Background and Aims

Dyspnea is reported in 20-30% and chest pain and palpitations in 16% of patients after COVID-19. Impaired left ventricular (LV) function could contribute to persistent symptoms and reduced performance. Athletes can also be affected despite a normally good state of health and training. LV function can be studied by speckle tracking echocardiography (STE) in addition to conventional echocardiographic indices. This study aimed to determine the differences in global longitudinal LV strain (GLS) between athletes who had no history of LV dysfunction but had a previous positive COVID-19 test (PCAt) and healthy control athletes (CON). We then investigated whether there was an association between GLS with initial symptoms during COVID-19.

Methods

Transthoracic echocardiography and STE were performed in 88 PCAt (35.2% women) at a median of 2.00 months after SARS-CoV-2 infection and in 52 national squad team CONs (38.5% women). GLS was determined in four-chamber, two-chamber and three-chamber views in the apical, middle, and basal segments. Images were analyzed offline by a blinded examiner using post-processing software (Image Arena, TOMTEC, Germany). Questionnaires on initial symptoms during COVID-19 were evaluated from 57 infected athletes. Statistical analysis was performed using Student`s t-test, unpaired Wilcoxon-Test as well as correlation and regression analyses. 

Results

PCAt showed significantly lower left ventricular global longitudinal strain values compared to CON (LV-GLS -18.39 ± 1.98% vs. -19.87 ± 1.29%, t(136.67) = 5.36, p < 0.010) and normal but reduced diastolic function (E/A 1.55 ± 0.53vs. 1.66 ± 0.42, p = 0.032; E`l 0.15 ± 0.04 vs. 0.17 ± 0.04, p = 0.017; E/E´l 5.70 ± 1.72 vs. 5.27 ± 1.40, p = 0.048). The extent of GLS reduction was closely related to E/A-Ratio (p < 0.010). There was no association between GLS and initial symptoms such as fever (p = 0.774), resting dyspnea (p = 0.622), exertional dyspnea (p = 0.791), palpitations (p = 0.367), chest pain (p = 0.791), or increased resting heart rate (p = 0.758). However, there was a trend in subjectively perceived performance limitation (p = 0.054) and sore throat (p = 0.058). GLS did not correlate with exertional dyspnea existing after COVID-19 (p = 0.385).

Conclusions

Our results showed reduced but normal GLS in athletes after COVID-19 compared with uninfected controls. Diastolic function was also normal but slightly reduced in athletes after COVID-19. This suggests mild myocardial dysfunction after COVID-19, potentially contributing to dyspnea, chest pain, and palpitations, as well as decreased exercise capacity. Follow-up studies and long-term observations in athletes as well as in the general population are needed to evaluate our results.