Evaluation of myocardial work in patients recovered from the severe form of COVID-19

The impact of COVID-19 goes beyond its acute form, and can lead to the persistence of symptoms and the emergence of systemic disorders, defined as Post-Covid or Long-Covid.

Assess the late impact on the cardiorespiratory system of patients recovered from severe Covid.

We performed cross-sectional study that included patients over 18 years of age who recovered from the severe form of COVID-19 after at least 60 days of their discharge. Patients and healthy controls were enrolled to perform transthoracic echocardiography (TTE) and cardiopulmonary exercise testing (CPET).

A total of 52 patients and 24 controls were enrolled. The standard TTE parameters (end diastolic diameters, left ventricular ejection fraction, diastolic function and right ventricular systolic function) showed no difference when compared to the control group. When analyzing the myocardial work, there was a higher Wasted MW (GWW): 135 mmHg% vs 84.5 mmHg% (p=0.002), with lower MW Efficiency (GWE): 94 vs. 96 (p=0.003); as well as lower values of global strain: cases = 18.6% vs. 20.1% (p=0.009). No differences were found in the Constructive MW (GWC) and MW Global Index (GWI). In the CPET data we found lower peak values for the VO2: 24 ml/kg/min vs. 32.75 ml/kg/min (p<0.001); for the Heart Rate: 162 bpm vs. 175 bpm (p<0.001); for the Ventilation: 79.3 L/min vs. 109.85 L/min (p<0.001) and Respiratory Exchange Ratio: 1.12 vs. 1.19 (p=0.004). There was no difference in the maximum load reached, neither in the oxygen pulse values and in the Ve/CO2 slope. In relation to the oxygen kinetics, there was a significant reduction in OUES%: 85% vs. 98% (p=0.03); as well as an extended T½: 112 s vs. 88.5 s (p<0.001); and a slowing of the fall in heart rate in recovery time, as measured by the Heart Rate decay: −17.32 bpm vs. −22.08 bpm (p=0.005).

Patients recovered from the severe form of COVID-19 had higher GWW with lower efficiency (GWE). Such findings, added to changes in oxygen kinetics during exercise, may point to a possible cardiocirculatory mechanism associated with decreased aerobic capacity.

Type of funding sources: None.