Sleep Apnea as a Risk Factor for Diastolic Dysfunction: A Systematic Review and Meta-Analysis.

BACKGROUND: This meta-analysis assessed the relationship between obstructive sleep apnea (OSA) and echocardiographic parameters of diastolic dysfunction (DD), which are used in the assessment of heart failure with preserved ejection fraction. METHODS: We searched the databases including Ovid MEDLINE, Ovid Embase, Scopus, Web of Science, Google Scholar, and EBSCO CINAHL from inception up to December 26, 2020. The search was not restricted to time, publication status, or language. Two independent investigators screened the identified studies and extracted the data in duplicate. We conducted a meta-analysis using RevMan v.5. The risk of bias was assessed using Cochrane collaboration tools. Comparisons were made between patients with OSA, diagnosed in-laboratory polysomnography or home sleep apnea testing, and patients without OSA in relation to established markers of DD. RESULTS: Primary search identified 2,512 studies. A total of 18 studies including 2,509 participants were included. The two groups were free of conventional cardiovascular risk factors. Significant structural changes were observed between the two groups. Patients with OSA exhibited greater left atrial volume index (LAVI) (3.94 95% CI [0.8, 7.07]; p = 0.000) and left ventricular mass index (11.10 95% CI [2.56, 19.65]; p = 0.000) as compared to control group. The presence of OSA was also associated with more prolonged deceleration time (10.44 ms 95% CI [0.71, 20.16]; p = 0.04), isovolumic relaxation time (IVRT) (7.85 ms 95% CI [4.48, 11.22]; p = 0.000), and a lower ratio of early to late mitral inflow velocities (E/A) ratio (-0.62 95% CI [-1, -0.24]; p = 0.001) suggestive of early DD. The early mitral inflow velocity to mitral annular early diastolic velocity (E/e') ratio (0.94 95% CI [0.44, 1.45]; p = 0.000) was increased. Linear correlation between severity of OSA and LAVI and IVRT parameters was observed but this association did not sustain for the E/A and E/e'. The ejection fraction was not significantly different between patients with OSA and healthy controls (-0.48 95% CI [-1.18, 0.23]; p = 0.18). CONCLUSION: An association between OSA and echocardiographic parameters of DD was detected that was independent of conventional cardiovascular risk factors. OSA may be independently associated with DD perhaps due to higher LV mass. Investigating the role of continuous positive airway pressure therapy in reversing or ameliorating DD is recommended.

Disparities in Revascularization After ST Elevation Myocardial Infarction (STEMI) Before and After the 2002 IOM Report.

OBJECTIVES: To examine nationwide trends for racial disparities in Percutaneous Coronary Intervention after ST elevated Myocardial Infarction (STEMI). BACKGROUND: The Institute of Medicine (IOM) report published in 2002 showed that African Americans were less likely to receive coronary revascularization such as CABG and stents even after controlling for socioeconomics. It recommended increased awareness of these disparities among health professionals to reduce this. We hypothesized that increased awareness of disparities since this report would have translated to reduction in racial disparities in percutaneous coronary intervention. METHODS: A retrospective analysis was conducted using data from the Agency of Healthcare Research and Quality's (AHRQ) National Inpatient Sample (NIS) 1998-2007. All patients with STEMI during this period were identified. The proportion that received Percutaneous Coronary Intervention (PCI) during the incident admission was compared by different ethnicities over the time period. Multivariable regression for each year was conducted using Poisson regression with robust variances. The analysis controlled for gender, insurance status, co-morbidities, hospital bed size, location and teaching status. RESULTS: Based on the database, about 2.04 million patients were managed for acute Myocardial Infarction from 1998 to 2007, of these 938,176 had STEMI. The primary PCI rate after STEMI among Caucasians was 29.1%, African Americans-23.3% and Hispanics-28.3% [P < 0.001] On multivariate regression, compared to Caucasians, African Americans and Hispanics respectively were 26% (IRR = 0.74) and 16% (IRR = 0.84) less likely to receive PCI (both with P < 0.001) during the entire study period. CONCLUSION: Ethnic disparities in primary PCI after STEMI persist despite the 2002 IOM report.