OSAS is associated with early mechanical dyssynchrony and reduced myocardial strain despite preserved global function. A study published in Acta Cardiologica used advanced echocardiographic techniques to assess LV function in 32 patients with moderate (n = 14) or severe (n = 18) OSAS compared with 20 healthy controls.

Participants underwent standard echocardiography, myocardial layer-specific strain, and dyssynchrony analysis, along with norepinephrine level testing. Compared with controls, OSAS patients had higher body mass index (p = .002), diastolic blood pressure (p < .001), and norepinephrine levels (p = .028). They also demonstrated increased LV posterior wall thickness (p < .001) and greater LV mass index (p = .04).

Strain values across the endocardial, myocardial, and epicardial layers were significantly reduced in both moderate and severe OSAS. Severe cases showed marked systolic dyssynchrony, reflected by increased phase standard deviation (p = .044) and shortened time-to-peak strain in anterior-septal and inferior walls (p < .05).

These results indicate that subclinical myocardial dysfunction and early dyssynchrony develop before overt LV impairment in OSAS. Incorporating advanced strain analysis in screening may help identify early cardiac involvement and prevent progression to symptomatic heart failure.