Impact of sleep-disordered breathing in patients with acute myocardial infarction: a retrospective analysis

Sleep apnea in patients undergoing coronary artery bypass grafting: Impact on perioperative outcomes

Sleep-disordered breathing is common in patients with coronary artery disease undergoing coronary artery bypass grafting. Sleep-disordered breathing is associated with increased perioperative morbidity, arrhythmias (e.g. atrial fibrillation) and mortality. This study investigated the impact of sleep-disordered breathing on the postoperative course after coronary artery bypass grafting, including development of atrial fibrillation. This prospective single-centre cohort study included adults undergoing coronary artery bypass grafting. All were screened for sleep-disordered breathing (polygraphy) and atrial fibrillation (electrocardiogram) preoperatively; those with known sleep-disordered breathing or atrial fibrillation were excluded. Endpoints included new-onset atrial fibrillation, duration of mechanical ventilation, time in the intensive care unit, and postoperative infection. Regression analysis was performed to identify associations between sleep-disordered breathing and these outcomes. A total of 508 participants were included (80% male, median age 68 years). The prevalence of any (apnea-hypopnea index ≥ 5 per hr), moderate (apnea-hypopnea index = 15-30 per hr) and severe (apnea-hypopnea index > 30 per hr) sleep-disordered breathing was 52.9%, 9.3% and 10.2%, respectively. All-cause 30-day mortality was 0.98%. After adjustment for age and sex, severe sleep-disordered breathing was associated with longer respiratory ventilation support (crude odds ratio [95% confidence interval] 5.28 [2.18-12.77]; p < 0.001) and higher postoperative infection rates (crude odds ratio 3.32 [1.45-7.58]; p < 0.005), but not new-onset atrial fibrillation or mortality. New-onset atrial fibrillation was significantly associated with postoperative infection and prolonged hospital stay. The significant associations between sleep-disordered breathing and several adverse outcomes after coronary artery bypass grafting support the need for preoperative sleep-disordered breathing screening in individuals undergoing cardiac surgery.

A systematic review on the association of sleep-disordered breathing with cardiovascular pathology in adults

Sleep-disordered breathing (SDB) is characterized by repeated breathing pauses during sleep. The prevalence of SDB varies widely between studies. Some longitudinal studies have found an association of SDB with incident or recurrent cardiovascular events. We sought to systematically describe the current data on the correlation between SDB and cardiovascular pathology. Studies were included if they were original observational population-based studies in adults with clearly diagnosed SDB. The primary outcomes include all types of cardiovascular pathology. We carried out pooled analyses using a random effects model. Our systematic review was performed according to the PRISMA and MOOSE guidelines for systematic reviews and was registered with PROSPERO. In total, 2652 articles were detected in the databases, of which 76 articles were chosen for full-text review. Fourteen studies were focused on samples of an unselected population, and 8 studies were focused on a group of persons at risk for SDB. In 5 studies, the incidence of cardiovascular pathology in the population with SDB was examined. In total, 49 studies described SDB in patients with cardiovascular pathology. We found an association between SDB and prevalent /incident cardiovascular disease (pooled OR 1.76; 95% CI 1.38–2.26), and pooled HR (95% CI 1.78; 95% CI 1.34–2.45). Notably, in patients with existing SDB, the risk of new adverse cardiovascular events was high. However, the relationship between cardiovascular disease and SDB is likely to be bidirectional. Thus, more large-scale studies are needed to better understand this association and to decide whether screening for possible SDB in cardiovascular patients is reasonable and clinically significant.

Association of objective and subjective parameters of obstructive sleep apnea with plasma aldosterone concentration in 2,066 hypertensive and 25,368 general population

STUDY OBJECTIVES

Obstructive sleep apnea (OSA) severity has been suggested in aldosterone elevation in resistant hypertension, whereas it is undetermined in the rest population. We explored the association of OSA parameters with plasma aldosterone concentration (PAC) in participants with and without hypertension.

METHODS

We enrolled clinically hypertensive patients with polysomnography and PAC data under no interfering agents, compared (log) PAC, and assessed the linearity of log PAC by tertiles (T1/2/3) of sleep parameters and their association using linear regression by gender and age. We enrolled participants with and without hypertension who had No-SAS scale and PAC data from the community and duplicated the observations from clinical setting considering age, gender, and presence of hypertension.

RESULTS

Of the 2,066 clinical patients with hypertension (1,546 with OSA), men participants (n=1,412), log apnea-hypopnea index (p=0.043), apnea index (AI, p=0.010), and lowest oxygen saturation (LSaO₂, p=0.013) showed significant linearity with log PAC. Log AI (B=0.04, 95%CI: 0.01,0.07, p=0.022) and log LSaO₂ (B=-0.39, 95%CI: -0.78,-0.01, p=0.044) showed significant positive and negative linear associations with log PAC in regression. In community dwellers, 6,417 participants with untreated hypertension (2,642 with OSA) and 18,951 normotensive participants (3,000 with OSA) were included. Of the men participants with and without hypertension, the OSA group showed significantly higher (log) PAC than did their counterparts, and log No-SAS score showed positive association with log PAC (hypertension: B=0.072, 95%CI: 0.002,0.142, p=0.043; normotension: B=0.103, 95%CI: 0.067,0.139, p<0.001) in linear regression analysis, which were consistent in all age groups.

CONCLUSIONS

OSA parameters were positively associated with PAC in normotensive and hypertensive participants, indicating that OSA may increase circulating aldosterone, especially in men.

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.

Female Patients With Sleep-Disordered Breathing Display More Frequently Heart Failure With Preserved Ejection Fraction

Objective: Sleep-disordered breathing (SDB) is a widespread disease that is often associated with heart failure (HF) with preserved ejection fraction (HFpEF). HFpEF is more frequent in women than in men, but detailed pathomechanisms remain unclear. We investigated HFpEF in women and men in a high-risk cohort with SDB monitoring.

Methods and Results: Three hundred twenty-seven patients (84.4% men) undergoing elective coronary artery bypass grafting were prospectively subjected to SDB monitoring, and an apnea–hypopnea index (AHI) ≥15/h defined SDB. HF was classified according to current guidelines. HFpEF was significantly more frequent in SDB patients compared to those without SDB (28 vs. 17%, P = 0.016). This distribution was driven by an increased frequency of HFpEF in female SDB patients (48% vs. only 25% in male, P = 0.022). In accordance, female patients with SDB exhibited significantly more impaired diastolic left ventricular filling compared to men (echocardiographic E/e′). In contrast to men, in women, minimum oxygen saturation (O_2min, measured by polygraphy, R² = 0.470, P < 0.001) and time of oxygen saturation <90% (R² = 0.165, P = 0.044) were significantly correlated with E/e′. Moreover, the correlation between O_2min and E/e′ was significantly different in women compared to men (P < 0.001). Intriguingly, this association remained independent of clinical covariates in women [age, body mass index, systolic contractile dysfunction, diabetes mellitus, and glomerular filtration rate (GFR), R² = 0.534, P = 0.042, multivariate regression analysis]. Since angiotensin II signaling has been mechanistically linked to HF, we measured protein expression of its cleavage enzyme ACE2 in human right atrial appendage biopsies (Western blot). Intriguingly, we found a significantly decreased ACE2 expression preferentially in women with SDB (2.66 ± 0.42 vs. 4.01 ± 2.47 in men with SDB, P = 0.005). In accordance, left ventricular mass index was significantly increased in women with SDB compared to women without SDB.

Conclusion: In patients with SDB, HFpEF and diastolic dysfunction were more frequent in women compared to men. In contrast to men, the severity of SDB was associated with the degree of diastolic dysfunction in women. These insights might help to find sex-specific therapies for patients with sleep-disordered breathing and heart failure.

Clinical Trial Registration: Unique identifier: NCT02877745, URL: http://www.clinicaltrials.gov.

Obstructive sleep apnea and influenza infection: a nationwide population-based cohort study

OBJECTIVES

Influenza infection could trigger acute myocardial infarction. Obstructive sleep apnea (OSA) increases risk for myocardial infarction. Evidence evaluating the risk of influenza in patients with OSA is limited. We aimed to investigate the association between OSA and influenza using a nationwide population-based data set.

METHODS

A total of 5483 individuals with OSA were enrolled from January, 2000, to December, 2012, and compared with a control group of 21,932 individuals who had never been diagnosed with OSA (at a 1:4 ratio propensity score matched by age, sex, index years, and comorbidities) in the context of subsequent influenza infection. Cox proportional hazard regression analysis was conducted to analyze the association between OSA and influenza incidence. We conducted sensitivity analyses to examine our finding.

RESULTS

During the 1.81 (±2.12) years of the follow-up period, the incidence rate of influenza infection was higher in the OSA group compared with the non-OSA group (36.40 and 30.09 per 100 person-years). After adjusting for age, sex, comorbidities, outpatients visits, the risk of influenza infection among patients with OSA was significantly higher (hazard ratio = 1.18; 95% confidence interval = 1.14-1.23; P < 0.001). Sensitivity analyses showed consistent positive association. Males with OSA had increased risk of influenza infection compared with males without OSA (adjusted HR, 1.21; 95% CI, 1.16-1.27; P value for interaction = 0.03).

CONCLUSIONS

This study found a significantly higher risk of influenza infection in patients with OSA, and sex acted as an effect modifier between OSA and risk of influenza infection.

Subjective Poor Sleep Quality is Associated with Higher Blood Pressure and Prevalent Hypertension in General Population Independent of Sleep Disordered Breathing

OBJECTIVE

To explore the relationship of subjective sleep quality with blood pressure (BP) and hypertension by considering the influence of sleep disordered breathing (SDB) and age in the general population.

METHODS

We evaluated sleep quality using the Pittsburgh sleep quality index (PSQI) and SDB using NoSAS score and measured BP in randomly selected adults in China in 2019. Sleep quality is categorized into four groups as very good, fairly good, fairly bad and very bad. SDB is defined as NoSAS score ≥8. Hypertension is defined as systolic BP ≥140 mmHg and/or diastolic BP ≥90 mmHg, and/or use of antihypertensive medicine within previous 2 weeks. Multi-variable linear and logistic regression analyses were used to assess the association of global PSQI score and sleep quality with BP and prevalent hypertension.

RESULTS

In the 33,341 participants (53.4% women, median age: 48 years), prevalence of hypertension significantly increased from very good to very bad sleepers in total (34.3 vs 42.6 vs 50.3 vs 58.5%), SDB (61.2 vs 68.3 vs 73.3 vs 75.5%) and non-SDB participants (26.8 vs 33.1 vs 40.1 vs 50.9%). In multiple linear regression, PSQI global score showed significant positive association with BP levels in total, SDB and non-SDB participants, consistent in sensitivity analysis by excluding participants who were taking antihypertensives, and in participants aged <60 years in age-stratified analysis. In multivariable logistic regression, odds ratio for presence of hypertension significantly increased from very good to very bad sleepers in total (1 vs 1.08 vs 1.22 vs 1.48), SDB (1 vs 1.17 vs 1.35 vs 1.28) and non-SDB participants (1 vs 1.05 vs 1.14 vs 1.53), consistent in participants aged <60 years.

CONCLUSION

Poor subjective sleep quality is significantly associated with higher BP and prevalent hypertension, independent of SDB in the young- and middle-aged general population, indicating potential of improving sleep quality to lower BP and optimize hypertension management at population level.

Obstructive sleep apnoea but not central sleep apnoea is associated with left ventricular remodelling after acute myocardial infarction

Obejctive

Obstructive sleep apnoea (OSA) increases left ventricular transmural pressure more than central sleep apnoea (CSA) owing to negative intrathoracic pressure swings. We tested the hypothesis that the severity of OSA, and not CSA, is therefore associated with spheric cardiac remodelling after acute myocardial infarction.

Methods

This sub-analysis of a prospective observational study included 24 patients with acute myocardial infarction who underwent primary percutaneous coronary intervention. Spheric remodelling, calculated according to the sphericity index, was assessed by cardiac magnetic resonance imaging at baseline and 12 weeks after acute myocardial infarction. OSA and CSA [apnoea-hypopnoea index (AHI) ≥ 5/hour] were diagnosed by polysomnography.

Results

Within 12 weeks after acute myocardial infarction, patients with OSA exhibited a significant increase in systolic sphericity index compared to patients without sleep-disordered breathing (no SDB) and patients with CSA (OSA vs. CSA vs. no SDB: 0.05 ± 0.04 vs. 0.01 ± 0.04 vs. − 0.03 ± 0.03, p = 0.002). In contrast to CSA, the severity of OSA was associated with an increase in systolic sphericity index after accounting for TIMI-flow before percutaneous coronary intervention, infarct size, pain-to-balloon-time and systolic blood pressure [OSA: B (95% CI) 0.443 (0.021; 0.816), p = 0.040; CSA: 0.193 (− 0.134; 0.300), p = 0.385].

Conclusion

In contrast to CSA and no SDB, OSA is associated with spheric cardiac remodelling within the first 12 weeks after acute myocardial infarction. Data suggest that OSA-related negative intrathoracic pressure swings may contribute to this remodelling after acute myocardial infaction.

Graphic abstract

Electronic supplementary material

The online version of this article (10.1007/s00392-020-01684-z) contains supplementary material, which is available to authorized users.

Prevalence of Undiagnosed Obstructive Sleep Apnea Among Patients Hospitalized for Cardiovascular Disease and Associated In-Hospital Outcomes: A Scoping Review

BACKGROUND

Obstructive sleep apnea (OSA) is associated with long-term cardiovascular morbidity and is highly prevalent in patients with cardiovascular disease (CVD). The objectives of this scoping review were to determine the prevalence of OSA inpatients hospitalized for CVD and to map the range of in-hospital outcomes associated with OSA.

METHODS

We searched MEDLINE(R), Embase, and Cochrane Databases for articles published from 1946-2018. We included studies involving non-surgical adults with OSA or at high risk of OSA who were hospitalized for CVD. The outcomes were considered as in-hospital if they were collected from admission up to 30 days post-discharge from hospital.

RESULTS

After the screening of 4642 articles, 26 studies were included for qualitative synthesis. Eligible studies included patients presenting with acute coronary syndromes (n = 19), congestive heart failure (n = 6), or any cardiovascular disease (n = 1). The pooled prevalence of OSA in cardiac inpatients was 48% (95% CI: 42-53). The in-hospital outcomes reported were mortality (n = 4), length of stay (n = 8), left ventricular ejection fraction (n = 8), peak troponin (n = 7), peak B-type natriuretic peptide (n = 4), and composite cardiovascular complications (n = 2).

CONCLUSIONS

OSA is highly prevalent in the cardiac inpatient population. The outcomes reported included mortality, cardiac function, cardiac biomarkers, and resource utilization. There are significant knowledge gaps regarding the effect of treatment and OSA severity on these outcomes. The findings from this review serve to inform further areas of research on the management of OSA among patients with CVD.

Rationale and design of the randomised Treatment of sleep apnoea Early After Myocardial infarction with Adaptive Servo-Ventilation trial (TEAM-ASV I)

Aims

In acute myocardial infarction (AMI), impaired myocardial salvage and large infarct size result in residual heart failure, which is one of the most important predictors of morbidity and mortality after AMI. Sleep-disordered breathing (SDB) is associated with reduced myocardial salvage index (MSI) within the first 3 months after AMI. Adaptive servo-ventilation (ASV) can effectively treat both types of SDB (central and obstructive sleep apnoea). The Treatment of sleep apnoea Early After Myocardial infarction with Adaptive Servo-Ventilation trial (TEAM-ASV I) will investigate the effects of ASV therapy, added to percutaneous coronary intervention (PCI) and optimal medical management of AMI, on myocardial salvage after AMI.

Methods/design

TEAM ASV-I is a multicentre, randomised, parallel-group, open-label trial with blinded assessment of PCI outcomes. Patients with first AMI and successful PCI within 24 h after symptom onset and SDB (apnoea–hypopnoea index ≥ 15/h) will be randomised (1:1 ratio) to PCI and optimal medical therapy alone (control) or plus ASV (with stratification of randomisation by infarct location; left anterior descending (LAD) or no LAD lesion). The primary outcome is the MSI, assessed by cardiac magnetic resonance imaging. Key secondary outcomes are change of infarct size, left ventricular ejection fraction and B-type natriuretic peptide levels and disease-specific symptom burden at 12 weeks.

Conclusion

TEAM ASV-I will help to determine whether treatment of SDB with ASV in the acute phase after myocardial infarction contributes to more myocardial salvage and healing.

Trial registration

ClinicalTrials.gov, NCT02093377. Registered on March 21, 2014.

The prevalence of sleep-disordered breathing in Northwest Russia: The ARKHsleep study

Sleep-disordered breathing (SDB) is a chronic condition characterized by repeated breathing pauses during sleep. The reported prevalence of SDB in the general population has increased over time. Furthermore, in the literature, a distinction is made between SDB, obstructive sleep apnea (OSA), and "OSA syndrome" (OSAS). Patients with SDB are at increased risk of comorbid cardiovascular diseases (CVDs). The aim of the ARKHsleep study was to assess the prevalence of SDB in general and of OSA and OSAS in particular. A total of 1050 participants aged 30-70 years, who were randomly selected from a population register, were evaluated for the probability of SDB using the Epworth Sleepiness Scale score and body mass index. Sleep was recorded for one night via home sleep apnea testing (Somnolter®). Medical conditions were determined from medical records. Additional data included background characteristics, anthropometric variables, blood pressure, and scores from four questionnaires. The survey sample consisted of 41.2% males and had a mean age of 53.1 ± 11.3 years. The prevalence of mild-to-severe, moderate-to-severe, and severe SDB was 48.9% [45.8-51.9], 18.1% [15.9-20.6], and 4.5% [3.2-5.8], respectively. Individuals reporting snoring or breathing pauses had a higher severity of SDB than individuals free of symptoms. The ARKHsleep study revealed a high burden of both SDB and CVD; however, more large-scale cohort studies and intervention studies are needed to better understand whether the early recognition and treatment of mild SDB with or without symptoms will improve cardiovascular prognosis and/or quality of life.

Interventional techniques to increase implantation success of transvenous phrenic nerve stimulation for central sleep apnea treatment

PURPOSE

Central sleep apnea (CSA) is a highly common comorbidity in heart failure (HF) patients and is known to deteriorate quality of life and prognosis. Effective treatment options are scarce. Transvenous phrenic nerve stimulation (PNS) has been shown to be effective and safe in CSA treatment in HF. However, lead implantation may be difficult or fail due to anatomical or technical challenges. We report novel and innovative approaches applying different interventional techniques to enhance PNS implantation success, allowing otherwise missing CSA treatment.

METHODS

Twenty-seven consecutive HF patients (86% male, mean age: 69 ± 11 years; reduced left ventricular ejection fraction in 16 patients (57%)) were included in this study who were unable to tolerate or had contraindications for mask-based therapy. We evaluated PNS total implantation success, procedural characteristics, and feasibility and success rates of intravascular interventions to facilitate PNS lead implantation in otherwise ineffective procedures.

RESULTS

Seven lead implantation attempts (24%) required additional intravascular interventional action to facilitate successful implantation, mainly consisting of balloon angioplasties to allow optimal PNS lead placement. Two procedures remained unsuccessful and two patients underwent a second procedure due to stimulation side effects and lead fracture respectively. All over, no complications resulted from application of interventional techniques to achieve a 93% implantation success rate.

CONCLUSION

Transvenous PNS lead placement for CSA treatment can be difficult and challenging. However, interventional intravascular techniques markedly increase implantation success and thereby allow application of this therapy for effective CSA treatment in most patients without additional complications.

Central Sleep Apnoea and Arrhythmogenesis After Myocardial Infarction-The CESAAR Study

The prevalence of sleep disordered breathing (SDB) after acute myocardial infarction (AMI) is high. However, little is known about predominant SDB type and the impact of SDB severity on arrhythmogenesis. We conducted a prospective single-center observational study and performed an unattended sleep study and Holter monitoring within 10 days after AMI, and an unattended sleep study 11.3 months after AMI. All patients were included from the Department of Cardiology at the University Hospital Schleswig-Holstein, Lübeck, Germany. A total of 202 subjects with AMI (73.8% with ST-elevation; 59.8 years; 73.8% male) were included. The mean BMI was 27.8 kg/m² and the mean neck/waist circumference was 41.7/103.3 cm. The mean left ventricular ejection fraction was 56.6%. The SDB prevalence defined as apnoea-hypopnea-index (AHI) ≥ 5/h was 66.7% with 44.9% having central (CSA), and 21.8% obstructive sleep apnoea (OSA). The mean AHI was 13.8 1/h. In 10.2% nsVT was detected in the Holter monitoring. AI >23/h was independently associated with higher risk of nsVT in the subacute AMI period. SDB is highly prevalent and CSA a predominant type of SDB in the subacute phase after uncomplicated AMI treated with modern revascularization procedures and evidence-based pharmacological therapy. Severe SDB is independently associated with higher risk for nsVT in the subacute AMI period and its course should be monitored as it can potentially have a negative impact on relevant outcomes of AMI patients. Further prospective studies are needed to assess long-term follow up of SDB after AMI and its impact on mortality and morbidity.

Obstructive Sleep Apnea in Children and Adolescents and the Risk of Major Adverse Cardiovascular Events: A Nationwide Cohort Study in Taiwan

STUDY OBJECTIVES

This study has investigated the risk of major adverse cardiovascular events (MACEs), including acute myocardial infarction, coronary artery disease, peripheral artery disease, and acute stroke, among children and adolescents (age younger than 20 years) with obstructive sleep apnea (OSA).

METHODS

In this study, the population-based National Health Insurance Research Database of Taiwan was used to identify patients in whom OSA had been first diagnosed between 2000 and 2015. Children and adolescents with OSA (n = 6,535) were included with 1:3 ratio by age, sex, and index year of control participants without OSA (n = 19,605). The Cox proportional regression model was used to evaluate the risk of MACEs in this cohort study.

RESULTS

After a 15-year follow-up, the incidence rate of MACEs was higher in the OSA cohort when compared with the non-OSA control cohort (15.97 and 8.20 per 100,000 person-years, respectively). After adjusting for covariates, the risk of MACEs among children and adolescents with OSA was still significantly higher (hazard ratio = 2.050; 95% confidence interval = 1.312-3.107; P = .010). No MACEs were found in the children and adolescents with OSA who received continuous airway positive pressure treatment or pharyngeal surgery.

CONCLUSIONS

This study found a significantly higher risk of MACEs in children and adolescents with OSA. These findings strongly suggest that clinicians should provide careful follow-up and medical treatment for children and adolescents with OSA.