Subclinical impairment of dynamic left ventricular systolic and diastolic function in patients with obstructive sleep apnea and preserved left ventricular ejection fraction

Abstract

Background: Hypoxia affects myocardial oxygen supply resulting in subclinical cardiac dysfunction in obstructive sleep apnea (OSA) patients, with cardiovascular complications being associated with increased oxidative burst (OB). The aims of our study were to assess left ventricular (LV) dynamic myocardial deformation and diastolic reserve at rest and upon exercise, along with OB determination in this patients subset. Methods: Conventional echocardiography, Doppler myocardial imaging and LV 2D speckle tracking echocardiography were performed in 55 OSA patients with preserved LV ejection fraction (EF) and 35 age and sex-comparable healthy controls. Peripheral OB levels were evaluated by flow cytometry. Results: Despite comparable LVEF, LV global longitudinal strain (GLS) was significantly reduced in OSA at rest (− 13.4 ± 3.8 vs − 18.4 ± 3.3 in controls, P < 0.001) and at peak exercise (− 15.8 ± 2.6 vs − 23.4 ± 4.3, P < 0.001). Systolic pulmonary artery pressure (sPAP) and E/E′ ratios increase during effort were higher in OSA than in controls (ΔsPAP 44.3% ± 6.4 vs 32.3% ± 5.5, P < 0.0001, and ΔE/E' 87.5% ± 3.5 vs 25.4% ± 3.3, P < 0.0001, respectively). The best correlate of E/E′ at peak stress was peak exertion capacity (r = − 0.50, P < 0.001). OB was also increased in OSA patients (P = 0.001) but, unlike OSA severity, was not associated with LV diastolic dysfunction. Conclusions: Evaluation of diastolic function and myocardial deformation during exercise is feasible through stress echocardiography. OSA patients with preserved LVEF show subclinical LV systolic dysfunction, impaired LV systolic and diastolic reserve, reduced exercise tolerance, and increased peripheral levels of OB. Therapy aimed at increasing LV diastolic function reserve might improve the quality of life and exercise tolerability in OSA patients.

Subclinical left ventricular myocardial dysfunction in patients with obstructive sleep apnea syndrome: insights from noninvasive left ventricular myocardial work analysis

“…As a result of inadequate compression and twisting of extracellular matrix during the systole, the loss of LV suction can induce abnormal relaxation and impaired diastolic function [ 39 ]. The value of e’ was independently associated with GWI in our study, which corroborates previous research [ 40 ]. The significant contribution of deformation in the calculation of MW may explain the independent associations between GLS and MW indices in our study [ 41 ].…”

Sleep disorders in patients with acute and exacerbated chronic heart failure

“…Отношението Е/е' също се променя сигнификантно при двете групи пациенти при физическо натоварване, като то се асоциира силно с нарушена диастолна функция, превалираща в групата с ОСА. Изводът от това е, че пациентите с ОСА макар и клинично без симптоматика са със значително по-нарушена диастолна дисфункция в сравнение с пациенти без ОСА [7].…”

“…ОСА се характеризира с повтарящи се и продължаващи повече от 10 секунди прекъсвания (апнеи) или намаляване (хипопнея) на дихателния поток с над 50% за повече от 10 секунди по време на сън и десатурация ≥ 4%, дължащи се на обструкция на горните дихателни пътища [7].…”

Obstructive sleep apnoea and left ventricular diastolic dysfunction among first responders to the 9/11 World Trade Center terrorist attack: a cross-sectional study

“…A limited number of small studies have consistently reported that patients with moderate-to-severe degree of OSA have a higher prevalence of left ventricular diastolic dysfunction (LVDD) 13–21. LVDD is the impairment of the relaxation ability of the myocardium and the impairment of the LV to fill appropriately without increasing filling pressures 22 23.…”