Association between coronary spastic angina pectoris and obstructive sleep apnea

Association Between Obstructive Sleep Apnea and Cardiovascular Events in Acute Coronary Syndrome Patients With or Without Revascularization - A Prospective Cohort Study

BACKGROUND

The effects of obstructive sleep apnea (OSA) on the prognosis of acute coronary syndrome (ACS) without revascularization remain unclear, so the aim of the present study was to elucidate the association of OSA with subsequent cardiovascular events in ACS patients with and without revascularization.Methods and Results: We prospectively recruited hospitalized ACS patients undergoing sleep monitoring between June 2015 and January 2020. OSA was defined as an apnea-hypopnea index ≥15 events/h. The primary endpoint was a major adverse cardiovascular and cerebrovascular event (MACCE), including cardiovascular death, myocardial infarction, stroke, ischemia-driven revascularization, or hospitalization for unstable angina or heart failure. Among 1,927 patients, 52.6% had OSA and 69.4% underwent revascularization. During a 2.9-year follow-up (1.5-3.6 years), the risk of MACCE was similar in patients with or without revascularization. OSA was an independent predictor of MACCE in the non-revascularization group (22.6% vs. 14.6%; hazard ratio (HR) 1.861; 95% confidence interval (CI) 1.239-2.796; P=0.003) but not in revascularization group (22.3% vs. 19.3%; HR 1.135; 95% CI 0.882-1.460; P=0.324). The incremental risk in the non-revascularization group was attributable to more hospitalizations for unstable angina (14.2% vs. 8.6%; HR 1.896; 95% CI 1.124-3.199; P=0.016).

CONCLUSIONS

For patients with ACS, OSA was independently associated with higher risk of recurrent cardiovascular events among patients without revascularization but not among patients undergoing revascularization. The benefits of suitable OSA treatment for patients without revascularization need further investigation.

The Association of Obstructive Sleep Apnea in Ischemia with No Obstructive Coronary Artery Disease - A Pilot Study

Obstructive sleep apnea (OSA) is increasingly recognized to be a risk factor for cardiovascular disease. This pilot study assessed the association of OSA and invasive coronary microvascular function in patients with ischemia with no obstructive coronary artery disease (INOCA). Forty-two patients with angina, were prospectively screened at a single tertiary centre covering the northern metropolitan area of South Australia, from February 2018 to December 2020 (ACTRN12618000149268). Forty patients were invited into to this observational study after coronary angiography demonstrated INOCA and functional coronary vasomotor disorder (n = 40). Twenty one participants subsequently underwent a sleep study for OSA diagnosis while 9 participants had prior formal diagnosis of OSA (ACTRN12618000227291). Of the 30 participants with OSA data, 87% (n = 26) had a diagnosis of OSA. Accordingly, 11 with mild severity, 7 with moderate severity and 8 with severe OSA. No OSA was observed in 4 participants. Participants with OSA were older [61.4±8.7 vs 49.9±9.7, P = 0.002] with similar clinical characteristics for the pattern and severity of angina and other co-morbidities. 73.3% (n = 22) had abnormal functional disorders of the epicardial coronary arteries and/or coronary microcirculation. On multivariate analysis, OSA was the only statistically significant association with functional coronary microvascular disorders [OR 53.95, 1.41 -2065.01, P = 0.032]. This study provided an observation of a significant correlation between INOCA with abnormal coronary vasomotor function and OSA in an Australian cohort. This correlation supports a possible pathophysiological interplay between these two conditions that needs to be further evaluated. The benefit of treatment of OSA in this subset remains unknown.

Retinal microvascular changes in patients with coronary artery disease and apnea

BACKGROUND

Optical coherence tomography angiography (OCT-A) allowed visualization of capillary level of retina; however, the relationship between coronary vascular status and retinal microvascular changes in patients with apnea is not known well. Our aim was to assess the retinal OCT-A parameters in patients with ischemia and angiographically proven microvascular disease and compare them with obstructive coronary disease in patients with apnea.

METHODS

Our observational study included 185 eyes of 185 patients, 123 eyes of patients with apnea (72 eyes from mild OSAS, 51 eyes from moderate to severe OSAS) and 62 eyes from healthy controls. Radial scans of the macula and OCT-A scans of the central macula (superficial (SCP) and deep (DCP) capillary plexuses) were performed on all participants. All participants had documented sleep apnea disorder within 2 years prior to coronary angiography. Patients were grouped by severity of apnea and coronary atherosclerosis (50 % stenosis cut-off value for obstructive coronary artery disease). Patients presented with myocardial ischemia and without coronary artery occlusion (<50 % diameter reduction or FFR > 0.80) constitute the microvascular coronary artery (INOCA) group.

RESULTS

Compared to healthy controls, patients with apnea showed deterioration in vascular density in all regions of the retina, regardless of obstructive or microvascular coronary artery disease on the ischemia background. This study has provided important observations of a high prevalence of INOCA in patients with OSAS and the presence of OSAS was a significant independent predictor of functional coronary artery disease. The relative decreases in vascular densities were more pronounced in the DCP layer according to SCP layer of macula. Only FAZ area values were significantly different according to the severity of OSAS (0.27 (0.11-0.62) and 0.23 (0.07-0.50) (p = 0.012)).

CONCLUSIONS

In patients with apnea, OCT-A can be used as a noninvasive tool to define coronary artery involvement, with similar retinal microvascular changes both in obstructive and microvascular coronary artery group. In patients with OSAS, we observed a high prevalence of microvascular coronary disease, supporting pathophysiological role of OSAS in ischemia of this group of patients.

Obstructive Sleep Apnea in Coronary Artery Disease

Obstructive sleep apnea (OSA) is a common sleep-related breathing disorder, characterised by obstruction of upper airways during sleep, resulting in repetitive breathing pauses accompanied by oxygen desaturation and arousal from sleep. OSA patients commonly suffers from poor sleep quality and reduced quality of life. Further, OSA is associated with cardiovascular risk factors and linked independently to both structural coronary artery disease (CAD) as well as functional CAD. Structural CAD is depicted by atherosclerosis (either obstructive or non-obstructive) of the epicardial coronary arteries, while functional CAD, encompasses the spectrum of coronary vasomotor disorders (CVD). There are multiple factors including intermittent hypoxia (IH), sleep fragmentation, and intra-thoracic pressure swings leading to altered cardiopulmonary vascular hemodynamic. IH and its downstream maladaptive responses has the most robust evidence for OSA's role in atherogenesis. CPAP therapy has been linked with reduction in major adverse cardiovascular events in meta-analyses, however, pivotal randomised controlled trials failed to demonstrate its significance.

Predictors of Obstructive Sleep Apnoea (OSA) Population in the Coronary Angiogram Database of South Australia (CADOSA)

Obstructive sleep apnoea (OSA) is increasingly recognized to be a risk factor for cardiovascular disease. This study assessed the prevalence and clinical predictors of OSA in patients undergoing coronary angiography. Consecutive patients undergoing coronary angiography in South Australian public hospitals from 2015 to 2018 were included. Clinical details for consecutive patients undergoing coronary angiography in South Australian public hospitals were captured by the Coronary Angiogram Database of South Australia (CADOSA) registry staff, with OSA identified by patient report. Among the 9,885 patients undergoing coronary angiography for the investigation of chest pain, 11% (n = 1,089) were documented as having OSA. Independent clinical predictors of OSA included male gender (OR 2.22, 1.86-2.65, P < 0.001), diabetes mellitus (OR 1.84, 1.58-2.14, P < 0.001), depression (OR 1.81, 1.55-2.12, P < 0.001), prior heart failure (OR 1.63, 1.22-2.18, P = 0.001), hypertension (OR 1.61, 1.32-1.95, P ≤ 0.001), asthma (OR 1.61, 1.34-1.93, P < 0.001), not a current smoker (OR 1.60, 1.30-1.96, P < 0.001), dyslipidaemia (OR 1.46, 1.22-1.76, P < 0.001), non-acute coronary syndrome presentation (OR 1.45, 1.25-1.69, P < 0.001), chronic lung disease (OR 1.40, 1.12-1.73, P = 0.003), cerebrovascular disease (OR 1.36, 1.07-1.73, P = 0.012), non-obstructive coronary artery disease (NOCAD) (OR 1.30, 1.10-1.55, P = 0.003) and atrial fibrillation/flutter (OR 1.30, 1.06-1.60, P = 0.012). Finally, stable angina (32.1% vs 22.7%) and NOCAD (29.1% vs 26.3%, P = 0.051) were trended more common in patients with OSA versus no OSA. In addition to established risk factors for OSA, this study found NOCAD to be independent predictor of OSA; especially in those presenting with a stable angina presentation. This suggests that coronary vasomotor disorders may be associated with OSA, although further detailed studies are required.

Sleep apnoea in Australian men: disease burden, co-morbidities, and correlates from the Australian longitudinal study on male health

Background

Obstructive sleep apnoea is a common disorder with under-rated clinical impact, which is increasingly being recognised as having a major bearing on global disease burden. Men are especially vulnerable and become a priority group for preventative interventions. However, there is limited information on prevalence of the condition in Australia, its co-morbidities, and potential risk factors.

Methods

We used data from 13,423 adult men included in the baseline wave of Ten to Men, an Australian national study of the health of males, assembled using stratified cluster sampling with oversampling from rural and regional areas. Those aged 18–55 years self-completed a paper-based questionnaire that included a question regarding health professional-diagnosed sleep apnoea, physical and mental health status, and health-related behaviours. Sampling weights were used to account for the sampling design when reporting the prevalence estimates. Odds ratios were used to describe the association between health professional-diagnosed sleep apnoea and potential correlates while adjusting for age, country of birth, and body-mass index (BMI).

Results

Prevalence of self-reported health professional-diagnosed sleep apnoea increased from 2.2 % in age 18–25 years to 7.8 % in the age 45–55 years. Compared with those without sleep apnoea, those with sleep apnoea had significantly poorer physical, mental, and self-rated health as well as lower subjective wellbeing and poorer concentration/remembering (p < 0.001 for all). Sleep apnoea was significantly associated with older age (p < 0.001), unemployment (p < 0.001), asthma (p = 0.011), chronic obstructive pulmonary disease/chronic bronchitis (p = 0.002), diabetes (p < 0.001), hypercholesterolemia (p < 0.001), hypertension (p < 0.001), heart attack (p < 0.001), heart failure (p < 0.001), angina (p < 0.001), depression (p < 0.001), post-traumatic stress disorder (p < 0.001), other anxiety disorders (p < 0.001), schizophrenia (p = 0.002), overweight/obesity (p < 0.001), insufficient physical activity (p = 0.006), smoking (p = 0.005), and high alcohol consumption (p < 0.001).

Conclusion

Health professional-diagnosed sleep apnoea is relatively common, particularly in older males. Associations between sleep apnoea and cardiovascular, metabolic, respiratory, and psychiatric disorders have important clinical and public health implications. As men are especially vulnerable to sleep apnoea as well as some of its chronic co-morbidities, they are potentially a priority group for health interventions. Modifiable lifestyle related factors such as smoking, alcohol consumption, level of physical activity and BMI are possible key foci for interventions.

Positive airway pressure in patients with coronary artery disease and obstructive sleep apnea syndrome

AIMS

We designed a prospective nonrandomized study aiming at assessing the impact of continuous positive airway pressure (CPAP) after a new diagnosis of obstructive sleep apnea syndrome (OSAS) in patients with coronary artery disease (CAD).

METHODS

Consecutive patients referred to coronary angiography underwent an overnight sleep study during their hospital stay. Among those with angiographically confirmed CAD and a new diagnosis of moderate or severe OSAS, we compared the 3-year major adverse cardiac or cerebrovascular event (MACCE)-free survival stratified by CPAP at discharge.

RESULTS

Of 496 patients undergoing an overnight sleep study, 129 had angiographically confirmed CAD and presented with moderate or severe OSAS. The incidence of 3-year MACCE was significantly lower in the CPAP-treated group (n = 17) than in the untreated group (n = 112; 12 vs. 44%, P = 0.02). After adjusting for differences in baseline characteristics, CPAP was significantly associated with a decreased risk of MACCE [adjusted hazard ratio 0.18, 95% confidence interval (CI) 0.04-0.78, P = 0.02]. Among men, CPAP was associated with a significant 3-year risk reduction in MACCE (adjusted hazard ratio 0.12, 95% CI 0.02-0.87, P = 0.04), whereas no significant benefit of CPAP was seen in women (adjusted hazard ratio 2.1, 95% CI 0.10-41.6, P = 0.63). The statistical interaction between CPAP and sex trended to be significant (adjusted P for interaction = 0.10).

CONCLUSION

In patients with OSAS and CAD, the initiation of CPAP is associated with a significant reduction in MACCE compared with patients left untreated.

Impact of obstructive sleep apnea on left atrial functional and structural remodeling beyond obesity

BACKGROUND

To evaluate the left atrial (LA) volume and function of obese patients with/without obstructive sleep apnea (OSA) and its association with left ventricular (LV) diastolic function independent of obesity.

METHODS

LA volumetric and functional parameters were measured by 2-dimensional and strain echocardiography in 49 obese (body mass index ≥ 25 kg/m(2)) subjects (24 non-OSA and 25 OSA).

RESULTS

OSA group showed larger maximal LA volume indexed for body surface area, larger volume before atrial contraction, a reduction in the LA passive emptying fraction, and an increase in the LA active emptying fraction with no significant change in LA total emptying fraction. Mitral annular early diastolic velocity (Ea) was significantly reduced, whereas the ratio of mitral valve early diastolic velocity (E) to Ea (E/Ea) and late diastolic velocity (Aa) were significantly increased in OSA group. Although the mean peak late diastolic strain rate had not shown any differences, the LA mean peak systolic strain/strain rate, and mean peak early diastolic strain rate were significantly lower in the OSA group. Apnea-hypopnea index (AHI) of the OSA patients was significantly correlated with E/Ea (r=0.67, p<0.001). There is a significant correlation between LA active emptying volume index and E/Ea (r=0.77, p<0.001), and between LA passive emptying volume index and E/Ea (r=-0.51, p=0.009).

CONCLUSION

LA structural and functional remodeling was significantly correlated with the severity of OSA and LV diastolic filling pressure. OSA impaired LA wall compliance and passive contraction independent of obesity.

Impact of obstructive sleep apnea on the global myocardial performance beyond obesity

We aimed to assess the impact of obstructive sleep apnea (OSA) on the left ventricular (LV) function independent of obesity using the myocardial performance index (Tei index) and the global longitudinal LV strain (GLS) and its reversibility after surgery. Twenty-five newly diagnosed OSA patients, normal weight (n = 15) and obese (body mass index [BMI] ≥ 25; n = 20) controls without OSA were enrolled and underwent transthoracic echocardiographic evaluation. The OSA and obese groups had a significantly comparable increased BMI and LV chamber dimension, prolonged isovolumic relaxation time, reduced early mitral filling velocity, and increased late mitral filling velocity and Tei index as compared to the normal weight group. However, GLS was significantly reduced only in the OSA group (-16.5 ± 1.9%) as compared to the normal weight group (-20.6 ± 2.0%, P < 0.001) and obese group (-19.1 ± 2.5%, P < 0.001). As a treatment, 13 of 25 patients underwent surgical modification, and the follow-up echocardiogram revealed significantly improved Tei index and GLS as compared to baseline (0.37 ± 0.06 and -18.9 ± 3.3% vs. 0.42 ± 0.04 and -16.3 ± 2.4%, P = 0.006 and 0.031, respectively), which was comparable to the obese controls. A reduction in the apnea-hypopnea index had a significant effect on the improvement in the GLS (r = 0.73, P < 0.001). LV systolic and diastolic function significantly deteriorated in the patients with OSA beyond obesity, and an improvement in the LV function was observed within 6 months after the surgical modification. GLS is considered to be one of the parameters that can be used in the early detection of LV systolic dysfunction in patients with OSA and a normal ejection fraction.

Therapeutic procedures for coronary vasospasm-induced polymorphic ventricular tachycardia

Coronary vasospasm is an unusual cause of angina and myocardial ischemia, with the potential to provoke acute myocardial infarction, malignant cardiac arrhythmias, and sudden cardiac death. The diagnosis is largely clinical and requires a high index of suspicion. Provocation studies are rarely performed due to the risks of the procedure and the relatively low incidence of disease. A subset of patients does not respond to conventional medical therapy and a paucity of evidence exists to guide therapy. While generally believed a multifocal phenomenon, there have been reports of successful treatment of focal, refractory vasospasm with coronary stent implantation. Furthermore, consideration of an implantable cardioverter defibrillator is warranted when vasospasm is complicated by lethal ventricular arrhythmias.