Impact of obstructive sleep apnea in recruitment of coronary collaterality during inaugural acute myocardial infarction

Obstructive sleep apnea modulates clinical outcomes post-acute myocardial infarction: A large longitudinal veterans' dataset report

BACKGROUND

While the longer-term Obstructive Sleep apnea (OSA)-related intermittent hypoxia (IH) leads to various comorbidities, it has become increasingly evident that OSA confers protective advantages during and after acute myocardial infarction (AMI). We hypothesized in patients who were admitted with acute MI, the presence of OSA is associated with lower in-hospital mortality compared to those without a prior diagnosis of OSA.

METHODS

In this nationwide retrospective study utilizing Veterans Health Administration records, we included patients hospitalized for MI with a history of sleep disorders from 1999 to 2020. We divided patients into two cohorts: those with OSA and those without OSA. The primary outcome was in-hospital mortality during AMI hospitalization. We analyzed the data using logistic regression and calculated the odds ratio of in-hospital mortality.

RESULTS

Out of more than four million veterans with any sleep diagnosis, 76,359 patients were hospitalized with a diagnosis of AMI. We observed 30,116 with OSA (age, 64 ± 10 years; BMI, 33 ± 7 kg/m2) and 43,480 without OSA (age, 68 ± 12 years; BMI, 29 ± 6 kg/m2). The aOR of in-patient mortality (n = 333 (1.1%)) was lower in those with OSA (aOR, 0.43; 95% CI, 0.38 to 0.49) compared to without-OSA (n = 1,102, 2.5%). However, the OSA cohort had a higher proportion of the prolonged length of stay (28.1%).

CONCLUSIONS

Presence of OSA is associated with lower in-hospital mortality among patients admitted for AMI, after adjusting for various demographic and co-morbidity factors. This study highlights the complex relationship between OSA and cardiovascular health and highlights the need for further research in this area.

Effect of obstructive sleep apnoea on coronary collateral vessel development in patients with ST-segment elevation myocardial infarction

BACKGROUND AND OBJECTIVE

The impact of obstructive sleep apnoea (OSA) in the setting of acute ST-segment elevation myocardial infarction (STEMI) is complex and divergent. This study aimed to investigate the association between OSA and coronary collateral vessel (CCV) development in patients with STEMI.

METHODS

The present study prospectively screened 282 STEMI patients with an overnight sleep study. OSA was defined as apnoea-hypopnoea index (AHI) ≥15 events/h. The coronary angiograms were used for the assessment of Rentrop grades representing CCVs.

RESULTS

Among 119 patients enrolled, 60 patients had OSA (50.4%). The prevalence of CCV development (Rentrop grade ≥ 2) was significantly higher in OSA group than in the non-OSA group (43.3% vs. 5.1%, p < 0.001). There was a parallel increase in the Rentrop grades associated with OSA severity and worsening of hypoxaemia indicators (minimum arterial oxygen saturation [SaO₂ ], mean SaO₂ and time with SaO₂ below 90%). After adjustment for clinical and angiographic characteristics, and pre-procedure medications that might interact with OSA, AHI as a continuous variable (OR 1.11, 95% CI 1.08-1.21, p < 0.001) and the presence of OSA (OR 11.41, 95% CI 2.70-48.15, p = 0.001) were both associated with dramatically higher incidence of CCV development.

CONCLUSION

Our study demonstrated that the presence of OSA might augment CCV development in STEMI patients. The potential protective effects and mechanisms of OSA in the acute setting of STEMI should be further investigated in larger studies.

Obstructive sleep apnea confers lower mortality risk in acute ischemic stroke patients treated with endovascular thrombectomy: National Inpatient Sample analysis 2010-2018

BackgroundObstructive sleep apnea (OSA) portends increased morbidity and mortality following acute ischemic stroke (AIS). Evaluation of OSA in the setting of AIS treated with endovascular mechanical thrombectomy (MT) has not yet been evaluated in the literature.

METHODS

The National Inpatient Sample from 2010 to 2018 was utilized to identify adult AIS patients treated with MT. Those with and without OSA were compared for clinical characteristics, complications, and discharge disposition. Multivariable logistic regression analysis and propensity score adjustment (PA) were employed to evaluate independent associations between OSA and clinical outcome.

RESULTS

Among 101 093 AIS patients treated with MT, 6412 (6%) had OSA. Those without OSA were older (68.5 vs 65.6 years old, p<0.001), female (50.5% vs 33.5%, p<0.001), and non-caucasian (29.7% vs 23.7%, p<0.001). The OSA group had significantly higher rates of obesity (41.4% vs 10.5%, p<0.001), atrial fibrillation (47.1% vs 42.2%, p=0.001), hypertension (87.4% vs 78.5%, p<0.001), and diabetes mellitus (41.2% vs 26.9%, p<0.001). OSA patients treated with MT demonstrated lower rates of intracranial hemorrhage (19.1% vs 21.8%, p=0.017), treatment of hydrocephalus (0.3% vs 1.1%, p=0.009), and in-hospital mortality (9.7% vs 13.5%, p<0.001). OSA was independently associated with lower rate of in-hospital mortality (aOR 0.76, 95% CI 0.69 to 0.83; p<0.001), intracranial hemorrhage (aOR 0.88, 95% CI 0.83 to 0.95; p<0.001), and hydrocephalus (aOR 0.51, 95% CI 0.37 to 0.71; p<0.001). Results were confirmed by PA.

CONCLUSIONS

Our findings suggest that MT is a viable and safe treatment option for AIS patients with OSA.

Influence of Obstructive Sleep Apnoea Severity on Coronary Collateral Recruitment During Coronary Occlusion

PURPOSE

Obstructive sleep apnoea (OSA) which results in hypoxia may affect the ability to recruit coronary collaterals. The aim of this study was to determine whether the severity of OSA affects collateral recruitment in patients with total coronary occlusions.

METHODS

Patients with total coronary artery occlusion were reviewed. Records from the sleep investigation laboratory were reviewed to identify those patients who had undergone diagnostic polysomnography. Robust coronary collaterals were those with Rentrop grade 2 or 3 collaterals.

RESULTS

Sixty-four patients with a total coronary occlusion had polysomnography performed, of whom 60 patients had OSA. Thirty-two patients (53.3%) had poor collaterals, whilst 28 (46.7%) had robust collaterals. Twenty-four (40%) patients had mild OSA, 10 (16.7%) had moderate OSA and 26 (43.3%) had severe OSA. Patients with robust collaterals were more likely to be males (96.4% vs 74.3%, p < 0.05) and have a history of hypercholesterolaemia (88.9% vs 51.6%, p < 0.01). Patients with robust collaterals had a lower apnoea-hypopnoea index (13.6 vs 45.5, p < 0.05), a higher MinS_aO₂ (85.4% vs 79.8%, p < 0.05), less time S_aO₂ < 90% (0 min vs 30.4 min, p < 0.05) and lower oxygen desaturation index (6.9 vs 26.8, p < 0.05). Those with moderate OSA had a higher mean Rentrop grade (1.6 ± 0.3) than those with mild OSA (1.5 ± 1.1) and severe OSA (0.6 ± 0.2).

CONCLUSION

The presence of more severe OSA is associated with poorer coronary collateral recruitment in patients with total coronary artery occlusion. The effect of treatment of OSA on subsequent ability to recruit collaterals and other cardioprotective mechanisms requires further research.

Influence of Obstructive Sleep Apnoea on Outcomes in Patients With ST Elevation Myocardial Infarction (STEMI): the Role of the Coronary Collateral Circulation

BACKGROUND

Obstructive sleep apnoea (OSA) occurs frequently in patients with coronary artery disease, with associated intermittent hypoxia a possible stimulus for coronary collateral recruitment through ischaemic preconditioning. We sought to determine whether OSA affects recruitment of coronary collaterals and prognosis of patients presenting with ST elevation myocardial infarction (STEMI).

METHODS

Patients with a STEMI undergoing percutaneous coronary intervention (PCI) from July 2010 to December 2019 were reviewed. Electronic medical records were accessed to determine documented patient history of OSA. Patients with robust collaterals were defined as Rentrop grade 2 or 3.

RESULTS

1,863 patients were included, of which 143 (7.7%) patients had documented evidence of OSA in their health record. Patients with OSA had a higher body mass index (BMI) (30.2 kg/m² vs 27 kg/m², p<0.0001), greater rate of hypertension (61.1% vs 45.1%, p<0.0001), hypercholesterolaemia (47.4% vs 38.4%, p<0.05) and diabetes mellitus (22.6% vs 15.9%, p<0.05). Patients with OSA were more likely to have robust coronary collaterals (OR: 2.2 [95% CI: 1.5-3.2]) and a lower rate of left ventricular (LV) impairment (50.7% vs 63.1%, p<0.01), a higher LV ejection fraction (50.3% vs 46.7%, p<0.0001) and a lower peak troponin-I level (26,452 ng/L vs 39,469 ng/L, p<0.01). There were no differences in rates of in-hospital or longer term mortality, in patients with OSA compared to those without.

CONCLUSIONS

Patients with documented OSA presenting with STEMI appear to have more robust coronary collaterals observed on angiography which likely mediates lower myocardial necrosis. Broader implications of this finding on treatment require further investigation.

Occurrence of Coronary Collaterals in Acute Myocardial Infarction and Sleep Apnea

Background In patients with acute myocardial infarction (MI), cardioprotective effects of obstructive sleep apnea are postulated on account of hypoxemic preconditioning. The aim of this single-center substudy was to investigate a potential association between obstructive sleep apnea and the presence of coronary collaterals in patients with first-time acute MI who have been enrolled in an ongoing, multicenter clinical trial. Methods and Results In TEAM-ASV I (Treatment of Sleep Apnea Early After Myocardial Infarction With Adaptive Servo-Ventilation Trial; NCT02093377) patients with first acute MI who received a coronary angiogram within 24 hours after onset of symptoms underwent polygraphy within the first 3 days. Coronary collaterals were classified visually by assigning a Cohen-Rentrop Score (CRS) ranging between 0 (no collaterals) and 3. Of 94 analyzed patients, 14% had significant coronary collaterals with a CRS ≥2. Apnea-Hypopnea Index (AHI) score was significantly higher in patients with CRS ≥2 compared with those with CRS <2 (31/hour [11-54] versus 13/hour [4-27]; P=0.032). A multivariable regression model revealed a significant association between obstructive AHI and CRS ≥2 that was independent of age, sex, body mass index, and culprit lesion left anterior descending artery (odds ratio [OR], 1.06; 95% CI, 1.01-1.12; P=0.023), but no significant association between coronary collaterals and central AHI (OR, 1.02; 95% CI, 0.97-1.08; P=0.443). Conclusions Patients with first-time acute MI had more extensive coronary collateralization with an increased AHI or rather an increased obstructive AHI. This finding supports the hypothesis that obstructive sleep apnea exerts potential cardioprotective effects, in addition to its known deleterious effects, in patients with acute MI. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT02093377.

A comprehensive review of respiratory, autonomic and cardiovascular responses to intermittent hypoxia in humans

This review explores forms of respiratory and autonomic plasticity, and associated outcome measures, that are initiated by exposure to intermittent hypoxia. The review focuses primarily on studies that have been completed in humans and primarily explores the impact of mild intermittent hypoxia on outcome measures. Studies that have explored two forms of respiratory plasticity, progressive augmentation of the hypoxic ventilatory response and long-term facilitation of ventilation and upper airway muscle activity, are initially reviewed. The role these forms of plasticity might have in sleep disordered breathing are also explored. Thereafter, the role of intermittent hypoxia in the initiation of autonomic plasticity is reviewed and the role this form of plasticity has in cardiovascular and hemodynamic responses during and following intermittent hypoxia is addressed. The role of these responses in individuals with sleep disordered breathing and spinal cord injury are subsequently addressed. Ultimately an integrated picture of the respiratory, autonomic and cardiovascular responses to intermittent hypoxia is presented. The goal of the integrated picture is to address the types of responses that one might expect in humans exposed to one-time and repeated daily exposure to mild intermittent hypoxia. This form of intermittent hypoxia is highlighted because of its potential therapeutic impact in promoting functional improvement and recovery in several physiological systems.

Effects of sleep apnea hypopnea syndromes on cardiovascular events: a systematic review and meta-analysis

PURPOSE

Previous studies suggest that sleep apnea hypopnea syndrome (SAHS) is an independent risk factor that contributes to certain cardiovascular events. However, there are studies arguing that patients with SAHS had lower peak troponin levels when suffering cardiovascular events compared to patients without SAHS, which indicates that there may potentially be a protective effect of SAHS. This meta-analysis aimed to assess the impact of SAHS on cardiovascular events.

METHODS

Databases were searched for studies that examined cardiac biomarkers or reported angiographic data when patients with SAHS experienced cardiovascular events. The data about peak cardiac biomarkers and angiographic coronary lesion were extracted and then used to compute the pooled standardized mean difference (SMD) and 95% confidence interval (95% CI).

RESULTS

Among 26 studies included in the meta-analysis, there was not a definite difference between the SAHS group and the control group for troponins (SMD, 0.05; 95% CI, [- 0.16, 0.26]), creatine kinase (SMD, - 0.08; 95% CI, [- 0.38, 0.22]), and CK-MB (SMD, - 0.11; 95% CI, [- 0.51, 0.29]). However, patients with SAHS revealed worse coronary lesion condition grading via both Gensini score (SMD, 0.63; 95% CI, [0.31, 0.95]) and SYNTAX score (SMD, 0.99; 95% CI, [0.31-1.67]).

CONCLUSIONS

Ischemic preconditioning induced by the intermittent hypoxia at the early stage could generate a cardiac protection effect, which would then benefit SAHS patients encountering a major adverse cardiovascular event.

Acute pulmonary embolism in patients with obstructive sleep apnea: frequency, hospital outcomes, and recurrence

STUDY OBJECTIVES

The objectives of this study were to assess the effect of obstructive sleep apnea (OSA) on the risk of acute pulmonary embolism (PE), hospital outcomes including mortality, and PE recurrence.

METHODS

We retrospectively enrolled adult patients, admitted to Mayo Clinic Hospital in Rochester, Minnesota, within a 5-year period (2009-2013). We compared frequency of PE, hospital mortality, and secondary outcomes in patients with OSA versus patients without OSA. We assessed risk of PE recurrence in relation to compliance with OSA therapy.

RESULTS

Of 25,038 patients, 3,184 (13%) had OSA and 283 (1.1%) experienced PE. Frequency of PE in patients with and without OSA was 2.4% versus 0.9% (odds ratio [OR], 2.51; 95% confidence interval [CI], 1.9-3.3; P < .001). OSA was independently associated with increased risk of PE after adjusting for demographics and comorbidities (OR, 1.44; 95% CI, 1.07-1.9; P = .017). Adjusted hospital mortality was increased in patients with PE (OR, 2.88; 95% CI, 1.7-4.9; P < .001) but not in patients with OSA (OR, 0.98; 95% CI, 0.7-1.4, P = .92). OSA was not a significant determining factor for mortality in patients who experienced a PE (OR, 0.56; 95% CI, 0.1.1-2.78; P = .47), adjusting for demographics, PE severity, and Charlson comorbidity index. Adjusted risk of PE recurrence was greater in patients with OSA compared with patients without OSA (OR, 2.21; 95% CI, 1.05-4.68; P < .04). The patients compliant with OSA therapy had a lower rate of PE recurrence (16% vs 32%; P = not significant).

CONCLUSIONS

Although OSA significantly increases risk of acute PE occurrence and recurrences, related hospital mortality was not greater in patients with OSA compared with those without OSA. OSA therapy might have a modifying effect on PE recurrence.

Sleep Apnea and Cardiovascular Disease: An Enigmatic Risk Factor

Synchronization of molecular, metabolic, and cardiovascular circadian oscillations is fundamental to human health. Sleep-disordered breathing, which disrupts such temporal congruence, elicits hemodynamic, autonomic, chemical, and inflammatory disturbances with acute and long-term consequences for heart, brain, and circulatory and metabolic function. Sleep apnea afflicts a substantial proportion of adult men and women but is more prevalent in those with established cardiovascular diseases and especially fluid-retaining states. Despite the experimental, epidemiological, observational, and interventional evidence assembled in support of these concepts, this substantial body of work has had relatively modest pragmatic impact, thus far, on the discipline of cardiology. Contemporary estimates of cardiovascular risk still are derived typically from data acquired during wakefulness. The impact of sleep-related breathing disorders rarely is entered into such calculations or integrated into diagnostic disease-specific algorithms or therapeutic recommendations. Reasons for this include absence of apnea-related symptoms in most with cardiovascular disease, impediments to efficient diagnosis at the population level, debate as to target, suboptimal therapies, difficulties mounting large randomized trials of sleep-specific interventions, and the challenging results of those few prospective cardiovascular outcome trials that have been completed and reported. The objectives of this review are to delineate the bidirectional interrelationship between sleep-disordered breathing and cardiovascular disease, consider the findings and implications of observational and randomized trials of treatment, frame the current state of clinical equipoise, identify principal current controversies and potential paths to their resolution, and anticipate future directions.

Obstructive sleep apnoea in acute coronary syndrome

Obstructive sleep apnoea (OSA) syndrome affects about 13% of the male and 7–9% of the female population. Hypoxia, oxidative stress and systemic inflammation link OSA and cardiovascular and metabolic consequences, including coronary artery disease. Current research has identified several clinical phenotypes, and the combination of breathing disturbances during sleep, systemic effects and end-organ damage might help to develop personalised therapeutic approaches. It is unclear whether OSA is a risk factor for acute coronary syndrome (ACS) and might affect its outcome. On the one hand, OSA in patients with ACS may worsen prognosis; on the other hand, OSA-related hypoxaemia could favour the development of coronary collaterals, thereby exerting a protective effect. It is unknown whether positive airway pressure treatment may influence adverse events and consequences of ACS. In non-sleepy patients with OSA and stable coronary artery disease, randomised controlled trials failed to show that continuous positive airway pressure (CPAP) treatment protected against cardiovascular events. Conversely, uncontrolled studies suggested positive effects of CPAP treatment in such patients. Fewer data are available in subjects with ACS and OSA, and results of randomised controlled studies on the effects of CPAP are expected shortly. Meanwhile, the search for reliable markers of risk continues. Recent studies suggest that daytime sleepiness may indicate a more severe OSA phenotype with regard to cardiovascular risk. Finally, some studies suggest sex-related differences. The picture is still incomplete, and the potential role of OSA in patients with ACS awaits confirmation, as well as clear definition of subgroups with different degrees of risk.

Evidence suggests a high prevalence of OSA in ACS. While some studies suggest hypoxia may have a protective effect, the majority show increased adverse cardiac outcomes. Treatment effectiveness on ACS outcome crucially depends on patients' adherence.http://bit.ly/2Id97ec

Obstructive sleep apnoea and coronary artery disease

Obstructive sleep apnoea (OSA) is a highly prevalent disorder, which causes significant nocturnal and daytime symptoms, reduced quality of life, and impaired functional capacity. Importantly, however, OSA also appears to predispose to the development of a number of cardiovascular and metabolic diseases, including diabetes, hypertension, and stroke. In this review we explore its relationship with coronary artery disease (CAD), discussing mechanisms whereby it may promote the development of atherosclerosis, evidence of its effect on CAD incidence and outcomes, and coronary imaging studies in subjects with OSA. Finally, we shall evaluate the current evidence regarding the impact of continuous positive airway pressure therapy on CAD outcomes in OSA patients.

Timely diagnosis and treatment of sleep apnea reduce cardiovascular sequelae in patients with myocardial infarction

Background

The present study aimed to test if the temporal sequence between sleep apnea (SA) diagnosis and incident myocardial infarction (MI) was associated with the long-term mortality and cardiovascular event in a community-based cohort.

Methods

We retrieved data from 9,453 incident MI patients between Jan. 1^st 2000 and Dec. 31^st 2012 from the Taiwan National Health Insurance Research Database. The study subjects included 207 MI patients with SA (SA-MI), further stratified into 110 with pre-existing SA before MI (SA-bMI) and 96 diagnosed with SA after MI (SA-pMI). The median follow-up period was 4.2 years. Propensity-score-matched controls were selected from 9,246 non-SA MI patients (non-SA-MI). The association of SA and outcomes including all-cause mortality and major adverse cardiac and cerebrovascular events (MACCEs) were analyzed by a Cox proportional hazards model.

Results

The result showed that SA was not associated with mortality regardless of the timing of SA diagnosis. SA-pMI was associated with increased risk of MACCEs (Hazard ratio [HR]: 1.412, 95% confidence interval [CI]: 1.037~1.923, p = 0.029) including re-MI or revascularization and ischemic heart disease hospitalization. Such an association was most significant for SA diagnosed within one year after MI (HR: 2.029, 95% CI: 1.265~3.254, p = 0.003), which was not seen in patients treated with continuous positive airway pressure (CPAP).

Conclusion

The temporal sequence and the time interval between SA diagnosis and incident MI was associated with the cardiovascular events after MI, especially within one year after MI. Early assessment for the presence of SA after incident MI and early CPAP intervention may reduce the risk of further adverse cardiovascular events.

Intermittent Hypoxia Induced Formation of "Endothelial Cell-Colony Forming Units (EC-CFUs)" Is Affected by ROS and Oxidative Stress

Intermittent hypoxia (IH)—the hallmark of obstructive sleep apnea (OSA)—increases leukocyte activation, production of NADPH-oxidase dependent reactive oxygen species (ROS) and oxidative stress, affecting endothelial function. However, IH and oxidative stress can also stimulate adaptive-protective mechanisms by inducing the development of Endothelial Cell-Colony Forming Units (EC-CFUs), which are considered as a good surrogate marker for endothelial progenitor cells (EPCs), and likely reflect a reparatory response to vascular damage or tissue ischemia by leukocytes. Blood samples were obtained from 15 healthy consenting volunteers to evaluate the effects of IH and sustained hypoxia (SH) in vitro on EC-CFUs development and functions. The variables measured included: their numbers, the area, the proliferative capacity and ROS production. Additionally, NADPH-oxidase, VEGF and nuclear factor-erythroid 2 related factor 2 (Nrf2) expression, as well as their paracrine effects on endothelial tube formation were determined. The involvement of ROS was probed using the anti-oxidant N-acetylcysteine (NAC) and NADPH-oxidase inhibitors apocynin and diphenyl-iodide. Compared to normoxia, IH-dependent increases in EC-CFUs numbers were observed, showing an individual donor-dependent trait. Also, the expression of VEGF and gp91phox, a subunit of NADPH-oxidase, were significantly increased. ROS production and oxidative stress markers were also significantly increased, but Nrf2 expression and colony size were unaffected by IH. Additionally, conditioned media harvested from IH- and SH-treated mature EC-CFUs, significantly increased endothelial tube formation. These effects were markedly attenuated or diminished by the ROS and NADPH-oxidase inhibitors employed. In conclusion, we show here for the first time that IH-associated oxidative stress promotes EC-CFUs' vascular and paracrine capacities through ROS. However, the large inter-individual variability expressed in EC-CFUs numbers and functions to a given IH stimulus, may represent an individual trait with a potential clinical significance.

Pulmonary infarction secondary to pulmonary embolism: An evolving paradigm

BACKGROUND AND OBJECTIVE

Pulmonary infarction (PI) from pulmonary embolism (PE) remains an entity of unclear aetiology. PI has been thought to occur in elderly patients with cardiopulmonary disease. We hypothesize younger patients without cardiopulmonary comorbidities are at highest risk. Our study aims to characterize PI clinically and radiographically, determine associated risk factors and determine their clinical significance.

METHODS

We conducted a single-centre retrospective review of 367 consecutive patients with PE. Clinical and radiographic data were compared between patients with and without PI using chi-square and F-tests. Univariate and multivariate analyses were performed to evaluate risk factors for PI.

RESULTS

PI occurred in 62 of 367 patients with acute PE (16.9%). Patients with PI were significantly younger (48 ± 20.3 vs 59.6 ± 17.2 years, P < 0.01), with lower pulmonary embolism severity index (PESI) scores (73.7 ± 38.1 vs 91.9 ± 37.5 years, P < 0.01) and endorsed chest pain with significantly higher frequency (65% vs 39%, P < 0.01). There was no significant difference in other clinical symptoms, hospital length of stay or mortality between groups. Presence of radiographic cardiopulmonary disease was significantly lower in patients with PI (emphysema: 5% vs 22%, P = <0.01; aortic atherosclerosis: 23% vs 43%, P = <0.01). In multivariate analysis, age ≤33 (OR 3.5 CI: 1.37-8.95, P < 0.01), chest pain (OR 2.15 CI: 1.15-4.00, P = 0.02) and pleural effusion (OR 2.18 CI: 1.08-4.41, P = 0.03) increased PI risk and presence of emphysema decreased risk (OR 0.21 CI: 0.06-0.70, P = 0.01).

CONCLUSION

Younger patients without cardiopulmonary comorbidities are at highest risk of PI. Chest pain and pleural effusion significantly increased risk of PI while presence of radiographic emphysema reduced risk.

Sleep Apnea in Patients Hospitalized With Acute Ischemic Stroke: Underrecognition and Associated Clinical Outcomes

STUDY OBJECTIVES

To evaluate clinical recognition of sleep apnea and related outcomes in patients hospitalized with acute ischemic stroke.

METHODS

A retrospective study of all patients hospitalized with acute ischemic stroke from April 2008 to December 2014. The primary predictor and outcome variables were sleep apnea and hospital mortality, respectively. Secondary outcomes were mechanical ventilation, hospital length of stay, and the survivor's functional level by the modified Rankin scale. A sensitivity multivariate regression analysis included the propensity score for cardiovascular comorbidities and sleep apnea.

RESULTS

Of 989 patients, 190 (19%) were considered to have sleep apnea. Only 42 patients (22%) received any treatment for sleep apnea during the hospital stay. Despite higher prevalence of cardiovascular comorbidities, the patients with sleep apnea had lower hospital mortality, 1% versus 5.6% in patients without sleep apnea (odds ratio [OR] 0.18; 95% confidence interval [CI], 0.03-0.58, P = .002). Only the National Institutes of Health Stroke Scale (NIHSS) and the Glasgow coma scale (GCS) were significant predictors of adjusted hospital mortality (OR 1.06, 95% CI 1.01-1.11, P = .01 and OR 0.61, 95% CI 0.51-0.69, P ≤ .001, respectively). A composite clinical propensity score for sleep apnea and cardiovascular comorbidities was significantly associated with decreased mortality, independent to either NIHSS (OR 0.11, 95% CI 0.017-0.71; P = .02) or GCS (OR 0.07, 95% CI 0.01-0.52; P = .01).

CONCLUSIONS

Prevalence of sleep apnea in our study was low, likely because of clinical underrecognition. Despite having more cardiovascular disease, the patients with acute stroke and sleep apnea had less severe neurological injury and lower unadjusted mortality than those without a history of sleep apnea.

The relationship between apnoea hypopnoea index and Gensini score in patients with acute myocardial infarction undergoing emergency primary percutaneous coronary intervention

BACKGROUND

Sleep apnoea hypopnoea syndrome (SAHS) is characterised by repetitive nocturnal hypoxemia and has a high prevalence among patients with acute myocardial infarction (AMI). But there are few studies on patients with AMI undergoing emergency primary percutaneous coronary intervention (pPCI). In this study, we want to find the prevalence of SAHS among patients with AMI undergoing emergency pPCI and determine whether SAHS would worsen the condition among these people, and especially affect the damage degree of the coronary artery.

METHODS

Over four months, 95 patients admitted for the first time for AMI were observed. All of them had emergency primary PCIs. A total of 86 patients accepted the sleep study and were divided into four groups according to the apnoea hypopnoea index (AHI): SAHS was diagnosed when AHI ≥5/h and was defined as mild for AHI ≥5/h and <15/h, moderate for AHI ≥15/h and <30/h, and severe for AHI ≥30/h. On the contrary, the patients whose AHI <5/h were Non-SAHS. And the characteristics of the patients among these four groups were compared. According to the time of chest pain onset, the number of the patients between SAHS and non-SAHS, and patients' AHI during three intervals of one day were measured and compared; Makers including the sensitivity of serum troponin T (hs-TnT), creatine kinase isoenzyme MB (CK-MB), left ventricular ejection fraction (LVEF), pro-brain-type natriuretic peptide (pro-BNP), Gensini score and collateral vessels between the SAHS and non-SAHS were compared. And the relationships between the AHI of these patients and the markers were analysed.

RESULTS

Of the 86 patients studied, 65 had SAHS, representing a SAHS prevalence of 75.58% among patients with AMI undergoing emergency pPCI. There were significant differences in average ages, smoking and arrhythmia (P<0.05) between these four groups. There was no significant difference between AMI patients with or without SAHS regarding the day-night pattern. But there showed significant differences between SAHS and non-SAHS in Gensini score (P<0.05) and pro-BNP (P<0.05). Also, there were positive correlations between AHI and Gensini score (r=0.490, P<0.05) and pro-BNP (r=0.338, P<0.05).

CONCLUSIONS

Among patients with AMI undergoing emergency pPCI, there is a high prevalence of SAHS. There are also positive correlations between AHI and Gensini score, and pro-BNP. Therefore, guided by the results, should we conduct a routine screening to those patients normally and could we relieve the damage to the coronary artery by curing the SAHS?

Neurological outcomes of patients with history of obstructive sleep apnea after a cardiac arrest

BACKGROUND

Cardiac arrest survivors may have disabilities due to hypoxic brain injury. Patients with obstructive sleep apnea are exposed to intermittent hypoxemia that may lead to ischemic preconditioning. We have hypothesized that patients with obstructive sleep apnea have better neurological outcomes following a cardiac arrest due to preconditioning of the brain.

METHODS

We retrospectively analyzed all the survivors of in-hospital cardiac arrest from January 2006 to September 2016. Patients with confirmed or suspected obstructive sleep apnea were selected for further analysis and those without were used as comparison. Primary outcome was neurological functionality on hospital discharge by the Cerebral Performance Category.

RESULTS

A total of 739 patients had cardiac arrest within the study period. The immediate mortality rate was 59% (N=43) in patients with obstructive sleep apnea and 94% (N=623) in those without (p<0.001). Approximately 10% (N=73) were discharged alive and these were selected for further analysis. Patients without obstructive sleep apnea had more frequently "Poor" outcomes compared to those with obstructive sleep apnea (OR 2.91; 95% CI, 1.11-7.66; p=0.03). After adjusting in a multivariate analysis, obstructive sleep apnea was "protective" of "Poor" neurological outcomes: adjusted OR 0.21; 95% CI, 0.06-0.64; p=0.01.

CONCLUSION

Patients with obstructive sleep apnea had better unadjusted survival rates, and favorable adjusted neurological outcomes at discharge compared to those without obstructive sleep apnea. These results suggest that obstructive sleep apnea patients may tolerate better acute brain ischemia due to preconditioning.

Perioperative sleep apnea: a real problem or did we invent a new disease?

Depending on the subpopulation, obstructive sleep apnea (OSA) can affect more than 75% of surgical patients. An increasing body of evidence supports the association between OSA  and perioperative complications, but some data indicate important perioperative outcomes do not differ between patients with and without OSA. In this review we will provide an overview of the pathophysiology of sleep apnea and the risk factors for perioperative complications related to sleep apnea. We also discuss a clinical algorithm for the identification and management of OSA patients facing surgery.