AimsMany studies evaluated the functional response in post-Covid-19 patients; however, they systematically excluded patients with concomitant acute coronary syndrome (ACS).We evaluated the long-term functional capacity assessed by cardiopulmonary exercise test (CPET) in patients hospitalized for ACS and concomitant SARS-CoV2 infection. The secondary aim was to investigate the functional response in patients with symptoms related to “long COVID-19 syndrome” (LCS). MethodsThis cross-sectional case-control study compared 20 patients with ACS and concomitant SARS-COV2 infection with 20 patients without COVID-19. At the follow-up visit (between 6 and 12 months after revascularization procedure) all patients underwent a CPET. ResultsPatients with previous ACS and concomitant COVID-19 showed a reduced O2 consumption than controls (predicted peak V̇O2 74.00% vs 86.70%; p = 0.01) with a high degree of ventilatory inefficiency (VE/ V̇CO2 slope 38.04 vs 30.31; p = 0.002).50% of subjects with previous COVID-19 disease showed symptoms related to “LCS”; this subgroup demarcates the characteristic reduced exercise capacity found in the entire COVID + group. ConclusionsThis study is the first in literature having analyzed the long-term functional capacity phenotype in a population of ACS patients and concomitant SARS-CoV2 infection. Severe ventilatory inefficiency emerged as the functional signature of these patients. Moreover, the subset of patients with symptoms related to LCS has the most compromised long term reduced exercise capacity and an altered ventilation control.