Long-term prognostic significance of left atrial volume in acute myocardial infarction

Atrial Fibrillation, Atrial Myopathy, and Thromboembolism: The Additive Value of Echocardiography and Possible New Horizons for Risk Stratification

Atrial fibrillation (AF) is the most common cardiac sustained arrhythmia, and it is associated with increased stroke and dementia risk. While the established paradigm attributes these complications to blood stasis within the atria and subsequent thrombus formation with cerebral embolization, recent evidence suggests that atrial myopathy (AM) may play a key role. AM is characterized by structural and functional abnormalities of the atria, and can occur with or without AF. Moving beyond classifications based solely on episode duration, the 4S-AF characterization has offered a more comprehensive approach, incorporating patient's stroke risk, symptom severity, AF burden, and substrate assessment (including AM) for tailored treatment decisions. The "ABC" pathway emphasizes anticoagulation, symptom control, and cardiovascular risk modification and emerging evidence suggests broader benefits of early rhythm control strategies, potentially reducing stroke and dementia risk and improving clinical outcomes. However, a better integration of AM assessment into the current framework holds promise for further personalizing AF management and optimizing patient outcomes. This review explores the emerging concept of AM and its potential role as a risk factor for stroke and dementia and in AF patients' management strategies, highlighting the limitations of current risk stratification methods, like the CHA2DS2-VASc score. Echocardiography, particularly left atrial (LA) strain analysis, has shown to be a promising non-invasive tool for AM evaluation and recent studies suggest that LA strain analysis may be a more sensitive risk stratifier for thromboembolic events than AF itself, with some studies showing a stronger association between LA strain and thromboembolic events compared to traditional risk factors. Integrating it into routine clinical practice could improve patient management and targeted therapies for AF and potentially other thromboembolic events. Future studies are needed to explore the efficacy and safety of anticoagulation in AM patients with and without AF and to refine the diagnostic criteria for AM.

Chronic mild to moderate mitral regurgitation will not have an impact on left atrial strain parameters in the pediatric population

BACKGROUND

Left atrial strain (LAS) analysis represents a newer non-invasive, sensitive and specific technique for assessing left atrial (LA) function and early detection of its deformation and dysfunction. However, its applicability in mitral regurgitation (MR) in pediatric population remains unexplored, raising pertinent questions regarding its potential role in evaluating the severity and progression of the disease.

OBJECTIVE

To investigate the impact of chronic MR in children and adolescents on LA remodeling and function.

METHODS

The study included 100 participants. Patients with primary and secondary chronic MR lasting at least 5 years fit our inclusion criteria. The exclusion criteria from the study were: patients with functional mitral regurgitation due to primary cardiomyopathies, patients with artificial mitral valve, patients with MR who had previously undergone surgery due to obstructive lesions of the left heart (aortic stenosis, coarctation of the aorta), patients with significant atrial rhythm disorders (atrial fibrillation, atrial flutter). The echocardiographic recordings were conducted by two different cardiologists. Outcome data was reported as mean and standard deviation (SD) or median and interquartile range (Q1-Q3).

RESULTS

The study included 100 participants, of whom 50 had MR and the remaining 50 were without MR. The average age of all participants was 15.8 ± 1.2 years, with a gender distribution of 37 males and 63 females. There was a significant difference in the values of LA volume index (LAVI), which were higher in patients with MR (p= 0.0001), S/D ratio (and parameters S and D; p= 0.001, p= 0.0001, p= 0.013), mitral annulus radius (p= 0.0001), E/A ratio (p= 0.0001), as well as septal e' (m/s), lateral e' (m/s), and average E/e' ratio, along with the values of TV peak gradient and LV global longitudinal strain (%). There was no significant difference in LA strain parameters, nor in LA stiffness index (LASI).

CONCLUSION

Our findings revealed significant differences in several echocardiographic parameters in pediatric patients with MR relative to those without MR, providing insight into the multifaceted cardiac structural and functional effects of MR in this vulnerable population.

Predicting impaired cardiopulmonary exercise capacity in patients with atrial fibrillation using a simple echocardiographic marker

BACKGROUND

Exercise intolerance is a common symptom associated with atrial fibrillation (AF). However, echocardiographic markers that can predict impaired exercise capacity are lacking.

OBJECTIVE

This study aimed to investigate the association between echocardiographic parameters and exercise capacity assessed by cardiopulmonary exercise testing in patients with AF.

METHODS

This single-center prospective study enrolled patients with AF who underwent echocardiography and cardiopulmonary exercise testing to evaluate exercise capacity at a tertiary center for AF management from 2020 to 2022. Patients with valvular heart disease, reduced left ventricular ejection fraction, or documented cardiomyopathy were excluded.

RESULTS

Of the 188 patients, 134 (71.2%) exhibited impaired exercise capacity (peak oxygen consumption ≤85%), including 4 (2.1%) having poor exercise capacity (peak oxygen consumption <50%). Echocardiographic findings revealed that these patients had an enlarged left atrial end-systolic diameter (LA); smaller left ventricular end-diastolic diameter (LVEDD); and increased relative wall thickness, tricuspid regurgitation velocity, and LA/LVEDD and E/e' ratios. In addition, they exhibited lower peak systolic velocity of the mitral annulus and LA reservoir strain. In the multivariate regression model, LA/LVEDD remained the only significant echocardiographic parameter after adjustment for age, sex, and body mass index (P = .020). This significance persisted even after incorporation of heart rate reserve, N-terminal pro-B-type natriuretic peptide level, and beta-blocker use into the model.

CONCLUSION

In patients with AF, LA/LVEDD is strongly associated with exercise capacity. Further follow-up and validation are necessary to clarify its clinical implications in patient care.

Implications of left atrial volume index in patients with three-vessel coronary disease: A 6.6-year follow-up cohort study

BACKGROUND

Risk assessment and treatment stratification for three-vessel coronary disease (TVD) remain challenging. This study aimed to investigate the prognostic value of left atrial volume index (LAVI) with the Synergy Between Percutaneous Coronary Intervention with Taxus and Cardiac Surgery (SYNTAX) score II, and its association with the long-term prognosis after three strategies (percutaneous coronary intervention [PCI], coronary artery bypass grafting [CABG], and medical therapy [MT]) in patients with TVD.

METHODS

This study was a post hoc analysis of a large, prospective cohort of patients with TVD in China, that aimed to determine the long-term outcomes after PCI, CABG, or optimal MT alone. A total of 8943 patients with TVD were consecutively enrolled between 2004 and 2011 at Fuwai Hospital. A total of 7818 patients with available baseline LAVI data were included in the study. Baseline, procedural, and follow-up data were collected. The primary endpoint was major adverse cardiac and cerebrovascular events (MACCE), which was a composite of all-cause death, myocardial infarction (MI), and stroke. Secondary endpoints included all-cause death, cardiac death, MI, revascularization, and stroke. Long-term outcomes were evaluated among LAVI quartile groups.

RESULTS

During a median follow-up of 6.6 years, a higher LAVI was strongly associated with increased risk of MACCE (Q3: hazard ratio [HR] 1.20, 95% confidence interval [CI] 1.06-1.37, P = 0.005; Q4: HR 1.85, 95%CI 1.64-2.09, P <0.001), all-cause death (Q3: HR 1.41, 95% CI 1.17-1.69, P <0.001; Q4: HR 2.54, 95%CI 2.16-3.00, P <0.001), and cardiac death (Q3: HR 1.81, 95% CI 1.39-2.37, P <0.001; Q4: HR 3.47, 95%CI 2.71-4.43, P <0.001). Moreover, LAVI significantly improved discrimination and reclassification of the SYNTAX score II. Notably, there was a significant interaction between LAVI quartiles and treatment strategies for MACCE. CABG was associated with lower risk of MACCE than MT alone, regardless of LAVI quartiles. Among patients in the fourth quartile, PCI was associated with significantly increased risk of cardiac death compared with CABG (HR: 5.25, 95% CI: 1.97-14.03, P = 0.001).

CONCLUSIONS

LAVI is a potential index for risk stratification and therapeutic decision-making in patients with three-vessel coronary disease. CABG is associated with improved long-term outcomes compared with MT alone, regardless of LAVI quartiles. When LAVI is severely elevated, PCI is associated with higher risk of cardiac death than CABG.

Ratio of early transmitral inflow velocity to early diastolic strain rate predicts atrial fibrillation following acute myocardial infarction

The ratio of early transmitral filling velocity to early diastolic strain rate (E/SRe) has been proposed as a new non-invasive measurement of left ventricular filling pressure. We aimed to investigate the ability of E/SRe to predict atrial fibrillation (AF) after ST-elevation myocardial infarction (STEMI). This was a prospective cohort study of patients (n = 369) with STEMI. Patients underwent an echocardiographic examination a median of two days after pPCI. By echocardiography, transmitral early filling velocity (E) was measured by pulsed-wave Doppler, and early diastolic strain rate (SRe) was measured by speckle tracking of the left ventricle. E was indexed to SRe and the early myocardial relaxation velocity (e') to obtain the E/SRe and E/e', respectively. The endpoint was new-onset AF. During follow-up (median 5.6 years, IQR: 5.0-6.1 years), 23 (6%) of the 369 patients developed AF. In unadjusted analyses, both E/SRe and E/e' were significantly associated with AF [E/SRe: HR = 1.06; (1.03-1.10); p < 0.001, per 10 increase] and [E/e': HR = 1.11 (1.05-1.17); p < 0.001, per 1 increase] and had equal Harrell's C-statistic of 0.71. However, only E/SRe remained an independent predictor after multivariable adjustments for clinical and echocardiographic parameters [E/SRe: HR = 1.06 (1.00-1.11); p = 0.044, per 10 increase]. E/SRe was further significantly associated with AF in patients with E/e' < 14 HR = 1.09 (1.01-1.17); p = 0.030, per 10 increase), also after multivariable adjustments. E/SRe is an independent predictor of AF in STEMI patients, even in subjects with seemingly normal filling pressure.

Left atrial function index predicts poor outcomes in acute myocardial infarction patients treated with percutaneous coronary intervention

Background and aims

The left atrial function index (LAFI) is an index that combines the left atrial emptying fraction, adjusted left atrial volume and stroke volume. The prognostic value of LAFI in acute myocardial infarction (AMI) patients treated with percutaneous coronary intervention (PCI) is unknown. This study aims to determine whether LAFI predicts prognosis in AMI patients treated with PCI.

Methods

Patients with newly diagnosed AMI who were treated with PCI at Hunan Provincial People's Hospital from March 2020 to October 2021 were prospectively enrolled. All patients underwent transthoracic echocardiography (TTE) at baseline and follow-up. The endpoint events included rehospitalization due to unstable angina, nonfatal myocardial infarction, rehospitalization due to heart failure and cardiovascular death.

Results

A total of 368 patients with AMI (92 women; mean age, 61.45 ± 11.91 years) were studied with a median follow-up of 14 ± 6.58 months. Sixty-nine patients had endpoint events. Patients who presented with events had a significantly lower LAFI than patients without events (34.25 ± 12.86 vs. 48.38 ± 19.42, P < 0.0001). Multivariate Cox analysis demonstrated that LAFI (HR = 0.97 [95% CI: 0.95; 0.99]; P = 0.012) and the Killip classification (HR = 1.51 [95% CI: 1.03; 2.22]; P = 0.034) were independently predictive of endpoint events. Kaplan-Meier survival curves showed that patients with LAFI ≤ 40.17 cm/ml/m2 had higher events than patients with LAFI > 40.17 cm/ml/m2 (HR = 8.53 [95% CI: 4.74; 15.35]; P < 0.0001).

Conclusion

LAFI is a strong and independent predictor of adverse events and can be used for risk stratification in patients with AMI treated with PCI.

Left atrial function index predicts poor outcome in STEMI patients treated with percutaneous coronary intervention

The prognostic value of the left atrial function index (LAFI) in acute ST segment elevation myocardial infarction (STEMI) patients treated with percutaneous coronary intervention (PCI) is unknown. This study sought to determine whether the LAFI predicts prognosis in STEMI patients treated with PCI. Patients with newly diagnosed STEMI who were treated with PCI in Hunan Provincial People's Hospital from March 2020 to October 2020 were prospectively enrolled. All patients underwent transthoracic echocardiography at baseline and follow-up. The endpoint events included rehospitalization due to unstable angina, nonfatal myocardial infarction, rehospitalization due to heart failure and cardiovascular death. A total of 156 STEMI patients treated with PCI were studied with a median follow-up of 14 months. Forty-eight patients had endpoint events. The LAFI had the highest area under the receiver operating characteristic curve (AUC) predicting the endpoint events, with an AUC of 0.90 (95% CI 0.84-0.94). Multivariate Cox analysis demonstrated that only the LAFI (HR: 0.91, 95% CI 0.87-0.96, P < 0.0001) was independently predictive of endpoint events. Kaplan‒Meier survival curves showed that patients with an LAFI ≤ 42.25 cm/cc/m² had more events than patients with an LAFI > 42.25 cm/cc/m² (HR: 19.15, 95% CI 8.90-41.21, P < 0.001). The LAFI is a strong and independent predictor of events in STEMI patients treated with PCI.

Cardiovascular magnetic resonance-derived left atrioventricular coupling index and major adverse cardiac events in patients following acute myocardial infarction

BACKGROUND

Recently, a novel left atrioventricular coupling index (LACI) has been introduced providing prognostic value to predict cardiovascular events beyond common risk factors in patients without cardiovascular disease. Since data on cardiovascular magnetic resonance (CMR)-derived LACI in patients following acute myocardial infarction (AMI) are scarce, we aimed to assess the diagnostic and prognostic implications of LACI in a large AMI patient cohort.

METHODS

In total, 1046 patients following AMI were included. After primary percutaneous coronary intervention CMR imaging and subsequent functional analyses were performed. LACI was defined by the ratio of the left atrial end-diastolic volume divided by the left ventricular (LV) end-diastolic volume. Major adverse cardiac events (MACE) including death, reinfarction or heart failure within 12 months after the index event were defined as primary clinical endpoint.

RESULTS

LACI was significantly higher in patients with MACE compared to those without MACE (p < 0.001). Youden Index identified an optimal LACI cut-off at 34.7% to classify patients at high-risk (p < 0.001 on log-rank testing). Greater LACI was associated with MACE on univariate regression modeling (HR 8.1, 95% CI 3.4-14.9, p < 0.001) and after adjusting for baseline confounders and LV ejection fraction (LVEF) on multivariate regression analyses (HR 3.1 95% CI 1.0-9, p = 0.049). Furthermore, LACI assessment enabled further risk stratification in high-risk patients with impaired LV systolic function (LVEF ≤ 35%; p < 0.001 on log-rank testing).

CONCLUSION

Atrial-ventricular interaction using CMR-derived LACI is a superior measure of outcome beyond LVEF especially in high-risk patients following AMI. Trial registration ClinicalTrials.gov, NCT00712101 and NCT01612312.

Matrix Metalloproteinase-Targeted SPECT/CT Imaging for Evaluation of Therapeutic Hydrogels for the Early Modulation of Post-Infarct Myocardial Remodeling

Following myocardial infarction (MI), maladaptive upregulation of matrix metalloproteinase (MMP) alters extracellular matrix leading to cardiac remodeling. Intramyocardial hydrogel delivery provides a vehicle for local delivery of MMP tissue inhibitors (rTIMP-3) for MMP activity modulation. We evaluated swine 10-14 days following MI randomized to intramyocardial delivery of saline, degradable hyaluronic acid (HA) hydrogel, or rTIMP-3 releasing hydrogel with an MMP-targeted radiotracer (99mTc-RP805), 201Tl, and CT. Significant left ventricle (LV) wall thinning, increased wall stress, reduced circumferential wall strain occurred in the MI region of MI-Saline group along with left atrial (LA) dilation, while these changes were modulated in both hydrogel groups. 99mTc-RP805 activity increased twofold in MI-Saline group and attenuated in hydrogel animals. Infarct size significantly reduced only in rTIMP-3 hydrogel group. Hybrid SPECT/CT imaging demonstrated a therapeutic benefit of intramyocardial delivery of hydrogels post-MI and reduced remodeling of LA and LV in association with a reduction in MMP activation.

Left atrial phasic volumes and functions changes in asymptomatic patients with sarcoidosis: evaluation by three-dimensional echocardiography

BACKGROUND

Cardiac involvement is the leading cause of morbidity and death in patients with sarcoidosis. However, many patients remain asymptomatic until the late-stage. In this study, we investigated the left atrial (LA) phasic volumes and functions changes by three-dimensional (3D) echocardiography measurements in asymptomatic patients with sarcoidosis, which has good correlation with cardiac magnetic resonance imaging.

METHODS

In this cross-sectional study, 44 asymptomatic patients with sarcoidosis and 40 age, sex and BMI-matched healthy volunteers underwent two-dimensional (2D) and 3D-echocardiograpy. Standard echocardiographic and tissue Doppler imaging parameters were obtained. LA phasic volumes were assessed by 3D-echocardiography. From the 3D-echocardiography derived values, LA active, passive, and total emptying fraction (EF) were calculated.

RESULTS

All left ventricular ejection fractions (LVEF) obtained by 2D and 3D-echocardiography were normal (≥50%). While LA diameters (33.36 ± 4.23 vs. 30.57 ± 5.43) and E/e' septal annulus ratios (10.82 ± 1.79 vs. 9.27 ± 1.81) were significantly higher, A-wave (70.80 ± 5.81 vs. 74.51 ± 5.41) and e'septal annular velocities (6.48 ± 1.58 vs. 9.03 ± 1.63) were significantly lower in the sarcoidosis group as compared with control group, respectively. While 3D-echocardiography derived LA-minimum volume indices (LAVImin) (13.89 ± 2.75 vs. 12.23 ± 1.73) were significantly higher, 3D-echocardiography derived LA active EFs (AAEF) (30.78 ± 3.52 vs. 38.52 ± 4.75) and LA total EFs (TAEF) (47.71 ± 7.47 vs. 53.32 ± 5.81) were found to be significantly lower in the sarcoidosis group as compared with control group, respectively.

CONCLUSION

LAVImin, AAEF and TAEF calculated based on LA phasic volumes obtained by 3D-echocardiography may be promising indicators of subclinical cardiac involvement in asymptomatic patients with sarcoidosis.

Composite Echocardiographic Score to Predict Long-Term Survival Following Myocardial Infarction

BACKGROUND

Whilst the left ventricular ejection fraction (LVEF) remains the primary echocardiographic measure widely utilised for risk stratification following myocardial infarction (MI), it has a number of well recognised limitations. The aim of this study was to compare the prognostic utility of a composite echocardiographic score (EchoScore) composed of prognostically validated measures of left-ventricular (LV) size, geometry and function, to the utility of LVEF alone, for predicting survival following MI.

METHODS

Retrospective data on 394 consecutive patients with a first-ever MI were included. Comprehensive echocardiography was performed within 24 hours of admission for all patients. EchoScore consisted of LVEF<50%, left atrial volume index>34 mL/m², average E/e >14, E/A ratio>2, abnormal LV mass index, and abnormal LV end-systolic volume index. A single point was allocated for each measure to derive a score out of 6. The primary outcome measure was all-cause mortality.

RESULTS

At a median follow-up of 24 months there were 33 deaths. On Kaplan-Meier analysis, a high EchoScore (>3) displayed significant association with all-cause mortality (log-rank χ²=74.48 p<0.001), and was a better predictor than LVEF<35% (log-rank χ²=17.01 p<0.001). On Cox proportional-hazards multivariate analysis incorporating significant clinical and echocardiographic predictors, a high EchoScore was the strongest independent predictor of all-cause mortality (HR 6.44 95%CI 2.94-14.01 p<0.001), and the addition of EchoScore resulted in greater increment in model power compared to addition of LVEF (model χ² 56.29 vs 44.71 p<0.001, Harrell's C values 0.83 vs 0.79).

CONCLUSIONS

A composite echocardiographic score composed of prognostically validated measures of LV size, geometry, and function is superior to LVEF alone for predicting survival following MI.

Increased left atrial volume index is associated with more cardiovascular events in patients with acute coronary syndrome: HIJ-PROPER study findings

AIM

To investigate the association between the left atrial volume index (LAVI) and the incidence of cardiovascular events in patients with acute coronary syndrome (ACS) who did not have atrial fibrillation (AF).

METHODS

In this sub-analysis of the HIJ-PROPER study, 226 ACS patients who did not have a history of AF were enrolled. Participants were divided into two groups according to the LAVI cut-off level calculated by receiver operating characteristic (ROC) curve analysis to predict the primary endpoint, and cardiovascular events were compared between groups. The primary endpoint was the first occurrence of all-cause death, non-fatal myocardial infarction, non-fatal stroke, and hospitalization for heart failure.

RESULTS

ROC curve analysis for the occurrence of composite of cardiovascular events indicated a LAVI cut-off point of 34 mL/m² . Based on this, 131 patients (58.0%) were in the LAVI < 34 mL/m² group and 95 (42.0%) were in the LAVI ≥ 34 mL/m² group. Over a median follow-up period of 4.0 years [interquartile range: 3.2, 5.1], cardiovascular events were noted in 7 and 15 patients in the LAVI < 34 mL/m² and LAVI ≥ 34 mL/m² groups, corresponding to an incidence rate of 5.3% and 15.8%, respectively. Patients with a LAVI value ≥ 34 mL/m² had a significantly higher risk of cardiovascular events than those with a LAVI value < 34 mL/m² (hazard ratio: 2.93; 95% confidence interval: 1.19-7.22; P = .014). The tendency was similar after adjusting for several confounders (P = .025).

CONCLUSION

In ACS patients without AF, elevated LAVI was associated with increased cardiovascular events.

CLINICAL TRIAL REGISTRATION

International standard randomized controlled trial (URL: https://www.umin.ac.jp; UMIN000002742).

Left atrial strain: A novel "biomarker" for chronic kidney disease patients?

Cardiovascular disease and chronic kidney disease are frequently inter-connected and this association leads to an exponential growth of cardiovascular risk. This risk is currently underestimated by the existing algorithms and there is a constant need for new markers to predict adverse outcomes in this special population. In general population left atrial strain has emerged as an important tool for both the diagnosis and prognostic stratification, but data regarding its role in chronic kidney disease patients is scarce. The purpose of this review is to summarize the current evidence regarding this matter. Left atrial size and function mirror the duration and severity of increased left ventricular filling pressures. Increased left atrial volume index and impaired left atrial strain parameters are independent predictors for adverse cardiovascular events. Left atrial strain is impaired before changes in volume appear, thus being able to predict both diastolic and systolic function in chronic kidney disease patients. Finally, left atrial strain can identify renal patients with impaired exercise capacity and this could have clinical applications in the rehabilitation of this patients.

Utility of Functional and Volumetric Left Atrial Parameters Derived From Preprocedural Cardiac CTA in Predicting Mortality After Transcatheter Aortic Valve Replacement

Background: Cardiac CTA is required for preprocedural workup before transcatheter aortic valve replacement (TAVR) and can be used to assess functional parameters of the left atrium (LA). Objective: We aimed to evaluate the utility of functional and volumetric LA parameters derived from cardiac CTA to predict mortality in patients with severe aortic stenosis (AS) undergoing TAVR. Methods: This retrospective study included 175 patients with severe AS (median age 79 years; 92 male, 83 female) who underwent cardiac CTA for clinical pre-TAVR assessment. A postdoctoral research fellow calculated maximum and minimum LA volumes using biplane area-length measurements; the values were indexed to body surface area (LAVImax and LAVImin, respectively). LA emptying fraction (LAEF) was automatically calculated. All-cause mortality within a 24-month follow-up period post-TAVR was recorded. To identify parameters predictive of mortality, Cox regression was performed, and results were summarized by hazard ratio (HR) and 95% CI. Harrell's c-index was used to assess model performance. A radiology resident repeated the measurements in a random sample of 20% (n=35) of cases, and interobserver agreement was computed using the intraclass correlation coefficient (ICC). Results: Thirty-eight deaths (22%) were recorded within a median follow-up of 21 months. LAVImax (HR 1.02 [1.01-1.04]; p=.005), LAVImin (HR 1.02 [1.01-1.04]; p<.001), and LAEF (HR 0.97 [0.95-0.99]; p=.002) were predictive of mortality in univariable analysis. After adjusting for clinical parameters, only LAEF (HR 0.97 [0.94-0.99]; p=.02) independently predicted mortality. The c-index of the Society of Thoracic Surgeons Predicted Risk of Mortality (STS-PROM) significantly increased from 0.64 to 0.68, 0.69, and 0.70 when incorporating into the model LAVImax, LAVImin, and LAEF, respectively. ICC for maximum and minimum LA volumes and LAEF ranged from 0.94 to 0.99. Conclusion: LAEF derived from preprocedural cardiac CTA independently predicts mortality in patients with severe AS undergoing TAVR. Clinical impact: Cardiac CTA-derived LA function, evaluated during pre-TAVR workup, can be used to assess preprocedural risk and may improve risk stratification in post-TAVR surveillance.

Left ventricular dyssynchrony assessment using tissue synchronization imaging in acute myocardial infarction

Objectives:

To assess left ventricular (LV) dyssynchrony in patients with ST elevation myocardial infarction (STEMI).

Background:

Mechanical synchronization disorder leads to a decrease in LV ejection fraction (LVEF) and stroke volume, an abnormal distribution of wall tension, and increase in workload during cardiac contraction.

Methods:

We enrolled 56 participants, 36 with acute STEMI and 20 healthy controls. The automatically color-coded time to peak myocardial velocity was measured using a 6mm sample volume, manually positioned within the two-dimensional-tissue strain image of the 12 basal and middle LV segments.

Results:

A significant delay was found between the septal-lateral and septal-posterior walls in patients with STEMI compared to patients in the control group (36.36 vs. −6.0ms, P = 0.036; and 42.7 vs. 23.94ms, P = 0.042, respectively). Furthermore, all segment maximum differences and all segment standard deviation (SD; dyssynchrony index) were found to be significantly higher in the STEMI group (131.28 vs. 95.45ms, P = 0.013; and 44.47 vs. 26.45ms, P = 0.001, respectively). A significant delay between the septal-lateral walls and septal-posterior walls, all segment maximum difference, and all segment SD (dyssynchrony index) were found in patients with complicated STEMI (70.89 vs. 15.83ms, P = 0.038; 57.44 vs. 19.06ms, P = 0.040; 138.11 vs. 100.0ms, P = 0.035; and 45.44 vs. 32.50ms, P = 0.021, respectively). There was a significant negative correlation between tissue synchronization imaging parameters and LVEF, and a positive correlation with LV end systolic dimension.

Conclusion:

Patients with acute STEMI showed significant LV dyssynchrony, which was an independent predictor of inhospital complications.

Effect of Cardiac Rehabilitation on Left Ventricular Diastolic Function in Patients with Acute Myocardial Infarction

Cardiac rehabilitation (CR) improves symptoms and survival in patients with acute myocardial infarction (AMI). We studied the change of diastolic function and its prognostic impact after CR. After reviewing all consecutive AMI patients from January 2012 to October 2015, we analyzed 405 patients (mean, 63.7 ± 11.7 years; 300 males) with baseline and follow-up echocardiographic examinations. We divided them into three groups according to their CR sessions: No-CR group (n = 225), insufficient-CR group (CR < 6 sessions, n = 117) and CR group (CR ≥ 6 sessions, n = 63). We compared echocardiographic parameters of diastolic dysfunction including E/e' ratio > 14, septal e' velocity < 7 cm/s, left atrial volume index (LAVI) > 34 mL/m2, and maximal TR velocity > 2.8 m/s. At baseline, there were no significant differences in all echocardiographic parameters among the three groups. At follow-up echocardiographic examination, mitral annular e' and a' velocities were higher in the CR group (p = 0.024, and p = 0.009, respectively), and mitral E/e' ratio was significantly lower (p = 0.009) in the CR group. The total number of echocardiographic parameters of diastolic dysfunction at the baseline echocardiography was similar (1.29 vs. 1.41 vs. 1.52, p = 0.358). However, the CR group showed the lowest number of diastolic parameters at the follow-up echocardiography (1.05 vs. 1.32 vs. 1.50, p = 0.017). There was a significant difference between the No-CR group and CR group (p = 0.021). The presence of CR was a significant determinant of major adverse cardiovascular events in the univariate analysis (HR = 0.606, p = 0.049). However, the significance disappeared in the multivariate analysis (HR = 0.738, p = 0.249). In conclusion, the CR was significantly associated with favorable diastolic function, with the highest mitral e' and a' velocity, and the lowest mitral E/e' ratio and total number of echocardiographic parameters of diastolic dysfunction at the follow-up echocardiographic examinations in AMI patients.

Prognostic value of left atrial volume index in acute coronary syndrome: A systematic review and meta-analysis

BACKGROUND

In the absence of mitral valve disease, increased left atrial volume (LAV) is a marker of diastolic dysfunction and long-standing elevated left ventricle (LV) pressure. The aim of this study was to assess the role of increased baseline LAV in predicting clinical outcome of patients presenting with acute coronary syndrome (ACS).

METHODS

We systematically searched all electronic databases up to September 2020 in order to select clinical trials and observational studies, which assessed the predictive role of LAV indexed (LAVI) on clinical outcome in patients with ACS. Primary clinical endpoints were as follows: major adverse cardiac events (MACE), all-cause mortality and hospitalization. Secondary endpoints were in-hospital complications.

RESULTS

A total of 2,705 patients from 11 cohort studies with a mean follow-up 18.7 ± 9.8 months were included in the meta-analysis. Patients with low LAVI had low risk for MACE (15.9% vs. 33.7%; p < .01), long-term all-cause mortality (9.14% vs. 18.1%; p < .01), short-term mortality (3.31% vs. 9.38%; p = .02) and lower hospitalization rate (11.6% vs. 25.5%; p < .01) compared to patients with increased LAVI. Atrial fibrillation and cardiogenic shock as in-hospital events were lower (p < .05 for all) in patients with low LAVI but ventricular fibrillation/tachycardia was not different between groups (p = .14).

CONCLUSION

Increased LAVI is an independent predictor of outcome in patients with ACS. Thus, assessment of LA index in these patients is important for better risk stratification and guidance towards optimum clinical management.

Prognostic value of reduction in left atrial size during a follow-up of heart failure: an observational study

OBJECTIVE

The association between sequential changes in left atrial diameter (LAD) and prognosis in heart failure (HF) remains to be elucidated. The present study aimed to investigate the link between reduction in LAD and clinical outcomes in patients with HF.

DESIGN

A multicentre prospective cohort study.

SETTING

This study was nested from the Kyoto Congestive Heart Failure registry including consecutive patients admitted for acute decompensated heart failure (ADHF) in 19 hospitals throughout Japan.

PARTICIPANTS

The current study population included 673 patients with HF who underwent both baseline and 6-month follow-up echocardiography with available paired LAD data. We divided them into two groups: the reduction in the LAD group (change <0 mm) (n=398) and the no-reduction in the LAD group (change ≥0 mm) (n=275).

PRIMARY AND SECONDARY OUTCOMES

The primary outcome measure was a composite of all-cause death or hospitalisation for HF during 180 days after 6-month follow-up echocardiography. The secondary outcome measures were defined as the individual components of the primary composite outcome measure and a composite of cardiovascular death or hospitalisation for HF.

RESULTS

The cumulative 180-day incidence of the primary outcome measure was significantly lower in the reduction in the LAD group than in the no-reduction in the LAD group (13.3% vs 22.2%, p=0.002). Even after adjusting 15 confounders, the lower risk of reduction in LAD relative to no-reduction in LAD for the primary outcome measure remained significant (HR 0.59, 95% CI 0.36 to 0.97 p=0.04).

CONCLUSION

Patients with reduction in LAD during follow-up after ADHF hospitalisation had a lower risk for a composite endpoint of all-cause death or HF hospitalisation, suggesting that the change of LAD might be a simple and useful echocardiographic marker during follow-up.

Different associations between left atrial size and 2.5-year clinical outcomes in patients with anterior versus non-anterior wall ST-elevation myocardial infarction

Objective

To investigate associations between left atrial diameter (LAD) and long-term outcomes in patients with anterior or non-anterior wall ST-elevation myocardial infarction (STEMI).

Methods

Patients with STEMI were included in this secondary analysis of data from a prospective cohort study in which the primary outcome was major adverse cardiovascular event (MACE) occurrence during a 2.5-year follow-up. A LAD cut-off value was obtained through receiver operating characteristic curve analysis. Kaplan-Meier curve and Cox regression analyses were applied. Subgroup Cox regression analysis was also performed, with patients stratified based on left ventricular diastolic diameter (LVEDD, > 55 mm and ≤55 mm). The relationship between LAD and outcomes in patients with anterior or non-anterior wall STEMI was explored using restricted cubic spline functions.

Results

Out of 464 patients, adjusted Cox regression showed that dichotomous (>40 mm) LAD was significantly associated with MACE (hazard ratio 2.978, 95% confidence interval 1.763, 5.030) in patients with anterior wall but not non-anterior wall STEMI. The association was not different between normal and enlarged LVEDD groups.

Conclusions

A left atrium > 40 mm may indicate higher risk of MACE in patients with anterior wall STEMI, even in patients with normal left ventricular structure. This relationship was not observed in patients with non-anterior wall STEMI.

Detection of Left Atrial Enlargement Using a Convolutional Neural Network-Enabled Electrocardiogram

Background: Left atrial enlargement (LAE) can independently predict the development of a variety of cardiovascular diseases.

Objectives: This study sought to develop an artificial intelligence approach for the detection of LAE based on 12-lead electrocardiography (ECG).

Methods: The study population came from an epidemiological survey of heart disease in Guangzhou. Elderly people (3,391) over 65 years old who had both 10-s 12 lead ECG and echocardiography were enrolled in this study. The left atrial (LA) anteroposterior diameter >40 mm on echocardiography was diagnosed as LAE, and the LA anteroposterior diameter was indexed by body surface area (BSA) to classify LAE into different degrees. A convolutional neural network (CNN) was trained and validated to detect LAE from normal ECGs. The performance of the model was evaluated by calculating the area under the curve (AUC), accuracy, sensitivity, specificity, and F1 score.

Results: In this study, gender, obesity, hypertension, and valvular heart disease seemed to be related to left atrial enlargement. The AI-enabled ECG identified LAE with an AUC of 0.949 (95% CI: 0.911–0.987). The sensitivity, specificity, accuracy, precision, and F1 score were 84.0%, 92.0%, 88.0%, 91.3%, and 0.875, respectively. Physicians identified LAE with sensitivity, specificity, accuracy, precision, and F1 scores of 38.0%, 84.0%, 61.0%, 70.4%, and 0.494, respectively. In classifying LAE in different degrees, the AUCs of identifying normal, mild LAE, and moderate-severe LAE ECGs were 0.942 (95% CI: 0.903–0.981), 0.951 (95% CI: 0.917–0.987), and 0.998 (95% CI: 0.996–1.00), respectively. The sensitivity, specificity, accuracy, positive predictive value, and F1 scores of diagnosing mild LAE were 82.0%, 92.0%, 88.7%, 89.1%, and 0.854, while the sensitivity, specificity, accuracy, positive predictive value, and F1 scores of diagnosing moderate-severe LAE were 98.0%, 84.0%, 88.7%, 96.1%, and 0.969, respectively.

Conclusions: An AI-enabled ECG acquired during sinus rhythm permits identification of individuals with a high likelihood of LAE. This model requires further refinement and external validation, but it may hold promise for LAE screening.

Left atrial volume index to left ventricular ejection fraction ratio predicted major adverse cardiovascular event in ST-Elevated myocardial infarction patients during 8 years of follow-up

Objective:

Methods:

Results:

Conclusion:

Long-term Prognostic Value of Cardiac MRI Left Atrial Strain in ST-Segment Elevation Myocardial Infarction

Background Left atrial (LA) dysfunction is associated with morbidity and mortality. To the knowledge of the authors, the relationship of LA strain to long-term prognosis in participants with ST-segment elevation myocardial infarction (STEMI) is unknown. Purpose To evaluate LA strain as a long-term outcome predictor in STEMI in a prospective, multicenter cardiac MRI cohort. Materials and Methods Participants with STEMI who underwent primary percutaneous coronary intervention and cardiac MRI from 10 sites (EARLY-MYO-CMR registry, clinical trial number NCT03768453) were included. The parent study took place between August 2013 and December 2018. LA longitudinal strain and strain rate parameters were derived from cine cardiac MRI by using an in-house semiautomated method. Major adverse cardiac events (MACEs) were defined as cardiovascular death, myocardial reinfarction, hospitalization for heart failure, and stroke. The association between LA performance and MACE was evaluated by using time-dependent receiver operating characteristic analysis, Kaplan-Meier analysis, and multivariable Cox regression analysis. Results A total of 321 participants (median age, 59 years; age range, 27-75 years; 90% men) were included in this study. During median follow-up of 3.7 years, MACE occurred in 76 participants (23.7%). Participants with impaired reservoir (≤22%) and conduit strain (≤10%) had a higher risk of MACE than those with reservoir strain greater than 22% and conduit strain greater than 10% (P < .001). Reservoir strain (hazard ratio, 0.84; 95% confidence interval: 0.77, 0.91; P < .001) and conduit strain (hazard ratio, 0.81; 95% confidence interval: 0.73, 0.89; P < .001) were independent predictors for MACE after adjustment for known risk factors. Finally, LA reservoir and conduit strains provided incremental prognostic value over traditional outcome predictors (Uno C statistic comparing models, 0.75 vs 0.68; P = .04). Conclusion Assessment of left atrial strain, as a measure of left atrial function, provided incremental prognostic information to established predictors in ST-segment elevation myocardial infarction. © RSNA, 2020 Online supplemental material is available for this article. See also the editorial by Kawel-Boehm and Bremerich in this issue.

Left atrial volume index and pulmonary arterial pressure predicted MACE among patients with STEMI during 8-year follow-up: experience from a tertiary center

BACKGROUND

It is important to identify patients that are at high risk following primary percutaneous coronary intervention (P-PCI) for the treatment of ST-segment elevation myocardial infarction (STEMI). Left ventricular ejection fraction (LVEF) is the most important parameter obtained from transthoracic echocardiography (TTE) for risk stratification. The authors evaluated the value of pulmonary artery pressure (PAP) and left atrial volume index (LAVI) for the prediction of major adverse cardiovascular events (MACE) in patients with STEMI that underwent P‑PCI.

METHODS

A total of 92 patients that underwent P‑PCI for STEMI were included in the study. All patients underwent TTE examination before discharge. The composite primary outcome of the study was all-cause mortality and new onset heart failure (HF) during an 8-year follow-up period.

RESULTS

The mean age of patients was 61.6 ± 12.4 years and 15 were female (16.3%). Major adverse cardiovascular events (MACE) defined as all-cause mortality and new onset HF occurred in 30 (41%) patients during a mean of 6 ± 2.7 years of follow-up. In the backward multivariate Cox regression analysis LVEF (odds ratio [OR] = 0.933, 95% confidence interval [CI]: 0.876-0.994, p = 0.031), LAVI (OR = 1.069, 95%CI: 1.017-1.124, p = 0.009), PAP (OR = 1.137, 95% CI: 1.057-1.223, p = 0.001) and creatinine level (OR = 1.730, 95% CI: 1.350-1.223, p = 0.029) were found to independently predict MACE during long-term follow-up. Receiver operating characteristic (ROC) curve analysis was performed, revealing that sPAP >24.5 mm Hg had a sensitivity and specificity of 72 and 66%, respectively; LAVI >31 ml/m² had a sensitivity and specificity of 72.2 and 83.3%, respectively.

CONCLUSION

In patients that underwent P‑PCI for the treatment for STEMI, LVEF, LAVI, PAP and creatinine level independently predicted all-cause mortality and new onset HF during long-term follow-up.

COPD and acute myocardial infarction

COPD is strongly associated with cardiovascular disease, in particular acute myocardial infarction (AMI). Besides shared risk factors, COPD-related factors, such as systemic inflammation and hypoxia, underlie the pathophysiological interaction between COPD and AMI. The prevalence of COPD amongst AMI populations ranges from 7% to 30%, which is possibly even an underestimation due to underdiagnoses of COPD in general. Following the acute event, patients with COPD have an increased risk of mortality, heart failure and arrhythmias during follow-up. Adequate risk stratification can be performed using various imaging techniques, evaluating cardiac size and function after AMI. Conventional imaging techniques such as echocardiography and cardiac magnetic resonance imaging have already indicated impaired cardiac function in patients with COPD without known cardiovascular disease. Advanced imaging techniques such as speckle-tracking echocardiography and T1 mapping could provide more insight into cardiac structure and function after AMI and have proven to be of prognostic value. Future research is required to better understand the impact of AMI on patients with COPD in order to provide effective secondary prevention. The present article summarises the current knowledge on the pathophysiologic factors involved in the interaction between COPD and AMI, the prevalence and outcomes of AMI in patients with COPD and the role of imaging in the acute phase and risk stratification after AMI in patients with COPD.

First-Pass Techniques Applied to Standard Dynamic Cardiac PET: A reappraisal of Old Invasive Techniques to Assess Cardiac Function

Cardiac PET is increasingly performed with dynamic imaging to measure tracer pharmacokinetics in the myocardium. If the early time frames of the PET protocol are sufficiently short and the total amount of injected radioactivity is correctly measured the indicator dilution principle can be applied to PET with most tracers in clinical use, similar to invasive and other noninvasive techniques. The first-pass of the tracer through the heart and lungs can be used to quantify some highly important aspects of cardiovascular function, such as forward cardiac output, transit times, and partial volumes in the central compartments. Additionally, ECG-gated first pass images provide direct access to cardiac volumes and ejection fractions, even for tracers with poor trapping in the myocardial wall, for instance 15O-water. This review summarizes the basic approaches of the indicator dilution principle in clinical use with invasive techniques, and how these techniques can be integrated into a cardiac PET scan.

The left atrium and the right ventricle: two supporting chambers to the failing left ventricle

Heart failure (HF) is mainly caused by left ventricular (LV) impairment of function, hence detailed assessment of its structure and function is a clinical priority. The frequent involvement of the left atrium (LA) and the right ventricle (RV) in the overall cardiac performance has recently gained significant interest with specific markers predicting exercise intolerance and prognosis being proposed. The LA and RV are not anatomically separated from the LV, while the LA controls the inlet the RV shares the interventricular septum with the LV. Likewise, the function of the two chambers is not entirely independent from that of the LV, with the LA enlarging to accommodate any rise in filling pressures, which could get transferred to the RV via the pulmonary circulation. In the absence of pulmonary disease, LA and RV function may become impaired in patients with moderate-severe LV disease and raised filling pressures. These changes can often occur irrespective of the severity of systolic dysfunction, thus highlighting the important need for critical assessment of the function of the two chambers. This review evaluates the pivotal role of the left atrium and right ventricle in the management of HF patients based on the available evidence.

Normal reference intervals for cardiac dimensions and function for use in echocardiographic practice: a guideline from the British Society of Echocardiography

This guideline presents reference limits for use in echocardiographic practice, updating previous guidance from the British Society of Echocardiography. The rationale for change is discussed, in addition to how the reference intervals were defined and the current limitations to their use. The importance of interpretation of echocardiographic parameters within the clinical context is explored, as is grading of abnormality. Each of the following echo parameters are discussed and updated in turn: left ventricular linear dimensions and LV mass; left ventricular volumes; left ventricular ejection fraction; left atrial size; right heart parameters; aortic dimensions; and tissue Doppler imaging. There are several important conceptual changes to the assessment of the heart’s structure and function within this guideline. New terminology for left ventricular function and left atrial size are introduced. The British Society of Echocardiography has advocated a new approach to the assessment of the aortic root, the right heart, and clarified the optimal methodology for assessment of LA size. The British Society of Echocardiography has emphasized a preference to use, where feasible, indexed measures over absolute values for any chamber size.

Etiology of Exercise-Induced Pulmonary Hypertension Can Be Differentiated by Echocardiography - Insight From Patients With Chronic Pulmonary Thromboembolism With Normal Resting Hemodynamics by Balloon Pulmonary Angioplasty

BACKGROUND

Exercise-induced pulmonary hypertension (PH) is often seen in chronic thromboembolic PH (CTEPH) patients with normalized resting hemodynamics, but it is difficult to differentiate precapillary PH as pulmonary vascular dysfunction and post-capillary PH from occult-left ventricular dysfunction (LVD). The aim of this study was to examine whether the exercise-induced elevation of pulmonary arterial wedge pressure (PAWP) can be predicted by the echocardiographic index at rest.Methods and Results:A total of 71 CTEPH patients (67±11 years old, male/female=15/56) treated by pulmonary angioplasty with near-normal pulmonary arterial pressure (PAP) and normal PAWP at rest underwent symptom-limited exercise test using supine cycle ergometer with right heart catheterization. Exercise-induced elevation in PAWP of >20 mmHg during exercise was defined as occult-LVD. Resting echocardiography was performed within 3 months. In the occult-LVD (n=28), PAWP at rest after leg raising for exercise (14±4 vs. 11±3 mmHg, P<0.001), and mean PAP during exercise were higher compared with the non-LVD (n=43). Peak oxygen consumption, cardiac output, and pulmonary vascular resistance at peak exercise did not differ between groups. Left atrial volume index (LAVi) in the occult-LVD was significantly larger (39.7±8.1 vs. 34.4±9.6 mL/m², P=0.017). LAVi correlated with exercise PAWP (r=0.356, P=0.002), but not resting PAWP (r=0.161, P=0.179).

CONCLUSIONS

Larger left atrial volume may reflect the exercise-induced PAWP elevation as occult-LVD in CTEPH patients.

Left Atrial Function with MRI Enables Prediction of Cardiovascular Events after Myocardial Infarction: Insights from the AIDA STEMI and TATORT NSTEMI Trials

Background The role of left atrial (LA) performance in acute myocardial infarction (AMI) remains controversial. Cardiac MRI myocardial feature tracking (hereafter, MRI-FT) is a method used to quantify myocardial function that enables reliable assessment of atrial function. Purpose To assess the relationship between LA function assessed with MRI-FT and major adverse cardiovascular events (MACE) after AMI. Materials and Methods This secondary analysis of two prospective multicenter cardiac MRI studies (AIDA STEMI [NCT00712101] and TATORT NSTEMI [NCT01612312]) included 1235 study participants with ST-elevation myocardial infarction (n = 795) or non-ST-elevation myocardial infarction (n = 440) between July 2008 and June 2013. All study participants underwent primary percutaneous coronary intervention. MRI-FT analyses were performed in a core laboratory by researchers blinded to clinical status to determine LA performance using LA reservoir function peak systolic strain (εs), LA conduit strain (εe), and LA booster pump function active strain (εa). The relationship of LA performance to a MACE within 12 months after AMI was evaluated by using Cox proportional hazards models and area under the receiver operating characteristic curve (AUC). Results Study participants with MACE had worse LA performance parameters compared with study participants without MACE (εs = 21.2% vs 16.2%, εe = 8.8% vs 6.9%, εa = 11.8% vs 10%; P < .001 for all). All atrial parameters were strongly associated with MACE (hazard ratio [HR], εs = 0.9, εe = 0.88, εa = 0.89; P < .001 for all). For εs, a cutoff of 18.8% was identified as the only independent atrial parameter with which to predict MACE after accounting for confounders and established prognostic markers in adjusted analysis (HR, 0.95; P = .02). The εs yielded incremental prognostic value above left ventricular ejection fraction, global longitudinal strain, microvascular obstruction, and infarct size (AUC comparisons, P < .04 for all). Conclusion Feature tracking of cardiac MRI to derive left atrial peak reservoir strain provided incremental prognostic value for major adverse cardiovascular events prediction versus established cardiac risk factors after acute myocardial infarction. © RSNA, 2019 Online supplemental material is available for this article. See also the editorial by Almeida in this issue.

Left atrial diameter in heart failure with left ventricular preserved, mid-range, and reduced ejection fraction

Left atrial (LA) remodeling has been identified to predict atrial fibrillation (AF) and heart failure. However, the role of LA diameter (LAD) in patients with heart failure (HF) with preserved (HFpEF), mid-range (HFmrEF), and reduced ejection fraction (HFrEF) remains poorly understood.A total of 142 patients including 71 subjects with AF (21 of HFpEF, 22 of HFmrEF, and 28 of HFrEF) and 71 ejection fraction (EF)-matched subjects with sinus rhythm (SR) were included in the study. Baseline characteristics and echocardiographic parameters including LAD were compared between both groups as well as among HFpEF, HFmrEF, and HFrEF.In receiver-operating characteristic (ROC) analyses, LAD predicted AF in HFpEF, HFmrEF, and HFrEF [area under the curve (AUC): 0.646; P = .03]. LAD was negatively association with left ventricular ejection fraction while positively with Nt-proNP and left ventricular end-diastolic diameter (regression coefficient: -0.239, P = .004; regression coefficient: 0.191, P = .023; regression coefficient: 0.357, P < .001). In ROC analyses, LAD predicted HFrEF among the 3 categories (AUC: 0.629, P = .01).In the setting of HF, LAD was higher in AF than in and SR, and predicted AF. Furthermore, LAD was associated with severity of HF in HFpEF, HFmrEF, and HFrEF, and also predicted HFrEF.

Atrial mechanics and their prognostic impact in Takotsubo syndrome: a cardiovascular magnetic resonance imaging study

Aims

The exact pathophysiology of Takotsubo syndrome (TTS) remains not fully understood with most studies focussing on ventricular pathology. Since atrial involvement may have a significant role, we assessed the diagnostic and prognostic potential of atrial cardiovascular magnetic resonance feature tracking (CMR-FT) in TTS.

Methods and results

This multicentre study recruited 152 TTS patients who underwent CMR on average within 3 days after hospitalization. Reservoir [total strain εs and peak positive strain rate (SR) SRs], conduit (passive strain εe and peak early negative SRe), and booster pump function (active strain εa and peak late negative SRa) were assessed in a core laboratory. Results were compared with 21 control patients with normal biventricular function. A total of 20 patients underwent follow-up CMR (median 3.5 months, interquartile range 3–5). All patients were approached for general follow-up. Left atrial (LA) but not right atrial (RA) reservoir and conduit function were impaired during the acute phase (εs: P = 0.043, εe: P < 0.001, SRe: P = 0.047 vs. controls) and recovered until follow-up (εs: P < 0.001, SRs: P = 0.04, εe: P = 0.001, SRe: P = 0.04). LA and RA booster pump function were increased in the acute setting (LA-εa: P = 0.045, SRa: P = 0.002 and RA-εa: P = 0.004, SRa: P = 0.002 vs. controls). LA-εs predicted mortality [hazard ratio 1.10, 95% confidence interval (CI) 1.01–1.20; P = 0.037] irrespectively of established cardiovascular risk factors (P = 0.019, multivariate analysis) including left ventricular ejection fraction (LVEF) (area under the curve 0.71, 95% CI 0.55–0.86, P = 0.048).

Conclusion

TTS pathophysiology comprises transient impairments in LA reservoir and conduit functions and enhanced bi-atrial active booster pump functions. Atrial CMR-FT may evolve as a superior marker of adverse events over and above established parameters such as LVEF and atrial volume.

Left Atrial Function Determined by Echocardiography Predicts Incident Heart Failure in Patients With STEMI treated by Primary Percutaneous Coronary Intervention

OBJECTIVES

To assess the comparative effectiveness of left atrial (LA) functional parameters (left atrial emptying fraction (LAEF), left atrial expansion index (LAi) and minimal left atrial volume index (MinLAVI)) with that of LA volume index (LAVI) in predicting heart failure (HF) and death following ST-elevated myocardial infarction (STEMI).

BACKGROUND

HF is common following STEMI. Enlarged LA volume as determined by echocardiography predicts adverse outcome following STEMI. However, whether echocardiographic parameters of LA function, such as LAEF, LAi and MinLAVI, are superior to LAVI for predicting prognosis following STEMI is unknown.

METHODS AND RESULTS

A total of 369 patients with STEMI but without atrial fibrillation or HF who were treated with primary percutaneous coronary intervention were prospectively enrolled in the period between September 2006 and December 2008. Patients underwent echocardiography shortly after STEMI. The maximal and minimal LA volumes were measured using the biplane area-length method. LAVI, MinLAVI (minimal LA volume indexed to body surface area), LAEF ((maximal LA volume-minimal LA volume)/maximal LA volume), and LAi ((maximal LA volume-minimal LA volume)/minimal LA volume) were calculated. The endpoint was a composite consisting of HF or death from any cause. During a median follow-up of 66 months (interquartile range: 50-73 months), 112 patients reached the endpoint (68 HFs, 44 deaths). Following adjustment for clinical, biochemical and echocardiographic variables, only LAEF remained an independent predictor of the composite outcome, whereas LAVI did not (LAEF: HR 1.25, P = 0.043, per 1 SD decrease) (LAVI: HR 1.01, P = 0.91, per 1 SD increase).

CONCLUSION

In patients with STEMI who were treated with primary percutaneous coronary intervention, LAEF, as measured by echocardiography shortly after infarction, was superior to LAVI in predicting incident HF and death.

Relation of Left Atrial Volumes in Patients With Myocardial Infarction to Left Ventricular Filling Pressures and Outcomes

The inter-relationships between minimal and maximal left atrial volume index (LAVI), left ventricular filling pressures and survival have not been well studied. This study aimed to compare LAVImin with LAVImax with respect to (1) relative prognostic value, and (2) correlation with left ventricular end-diastolic pressures (LVEDP), in patients with myocardial infarction (MI). A retrospective study involving consecutive patients with a first-ever MI (n = 419) was undertaken. LAVIs were determined using Simpson's biplane method from 2D echocardiography performed the day after admission. LAVmin ≥ 18 mls/m² and LAVImax ≥ 34 mls/m² were considered enlarged. The primary end point was composite major adverse cardiovascular events (MACE) (death/MI/heart failure). Correlation between LVEDP and LAVI was assessed in 120 patients who underwent echocardiography and cardiac catheterization either simultaneously (n = 30) or same-day (n = 90). At a median follow-up of 24 months, there were 61 MACE events. On Cox proportional hazards multivariate analysis incorporating significant clinical predictors and LVEF, whereas both LAVImin ≥ 18 mls/m² (hazard ratio 3.15 [95% confidence interval 1.70 to 5.54], p <0.001) and LAVImax ≥ 34 mls/m² (hazard ratio 1.79 [95% confidence interval 1.02 to 3.14], p = 0.041) were independent predictors of MACE, LAVImin showed a stronger association. Intermodel comparisons of the model chi-square and Harrell's C-statistic confirmed better prognostication with LAVImin. In the invasive cohort, because LAVImin and LAVImax had a similar correlation with LVEDP ≥ 15 mm Hg (r = 0.41 [p <0.001] vs r = 0.42 [p <0.001]), LAVmin ≥ 18 mls/m² had a greater sensitivity for LVEDP ≥ 15 mm Hg than LAVImax ≥ 34 mls/m² (sensitivity 59.4% vs 34.4%). In conclusion, utilizing thresholds of ≥18 and ≥34 mls/m², respectively, LAVImin was a better predictor of survival than LAVImax, the pathophysiologic basis of which relates to a better sensitivity for elevated left ventricular filling pressures with LAVImin at these thresholds. There may be incremental clinical value in measuring LAVImin alongside LAVImax.

Impact of diabetes mellitus on the contractile properties of the left and right atrial myofilaments

OBJECTIVES

The incidence of diabetes mellitus in patients with ischaemic cardiomyopathy is increasing. To evaluate the impact of diabetes mellitus on contractility, we examined the calcium-induced force in left and right atrial myofilaments of patients with and without diabetes.

METHODS

We included 149 patients (106 without diabetes, 43 with diabetes), scheduled for elective coronary artery bypass grafting from August 2016 to June 2017. The left and right atria were excised and prepared for skinned fibre measurements (pCa-force curve). The unit for the force measurements is Millinewton (mN). Comprehensive demographic data as well as echocardiographic findings of the patients were collected.

RESULTS

We observed a significant decrease of left atrial force values in patients with diabetes, averaged over all calcium concentrations (patients with diabetes 0.50 ± 0.19 mN vs 0.68 ± 0.23 mN in patients without diabetes, P = 0.002) as well as in right atrial fibres (patients with diabetes 0.35 ± 0.17 mN vs 0.47 ± 0.21 mN in patients without diabetes, P = 0.005). There was a significant influence of repeated measurements (of the calcium concentrations) on force in left atrial myofilaments (P < 0.001). There was also a significant impact of diabetes on the force values of the different calcium concentrations in left atrial myofilaments (P 0.002). In right atrial myofilaments we also found a significant influence of repeated measurements (of the calcium concentrations) on force (P < 0.001). Additionally the impact of diabetes on the force values was significant (P = 0.005).

CONCLUSIONS

We demonstrated that diabetes mellitus has a significantly negative impact on calcium-induced force development in left and right atrial myofilaments.

Atrioventricular mechanical coupling and major adverse cardiac events in female patients following acute ST elevation myocardial infarction

BACKGROUND

Sex-specific outcome data following myocardial infarction (MI) are inconclusive with some evidence suggesting association of female sex and increased major adverse cardiac events (MACE). Since mechanistic principles remain elusive, we aimed to quantify the underlying phenotype using cardiovascular magnetic resonance (CMR) quantitative deformation imaging and tissue characterisation.

METHODS

In total, 795 ST-elevation MI patients underwent post-interventional CMR imaging. Feature-tracking (CMR-FT) was performed in a blinded core-laboratory. Left ventricular function was quantified using ejection fraction (LVEF) and global longitudinal/circumferential/radial strains (GLS/GCS/GRS). Left atrial function was assessed by reservoir (εs), conduit (εe) and booster-pump strains (εa). Tissue characterisation included infarct size, microvascular obstruction and area at risk. Primary endpoint was the occurrence of MACE within 1 year.

RESULTS

Female sex was associated with increased MACE (HR 1.96, 95% CI 1.13-3.42, p = 0.017) but not independently of baseline confounders (p = 0.526) with women being older, more often diabetic and hypertensive (p < 0.001) and of higher Killip-class (p = 0.010). Tissue characterisation was similar between sexes. Women showed impaired atrial (εs p = 0.011, εe p < 0.001) but increased systolic ventricular mechanics (GLS p = 0.001, LVEF p = 0.048). While atrial and ventricular function predicted MACE in men only LV GLS and GCS were associated with MACE in women irrespective of confounders (GLS p = 0.036, GCS p = 0.04).

CONCLUSION

In men ventricular systolic contractility is impaired and volume assessments precisely stratify elevated risks. In contrast, women experience reduced atrial but increased ventricular systolic strain. This may reflect ventricular diastolic failure with systolic compensation, which is independently associated with MACE adding incremental value to sex-specific prognosis evaluation.

Left atrial volume quantification using coronary calcium score scan: Feasibility, reliability and reproducibility analysis of a standardized approach

BACKGROUND

Left atrial volume (LAV) is an independent prognosticator of cardiovascular events. We investigated whether LAV could be accurately and reliably measured using coronary calcium score (CAC) scan.

METHODS

We retrospectively selected consecutive patients that underwent coronary CT angiography (CCTA) and CAC scans. A standardized approach to calculate LAV on images was implemented. The measurements of the LAV on CAC scans and CCTA were performed one to three weeks apart in a random fashion by two readers blinded to the results of each other. The LAV measurements from CAC scan were compared to those from CCTA using correlation analysis. Inter-observer and intra-observer agreement of LAV measurement using CAC scan was evaluated.

RESULTS

Final analysis included one hundred subjects, mean age 52 ± 12 years, 48% male. There was a trend of a marginally larger, albeit not clinically significant, mean LAV calculated using CAC scan compared to that using CCTA: 74.3 vs. 71.0 mL: p < 0.001; for reader 1, and 71.7 vs. 71.2 mL p = 0.06 for reader 2, respectively. LAV using CAC scan and CCTA were highly correlated (R = 0.954, p < 0.001 for reader1 and R = 0.945, p < 0.001 for reader 2). There was high reproducibility within each reader with ICC of 0.951 and 0.989 for readers 1 and 2, respectively (p < 0.001). Finally, there was high inter-observer agreement as indicated by R of 0.97 and ICC of 0.96 (p < 0.001 for both).

CONCLUSIONS

Quantification of LAV from CAC scan using the proposed standardized approach is feasible, highly reliable and reproducible as compared to CCTA.

Prognostic Implications of the Left Atrial Volume Index in Patients with Progressive Mitral Stenosis

BACKGROUND

Limited data are available on the prognosis of progressive mitral stenosis (MS). We evaluated the factors associated with adverse events in patients with progressive MS.

METHODS

We retrospectively analyzed 259 consecutive patients with pure progressive MS with a mitral valve area (MVA) between 1.5 and 2.0 cm². The primary outcome measures were a composite endpoint of cardiac death, heart failure hospitalization, mitral valve surgery or percutaneous mitral valvuloplasty, and ischemic stroke.

RESULTS

The mean patient age was 62 ± 12 years, and the mean MVA was 1.71 ± 0.15 cm². Over a median follow-up duration of 52 months, a total of 41 patients (18.3%) experienced the composite endpoint. In multivariable Cox regression analysis, prior stroke (hazard ratio [HR], 4.54; 95% confidence interval [CI], 2.16–9.54; p < 0.001) and left atrial volume index (LAVI) of > 50 mL/m² (HR, 4.45; 95% CI, 1.31–15.31; p = 0.017) were identified as independent predictors of the composite endpoint, even after adjusting for age and sex. Patients with a LAVI ≤ 50 mL/m² demonstrated favorable event-free survival compared with those with a LAVI > 50 mL/m² in either the overall population (p < 0.001) or asymptomatic patients (p = 0.002). Atrial fibrillation (AF), left ventricular mass index (LVMI), MVA, and mean diastolic pressure were factors independently associated with LAVI (all p < 0.05).

CONCLUSIONS

A deleterious impact of a high LAVI on outcome was observed in patients with progressive MS. The LAVI was mainly influenced by the presence of AF, the severity of MS, and LVMI in this population.

Effect of Erythropoietin Administration on Myocardial Viability and Coronary Microvascular Dysfunction in Anterior Acute Myocardial Infarction: Randomized Controlled Trial in the Japanese Population

Introduction

Cardioprotective effects of erythropoietin (EPO) on infarcted myocardium in acute myocardial infarction (AMI) patients have been inconclusive. This study aimed to assess the effect of EPO administration on coronary microvascular dysfunction (CMD) and myocardial viability in anterior AMI. We also evaluated the serial changes in CMD and cardiac remodeling in these patients.

Methods

Patients with a successful percutaneous coronary intervention (PCI) for the first anterior AMI were randomly assigned to two groups (EPO and control groups), and given single-dose intravenous administration of recombinant human EPO (12,000 IU) or saline after PCI. Delayed-enhanced cardiac magnetic resonance imaging was performed at 1 week after AMI to assess the average of transmural extent of infarction and infarct size. Coronary flow velocity reserve (CFVR) of the left anterior descending coronary artery was measured by Doppler echocardiography at 1 week, 1 month, and 8 months after AMI. All patients underwent clinical follow-up for the assessment of cardiac remodeling.

Results

Sixty-one patients (EPO 32, control 29) were eligible for analysis. EPO group (2.4 ± 1.2) had a tendency of smaller transmural extent of infarction than that of control group (2.9 ± 1.1; p = 0.063). CFVR-8 months improved significantly in EPO group (2.9 ± 0.6) compared to control group (2.6 ± 0.5; p = 0.04). Left atrial (LA) volume − 8 months was significantly lower in EPO group (47 ± 11) than those of control group (65 ± 20; p = 0.004).

Conclusions

A single medium dose of EPO could have a favorable effect on CMD and LA remodeling in the chronic phase of anterior AMI.

Trial Registration

The institutional ethics committee of Wakayama Medical University, identifier, 1125.

Electronic supplementary material

The online version of this article (10.1007/s40119-018-0122-1) contains supplementary material, which is available to authorized users.

Left atrial volume index: Can it provide additional prognostic information in ST-segment elevation myocardial infarction treated with primary percutaneous coronary intervention?

INTRODUCTION

We sought to assess the prognostic impact of left atrial (LA) size on long-term outcomes of ST-segment elevation myocardial infarction (STEMI).

METHODS

We studied 200 consecutive patients admitted to a single center between January 2010 and December 2014 with non-fatal STEMI treated with primary percutaneous coronary intervention (pPCI) who underwent a comprehensive echocardiographic examination at discharge. LA volume was estimated by the area-length method. The left atrium was classified as normal, mildly, moderately or severely enlarged by LA volume index (LAVI). The endpoints were defined as all-cause mortality, a cardiac composite endpoint (all-cause mortality, reinfarction, unplanned revascularization and hospitalization for heart failure) and a cardiovascular composite endpoint (cardiac endpoint plus atrial fibrillation and ischemic stroke) during follow-up.

RESULTS

In this STEMI population, 58% had normal LA size, 22.5% had mild LA enlargement, 10% had moderate LA enlargement and 9.5% had severe LA enlargement. During a median follow-up of 28 (IQR 21-38) months, 14 (7.0%) patients died, 53 (26.5%) had the cardiac and 58 (29%) the cardiovascular composite endpoints. There was a stepwise increase in the incidence of all-cause mortality (p=0.020) and both cardiac (p<0.001) and cardiovascular (p<0.001) endpoints with each increment of LAVI class. In multivariate analysis, severe LA enlargement by LAVI was an independent predictor of all-cause mortality (HR: 11.153; 95% CI: 1.924-64.642, p=0.007) and the cardiac (HR: 4.351; 95% CI: 1.919-9.862, p<0.001) and cardiovascular (HR: 4.351; 95% CI: 1.919-9.862, p<0.001) endpoints during follow-up.

CONCLUSIONS

This contemporary study confirms the prognostic effect of LA size at discharge, applying the most recent reference values in STEMI patients treated with pPCI.

Left atrial deformation analysis by speckle tracking echocardiography to predict exercise capacity after myocardial infarction

INTRODUCTION

Left atrial (LA) size and function are associated with outcome after myocardial infarction (MI). In this study we aimed to assess the impact of LA function as a predictor of exercise capacity through speckle tracking echocardiography.

METHODS

A total of 94 patients (mean age 54.8±11.0 years; 82% male) were enrolled one month after MI. Echocardiography was used to assess LA volumes and various indices of LA conduit, contraction and reservoir function. LA deformation was assessed by two-dimensional speckle tracking to calculate strain and strain rate at different phases of the cardiac cycle. Exercise capacity was assessed by oxygen uptake (VO₂) on cardiopulmonary exercise testing.

RESULTS

Increased LA volumes, especially LA volume before atrial contraction, were correlated with reduced peak VO₂ and reduced VO₂ at anaerobic threshold. Decreased peak VO₂ was associated with reduced LA conduit function (ρ=0.24; p=0.02), but not with LA booster function (ρ=-0.07; p=0.53). Lower peak atrial longitudinal strain was associated with worse exercise capacity (ρ=0.24; p=0.02).

CONCLUSIONS

After MI, increased LA volumes were markers of decreased functional capacity that was associated with decreased LA conduit function, but not with LA contractile function. In these patients, LA longitudinal strain analysis may be useful to predict reduced exercise capacity.

Clinical implication of LAVI over A' ratio in patients with acute coronary syndrome

Purpose

The ratio of the left atrial volume index (LAVI) and late diastolic mitral annular velocity (A') is a useful echocardiographic index for identifying advanced left ventricular (LV) diastolic dysfunction in patients with dyspnoea. We investigated the clinical implications and prognostic value of the aforementioned ratio (LAVI/A') in patients with ST elevation (STE) or non-STE (NSTE) acute coronary syndrome (ACS).

Methods

We studied 212 patients with ACS. All patients underwent electrocardiography, echocardiography and measurement of plasma B-type natriuretic peptide (BNP) level on admission. The study endpoints were hospitalisation and mortality because of heart failure (HF).

Results

There was a significant, moderate positive correlation between LAVI/A' and natural logarithm (Ln) BNP level among the participants (r=0.48, p<0.0001). During a mean follow-up of 17 months, eight patients died and nine patients were hospitalised because of HF. The receiver operating characteristics curve indicated that LAVI/A'≥3.0 predicted these events (log-rank, p=0.0021). A significant and moderate positive correlation existed between LAVI/A' and Ln BNP level in the NSTE-ACS group (n=128; r=0.58, p<0.0001). However, the correlation between LAVI/A' and Ln BNP level was weaker in the STE-ACS group (n=84; r=0.33, p=0.0017).

Conclusion

LAVI/A' was related to plasma BNP levels in patients with ACS, particularly in those with NSTE-ACS. This index was useful for predicting cardiac events in patients with ACS.

Relation between left atrial measurements and thromboembolic risk markers assessed by echocardiography in patients with nonvalvular atrial fibrillation: A cross-sectional study

Background

Left atrium (LA) dilatation has been associated with adverse cardiovascular outcomes in patients with sinus rhythm and atrial fibrillation (AF).

Aim of the study

We aimed to evaluate the accuracy of left atrial (LA) size to predict transesophageal echocardiographic (TEE) markers of increased thromboembolic risk left atrial appendage (LAA) thrombus, low LAA velocities and dense spontaneous echocardiographic contrast (SEC), and also to assess the best method to evaluate LA size.

Patients and methods

Cross-sectional study included 64 patients with nonvalvular AF undergoing transthoracic and transesophageal echocardiographic (TTE and TEE) evaluation. LA size was measured on TTE by several methods including the following: anteroposterior diameter (AP), LA area in four and two apical chamber views and volumes by ellipsoid, single plane (1P) and biplane area-length (2P) formulas. All these measures were indexed to the body surface area (BSA). Thromboembolic markers including LAA thrombus, low LAA velocities, dense SEC and LA abnormality (LA ABN) which means the presence of one or more of the previous three parameters were evaluated by TEE.

Results

There was statistically significant increase in indexed and non-indexed LA parameters in patients with LA ABN compared to patients without LA ABN. According to ROC curve, the study found that all indexed LA parameters were predictive for LAA thrombus with the highest AUC was indexed LA 1P area length volume (AUC 0.91, CI 95% 0.81-1.01, p < 0.000), for LAA low flow velocity were indexed and non-indexed LA AP diameters with the highest AUC was indexed LA AP diameter (AUC 0.89, CI 95% 0.80-0.98, p < 0.000), for LA dense SEC were indexed LA ellipsoid volume (AUC 0.78, CI 95% 0.66-0.96, p = 0.002) and indexed LA 1P area length volume (AUC 0.78, CI 95% 0.66-0.90, p = 0.002) and for LA ABN were all LA parameters with the highest AUC was indexed LA 1P area length volume (AUC 0.87, CI 95% 0.79-0.96, p < 0.000). On multivariate logistic regression analysis of TEE parameters, the study found that the most predictive LA measurement for LAA thrombus was indexed LA AP diameter with cutoff 3 cm/m² (OR 7.5, 95% CI 1.24-45.2, p = 0.02), for LAA low flow velocity was LA AP diameter with cutoff 6 cm (OR 17.6, 95% CI 3.23-95.84, p = 0.001), for LA dense SEC was indexed LA ellipsoid volume with cutoff 42 cm³/m² (OR 6.5, 95% CI 1.32-32.07, p = 0.02), and for LA ABN was indexed LA ellipsoid volume with cutoff 42 cm³/m² (OR 10.45, 95% CI 2.18-51.9, p = 0.008).

Conclusion

LA enlargement is suitable to predict thromboembolic markers in patients with non-valvular AF. The indexed and non-indexed LA AP diameter and indexed LA ellipsoid volume were the most accurate parameters for predicting thromboembolic markers.

Association of non-alcoholic steatohepatitis with subclinical myocardial dysfunction in non-cirrhotic patients

BACKGROUND & AIMS

Non-alcoholic fatty liver disease (NAFLD) is associated with increased cardiovascular risk. Among categories of NAFLD, hepatic fibrosis is most likely to affect mortality. Myocardial function and its energy metabolism are tightly linked, which might be altered by an insulin resistant condition such as NAFLD. We investigated whether hepatic steatosis and fibrosis were associated with myocardial dysfunction relative to myocardial glucose uptake.

METHODS

A total of 308 patients (190 without NAFLD, 118 with NAFLD) were studied in a tertiary care hospital. Myocardial glucose uptake was evaluated at fasted state using [¹⁸F]-fluorodeoxyglucose-positron emission tomography (¹⁸FDG-PET). Hepatic steatosis and fibrosis were assessed by transient liver elastography (Fibroscan®) with controlled attenuation parameter, which quantifies hepatic fat and by surrogate indices (fatty liver index and NAFLD fibrosis score). Cardiac structure and function were examined by echocardiogram.

RESULTS

Compared to those without NAFLD, patients with NAFLD had alterations in cardiac remodeling, manifested by increased left ventricular mass index, left ventricular end-diastolic diameter, and left atrial volume index (all p <0.05). Hepatic steatosis was significantly associated with left ventricular filling pressure (E/e' ratio), which reflects diastolic dysfunction (p for trend <0.05). Those without NAFLD were more likely to have higher myocardial glucose uptake compared to those with NAFLD. Significant hepatic fibrosis was also correlated with diastolic dysfunction and impaired myocardial glucose uptake. Using multivariable linear regression, E/e' ratio was independently associated with hepatic fibrosis (standardized β = 0.12 to 0.27; all p <0.05). Association between hepatic steatosis and E/e' ratio was also significant (standardized β = 0.10 to 0.15; all p <0.05 excluding the model adjusted for adiposity).

CONCLUSIONS

Hepatic steatosis and fibrosis are significantly associated with diastolic heart dysfunction. This association is linked with myocardial glucose uptake evaluated by ¹⁸FDG-PET.

LAY SUMMARY

Non-alcoholic fatty liver disease is associated with an increased risk of cardiovascular disease. More severe forms of non-alcoholic fatty liver disease, where hepatic fibrosis occurs, are linked to increased mortality. In this study, we have shown that hepatic steatosis and fibrosis are associated with subclinical myocardial dysfunction. This association is linked to altered myocardial glucose uptake.

Comparison between characteristics of severe and very severe aortic stenosis

OBJECTIVES

Patients with very severe aortic stenosis (AS) have extremely poor clinical outcomes even if they are asymptomatic compared to those with severe AS, but the clinical and echocardiographic characteristics of patients with very severe AS remain unclear.

METHODS

The Asian Valve Registry is a prospective, multicenter, multinational registry for the study and identification of the incidence, natural course, clinical outcomes, and prognostic factors for patients with significant AS at 9 centers in Asian countries. Severe AS was observed in 367 of 1066 patients with AS, and 212 were classified as very severe AS, defined as a peak aortic valve velocity ≥5.0 m/s or a mean aortic valve gradient ≥60 mm Hg.

RESULTS

The prevalence of NYHA functional class II-IV among patients with very severe AS was significantly higher than that among patients with severe AS (67.9% vs 51.5%, P < .001). As for echocardiographic parameters, it was noteworthy that left ventricular mass index (LVMI) and left atrial volume index (LAVI) for patients with very severe AS were significantly larger than those for patients with severe AS (LVMI: 145.1 ± 36.4 g/m² vs 119.2 ± 32.1 g/m² , P < .0001; LAVI: 56.1 ± 24.6 mL/m² vs 49.8 ± 22.6 mL/m² , P = .002). Moreover, multivariate logistic regression analysis showed that LVMI was the only independently associated with NYHA functional class II-IV in patients with very severe AS.

CONCLUSIONS

Our findings may well have clinical implications for better management of patients with AS and lead to better understanding of poor outcomes for patients with very severe AS.

Shortness of breath in clinical practice: A case for left atrial function and exercise stress testing for a comprehensive diastolic heart failure workup

The symptom cluster of shortness of breath (SOB) contributes significantly to the outpatient workload of cardiology services. The workup of these patients includes blood chemistry and biomarkers, imaging and functional testing of the heart and lungs. A diagnosis of diastolic heart failure is inferred through the exclusion of systolic abnormalities, a normal pulmonary function test and normal hemoglobin, coupled with diastolic abnormalities on echocardiography. Differentiating confounders such as obesity or deconditioning in a patient with diastolic abnormalities is difficult. While the most recent guidelines provide more avenues for diagnosis, such as incorporating the left atrial size, little emphasis is given to understanding left atrial function, which contributes to at least 25% of diastolic left ventricular filling; additionally, exercise stress testing to elicit symptoms and test the dynamics of diastolic parameters, especially when access to the "gold standard" invasive tests is lacking, presents clinical translational gaps. It is thus important in diastolic heart failure work up to understand left atrial mechanics and the role of exercise testing to build a comprehensive argument for the diagnosis of diastolic heart failure in a patient presenting with SOB.