Left ventricular hypertrophy is a common echocardiographic abnormality in severe obstructive sleep apnea and reverses with nasal continuous positive airway pressure

Analysis of QRS complex morphology in children and adolescents with obstructive sleep apnea syndrome

Obstructive sleep apnea syndrome (OSAS) leads to many cardiovascular, neurologic, metabolic, and neurocognitive consequences. Conduction deficits, deviations in electrical axis, and changes in QRS morphology reflect the impairments in cardiac muscle activity and underlie the cardiovascular complications of OSAS. Here we aimed to determine the relationship between OSAS and changes in the cardiac conduction system in children and adolescents. During the 6-month duration of the study, all children having the diagnosis of OSAS in Sleep and Disorders Unit following a full-night polysomnography (PSG) were consecutively evaluated. ECGs were performed and analyzed in the Division of Pediatric Cardiology, Department of Pediatrics. The maximum spatial vector size (QRSmax), QRS electrical axis (EA), left and right ventricular hypertrophy, and the presence of fragmented QRS (fQRS) or prolonged R or S wave were examined in detail. A total of 17 boys with OSAS and 13 healthy boys participated in the study. The mean QRSmax and the QRSmax on V5 derivative were significantly lower in the patient group compared to those in the control group (p = 0.011 and p = 0.017, respectively). EA was similar between the two groups. While none of the patients with OSAS nor the control group had left ventricular hypertrophy, only one boy with OSAS had right ventricular hypertrophy according to ECG-derived analysis. The percentage of fQRS or notched R or S waves was significantly higher in patients with OSAS compared to healthy controls (p = 0.035), especially in children below the age of 5 years (p = 0.036).  Conclusion: This study demonstrated that male children and adolescents with OSAS have a combination of QRS complex changes characterized by low QRS voltages, and increased frequency of fragmented QRS. These findings reflect that the electrical remodeling and structural remodeling of the myocardium are considerably affected by OSAS in children and adolescents, leading to ventricular changes and intraventricular conduction problems. What is Known: • Pediatric obstructive sleep apnea syndrome (OSAS) characterized by recurrent intermittent hypoxemia, hypercapnia, and sleep fragmentation results in sympathetic nervous system activation, increased inflammation, and hypoxic endothelial dysfunction. When left untreated, OSAS leads to many cardiovascular, neurologic, metabolic and neurocognitive consequences, and also to sudden infant death syndrome in young children, probably due to the involvement of the cardiac conduction system. What is New: • This study demonstrated that mean QRSmax was significantly lower in male children and adolescents with OSAS, reflecting the structural and electrical remodeling of the myocardium, and one boy with OSAS had RVH according to ECG-derived analysis. The percentage of fQRS or notched R or S waves was much higher in boys with OSAS, especially in children below the age of five years. These finding showed that myocardium was considerably affected to impair the intraventricular conduction in younger children with OSAS.

Obstructive sleep apnea and hypertension-mediated organ damage in nonresistant and resistant hypertension

The potential role of obstructive sleep apnea (OSA) in hypertension-mediated organ damage (HMOD) may be influenced by the presence of resistant hypertension (RH). Herein, we enrolled patients with hypertension from a tertiary center for clinical evaluation and performed a sleep study to identify OSA (apnea-hypopnea index ≥15 events/h) and a blinded analysis of four standard HMOD parameters (left ventricular hypertrophy [LVH], increased arterial stiffness [≥10 m/s], presence of retinopathy, and nephropathy). RH was diagnosed based on uncontrolled blood pressure (BP) (≥140/90 mmHg) despite concurrent use of at least three antihypertensive drug classes or controlled BP with concurrent use of ≥4 antihypertensive drug classes at optimal doses. To avoid the white-coat effect, ambulatory BP monitoring was performed to confirm RH diagnosis. One-hundred patients were included in the analysis (mean age: 54 ± 8 years, 65% females, body mass index: 30.4 ± 4.5 kg/m²). OSA was detected in 52% of patients. Among patients with non-RH (n = 53), the presence of OSA (52.8%) was not associated with an increased frequency of HMOD. Conversely, among patients with RH, OSA (51.1%) was associated with a higher incidence of LVH (RH-OSA,61%; RH + OSA,87%; p = 0.049). Logistic regression analysis using the total sample revealed that RH (OR:7.89; 95% CI:2.18-28.52; p = 0.002), systolic BP (OR:1.04; 95% CI:1.00-1.07; p = 0.042) and OSA (OR:4.31; 95% CI:1.14-16.34; p = 0.032) were independently associated with LVH. No significant association was observed between OSA and arterial stiffness, retinopathy, or nephropathy. In conclusion, OSA is independently associated with LVH in RH, suggesting a potential role of OSA in RH prognosis.

International Consensus Statement on Obstructive Sleep Apnea

BACKGROUND

Evaluation and interpretation of the literature on obstructive sleep apnea (OSA) allows for consolidation and determination of the key factors important for clinical management of the adult OSA patient. Toward this goal, an international collaborative of multidisciplinary experts in sleep apnea evaluation and treatment have produced the International Consensus statement on Obstructive Sleep Apnea (ICS:OSA).

METHODS

Using previously defined methodology, focal topics in OSA were assigned as literature review (LR), evidence-based review (EBR), or evidence-based review with recommendations (EBR-R) formats. Each topic incorporated the available and relevant evidence which was summarized and graded on study quality. Each topic and section underwent iterative review and the ICS:OSA was created and reviewed by all authors for consensus.

RESULTS

The ICS:OSA addresses OSA syndrome definitions, pathophysiology, epidemiology, risk factors for disease, screening methods, diagnostic testing types, multiple treatment modalities, and effects of OSA treatment on multiple OSA-associated comorbidities. Specific focus on outcomes with positive airway pressure (PAP) and surgical treatments were evaluated.

CONCLUSION

This review of the literature consolidates the available knowledge and identifies the limitations of the current evidence on OSA. This effort aims to create a resource for OSA evidence-based practice and identify future research needs. Knowledge gaps and research opportunities include improving the metrics of OSA disease, determining the optimal OSA screening paradigms, developing strategies for PAP adherence and longitudinal care, enhancing selection of PAP alternatives and surgery, understanding health risk outcomes, and translating evidence into individualized approaches to therapy.

Upregulation of Reg IV and Hgf mRNAs by Intermittent Hypoxia via Downregulation of microRNA-499 in Cardiomyocytes

Sleep apnea syndrome (SAS) is characterized by recurrent episodes of oxygen desaturation and reoxygenation (intermittent hypoxia [IH]), and is a risk factor for cardiovascular disease (CVD) and insulin resistance/Type 2 diabetes. However, the mechanisms linking IH stress and CVD remain elusive. We exposed rat H9c2 and mouse P19.CL6 cardiomyocytes to experimental IH or normoxia for 24 h to analyze the mRNA expression of several cardiomyokines. We found that the mRNA levels of regenerating gene IV (Reg IV) and hepatocyte growth factor (Hgf) in H9c2 and P19.CL6 cardiomyocytes were significantly increased by IH, whereas the promoter activities of the genes were not increased. A target mRNA search of microRNA (miR)s revealed that rat and mouse mRNAs have a potential target sequence for miR-499. The miR-499 level of IH-treated cells was significantly decreased compared to normoxia-treated cells. MiR-499 mimic and non-specific control RNA (miR-499 mimic NC) were introduced into P19.CL6 cells, and the IH-induced upregulation of the genes was abolished by introduction of the miR-499 mimic, but not by the miR-499 mimic NC. These results indicate that IH stress downregulates the miR-499 in cardiomyocytes, resulting in increased levels of Reg IV and Hgf mRNAs, leading to the protection of cardiomyocytes in SAS patients.

Downregulation of the Cd38-Cyclic ADP-Ribose Signaling in Cardiomyocytes by Intermittent Hypoxia via Pten Upregulation

Sleep apnea syndrome (SAS) is characterized by recurrent episodes of oxygen desaturation and reoxygenation (intermittent hypoxia, IH), and it is a risk factor for cardiovascular disease (CVD) and insulin resistance/type 2 diabetes. However, the mechanisms linking IH stress and CVD remain elusive. We exposed rat H9c2 and mouse P19.CL6 cardiomyocytes to experimental IH or normoxia for 24 h to analyze the mRNA expression of the components of Cd38-cyclic ADP-ribose (cADPR) signaling. We found that the mRNA levels of cluster of differentiation 38 (Cd38), type 2 ryanodine receptor (Ryr2), and FK506-binding protein 12.6 (Fkbp12.6) in H9c2 and P19.CL6 cardiomyocytes were significantly decreased by IH, whereas the promoter activities of these genes were not decreased. By contrast, the expression of phosphatase and tensin homolog deleted from chromosome 10 (Pten) was upregulated in IH-treated cells. The small interfering RNA for Pten (siPten) and a non-specific control RNA were introduced into the H9c2 cells. The IH-induced downregulation of Cd38, Ryr2, and Fkbp12.6 was abolished by the introduction of the siPten, but not by the control RNA. These results indicate that IH stress upregulated the Pten in cardiomyocytes, resulting in the decreased mRNA levels of Cd38, Ryr2, and Fkbp12.6, leading to the inhibition of cardiomyocyte functions in SAS patients.

Is myocardial strain an early marker of systolic dysfunction in obstructive sleep apnoea? Findings from a meta-analysis of echocardiographic studies

AIM

We investigated the association between obstructive sleep apnoea (OSA) and subclinical systolic dysfunction through a meta-analysis of echocardiographic studies that provided data on left ventricular (LV) mechanics as assessed by global longitudinal strain (GLS).

DESIGN

The PubMed, OVID-MEDLINE, and Cochrane library databases were systematically analyzed to search English-language articles published from inception to 31 December 2021. Studies were detected by using the following terms: 'obstructive sleep apnea', 'sleep quality', 'sleep disordered breathing', 'cardiac damage', 'left ventricular hypertrophy', 'systolic dysfunction', 'global longitudinal strain', 'left ventricular mechanics', 'echocardiography' and 'speckle tracking echocardiography'.

RESULTS

The meta-analysis included 889 patients with OSA and 364 non-OSA controls from 12 studies. Compared with controls, GLS was significantly reduced in the pooled OSA group (SMD -1.24 ± 0.17, CI: -1.58 to -0.90, P  < 0.0001), as well as in the normotensive OSA subgroup (SMD: -1.17 ± 0.12 CI:-1.40 to -0.95, P  < 0.0001). Similar findings were obtained in sub-analyses performed separately in mild, moderate and severe OSA. This was not the case for LV ejection fraction (LVEF) (i.e. comparisons between controls vs. mild OSA, mild vs. moderate OSA, moderate vs. severe OSA).

CONCLUSION

GLS is impaired in patients with OSA (independently from hypertension), worsening progressively from mild to moderate and severe forms, thus allowing to identify subclinical alterations of the systolic function not captured by LVEF. Therefore, myocardial strain assessment should be implemented systematically in the OSA setting to timely detect systolic dysfunction.

Association of Preoperative Sleep-Disordered Breathing With Functional Status After Septal Myectomy for Obstructive Hypertrophic Cardiomyopathy

Background

Sleep-disordered breathing (SDB) is a risk factor for heart failure symptoms in patients with hypertrophic cardiomyopathy (HCM). However, the relationship between preoperative SDB and postoperative functional status after septal myectomy (SM) is unknown. In this study, we investigated the association of preoperative SDB with late self-reported health status among patients undergoing SM for obstructive HCM.

Methods

Prior to SM, an overnight pulse oximetry test was used to measure oxygen desaturation index (ODI), which indicates the average number of desaturation episodes with at least 4% of drops in oxygen level from baseline per hour of sleep. Patients reported postoperative function through a questionnaire-based survey completed 3-5 years following SM.

Results

We analyzed 264 patients who underwent transaortic SM from November 2005 through April 2016. On predischarge transthoracic echocardiography post-procedure, no significant difference was present in the extent of mitral valve regurgitation (P = 0.524), left ventricular outflow tract gradient (P = 0.405), or septal thickness (P = 0.744) related to ODI. At 3 to 5 years after their operation, 236 patients (89%) reported good or excellent health. Approximately 18% (n = 48) and 8% (n = 22) of the cohort continued to experience exertional dyspnea and chest tightness, respectively, on walking 2 blocks or less. A greater ODI was not an independent predictor of worse health status or residual symptoms.

Conclusions

Relief of left ventricular outflow tract obstruction in patients with obstructive HCM improves symptoms, with 89% of patients reporting good or excellent health. Preoperative SDB is not significantly associated with late functional status after septal myectomy.

Cardiac consequences of intermittent hypoxia: a matter of dose? A systematic review and meta-analysis in rodents

Aim

Intermittent hypoxia (IH) is considered to be a major contributor to obstructive sleep apnoea-related cardiovascular consequences. The present meta-analysis aimed to assess the effects of IH on cardiac remodelling, function and infarct size after myocardial ischaemia across different rodent species and IH severities.

Methods and results

Relevant articles from PubMed, Embase and Web of Science were screened. We performed a random effect meta-analysis to assess the effect of IH on myocardium in rodents by using standardised mean difference (SMD). Studies using rodents exposed to IH and outcomes related to cardiac remodelling, contractile function and response to myocardial ischaemia–reperfusion were included. 5217 articles were screened and 92 were included, demonstrating that IH exposure induced cardiac remodelling, characterised by cardiomyocyte hypertrophy (cross-sectional area: SMD=2.90, CI (0.82–4.98), I²=94.2%), left ventricular (LV) dilation (LV diameter: SMD=0.64, CI (0.18–1.10), I²=88.04%), interstitial fibrosis (SMD=5.37, CI (3.22–7.53), I²=94.8) and apoptosis (terminal deoxynucleotidyl transferase dUTP nick end labelling: SMD=6.70, CI (2.96–10.44), I²=95.9). These structural changes were accompanied by a decrease in LV ejection fraction (SMD=−1.82, CI (−2.52–−1.12), I²=94.22%). Importantly, most of the utilised IH protocols mimicked extremely severe hypoxic disease. Concerning infarct size, meta-regression analyses highlighted an ambivalent role of IH, depending on its severity. Indeed, IH exposure with inspiratory oxygen fraction (F_IO2) <7% was associated with an increase in infarct size, whereas a reduced infarct size was reported for F_IO2 levels above 10%. Heterogeneity between studies, small study effect and poor reporting of methods in included articles limited the robustness of the meta-analysis findings.

Conclusion

This meta-analysis demonstrated that severe IH systematically induces cardiac remodelling and contractile dysfunction in rodents, which might trigger or aggravate chronic heart failure. Interestingly, this meta-analysis showed that, depending on stimulus severity, IH exhibits both protective and aggravating effects on infarct size after experimental ischaemia–reperfusion procedures.

This meta-analysis shows that IH induces cardiac remodelling and contractile dysfunction in rodents, independently of IH characteristics. Conversely, the dual response to myocardial ischaemia–reperfusion seems to be related to IH intensity and duration.https://bit.ly/3rdnR32

Mandibular advancement device treatment and reverse left ventricular hypertrophic remodeling in patients with obstructive sleep apnea

STUDY OBJECTIVES

Obstructive sleep apnea (OSA) is associated with cardiovascular comorbidities such as left ventricular (LV) hypertrophy. Whether OSA is an independent etiological factor for this hypertrophic remodeling is yet unknown. Continuous positive airway pressure partially reverses this hypertrophy, but data regarding the effect of mandibular advancement devices on LV remodeling are scarce. The aim of this prospective trial is to evaluate the effect of mandibular advancement device therapy on LV geometry and function in patients with OSA.

METHODS

At baseline and 6-month follow-up, participants underwent a home sleep apnea test, 24-hour ambulatory blood pressure monitoring and a 2-dimensional Doppler and tissue Doppler echocardiography.

RESULTS

Sixty-three patients (age: 49 ± 11 years; body mass index: 27.0 ± 3.4 kg/m²; baseline apnea-hypopnea index home sleep apnea test: 11.7 [8.2; 24.9] events/h) completed the 6-month follow-up visit. Overall, blood pressure values and parameters of LV function were within normal ranges at baseline and did not change under mandibular advancement device therapy. In contrast, the interventricular septum thickness was at the upper limits of normal at baseline and showed a significant decrease at 6-month follow-up (11.1 ± 2.1 mm vs 10.6 ± 2.0 mm, P = .03). This significant improvement is only found in responders but not in nonresponders. There was no correlation between the decrease of interventricular septum thickness and the change in blood pressure.

CONCLUSIONS

In mildly obese, normotensive patients with OSA we observed significant reverse hypertrophic remodeling after 6 months of successful mandibular advancement device therapy, with maintained normotensive systemic blood pressure. This suggests that OSA is an independent factor in the pathophysiology of LV hypertrophy in these patients.

CLINICAL TRIAL REGISTRATION

Registry: ClinicalTrials.gov; Name: Evaluation of the Cardiovascular Effects of the MAS in the Treatment of Obstructive Sleep Apnea; URL: https://clinicaltrials.gov/ct2/show/NCT02320877; Identifier: NCT02320877.

CITATION

Dieltjens M, Vanderveken OM, Shivalkar B, et al. Mandibular advancement device treatment and reverse left ventricular hypertrophic remodeling in patients with obstructive sleep apnea. J Clin Sleep Med. 2022;18(3):903-909.

Obstructive sleep apnea and cardiovascular comorbidity: common pathophysiological mechanisms to cardiovascular disease

Obstructive sleep apnea (OSA) is associated with many cardiovascular and metabolic diseases. Sleep apnea causes intermittent hypoxemia, chest pressure fluctuations and a reaction from the cerebral cortex in the form of a short awakening during sleep (EEG-activation). The consequences of pathological pathways are studied in experimental models involving cell cultures, animals, and healthy volunteers. At present, the negative impact of intermittent hypoxemia on a variety of pathophysiological disorders of the heart and blood vessels (vascular tone fluctuations, thickening of the intimamedia complex in the vascular wall, direct damaging effect on the myocardium) has a great evidence base. Two other pathological components of OSA (pressure fluctuations and EEG-activation) can also affect cardiovascular system, mainly affecting the increase in blood pressure and changing cardiac hemodynamics. Although these reactions are considered separately in the review, with the development of sleep apnea they occur sequentially and are closely interrelated. As a result, these pathological pathways trigger further pathophysiological mechanisms acting on the heart and blood vessels. It is known that these include excessive sympathetic activation, inflammation, oxidative stress and metabolic dysregulation. In many respects being links of one process, these mechanisms can trigger damage to the vascular wall, contributing to the formation of atherosclerotic lesions. The accumulated data with varying degrees of reliability confirm the participation of OSA through these processes in the formation of cardiovascular disorders. There are factors limiting direct evidence of this interaction (sleep deprivation, causing similar changes, as well as the inability to share the contribution of other risk factors for cardiovascular diseases, in particular arterial hypertension, obesity, which are often associated with OSA). It is necessary to continue the study of processes that implement the pathological effect of OSA on the cardiovascular system.

Effects of adenoidectomy or adenotonsillectomy on the cardiovascular system in children: a meta-analysis

OBJECTIVE

Adenoid or adenotonsillar hypertrophy (AATH) causes upper airway obstruction, leading to cardiovascular complications. This meta-analysis was conducted to evaluate the efficacy of adenoidectomy or adenotonsillectomy (AATE) on the cardiovascular system.

METHODS

Using the Cochrane Central Register of Controlled Trials, PubMed, and EMBASE databases, we identified studies involving a comparison of preoperative and postoperative cardiovascular function in children with AATH. The Cochrane Collaboration's Review Manager 5.3 software was used for meta-analysis.

RESULTS

A total of 13 studies with 706 participants were included. The meta-analysis demonstrated a significant reduction in mean pulmonary artery pressure (mPAP) of patients after AATE compared with preoperative values. The left ventricular myocardial function index (LVMPI) and the right ventricular myocardial function index (RVMPI) showed a significant decrease after the operation. Moreover, AATE prominently increased left ventricular ejection time (LVET) and right ventricular ejection time (RVET) and reduced the left ventricular interventricular septum diameter (LVIVSD) and the right ventricular end-diastolic diameter (RVedD). There was no significant difference in mPAP, LVMPI, RVMPI, LVET, RVET, LVIVSD, and RVedD between postoperative patients and healthy children (P  > 0.05).

CONCLUSION

AATE can improve cardiovascular function in pediatric patients with AATH. Specifically, it reduces mPAP and LVMPI/RVMPI in pediatric patients. Furthermore, AATE increases LVET and RVET and reduces LVIVSD and RVedD.

Obstructive sleep apnoea syndrome and left ventricular hypertrophy: a meta-analysis of echocardiographic studies

AIM

We investigated the association between obstructive sleep apnoea (OSA) and subclinical cardiac organ damage through a meta-analysis of echocardiographic studies that provided data on left ventricular hypertrophy (LVH), assessed as a categorical or continuous variable.

DESIGN

The PubMed, OVID-MEDLINE, and Cochrane library databases were systematically analyzed to search English-language articles published from 1 January 2000 to 15 August 2019. Studies were detected by using the following terms: 'obstructive sleep apnea', 'sleep quality', 'sleep disordered breathing', 'cardiac damage', 'left ventricular mass', 'left ventricular hypertrophy', and 'echocardiography'.

RESULTS

Meta-analysis included 5550 patients with OSA and 2329 non-OSA controls from 39 studies. The prevalence of LVH in the pooled OSA population was 45% (CI 35--55%). Meta-analysis of studies comparing the prevalence of LVH in participants with OSA and controls showed that OSA was associated with an increased risk of LVH (OR = 1.70, CI 1.44-2.00, P < 0.001). LV mass was significantly increased in patients with severe OSA as compared with controls (SMD 0.46 ± 0.08, CI 0.29-0.62, P < 0.001) or with mild OSA. This was not the case for studies comparing patients with unselected or predominantly mild OSA and controls (0.33 ± 0.17, CI -0.01 to 0.67, P = 0.057).

CONCLUSION

The present meta-analysis expands previous information on the relationship between OSA and echocardiographic LVH, so far based on individual studies. The overall evidence strongly suggests that the likelihood of LVH increases with the severity of OSA, thus exhibiting a continuous relationship.

Association Between Intermittent Hypoxia and Left Ventricular Remodeling in Patients With Obstructive Sleep Apnea-Hypopnea Syndrome

The present study was undertaken to examine the association between intermittent hypoxia and left ventricular (LV) remodeling and explore which parameter of intermittent hypoxia is most relevant to LV remodeling in patients with obstructive sleep apnea-hypopnea syndrome (OSAHS). Two hundred eighty six patients underwent polysomnographic examination were enrolled. Based on apnea-hypoxia index (AHI), patients were divided into no, mild, moderate and severe OSAHS groups. Between-group differences in LV remodeling and the association between parameters of intermittent hypoxia and LV remodeling was evaluated. Patients with severe OSAHS were more likely to have hypertension, and higher values of LV mass (LVM) and LVM index (LVMI). In univariate regression analysis, male, body mass index (BMI), systolic and diastolic blood pressure (BP), statins, antihypertensive drugs, creatinine, and parameters of intermittent hypoxia (AHI, obstructive apnea index [OAI], lowest oxygen saturation [LSpO₂], oxygen desaturation index [ODI], time spent below oxygen saturation of 90% [TS90%], and mean nocturnal oxygen saturation [MSpO₂]) were associated with LVMI. After multivariate regression analyses, only male gender, BMI, systolic BP, creatinine, and ODI remained significantly associated with LVMI. Compared to those without LV hypertrophy (LVH), patients with LVH had higher ODI. Compared to patients with normal LV, concentric remodeling and eccentric LVH, those with concentric LVH had higher ODI. In conclusion, intermittent hypoxia was significantly associated with left ventricular remodeling; and among various parameters of intermittent hypoxia, ODI was the most relevant to LV remodeling.

Clinical Characteristics of Hypertensive Patients with Obstructive Sleep Apnoea Syndrome Developing Different Types of Left Ventricular Geometry

Objective

The objective of the study was to compare polygraphic parameters and selected laboratory parameters in patients with obstructive sleep apnoea (OSA) who develop various types of left ventricular (LV) geometry. Material and Methods. The research covered 122 patients with obstructive sleep apnoea and coexisting effectively treated systemic hypertension (95 men, 27 women, average age: 54 ± 10.63). Overnight polygraphy, echocardiography, carotid artery ultrasonography, and laboratory measurements were performed. The patients were classified into four groups, depending on LV geometry. Group 1 comprised patients with normal LV geometry, group 2 included those with LV concentric remodelling. Group 3 and group 4 were patients with LV hypertrophy, concentric or eccentric, respectively.

Results

The most frequent type of LV geometry in the examined population was eccentric hypertrophy (36%). The highest average values of BMI and T-Ch were observed in the group of patients with concentric remodelling (group 2). The most severe respiratory disorders were found in the group of patients developing LV concentric hypertrophy (group 3); however, these differences were not statistically significant in comparison to other groups. Patients with LV eccentric hypertrophy had significantly decreased LV ejection fraction (p = 0.0008).

Conclusions

LV eccentric hypertrophy is the most frequent type of LV geometry in OSA patients. Patients with severe sleep-disordered breathing are more likely to develop concentric hypertrophy, while concentric remodelling occurs more frequently among OSA patients with other coexisting conditions, such as obesity or lipid-related disorders.

Left Ventricular Geometrical Changes in Severely Obese Adolescents: Prevalence, Determinants, and Clinical Implications

Left ventricular hypertrophy (LVH) is independently associated with a higher risk of cardiovascular morbidity and mortality in adults. Adiposity is a risk factor for LVH, independent of blood pressure. Potential causes of this nonhemodynamic pathogenesis identified in adults include adverse body fat distribution, insulin resistance, dyslipidemia, and obstructive sleep apnea syndrome (OSA). In severely obese adolescents, the determinants of obesity-induced changes in left ventricular structure are poorly characterized. Cardiac ultrasonographic, demographic, anthropometric, and comorbidity-related data were prospectively collected in adolescents with severe obesity refractory to conservative treatment who presented for surgical therapy. Differences between adolescents with LVH and without LVH were evaluated using independent samples t, chi-square, or Fisher's exact test. Multivariable linear regression analysis was performed to evaluate associations with left ventricular structural changes, corrected for body mass index (BMI) z score. Forty-three patients entered analysis, of whom 24 (55.8%) showed LVH. The most common geometrical change was eccentric LVH (eLVH), occurring in 21 subjects (48.8%). Demographic and anthropometric variables did not differ between patients with and without LVH. Independent of BMI z score, left ventricular mass index was significantly associated with apnea-hypopnea index (AHI) (regression parameter B = 0.8; 95% CI 0.3 to 1.2). Interventricular septum thickness (IVST) was significantly associated with HOMA-IR values (B = 0.1; 95% CI 0.04 to 0.2), HDL-cholesterol (B = - 1.2; 95% CI - 2.2 to 0.1), and triglyceride levels (B = 0.5; 95% CI 0.001 to 0.9). LVH, especially eLVH, is highly prevalent amongst severely obese adolescents. Adverse changes in cardiac structure, increased IVST in particular, are independently associated with several nonhemodynamic comorbidities that are common in this population, namely OSA, insulin resistance, and dyslipidemia.

Association Between Sleep Disordered Breathing and Left Ventricular Function: A Cross-Sectional Analysis of the ECHO-SOL Ancillary Study

BACKGROUND

Prior studies have found that sleep-disordered breathing (SDB) is common among those with left ventricular (LV) dysfunction and heart failure. Few epidemiological studies have examined this association, especially in US Hispanic/Latinos, who may be at elevated risk of SDB and heart failure.

METHODS

We examined associations between SDB and LV diastolic and systolic function using data from 1506 adults aged 18 to 64 years in the Hispanic Community Health Study/Study of Latinos ECHO-SOL Ancillary Study (2011-2014). Home sleep testing was used to measure the apnea-hypopnea index, a measure of SDB severity. Echocardiography was performed a median of 2.1 years later to quantify LV diastolic function, systolic function, and structure. Multivariable linear regression was used to model the association between apnea-hypopnea index and echocardiographic measures while accounting for the complex survey design, demographics, body mass, and time between sleep and echocardiographic measurements.

RESULTS

Each 10-unit increase in apnea-hypopnea index was associated with 0.2 (95% CI, 0.1-0.3) lower E', 0.3 (0.1-0.5) greater E/E' ratio, and 1.07-fold (1.03-1.11) higher prevalence of diastolic dysfunction as well as 1.3 (0.3-2.4) g/m2 greater LV mass index. These associations persisted after adjustment for hypertension and diabetes mellitus. In contrast, no association was identified between SDB severity and subclinical markers of LV systolic function.

CONCLUSIONS

Greater SDB severity was associated with LV hypertrophy and subclinical markers of LV diastolic dysfunction. These findings suggest SDB in Hispanic/Latino men and women may contribute to the burden of heart failure in this population.

Sleep Disordered Breathing in Hypertrophic Cardiomyopathy-Current State and Future Directions

Hypertrophic cardiomyopathy (HCM) is the most common inherited cardiomyopathy and sleep disordered breathing (SDB) is a treatable risk factor that has been seen to occur concurrently, and is known to propagate mortality and morbidity in a number of cardiovascular disease states including heart failure, and indeed hypertrophic cardiomyopathy. In this review, we summarize past studies that explored the simultaneous occurrence of HCM and SDB, and the pathophysiology of SDB in relation to heart failure, arrhythmias, cardiac ischemia and pulmonary hypertension in HCM. The current therapeutic modalities, with the effect of obstructive sleep apnea (OSA) treatment on HCM, are then discussed along with potential future directions.

Mandibular Advancement Devices Prevent the Adverse Cardiac Effects of Obstructive Sleep Apnea-Hypopnea Syndrome (OSAHS)

Although considerable research highlights the interactions between obstructive sleep apnea-hypopnea syndrome (OSAHS) and cardiovascular diseases, the effect of mandibular advancement device (MAD) treatment on cardiovascular complications in OSAHS patients remains unclear. We evaluated the effect of OSAHS treatment with MADs on the myocardium. All methods in this study were in accordance with relevant guidelines and regulations of the medical ethics committee in Hospital of Stomatology, Hebei Medical University approved the work. Thirty New Zealand rabbits were randomized into three groups: the control group, Group OSAHS, and Group MAD. Hydrophilic polyacrylamide gel was injected into the soft palate of the rabbits to induce OSAHS. In Group MAD, a MAD was positioned after OSAHS induction. All animals were induced to sleep in a supine position for 4–6 h/day for 8 weeks. Echocardiography was used to determine the structure and function of the heart. The histological changes were detected by optical microscopy and transmission electron microscopy (TEM). The levels of ET-1(endothelin-1) and Ang II (Angiotensin II) in the plasma were measured by an enzyme-linked immunosorbent assay (ELISA). The expression of ET-1 mRNA in heart tissue was detected by RT-PCR. Histological abnormalities, left ventricular hypertrophy, and left ventricular dysfunctions were demonstrated in Group OSAHS, and the abnormities were rescued with MAD treatment. Higher levels of plasma ET-1 and Ang II and elevated expression of ET-1 mRNA in cardiac tissue were detected in Group OSAHS compared with Group MAD and the control group. The blood oxygen saturation was negatively correlated with the levels of ET-1 and Ang II. OSAHS-induced elevated levels of ET-1 and Ang II may be attributed to myocardial structural abnormalities and dysfunction. Early treatment of MADs may play an important role in preventing myocardial damage in OSAHS rabbit model.

Serum apoptotic marker M30 is positively correlated with early diastolic dysfunction in adolescent obesity

Purpose

Obesity in adolescence has been shown to be related to cardiac geometric and functional changes. Cardiac dysfunction in adults with obesity could be attributed to chronic low-grade inflammation, apoptosis of cardiomyocyte, and glucose metabolic disorder. The aforementioned association in adolescents with obesity have never been well studied. Our aim was to determine the types of cardiac dysfunction in adolescents with obesity and survey the association between cardiac dysfunction and chronic low-grade inflammation, apoptosis, and glucose dysregulation in adolescents with obesity.

Methods

Adolescents aged between 10 and 20 years were enrolled in this study. Body mass index, waist-to-hip ratio, blood pressure, glucose metabolism, and high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), tumor necrosis factor-a (TNF-α), and apoptosis marker M30 levels were measured. Echocardiographic indices were also measured. The association between serum biomarkers and echocardiographic function parameters was analyzed.

Results

Diastolic dysfunction was the major finding in the cardiac functional assessment. The main changes in glucose metabolism were elevated C-peptide level and insulin resistance. Hs-CRP, IL-6, and M30 levels also increased with adolescent obesity. M30 was the major biomarker that was highly correlated to diastolic dysfunction indices in adolescents with obesity.

Conclusions

Diastolic dysfunction was the main change in adolescent obesity. Insulin resistance, apoptotic marker M30, hs-CRP, and IL-6 were all elevated in adolescents with obesity. Only M30 was related to indices of left ventricular diastolic dysfunction among adolescents with obesity, rather than inflammation or insulin resistance.

Matrix metalloproteinases as possible biomarkers of obstructive sleep apnea severity - A systematic review

Obstructive sleep apnea is an underdiagnosed sleep-related breathing disorder affecting millions of people. Recurrent episodes of apnea/hypopnea result in intermittent hypoxia leading to oxidative stress. Obstructive sleep apnea is considered an independent risk factor for cardiovascular disease but the exact pathophysiology of adverse cardiovascular outcomes of obstructive sleep apnea has not been fully elucidated. Matrix metalloproteinases (MMPs) have been associated with both oxidative stress and cardiovascular diseases. Hypoxic conditions were shown to influence MMP expression, secretion and activity. Moreover, matrix metalloproteinases contribute to ischemia/reperfusion injury. Therefore, action of matrix metalloproteinases can provide a possible molecular mechanism linking obstructive sleep apnea with oxidative stress and cardiovascular disease. The aim of this paper was to review the current evidence of association between matrix metalloproteinases and obstructive sleep apnea with focus on hypoxemia and severity of obstructive sleep apnea.

Obstructive Sleep Apnea in Heart Failure: Review of Prevalence, Treatment with Continuous Positive Airway Pressure, and Prognosis

Obstructive sleep apnea is a sleep-related breathing disorder that has a major impact on cardiovascular function. It has been associated with hypertension, coronary artery disease, cardiac arrhythmias, sudden cardiac death, and heart failure. This review focuses on the relationship between obstructive sleep apnea and heart failure with either reduced or preserved ejection fraction. We discuss the pathophysiology of obstructive sleep apnea, as well as its prevalence, treatment outcomes with continuous positive airway pressure, and prognosis in these 2 distinct types of heart failure. We also identify areas in which further work is needed to improve our understanding of this association in heart failure patients.

Cardiovascular effects of oral appliance therapy in obstructive sleep apnea: A systematic review and meta-analysis

Obstructive sleep apnea (OSA) is associated with increased cardiovascular morbidity and mortality. This study systematically reviews the effects of oral appliance therapy (OAT) on a broad spectrum of cardiovascular outcomes. A literature search was performed up to December 31st 2016. Twenty-five relevant full-text articles were retrieved. Sixteen articles were considered methodologically sufficient, including 11 randomized controlled trials. Pooled data of the RCTs showed significant reductions in daytime systolic and diastolic blood pressure compared to baseline, but no significant reductions in heart rate, except for daytime heart rate when compared to inactive/placebo OAT. OAT and continuous positive airway pressure (CPAP) were equally effective in reducing blood pressure. Studies assessing the effect of OAT on heart rate variability, circulating cardiovascular biomarkers, and endothelial function and arterial stiffness, generally involved small numbers of patients, and were heterogeneous and inconclusive. Studies assessing the effect of OAT on cardiac function showed no effects on echocardiographic outcomes. One observational study showed that OAT was as effective as CPAP in reducing cardiovascular death. It could be speculated that OAT may lead to a reduction in long-term cardiovascular morbidity and mortality in OSA patients. However, further methodologically high quality, longitudinal studies are warranted to address this key question.

The association of sleep disordered breathing with left ventricular remodeling in CAD patients: a cross-sectional study

Background

There is still insufficient knowledge on the potential effect of mild to moderate sleep-disordered breathing (SDB) that is widely prevalent, often asymptomatic, and largely undiagnosed in patients with stable coronary artery disease (CAD). SDB affects 34% of men and 17% of women aged between 30 and 70. The objective of this study was to evaluate the association between SDB and left ventricular (LV) hypertrophy as well as structural remodeling in stable CAD patients.

Methods

The study was based on a cross-sectional design. Echocardiography and polysomnography was performed in 772 patients with CAD and with untreated sleep apnea. All study participants underwent testing by Epworth Sleepiness Scale questionnaire. Their mean age, NYHA and left ventricular ejection fraction were, respectively: 57 ± 9 years, 2.1 ± 0.5 and 51 ± 8%, and 76% were men. Sleep apnea (SA) was defined as an apnea-hypopnea-index (AHI) ≥5 events/h, and, non-SA, as an AHI <5.

Results

Sleep apnea was present in 39% of patients, and a large fraction of those patients had no complaints on excessive daytime sleepiness. The patients with SA were older, with higher body mass and higher prevalence of hypertension. LV hypertrophy (LVH), defined by allometrically corrected (LV mass/height^2.7) gender-independent criteria, was more common among the patients with SA than those without (86% vs. 74%, p < 0.001). The frequency of LVH by wall thickness criteria (interventricular septal thickness or posterior wall thickness ≥ 12 mm: 49% vs. 33%, p < 0.001) and concentric LVH (61% vs. 47%, p = 0.001) was higher in CAD patients with SA. The patients with SA had significantly higher values of both interventricular septal thickness and posterior wall thickness. Multiple logistic regression analysis showed that even mild sleep apnea was an independent predictor for LVH by wall thickness criteria and concentric LVH (OR = 1.5; 95% CI 1.04–2.2 and OR = 1.9; 1.3–2.9 respectively).

Conclusions

We concluded that unrecognized sleep apnea was highly prevalent among patients with stable CAD, and the majority of those patients did not report daytime sleepiness. Mild to moderate sleep apnea was associated with increased LV wall thickness, LV mass, and with higher prevalence of concentric LV hypertrophy independently of coexisting obesity, hypertension, diabetes mellitus or advancing age.

The Role of Obesity in the Development of Left Ventricular Hypertrophy Among Children and Adolescents

Both obesity and hypertension have increased substantially among children over the last several decades. At the same time, mounting evidence has pointed to the role of these and other cardiovascular disease risk factors on the development of end organ damage such as left ventricular hypertrophy in children. While traditionally thought to occur in response to an increased afterload as in systemic hypertension, evidence demonstrates that obesity is associated with left ventricular hypertrophy independent of blood pressure. Both hemodynamic and non-hemodynamic factors contribute to the pathogenesis of obesity-related left ventricular remodeling. However, more contemporary research suggests that adiposity and blood pressure have a greater effect on left ventricular geometry when present together than when present alone. Normalization of left ventricular mass in obese hypertensive individuals requires achievement of both normotension and weight loss. Additional strategies are needed to promote the cardiovascular health of children, with greater emphasis placed on obesity prevention.

Acute and Chronic Effects of Noninvasive Ventilation on Left and Right Myocardial Function in Patients with Obstructive Sleep Apnea Syndrome: A Speckle Tracking Echocardiographic Study

BACKGROUND

In patients with obstructive sleep apnea syndrome (OSAS), repetitive hypoxia due to sleep-induced apnea adversely affects the interaction between myocardial oxygen demand and supply, resulting in the development of subclinical cardiac dysfunction. The purpose of the study was to analyze the different involvement of left and right heart myocardial function in patients with OSAS treated with noninvasive ventilation (NIV).

METHODS

Conventional Doppler echocardiography, Doppler myocardial imaging (DMI), and two-dimensional speckle tracking echocardiography (2DSTE) of left (LV) and right ventricular (RV) longitudinal and right atrial (RA) deformation were performed in 55 patients with OSAS undergoing NIV (M/F 38/17; mean age 67.8 ± 11.2 years). LV and RV global longitudinal strain (GLS) was calculated by averaging local strain along the entire right and left ventricle, before and during NIV, and after 6 months of nocturnal NIV therapy.

RESULTS

LV morphology was comparable before and during NIV, whereas LV ejection fraction and LV DMI early diastolic peak velocity were significantly improved in patients with OSAS during NIV, as was LV regional peak myocardial strain (P < 0.001). RV diameters were slightly increased in patients with OSAS during ventilation, whereas pulmonary artery systolic pressure (PASP), RV GLS, and regional peak myocardial RV strain were significantly reduced during ventilation (P < 0.0001). RA transverse diameters and RA area were also slightly increased during NIV, whereas RA lateral wall strain was reduced (P < 0.001). Acute RV myocardial impairment completely reversed at follow-up, with a decrease in PASP and subsequent increase in both RV and RA myocardial performance.

CONCLUSIONS

Conventional 2DSTE is a useful tool for assessing left and right heart morphology and myocardial deformation in patients with OSAS and for monitoring both acute and chronic effects of NIV.

Association between Obstructive Sleep Apnea and Left Ventricular Structure by Age and Gender: the Multi-Ethnic Study of Atherosclerosis

STUDY OBJECTIVES

The presence and severity of obstructive sleep apnea (OSA) are associated with impaired left ventricular (LV) structure and function. Our goal was to quantify the associations between LV systolic function and mass with severity of OSA in an ethnically diverse cohort, assessing variations by age and sex.

METHODS

We conducted a cross-sectional analysis of data from 1,412 racially/ethnically diverse participants across 6 US communities from the Multi-Ethnic Study of Atherosclerosis who underwent both overnight polysomnography and cardiac magnetic resonance imaging from 2010-2012. We evaluated the association between the obstructive apnea-hypopnea index (AHI) by clinical category (< 5, 5-15, 15-30, 30-50, > 50) and secondary measures of sleep apnea with the outcomes left ventricular (LV) mass adjusted for height, LV mass/volume ratio, and LV ejection fraction.

RESULTS

After adjusting for potential confounders and mediators, LV mass was significantly increased with increasing AHI category for subjects age 65 y or younger (β = 1.84 ± 0.47 g/m, P = 0.0001). The association between the AHI and LV mass appeared stronger in whites and Chinese compared to blacks and Hispanics, although interaction terms were not statistically significant. Additionally, while both LV mass and LV mass/volume ratio were significantly associated with hypoxia, ejection fraction was not associated with any OSA severity index. Comparable associations were observed in men and women.

CONCLUSIONS

Independent of confounders, higher levels of AHI are significantly associated with increased LV mass in both men and women younger than 65 y from a community-based cohort.

Sleep Disordered Breathing: Hypertension and Cardiac Structure and Function

Obstructive sleep apnea (OSA) is a common form of sleep disordered breathing and has a relatively high prevalence in the general population. The frequency and severity of OSA is associated with age, male sex, and obesity, and OSA has been linked to cardiovascular complications and death. Importantly, OSA has a strong association with both prevalent and incidental hypertension and has a particularly high prevalence in patients with resistant hypertension. In these patients, CPAP and other OSA-directed treatments have been proposed as therapy to help control blood pressure (BP), especially in patients who have not attained optimal BP control despite maximum pharmacological therapy. OSA has also been associated with alterations in cardiac structure and function, although most studies are small and highly limited in study design. Existing data suggest an association between OSA greater left ventricle (LV) mass and hypertrophy that appears independent of confounders including hypertension and obesity. Although less clear and more controversial, OSA severity has been linked to LV systolic and diastolic function, pulmonary hypertension, and right ventricular hypertrophy. Further studies are needed to confirm the potential causal role of OSA in these observed associations with cardiac abnormalities.

Evaluation of pediatric voice handicap index and pediatric voice related quality of life before and after adenotonsillectomy in pediatric population

OBJECTIVE

To study changes in Pediatric Voice Handicap Index (PVHI) and Pediatric Voice Related Quality of Life (PVRQOL) before and after adenotonsillectomy in short term follow up.

METHODS

Quasi-experimental (before and after study). Eighty-six children aged 3-13 years (58 boys, 28 girls) with adenotonsillar problems (whether with obstructive or infectious surgical indications) who were admitted for adenotonsillectomy procedure. Parents of children were asked to complete PVHI and PVRQOL questionnaires prior to surgery and 1 month after it.

RESULTS

Reliability of the PVRQOL and PVHI was established by evaluation of Cronbach α value. Cronbach α for PVHI was 0.92 and for PVRQOL it was 0.83. Preoperative values for the PVHI were: mean±SD; 14.39±14.65. Preoperative values for the PVRQOL were: mean±SD; 92.60±10.82. PVHI showed significant improvement after surgery: mean±SD; 2.93±6.98 (P<0.001). Postoperative PVRQOL had a significant improvement: mean±SD; 98.11±5.82 (P<0.001).

CONCLUSION

Adenotonsillectomy improved PVHI and PVRQOL scores in children with adenotonsillar problems, regardless of obstructive or infectious surgical indications.

Hypertrophic cardiomyopathy associated with sleep apnea: serious implications and cogent management strategy

Obstructive sleep apnea (OSA) affects an estimated 20 million adult Americans and is present in a large proportion of patients with hypertension and in those with other cardiovascular disorders, including hypertrophic cardiomyopathy (HCM). This review seeks to highlight concepts and evidence important to understanding the interactions between OSA and HCM, with particular attention to more recent advances in patient-oriented research. Studies of patients with HCM have found the prevalence of sleep-disordered breathing to range from 40 to 80%. Increased sympathetic activity, impaired vagal activity, increased afterload, insulin resistance and endothelial dysfunction have been proposed as potential mechanisms for the association. Specific questions include whether OSA is important in unmasking symptoms in hitherto undiagnosed patients with HCM, whether OSA in patients with established HCM accelerates disease progression and whether treatment of OSA results in clinical improvement, fewer cardiovascular events and reduced mortality. Because obesity, cardiovascular disease, metabolic syndrome, and diabetes are often present in patients with OSA, it can be difficult to attribute abnormalities evident in the sleep apnea patient with HCM to the effects of OSA, the effects of HCM or synergies between these conditions. Although further research is needed to answer these specific questions, recent investigations have clearly shown the coexistence of OSA and HCM, as well as elucidated the contribution of heightened sympathetic nerve activity in OSA to drug-refractory symptoms and worsening left ventricular outflow tract obstruction. This review aims to highlight the current literature available on the association of OSA and HCM, provide directions for future research and summarize the key features related to this association based on the authors' best understanding and experience.

A 2-year mean follow-up of oral appliance therapy for severe obstructive sleep apnea: a cohort study

OBJECTIVE

Oral appliances for treating severe obstructive sleep apnea (OSA) are recommended for patients who failed to comply with continuous positive airway pressure (CPAP) treatment. The objective of this study was to evaluate medium long-term outcome and success rates of oral appliances in patients with severe OSA.

METHODS

In a retrospective study, 52 OSA patients with an apnea-hypopnea index (AHI) ≥40, who did not tolerate CPAP treatment, were enrolled and fitted with a modified Herbst oral appliance. A 2-year mean follow-up including a second somnography was conducted in 36 of the patients.

RESULTS

A significant reduction (P < 0.0001) in the AHI was demonstrated between the initial somnography (55.25 ± 10.79,) and the followed one (17.74 ± 11.0, n = 36). Overall, 57.7% of total study subjects (n = 52) and 63.9% (n = 36) that had sequential sonmogarphy continued using the device. The reduction in AHI in the user group was 42.4 ± 3.1 (n = 23), which was significantly higher (P = 0.013) than in the non-user group (28.9 ± 17.2; n = 13). Moreover, 53% (n = 19) reached AHI of <15.

CONCLUSIONS

Oral appliances were found to be successful for treating for severe OSA after first-line treatment had failed.

Relationship between obstructive sleep apnea and markers of cardiovascular alterations in never-treated hypertensive patients

We addressed a question if there is a relationship between severity of newly diagnosed obstructive sleep apnea (OSA) and markers of cardiovascular alterations in middle-aged untreated hypertensive patients. In 121 consecutive patients with never-treated essential hypertension (mean age 35.9±10.1 years; 97 men and 24 women) evaluation of office and ambulatory blood pressure (BP) measurements, metabolic syndrome (MS) components and markers of alterations in cardiovascular system including left ventricular structure and function, carotid artery wall intima-media thickness (cIMT) and urinary albumin excretion (UAE) was performed. OSA was classified as mild (apnea/hypopnea index (AHI) 5-15 events h(-1)) or moderate-to-severe (AHI >15 events h(-1)). Mild and moderate-to-severe OSA were diagnosed in 30% and 20% of patients, respectively. No differences in nighttime BP levels and decline between patients with and without OSA were observed. The patients with moderate-to-severe OSA were characterized by higher cIMT (0.74±0.16 vs. 0.60±0.15 mm; P=0.001), UAE (14.5±6.9 vs. 10.0±8.0 mg 24 h(-1); P=0.014), relative wall thickness (0.42±0.05 vs. 0.39±0.05; P=0.023) and by a higher degree of diastolic dysfunction (E'-wave velocity 11.4±3.2 vs. 15.5±3.8 m s(-1); P<0.001) as compared with the patients without OSA. In multivariate analysis, AHI independently of BP and MS components correlated with UAE, relative wall thickness and E'-wave velocity. In the middle-aged never-treated hypertensive patients, moderate-to-severe OSA correlates with markers of cardiovascular alterations independently of BP levels and MS components.

Sleep related quality of life before and after adenotonsillar surgery in pediatric population

OBJECTIVE

To assess the quality of life in children with adenotonsillar problems before and after adenotonsillectomy in short term follow-up.

METHODS

Quasi-experimental study (before and after study) of children with adenotonsillar problems at Tehran University of Medical Sciences, Amir'Alam hospital. Eighty six pediatric patients aged 3 through 13 years (58 boys and 28 girls) who underwent adenotonsillectomy, for treatment of sleep disordered breathing or recurrent throat infection, were recruited. Parents completed OSA-18 quality of life survey and Brouillette score questionnaire before and one month after surgery.

RESULTS

Reliability of the Brouillette score and OSA-18 survey was established by evaluating the Cronbach α value. Cronbach α for Brouillette score was 0.70 and for OSA-18 survey it was 0.88. Preoperative values for the OSA-18 total and domain scores were high in children: mean±SD; 61.65±20.78. Preoperative values for the Brouillette score were: mean±SD; 0.41±2.34. The total OSA-18 survey score and the scores for all domains showed significant improvement after surgery: mean±SD; 28.01±9.09 (P<0.001). Post-operative Brouillette score had a significant improvement: mean±SD; -3.57±0.91 (P<0.001).

CONCLUSION

Considering the OSA-18 survey and Brouillete score results, surgical therapy with adenotonsillectomy is associated with marked improvement in quality of life in both obstructive and infective adenotonsillar disease.

Obstructive sleep apnoea and cardiovascular complications: perception versus knowledge

Epidemiological evidence has confirmed that obstructive sleep apnoea (OSA) significantly promotes cardiovascular risk, independent of age, sex, race and other common risk factors for cardiovascular diseases, such as smoking, drinking, obesity, diabetes mellitus, dyslipidaemia and hypertension. Patients with severe OSA exhibit a higher prevalence of coronary artery disease, heart failure and stroke. Despite the tight correlation between sleep apnoea and these comorbidities, the mechanisms behind increased cardiovascular risk in OSA remain elusive. Several theories have been postulated, including sympathetic activation, endothelial dysfunction, oxidative stress and inflammation. The association between OSA and cardiovascular diseases may be rather complicated and compounded by the presence of components of metabolic syndrome, such as obesity, hypertension, diabetes mellitus and dyslipidaemia. The present minireview updates current knowledge with regard to the cardiovascular sequelae of OSA and the mechanisms involved.

Secondary arterial hypertension: when, who, and how to screen?

Secondary hypertension refers to arterial hypertension due to an identifiable cause and affects ∼5-10% of the general hypertensive population. Because secondary forms are rare and work up is time-consuming and expensive, only patients with clinical suspicion should be screened. In recent years, some new aspects gained importance regarding this screening. In particular, increasing evidence suggests that 24 h ambulatory blood pressure (BP) monitoring plays a central role in the work up of patients with suspected secondary hypertension. Moreover, obstructive sleep apnoea has been identified as one of the most frequent causes. Finally, the introduction of catheter-based renal denervation for the treatment of patients with resistant hypertension has dramatically increased the interest and the number of patients evaluated for renal artery stenosis. We review the clinical clues of the most common causes of secondary hypertension. Specific recommendations are given as to evaluation and treatment of various forms of secondary hypertension. Despite appropriate therapy or even removal of the secondary cause, BP rarely ever returns to normal with long-term follow-up. Such residue hypertension indicates either that some patients with secondary hypertension also have concomitant essential hypertension or that irreversible vascular remodelling has taken place. Thus, in patients with potentially reversible causes of hypertension, early detection and treatment are important to minimize/prevent irreversible changes in the vasculature and target organs.

Obstructive sleep apnea severity is associated with left ventricular mass independent of other cardiovascular risk factors in morbid obesity

OBJECTIVE

To evaluate the relation between obstructive sleep apnea (OSA) and left ventricular mass (LVM) in morbid obesity and the influence of gender, menopausal status, anthropometry, body composition, hypertension, and other cardiovascular risk factors in this relationship.

DESIGN

Cross-sectional descriptive study.

METHODS

Polysomnographic and echocardiographic studies were performed in a cohort of 242 patients (86 men, 100 premenopausal (PreM) and 56 postmenopausal (PostM) women), with grade II obesity and above (BMI: 43.7 ± 0.4 kg/m(2)) to investigate OSA and LVM respectively. Anthropometry, body composition, glucose tolerance, and blood pressure were also recorded.

RESULTS

OSA to different degrees was diagnosed in 76.2% of the patients (n: 166), its prevalence being 90.9% (n: 70) for men, and 76% (n: 38) and 63.8% (n: 58) for PostM and PreM women, respectively (p < 0.01). LVM excess was greatest for PostM women (90.2%), followed by men (81.9%) and PreM females (69.6%) (p < 0.01). LVM values increased in accordance to OSA severity (absence, 193.7 ± 6.9 g; mild, 192.6 ± 7.8 g; moderate, 240.5 ± 12.5 g; severe, 273.6 ± 14.6 g; p < 0.01). LVM magnitude correlated with the menopausal state, age, central adiposity, hypertension (HT), type 2 diabetes (DM), desaturation index (DI), and apnea-hypopnea index (AHI) (r = 0.41; p < 0.01). The relationship between LVM and AHI persisted in the multivariate analysis (β = 0.25; p < 0.05) after adjusting for age, gender, menopausal state, BMI, waist circumference, neck circumference, DI, fasting plasma glucose, DM, and HT. But if tobacco habits are included, the statistical difference disappears (β = 0.22; p = 0.06).

CONCLUSIONS

Morbid obesity is frequently associated with abnormal LVM, particularly in patients with OSA; this association is independent of HT, BMI, body composition, and other clinical factors, supporting a direct role of OSA on LVM in morbid obesity. This suggests that OSA and LVM might be taken as predictors of the cardiovascular risk in these patients.

Intima-media thickness in patients with obstructive sleep apnea without comorbidities

Background

Obstructive sleep apnea (OSA) is associated with elevated risk of cardiovascular events. The early stages of vascular complications can be visualized by means of ultrasound. Intima-media thickness (IMT) correlates with the presence of risk factors of cardiovascular diseases such as hypertension, diabetes, tobacco smoking, or hyperlipidemia. However, little is known whether OSA itself may be the cause of IMT thickening.

Methods

The study group was composed of 28 patients (6 women, 22 men; mean age = 53.8 years, mean BMI = 27.1 kg/m², mean AHI = 22.4/h) with OSA who had no comorbidities. The control group consisted of 28 healthy subjects (6 women, 22 men; mean age = 53.9 years; mean BMI = 27.5 kg/m²). In both groups IMT was assessed in common carotid arteries with the use of ultrasonography. Additionally, in patients with OSA, pulse wave velocity, echocardiography, 24-h automated blood pressure monitoring, clinical signs and symptoms, and blood tests were performed to investigate possible correlations with IMT.

Results

Median IMT was 0.41 mm in OSA patients and 0.46 mm in the control group (p = 0.087). Echocardiography revealed left ventricle hypertrophy in 21 %, systolic disorders in 8 %, and diastolic disorders in 57 % of the patients. In a large majority of patients, pulse wave velocity was found to be normal. IMT correlated with age (r = 0.446, p = 0.017), total cholesterol (r = 0.518, p = 0.005), daytime systolic blood pressure (r = 0.422, p = 0.025), pulse pressure 24 h and daytime (r = 0.424, p = 0.027 and r = 0.449, p = 0.019), early mitral flow/atrial mitral flow (E/A) (r = −0.429, p = 0.023), and posterior wall diameter (PWD) (r = 0.417, p = 0.270).

Conclusion

In a relatively nonobese group of patients, no significant differences were found in the intima-media thickness between OSA patients without concomitant cardiovascular diseases and healthy controls. This may lead to the conclusion that IMT does not reflect increased risk of cardiovascular events in patients with isolated OSA.

Periodic limb movements in sleep contribute to further cardiac structure abnormalities in hemodialysis patients with restless legs syndrome

STUDY OBJECTIVES

In hemodialysis (HD) patients, restless legs syndrome (RLS) and periodic limb movements in sleep (PLMS) constitute common sleep disorders. Recent findings indicate a role for PLMS as a risk factor in the development of new or the aggravation of existing cardiovascular disease. The aim of the current study was to investigate the association of PLMS with indices of cardiac morphology and function in HD patients with RLS as a potential pathway by which PLMS could alter cardiovascular risk.

METHODS

Based on PLMS diagnosis by an overnight polysomnographic evaluation, 19 stable HD-RLS patients were divided into the PLMS group (n = 10) and the non-PLMS group (n = 9). During the overnight assessment, nocturnal blood pressure (BP) indices were also assessed. Left ventricular (LV) dimensions were examined by M-mode echocardiography, whereas LV diastolic function was evaluated by conventional Doppler and tissue Doppler imaging the following day.

RESULTS

LV internal diameter in diastole was significantly increased in the PLMS group (4.96 ± 0.61 vs 4.19 ± 0.48 cm, p = 0.007), leading to a significantly increase in LV mass (202 ± 52 vs 150 ± 37 g, p = 0.026). In contrast, no between group differences were observed in diastolic function indices (p > 0.05).

CONCLUSIONS

These are the first data to associate severe PLMS with further LV structure abnormalities in HD patients with RLS.