Angiotensin II in ECMO patients: a word of caution

The medical treatment of cardiogenic shock

Cardiogenic shock (CS) is a leading cause of mortality worldwide. CS presentation and management in the current era have been widely depicted in epidemiological studies. Its treatment is codified and relies on medical care and extracorporeal life support (ECLS) in the bridge to recovery, chronic mechanical device therapy, or transplantation. Recent improvements have changed the landscape of CS. The present analysis aims to review current medical treatments of CS in light of recent literature, including addressing excitation-contraction coupling and specific physiology on applied hemodynamics. Inotropism, vasopressor use, and immunomodulation are discussed as pre-clinical and clinical studies have focused on new therapeutic options to improve patient outcomes. Certain underlying conditions of CS, such as hypertrophic or Takotsubo cardiomyopathy, warrant specifically tailored management that will be overviewed in this review.

Angiotensin II for Vasodilatory Hypotension in Patients Requiring Mechanical Circulatory Support

Background: Patients supported on mechanical circulatory support devices experience vasodilatory hypotension due to high surface area exposure to nonbiological and non-endothelialized surfaces. Angiotensin II has been studied in general settings of vasodilatory shock, however concerns exist regarding the use of this vasopressor in patients with pre-existing cardiac failure. The objective of this study was to assess the systemic and central hemodynamic effects of angiotensin II in patients with primary cardiac or respiratory failure requiring treatment with mechanical circulatory support devices. Methods: Multicenter retrospective observational study of adults supported on a mechanical circulatory support device who received angiotensin II for vasodilatory shock. The primary outcome was the intraindividual change from baseline in mean arterial pressure (MAP) and vasopressor dosage after angiotensin II. Results: Fifty patients were included with mechanical circulatory devices that were primarily used for cardiac failure (n = 41) or respiratory failure (n = 9). At angiotensin II initiation, the norepinephrine equivalent vasopressor dosage was 0.44 (0.34, 0.64) and 0.47 (0.33, 0.73) mcg/kg/min in the cardiac and respiratory groups, respectively. In the cardiac group, MAP increased from 60 to 70 mmHg (intraindividual P < .001) in the 1 h after angiotensin II initiation and the vasopressor dosage declined by 0.04 mcg/kg/min (intraindividual P < .001). By 12 h, the vasopressor dosage declined by 0.16 mcg/kg/min ( P = .001). There were no significant changes in cardiac index or mean pulmonary artery pressure throughout the 12 h following angiotensin II. In the respiratory group, similar but nonsignificant effects at 1 h on MAP (61-81 mmHg, P = .26) and vasopressor dosage (decline by 0.13 mcg/kg/min, P = .06) were observed. Conclusions: In patients requiring mechanical circulatory support for cardiac failure, angiotensin II produced beneficial systemic hemodynamic effects without negatively impacting cardiac function or pulmonary pressures. The systemic hemodynamic effects in those with respiratory failure were nonsignificant due to limited sample size.

Angiotensin II in Patients With Shock on Mechanical Circulatory Support: A Single-Center Retrospective Case Series

OBJECTIVES

To describe angiotensin II (ANGII) use in patients on mechanical circulatory support (MCS). To evaluate the efficacy and safety of ANGII in patients with shock on MCS.

DESIGN

Retrospective cohort study.

SETTING

A single-center, quaternary care academic medical center.

PARTICIPANTS

The study comprised critically ill patients on MCS.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Fourteen patients were included in this retrospective analysis. The median age was 54 years (44.8, 68.3) and 78.6% were men. Six patients were receiving venoarterial extracorporeal membrane oxygenation support, 4 patients were receiving venovenous extracorporeal membrane oxygenation support, and 4 patients were on left ventricular assist devices. Five patients (36%) achieved hemodynamic response to ANGII at 3 hours, defined as a mean arterial pressure (MAP) of ≥65 mmHg or a 10-mmHg increase in MAP with a decrease or no change in total vasopressor dose. Overall, the median MAP increased from 61 mmHg (51, 73) at baseline to 66 mmHg (58, 71) at 3 hours, and the median norepinephrine dose decreased from 0.45 µg/kg/min (0.28, 0.6) at baseline to 0.2 µg/kg/min (0.18, 0.32) at 3 hours. The in-hospital mortality rate was 78.6%. Two patients experienced severe adverse drug events and 1 patient had a sentinel thrombotic event.

CONCLUSIONS

This study suggested that ANGII may provide a salvage treatment option in patients on MCS with refractory vasodilatory shock. There are several safety considerations with the use of ANGII in these patients. Prospective randomized controlled trials are needed to evaluate the safety and efficacy of ANGII in patients on MCS.

COVID-19 and haemodynamic failure: a point of view on mechanisms and treatment

The SARS-CoV-2-related disease has an undoubted impact on the healthcare system. In the treatment of severe COVID-19 cases, the main focus is on respiratory failure. However, available data suggest an important contribution of haemodynamic impairment in the course of this disease. SARS-CoV-2 may affect the circulatory system in various ways that are universal for septic conditions. Nonetheless, unique features of this pathogen, e.g. direct insult leading to myocarditis and renin-angiotensin-aldosterone axis dysregulation, must be taken into account. Although current recommendations on COVID-19 resemble previous septic shock guidelines, special attention to haemodynamic monitoring and treatment is necessary. Regarding treatment, one must take into account the potential profound hypovolaemia of severe COVID-19 patients. Pharmacological cardiovascular support should follow existing guidelines and practice. Interesting concepts of decatecholaminisation and the effect of vasopressors on pulmonary circulation are also presented in this review on COVID-19-related haemodynamic failure.