A case of mitral regurgitation whose nocturnal periodic breathing was improved after mitral valve replacement

Impact of transcatheter edge-to-edge mitral valve repair on central sleep apnoea

Aims

Sleep-disordered breathing (SDB) and its subtype central sleep apnoea (CSA) are highly prevalent in patients with heart failure and associated with worse prognosis. Whereas pharmacological therapy of heart failure has been shown to ameliorate CSA, results from previous studies on the effect of mitral regurgitation therapy on SDB are contradicting. The aim of this study was to assess the impact of transcatheter edge-to-edge mitral valve repair (TEER) on prevalence and severity of CSA.

Methods and results

We enrolled 47 patients undergoing TEER for symptomatic mitral regurgitation in a prospective study. Secondary mitral regurgitation and left ventricular ejection fraction < 50% were present in 79% and 68% of patients, respectively. Respiratory polygraphy was performed before TEER in a compensated condition and four weeks after the procedure. 34 patients completed the follow-up. At baseline, 19 (56%) patients showed moderate-to-severe SDB, of whom 13 (68%) were classified as CSA. Both apnoea-hypopnoea index and percentage of recorded time spent in Cheyne-Stokes respiration strongly decreased from baseline to follow-up (median [IQR] 16 [7–30] vs. 7 [4–15] /h, p = 0.007; 6 [0–34] vs. 0 [0–8] %, p = 0.008). Median relative reduction of central apnoea index was 75% (p = 0.023), while obstructive apnoea index did not change significantly. Increase in stroke volume after TEER and high systolic pulmonary artery pressure at baseline predicted a > 50% reduction of both Apnoea-hypopnoea index and Cheyne-Stokes respiration.

Conclusion

TEER is associated with a significant short-term reduction of CSA and Cheyne-Stokes respiration in high-risk patients, strengthening its value as an effective treatment option for advanced heart failure.

Graphical abstract

Elimination of central sleep apnea by cardiac valve replacement: a continuous follow-up study in patients with rheumatic valvular heart disease

BACKGROUND

Recent studies have suggested that cardiac surgery may affect sleep-disordered breathing (SDB) in chronic heart failure patients. However, the dynamic changes in sleep apnea and heart function after cardiac surgery and the mechanisms responsible for these changes remain unknown.

METHODS

Patients with rheumatic valvular heart disease (RVHD) and SDB were enrolled and followed up at three, six and 12 months after cardiac valve replacement (CVR). Baseline and follow-up clinical data consisting of NYHA classification, 6min walk distance (6-MWD), medications, echocardiography, electrocardiography, chest X-ray, arterial blood gas, lung-to-finger circulation time (LFCT), and sleep data were collected and evaluated.

RESULTS

Twenty-four central sleep apnea (CSA) patients and 15 obstructive sleep apnea (OSA) patients completed three follow-up assessments. Comparison of the baseline parameters between OSA patients and CSA patients showed that CSA patients had a worse baseline cardiac function assessed by higher NYHA class, shorter 6-MWD, larger left atrial diameter, longer LFCT, and enhanced chemosensitivity (higher pH and lower arterial carbon dioxide tension (PaCO2)). A continuous significant elevation in 6-MWD and left ventricular ejection fraction and decrease in NYHA class, plasma BNP, and left atrial diameter were found in both CSA and OSA patients. When comparing CSA and OSA patients, the CSA indices were remarkably reduced at month 3 post CVR and sustained throughout the trial, whereas there were no significant decreases in OSA index and hypopnea index. pH values and LFCT were markedly decreased and PaCO2 markedly increased in patients with CSA at the end of the third months following CVR. These changes were sustained until the end of the trial.

CONCLUSIONS

CSA patients with RVHD had a worse baseline cardiac function, enhanced chemosensitivity and disordered hemodynamic as compared with OSA patients with RVHD. CSA were eliminated after CVR; however, there were no changes in OSA. The elimination of CSA, post CVR, is associated with the combined efficacies of improvement of cardiac function, normalized chemosensitivity, and stabilized hemodynamic.

Prevalence and risk factors of sleep disordered breathing in patients with rheumatic valvular heart disease

STUDY OBJECTIVES

Sleep disordered breathing (SDB) is common in patients with chronic heart failure secondary to non-valvular heart disease; however, the prevalence and characteristics of SDB in patients with rheumatic valvular heart disease (RVHD) are unclear. This study was designed to determine the prevalence, characteristics, and risk factors for SDB in RVHD patients.

METHODS

A cross-sectional study was conducted in 260 RVHD patients. The following data were recorded: types of heart valve lesions, electrocardiographic, echocardiographic, arterial blood gas analysis findings, baseline medication, 6-minute walk test (6MWT) distance, and sleep parameters.

RESULTS

Compared to patients with single leftsided valve lesions, patients with left- and rightsided valve lesions had a higher prevalence of SDB (46.2% vs. 31.2%, p = 0.013); the increased prevalence of SDB only involved central sleep apnea (CSA) (31.1% vs. 14.1%, p = 0.001). Patients with obstructive sleep apnea (OSA) or CSA were older and had a shorter 6MWT distance, lower left ventricle ejection fraction and PaO₂, a longer lung-to-finger circulation time, and a higher prevalence of atrial fibrillation (AF) and hypertension (all p < 0.05) as compared with patients without SDB. Multinomial logistic regression analysis showed that PaO2 ≤ 85 mm Hg was the only risk factor for OSA. Male gender, AF, 6MWT distance ≤ 300 m, PaO₂ ≤ 85 mmHg, and PaCO₂ ≤ 40 mm Hg were risk factors for CSA.

CONCLUSIONS

Patients with RVHD had a high prevalence of SDB (predominantly CSA). RVHD patients with SDB, particularly those who had CSA, manifested more severe symptoms and greater impairment of cardiac function. Assessments of clinical manifestations of cardiac dysfunction may be important for predicting the risk factors for SDB.

Preoperative management of deteriorating mitral regurgitation and heart failure with continuous positive airway pressure

A 75-year-old Japanese woman with acute mitral valve prolapse and regurgitation, that developed one month previously, suffered from intractably progressive congestive heart failure (CHF). However, the emergent surgery was declined, and pharmacological treatment was discontinued due to hypotension and malignant arrhythmia. She was treated with 5-8 cmH2O of continuous positive airway pressure (CPAP) to manage CHF and Cheyne-Stokes respiration during the preoperative period of five weeks, after which plastic surgery of the mitral valve was successfully performed. CPAP can be an effective non-pharmacological treatment for CHF, unloading the left ventricle hydrostatically in order to reduce mitral regurgitation and improve oxygenation.

Conversion from predominant central sleep apnea to obstructive sleep apnea following valvuloplasty in a patient with mitral regurgitation

A few reports have shown that cardiac valve repair may improve central sleep apnea (CSA) in patients with valvular heart disease. It has been suggested that such improvements are associated with the improvement of cardiac function. We report the case of a 67-year-old man with mitral regurgitation, whose CSA converted to predominant obstructive sleep apnea following mitral valvuloplasty in association with a shortening of lung-to-finger circulation time.

Valve repair improves central sleep apnea in heart failure patients with valvular heart diseases

BACKGROUND

Recent studies suggest that treatment of heart failure (HF) could improve cardiac function and sleep apnea syndrome (SAS), but it is unknown how cardiac surgery may affect SAS in HF patients. Relationships between HF with valvular heart diseases and 2 types of SAS (obstructive sleep apnea (OSA) and central sleep apnea (CSA)) were examined. The effects of valve repair surgery on OSA and CSA was also investigated.

METHODS AND RESULTS

Polysomnography, echocardiography and right cardiac catheterization were used to study 150 severe HF patients with mitral valvular and/or aortic valvular diseases. Significant associations between SAS and age, gender, body mass index, or hypertension were observed. The value of the CSA-apnea index (AI) was significantly correlated with pulmonary capillary wedge pressure (PCWP) and mean pulmonary artery pressure (PAP). These associations were not identified for OSA-AI. Valve repair surgery was used to treat 74 patients with severe SAS. The treatment led to a significant improvement in PCWP and mean PAP, and CSA-AI, but not in OSA-AI.

CONCLUSIONS

These findings suggest close associations between CSA and cardiac function in HF patients with valvular heart diseases. Furthermore, improvement of cardiac function with valvular surgery reduces the severity of CSA in HF patients with valvular heart diseases.

Central sleep apnea: implications for congestive heart failure

Congestive heart failure (HF), an exceedingly common and costly disease, is frequently seen in association with central sleep apnea (CSA), which often manifests as a periodic breathing rhythm referred to as Cheyne-Stokes respiration. CSA has historically been considered to be a marker of heart disease, since improvement in cardiac status is often associated with the attenuation of CSA. However, this mirroring of HF and CSA may suggest bidirectional importance to their relationship. In fact, observational data suggest that CSA, associated with repetitive oxyhemoglobin desaturations and surges in sympathetic neural activity, may be of pathophysiologic significance in HF outcomes. In light of the disappointing results from the first large trial assessing therapy with continuous positive airway pressure in patients with CSA and HF, further large-scale interventional trials will be needed to assess the role, if any, of CSA treatment on the outcomes of patients with HF. This review will discuss epidemiologic, pathophysiologic, diagnostic, and therapeutic considerations of CSA in the setting of HF.

Central sleep apnoea syndrome in patients with chronic heart disease: a critical review of the current literature

The prevalence, prognosis, clinical presentation, pathophysiology, diagnosis, and treatment of the central sleep apnoea syndrome (CSAS) are reviewed and its relationship with congestive heart failure (CHF) is discussed. Adequately powered trials are needed with survival and health status as end points to establish whether correction of sleep related breathing abnormalities improves the outcome in patients with CHF.