ABSTRACT
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.
ABSTRACT
Abstract Aims We continuously monitored right ventricular pressures and the estimated diastolic pulmonary artery pressure (ePAD) for up to 30 days in mechanically ventilated patients with severe COVID-19 acute respiratory distress syndrome in order to detect and treat right ventricular and pulmonary artery hypertension. Methods and Results We retrospectively evaluated right ventricular pressures and the ePAD measured in 30 invasively ventilated COVID-19 acute respiratory distress syndrome patients between 1 October 2020 and 31 March 2021. We divided the patients into two groups, survivors and non-survivors based on their 60 day mortality. Primary outcome variables were the values of right ventricular pressures and the ePAD over time after insertion of the right ventricular probe. Right ventricular systolic pressure [RVSP, (IQR;25th to 75th percentile)] was significantly lower on the first and the last measurement day in the survivors compared with the non-survivors [Day 1: 38 (27?45) vs. 46 (44?49), P = 0.036;last day: 36 (27?44) vs. 51 (40?57) mmHg, P = 0.006]. 16/22 survivors and 7/8 non-survivors received sildenafil orally, one survivor received additionally inhaled nitric oxide and one survivor and one non-survivor each inhaled iloprost. On the last measurement day, both right ventricular pressure amplitude [31 (26?37) vs. 38 (35?47) mmHg, P = 0.027] and ePAD [22 (16?26) vs. 31 (23?34) mmHg, P = 0.043] were significantly lower in the survivors compared with the non-survivors. Four patients in the survivor group developed excessive high RVSP in the course of their disease (peak: 57/61/78/105 mmHg). After sildenafil 20 mg every 8 h, additional inhaled nitric oxide (20 ppm) in one and additional inhaled iloprost 20 ?g every 4 h in another patient RVSP consecutively decreased substantially in all four patients until the end of the measurement period (47/23/42/47 mmHg). Conclusions The RVSP and right ventricular pressure amplitude both were significantly lower in the survivors compared with those in the non-survivors with a significant decrease in RVSP over time in the survivors suggesting successful lowering by pulmonary vasodilators. The ePAD as an indicator of left heart failure was significantly higher in non-survivors compared to the surviving patients.