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Background Obstructive sleep apnea (OSA) is a risk factor of several cardiovascular diseases. We investigated the association between aortic root diameter and hypoxia-related parameters in hypertensive patients with OSA. Methods Our study included 242 hypertensive patients with OSA (52 mild, 71 moderate and 119 severe). All the patients underwent echocardiography for measuring aortic root diameter and polysomnography for measuring apnea-hyponea index (AHI), oxygen desaturation index and time spent with oxygen desaturation less than 90%. Results The study patients included 19.8% women and had a mean (±SD) age of 49.9±12.9 years, a mean aortic root diameter of 33.4±2.6 mm and a prevalence of echocardiographic aortic root dilation of 3.7%. Patients with mild, moderate and severe OSA had similar echocardiographic left ventricular structure. However, patients with severe OSA had a significantly (P<0.05) greater aortic root diameter (33.9±2.4 mm vs 32.4±2.2 and 33.4±2.9 mm, respectively) and higher prevalence of aortic root dilatation (5% vs 1% and 3%, respectively) than those with mild and moderate OSA. Aortic root diameter corrected by body height was significantly (P<0.001) associated with AHI, oxygen desaturation index and time spent with oxygen desaturation less than 90% (r=0.23 to 0.33). After adjustment for various confounding factors, the associations between aortic root diameter and polysomnography parameters remained statistically significant (P<0.05). Conclusions The severity of OSA was associated with the aortic root diameter. Patients with severe OSA had a greater aortic root diameter.

Background Screening for atrial fibrillation before onset of symptoms and the subsequent initiation of oral anticoagulants could prevent stroke and death. The most cost-effective strategy to screen for atrial fibrillation in a population at high risk aged 65 years and older is unknown. Therefore, we aimed to investigate whether more frequent electrocardiography (ECG) recordings would significantly improve the detection of atrial fibrillation compared with annual ECG screenings. MethodsWe did a randomised controlled trial that compared different screening frequencies of 30 s single-lead ECG (AliveCor Heart Monitor) in the detection of atrial fibrillation in Chinese residents (≥65 years) in five community health centres in Shanghai, China. Only participants without history of atrial fibrillation and without atrial fibrillation rhythm at baseline were eligible for inclusion in the trial. Random assignment was done with the use of a random number table and stratified for study site. Participants were randomly assigned in a 1:1 ratio to annual or quarterly screening groups. The quarterly screening group was further randomly assigned in a 3:1 ratio to subgroups of quarterly screening and quarterly screening plus (which involved ECG screening once per week for the first month of follow-up, then quarterly for the remainder of follow-up). The primary outcome was the detection rate of atrial fibrillation. The intention-to-treat analysis was done for all randomly assigned patients who had at least one ECG recording during follow-up. This trial was registered at ClinicalTrials.gov, NCT02990741, and terminated on Oct 31, 2020.