RECOVER-AUTONOMIC: Platform Protocol, Appendix B (Ivabradine)
This study is a platform protocol designed to be flexible so that it is suitable for a wide range of settings within health care systems and in community settings where it can be integrated into COVID-19 programs and subsequent treatment plans.

This protocol is a prospective, multi-center, multi-arm, randomized, controlled platform trial evaluating various interventions for use in the treatment of autonomic dysfunction symptoms, including cardiovascular complications and postural orthostatic tachycardia syndrome (POTS), in PASC participants. The interventions tested will include non-pharmacologic care and pharmacologic therapies with study drugs.
- EligibilityCriteria: Inclusion Criteria:  See NCT######## for RECOVER-AUTO: Platform Protocol level inclusion criteria which applies to this appendix (or sub-study)  Additional Appendix B (Ivabradine Sub-study) Level Inclusion Criteria:  Abnormal active standing test defined as presence of orthostatic tachycardia (an increase of 30 beats per minute (bpm) or more in HR within 10 minutes upon standing without orthostatic hypotension) and experiencing orthostatic symptoms COMPASS-31 Score > 25 and not enrolled in the IVIG appendix  Exclusions Criteria:  See NCT######## for RECOVER-AUTO: Platform Protocol level inclusion criteria which applies to this appendix (or sub-study)  Additional Appendix B (Ivabradine Sub-study) Level Exclusion Criteria:  A person of child-bearing potential who is not taking effective contraception Use of the following medications: clonidine, tizanidine, amphetamines, and serotonin and norepinephrine reuptake inhibitors (SNRIs) with the exception of modafinil Use of beta-blockers (any formulation), calcium channel blockers, midodrine, pyridostigmine, fludrocortisone, and guanfacine will be excluded unless participant is on a stable dose (>4 weeks). Participants on stable doses will be allowed to continue the medication throughout the study. Combination with verapamil or diltiazem which are moderate CYP3A4 inhibitors with heart rate reducing properties Lactating and breast-feeding women Severe hepatic impairment Use of drugs known to prolong the QT-interval (e.g., quinidine, disopyramide, bepridil, sotalol, amiodarone, pimozide, ziprasidone, sertindole, mefloquine, halofantrine, pentamidine Concomitant use of digoxin Participants who are pacemaker dependent Patients with hypokalemia (serum K+<3.5 mEq/L) Patients taking potassium-depleting diuretics A history of congenital or acquired long QT syndrome, with or without torsade de pointes Patients with high degree AV block such as Mobitz II - HealthyVolunteers: No - Gender: All - MinimumAge: 18 Years - StdAgeList: Adult, Older Adult