Obstructive sleep apnea is associated with nonsustained ventricular tachycardia in patients with hypertrophic obstructive cardiomyopathy

Machine learning-based detection of sleep-disordered breathing in hypertrophic cardiomyopathy

BACKGROUND

Hypertrophic cardiomyopathy (HCM) is often concomitant with sleep-disordered breathing (SDB), which can cause adverse cardiovascular events. Although an appropriate approach to SDB prevents cardiac remodelling, detection of concomitant SDB in patients with HCM remains suboptimal. Thus, we aimed to develop a machine learning-based discriminant model for SDB in HCM.

METHODS

In the present multicentre study, we consecutively registered patients with HCM and performed nocturnal oximetry. The outcome was a high Oxygen Desaturation Index (ODI), defined as 3% ODI >10, which significantly correlated with the presence of moderate or severe SDB. We randomly divided the whole participants into a training set (80%) and a test set (20%). With data from the training set, we developed a random forest discriminant model for high ODI based on clinical parameters. We tested the ability of the discriminant model on the test set and compared it with a previous logistic regression model for distinguishing SDB in patients with HCM.

RESULTS

Among 369 patients with HCM, 228 (61.8%) had high ODI. In the test set, the area under the receiver operating characteristic curve of the discriminant model was 0.86 (95% CI 0.77 to 0.94). The sensitivity was 0.91 (95% CI 0.79 to 0.98) and specificity was 0.68 (95% CI 0.48 to 0.84). When the test set was divided into low-probability and high-probability groups, the high-probability group had a higher prevalence of high ODI than the low-probability group (82.4% vs 17.4%, OR 20.9 (95% CI 5.3 to 105.8), Fisher's exact test p<0.001). The discriminant model significantly outperformed the previous logistic regression model (DeLong test p=0.03).

CONCLUSIONS

Our study serves as the first to develop a machine learning-based discriminant model for the concomitance of SDB in patients with HCM. The discriminant model may facilitate cost-effective screening tests and treatments for SDB in the population with HCM.

2024 AHA/ACC/AMSSM/HRS/PACES/SCMR Guideline for the Management of Hypertrophic Cardiomyopathy: A Report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines

AIM

The "2024 AHA/ACC/AMSSM/HRS/PACES/SCMR Guideline for the Management of Hypertrophic Cardiomyopathy" provides recommendations to guide clinicians in the management of patients with hypertrophic cardiomyopathy.

METHODS

A comprehensive literature search was conducted from September 14, 2022, to November 22, 2022, encompassing studies, reviews, and other evidence on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, the Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline. Additional relevant studies, published through May 23, 2023, during the guideline writing process, were also considered by the writing committee and added to the evidence tables, where appropriate.

STRUCTURE

Hypertrophic cardiomyopathy remains a common genetic heart disease reported in populations globally. Recommendations from the "2020 AHA/ACC Guideline for the Diagnosis and Treatment of Patients With Hypertrophic Cardiomyopathy" have been updated with new evidence to guide clinicians.

2024 AHA/ACC/AMSSM/HRS/PACES/SCMR Guideline for the Management of Hypertrophic Cardiomyopathy: A Report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines

AIM

The "2024 AHA/ACC/AMSSM/HRS/PACES/SCMR Guideline for the Management of Hypertrophic Cardiomyopathy" provides recommendations to guide clinicians in the management of patients with hypertrophic cardiomyopathy.

METHODS

A comprehensive literature search was conducted from September 14, 2022, to November 22, 2022, encompassing studies, reviews, and other evidence on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, the Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline. Additional relevant studies, published through May 23, 2023, during the guideline writing process, were also considered by the writing committee and added to the evidence tables, where appropriate.

STRUCTURE

Hypertrophic cardiomyopathy remains a common genetic heart disease reported in populations globally. Recommendations from the "2020 AHA/ACC Guideline for the Diagnosis and Treatment of Patients With Hypertrophic Cardiomyopathy" have been updated with new evidence to guide clinicians.

Cardiac autonomic dysfunction and structural remodeling: the potential mechanism to mediate the relationship between obstructive sleep apnea and cardiac arrhythmias

Background

Cardiac arrhythmias are very common in patients with obstructive sleep apnea (OSA), especially atrial fibrillation (AF) and nonsustained ventricular tachycardia (NVST). Cardiac autonomic dysfunction and structural remodeling caused by OSA provide the milieu for cardiac arrhythmia development. This study aimed to determine whether OSA is associated with various cardiac arrhythmias and investigate potential pathophysiologic pathways between them.

Methods

The analysis covered 600 patients with clinical suspicion of OSA hospitalized in Renmin Hospital of Wuhan University between January 2020 and May 2023. After undergoing sleep apnea monitor, all subjects received laboratory tests, Holter electrocardiography, and Echocardiography.

Results

Compared with those without OSA and adjusting for potential confounders, subjects with moderate OSA had three times the odds of AF (odds ratio [OR] 3.055; 95% confidence interval [CI], 1.002-9.316; p = 0.048). Subjects with severe OSA had three times the odds of AF (OR 3.881; 95% CI, 1.306-11.534; p = 0.015) and NSVT (OR 3.690; 95% CI, 0.809-16.036; p = 0.046). There were significant linear trends for the association between OSA severity with AF and NVST (p < 0.05). And this association was mediated by cardiac structural changes including left atrial diameter, left ventricular diastolic diameter, right atrial diameter and right ventricular diameter. In addition, the ratio of low-frequency and high-frequency individually mediated the association between severe OSA and NVST.

Conclusion

This study demonstrated that severe OSA was independently associated with AF and NSVT, and this association was mediated by autonomic nervous system changes and cardiac structural remodeling.

Ventricular Tachycardia in Patients With Pre-eclampsia: Prevalence, Predictors, and Associated In-Hospital Adverse Events

Introduction Pre-eclampsia is a pregnancy-associated multisystem disorder; in rare cases, it can be complicated by arrhythmias such as ventricular tachycardia (VT). The purpose of this study was to determine the prevalence and predictors of VT among patients admitted with pre-eclampsia as well as to analyze the independent association of VT with in-hospital outcomes in this population. Methods Data were obtained from the National Inpatient Sample from January 2016 to December 2019. Patients with a primary diagnosis of pre-eclampsia were selected using International Classification of Diseases, 10th Revision, Clinical Modification (ICD-10-CM) codes. Subsequently, the study population was divided into patients who developed VT versus patients who did not develop this complication. We then assessed the predictors of VT in women with pre-eclampsia as well as the independent association of VT with outcomes taking into account confounders such as age, race, and comorbidities. Results Of 255,946 patients with pre-eclampsia, 92 developed VT (0.04%) during their hospital stay. Multivariate logistic regression showed that patients with VT were far more likely to develop cardiac arrest (adjusted odds ratio, or aOR: 92.582, 95% CI: 30.958-276.871, p=0.001), require permanent pacemaker implantation (aOR: 41.866, 95% CI: 14.800-118.432, p=0.001), develop postpartum hemorrhage (aOR: 2.932, 95% CI: 1.655-5.196, p=0.001), and require left heart catheterization (aOR: 19.508, 95% CI: 3.261-116.708, p=0.001). Predictors of VT included being African American (aOR: 1.939, 95% CI: 1.183-3.177, p=0.009), cerebrovascular disease (aOR: 23.109, 95% CI: 6.953-76.802, p=0.001), congestive heart failure (aOR: 50.340, 95% CI: 28.829-87.901, p=0.001), atrial fibrillation (aOR: 20.148, 95% CI: 6.179-65.690, p=0.001), and obstructive sleep apnea, or OSA (aOR: 3.951, 95% CI: 1.486-10.505, p=0.006). Patients in the VT cohort were found to have an increased length of hospital stay compared to the non-VT cohort (7.16 vs. 4.13 days, p=0.001). Conclusion In a large cohort of women admitted with pre-eclampsia, we found the prevalence of VT to be <1%. Predictors of VT included conditions such as atrial fibrillation, congestive heart failure, and OSA and being African American. VT was found to be independently associated with several adverse outcomes as well as an increased length of hospital stay.

Effect of type 2 diabetes on cardiac arrhythmias in patients with obstructive hypertrophic cardiomyopathy

AIMS

Type 2 diabetes (T2D), a prevalent cardiovascular disease, is linked with cardiac arrhythmias such as atrial fibrillation (AF) and ventricular arrhythmia. This study evaluated T2D's impact on these arrhythmias in patients with obstructive hypertrophic cardiomyopathy (OHCM).

METHODS AND MATERIALS

We retrospectively analyzed the data of 75 patients with OHCM and T2D from two medical centers in China from 2011 to 2020. A propensity score-matched cohort of 150 patients without T2D was also analyzed.

RESULTS

Altogether, 225 patients were included. The prevalence of supraventricular tachycardia (SVT), AF, and non-sustained ventricular tachycardia (NSVT) was higher in patients with HCM and T2D than in those without T2D. Multivariate logistic regression showed T2D as an independent risk factor for SVT (odds ratio [OR] = 1.90, 95% confidence interval [CI] = 1.01-3.58, P = 0.04), AF (OR = 2.68, 95% CI = 1.27-5.67, P = 0.01), and NSVT (OR = 2.18, 95% CI = 1.04-4.57, P = 0.04). Further analysis identified fasting glucose and glycosylated hemoglobin levels as independent risk factors for AF and NSVT in patients with T2D.

CONCLUSIONS

T2D independently increases the risk of cardiac arrhythmias (SVT, AF, NSVT) in OHCM patients. Furthermore, fasting glucose and glycosylated hemoglobin levels independently heighten AF and NSVT risk in OHCM patients with T2D.

Ventricular Arrhythmias in Patients with Implanted Cardiac Devices at High Risk of Obstructive Sleep Apnea

Background and Objectives: Patients with pre-existing cardiac disease have a higher prevalence of Obstructive Sleep Apnea (OSA). OSA has been associated with an increased risk of supraventricular and ventricular arrhythmia. We screened subjects with implanted pacemakers and automated implantable cardioverter defibrillators (AICD) for OSA with the Berlin Questionnaire and compared the incidence of ventricular arrhythmias and automated implantable cardioverter defibrillator (AICD) firing between high and low OSA risk groups. Materials and Methods: We contacted 648 consecutive patients from our arrhythmia clinic to participate in the study and performed final analyses on 171 subjects who consented and had follow-up data. Data were abstracted from the electronic health record for the incidence of non-sustained ventricular tachycardia (NSVT), ventricular tachycardia (VT), ventricular fibrillation (VF) and AICD firing and then compared between those at high versus low risk of OSA using the Berlin Questionnaire and multivariate negative binomial regression. Results: The average follow-up period was 24.2 ± 4.4 months. After adjusting for age, gender and history of heart failure, those subjects at high risk of OSA had a higher burden of NSVT vs. those with a low risk of OSA (33.4 ± 96.2 vs. 5.82 ± 17.1 episodes, p = 0.003). A predetermined subgroup analysis of AICD recipients also demonstrated a significantly higher burden of NSVT in the high vs. low OSA risk groups (66.2 ± 128.6 vs. 18.9 ± 36.7 episodes, p = 0.033). There were significant differences in the rates of VT, VF or AICD shock burden between the high and low OSA risk groups and in the AICD subgroup analysis. Conclusions: There was increased ventricular ectopy among pacemaker and AICD recipients at high risk of OSA, but the prevalence of VT, VF or AICD shocks was similar to those with low risk of OSA.

Relation of Mitral Leaflet Elongation to Nonsustained Ventricular Tachycardia in Patients with Obstructive Hypertrophic Cardiomyopathy

The impact of mitral valve abnormality on the occurrence of non-sustained ventricular tachycardia (NSVT) in patients with hypertrophic cardiomyopathy (HC) has not been well determined. We sought to demonstrate the relation of mitral valve abnormalities with NSVT in patients with obstructive HC. Three hundred and sixteen adult patients with obstructive HC with at least 1 Holter electrocardiographic monitoring and cardiac magnetic resonance (CMR) from 2014 to 2018 were enrolled. CMR images and Holter electrocardiography were analyzed in all patients. NSVT occurred in 50 patients (16%). Compared with those without NSVT, anterior mitral leaflet and posterior mitral leaflet lengths was significantly increased in patients with NSVT (AML 32.0 ± 5.0mm vs. 26.1±4.8mm, p<0.001; PML 17.7±3.7mm vs. 15.2±2.7mm, p<0.001, respectively). Multivariate logistic regression analysis indicated that elongated AML and PML were significantly independent predictors of NSVT (AML: OR 1.261, 95%CI 1.156-1.375, p<0.001; PML: OR 1.126, 95%CI 1.001-1.265, p=0.047). Furthermore, the area under the receiver operating characteristic curve for AML was 0.812. At a cutoff valve of 27.5mm, AML length had a sensitivity of 86% and specificity of 65%. Elongated mitral leaflets independently correlated with NSVT in patients with obstructive HC. Furthermore, the morphological abnormalities of mitral valve could serve as a useful marker for improving risk stratification of SCD and may play a role in optimizing surgical strategy for patients with obstructive HC.

Sex Differences in Hypertrophic Cardiomyopathy: Interaction With Genetics and Environment

Purpose of Review

We explore the sex-specific interaction of genetics and the environment on the clinical course and outcomes of hypertrophic cardiomyopathy (HCM).

Recent Findings

Women account for approximately one-third of patients in specialist HCM centres and reported in observational studies. As a result, evidence informing clinical guideline recommendations is based predominantly on risk factors and outcomes seen in men. However, disease progression appears to be different between the sexes. Women present at a more advanced stage of disease, are older at diagnosis, have higher symptom burden, carry greater risk for heart failure and are at greater risk of mortality compared to men. Women are more likely to be gene-positive, while men are more likely to be gene-negative. The risk of sudden cardiac death and access to specialised care do not differ between the sexes.

Summary

Reporting sex-disaggregated results is essential to identify the mechanisms leading to sex differences in HCM.

Risk Factors of Pulmonary Arterial Hypertension and Its Relationship With Atrial Fibrillation in Patients With Obstructive Hypertrophic Cardiomyopathy

Background: Pulmonary arterial hypertension (PH) is a common complication in patients with obstructive hypertrophic cardiomyopathy (OHCM). The risk factor of PH in patients with OHCM has not been fully elucidated, and even atrial fibrillation (AF) was considered a risk factor of PH. Thus, our study aimed to investigate risk factors of PH and the relationship between PH and AF in patients with OHCM.

Methods: We retrospectively enrolled 483 consecutive patients diagnosed with OHCM at Fuwai Hospital (Beijing, China) from January 2015 to December 2017. Clinical and echocardiographic parameters were compared between patients with and without PH.

Results: Eighty-two (17.0%) patients were diagnosed with PH in this study. Compared to patients without PH, those with PH were significantly older, had a lower body mass index (BMI), were more likely to be female and more symptomatic [New York Heart Association Class 3 or 4 symptoms], and had a higher AF prevalence. A multivariate analysis indicated that AF was an independent risk factor of PH (odds ratio [OR] 2.31, 95% confidence interval [CI] 1.03–5.20, p = 0.042). Moreover, PH was independently associated with a higher AF incidence after adjusting for age and left atrial diameter (OR 2.24, 95% CI 1.07–4.72, p = 0.034).

Conclusion: AF was independently associated with PH in patients with OHCM. Further, PH was significantly associated with an increased risk of AF, which suggested that AF could aggravate PH and that PH may promote AF processes, forming a vicious circle.

Clinical predictors of the presence of obstructive sleep apnea in patients with hypertrophic cardiomyopathy

Obstructive sleep apnea (OSA) is much common and associated with worse clinical outcomes in patients with hypertrophic cardiomyopathy (HCM), however, the diagnosis of OSA in HCM is still insufficient. We aim to investigate the clinical predictors of OSA in a large series of patients with HCM. A total of 589 patients with HCM who underwent sleep evaluations were retrospectively enrolled. Data from clinical characteristics and polysomnography studies were recorded. OSA was present in 346 patients (58.7%). Patients who had OSA were older, more likely to be male and had more clinical comorbidities such as hypertension, atrial fibrillation and cardiac remodeling. Multivariate logistic analyses showed that male, age, body mass index, hypertension and left ventricular outflow tract obstruction were significant factors associated with OSA. The area under the ROC curve (AUC) was 0.78 (95% CI 0.74-0.82; P < 0.001). These factors were also able to identify moderate to severe OSA with an AUC of 0.77 (95% CI 0.73-0.81; P < 0.001). These findings suggest that identifying HCM patients with high risk for OSA is feasible using characteristics from clinical practices and clinicians should have no hesitate to conduct sleep test in these patients.

Mid-ventricular obstruction is associated with non-sustained ventricular tachycardia in patients with hypertrophic obstructive cardiomyopathy

Background

Mid‐ventricular obstruction (MVO) is a rare subtype of hypertrophic cardiomyopathy (HCM) but it is associated with ventricular arrhythmia. The relationship between MVO and non‐sustained ventricular tachycardia (NSVT) in HCM patients is unknown.

Hypothesis

The severity of MVO increases the incidence of NSVT in patients with hypertrophic obstructive cardiomyopathy (HOCM).

Methods

Five hundred and seventy‐two consecutive patients diagnosed with HOCM in Fuwai Hospital between January 2015 and December 2017 were enrolled in this study. Holter electrocardiographic and clinical parameters were compared between HOCM patients with and without MVO.

Results

Seventy‐six (13.3%) of 572 patients were diagnosed with MVO. Compared to patients without MVO, those with MVO were much younger, and had a higher incidence of syncope, greater left ventricular (LV) posterior wall thickness, a higher percentage of LV late gadolinium enhancement, and higher prevalence of NSVT. Furthermore, the prevalence of NSVT increased with the severity of MVO (without, mild, moderate or severe: 11.1%, 18.2%, 25.6%, respectively, p for trend < .01). Similarly, the prevalence of NSVT differed among patients with isolated LV outflow tract (LVOTO), both MVO and LVOTO, and isolated MVO (11.1%, 21.3%, 26.6%, respectively, p for trend = .018). In addition to age, diabetes, left atrial diameter, and maximal wall thickness, multivariate analysis revealed the presence of MVO as an independent risk factor for NSVT (Odds ratio 2.69; 95% confidence interval 1.41 to 5.13, p = .003).

Conclusions

The presence and severity of MVO was associated with higher incidence of NSVT in HOCM patients.

Combined Effect of Mediterranean Diet and Aerobic Exercise on Weight Loss and Clinical Status in Obese Symptomatic Patients with Hypertrophic Cardiomyopathy

We evaluated the impact of weight loss (WL) using a Mediterranean diet and mild-to-moderate-intensity aerobic exercise program, on clinical status of obese, symptomatic patients with hypertrophic cardiomyopathy (HCM). Compared with nonresponders, responders showed a significant reduction of left atrial diameter, left atrial volume index (LAVI), E/E'average, pulmonary artery systolic pressure (PASP), and a significant increase in Vo_2max (%) and peak workload. Body mass index changes correlated with reduction in left atrial diameter, LAVI, E/E'average, PASP, and increase of Vo_2max (mL/Kg/min), Vo_2max (%), peak workload. Mediterranean diet and aerobic exercise is associated with clinical-hemodynamic improvement in obese symptomatic HCM patients.

Relationship Between Obstructive Sleep Apnea and Late Gadolinium Enhancement and Their Effect on Cardiac Arrhythmias in Patients with Hypertrophic Obstructive Cardiomyopathy

PURPOSE

Obstructive sleep apnea (OSA) and myocardial fibrosis are associated with cardiac arrhythmia. The purpose of this study was to explore the relationship between OSA and myocardial fibrosis, as well as their impact on cardiac arrhythmia in hypertrophic obstructive cardiomyopathy (HOCM) patients.

METHODS

We prospectively studied 151 consecutive patients with a confirmed diagnosis of HOCM at the Fuwai Hospital between September 2017 and 2018. Polysomnography, Holter electrocardiography, and cardiac magnetic resonance imaging were performed on all patients. Myocardial fibrosis was reflected by late gadolinium enhancement (LGE), detected using cardiac magnetic resonance imaging.

RESULTS

Myocardial fibrosis, measured using LGE%, was found to increase with increasing OSA severity [6.8% (3.6-12.9%), 6.1% (3.4-10.0%), 9.6% (5.5-14.5%), and 15.5% (9.3-20.0%) for no-OSA, mild OSA, moderate OSA, and severe OSA, respectively; p=0.003]. LGE% correlated with the New York Heart Association functional classifications (p=0.018), septal thickness (p=0.026), and apnea-hypopnea index (AHI) (p<0.001). The prevalence of isolated premature ventricular contraction (PVC) (p=0.028), paired PVC (p=0.036), ventricular bigeminy (p=0.005)/trigeminy (p<0.001), non-sustained ventricular tachycardia (NSVT) (p=0.001), isolated premature atrial contraction (PAC) (p=0.032), and supraventricular tachycardia (p=0.029) was significantly higher in patients with OSA. Additionally, LGE% and AHI were independent risk factors for isolated PVC (OR: 1.04, p=0.001 and OR: 1.07, p=0.039, respectively), ventricular bigeminy (OR: 1.04, p=0.003 and OR: 1.26, p=0.002, respectively)/trigeminy (OR: 1.07, p=0.040 and OR: 1.06, p=0.001, respectively), and NSVT (OR: 1.17, p<0.001 and OR: 1.08, p<0.001, respectively) after adjustment for age, sex, and other parameters.

CONCLUSION

Both OSA and LGE% were associated with a greater likelihood and increased frequency of ventricular arrhythmias (including NSVT) in patients with HOCM. Thus, the severity of OSA was independently associated with more severe myocardial fibrosis in patients with HOCM.

2020 AHA/ACC Guideline for the Diagnosis and Treatment of Patients With Hypertrophic Cardiomyopathy: Executive Summary: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

This executive summary of the hypertrophic cardiomyopathy clinical practice guideline provides recommendations and algorithms for clinicians to diagnose and manage hypertrophic cardiomyopathy in adult and pediatric patients as well as supporting documentation to encourage their use.

METHODS

A comprehensive literature search was conducted from January 1, 2010, to April 30, 2020, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Collaboration, Agency for Healthcare Research and Quality reports, and other relevant databases.

STRUCTURE

Many recommendations from the earlier hypertrophic cardiomyopathy guidelines have been updated with new evidence or a better understanding of earlier evidence. This summary operationalizes the recommendations from the full guideline and presents a combination of diagnostic work-up, genetic and family screening, risk stratification approaches, lifestyle modifications, surgical and catheter interventions, and medications that constitute components of guideline directed medical therapy. For both guideline-directed medical therapy and other recommended drug treatment regimens, the reader is advised to follow dosing, contraindications and drug-drug interactions based on product insert materials.

2020 AHA/ACC Guideline for the Diagnosis and Treatment of Patients With Hypertrophic Cardiomyopathy: Executive Summary: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

Aim This executive summary of the hypertrophic cardiomyopathy clinical practice guideline provides recommendations and algorithms for clinicians to diagnose and manage hypertrophic cardiomyopathy in adult and pediatric patients as well as supporting documentation to encourage their use. Methods A comprehensive literature search was conducted from January 1, 2010, to April 30, 2020, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Collaboration, Agency for Healthcare Research and Quality reports, and other relevant databases. Structure Many recommendations from the earlier hypertrophic cardiomyopathy guidelines have been updated with new evidence or a better understanding of earlier evidence. This summary operationalizes the recommendations from the full guideline and presents a combination of diagnostic work-up, genetic and family screening, risk stratification approaches, lifestyle modifications, surgical and catheter interventions, and medications that constitute components of guideline directed medical therapy. For both guideline-directed medical therapy and other recommended drug treatment regimens, the reader is advised to follow dosing, contraindications and drug-drug interactions based on product insert materials.

Effect of obstructive sleep apnea on right ventricular ejection fraction in patients with hypertrophic obstructive cardiomyopathy

Background

Obstructive sleep apnea (OSA) is a common disease associated with worse structural and functional impairment of the heart in patients with hypertrophic obstructive cardiomyopathy (HOCM).

Hypothesis

The presence and severity of OSA can decrease the right ventricular ejection fraction (RVEF) in patients with HOCM.

Methods

In total, 151 consecutive patients with a confirmed diagnosis of HOCM at Fuwai Hospital between September 2017 and September 2018 were included. Polysomnography and cardiac magnetic resonance imaging were performed in all patients.

Results

Overall, 84 (55.6%) patients were diagnosed with OSA. The RVEF significantly decreased with the severity of OSA (none, mild, moderate‐severe: 46.1 ± 8.2 vs 42.9 ± 7.5 vs 41.4 ± 7.4, P = .009). The apnea‐hypopnea index (AHI) was significantly high in patients with RVEF<40% among the different OSA groups (mild, moderate:7.7 ± 2.4 vs 9.6 ± 2.9, P = .03; 24.4 ± 9.0 vs 36.3 ± 18.0, P = .01). In the multiple linear regression model, the right ventricular end‐systolic volume (β = −0.28, P < .001), AHI (β = −0.09, P = .02), and oxygen desaturation index (β = −0.11, P = .04) were independently associated with a decrease in RVEF (adjusted R² = 0.347, P < .001). Furthermore, the prevalence of RVEF<40% was high in patients with OSA. Compared with RVEF>40%, RVEF<40% was associated with more symptoms, mainly chest pain, chest distress, NYHA class III or IV, pulmonary hypertension, and moderate or severe mitral regurgitation.

Conclusion

In patients with HOCM, the presence and severity of OSA is independently associated with a lower RVEF. In addition, compared with patients with RVEF>40%, those with RVEF<40% had more symptoms, including chest pain, chest distress, and NYHA class III or IV.

Association between severity of obstructive sleep apnea and high-sensitivity C-reactive protein in patients with hypertrophic obstructive cardiomyopathy

Background

Obstructive sleep apnea (OSA) is highly prevalent in patients with hypertrophic obstructive cardiomyopathy (HOCM). Inflammatory responses are increased in patients with OSA, meanwhile, inflammation is also associated with adverse outcomes in HOCM.

Hypothesis

To investigate the association between severity of OSA and high‐sensitivity C‐reactive protein (hs‐CRP) in patients with HOCM.

Methods

Three hundred and ninteen patients with HOCM who underwent sleep evaluations at Fuwai Hospital were retrospectively included between February 2010 and December 2018. Data from baseline clinical characteristics and polysomnography studies were collected.

Results

OSA was present in 168 (52.7%). Patients with OSA were older, more likely to be male, had a higher body mass index and more clinical comorbidities. Patients with OSA had enlarged left ventricular diameter and similar left ventricular outflow tract obstruction compared with those without. In multivariate logistic analysis, apnea‐hypopnea index (OR, 1.024; 95% CI, 1.005‐1.044; P = .014), oxygen desaturation index (OR, 1.025; 95% CI, 1.004‐1.046; P = .018) and lowest oxygen saturation (OR, 0.951; 95% CI, 0.915‐0.989; P = .011) were independently associated with high risk hs‐CRP (>3 mg/L) after adjusting for confounders. In addition, decreasing lowest oxygen saturation (β = −.159, P = .004) was also independently correlated with increasing hs‐CRP concentrations in multivariate linear analysis after adjusting for confounders.

Conclusions

Severity of OSA was independently associated with elevated hs‐CRP levels in patients with HOCM. Further studies are needed to evaluate the effects of treating OSA on hs‐CRP as well as clinical outcomes in these patients.

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.