Feasibility and Cognitive Benefits of Enhanced External Counterpulsation in Long COVID Patients with Brain Fog

Background: Long COVID commonly features cognitive “brain fog,” and vascular involvement has been implicated. Enhanced external counterpulsation (EECP), approved for angina and heart failure, may improve cerebral perfusion, but evidence for post-COVID symptoms remains limited. Aim: To evaluate the physiological and psychological effects of EECP in patients with long COVID–related brain fog, focusing on cerebral blood flow (CBF) and symptom severity. Methods: Five adults (≥18 years) with persistent post-COVID brain fog received 15 h of EECP over 8 weeks. Prefrontal cerebral perfusion was assessed using near-infrared spectroscopy (NIRS), and symptoms were measured using the Brain Fog Scale (BFS) at baseline, midpoint, and post-intervention. Correlation analyses and generalized estimating equations (GEE) were performed. Results: All participants completed the protocol. Prefrontal cerebral blood flow increased from baseline to post-intervention, while BFS total scores decreased. EECP exposure correlated positively with cerebral blood flow ( r = 0.342; P = 0.002) and negatively with BFS severity ( r = −0.418; P = 0.001); cerebral blood flow was also inversely correlated with BFS scores ( r = −0.354; P = 0.017). GEE showed significant perfusion increases at the third, fifth, and ninth treatment hours ( P < 0.01), with a borderline BFS-perfusion association ( B = −0.09; P = 0.051). Conclusion: EECP was associated with increased NIRS-derived cerebral perfusion and improved brain fog symptoms in long COVID. Given the small, uncontrolled design, causal inference is limited; larger controlled studies are needed to confirm these preliminary findings.