LAUSR

Aim: The pulse wave response to salbutamol (PWRS) – change in augmentation index (AIx) – provides a means to assess endothelial vasodilator function in vivo. Endothelial dysfunction plays a relevant role in the pathogenesis of hypertension and cardiovascular disease and appears to underlie many of the complications of coronavirus disease 2019 (COVID-19). However, to what degree this persists after recovery is unknown. Methods: Individuals previously hospitalized with COVID-19, those recovered from mild symptoms and seronegative controls with well known risk factors for endothelial dysfunction were studied. To assess the involvement of nitric oxide-cyclic guanosine monophosphate pathway (NO-cGMP) on PWRS, sildenafil was also administrated in a subsample. Results: One hundred and one participants (60 men) aged 47.8 ± 14.1 (mean ± SD) years of whom 33 were previously hospitalized with COVID-19 were recruited. Salbutamol had minimal effect on haemodynamics including blood pressure and heart rate. It reduced AIx in controls (n = 34) and those recovered from mild symptoms of COVID-19 (n = 34) but produced an increase in AIx in those previously hospitalized: mean change [95% confidence interval] −2.85 [−5.52, −0.188] %, −2.32 [−5.17,0.54] %, and 3.03 [0.06, 6.00] % for controls, those recovered from mild symptoms and those previously hospitalized, respectively (P = 0.001). In a sub-sample (n = 22), sildenafil enhanced PWRS (change in AIx 0.05 [−2.15,2.24] vs. −3.96 [−7.01. −2.18], P = 0.006) with no significant difference between hospitalized (n = 12) and nonhospitalized participants (n = 10). Conclusions: In patients previously hospitalized with COVID-19, there is long-lasting impairment of endothelial function as measured by the salbutamol-induced stimulation of the NO-cGMP pathway that may contribute to cardiovascular complications.