunction (62.3% compared with 59.7%, respectively; p = 0.72). Among patients with abnormal RV function who died (n = 38), only 4 (10.5%) had severe RV dysfunction.
Table 1.
Characteristics of patients who developed RV dysfunction
| RV Dysfunction |
||||
|---|---|---|---|---|
| Variable | Yes (N = 61) |
No (N = 221) |
P-Value | |
| Baseline Demographics | ||||
| Age (years) – mean (SD) | 64 (±12) | 62 (±14) | 0.49 | |
| Male sex – no. | 39 (63.9%) | 144 (65.2%) | 0.86 | |
| Black – no. | 12 (19.7%) | 26 (11.8%) | 0.23 | |
| Body mass index (kg/m2) – mean (SD) | 30 (±7) | 32 (±8) | 0.06 | |
| Body mass index (kg/m2) – no. | ||||
| <30 | 33 (55.0%) | 82 (37.8%) | 0.017 | |
| 30-34 | 14 (23.3%) | 56 (25.8%) | ||
| 35-39 | 7 (11.7%) | 43 (19.8%) | ||
| ≥40 | 6 (10.0%) | 36 (16.6%) | ||
| Coexisting Conditions – no. | ||||
| Smoking history | 17 (27.9%) | 65 (29.4%) | 0.48 | |
| Diabetes mellitus | 30 (49.2%) | 91 (41.2%) | 0.26 | |
| Hypertension | 41 (67.2%) | 135 (61.1%) | 0.38 | |
| Coronary artery disease | 12 (19.7%) | 32 (14.5%) | 0.32 | |
| Congestive heart failure | 10 (16.4%) | 8 (3.6%) | <0.001 | |
| Hospital admission eGFR – mean (SD) | 60 (±33) | 67 (±30) | 0.12 | |
| Echocardiographic Parameters | ||||
| LVEF, % - mean (SD) | 59 (±18) | 59 (±14) | 0.92 | |
| LVEF <45%, - no. | 3 (18.8%) | 10 (18.2%) | 0.96 | |
| RV systolic function – no. | <0.001 | |||
| Normal | 0 (0.0%) | 218 (100.0%) | - | |
| Mildly decreased | 44 (72.1%) | 0 (0.0%) | ||
| Moderately decreased | 11 (18.0%) | 0 (0.0%) | ||
| Severely decreased | 6 (9.8%) | 0 (0.0%) | ||
| RV dilation – no. | <0.001 | |||
| None | 34 (57.6%) | 160 (86.5%) | - | |
| Mild | 15 (25.4%) | 20 (10.8%) | ||
| Moderate | 9 (15.3%) | 3 (1.6%) | ||
| Severely decreased | 1 (1.7%) | 2 (1.1%) | ||
| TAPSE, mm – mean (SD) | 15 (±2) | 21 (±3) | <0.001 | |
| RVSP, mmHg – mean (SD) | 42 (±15) | 37 (±14) | 0.06 | |
| Outcomes – no (%) | ||||
| AKI requiring renal replacement therapy | 4 (6.6%) | 21 (9.5%) | 0.47 | |
| In-hospital mortality | 38 (62.3%) | 132 (59.7%) | 0.72 | |
Abbreviations: AKI, acute kidney injury, eGFR, estimated glomerular filtration rate, LVEF, left ventricular systolic ejection fraction, RV, right ventricle, SD, standard deviation, TAPSE, tricuspid annular plane systolic excursion
Little is known about the incidence and outcomes of RV dysfunction in critically ill patients with COVID-19. A prospective cohort of 1,216 patients from 69 countries found 33% of patients with suspected or confirmed COVID-19 had echocardiographic evidence of RV dysfunction but did not report whether RV dysfunction impacted outcomes.7 In another study of 100 consecutive patients hospitalized for COVID-19 who underwent echocardiography within 24 hours of admission, both RV dysfunction and left ventricular dysfunction were common (39% and 16%, respectively).6 Sequential echocardiograms in 20 patients with clinical deterioration revealed worsening of RV function indexes; however, the association with in-hospital mortality was also not reported.6
Our estimate of the incidence of RV dysfunction in patients with COVID–19-related respiratory failure (21.6%) is similar to that previously reported in patients with ARDS with or without COVID-19.1 The mechanism of RV dysfunction is likely independent of the specific viral illness and related to hypoxic vasoconstriction of the pulmonary vasculature, increased positive end-expiratory pressure, hypercapnia, and acidosis.1 We found RV dysfunction was not a major determinant of in-hospital mortality, despite the selection of a high-risk population and a reported mortality of over 50%. The lack of an association may be related to the low number of patients with severe RV dysfunction. Accurate assessment or RV function is also challenging with echocardiography, and other functional monitoring systems may provide a more precise picture of the overall health of the RV, as was used in the Fluids and Catheters Treatment Trial, for example, to determine the increased mortality burden of RV dysfunction.3
Our study has limitations, the most important being the lack of systematic echocardiographic evaluation, lending a risk of selection bias and potential overestimation of RV dysfunction. The echocardiographic imaging of the RV is often challenging, especially in the setting of mechanical ventilation, which could have impacted the accuracy of RV function assessment.
Overall, the incidence of RV dysfunction in patients with COVID–19-related critical illness is similar to that seen in patients with non–COVID-19 ARDS and is not a marker of worse outcomes in this setting.
Author Contributions
Samantha K. Brenner and Salim S. Hayek conceived of the study design and had access to all of the source data. SSH conducted the statistical analysis. Samantha K. Brenner and Salim S. Hayek created the tables and drafted the article. All authors contributed to data collection, critically reviewed the article, and provided substantive feedback.
Declaration of Competing Interest
The authors have no conflicts of interest to declare.
References
- 1.Zochios V, Parhar K, Tunnicliffe W, Roscoe A, Gao F. The right ventricle in ARDS. Chest. 2017;152:181–193. doi: 10.1016/j.chest.2017.02.019. [DOI] [PubMed] [Google Scholar]
- 2.Mekontso Dessap A, Boissier F, Charron C, Bégot E, Repessé X, Legras A, Brun-Buisson C, Vignon P, Vieillard-Baron A. Acute cor pulmonale during protective ventilation for acute respiratory distress syndrome: prevalence, predictors, and clinical impact. Intensive Care Med. 2016;42:862–870. doi: 10.1007/s00134-015-4141-2. [DOI] [PubMed] [Google Scholar]
- 3.Bull TM, Clark B, McFann K, Moss M. National Institutes of Health/National Heart, Lung, and Blood Institute ARDS Network. Pulmonary vascular dysfunction is associated with poor outcomes in patients with acute lung injury. Am J Respir Crit Care Med. 2010;182:1123–1128. doi: 10.1164/rccm.201002-0250OC. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 4.Gupta S, Hayek SS, Wang W, Chan L, Mathews KS, Melamed ML, Brenner SK, Leonberg-Yoo A, Schenck EJ, Radbel J, Reiser J, Bansal A, Srivastava A, Zhou Y, Sutherland A, Green A, Shehata AM, Goyal N, Vijayan A, Velez JCQ, Shaefi S, Parikh CR, Arunthamakun J, Athavale AM, Friedman AN, Short SAP, Kibbelaar ZA, Abu Omar S, Admon AJ, Donnelly JP, Gershengorn HB, Hernán MA, Semler MW, Leaf DE. STOP-COVID Investigators. Factors associated with death in critically ill patients with coronavirus disease 2019 in the US [published correction appears in JAMA Intern Med 2020;180:1555] [published correction appears in JAMA Intern Med 2021;181:1144] JAMA Intern Med. 2020;180:1436–1447. doi: 10.1001/jamainternmed.2020.3596. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 5.Wang Y, Lu X, Li Y, Chen H, Chen T, Su N, Huang F, Zhou J, Zhang B, Yan F, Wang J. Clinical course and outcomes of 344 intensive care patients with COVID-19. Am J Respir Crit Care Med. 2020;201:1430–1434. doi: 10.1164/rccm.202003-0736LE. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 6.Szekely Y, Lichter Y, Taieb P, Banai A, Hochstadt A, Merdler I, Gal Oz A, Rothschild E, Baruch G, Peri Y, Arbel Y, Topilsky Y. Spectrum of cardiac manifestations in COVID-19: a systematic echocardiographic study. Circulation. 2020;142:342–353. doi: 10.1161/CIRCULATIONAHA.120.047971. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 7.Dweck MR, Bularga A, Hahn RT, Bing R, Lee KK, Chapman AR, White A, Salvo GD, Sade LE, Pearce K, Newby DE, Popescu BA, Donal E, Cosyns B, Edvardsen T, Mills NL, Haugaa K. Global evaluation of echocardiography in patients with COVID-19. Eur Heart J Cardiovasc Imaging. 2020;21:949–958. doi: 10.1016/j.amjcard.2022.01.004. https://doi.org/ [DOI] [PMC free article] [PubMed] [Google Scholar]