Cardiac function is normal in most patients recovered from COVID-19

Background

There are conflicting results regarding impaired cardiac function in patients that have recovered from COVID-19. Cardiovascular magnetic resonance (CMR) studies have revealed a very high frequency of cardiac involvement (78%) and ongoing myocardial inflammation (60%) in patients recently recovered from COVID-19. Findings are advocating further investigation of the long-term myocardial consequences of COVID-19 disease.

Purpose

We aimed to investigate left ventricular (LV) and right ventricular (RV) function by a comprehensive echocardiographic study in patients recovered from COVID-19 infection 3 months after admission to hospital.

Methods

All patients (n=92) had been hospitalized for COVID-19 and were examined with echocardiography three months after hospitalization. They were 59±13 years, and 43% were women. LV function was assessed by ejection fraction (EF) and global longitudinal strain (GLS) and RV function was measured by fractional area change (FAC), tricuspid annular plane systolic excursion (TAPSE) and RV GLS free wall. Tricuspid regurgitation pressure gradient was measured to estimate pulmonary artery pressure.

Results

LV EF was 63±6% and LV GLS was −18.6±2.2%. All patients had normal EF >53%, but 10 showed signs of subtle impaired LV function by LV GLS (≥ −16%). Only two of these did not have hypertension, LV hypertrophy, diabetes or other preexisting diagnosis of heart disease explaining subtle LV dysfunction. All had normal RV FAC (48±7%) and TAPSE (2.3±0.3 cm). We found modestly impaired RV longitudinal function (RV GLS free wall >−25%) in 30% patients, but none had RV GLS worse than −20%. One-third of all patients with reduced RV GLS had signs of elevated pulmonary arterial pressures, which might impact the assessment of RV function.

Conclusions

Traditional echocardiographic parameters showed normal function in all hospitalized COVID-19 patients three months after hospital admittance. Approximately one-third had subtle ventricular dysfunction detected by sensitive echocardiographic methods, but these findings could mostly be explained by systemic or pulmonary hypertension. We cannot, however, exclude that a slight reduction in cardiac function in a minority of our patients was caused by the COVID-19 infection.

Funding Acknowledgement

Type of funding sources: Public hospital(s). Main funding source(s): National Clinical Therapy Research in the Specialist Health Services, Norway

Enhanced metabolism of halogenated hydrocarbons in transgenic plants containing mammalian cytochrome P450 2E1

Chlorinated solvents, especially trichloroethylene (TCE), are the most widespread groundwater contaminants in the United States. Existing methods of pumping and treating are expensive and laborious. Phytoremediation, the use of plants for remediation of soil and groundwater pollution, is less expensive and has low maintenance; however, it requires large land areas and there are a limited number of suitable plants that are known to combine adaptation to a particular environment with efficient metabolism of the contaminant. In this work, we have engineered plants with a profound increase in metabolism of the most common contaminant, TCE, by introducing the mammalian cytochrome P450 2E1. This enzyme oxidizes a wide range of important pollutants, including TCE, ethylene dibromide, carbon tetrachloride, chloroform, and vinyl chloride. The transgenic plants had a dramatic enhancement in metabolism of TCE of up to 640-fold as compared with null vector control plants. The transgenic plants also showed an increased uptake and debromination of ethylene dibromide. Therefore, transgenic plants with this enzyme could be used for more efficient remediation of many sites contaminated with halogenated hydrocarbons.