Oxygenated right ventricular assist device as part of veno-venopulmonary extracorporeal membrane oxygenation to support the right ventricle and pulmonary vasculature.

COVID-19 infection can lead to severe acute respiratory distress syndrome (ARDS), right ventricular (RV) failure and pulmonary hypertension. Venovenous extracorporeal membrane oxygenation (V-V ECMO) has been used for patients with refractory hypoxemia. More recently dual-lumen right atrium to pulmonary artery oxygenated right ventricular assist devices (Oxy-RVAD) have been utilized in the severe medical refractory COVID ARDS setting. Historically, animal data has demonstrated that high continuous non-pulsatile RVAD flows, leading to unregulated and unprotected circulation through the pulmonary vessels is associated with an increased risk of pulmonary hemorrhage and increased amount of extravascular lung water. These risks are heightened in the setting of ARDS with fragile capillaries, left ventricular (LV) diastolic failure, COVID cardiomyopathy, and anticoagulation. Concurrently, due to infection, tachycardia, and refractory hypoxemia, high V-V ECMO flows to match high cardiac output are often necessary to maintain systemic oxygenation. Increase in cardiac output without a concurrent increase in VV ECMO flow will result in a higher fraction of deoxygenated blood returning to the right heart and therefore resulting in hypoxemia. Several groups have suggested using a RVAD only strategy in COVID ARDS; however, this exposes the patients to the risk of pulmonary hemorrhage. We present one of the first known cases using an RV mechanical support, partial flow pulmonary circulation, oxygenated Veno-venopulmonary (V-VP) strategy resulting in RV recovery, total renal recovery, awake rehabilitation, and recovery.

Diagnosis and treatment of right ventricular dysfunction in patients with COVID-19 on veno-venous extra-corporeal membrane oxygenation.

BACKGROUND: Veno-venous (VV) extracorporeal membrane oxygenation (ECMO) is an effective, but highly resource intensive salvage treatment option in COVID patients with acute respiratory distress syndrome (ARDS). Right ventricular (RV) dysfunction is a known sequelae of COVID-19 induced ARDS, yet there is a paucity of data on the incidence and determinants of RV dysfunction on VV ECMO. We retrospectively examined the determining factors leading to RV failure and means of early identification of this phenomenon in patients on VV ECMO. METHODS: The data was extracted from March 2020 to March 2021 from the regional University of Washington Extracorporeal Life Support database. The inclusion criteria included patients > 18 years of age with diagnosis of COVID-19. All had already been intubated and mechanically ventilated prior to VV ECMO deployment. Univariate analysis was performed to identify risk factors and surrogate markers for RV dysfunction. In addition, we compared outcomes between those with and without RV dysfunction. RESULTS: Of the 33 patients that met inclusion criteria, 14 (42%) had echocardiographic evidence of RV dysfunction, 3 of whom were placed on right ventricular assist device support. Chronic lung disease was an independent risk factor for RV dysfunction (p = 0.0002). RV dysfunction was associated with a six-fold increase in troponin I (0.07 ng/ml vs. 0.44 ng/ml, p = 0.039) and four-fold increase in brain natriuretic peptide (BNP) (158 pg/ml vs. 662 pg/ml, p = 0.037). Deep vein thrombosis (DVT, 21% vs. 43%, p = 0.005) and pulmonary embolism (PE, 11% vs. 21%, p = 0.045) were found to be nearly twice as common in the RV dysfunction group. Total survival rate to hospital discharge was 39%. Data trended towards shorter duration of hospital stay (47 vs. 65.6 days, p = 0.15), shorter duration of ECMO support (21 days vs. 36 days, p = 0.06) and improved survival rate to hospital discharge (42.1% vs. 35.7%, p = 0.47) for those with intact RV function compared to the RV dysfunction group. CONCLUSIONS: RV dysfunction in critically ill patients with COVID-19 pneumonia in common. Trends of troponin I and BNP may be important surrogates for monitoring RV function in patients on VV ECMO. We recommend echocardiographic assessment of the RV on such patients.

Unsupervised machine learning demonstrates the prognostic value of TAPSE/PASP ratio among hospitalized patients with COVID-19.

BACKGROUND: The ratio of tricuspid annular plane systolic excursion (TAPSE) to pulmonary artery systolic pressure (PASP) is a validated index of right ventricular-pulmonary arterial (RV-PA) coupling with prognostic value. We determined the predictive value of TAPSE/PASP ratio and adverse clinical outcomes in hospitalized patients with COVID-19. METHODS: Two hundred and twenty-nine consecutive hospitalized racially/ethnically diverse adults (≥18 years of age) admitted with COVID-19 between March and June 2020 with clinically indicated transthoracic echocardiograms (TTE) that included adequate tricuspid regurgitation (TR) velocities for calculation of PASP were studied. The exposure of interest was impaired RV-PA coupling as assessed by TAPSE/PASP ratio. The primary outcome was in-hospital mortality. Secondary endpoints comprised of ICU admission, incident acute respiratory distress syndrome (ARDS), and systolic heart failure. RESULTS: One hundred and seventy-six patients had both technically adequate TAPSE measurements and measurable TR velocities for analysis. After adjustment for age, sex, BMI, race/ethnicity, diabetes mellitus, and smoking status, log(TAPSE/PASP) had a significantly inverse association with ICU admission (p = 0.015) and death (p = 0.038). ROC analysis showed the optimal cutoff for TAPSE/PASP for death was 0.51 mm mmHg-1 (AUC = 0.68). Unsupervised machine learning identified two groups of echocardiographic function. Of all echocardiographic measures included, TAPSE/PASP ratio was the most significant in predicting in-hospital mortality, further supporting its significance in this cohort. CONCLUSION: Impaired RV-PA coupling, assessed noninvasively via the TAPSE/PASP ratio, was predictive of need for ICU level care and in-hospital mortality in hospitalized patients with COVID-19 suggesting utility of TAPSE/PASP in identification of poor clinical outcomes in this population both by traditional statistical and unsupervised machine learning based methods.

First-in-man successful use of the SPECTRUM percutaneous dual-stage right ventricle and right atrium to pulmonary artery ventricular assist device.

BACKGROUND: Over the past decade, several minimally invasive mechanical support devices have been introduced into clinical practice to support the right ventricle (RV). Percutaneous cannulas are easy to insert, minimally invasive, and treat acute RV failure rapidly. In December 2021, the Food and Drug Administration approved a new 31 French dual lumen single cannula for use as a right ventricular assist device. AIMS: Descirbe the use of the new dual lumen percutaneous right ventricular assist device (RVAD) cannula. MATERIAL AND METHODS: Deployment of the RVAD can be done surgically or percutaneously. This cannula, manufactured by Spectrum, is dual staged. It has inflow ports positioned both in the right atrium (RA) as well as the RV for maximal drainage of the right heart. The distal end of the cannula which includes the outflow port is positioned in the pulmonary artery (PA). RESULTS: Deployment of the Spectrum RVAD can be done percutaneously with transesophageal and flouroscopy guidence. Cannulation requires requisite wire skills in order to navigate into the main pulmonary artery. Utilization of this cannula can be done in acute RV failure secondary to ischemia, post cardiotomy shock, acute respiratory failure or other causes of isolated RV failure. DISCUSSION: The dual stage drainage design optimizes venous drainage as well as limits suck-down events. Theoretically, direct RV decompression also decreases RV dilation and wall tension, and facilitates improved transmural pressure gradient to reduce RV strain. CONCLUSION: Here we describe the first-in-man successful use of the dual-stage RA and RV to PA Spectrum cannula in a patient with severe COVID acute respiratory distress syndrome and acute right ventricular failure, bridged to recovery.

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.

COVID-19 Acute Respiratory Distress Syndrome and Pulmonary Embolism: A Case Report of Nebulized Nitroglycerin and Systemic Thrombolysis For Right Ventricular Failure.

BACKGROUND: Acute respiratory compromise caused by complications of COVID-19, such as acute respiratory distress syndrome (ARDS) or thromboembolic disease, is a complex syndrome with unique challenges in treatment. Management often requires time and intensive care through a multiprofessional, multispecialty approach. Initial management is particularly challenging within the limited-resource environment of the emergency department (ED). The emergency physician's toolbox of treatments with reasonably rapid onset remains limited to respiratory support, prone positioning, steroids, and anticoagulation. CASE REPORT: We present a case of a patient with COVID-19 complicated by ARDS and bilateral pulmonary emboli with severe right ventricular dysfunction and systemic hypotension treated with nebulized nitroglycerin and systemic thrombolytic therapy in the ED. Serial evaluation of right ventricular function using point of care ultrasound over the next 2 h showed improvement of function with both agents as well as improvement in the patient's respiratory rate and work of breathing. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: This case describes a novel use of a widely available medication for patients with COVID-19-induced right ventricular dysfunction. Nebulized nitroglycerin may be an option to improve right ventricular function when other inhaled pulmonary vasodilators are not available in the initial ED setting. © 2021 Elsevier Inc.

Topic-Based, Recent Literature Review on Pulmonary Hypertension.

Pulmonary hypertension is a complex condition but a relatively common manifestation of severe cardiopulmonary disease. By contrast, pulmonary arterial hypertension is uncommon and is more prevalent in young women. To better categorize patients and to guide clinical decision-making, 5 diagnostic groups and associated subgroups characterize the spectrum of disease. A multidisciplinary approach to evaluation and treatment is recommended by published guidelines and often entails referral to a designated pulmonary hypertension center. Several key publications during the last couple of years merit review. The PubMed database was searched for English-language studies and guidelines relating to pulmonary hypertension. The following terms were searched, alone and in combination: pulmonary hypertension, pulmonary arterial hypertension, portopulmonary hypertension, and chronic thromboembolic pulmonary hypertension. The focus was on those publications with new information on evaluation and management of pulmonary hypertension between January 1, 2019, and January 31, 2021. Of the subgroups, 2 were of particular interest for this review: portopulmonary hypertension and chronic thromboembolic pulmonary hypertension. Last, available data on the impact of the coronavirus disease 2019 pandemic and newer treatment agents in early trials were selectively reviewed. The review is therefore intended to serve as a practical, focused review of important topics germane to those clinicians caring for patients with pulmonary hypertension.

Unusually Rapid Development of Pulmonary Hypertension and Right Ventricular Failure after COVID-19 Pneumonia.

COVID-19 is a novel viral disease caused by SARS-CoV-2. The mid- and long-term outcomes have not yet been determined. COVID-19 infection is increasingly being associated with systemic and multi-organ involvement, encompassing cytokine release syndrome and thromboembolic, vascular and cardiac events. The patient described experienced unusually rapid development of pulmonary hypertension (PH) and right ventricular failure after recent severe COVID-19 pneumonia with cytokine release syndrome, which initially was successfully treated with methylprednisolone and tocilizumab. The development of pulmonary hypertension and right ventricular failure - in the absence of emboli on multiple CT angiograms - was most likely caused by progressive pulmonary parenchymal abnormalities combined with microvascular damage of the pulmonary arteries (group III and IV pulmonary hypertension, respectively). To the best of our knowledge, these complications have not previously been described and therefore awareness of PH as a complication of COVID-19 is warranted. LEARNING POINTS: COVID-19 increasingly presents with systemic and multi-organ involvement with vascular, thromboembolic and cardiac events.Patients with severe COVID-19 pneumonia and concomitant cytokine release syndrome may be particularly at risk for the development of secondary pulmonary hypertension and right ventricular failure.Pulmonary hypertension can develop unusually rapidly following COVID-19 pneumonia and probably results from progressive pulmonary interstitial and microvascular abnormalities due to COVID-19.