Diastolic function and functional capacity after a single session of continuous positive airway pressure in patients with compensated heart failure

Abstract

OBJECTIVE:The effects of acute continuous positive airway pressure therapy on left ventricular diastolic function and functional capacity in patients with compensated systolic heart failure remain unclear.METHODS:This randomized, double-blind, placebo-controlled clinical trial included 43 patients with heart failure and a left ventricular ejection fraction <0.50 who were in functional classes I-III according to the New York Heart Association criteria. Twenty-three patients were assigned to continuous positive airway pressure therapy (10 cmH2O), while 20 patients received placebo with null pressure for 30 minutes. All patients underwent a 6-minute walk test (6MWT) and Doppler echocardiography before and immediately after intervention. Clinicaltrials.gov: NCT01088854.RESULTS:The groups had similar clinical and echocardiographic baseline variables. Variation in the diastolic function index (e′) after intervention was associated with differences in the distance walked in both groups. However, in the continuous positive airway pressure group, this difference was greater (continuous positive airway pressure group: Δ6MWT = 9.44+16.05×Δe′, p = 0.002; sham group: Δ6MWT = 7.49+5.38×Δe′; p = 0.015). There was a statistically significant interaction between e′ index variation and continuous positive airway pressure for the improvement of functional capacity (p = 0.020).CONCLUSIONS:Continuous positive airway pressure does not acurately change the echocardiographic indexes of left ventricle systolic or diastolic function in patients with compensated systolic heart failure. However, 30-minute continuous positive airway pressure therapy appears to have an effect on left ventricular diastolic function by increasing functional capacity.

Defining the impact of continuous positive airway pressure therapy on diastolic function in adults with moderate‐to‐severe obstructive sleep apnea

“…Greater severity of OSA and lower mean nocturnal oxygen saturation are associated with worse diastolic dysfunction in observational studies (Baguet et al, 2010; Wachter et al, 2013). Several intervention studies examining the impact of continuous positive airway pressure (CPAP) therapy up to 12 months have shown inconsistent effects on diastolic function (Akar Bayram et al, 2009; Bakker et al, 2020; Bussoni et al, 2014; Butt et al, 2012; Glantz et al, 2017; Shim et al, 2018). Limited information is available on characteristics of subgroups who improve diastolic function with CPAP therapy.…”

Efeitos hemodinâmicos da pressão positiva contínua nas vias aéreas avaliados pelo ecodopplercardiograma

“…Através do CPAP, aplica-se uma pressão maior que a atmosférica ao trato respiratório, resultando em abertura das vias aéreas superiores, aumento do volume pulmonar e da pressão intratorácica (HESS, 2013). Estudos prévios sugerem que o uso de CPAP também está associado a efeitos hemodinâmicos benéficos, tais como melhora da oxigenação, redução da demanda de oxigênio pelo miocárdio e redução da pré e pós-carga do ventrículo esquerdo (BUSSONI et al, 2014).…”