| Recruiting | 2 | 380 | US | IVIG + Coordinated Care, IVIG Placebo + Coordinated Care, Ivabradine + Coordinated Care, Ivabradine Placebo + Coordinated Care, IVIG + Usual Care, IVIG Placebo + Usual Care, Ivabradine + Usual Care, Ivabradine Placebo + Usual Care | Kanecia Obie Zimmerman | Long COVID, Long Covid19, Long Covid-19 | 12/25 | 03/26 | | |