The effect of long term continuous positive airway pressure treatment on systolic and diastolic function in patients with obstructive sleep apnoea syndrome: A five year observational study

Abstract

Objective: Evaluation of the long-term effects of continuous positive airway presure (CPAP) on mean heart rate and left ventricular systolic and diastolic parameters in obstructive sleep apnea syndrome (OSAS) using conventional and tissue Doppler techniques. Methods: This prospective cohort study is designed to evaluate the long-term effects of CPAP treatments in normotensive OSAS patients. Initially 40 patients aged from eighteen to fifty five with documented OSAS syndrome were evaluated within one month of CPAP treatment. All had high self-reported compliance with treatment. From the latter, 21 patients with uninterrupted CPAP therapy (for at least 5 years, 5 hours per day) were included in the study and further evaluated with treatment. The left ventricular systolic function was assessed on apical four-chamber view using modified Simpson method and diastolic function was evaluated with classic transmitral pulsed and tissue Doppler techniques. Paired t test and Wilcoxon signed rank test had been used to compare the clinical and echocardiography data before and after treatment period. Results: A comparison of values assessed after one month and after 5 years of CPAP therapy, revealed a significant increase in the acceleration time(AT) Em/Am ratio and ejection time (ET) (AT: p=0.04; Em/Am ratio p=0.03 ET: p=0.04) while a significant decrease was observed on deceleration time (DT), isovolumetric relaxation time (IRT), myocardial performance index (MPI), mitral regurgitation (MR) and 24 hour mean heart rate (HR) in all subjects (DT: p=0.02; IVRT: p=0,04; MPI: p=0,01; MR: p≤0.001; HR: p=0.004). Conclusion: We observed a significant improvement in the left ventricular systolic and diastolic function and a significant decrease of 24-hour heart rate and mitral regurgitation with unchanged ejection fraction of the left ventricle with long-term CPAP treatment similar to short-term treatment studies. The long-term maintenance of the beneficial effect of CPAP throughout the 5 year long-term treatment can be one of the pathophysiologic mechanisms that may explain the decrease of cardiovascular mortality observed with long-term CPAP therapy in OSAS patients. (Anadolu Kardiyol Derg 2014; 14: 265-71)

Circadian rhythms in blood pressure, heart rate, hormones, and on polysomnographic parameters in severe obstructive sleep apnea syndrome patients

“…Several studies have shown that the treatment of OSAS with continuous positive airway pressure (CPAP) can reduce pulmonary and/ or hypertensive symptoms [9][10][11][12][13][14][15][16]. In contrast, a significant effect on blood pressure (BP) in treated hypertensive OSAS patients with an apnea-hypopnea index (AHI) of 10 or more events per hour was not described; however, CPAP treatment was used only for 4 weeks [17].…”

An update on cardiovascular effects of obstructive sleep apnoea syndrome

“…CPAP usage was also associated with reduction in blood pressure 69. CPAP treatment was able to improve left ventricular systolic and diastolic functions as well as reduce mitral regurgitation severity and 24 h mean heart rate after 1 month and 5 years in patients with OSA 70. CPAP treatment in patients with OSA without cardiovascular disease reduced systolic blood pressure, however endothelial functions were not affected 71.…”

Can CPAP prevent myocardial damage?

“…However, the long-term effect of CPAP treatment on cardiac function and structure may be beneficial, but clinical trials, randomized studies including significant number of patients and significant follow up period are scant. In this context, the study of Bilge et al (5) in this issue published in the Anatolian Journal of Cardiology adds to the literature because the authors evaluated the cardiac function of OSA patients after 5-year of CPAP effective treatment. Butt et al (6) found a reduction of the posterior wall thickness, improvement in LV ejection fraction (EF), systolic S velocity, and diastolic LV parameters after a mean of 26 weeks of CPAP treatment.…”

“…The studies of our group reinforced the improvement in LV and RV function after 6 months of CPAP, especially in those patients with severe OSA who showed higher frequency of LV and RV impairment (3,11). Strengths of Bilge et al (5) study are related to the design: a) prospective cohort study; b) compliance to treatment of at least 5 hours daily; c) long term follow up of 5 years; d) exclusion of uncontrolled high blood pressure. The authors were also careful when reporting LV and RV variables using echocardiography and Doppler techniques.…”