Left and right ventricular function alterations in obstructive sleep apnea patients assessed by 2D speckle tracking echocardiography

Obstructive sleep apnea (OSA) is related to increased left ventricular (LV) transmural pressure, blood pressure instability and increased pulmonary artery pressure (PAP) leading to left and right ventricular (RV) dysfunction and heart failure. 2D speckle tracking echocardiography (STE) is useful method for subclinical biventricular dysfunction diagnosis, thus might help to earlier treatment for OSA patients.

The aim of the study was to evaluate changes of biventricular function and mechanics in patients with OSA.

We obtained 2D STE from 47 obese patients. 13 patients either did not have OSA, or it was mild (apnea/hypopnea index (AHI) 5–14/hour). OSA group (N=34) consisted of subjects with moderate or severe OSA (AHI ≥15/hour). New indexing for LV myocardial mass and LA volume by height was applied according new guidelines for obese patients. Statistical analyses were performed using the SPSS 27.0 software. The value of p<0.05 was considered as statistically significant.

BMI did not differ between groups (p=0.108). Control group patients were younger, had higher female ratio, meanwhile arterial hypertension was more prevalent in OSA group (26 (76.5%) vs. 5 (38.5%), p=0.014). New indexing by height for left ventricular myocardial mass revealed higher LV MMi in OSA patients (p=0.007), and higher prevalence of LV diastolic dysfunction (p=0.023) was found in this group of patients. Moreover, LA reservoir function was significantly lower in OSA group compared to controls p<0.001. LV ejection fraction and conventional RV function parameters (s', fractional area change (FAC)) did not differ between groups, however LV and RV global longitudinal strain was reduced in OSA patients (p=0.035 and p=0.026, respectively). OSA patients had significantly higher RA diameter, and mean PAP (p=0.043 and p=0.037, respectively) (Table 1).

Moderate or severe obstructive sleep apnea is related to reduced biventricular longitudinal strain, more prevalent LV diastolic dysfunction and lower LA reservoir function. New indexing for LV myocardial mass by height helps to identify myocardial structural changes in obese patients with OSA.

Type of funding sources: None.