Left atrial size is the major predictor of cardiac death and overall clinical outcome in patients with dilated cardiomyopathy: a long-term follow-up study

Predictive value of a comprehensive atrial assessment with cardiac magnetic resonance in non-ischemic cardiomyopathy: keep it simple

Cardiac magnetic resonance (CMR) can provide a multi-parametric evaluation of left atrial (LA) size and function. A complete CMR-based LA assessment might improve the risk stratification of patients with non-ischemic dilated cardiomyopathy (DCM). We performed a comprehensive CMR-based evaluation of LA size and function, in order to assess the prognostic impact of specific LA parameters in DCM. Secondary analysis of a prospective registry (UHSM-CMR study, NCT02326324) including 648 consecutive patients with DCM and CMR evaluation of LA area and LA length. Of these, 456 had complete LA assessment covering reservoir, conduit and booster pump function and including LA reservoir strain evaluated with feature tracking. The heart failure (HF) endpoint included HF hospitalizations, HF death and heart transplant. The arrhythmic endpoint included ventricular arrhythmias (VA) (sustained or treated by implantable defibrillator) and sudden death (SD). At median follow-up of 23 months, 34 patients reached the HF endpoint; in a multivariable model including NYHA class and LVEF, LA length had incremental predictive value. LA length ≥ 69 mm was the best cut-off to predict HF events (adjusted HR 2.3, p = 0.03). Among the 456 patients with comprehensive LA assessment, only LA length was independently associated with the HF endpoint after adjusting for LVEF and NYHA class. By contrast, no LA parameter independently predicted the arrhythmic risk. In DCM patients, LA length is an independent predictor of HF events, showing stronger association than other more complex parameters of LA function. No atrial parameter predicts the risk of VA and SD.

Association of atrial myopathy in mitral valve disease on safety outcomes in left atrial appendage closure

BACKGROUND

Patients undergoing left atrial appendage (LAA) occlusion (LAAO) are multi-morbid, including mitral valve disease (MVD) which is associated with anatomic changes of the left atrium (LA). This study aims to identify how atrial myopathy in MVD influences outcomes in LAAO.

METHODS

Atrial myopathy in MVD was defined as LA diameter > 45 mm (♀) and > 48 mm (♂) and existing MVD or history of surgical/interventional treatment. Patients were compared with controls from the prospective, multicentre LAArge registry of LAAO.

RESULTS

A total of 528 patients (52 MVD, 476 no-MVD) were included. The MVD group was significantly more likely to be older (78.2 years vs 75.9 years, p = 0.036) and female (59.6% vs 37.8%, p = 0.002). Altered LA anatomy was observed in MVD with significantly larger LA diameter (53 mm vs. 48 mm, p < 0.001) and LAA Ostia [at 135° 23.0 mm (20.5, 26.0) vs 20.0 mm (18.0, 23.0), p = 0.002]. Implant success was high with 96.2% and 97.9%, respectively, without differences in severe complications (7.7% vs 4.6%, p = 0.31). One-year mortality (17.8% vs 11.5%, p = 0.19) and a combined outcome of death, stroke, and systemic embolism (20.3% vs 12.4%, p = 0.13) were not different. Independent predictors of the combined outcome were peripheral artery disease (HR 2.41, 95% CI 1.46-3.98, p < 0.001) and chronic kidney disease (HR 3.46, 95% CI 2.02-5.93, p < 0.001) but not MVD and atrial myopathy.

CONCLUSION

Patients with MVD present with altered LA anatomy with increased LA and LAA diameter. However, procedural success and safety in LAAO are not compromised. One-year mortality is numerically higher in patients with MVD but driven by comorbidities.

A short P-wave duration is associated with incident heart failure in the elderly: a 15 years follow-up cohort study

BACKGROUND

Early identification of patients at risk of congestive heart failure (HF) may alter their poor prognosis. The aim was therefore to test whether simple electrocardiographic variables, the P-wave and PR-interval, could predict incident HF.

METHODS

The PIVUS (Prospective Investigation of the Vasculature in Uppsala Seniors) study (1016 individuals all aged 70 years, 50% women) was used to identify predictors of HF. Subjects with prevalent HF, QRS duration ≥ 130 ms, atrial tachyarrhythmias, implanted pacemaker/defibrillator, second- and third-degree atrioventricular block or delta waves at baseline were excluded. Cox proportional hazard analysis was used to relate the PR interval, P-wave duration (Pdur) and amplitude (Pamp), measured in lead V1, to incident HF. Adjustment was performed for gender, RR-interval, beta-blocking agents, systolic blood pressure, body mass index and smoking.

RESULTS

Out of 836 subjects at risk, 107 subjects were diagnosed with HF during a follow-up of 15 years. In the multivariate analysis, there was a strong U-shaped correlation between Pdur in lead V1 and incident HF (P = 0.0001) which was significant for a Pdur < 60 ms [HR = 2.75; 95% CI: 1.87-4.06, at Pdur 40 ms] but not for prolonged Pdur. There was no significant relationship between incident HF and the PR-interval or the Pamp. A Pdur < 60 ms improved discrimination by 3.7% when added to the traditional risk factors including sex, RR-interval, beta-blocking agents, systolic blood pressure, BMI and smoking (P = 0.048).

CONCLUSIONS

A short Pdur, an easily measured parameter on the ECG, may potentially be a useful marker of future HF, enabling its early detection and prevention, thus improving outcomes.

Left Atrial Geometry and Phasic Function Determined by Cardiac Magnetic Resonance Are Independent Predictors for Outcome in Non-Ischaemic Dilated Cardiomyopathy

Left atrial (LA) geometry and phasic functions are frequently impaired in non-ischaemic dilated cardiomyopathy (NIDCM). Cardiac magnetic resonance (CMR) can accurately measure LA function and geometry parameters. We sought to investigate their prognostic role in patients with NIDCM. We prospectively examined 212 patients with NIDCM (49 ± 14.2-year-old; 73.5% males) and 106 healthy controls. LA volumes, phasic functions, geometry, and fibrosis were determined using CMR. A composite outcome (cardiac death, ventricular tachyarrhythmias, heart failure hospitalization) was ascertained over a median of 26 months. LA phasic functions, sphericity index (LASI) and late gadolinium enhancement (LA-LGE) were considerably impaired in the diseased group (p < 0.001) and significantly correlated with impaired LV function parameters (p < 0.0001). After multivariate analysis, LA volumes, LASI, LA total strain (LA-ε_t) and LA-LGE were associated with increased risk of composite outcome (p < 0.001). Kaplan-Meier analysis showed significantly higher risk of composite endpoint for LA volumes (all p < 0.01), LASI > 0.725 (p < 0.003), and LA-ε_t < 30% (p < 0.0001). Stepwise Cox proportional-hazards models demonstrated a considerable incremental predictive value which resulted by adding LASI to LA-ε_t (Chi-square = 10.2, p < 0.001), and afterwards LA-LGE (Chi-Square = 15.8; p < 0.0001). NIDCM patients with defective LA volumes, LASI, LA-LGE and LA-ε_t had a higher risk for an outcome. LA-ε_t, LASI and LA-LGE provided independent incremental predictive value for outcome.

The prognostic value of P-wave dispersion and left atrial functions assessed with three-dimensional echocardiography in patients with cirrhosis

BACKGROUND

Cirrhotic cardiomyopathy (CCM) is a well-known entity. The aim of this study was to compare left atrial three-dimensional (3D) volume and P-wave dispersion (PWd) in patients with cirrhosis and a healthy population. The secondary purpose was to assess the left phasic volumes and reservoir functions with 3D echocardiography for the prediction of an increased risk of poor outcomes in patients with cirrhosis.

METHODS

The study included 50 patients with cirrhosis and 43 healthy control subjects without atrial fibrillation. All patients were assessed with two-dimensional (2D), 3D, and tissue Doppler transthoracic echocardiography. The PWd was calculated using a 12-lead surface electrocardiogram (ECG). Cirrhotic patients were followed up for 2.5 years for the evaluation of poor outcomes and the development of atrial fibrillation.

RESULTS

Patients with cirrhosis were observed to have significantly higher left atrial phasic volumes such as minimal left atrial volume (3D-LAVmin, P = 0.004) and indexed LAVmin (3D-LAVImin, P = 0.0001), and significantly decreased left atrial reservoir functions such as left atrial emptying volume (3D-LAEV, P = 0,001), left atrial ejection fraction (3D-LAEF, P = 0,001) on 3D echocardiography. PWd was determined to be significantly longer in the cirrhotic group compared with the control group (P = 0.003). In the 2.5-year follow-up period, poor outcomes occurred in 34 patients (22 patients died, six patients had liver transplantation, six patients developed atrial fibrillation/AHRE episodes). In Cox regression analysis, the MELD score (HR, 1.16 (1.06-1.26), P = 0.001) and 3D-LAVImin (HR, 0.95 (0.86-1.00), P = 0.040) were significantly associated with all-cause mortality. Cirrhotic patients with LAVImin of >15 ml/m2 were seen to have poor survival (long rank P = 0.033).

CONCLUSION

The results of this study showed that patients with cirrhosis had higher left atrial volume, longer PWd and worse diastolic functions compared with the control group. Higher disease severity scores were associated with left atrial function and volume. In addition, left atrial volume measured with 3DE was a strong predictor of future adverse events, and minimal left atrial volumes had a higher prognostic value than any other left atrial function indices.

Association of lung diffusion capacity with cardiac remodeling and risk of heart failure: The Framingham heart study

Background

Lung function abnormalities are ubiquitous in heart failure (HF). It is unclear, however, if abnormal lung diffusion capacity is associated with cardiac remodeling and antedates HF. We hypothesized that lower lung diffusion capacity for carbon monoxide (DLCO) is associated with worse left ventricular (LV) systolic and diastolic function cross-sectionally, and with higher risk of HF prospectively.

Methods

We evaluated 2423 Framingham Study participants (mean age 66 years, 55% women) free of HF who underwent routine echocardiography and pulmonary function tests. We used multivariable regression models to relate DLCO, forced vital capacity (FVC), and forced expiratory volume in 1 second (FEV1) to left ventricular ejection fraction (LVEF), left atrial (LA) emptying fraction (LAEF), E/e’, E/A, LV mass, and LA diameter (LAD). Multivariable-adjusted Cox proportional hazards regression was used to relate DLCO, FEV1, and FVC to incident HF.

Results

In multivariable-adjusted cross-sectional analyses, DLCO, FEV1, and FVC (dependent variables) were associated positively with LVEF (β_DLCO = 0.208, β_FEV1 = 0.021, and β_FVC = 0.025 per 5% increment in LVEF; p<0.005 for all), and LAEF (β_DLCO = 0.707, β_FEV1 = 0.058 and β_FVC = 0.058 per 5% increment in LAEF; p<0.002 for all). DLCO and FVC were inversely related to E/A (β_DLCO = -0.289, β_FVC = -0.047 per SD increment in E/A; p<0.001 for all). Additionally, DLCO, FEV1 and FVC were inversely related to HF risk (108 events, median follow-up 9.7 years; multivariable-adjusted hazard ratios per SD increment 0.90, 95% CI 0.86–0.95; 0.42, 95% CI 0.28–0.65, and 0.51, 95% CI 0.36–0.73, respectively). These results remained robust in analyses restricted to non-smokers.

Conclusions

Our large community-based observations are consistent with the concept that lower lung diffusion capacity and expiratory flow rates are associated with cardiac remodeling and may antedate HF. Additional studies are needed to confirm our findings and to evaluate the prognostic utility of pulmonary function testing for predicting HF.

The Impact of the Cox-Maze Technique on Freedom From Atrial Fibrillation

BACKGROUND

Atrial fibrillation (AF) is the most common arrhythmia observed with concomitant cardiac surgery. Surgical options include a cut-and-sew technique Maze (CAS) and a cryoablation/bipolar technique Maze (CB). There are limited data comparing the long-term outcomes of these 2 techniques.

METHODS

All patients who underwent either CAS or CB Maze between 2011 and 2018 were included in the study. Chi-square test and Fisher's exact test or Student's t test were used to compare differences between baseline characteristics. Kaplan-Meier survival curves were generated for each group. Cumulative incidence functions were generated for AF recurrence and Fine-Gray competing-risk regression was used to determine predictors for AF recurrence.

RESULTS

A total of 482 patients underwent open surgical ablation. Of those, 287 had CAS and 198 had CB. All procedures were concomitant with cardiac surgery. There was similar long-term mortality between the CAS and CB cohorts (22.3% vs 17.4%; log-rank P = .91). There was no difference in pacemaker implantation (11.1% vs 11.3%; P = .813) or long-term freedom from AF recurrence (73.3% vs 78.2%; P = .294). On Fine-Gray competing-risk regression, New York Heart Association functional class IV (hazard ratio [HR], 2.07; P = .03), concomitant aortic valve replacement (HR, 3.02; P = .01), and concomitant CABG + valve (HR, 2.36; P = .02) were significant independent predictors for AF recurrence; Maze type was not a predictor.

CONCLUSIONS

These data indicate no difference between the CAS vs CB with respect to freedom from long-term AF. Both techniques may be appropriate based on surgeon experience and patient characteristics.

Identification of Circular RNA-MicroRNA-Messenger RNA Regulatory Network in Atrial Fibrillation by Integrated Analysis

BACKGROUND

Circular RNA (circRNA) is a noncoding RNA that forms a closed-loop structure, and its abnormal expression may cause disease. We aimed to find potential network for circRNA-related competitive endogenous RNA (ceRNA) in atrial fibrillation (AF).

METHODS

The circRNA, miRNA, and mRNA expression profiles in the heart tissue from AF patients were retrieved from the Gene Expression Omnibus database and analyzed comprehensively. Differentially expressed circRNAs (DEcircRNAs), differentially expressed miRNAs (DEmiRNAs), and differentially expressed mRNAs (DEmRNAs) were identified, followed by the establishment of DEcircRNA-DEmiRNA-DEmRNA regulatory network. Functional annotation analysis of host gene of DEcircRNAs and DEmRNAs in ceRNA regulatory network was performed. In vitro experiment and electronic validation were used to validate the expression of DEcircRNAs, DEmiRNAs, and DEmRNAs.

RESULTS

A total of 1611 DEcircRNAs, 51 DEmiRNAs, and 1250 DEmRNAs were identified in AF. The DEcircRNA-DEmiRNA-DEmRNA network contained 62 circRNAs, 14 miRNAs, and 728 mRNAs. Among which, two ceRNA regulatory pairs of hsa-circRNA-100053-hsa-miR-455-5p-TRPV1 and hsa-circRNA-005843-hsa-miR-188-5p-SPON1 were identified. In addition, six miRNA-mRNA regulatory pairs including hsa-miR-34c-5p-INMT, hsa-miR-1253-DDIT4L, hsa-miR-508-5p-SMOC2, hsa-miR-943-ACTA1, hsa-miR-338-3p-WIPI1, and hsa-miR-199a-3p-RAP1GAP2 were also obtained. MTOR was a significantly enriched signaling pathway of host gene of DEcircRNAs. In addition, arrhythmogenic right ventricular cardiomyopathy, dilated cardiomyopathy, and hypertrophic cardiomyopathy were remarkably enriched signaling pathways of DEmRNAs in DEcircRNA-DEmiRNA-DEmRNA regulatory network. The expression validation of hsa-circRNA-402565, hsa-miR-34c-5p, hsa-miR-188-5p, SPON1, DDIT4L, SMOC2, and WIPI1 was consistent with the integrated analysis.

CONCLUSION

We speculated that hsa-circRNA-100053-hsa-miR-455-5p-TRPV1 and hsa-circRNA-005843-hsa-miR-188-5p-SPON1 interaction pairs may be involved in AF.

Assessment of left atrial volume and function in patients with Sjögren's syndrome using three-dimensional echocardiography

OBJECTIVE

We used real time, three-dimensional transthoracic echocardiography (3DTTE) to evaluate left atrial (LA) volume and mechanical function in patients with primary Sjögren's syndrome (SS).

METHODS

We prospectively included 42 consecutive patients with primary SS and 42 controls who were similar in terms of basal characteristics. 3DTTE was used to assess LA function.

RESULTS

Maximum LA volume, minimum LA volume, pre-atrial contraction LA volume, LA Active Stroke Volume (ASV), LA Total Stroke Volume (TSV), maximal left atrial volume index (LAVImax), Left atrial pre-contraction volume index, and Left atrial minimum volume index, ASV index, and TSV index were significantly higher in the SS group, and the LA Total Emptying Fraction, LA Expansion Index, and LA Passive Emptying Fraction were significantly lower. Although the active emptying fraction was higher in the SS group, the difference was not statistically significant. LAVImax was positive correlated with disease duration (r = .753).

CONCLUSION

Left atrial function is impaired in SS patients and serves as an early marker of subclinical cardiac involvement.

Relationships among pulmonary capillary wedge pressure, dry weight and natriuretic peptide in patients undergoing hemodialysis: a three-dimensional speckle tracking echocardiography study

BACKGROUND

Although the evaluation of fluid status in hemodialysis (HD) patients is useful, relationship among pulmonary capillary wedge pressure (PCWP), dry body weight (DW) and natriuretic peptide has not been elucidated. In addition, there has been no objective marker for instantaneously monitoring hemodynamic improvement in response to HD. We previously reported that PCWP and time constant of left ventricular pressure decline (Tau) can be noninvasively estimated (ePCWP and eTau) by speckle tracking echocardiography (STE). The aim of this study was to elucidate the relationship among ePCWP, eTau, DW and natriuretic peptide in patients undergoing HD.

METHODS

We measured ePCWP and body weight (BW) by STE in 81 patients and ANP and BNP by blood examination in 31 patients just before and after HD during sinus rhythm.

RESULTS

The ePCWP decreased after HD, and this was associated with reductions in ln ANP, eTau and BW (r = 0.523, 0.271 and 0.814, respectively, p < 0.05). The % change in ePCWP was not correlated with the % change in ln BNP (p = 0.47). The change in ePCWP had a stronger correlation with the % change in BW than the change in any other parameters.

CONCLUSIONS

The ePCWP is more sensitive to estimate the change in BW during HD than any other parameters such as ANP and BNP. These results indicated that a substantial amount of excess fluid can be assessed real-time by STE using ePCWP.

Characterisation of the developing heart in a pressure overloaded model utilising RNA sequencing to direct functional analysis

Cardiogenesis is influenced by both environmental and genetic factors, with blood flow playing a critical role in cardiac remodelling. Perturbation of any of these factors could lead to abnormal heart development and hence the formation of congenital heart defects. Although abnormal blood flow has been associated with a number of heart defects, the effects of abnormal pressure load on the developing heart gene expression profile have to date not clearly been defined. To determine the heart transcriptional response to haemodynamic alteration during development, outflow tract (OFT) banding was employed in the chick embryo at Hamburger and Hamilton stage (HH) 21. Stereological and expression studies, including the use of global expression analysis by RNA sequencing with an optimised procedure for effective globin depletion, were subsequently performed on HH29 OFT-banded hearts and compared with sham control hearts, with further targeted expression investigations at HH35. The OFT-banded hearts were found to have an abnormal morphology with a rounded appearance and left-sided dilation in comparison with controls. Internal analysis showed they typically had a ventricular septal defect and reductions in the myocardial wall and trabeculae, with an increase in the lumen on the left side of the heart. There was also a significant reduction in apoptosis. The differentially expressed genes were found to be predominately involved in contraction, metabolism, apoptosis and neural development, suggesting a cardioprotective mechanism had been induced. Therefore, altered haemodynamics during development leads to left-sided dilation and differential expression of genes that may be associated with stress and maintaining cardiac output.

Comparison of Left Atrial Measurements Using 2- and 3-Dimensional Transesophageal Echocardiography

OBJECTIVES

To assess the correlation between left atrial measurements using 2- and 3-dimensional transesophageal echocardiography.

DESIGN

Prospective, observational study.

SETTING

Single, tertiary care, academic medical center.

PARTICIPANTS

The study comprised 63 consecutive patients undergoing cardiac surgery with cardiopulmonary bypass and intraoperative transesophageal echocardiography.

INTERVENTIONS

In addition to the standard comprehensive intraoperative transesophageal examination, study images were obtained by designated anesthesiologists from the study team.

MEASUREMENTS AND MAIN RESULTS

The 2-dimensional transesophageal echocardiography views included 4-chamber, 2-chamber, aortic valve short axis, and aortic valve long axis. For the 3-dimensional images, full-volume (90 × 90) data sets were acquired from 4-chamber and aortic valve short-axis views over 4 beats with apnea. Left atrial height, mediolateral length, anteroposterior length, and area were measured in 2- and 3-dimensional images. Left atrial length in the short- and long-axis views of the aortic valve also were measured in 2- and 3-dimensional images. Results indicate that for all patients in this study, the 2- and 3-dimensional measurements correlate well and the 2 observers were in agreement with each other.

CONCLUSIONS

Two- and 3-dimensional measurements of the left atrium correlated well. Measurements made using 3-dimensional transesophageal echocardiography were subject to similar limitations as those made using 2-dimensional echocardiography. The benefits of 3-dimensional transesophageal echocardiography and multiplanar reconstruction could be expanded by improvements in ultrasound technology and software.

Left ventricular extracellular volume fraction and atrioventricular interaction in hypertension

OBJECTIVES

Left atrial enlargement (LAE) predicts cardiovascular morbidity and mortality. Impaired LA function also confers poor prognosis. This study aimed to determine whether left ventricular (LV) interstitial fibrosis is associated with LAE and LA impairment in systemic hypertension.

METHODS

Following informed written consent, a prospective observational study of 86 hypertensive patients (49 ± 15 years, 53% male, office SBP 168 ± 30 mmHg, office DBP 97 ± 4 mmHg) and 20 normotensive controls (48 ± 13 years, 55% male, office SBP 130 ± 13 mmHg, office DBP 80 ± 11 mmHg) at 1.5-T cardiovascular magnetic resonance was conducted. Extracellular volume fraction (ECV) was calculated by T1-mapping. LA volume (LAV) was measured with biplane area-length method. LA reservoir, conduit and pump function were calculated with the phasic volumetric method.

RESULTS

Indexed LAV correlated with indexed LV mass (R = 0.376, p < 0.0001) and ECV (R = 0.359, p = 0.001). However, ECV was the strongest significant predictor of LAE in multivariate regression analysis (odds ratio [95th confidence interval] 1.24 [1.04-1.48], p = 0.017). Indexed myocardial interstitial volume was associated with significant reductions in LA reservoir (R = -0.437, p < 0.0001) and conduit (R = -0.316, p = 0.003) but not pump (R = -0.167, p = 0.125) function. Multiple linear regression, correcting for age, gender, BMI, BP and diabetes, showed an independent decrease of 3.5% LA total emptying fraction for each 10 ml/m² increase in myocardial interstitial volume (standard β coefficient -3.54, p = 0.002).

CONCLUSIONS

LV extracellular expansion is associated with LAE and impaired LA reservoir and conduit function. Future studies should identify if targeting diffuse LV fibrosis is beneficial in reverse remodelling of LA structural and functional pathological abnormalities in hypertension.

KEY POINTS

• Left atrial enlargement (LAE) and impairment are markers of adverse prognosis in systemic hypertension but their pathophysiology is poorly understood. • Left ventricular extracellular volume fraction was the strongest independent multivariate predictor of LAE and was associated with impaired left atrial reservoir and conduit function. • LV interstitial expansion may play a central role in the pathophysiology of adverse atrioventricular interaction in systemic hypertension.

Assessment of left atrial function in patients with type 2 diabetes mellitus with a disease duration of six months

INTRODUCTION

Changes in left atrial (LA) size and function are associated with adverse clinical events. Recently, duration of diabetes mellitus (DM2) has been found to be positively associated with increased LA volume and impaired LA function. This study was performed, using two-dimensional echocardiograpy, to evaluate the changes in LA volume and function in patients with DM2 with a disease duration of six months, and to assess the parameters that affect LA volume and function.

METHODS

Fifty-six patients (28 male, age: 52.6 ± 6.5 years) with DM2 and 56 controls (24 male; age: 50.1 ± 7.0 years) were enrolled in the study. Each subject underwent conventional two-dimensional echocardiography to assess LA volume (indexed maximal LA volume: Vmax, pre-atrial contraction volume: Volp, minimal LA volume: Vmin) and LA function [passive emptying volume - passive emptying fraction (PEV - PEF), active emptying volume - active emptying fraction (AEV - AEF), total emptying volume - total emptying fraction (TEV - TEF) ].

RESULTS

LA diameter, indexed Vmax, Volp, Vmin, AEV and TEV were found to be significantly higher in the DM2 group compared with the controls (p < 0.05). Indexed Vmax, Volp and Vmin were significantly correlated with HbA1c level, body mass index (BMI), high-sensitivity C-reactive protein and uric acid levels, mitral A wave, E/E' ratio and A' wave. According to multivariate analysis, age and BMI had a statistically significant effect on LA volume.

CONCLUSION

Impaired LA function may be present in patients with newly diagnosed DM2. BMI and increasing age caused LA enlargement and LA volumes that were independent of the effects of hypertension and DM2.

Left atrium in cardiac resynchronization therapy: Active participant or innocent bystander

Background

Cardiac resynchronization therapy (CRT) is an established treatment for patients with advanced heart failure that results in improvement of left ventricle (LV) systolic function and LV reverse remodeling. This may have a positive effect on the size and the function of the left atrium (LA). We assessed the LA function, dimensions, and volumes before and after CRT implantation.

Methods

A total of 37 patients with mean age of 55.3 ± 9.64 years including 11 (29.7%) females, having symptomatic heart failure [ejection fraction (EF) <35%, left bundle branch block >120 ms, with New York Heart Association III or ambulatory class IV] were enrolled, and underwent CRT implantation. M-mode, two-dimensional (2D) echocardiography, tissue Doppler imaging, and 2D strain (ɛ) imaging were done assessing LV volumes, ejection fraction, and diastolic function, LA diameter, area, maximal and minimal volumes, LA EF, and longitudinal strain (ɛ). Patients were reassessed after 3 months. A reduction in LV end-systolic volume of ≥10% was defined as volumetric responders to CRT. Patients with decompensated New York Heart Association class IV, sustained atrial arrhythmias, rheumatic or congenital heart diseases, nonleft bundle branch block, and those who were poorly echogenic, were excluded.

Results

Twenty-four (64.8%) patients were volumetric responders (group A). Both groups were matched regarding demographic, clinical, electrocardiographic, and echocardiographic criteria apart from the LA dimension and volumes which were significantly lower in the responders group prior to CRT. At the end of the follow-up, only the responders group had further significant reduction in LA diameter (41.6 ± 1.67 vs. 43.88 ± 1.82 mm, p < 0.01), maximal volume (62.2 ± 18.3 vs. 73.04 ± 21.78 ml, p < 0.01), minimal volume (32.6 ± 12.3 vs. 41.8 ± 13.97, p < 0.01), together with a significant increase in LA EF (48.3 ± 11.3 vs. 41.99 ± 13.9, p < 0.01), positive longitudinal strain (16.59% ± 5.89 vs. 12.45% ± 6.12, p < 0.01), and negative longitudinal strain (−3.3 ± 1.9 vs. −1.62 ± 1.2, p < 0.01) compared to baseline readings, a finding that was not present in the nonresponders group. In addition, atrial fibrillation was significantly higher in the nonresponders group. Baseline LA diameter and volumes were found to be independent predictors of response to CRT by multivariate analysis.

Conclusions

CRT induces LA anatomic, electrical, and structural reverse remodeling that could be assessed by conventional 2D echocardiography and 2D (ɛ) strain imaging. LA dimension and volumes were independent predictors of response to CRT and can help in selection of candidates for it.

Left atrial volume and function in patients with cardiac syndrome X assessed by real time three-dimensional echocardiography

OBJECTIVE

The aim of this study was to evaluate left atrial (LA) volume and function using real time three-dimensional echocardiography (RT3DE) in patients with cardiac syndrome X (CSX).

METHODS

Fifty patients with CSX (28 females; mean age 50.9±10.9 years) and 50 age- and gender-matched healthy controls (30 females; mean age 52.3±9.8 years) who had negative treadmill exercise test and normal coronary arteries on invasive coronary angiography were included in the study. Comprehensive two-dimensional (2D), pulsed and tissue Doppler, speckle tracking echocardiography, and RT3DE for the assessment of LA dynamics were performed in all study participants.

RESULTS

Cardiac syndrome X and control groups have similar clinical characteristics regarding age, sex, body mass index, hypertension, diabetes, and smoking habit. 2D echocardiographic parameters were also similar between groups. Pulsed- and tissue Doppler parameters, IVRT, A, and A_m values, were higher in CSX group, while E_m , E/A, and E_m /A_m ratios were higher in the control group reflecting mild diastolic dysfunction. Regarding RT3DE parameters, LA maximum volume, minimum volume, volume before atrial contraction, LA maximum volume index, total and active stroke volumes were found to be increased in CSX patients. However, LA total stroke fraction, passive stroke volume, passive stroke fraction, peak systolic, and diastolic longitudinal strains were found to be lower in CSX patients.

CONCLUSION

The main finding of this study was that CSX patients had altered LA booster pump, reservoir, and conduit functions. This finding may have clinical implications for early detection of abnormal LA dynamics in CSX patients.

Assessment of left atrial volume and function by real time three-dimensional echocardiography in obese patients

OBJECTIVE

To evaluate left atrial (LA) volume and functions in obese subjects using real time three-dimensional echocardiography (RT3DE) and also the relationship between LA mechanical functions and N-terminal pro-atrial natriuretic peptide (NT-proANP).

METHODS

This study included 40 obese (26 females and 14 males, mean age 51.9 years) and 40 normal weight subjects (23 females and 16 males, mean age 53.5 years) with normal coronary angiograms. All the study participants underwent RT3DE to assess LA volume and mechanical function. Plasma NT-proANP was determined by ELISA method.

RESULTS

There was no significant difference between groups in left ventricular (LV) diameters and ejection fraction, which reflect LV systolic function. However, transmitral deceleration time, isovolumetric relaxation time, and peak late diastolic tissue Doppler velocity values, which reflect LV diastolic function, were found to be significantly higher in obese subjects when compared with controls. LA maximum volume (LAVmax), LAVmax index (LAVI), LA minimal volume (LAVmin), before atrial contraction volume (LAVpreA), LA active emptying volume, LA total emptying volume, and LA active emptying fraction, which reflect LA reservoir and pump functions, were also higher in obese subjects when compared with controls. LA passive emptying fraction was significantly lower in obese subjects than in controls. NT-proANP levels were similar between groups. There were positive correlations between NT-proANP level and LAVI, LAVmax, LAVmin, LAVpreA, and LA total and active emptying volumes.

CONCLUSIONS

Left atrial mechanical functions and volumes are impaired in obese subjects. These findings may be regarded as early markers of subclinical cardiac failure in obese subjects who have not yet exhibited any clinical evidence of cardiovascular disease.

Electrocardiographic detection of hypertensive left atrial enlargement in the presence of obesity: re-calibration against cardiac magnetic resonance

Left atrial enlargement (LAE) has adverse prognostic implications in hypertension. We sought to determine the accuracy of five electrocardiogram (ECG) criteria for LAE in hypertension relative to cardiac magnetic resonance (CMR) gold standard and investigate the effect of concomitant obesity. One hundred and thirty consecutive patients (age: 51.4±15.1 years, 47% male, 51% obese, systolic blood pressure (BP): 171±29 mm Hg, diastolic BP: 97±15 mm Hg) referred for CMR (1.5 T) from a tertiary hypertension clinic were included. Patients with concomitant cardiac pathology were excluded. ECGs were assessed blindly for the following: (1) P-wave >110 ms, (2) P-mitrale, (3) P-wave axis <30°, (4) area of negative P-terminal force in V1 >40 ms.mm and (5) positive P-terminal force in augmented vector left (aVL) >0.5 mm. Left atrial volume ≥55 ml m^-2, measured blindly by CMR, was defined as LAE. Sensitivity, specificity, positive predictive value, negative predictive value, accuracy and area under the receiver operator curve were calculated. The prevalence of LAE by CMR was 26%. All the individual ECG LAE criteria were more specific than sensitive, with specificities ranging from 70% (P-axis <30^o) to 99% (P-mitrale). Obesity attenuated the specificity of most of the individual ECG LAE criteria. Obesity correlated with significant lower specificity (48% vs 65%, P<0.05) and a trend towards lower sensitivity (59 vs 43%, P=0.119) when ≥1 ECG LAE criteria were present. Individual ECG criteria of LAE in hypertension are specific, but not sensitive, at identifying LAE. The ECG should not be used to excluded LAE in hypertension, particularly in obese subjects.

Evaluation of left atrial mechanical function and atrial conduction abnormalities in Maras powder (smokeless tobacco) users and smokers

Objective

In Turkey, a type of smokeless tobacco called Maras powder (MP) is widely used in the south-eastern region. Smokeless tobacco is found in preparations for chewing and for absorption by the nasal and oral mucosae. The purpose of this study was to investigate whether MP damages intra- and inter-atrial conduction delay and left atrial (LA) mechanical function as much as cigarette smoking.

Method

A total of 150 chronic MP users (50 males, 32.5 ± 5.4 years), smokers (50 males, 32.1 ± 6.0 years) and controls (50 males, 30.1 ± 5.8 years) were included in the study. LA volumes were measured echocardiographically according to the biplane area–length method. Atrial electromechanical coupling was measured with tissue Doppler imaging and LA mechanical function parameters were calculated.

Results

The LA passive emptying fraction was significantly decreased and LA active emptying volume (LAAEV) was significantly increased in the MP group (p = 0.012 and p = 0.024, respectively), and the LA active emptying fraction (LAAEF) was significantly increased in the smokers (p = 0.003). There was a positive correlation between the amount of MP used and smoking (pack years) with LAAEV and LAAEF (r = 0.26, p = 0.009 and r = 0.25, p = 0.013, respectively). Lateral atrial electromechanical intervals (PA) were significantly higher in MP users, and the septal mitral PA was statistically higher in the smokers (p = 0.05 and p = 0.04, respectively).

Conclusion

We suggest that atrial electromechanical coupling intervals were prolonged and LA mechanical function was impaired in MP users and smokers, but there was no significant difference between the MP users and smokers. These findings may be markers of subclinical cardiac involvement and tendency for atrial fibrillation.

The mitral annular displacement by two-dimensional speckle tracking: a new tool in evaluating the left atrial function

BACKGROUND

The methods used to characterize the volume change and the deformation of the left atrium are highly dependent on technical factors and difficult to use in a clinical environment. The aim of this study was to demonstrate that mitral annular displacement by speckle tracking can be an alternative method to studying the longitudinal left atrial function.

METHODS

Ninety study participants (54% men), with a mean age of 53(±15) years, underwent a complete echocardiographic examination, comprising two-dimensional, three-dimensional and tissue Doppler imaging (TDI). They were divided into normal individuals (35) and patients having an abnormal echocardiography (55).

RESULTS

There was a very strong correlation between three-dimensional volumetric function and mitral annular displacement, both for the reservoir (r = 0.78; P < 0.0001) and contractile (r = 0.76; P < 0.0001) functions. The correlation with the longitudinal strain displayed an r = 0.87, P > 0.0001 for the reservoir and r = 0.81, P < 0.0001 for the contractile function. The systolic speed in pulsed TDI and the systolic displacement had an r = 0.83, P < 0.0001. Mitral annular displacement was a very good discriminator for normal versus abnormal participants [area under the curve (AUC) for reservoir = 0.872 and for contractile = 0.843; P < 0.0001], performing less well than three-dimensional (AUC reservoir = 0.892 and contractile = 0.915; P < 0.0001) or deformation (AUC = 0.921 and 0.903 respectively; P < 0.0001), but better than pulsed TDI (AUC = 0.807; P < 0.0001). The percentage error was ±15% for interobserver and ±12% for intraobserver variability. The time taken for displacement analysis was 9 ± 3 s for an experienced cardiologist and 12 ± 4 s for a beginner.

CONCLUSION

Mitral annular displacement by speckle tracking is a reliable and fast method to evaluate left atrial function. Given the strength of the correlations with strain parameters, it could be used as a surrogate measure of the deformation of left atrium.

Recommendations for cardiac chamber quantification by echocardiography in adults: an update from the American Society of Echocardiography and the European Association of Cardiovascular Imaging

The rapid technological developments of the past decade and the changes in echocardiographic practice brought about by these developments have resulted in the need for updated recommendations to the previously published guidelines for cardiac chamber quantification, which was the goal of the joint writing group assembled by the American Society of Echocardiography and the European Association of Cardiovascular Imaging. This document provides updated normal values for all four cardiac chambers, including three-dimensional echocardiography and myocardial deformation, when possible, on the basis of considerably larger numbers of normal subjects, compiled from multiple databases. In addition, this document attempts to eliminate several minor discrepancies that existed between previously published guidelines.

New insights into symptomatic or silent atrial fibrillation complicating acute myocardial infarction

Atrial fibrillation (AF) is the most frequent heart rhythm disorder in the general population and contributes not only to a major deterioration in quality of life but also to an increase in cardiovascular morbimortality. The onset of AF in the acute phase of myocardial infarction (MI) is a major event that can jeopardize the prognosis of patients in the short-, medium- and long-term, and is a powerful predictor of a poor prognosis after MI. The suspected mechanism underlying the excess mortality is the drop in coronary flow linked to the acceleration and arrhythmic nature of the left ventricular contractions, which reduce the left ventricular ejection fraction. The principal causes of AF-associated death after MI are linked to heart failure. Moreover, the excess risk of death in these heart failure patients has also been associated with the onset of sudden death. Whatever its form, AF has a major negative effect on patient prognosis. In recent studies, symptomatic AF was associated with inhospital mortality of 17.8%, to which can be added mortality at 1year of 18.8%. Surprisingly, silent AF also has a negative effect on the prognosis, as it is associated with an inhospital mortality rate of 10.4%, which remains high at 5.7% at 1year. Moreover, both forms of AF are independent predictors of mortality beyond traditional risk factors. The frequency and seriousness of silent AF in the short- and long-term, which were until recently rarely studied, raises the question of systematically screening for it in the acute phase of MI. Consequently, the use of continuous ECG monitoring could be a simple, effective and inexpensive solution to improve screening for AF, even though studies are still necessary to validate this strategy. Finally, complementary studies also effect of oxidative stress and endothelial dysfunction, which seem to play a major role in triggering this rhythm disorder.

Recommendations for cardiac chamber quantification by echocardiography in adults: an update from the American Society of Echocardiography and the European Association of Cardiovascular Imaging

The rapid technological developments of the past decade and the changes in echocardiographic practice brought about by these developments have resulted in the need for updated recommendations to the previously published guidelines for cardiac chamber quantification, which was the goal of the joint writing group assembled by the American Society of Echocardiography and the European Association of Cardiovascular Imaging. This document provides updated normal values for all four cardiac chambers, including three-dimensional echocardiography and myocardial deformation, when possible, on the basis of considerably larger numbers of normal subjects, compiled from multiple databases. In addition, this document attempts to eliminate several minor discrepancies that existed between previously published guidelines.

The Role of Magnetic Resonance Imaging and Cardiac Computed Tomography in the Assessment of Left Atrial Anatomy, Size, and Function

In the last decade, there has been increasing evidence that comprehensive evaluation of the left atrium is of utmost importance. Numerous studies have clearly demonstrated the prognostic value of left atrial volume for long-term outcome. Furthermore, advances in catheter ablation procedures used for the treatment of drug-refractory atrial fibrillation require the need for detailed knowledge of left atrial and pulmonary venous morphology as well of atrial wall characteristics. This review article discusses the role of cardiac magnetic resonance and computed tomography in assessment of left atrial size, its normal and abnormal morphology, and function. Special interest is paid to the utility of these rapidly involving noninvasive imaging methods before and after atrial fibrillation ablation.

Left atrial volume assessment in atrial fibrillation using multimodality imaging: a comparison of echocardiography, invasive three-dimensional CARTO and cardiac magnetic resonance imaging

Left atrial size in atrial fibrillation is a strong predictor of successful ablation and cardiovascular events. Cardiac magnetic resonance multislice method (CMR-MSM) is the current gold standard for left atrial volume (LAV) assessment but is time consuming. We investigated whether LAV with more rapid area-length method by echocardiography (Echo-AL) or cardiac magnetic resonance (CMR-AL) and invasive measurement by 3D-CARTO mapping during ablation correlate with the CMR-MSM. We studied 250 consecutive patients prior to atrial fibrillation ablation. CMR images were acquired on 3T scanner to measure LAV by MSM and biplane area-length method. Standard echocardiography views were used to calculate LAV by biplane area-length method. LAV during ablation was measured by 3D-CARTO mapping. LAV was compared using intra-class correlation (ICC), Pearson's correlation and Bland-Altman plots. CMR-MSM was used as the reference standard. Mean LAV using CMR-MSM was 112.7 ± 36.7 ml. CMR-AL method overestimated LAV by 13.3 ± 21.8 ml (11.2%, p < 0.005) whereas 3D-CARTO and Echo-AL underestimated LAV by 8.3 ± 22.6 and 24.0 ± 27.6 ml respectively (8.7% and 20.0% respectively, p < 0.005). There was no significant difference between paroxysmal and persistent atrial fibrillation. CMR-AL and 3D-CARTO correlated and agreed well with CMR-MSM (r = 0.87 and 0.74, ICC = 0.80 and 0.77 respectively). However, Echo-AL had poor correlation and agreement with CMR-MSM (r = 0.66 and ICC = 0.48). Bland-Altman plots confirmed these findings. CMR-AL method may be used as an alternative to CMR-MSM, as it is non-invasive, rapid, and correlates well with CMR-MSM. LAV by different modalities should not be used interchangeably.

Left atrium by echocardiography in clinical practice: from conventional methods to new echocardiographic techniques

Although often referred to as “the forgotten chamber”, compared with left ventricle (LV), especially in the past years, the left atrium (LA) plays a critical role in the clinical expression and prognosis of patients with heart and cerebrovascular disease, as demonstrated by several studies. Echocardiographers initially focused on early detection of atrial geometrical abnormalities through monodimensional atrial diameter quantification and then bidimensional (2D) areas and volume estimation. Now, together with conventional echocardiographic parameters, new echocardiographic techniques, such as strain Doppler, 2D speckle tracking and three-dimensional (3D) echocardiography, allow assessing early LA dysfunction and they all play a fundamental role to detect early functional remodelling before anatomical alterations occur. LA dysfunction and its important prognostic implications may be detected sooner by LA strain than by volumetric measurements.

Prognostic role of echocardiographic and hematologic parameters in heart failure patients complicated with incidental pleural effusion diagnosed during echocardiographic evaluation

We aimed to determine long-term prognostic role of echocardiographic and hematologic parameters in heart failure patients complicated with incidental pleural effusion (PE) diagnosed during echocardiographic evaluation. The study was performed by evaluating patient records in which PE was incidentally detected during echocardiographic examination in a tertiary teaching hospital between Jan 2002 and Dec 2012. Total 151 patients with heart failure complicated with PE were analyzed. All patients' mortality data were collected from registry center of Social Insurance Institution which is officially responsible for recording all mortality data in Turkey. Detailed echocardiographic and hematologic parameters including creatinine, uric acid, albumin, sodium, potassium, hemoglobin at the time of hospital admission were analyzed. Data from 151 eligible patients were analyzed. We compared patients who died (n = 51) during follow-up with the survivors (n = 100) in terms of patients' echocardiographic and hematological features. Mean duration of follow-up was 71.5 ± 45.6 months. Fifty-one patients (33.8 %) died during this follow-up period. From all echocardiographic parameters only dilated left atrium (LA) diameter was found to be associated with a poor prognosis (p = 0.034). Low albumin, sodium and hemoglobin levels were associated with poor prognosis (p < 0.001, p = 0.002 and p = 0.007, respectively). We showed that dilated LA, as well as low albumin, low sodium and low hemoglobin levels had a worse prognostic significance than patients with normal LA size, within normal limits of albumin, sodium and hemoglobin levels in patients with heart failure complicated with PE determined incidentally by echocardiography.

Evaluation of atrial electromechanical delay and left atrial mechanical function in patients with obstructive sleep apnea : Cardiac involvement in patients with OSA

OBJECTIVE

The aim of this study was to evaluate atrial electromechanical delay measured by tissue Doppler imaging and left atrial mechanical function in patients with obstructive sleep apnea (OSA).

MATERIALS AND METHODS

Fourty-seven moderate-to-severe OSA patients who were newly diagnosed by polysomnography (Apnea-hypopnea index ≥ 15 events/h, 32 males, mean age 49.4 ± 11.5) and 30 patients who had no OSA in polysomnography (Apnea-hypopnea index < 5 events/h, 21 males, mean age 45.4 ± 9.1) were included in the study. Using tissue Doppler, diastolic functions, atrial electromechanical coupling were measured from the lateral mitral, septal, and tricuspid annulus. Inter, intra, and left atrial electromechanical delay were calculated (lateral-tricuspid, septum-tricuspid, lateral-septal). Left atrial volumes (maximal, minimal, and presystolic) were measured by the method of discs in the apical four-chamber view and were indexed to body surface area. Mechanical function parameters of the left atrium were also calculated.

RESULTS

Interatrial, intraatrial, and left atrial electromechanical delays were significantly higher in the OSA group compared to the control group. Passive emptying fraction was significantly decreased, volume at the beginning of atrial systole and active emptying volume were significantly increased in OSA patients compared to the controls. The apnea-hypopnea index was significantly associated with interatrial and intraatrial electromechanical delay, passive emptying fraction, and conduit volume.

CONCLUSIONS

Electromechanical delay was markedly prolonged and left atrial electromechanical function was impaired in untreated OSA patients. These impairments worsen with increasing severity of OSA.

Left atrial minimum volume and reservoir function as correlates of left ventricular diastolic function: impact of left ventricular systolic function

OBJECTIVE

Left atrial (LA) maximum volume (LAV(max)) is an indicator of left ventricular (LV) diastolic function. However, LAV(max) is also influenced by systolic events, whereas the LA minimum volume (LAV(min)) is directly exposed to LV pressure. The authors hypothesised that LAV(min) may be a better correlate of LV diastolic function than LAV(max).

DESIGN

Cross-sectional.

SETTING

University hospital.

PATIENTS

357 participants from a community-based cohort study.

METHODS

LA volumes and reservoir function, measured as total LA emptying volume (LAEV) and LA emptying fraction (LAEF), were assessed by real-time three-dimensional echocardiography. LV diastolic function was assessed by trans-mitral early (E) and late (A) Doppler velocities and mitral early diastolic velocity by tissue-Doppler (e'). LV systolic function was assessed by LV ejection fraction (LVEF) and global longitudinal strain (GLS) by speckle-tracking.

RESULTS

LAV(min) significantly increased with worsening diastolic dysfunction (p<0.001), whereas the increase in LAV(max) was less pronounced (p=0.07). LAEV and LAEF decreased with worsening diastolic dysfunction (both p<0.001). In linear regressions, LAV(min) and LAV(max) were significant predictors of E/e', with higher parameter estimates for LAV(min). In multivariate models, LAV(min) resulted strongly associated with E/e' (β=0.45, p<0.001), whereas LAV(max) was not (β=-0.16, p=0.08). LA reservoir function was better associated with GLS than LVEF. In multivariate analyses, GLS was significantly associated with LAV(max) (β=-0.15, p=0.002), LAEV (β=-0.37, p<0.001) and LAEF (β=-0.28, p<0.001) but not with LAV(min).

CONCLUSIONS

LAV(min) is a better correlate of LV diastolic function than LAV(max). The impact of LV longitudinal systolic function on LA reservoir function might explain the weaker relation between LAV(max) and LV diastolic function.

Left atrial volume: comparison of 2D and 3D transthoracic echocardiography with ECG-gated CT angiography

RATIONALE AND OBJECTIVES

Left atrial volume (LAV) measurement by conventional two-dimensional (2D) transthoracic echocardiography (TTE) may be limited by the geometric model, by suboptimal definition of left atrial endocardium, or by chamber foreshortening. Three-dimensional (3D) TTE is posited to eliminate chamber foreshortening, and LAV measurement by 3D TTE should be more reflective of true LAV. The aim of this study was to compare conventional 2D TTE and newer 3D TTE for measurements of LAV to multidetector computed tomographic (MDCT) measurements using automated chamber reconstruction (ACR).

MATERIALS AND METHODS

Twenty-two subjects consented to undergo 2D TTE and 3D TTE immediately prior to or following coronary computed tomographic angiography. LAV was calculated from 2D TTE using the area-length method (ALM) and from 3D TTE with the ALM as well as with a 3D model. Electrocardiographically gated coronary computed tomographic angiography was performed in helical mode. LAV was measured using the ALM as well as ACR.

RESULTS

LAV was significantly smaller by 2D TTE (80 ± 21 mL) and 3D-TTE (90 ± 24 mL with the ALM, 61 ± 16 mL with the 3D model) compared to MDCT ACR (120 ± 30 mL) (P < .01). Correlation between MDCT ALM and MDCT ACR was excellent (mean Δ = -1.4 ± 14 mL, r = 0.91). Correlation with MDCT ACR was no better for 3D TTE (r = 0.80) than for 2D TTE (r = 0.80).

CONCLUSIONS

LAV is underestimated by both 2D TTE and 3D TTE relative to coronary computed tomographic angiography. Excellent agreement between the ALM and ACR with MDCT imaging suggests that the geometric model plays a negligible role in the underestimation of LAV. Underestimation of LAV by echocardiography is likely related to suboptimal definition of left atrial contour.

Left atrial size is an independent predictor of overall survival in patients with primary systemic amyloidosis

BACKGROUND

Primary systemic amyloidosis is a severe plasma cell disorder characterized by the extracellular deposition of amyloid fibrils in different organs. Echocardiography is usually performed to assess cardiac involvement. We hypothesized that in patients with systemic amyloidosis, simple echocardiographic measurement of the left atrial (LA) diameter indexed to the body surface area might provide an important risk marker for this disease.

METHODS

Between 1997 and 2011, 134 patients were diagnosed with primary systemic amyloidosis and had echocardiography within 28 days; we collected their baseline characteristics and biological and echocardiographic data retrospectively. LA enlargement was defined as recommended as M-mode LA diameter greater or equal to 23 mm/m(2).

RESULTS

One hundred and eleven patients (83%) had echocardiographic LA dimension data available (mean age 63±11 years; 61% men; 31% previously diagnosed with systemic hypertension). Mean left ventricular ejection fraction (LVEF) and interventricular septum thickness (IVST) were 62±12% and 14±4 mm, respectively. Mean follow-up was 2.8±2.9 years (maximum 12 years). Patients with LA enlargement had a slightly lower LVEF (P=0.08) and a significantly greater IVST (P<0.0001). Overall, 5-year survival was 57±5%. However, 1-year and 5-year survival rates were markedly reduced in patients with LA enlargement versus those without LA enlargement (61±7% and 39±8% vs 83±5% and 72±7%, respectively; P=0.0007). On multivariable analysis, after adjusting for age, sex, LVEF, IVST, presence of hypertension and creatinine concentration, LA enlargement remained an independent predictor of overall mortality at 5 years (hazard ratio 2.47; 95% confidence interval 1.11-5.90; P=0.02).

CONCLUSION

LA enlargement, a surrogate marker of diastolic dysfunction, is an independent predictor of long-term mortality and may therefore help to enhance risk stratification and management of patients presenting with amyloidosis.

Left atrial volume in children without heart disease and in those with ventricular septal defect or patent ductus arteriosus or hypertrophic cardiomyopathy

In adults, the left atrial (LA) volume has been shown to reflect diastolic function and is a powerful predictor of cardiac morbidity and mortality. Normative LA volume values in children and the effect of loading conditions on the LA volume in those with congenital heart disease are lacking. The purposes of the present study were to (1) establish normal LA volume values for children, (2) assess the effect of left ventricular volume loading conditions on LA volume, and (3) describe the effect of abnormal myocardial relaxation on the LA volume. We retrospectively reviewed the echocardiograms from 3 pediatric cohorts: group N (n = 522), children with normal echocardiographic findings; group VSD/PDA (n = 71), children with ventricular septal defect (VSD; n = 50) or patent ductus arteriosus (PDA; n = 21); and group HC (n = 63), children with hypertrophic cardiomyopathy (HC). In group N, we identified the LA volume indexed to the body surface area (LA volume index) as a consistent measure of the LA volume in children 3 to 23 months old (mean 16 ± 3 ml/m(2)) and 2 to 17 years old (mean 22 ± 4 ml/m(2)). LA dilation was more common in group VSD/PDA than in group N (27% vs 2%, p <0.0001) and in children with moderate or large shunts than in those with smaller shunts (61% vs 5%, p <0.0001). In group HC, the LA volume index correlated with the mitral valve E/e' ratio (p <0.0001). In conclusion, this is the first study to establish normal pediatric LA volume values. The LA volume index is a reproducible measure of LA size in children ≥ 3 months old. The LA volume index reflects a chronically increased left ventricular volume load in children with VSD or PDA and chronically elevated left ventricular filling pressures in children with HC.

The reliability of chest radiographs in predicting left atrial enlargement

INTRODUCTION

Estimates of left atrial size in patients with suspected cardiac disease play an important role in predicting prognosis and events, as well as treatment decisions. Two methods are commonly used to estimate left atrial size: chest radiography and cardiac ultrasound. This study aims to determine the test characteristics by comparing the use of radiographs to cardiac ultrasound (the gold-standard test).

METHODS

Data from patients older than 18 years admitted to Steve Biko Academic Hospital during 2000-2003 who had both chest radiographs and cardiac ultrasound were included in this cross-sectional, retrospective analysis. Chest radiographs were classified into three quality classes, and the sub-carinal angle (SCA) and sub-angle distance (SAD) were measured twice in all available radiographs by two observers. Intra- and inter-observer variability (three methods) as well as the predictive value of the carinal angle and sub-angle distance measurements were determined using logistic regression (with left atrial enlargement - determined by ultrasound as comparator).

RESULTS

Data for 159 patients were available (154 cardiac ultrasounds and 178 chest radiographs). Intra-observer variability for chest radiograph measurements was low with almost perfect concordance (p = 0.000). Inter-observer variability was higher for supine radiographs. Using logistic regression, a linear model was identified which was statistically significant only for erect radiographs. While goodness-of-fit analysis showed that the model fits the data, performance characteristics were poor, with high sensitivity and low specificity, and an area under the ROC curve of 0.62-0.63, depending on type of radiograph and measurement (SCA or SAD). Linearity in the logit of the dependent variable was assessed, and found to be present at the extremes of SCA measurements for the supine radiograph data and in the first three quartiles for erect radiograph data. A nonlinear model determined by fractional polynomial analysis did not perform significantly better than the original linear model. Cut-off values for the SCA of 72° and 84° (erect and supine radiographs, respectively) were found to give the best compromise between sensitivity and specificity. The corresponding cut-off values for SAD were 24.1 and 26.9 mm.

CONCLUSION

Assessment of either SCA or SAD to determine left atrial size was equivalent and repeatable, both with the same observer and between two observers (less so for supine radiographs). While this measure was precise, it was found not to be very accurate. Therefore, chest radiographs are not reliable in predicting left atrial enlargement.

Comparison of echocardiographic single-plane versus biplane method in the assessment of left atrial volume and validation by real time three-dimensional echocardiography

BACKGROUND

The American Society of Echocardiography recommends calculating left atrial (LA) biplane volume because of its greater accuracy and prognostic value over LA diameter. However, biplane methods are not always feasible. The aim of this study was to assess the correlation between the echocardiographic LA biplane and single-plane volumes and their agreement in the classification of LA size when American Society of Echocardiography cutoffs are applied.

METHODS

Two-dimensional echocardiography was performed on the participants of the population-based Cardiovascular Abnormalities and Brain Lesions study. LA volume was calculated by the biplane area-length and single-plane modified Simpson's methods and validated against three-dimensional echocardiography.

RESULTS

The study sample consisted of 527 participants (mean age 69.6 +/- 9.7 years; 61.9% women). Both single-plane and biplane LA volumes correlated well with three-dimensional echocardiography (r = 0.93, P < .001). The correlation between the single-plane and biplane methods was excellent (r = 0.95, P < .001; intraclass correlation coefficient, 0.92; 95% confidence interval, 0.80-0.96). Categorical agreement between the single-plane and biplane methods was modest (kappa = 0.51; 95% confidence interval, 0.45-0.57; disagreement rate, 26.0%), mainly because of overestimation by the single-plane method. The correction of the single-plane volume by a regression equation improved the agreement (kappa = 0.70; 95% confidence interval, 0.64-0.76), but misclassifications remained in 14.0% of cases.

CONCLUSIONS

Single-plane and biplane LA volume measurements have strong correlations, but their agreement for categorical classification is suboptimal. Specific cutoff points should be developed for the single-plane method.