We thank Dr Miglis and colleagues for their interest in our research.1 We agree with their premise that the prevalence of postural orthostatic tachycardia syndrome (POTS) may be underestimated in our study, as alluded to in our discussion section. Patients we categorized as having provoked orthostatic intolerance (POI) were all improving symptomatically at the time of head-up tilt table (HUTT), and may have demonstrated a true POTS pattern had they been studied earlier in their postacute sequela of COVID-19 (PASC) course. We also recognize other factors identified by the authors that may have contributed to an inaccurate estimation of POTS prevalence: underestimation by using symptoms in the diagnostic HUTT criteria and overestimation by potentially preselecting those with the greatest likelihood of orthostatic intolerance (OI). The objective of our small, single-site study, however, was to characterize the OI seen in PASC rather than define the prevalence of the various subgroups analyzed.
Our decision to continue beta-blockers, as discussed in our study limitations section, was considered. Nearly all of our patients on beta-blockers were previously beta-blocker naive and all had debilitating PASC symptoms that resulted in subjective improvement with medication. As such, we decided to accept the potential influence of beta-blocker continuation on HUTT findings. Regardless, we agree with Dr Miglis and colleagues that some of the one-third of POI patients on beta-blockers at the time of HUTT could potentially have demonstrated a true POTS response had beta-blockers been held.
As to POI, we sought to describe a result seen with some frequency during the provocative component of HUTT. We agree with Dr Miglis and colleagues that additional work is needed to investigate the prevalence of POI response in a broader population and that continuous rather than fixed interval blood pressure and heart rate measurements may be advantageous, describing both in our study limitations section. We are most grateful to Dr Miglis and colleagues for their thoughtful comments, and welcome continued investigation of autonomic function in PASC.
Footnotes
The authors have reported that they have no relationships relevant to the contents of this paper to disclose.
The authors attest they are in compliance with human studies committees and animal welfare regulations of the authors’ institutions and Food and Drug Administration guidelines, including patient consent where appropriate. For more information, visit the Author Center.
Reference
- 1.Jamal S.M., Landers D.B., Hollenberg S.M., et al. Prospective evaluation of autonomic dysfunction in post-acute sequela of COVID-19. J Am Coll Cardiol. 2022;79(79):2325–2330. doi: 10.1016/j.jacc.2022.03.357. [DOI] [PMC free article] [PubMed] [Google Scholar]