Self-helped detection of obstructive sleep apnea based on automated facial recognition and machine learning

PURPOSE

The diagnosis of obstructive sleep apnea (OSA) relies on time-consuming and complicated procedures which are not always readily available and may delay diagnosis. With the widespread use of artificial intelligence, we presumed that the combination of simple clinical information and imaging recognition based on facial photos may be a useful tool to screen for OSA.

METHODS

We recruited consecutive subjects suspected of OSA who had received sleep examination and photographing. Sixty-eight points from 2-dimensional facial photos were labelled by automated identification. An optimized model with facial features and basic clinical information was established and tenfold cross-validation was performed. Area under the receiver operating characteristic curve (AUC) indicated the model's performance using sleep monitoring as the reference standard.

RESULTS

A total of 653 subjects (77.2% males, 55.3% OSA) were analyzed. CATBOOST was the most suitable algorithm for OSA classification with a sensitivity, specificity, accuracy, and AUC of 0.75, 0.66, 0.71, and 0.76 respectively (P < 0.05), which was better than STOP-Bang questionnaire, NoSAS scores, and Epworth scale. Witnessed apnea by sleep partner was the most powerful variable, followed by body mass index, neck circumference, facial parameters, and hypertension. The model's performance became more robust with a sensitivity of 0.94, for patients with frequent supine sleep apnea.

CONCLUSION

The findings suggest that craniofacial features extracted from 2-dimensional frontal photos, especially in the mandibular segment, have the potential to become predictors of OSA in the Chinese population. Machine learning-derived automatic recognition may facilitate the self-help screening for OSA in a quick, radiation-free, and repeatable manner.

Fast assessment of left ventricular systolic function in obstructive sleep apnea patients with automated function imaging: Comparison with mitral annular plane systolic excursion

BACKGROUND

Early detection of left ventricular (LV) subclinical dysfunction is clinically relevant before developing irreversible impairment in obstructive sleep apnea (OSA) patients. Mitral annulus plane systolic excursion (MAPSE) is a fast tool for OSA due to high prevalent obesity; another quick but more comprehensive tool is LV global longitudinal stain (GLS) based on automated function imaging (AFI). We therefore aimed to compare the feasibility and reproducibility of AFI to MAPSE in OSA patients, as a good model in whom obesity is common.

METHODS

A comprehensive echocardiographic examination was done in 186 consecutive patients having polysomnography for suspected OSA. MAPSE was measured by using M-mode to calculate excursion of mitral annulus. GLS was derived by offline analysis of three long-axis views that semi-automatically detects LV endocardial boundary, which is adjusted manually as necessary with AFI measurement. Variability of AFI and MAPSE were compared among the different subgroups.

RESULTS

Despite a relatively high obesity rate (42.9%), the feasibility of AFI was 94% (175/186) and that of 100% in MAPSE. AFI showed excellent correlation (r = .882) superior to MAPSE (r = .819) between the Expert and Beginner. Intra- and inter- observer variability of AFI and MAPSE in Bland-Altman analysis were 5.5% and 6.5%; 6.2% and 8.8%, respectively. In repeated measurements, AFI showed higher intra-class correlation (ICC = .95) than MAPSE (ICC = .87) (p < 0.05). Furthermore, analysis showed that AFI was feasible even in more obese patients (BMI≥28 kg/m² ).

CONCLUSIONS

Even in obese patients with OSA, AFI-GLS is feasible and more reliable for less expert operators than MAPSE in detecting LV longitudinal dysfunction.

Passive Prescription of Secondary Prevention Medical Therapy during Index Hospitalization for Acute Myocardial Infarction Is Prevalent and Associated with Adverse Clinical Outcomes

Secondary prevention therapy reduces death and reinfarction after acute myocardial infarction (AMI), but it is underutilized in clinical practice. Mechanisms for this therapeutic gap are not well established. In this study, we have explored and evaluated the impact of passive continuation compared to active initiation of secondary prevention therapy for AMI during the index hospitalization. For this purpose, we have analyzed 1083 consecutive patients with AMI to a tertiary referral hospital in Hong Kong and assessed discharge prescription rates of secondary prevention therapies (aspirin, beta-blockers, statins, and ACEI/ARBs). Multivariate analysis was used to identify independent predictors of discharge medication, and Kaplan-Meier survival curve was used to evaluate 12-month survival. Overall, prescription rates of aspirin, beta-blocker, statin, and ACEI/ARBs on discharge were 94.8%, 64.5%, 83.5%, and 61.4%, respectively. Multivariate analysis showed that prior use of each therapy was an independent predictor of prescription of the same therapy on discharge: aspirin (odds ratio (OR) = 4.8, 95% CI = 1.9-12.3, P < 0.01), beta-blocker (OR = 2.5, 95% CI = 1.8-3.4, P < 0.01); statin (OR = 8.3, 95% CI = 0.4-15.7, P < 0.01), and ACEI/ARBs (OR = 2.9, 95% CI = 2.0-4.3, P < 0.01). Passive continuation of prior medication was associated with higher 1-year mortality rates than active initiation in treatment-naïve patients (aspirin (13.7% vs. 5.7%), beta-blockers (12.9% vs. 5.6%), and statins (11.0% vs. 4.6%); all P < 0.01). Overall, the use of secondary prevention medication for AMI was suboptimal. Our findings suggested that the practice of passive continuation of prior medication was prevalent and associated with adverse clinical outcomes compared to active initiation of secondary preventive therapies for acute myocardial infarction during the index hospitalization.

Association Between OSA and Quantitative Atherosclerotic Plaque Burden: A Coronary CT Angiography Study

BACKGROUND

Limited evidence is available regarding the association between OSA and coronary plaque assessed by using quantitative coronary CT angiography.

RESEARCH QUESTION

Are there any associations between OSA severity-related indexes and the presence and burden of coronary plaque?

STUDY DESIGN AND METHODS

Cross-sectional data from 692 patients who underwent sleep monitoring and coronary CT angiography were used for this study. Of these patients, 120 (17.3%) underwent polysomnography, and 572 (82.7%) underwent respiratory polygraphy. Multivariable logistic and linear regression analyses were used to investigate the associations of OSA severity-related indexes with the presence, volume, and composition of plaque.

RESULTS

In multivariable analyses, patients with moderate to severe OSA were more likely to have coronary plaques (P = .037), and plaques were more likely to contain a noncalcified plaque (NCP) component (P = .032) and a low-density NCP (LD NCP) component (P = .030). Furthermore, the apnea-hypopnea index and oxygen desaturation index as continuous variables were both associated with the presence of plaque, NCP, and LD NCP (all, P < .05). Multivariable linear regression models showed that moderate to severe OSA was associated with NCP volume (β = 50.328; P = .042) and LD NCP volume (β = 15.707; P = .011). Moreover, the apnea-hypopnea index (P = .015), oxygen desaturation index (P = .005), and percentage of nighttime with oxygen saturation < 90% (P = .017) were all significant predictors of LD NCP volume. Compared with those with no or mild OSA, patients with severe OSA had a significantly higher total plaque volume (P = .036), NCP volume (P = .036), and LD NCP volume (P = .013).

INTERPRETATION

OSA was independently associated with the presence and burden of coronary plaque, which suggests an increased risk of coronary events.

CLINICAL TRIAL REGISTRATION

Chinese Clinical Trial Registry; No. ChiCTR-ROC-17011027; http://chictr.org.cn.

Subclinical left ventricular systolic dysfunction detected in obstructive sleep apnea with automated function imaging and its association with nocturnal hypoxia

BACKGROUND

Early detection of left ventricular (LV) dysfunction is crucial in obstructive sleep apnea (OSA) due to its close relationship with cardiovascular diseases. Global longitudinal strain (GLS) derived from automated function imaging (AFI) can precisely assess global longitudinal function. The aim of this study was to determine if LV GLS was reduced in patients with OSA and a normal LV ejection fraction (LVEF) and to assess any associated determinants.

METHODS

Polysomnography (PSG) and echocardiography were done in consecutive patients with suspected OSA and normal LVEF in this prospective study. Patients were divided into two groups according to apnea-hypopnea index (AHI) (Group 1, normal or mild OSA: AHI < 15/h; Group 2, moderate-to-severe OSA: AHI ≥ 15/h). Clinical, PSG, and echocardiographic parameters were compared between the two groups and the associated factors were investigated.

RESULTS

Of 425 consecutive patients, 244 were analyzed after exclusions. Patients in Group 2 had significantly worse GLS than those in Group 1 (p < 0.001). The prevalence of GLS reduction (defined as < - 19.7%) was 25% and 76%, respectively (χ² = 34.19, p < 0.001). Nocturnal lowest pulse oxygen saturation (SpO₂), AHI, body mass index (BMI), and gender were associated with GLS reduction (all p < 0.05). Further multivariate analysis showed that the lowest SpO₂ (OR: 2.15), gender (OR: 2.45), and BMI (OR: 2.66) remained independent (all p < 0.05), and the lowest SpO₂ was the most powerful determinant (χ² = 33.0, p < 0.001) in forward regression analysis. The intra- and inter-operator variability for AFI and coefficient of repeatability was low even in those with relatively poor images.

CONCLUSIONS

In patients with normal LVEF, more severe OSA was associated with a worse GLS. The major determinants were lowest nocturnal SpO₂, gender, and obesity, but not AHI. GLS can be rapidly and reliably assessed using AFI.

Obstructive sleep apnoea, intermittent hypoxia and heart failure with a preserved ejection fraction

Obstructive sleep apnoea (OSA) is recognised to be a potent risk factor for hypertension, coronary heart disease, strokes and heart failure with a reduced ejection fraction. However, the association between OSA and heart failure with a preserved ejection fraction (HFpEF) is less well recognised. Both conditions are very common globally.It appears that there are many similarities between the pathological effects of OSA and other known aetiologies of HFpEF and its postulated pathophysiology. Intermittent hypoxia induced by OSA leads to widespread stimulation of the sympathetic nervous system, renin-angiotensin-aldosterone system and more importantly a systemic inflammatory state associated with oxidative stress. This is similar to the consequences of hypertension, diabetes, obesity and ageing that are the common precursors to HFpEF. The final common pathway is probably via the development of myocardial fibrosis and structural changes in collagen and myocardial titin that cause myocardial stiffening. Thus, considering the pathophysiology of OSA and HFpEF, OSA is likely to be a significant risk factor for HFpEF and further trials of preventive treatment should be considered.

Dietary Fiber Intake, Myocardial Injury, and Major Adverse Cardiovascular Events Among End-Stage Kidney Disease Patients: A Prospective Cohort Study

Introduction

Dialysis patients are frequently advised to restrict fruit and vegetable intake due to their high potassium content. This study aimed to evaluate the association between dietary fiber intake and major adverse cardiovascular events (MACE) among dialysis patients.

Methods

A total of 219 prevalent dialysis patients were prospectively recruited from a major university teaching hospital and regional dialysis center in Hong Kong. Dietary fiber intake estimated using a 7-day locally validated food frequency questionnaire was examined in relation to a primary composite outcome of MACE over a follow-up period of 4 years.

Results

A total of 127 patients were complicated with 1 or more MACE. In the multivariable Cox regression analysis, every 1 g higher fiber intake, and every 1 g/d per 1000 kcal higher fiber intake density were associated with an 11% (95% confidence interval [CI]: 0.81-0.97) and a 13% lower risk of MACE (95% CI: 0.77-0.99), respectively, independent of clinical, demographic, biochemical, hemodynamic, adequacy parameters, dietary protein, energy intake, inflammatory, and cardiac markers. Patients in the lower tertile of fiber intake density showed an increased hazard for MACE (adjusted hazard ratio: 1.78; 95% CI: 1.13-2.80) than those in the upper tertile.

Conclusion

Higher fiber intake and higher fiber intake density may be associated with less inflammation, less myocardial hypertrophy, injury, and lower risk of MACE in dialysis patients. These data form an important basis for a randomized controlled trial to examine fiber supplementation on cardiovascular outcomes in the dialysis population.

Changes of ventricular and peripheral performance in patients with heart failure and normal ejection fraction: insights from ergometry stress echocardiography

AIMS

We assessed the left ventricular (LV) and peripheral performance at rest and during exercise in healthy and heart failure subjects with normal ejection fraction (HFNEF) or with reduced ejection fraction (HFREF).

METHODS

All subjects received echocardiography at rest and with bicycle Ergometer exercise. The exercise images for two-dimensional speckle tracking were acquired with submaximal heart rate of 90-100 beats/min, while images for M-mode and tissue Doppler imaging were stored with attainment of >85% of predicted heart rate.

RESULTS

A total of 80 HFNEF, 50 HFREF and 50 controls were studied. There was progressive decrease of two-dimensional global circumferential, radial and longitudinal strains (GCS, GRS and GLS), M-mode and tissue Doppler imaging long-axis parameters from controls, HFNEF to HFREF patients (all P < 0.05) at rest and on exercise. The degree of exercise-induced, long-axis augmentation (GLS and M-mode long axis excursion) decreased progressively from controls, HFNEF to HFREF subjects (all P < 0.05), while the increase in GCS and GRS was similar in all groups. The ventricular-arterial coupling ratio did not change in HFREF but reduced in HFNEF and controls during exercise (P < 0.01). All subjects had a similar resting heart rate, but patients exhibited chronotropic non-competence during exercise (P < 0.001).

CONCLUSIONS

Ventricular and peripheral dysfunction was evident in HFNEF at rest and deteriorated during exercise. The HFNEF patients had significantly impaired long-axis augmentation at stress that was intermediate between HFREF patients and controls. These findings have relevance to generation of symptoms on exercise in both HFNEF and HFREF.

Micro-RNA and mRNA myocardial tissue expression in biopsy specimen from patients with heart failure

AIMS

There is increasing evidence that changes in microRNA (miRNA) expression occur in chronic heart failure and these may be involved in the pathogenesis. In this study we have explored the expression of selected myocyte and fibroblast-related microRNAs and messenger RNAs (mRNAs) that are associated with hypertrophy, apoptosis and fibrosis in biopsy specimens from patients with relatively new onset heart failure compared to a group of patients without heart failure.

METHODS AND RESULTS

Myocardial biopsy specimens taken from Chinese patients presenting with recent heart failure were compared with a group of patients without heart failure undergoing routine cardiac surgery (n=34). miRNAs (miR-1, -21, -23, -29, -30, -130, -133, -195, -199, -208, and -320) and corresponding mRNA expression were measured by real-time quantitative-PCR method. miR-1, -21, -23, -29, -130, -195 and -199 were significantly up-regulated in the heart failure group when compared to those without heart failure (all p<0.01). However, miR-30, -133, -208 and -320 were not significantly different. Related mRNAs (casp3, coll I, coll III and TGF) were also significantly up-regulated (all p<0.05) in the heart failure group.

CONCLUSION

Certain selected microRNAs involved in apoptosis, hypertrophy and fibrosis are up-regulated in the myocardium of patients with a clinical history of heart failure compared to those without. These specific miRNAs may be the most suitable for circulating biomarkers in the early stages of chronic heart failure and possibly future therapeutic targets.

Left ventricular long-axis performance during exercise is an important prognosticator in patients with heart failure and preserved ejection fraction

BACKGROUND

Although many prognostic variables have been reported, the risk stratification of patients with heart failure and preserved ejection fraction (HFPEF) has long been controversial due to considerable discordance. Ergometry stress echocardiography may provide a more clinical relevant evaluation in HFPEF. We aimed at evaluating the prognostic value of echocardiographic parameters during exercise in HFPEF patients.

METHODS

Comprehensive echocardiographic examination with symptom-limited exercise testing on a semi-recumbent and tilting bicycle Ergometer (Lode BV, Groningen, the Netherlands) was performed on 80 consecutive HFPEF patients (aged 66±8years; 64% male). The exercise images for two-dimensional (2D) speckle tracking analysis were acquired with heart rate of 90-100bpm, while exercise images for tissue Doppler imaging (TDI) and M-mode echocardiography were stored with attainment of >85% of maximal age-predicted heart rate. All patients were followed up for 3years after stress echocardiography for all-cause mortality and/or heart failure (HF) hospitalization.

RESULTS

During the follow-up, 43 (54%) patients reached the combined end point: 5 (6%) patients died, and another 38 (48%) patients experienced HF hospitalizations. Univariate predictors were: decreased resting left atrial ejection fraction (LAEF), lower peak heart rate, elevated E/e' ratio, reduced TDI myocardial velocities, and impaired 2D global longitudinal strain (GLS) during exercise. Only impaired GLS (hazard ratio [HR] 0.79, 95% confidence interval [CI] 0.67 to 0.91) remained independent after multivariate analysis (p=0.008).

CONCLUSIONS

More than half of the HFPEF patients died or were hospitalized for HF at 3-year follow-up and this was significantly related to impaired left ventricular long-axis function during exercise.

Impaired Left Ventricular Apical Rotation is Associated with Disease Activity of Psoriatic Arthritis

Objective.

Although early cardiovascular (CV) involvement has been found in patients with psoriatic arthritis (PsA), few studies have related this to PsA disease activity. The aim of our study was to evaluate left ventricular (LV) mechanics using novel, more sensitive techniques based on assessment of LV rotation for the detection of impaired LV function in patients with PsA correlated with disease-related risk factors.

Methods.

Seventy-six patients with PsA and 24 healthy control subjects were enrolled, including 33 patients without any CV risk factors. All participants underwent conventional echocardiography and 2-dimensional speckle tracking imaging. Global longitudinal, apical circumferential, and radial strain, and apical rotation and maximal untwisting rate during early diastole were measured.

Results.

Although patients with PsA had normal LV ejection fraction, the myocardial deformation in multidimensional planes was impaired. Based on the cutoff point derived from the apical rotation of control subjects, 81% of the patients had subclinical systolic and/or diastolic dysfunction. Similar prevalence was found in patients without CV risk factors. Spearman correlation demonstrated a relationship between Disease Activity Score in 28 joints (r = 0.299, p = 0.011), erythrocyte sedimentation rate (r = 0.309, p = 0.008), and impaired apical rotation, even after adjusting for age and hypertension. No correlation was found between longitudinal, radial, and circumferential strain and disease activity.

Conclusion.

Subclinical impaired myocardial deformation was common in patients with PsA even without CV risk factors. Apical rotation was associated with the status of PsA disease activity. These new speckle tracking echocardiography techniques can detect subclinical myocardial involvement in PsA.

What can three-dimensional speckle-tracking echocardiography contribute to evaluate global left ventricular systolic performance in patients with heart failure?

PURPOSE

Three-dimensional speckle-tracking echocardiography (3D-STE) is a newly developed technique to evaluate left ventricular (LV) deformation by measuring the area strain (AS) of endocardial surface that combines information from both longitudinal (LS) and circumferential strain (CS). We performed a study to examine myocardial deformation in patients with heart failure (HF) using 3D-STE.

METHOD

A total of 149 subjects including 58 patients with HF and preserved ejection fraction (HFPEF), 45 patients with HF and reduced ejection fraction (HFREF), and 46 normal subjects were prospectively studied by 3D-STE.

RESULT

After adjusting for age, gender and BSA, global CS, LS, radial strain (RS) and AS derived from 3D-STE in patients with HFPEF were significantly higher than their counterparts in patients with HFREF (all p<0.001), but lower than that in normal subjects (all p<0.05). In addition, among all the strain parameters, global AS exhibited the highest correlation with LV ejection fraction (y=1.243x+6.332, r=0.982, p<0.001) and the best intra- (ICCs: 0.986, p<0.001) and inter-observer variability (ICCs: 0.978, p<0.001) than other parameters of 3D strain (CS: 0.981 and 0.974; LS: 0.908 and 0.841; RS: 0.946 and 0.915; all p<0.001).

CONCLUSIONS

Measurement of endocardial surface AS based on 3D-STE technique is reproducible and proves to be accurate and comprehensive in assessing the global LV performance and multidirectional deformation of the LV myocardium in HF patients.

Quantification of left ventricular performance in different heart failure phenotypes by comprehensive ergometry stress echocardiography

BACKGROUND

We evaluated the left ventricular (LV) performance in patients with heart failure and preserved ejection fraction (HFPEF) during exercise as compared to those with heart failure and reduced ejection fraction (HFREF) and healthy subjects.

METHODS

All subjects received echocardiographic (Vivid7, GE Healthcare) examination with symptom-limited exercise testing on a semi-recumbent and tilting bicycle ergometer (Lode BV, Netherlands). The exercise images for 2-dimensional (2D) speckle tracking were acquired with heart rate of 90-100 bpm, while exercise images for tissue Doppler imaging (TDI) and M-mode echocardiography were stored with attainment of >85% of maximal age-predicted heart rate.

RESULTS

Stress echocardiographic examinations were performed in 40 HFPEF (aged 65 ± 9 years; 53% male), 40 HFREF (aged 62 ± 9 years; 90% male) and 30 normal controls (aged 56 ± 5 years; 33% male). Trends of progressive decline in 2D global longitudinal, circumferential and radial strains (GLS, GCS and GRS); TDI septal s' and Sm; and M-mode mitral annular plane systolic excursion (MAPSE) were observed from control, HFPEF to HFREF groups (p<0.05 for all). LV twist was preserved in HFPEF but reduced in HFREF patients as compared to normal controls (p<0.05). Diastolic function measured by TDI septal e', Em and septal E/e' progressively decreased from controls, HFPEF to HFREF patients (all p<0.05). Stroke volumes and cardiac indices (LVSI & LVCI) were preserved in HFPEF but deteriorated in HFREF than controls.

CONCLUSIONS

This study provides the reference values of LV performance during exercise in HFPEF and knowledge about these changes provide important insights for future clinical studies.

Heart failure with preserved or reduced ejection fraction in patients treated with peritoneal dialysis

BACKGROUND

Heart failure is one of the most frequent complications in dialysis patients. However, little is known of the significance of the entity "heart failure with preserved ejection fraction" (HFPEF) in this population. This study aimed to determine the prevalence, clinical profiles, and long-term outcomes of peritoneal dialysis patients with HFPEF.

STUDY DESIGN

Prospective cohort study.

SETTING & PARTICIPANTS

220 patients treated with peritoneal dialysis were recruited from a university teaching hospital in Hong Kong.

PREDICTOR

Heart failure was defined clinically based on the presence of: (1) symptoms and signs, including dyspnea, increased jugular venous pressure, and basal crepitations; (2) radiographic evidence of pulmonary venous congestion or interstitial edema; and (3) resolution of symptoms, signs, and radiographic changes with hypertonic peritoneal dialysis exchanges. Based on a combination of clinical history of heart failure and echocardiography-derived ejection fraction, patients were classified as having no heart failure, HFPEF, and heart failure with reduced ejection fraction (HFREF).

OUTCOMES

All-cause mortality, cardiac death, heart failure, and fatal or nonfatal cardiovascular events.

MEASUREMENTS

All patients underwent 2-dimensional echocardiography and tissue Doppler imaging at baseline and were followed up prospectively for clinical events for 4 years.

RESULTS

86 (39%) patients had heart failure, of whom 54.7% had preserved ejection fraction ≥50% and 45.3% had reduced ejection fraction <50%. Patients with HFPEF were intermediate between those with no heart failure and those with HFREF in terms of blood pressure, prevalence of coronary artery disease, diabetes, cardiac biomarkers, left ventricular mass, volume, and ratio of early mitral inflow velocity to peak mitral annulus velocity. In the multivariable Cox regression analysis, patients with HFPEF showed an increased adjusted HR for cardiac death (2.57; 95% CI, 1.20-5.50), heart failure (HR, 2.25; 95% CI, 1.28-3.96), and fatal or nonfatal cardiovascular event (HR, 2.01; 95% CI, 1.26-3.21) compared with those with no heart failure, but the risk was lower compared with those with HFREF.

LIMITATIONS

The study included prevalent peritoneal dialysis patients and may introduce survival bias.

CONCLUSIONS

HFPEF is common in peritoneal dialysis patients (∼55% of all heart failure) and is associated with increased risk of mortality and adverse cardiovascular outcomes compared with those with no heart failure, although the risk was lower than in patients with HFREF. This entity needs to be more recognized in peritoneal dialysis patients.

Exercise-induced torsional dyssynchrony relates to impaired functional capacity in patients with heart failure and normal ejection fraction

BACKGROUND

Left ventricular (LV) systole and diastole are intimately dependent on myocardial torsion, which involves coupling between myocardial rotation (twisting in systole and untwisting in diastole) and longitudinal motion. Heart failure with normal ejection fraction (HFNEF) is known to involve exercise-induced wall motion abnormalities, but torsion on exercise has not been explored. We hypothesised that torsional dyssynchrony may also be involved and be exaggerated by exercise.

METHODS AND RESULTS

67 patients (age 73±7 years, 45 female) with HFNEF and 38 controls underwent cardiopulmonary exercise testing and echocardiography at rest and on supine exercise. Analysis of three plane motions was performed using speckle tracking and tissue Doppler imaging. Torsional dyssynchrony was quantified as the SD of the time to peak systolic motion (SDSM) (basal and apical rotation, longitudinal and radial displacement); the time difference between peak twist and peak longitudinal displacement (twist-longitudinal motion delay, TLMD) and the ratio of untwist to longitudinal extension (UT:LE). At rest, HFNEF patients had similar SDSM, TLMD and UT:LE compared with controls. Exercise was associated with significantly more dyssynchrony in the HFNEF patients (SDSM 38.8±27.6 ms vs 25.9±15.5 ms, p=0.02; TLMD 28.4±46.2 ms vs 2.9±31.2 ms, p=0.005 and UT:LE 10.4±15.3 vs 3.3±3.8, p=0.022). The SDSM correlated positively with LV wall thickness (r=0.31, p=0.015) and negatively with peak oxygen consumption (r=-0.299, p=0.01) and changes in stroke volume on exercise (r=-0.371, p=0.001).

CONCLUSIONS

HFNEF involves exercise-induced torsional dyssynchrony in systole and diastole, which relates to LV hypertrophy as well as exercise capacity.

Cardiac contractility modulation for heart failure: a meta-analysis of randomized controlled trials

BACKGROUND

Cardiac contractility modulation (CCM) emerges as a promising device treatment for heart failure (HF). This meta-analysis aimed to systematically review the latest available randomized evidence on the effectiveness and safety of CCM in HF.

METHODS

The Cochrane Central Register of Controlled Trials, MEDLINE, and EMBASE were searched in November 2011 to identify eligible randomized controlled trials comparing CCM with sham treatment or usual care. Primary outcomes of interest were all-cause mortality, all-cause hospitalizations, and adverse effects. Risk ratios (RRs) and 95% confidence intervals (CIs) were calculated for dichotomous data using a random-effects model.

RESULTS

Three studies enrolling 641 participants were included. Pooled analysis showed that, compared to control, CCM did not significantly improve all-cause mortality (n = 629, RR 1.19, 95% CI 0.50-2.86, P = 0.69), nor was there a favorable effect in all-cause hospitalizations. No increase in adverse effects with CCM was observed.

CONCLUSIONS

Meta-analysis of data from small randomized trials suggests that CCM, although with no clear benefits in improving clinical outcomes, is not associated with worsening prognosis. Large, well-designed trials are needed to confirm its role in HF patients for whom cardiac resynchronization therapy is contraindicated or unsuccessful.

SLICC/ACR damage index independently associated with left ventricular diastolic dysfunction in patients with systemic lupus erythematosus

Left ventricular (LV) diastolic dysfunction has been reported in both active and inactive systemic lupus erythematosus (SLE) patients without clinical evidence of cardiovascular disease. However, the relationship between the long-term inflammatory burden reflected by the SLICC/ACR damage index and LV diastolic function has not been studied. Eighty-two SLE patients and 82 controls matched for age, sex, body mass index, blood pressure and heart rate underwent echocardiography with tissue Doppler imaging (TDI). LV diastolic function was estimated by the myocardial early diastolic velocity (E') at the lateral annulus. There were 51 patients (62.2%) with nephritis, 23 patients (28.0%) with hypertension, 21 patients (25.6%) with vasculitis, 16 patients (19.5%) with pulmonary hypertension, 4 patients (4.9%) with cerebrovascular disease and 2 patients (2.4%) with diabetes mellitus. Sixty-two patients (75.6%) were taking prednisone and 35 patients (42.7%) used a immunosuppressant. Forty-five patients (54.8%) had active disease and suffered from disease-related end-organ damage. Patients with SLICC/ACR damage index ≥1 had more evidence of LV diastolic dysfunction with lower lateral annulus E' (9.6 ± 3.4 vs 12.9 ± 3.5 cm/s, p < 0.001) than those without. In addition, the proportion of patients with abnormal LV myocardial relaxation (defined as lateral E' < 10.0 cm/s) (51.1% vs 16.2%, χ(2) = 10.8, p = 0.001) were significantly higher. Multivariate analysis showed that the SLICC/ACR damage index ≥1 was independently associated with LV diastolic dysfunction (OR = 3.80, 95%CI: 1.21-11.95, p = 0.023) after adjusting for hypertension, disease duration and medical therapy. This may suggest that the overall inflammatory burden in SLE, as reflected by SLICC/ACR damage index, is associated with the development of diastolic dysfunction in SLE patients.

Acute effects of right ventricular apical pacing on left atrial remodeling and function

BACKGROUND

The acute effects of right ventricular apical (RVA) pacing on left atrial (LA) function in patients with normal ejection fraction are not clear.

METHODS

A total of 94 patients (age 68.1 ± 11.1 years, 26 men) with implanted RVA-based dual-chamber pacemakers were recruited into this study. Patients who were pacemaker-dependent, in persistent atrial fibrillation or left ventricular ejection fraction <45% were excluded. Echocardiography (iE33, Philips, Andover, MA, USA) was performed during intrinsic ventricular conduction (V-sense) and RVA pacing (V-pace) with 15 minutes between switching modes. The total maximal LA volume (LAV(max)), preatrial contraction volume (LAV(pre)), and minimal volume (LAV(min)) were assessed by area-length method. Peak systolic, early diastolic, and peak late diastolic (atrial contractile) velocity (Sm-la, Em-la, and Am-la) and strain (ɛs-la, ɛe-la, and ɛa-la) were measured by color-coded tissue Doppler imaging (TDI) in four mid-LA walls at apical four- and two-chamber views.

RESULTS

During V-pace, LA volumes increased significantly compared with V-sense (LAV(max): 52.0 ± 18.8 vs 55.2 ± 21.1 mL, P = 0.005; LAV(pre): 39.8 ± 16.4 vs 41.3 ± 16.6 mL, P = 0.014; LAV(min): 27.4 ± 14.0 vs 29.1 ± 15.1 mL, P = 0.001). TDI parameters showed significant reduction in Sm-la and Em-la. Furthermore, ɛs-la, ɛe-la, and ɛa-la decreased significantly, especially in patients with preexisting diastolic dysfunction (all P < 0.01).

CONCLUSIONS

RVA pacing acutely induced LA enlargement and impaired atrial contractility. Patients with preexisting diastolic dysfunction may be more vulnerable to develop LA dysfunction and remodeling after acute RVA pacing.

Albumin levels predict survival in patients with heart failure and preserved ejection fraction

AIMS

Low serum albumin is common in patients with systolic heart failure and is associated with increased mortality. However, the relationship between albumin and outcome in patients with heart failure and preserved ejection fraction (HFPEF) is not known. The aim of this study was to investigate the effect of serum albumin level on survival in patients with HFPEF.

METHODS AND RESULTS

We studied 576 consecutive HFPEF patients (left ventricular ejection fraction ≥50%) admitted to our hospital from 2006 to 2009. Standard demographics, transthoracic echocardiography, and routine blood testing including albumin levels were obtained shortly after admission. Outcome was assessed at 1 year after admission. Hypoalbuminaemia (≤34 g/L) was detected in 160 (28%) at admission; and all patients were then divided into hypoalbuminaemia and non-hypoalbuminaemia groups. In the hypoalbuminaemia group, the prevalence of chronic renal failure history, serum creatinine, and urea nitrogen levels were higher when compared with those without hypoalbuminaemia (all P < 0.05). Kaplan-Meier analysis showed that patients with hypoalbuminaemia had a significantly lower survival rate (53% vs. 84%, log-rank χ(2) = 53.3, P < 0.001) and a higher rate of cardiovascular death (21.8% vs. 8.9%, log-rank χ(2) = 19.7, P < 0.001) when compared with those without hypoalbuminaemia. Cox regression further revealed that hypoalbuminaemia, a history of cerebrovascular disease, and older age were the most powerful independent predictors of all-cause mortality in HFPEF patients at 1 year.

CONCLUSIONS

Hypoalbuminaemia is common in HFPEF patients and is associated with increased risk of death. Renal dysfunction may be the main pathophysiological mechanism underlying hypoalbuminaemia in HFPEF patients.

The pathophysiology of heart failure with preserved ejection fraction: from molecular mechanisms to exercise haemodynamics

The pathophysiology of HfpEF is complex. In this review we discuss the molecular aspects of HfpEF as well as the profoundly disturbed haemodynamics with particular focus on exercise haemodynamic abnormalities.

Prevalence and determinants of incomplete right atrial reverse remodeling after device closure of atrial septal defects

Whether the relief of chronic right atrial (RA) volume load by device closure of an atrial septal defect (ASD) normalizes RA size is unknown. The present study evaluated the prevalence and determinants of incomplete RA reverse remodeling (RAR) after ASD closure in adults. Transthoracic echocardiography was performed in 44 consecutive patients with secundum ASD (age 43 ± 17 years, 10 men) without a history of atrial arrhythmia shortly before and at 3 months after device closure of ASD. The pulmonary/systemic flow ratio was derived using invasive oximetry. The RA size had significantly decreased at 3 months of follow-up (RA volume index [RAVI] 52 ± 29 to 27 ± 17 ml/m(2), p <0.001). Incomplete RAR (defined as a RAVI of ≥21 ml/m(2)) was detected in 25 patients (57%) after closure. They were older, had a larger pulmonary/systemic flow ratio, a higher pulmonary arterial systolic pressure, more tricuspid regurgitation, and larger RA, left atrial, and right ventricular sizes before closure than those with a normalized right atrium. Before closure, RAVI was the only independent determinant for incomplete RAR (odds ratio 1.115, 95% confidence interval 1.019 to 1.220; p = 0.018). A cutoff value of RAVI of ≥40 ml/m(2) has a sensitivity of 84% and specificity of 72% in the receiver operating characteristic curve. The preclosure RAVI correlated moderately with the shunt-duration index, calculated by multiplying the age to pulmonary/systemic flow ratio (r = 0.64, p <0.01). In conclusion, incomplete RAR occurred in >1/2 of the adult patients at 3 months after ASD device closure and was related to excessive preclosure RA dilation.