Our Experience with Using WatchPat® (Itamar Medical, Ltd.), Home Sleep Testing (HST) for the Diagnosis of Sleep Apnea in Advanced Heart Failure Patients

Abstract

IntroductionSleep apnea is widely reported as an independent predictor for the development of heart failure (HF), with a 2.6-fold increase in incidence after adjusting for age, sex, body mass index (BMI) and smoking. The accepted gold standard for sleep apnea diagnosis is polysomnography (PSG); however, access to PSG is limited and more so in the COVID-19 pandemic crisis. WatchPAT Home Sleep Testing (WPHST) has been validated to accurately detect both obstructive (OSA) as well as central sleep apnea (CSA) in the general population. However, to date no studies have reported its use in the advanced HF population.MethodsThis was a single center, retrospective, observational analysis, beginning December of 2019-April 2020. All subjects that screened positive on the STOP-BANG sleep apnea questionnaire and assigned the HST were analyzed.Results62 subjects (HF, LVAD, Orthotopic Heart Transplant [OHT]) were assigned HST. 93% (n=58) completed testing. 77% (n=7/9) of patients with LVAD had testing that was deemed inconclusive, thus patients with LVAD were censored from our analysis. Of the 44 patients that tested positive for at least mild OSA, 32 % (n=14) of the patients were post OHT. Over 45% of both OHT and HF patients tested, were documented to have severe sleep apnea (See table1).DiscussionWatchPat® is the only HST that proports calculations of total sleep time. It appears to be a viable option for advanced HF and OHT patients with limited access to in-lab PSG. However, WPHST was unable to provide conclusive data for LVAD patients, hypothesized due to lack of native pulsatility. Strikingly, severe sleep apnea was documented in >45% of all patients, and no significant differences when comparing OHT patients to the advanced heart failure population. Continued research and emphasis on testing and treatment of HF patients being considered for advanced therapies is warranted, especially with the current proclivity towards minimum contact post Covid19.