Obstructive Sleep Apnea Syndrome Affects Left Ventricular Diastolic Function

Abstract

Background-The purpose of this study was to determine the role of obstructive sleep apnea syndrome (OSAS) as an independent risk factor for the development of left ventricular diastolic abnormalities. Moreover, we tested the hypothesis that nasal continuous positive airway pressure (nCPAP) improves such alterations in OSAS patients by eliminating apneic events. Methods and Results-In this prospective, randomized, placebo-controlled, double-blind crossover study, 27 consecutive newly diagnosed middle-aged OSAS men with neither controllable factors nor conditions affecting left ventricular diastolic function and 15 healthy control subjects were selected. OSAS patients were randomized to 12 weeks on sham nCPAP and 12 weeks on effective nCPAP application. Echocardiographic parameters, blood pressure recordings, and urinary catecholamine levels were obtained at baseline and after both treatment modalities. At baseline, an abnormal left ventricular filling pattern was present in 15 of the 27 OSAS patients and only in 3 of the 15 control subjects (Pϭ0.020). Impaired relaxation was by far the most common abnormal pattern in both groups (11 and 3 patients, respectively). In OSAS patients, 12 weeks on effective nCPAP induced a significant increase in E/A ratio (PϽ0.01), as well as reductions in mitral deceleration (PϽ0.01) and isovolumic relaxation (PϽ0.05) times. Conclusions-OSAS

A Novel Method for Sensitive Determination of Subclinical Left-Ventricular Systolic Dysfunction in Subjects With Obstructive Sleep Apnea

“…However, most of them have normal ejection fraction despite signs of the heart failure. 16,17 Previous echocardiographic studies using tissue Doppler imaging and speckle-tracking imaging have demonstrated that OSA subjects may develop subclinical LV systolic and diastolic dysfunction. 1,18,19 Altekin et al 20 have also shown on a smaller group of subjects with OSA, using speckle-tracking echocardiography, that longitudinal and circumferential systolic LV dysfunction is detectable in addition to the diastolic dysfunction.…”

Clinical Phenotypes in Heart Failure With Preserved Ejection Fraction

“…In addition to increasing arterial stiffness, obesity is associated with 4‐fold greater prevalence of OSA, which contributes to the pathogenesis of HFpEF through multiple mechanisms: Sympathetic activation increases LV afterload, hypoxic pulmonary vasoconstriction reduces LV preload, oxidative stress stimulates inflammation, and hypoxia predisposes to atrial and ventricular arrhythmias 125, 126, 127, 128, 129…”

“…Independently from hypertension and obesity, OSA impairs LV diastolic function, begets LVH, and thus may hasten HFpEF progression 126, 127, 252, 253, 254, 255, 256, 257, 258. Repetitive sleep arousals and hypoxic episodes heighten sympathetic activity and promote endothelial dysfunction, systemic inflammation, and arterial stiffness that may further increase blood pressure and accelerate atherosclerosis progression 128, 259, 260, 261, 262, 263, 264, 265…”

Recurrent acute pulmonary oedema after aortic and mitral valve surgery due to trachea malacia and obstructive sleep apnoea syndrome

“…1 OSAS also creates right ventricle pressure overload by the mechanical effects of pulmonary obstruction and as such can also affect left ventricular diastolic function. 7,8 We also know from two previous case reports that OSAS may present with recurrent pulmonary oedema. 9,10 In our patient, the first mitral valve reoperation was necessary, due to a demonstrable dysfunction of one of the mitral valve leaflets.…”

“…7,13,14 In summary, OSAS should be suspected in patients with (recurrent) respiratory insufficiency due to pulmonary oedema, especially if no other causes are found. ■…”