Left atrial distensibility and left ventricular filling pressure in acute versus chronic severe mitral regurgitation

Hydralazine combined with conventional therapy improved outcomes in severe systolic dysfunction and mitral regurgitation

AIMS

Patients with heart failure (HF) and reduced left ventricular ejection fraction (LVEF) accompanied by significant mitral regurgitation (MR) had poor outcome. Several vasodilator trials showed neutral results. We aimed to investigate the effect of early up-titration of hydralazine combined with conventional treatment in acute HF with severe systolic dysfunction and significant MR.

METHODS AND RESULTS

The study was open-labelled, one-to-one ratio randomized designed. Consecutively hospitalized patients with decompensated HF symptoms, LVEF < 35%, and MR more than moderate severity were enrolled after exclusion. All participants with inadequate preload should have intake promotion with/without fluid supply. Patients receiving evidence-based medications (EBMs) as conventional treatment served as the control. Hydralazine + conventional treatment group received up-titration of hydralazine at Days 1-5 of the index admission combined with EBMs and throughout the course of follow-up. The endpoints included cardiovascular (CV) death and HF rehospitalization. Totally, 408 patients were enrolled (203 in conventional treatment and 205 in hydralazine + conventional treatment). The mean follow-up period was 3.5 years. The mean dose of hydralazine was 191 mg at index admission and 264 mg at study end in hydralazine + conventional treatment group. Both groups did not significantly differ in prescription rates and dosages of EBMs (all P > 0.05) at study end. Side effects did not differ between the two groups. Finally, 51% (104 out of 203 cases) reached endpoints in conventional group and 34.6% (71 out of 205 cases) in hydralazine + conventional treatment group, which had a significant reduction in CV events (hazard ratio 0.613, 95% confidence interval 0.427-0.877, P < 0.001). In-hospital death during the index admission was significantly higher in conventional group (5.4% vs. 0.5%, respectively; P = 0.001).

CONCLUSIONS

When administered without inadequate preload, combining early up-titration of hydralazine with EBMs improves outcome in patients with severe systolic dysfunction and significant MR, and it is safe and well tolerated.

Left atrial expansion index measured with cardiovascular magnetic resonance estimates pulmonary capillary wedge pressure in dilated cardiomyopathy

BACKGROUND

Pulmonary capillary wedge pressure (PCWP) assessment is fundamental for managing dilated cardiomyopathy (DCM) patients. Although cardiovascular magnetic resonance (CMR) has become the gold-standard imaging technique for evaluating cardiac chamber volume and function, PCWP is not routinely assessed with CMR. Therefore, this study aimed to validate the left atrial expansion index (LAEI), a LA reservoir function parameter able to estimate filling pressure with echocardiography, as a novel CMR-measured parameter for non-invasive PCWP estimation in DCM patients.

METHODS

We performed a retrospective, single-center, cross-sectional study. We included electively admitted DCM patients referred to our tertiary center for further diagnostic evaluation that underwent a clinically indicated right heart catheterization (RHC) and CMR within 24 h. PCWP invasively measured during RHC was used as the reference. LAEI was calculated from CMR-measured LA maximal and minimal volumes as LAEI =  ( (LAVmax-LAVmin)/LAVmin) × 100.

RESULTS

We enrolled 126 patients (47 ± 14 years; 68% male; PCWP = 17 ± 9.3 mmHg) randomly divided into derivation (n = 92) and validation (n = 34) cohorts with comparable characteristics. In the derivation cohort, the log-transformed (ln) LAEI showed a strong linear correlation with PCWP (r = 0.81, p < 0.001) and remained a strong independent PCWP determinant over clinical and conventional CMR parameters. Moreover, lnLAEI accurately identified PCWP ≥ 15 mmHg (AUC = 0.939, p < 0.001), and the optimal cut-off identified (lnLAEI ≤ 3.85) in the derivation cohort discriminated PCWP ≥ 15 mmHg with 82.4% sensitivity, 88.2% specificity, and 85.3% accuracy in the validation cohort. Finally, the equation PCWP = 52.33- (9.17xlnLAEI) obtained from the derivation cohort predicted PCWP (-0.1 ± 5.7 mmHg) in the validation cohort.

CONCLUSIONS

In this cohort of DCM patients, CMR-measured LAEI resulted in a novel and useful parameter for non-invasive PCWP evaluation.

Cardiac Resynchronization Therapy and Left Atrial Remodeling: A Novel Insight?

Cardiac resynchronization therapy (CRT) restores ventricular dyssynchrony, improving left ventricle (LV) systolic function, symptoms, and outcome in patients with heart failure, systolic dysfunction, and prolonged QRS interval. The left atrium (LA) plays tremendous roles in maintaining cardiac function, being often inflicted in various cardiovascular diseases. LA remodeling implies structural-dilation, functional-altered phasic functions, and strain and electrical-atrial fibrillation remodeling. Until now, several important studies have approached the relationship between LA and CRT. LA volumes can predict responsiveness to CRT, being also associated with improved outcome in these patients. LA function and strain parameters have been shown to improve after CRT, especially in those who were positive responders to it. Further studies still need to be conducted to comprehensively characterize the impact of CRT on LA phasic function and strain, and, also, in conjunction with its impact on functional mitral regurgitation and LV diastolic dysfunction. The aim of this review was to provide an overview of current available data regarding the relation between CRT and LA remodeling.

Non-invasive evaluation of pulmonary capillary wedge pressure using the left atrial expansion index in mitral valve stenosis, prosthesis and repair

Pulmonary capillary wedge pressure (PCWP) non-invasive evaluation is limited in patients with mitral valve (MV) stenosis, prosthesis, and surgical repair. This study aimed to assess the left atrial expansion index (LAEI) measured through transthoracic echocardiography (TTE) as a novel parameter for estimating PCWP in these challenging cardiac conditions. We performed a retrospective, cross-sectional study, including chronic cardiac patients receiving within 24 h a clinically indicated right heart catheterization (RHC) and transthoracic echocardiographic (TTE) exam. PCWP measured during RHC was used as the reference. TTE measurements were performed offline, blinded to RHC results. LAEI was calculated as LAEI = [(LAmaxVolume-LAminVolume)/LAminVolume] × 100. We included 167 patients (age = 73 ± 11.5 years; PCWP = 18 ± 7.7 mmHg) with rheumatic mitral valve (MV) stenosis (16.2%), degenerative MV stenosis (51.2%), MV prosthesis (18.0%), and MV surgical repair (13.8%). LAEI correlated logarithmically with PCWP, and the log-transformed LAEI (lnLAEI) showed a good linear association with PCWP (r = - 0.616; p < 0.001). lnLAEI was an independent PCWP determinant, providing added predictive value over conventional clinical (age, atrial fibrillation, heart rate, MV subgroups) and echocardiographic variables (LVEF, MV effective orifice area, MV mean gradient, net atrioventricular compliance, and pulmonary arterial systolic pressure). lnLAEI identified PCWP > 12 mmHg with AUC = 0.870, p < 0.001; and PCWP > 15 mmHg with AUC = 0.797, p < 0.001, with an optimal cut-off of lnLAEI < 3.69. The derived equation PCWP = 36.8-5.5xlnLAEI estimated the invasively measured PCWP ± 6.1 mmHg. In this cohort of patients with MV stenosis, prosthesis, and surgical repair, lnLAEI resulted in a helpful echocardiographic parameter for PCWP estimation.

Enlarged left atrium and decreased left atrial strain are associated with atrial fibrillation in patients with hyperthyroidism irrespective of conventional risk factors

The purpose of this study was to investigate factors associated with AF in patients with hyperthyroidism beyond heart failure (HF), coronary heart disease (CHD), or valvular diseases. A total of 136 patients (mean age, 52 ± 15 years; 86 [63%] female) who were diagnosed with hyperthyroidism for the first time were enrolled. Patients who had HF, CHD, or significant valvular diseases were excluded. Patients were classified into two groups according to the presence (group 1, n = 40) and absence of AF (group 2, n = 96). AF occurred in 40 (29%) patients and 23 (58%) of these patients showed paroxysmal AF. Among the symptoms of hyperthyroidism, the most common chief complaint was palpitation (30%). Advanced age, presence of prior cerebrovascular events, and presence of palpitations were associated with AF. Larger left atrial volume index (LAVI), increased left ventricular mass index, and decreased left ventricular ejection fraction (LVEF) and S' velocity were associated with AF. Among them, presence of palpitations and increased LAVI were independently associated with the occurrence of AF. In addition, strain analysis, decreased LA expansion index (EI), ejection fraction (EF), peak atrial longitudinal strain, contraction strain, and late diastolic strain rate (A sr) and systolic strain rate (S sr) were associated with the occurrence of AF and LAVI. Presence of palpitations and enlarged left atrium were associated with the occurrence of AF in patients with hyperthyroidism irrespective of conventional risk factors. Additional LA analysis revealed that decreased LA function was associated with AF and enlarged left atrium.

Left Atrial Expansion Index for Noninvasive Estimation of Pulmonary Capillary Wedge Pressure: A Cardiac Catheterization Validation Study

BACKGROUND

Pulmonary capillary wedge pressure (PCWP) plays a pivotal role in cardiac disease diagnosis and management. Right heart catheterization (RHC) invasively provides accurate PCWP measurement, but it is impractical for widespread use in all patients. The left atrial expansion index (LAEI), measured on transthoracic echocardiography, describes the relative left atrial volume increase during the left atrial reservoir phase. The aim of this study was to validate LAEI as a noninvasive parameter for PCWP estimation.

METHODS

A total of 649 chronic cardiac patients (mean age, 66 ± 14 years; mean PCWP, 14 ± 7.6 mm Hg; mean left ventricular ejection fraction, 50 ± 15%) who underwent both clinically indicated RHC and transthoracic echocardiography within 24 hours were retrospectively enrolled. Patients were randomly divided into derivation (n = 509) and validation (n = 140) cohorts. PCWP was measured during RHC and defined as elevated when >12 mm Hg. Transthoracic echocardiographic parameters and LAEI were measured offline, blinded to RHC results.

RESULTS

In the derivation cohort, LAEI correlated logarithmically with PCWP, and the log-transformed LAEI (lnLAEI) correlated linearly with PCWP (r = -0.73, P < .001). lnLAEI showed an independent and additive predictive role for PCWP estimation over clinical and diastolic dysfunction (DD) parameters. The diagnostic accuracy of lnLAEI for elevated PCWP identification (area under the curve = 0.875, P < .001; optimal lnLAEI cutoff < 4.02) was higher than either the single DD parameters or their combination. In the validation cohort, lnLAEI cutoff < 4.02 showed higher accuracy than the 2016 DD algorithm (88% vs 74%) for elevated PCWP identification. Finally, the equation PCWP = 38.3 - 6.2 × lnLAEI, obtained from the derivation cohort, predicted invasively measured PCWP in the validation cohort.

CONCLUSIONS

In a cohort of patients with various chronic cardiac diseases, lnLAEI performed better than DD parameters and the 2016 DD algorithm for PCWP estimation. lnLAEI might be a useful echocardiographic parameter for noninvasive PCWP estimation.

Early reduction of left atrial function predicts adverse clinical outcomes in patients with severe aortic stenosis undergoing transcatheter aortic valve replacement

Aims

To investigate the changes in left atrial strain (LAS) after correction of severe aortic stenosis (AS) with transcatheter aortic valve replacement (TAVR) and assess its prognostic impact.

Methods and results

One hundred consecutive patients with severe symptomatic AS who underwent TAVR at the Magna Graecia University of Catanzaro underwent echocardiographic examination including assessment of LAS before and after TAVR. Independent investigators collected outcome data and information. The primary study outcome was the difference in ΔLAS (postTAVR–preTAVR) between patients those met the main clinical endpoint (a composite of cardiovascular mortality and heart failure hospitalisation) and those not meeting the endpoint.

During a median follow-up of 31 months, 35 patients (35%) met the combined clinical endpoint. The difference between LAS post-TAVR and LAS pre-TAVR (ΔLAS) was significantly larger in patients who met the combined endpoint (HR=0.76 (0.67–0.86); p<0.001). Multivariate logistic regression analysis including ΔLAS, EuroSCORE II and left ventricular ejection fraction showed that ΔLAS (HR=0.80, p<0.001) was the only independent predictor of the combined clinical endpoint. Finally, a Kaplan-Maier analysis showed that patients with a ΔLAS above its median value had a significantly better event-free survival compared with those below the median (p<0.001).

Conclusions

A lower reduction in ΔLAS after TAVR was an independent predictor of the primary composite outcome of cardiovascular death and hospitalisation for heart failure.

Left atrial strain and distensibility in relation to left ventricular dysfunction and prognosis in aortic stenosis

OBJECTIVE

To test the relationship between left atrial (LA) distensibility (LAD), LA strain (LAS), and left ventricular (LV) dysfunction and prognosis in aortic stenosis (AS).

METHODS

Transthoracic Doppler echocardiography was performed prospectively in 102 consecutive patients with AS (77 with severe, 25 with moderate, mean age 77 years). LA volume was calculated by the area-length method in apical four- and two-chamber views, immediately before mitral valve opening (Vol_max ) and at mitral valve closure (Vol_min ). LAD was defined as (Vol_max   - Vol_min ) × 100%/Vol_min . LAS (mean of maximal strain from the 4-2 chamber views) was conducted using a dedicated software package. The endpoint was hospitalization for heart failure and death from any cause.

RESULTS

Left atrial strain, LAD, and LA vol/m² were significantly correlated with LV diastolic parameters, and PASP (all, P < 0.05). However, LAD and LAS but not LA vol/m² were significantly correlated with Charlson score, LV global longitudinal strain, and to transaortic mean gradient (all, P < 0.05). At a median follow-up of 25 months, 53 patients had an event. LAS, LAD, LA vol/m², and Charlson index were associated with events (all, P < 0.05). In multivariate analysis, LAD, LAS, and Charlson index (all, P < 0.01) remained independently associated with events. Using a ROC curve analysis, LAD ≤ 69% and LAS ≤ 17% were the best cutoffs associated with an event.

CONCLUSION

In patients with moderate to severe AS, LAD and LAS are associated with LV dysfunction, AS severity, and are independently linked to events.

Effect of saline administration on left atrial pressure during transcatheter mitral valve repair

OBJECTIVES

To measure the intraprocedural change in left atrial pressure (LAP) with saline administration during transcatheter mitral valve repair (TMVR).

BACKGROUND

TMVR with MitraClip offers an alternative to surgery in select patients. During this procedure, large volumes of fluid are routinely administered with anesthesia and to facilitate transcatheter valve repair. LAP, a measure used to guide repair, may thereby change as a result of volume expansion, suggesting a need for continuous intracardiac pressure monitoring.

METHODS

Consecutive patients with severe mitral regurgitation underwent TMVR with MitraClip and continuous LAP monitoring through a dedicated sampling catheter. Specific LAP values were acquired immediately after transseptal access; before first clip deployment; and after deployment of the last clip.

RESULTS

151 patients (age 80 ± 8 years, 64% male) underwent TMVR with MitraClip and continuous LAP monitoring. Mean LAP and v-wave pressure increased significantly from baseline to pre-MitraClip deployment (P < 0.0001) and decreased significantly from deployment to procedure end (P < 0.0001). Linear regression of v-wave pressure change (from procedure start to clip deployment) relative to volume administration yielded a significantly nonzero slope (0.28 mmHg/min, P < 0.0001, r = 0.30).

CONCLUSION

Fluid administration during TMVR leads to time-dependent increases in LAP. Such intraprocedural change underscores the need for targeted, if not continuous, LAP measurement during TMVR to optimize MitraClip placement and mitral regurgitation reduction.

Long Term Outcomes of Left Atrial Reservoir Function in Children with a History of Kawasaki Disease

Background

Decreased left atrial (LA) reservoir function is reported to be associated with elevated left ventricular (LV) end diastolic pressure and LV diastolic dysfunction. Echocardiographic parameters that reflect LA reservoir function include LA total emptying fraction [(maximum LA volume - minimum LA volume) / maximum LA volume], peak LA longitudinal strain (PLALS) at systole, and LA stiffness index (E/E´/PLALS). We aimed to investigate the long-term outcomes of LV diastolic function in children with a history of Kawasaki disease (KD) (KDHx group) by assessing LA reservoir function.

Methods

Retrospectively, echocardiograms performed at a mean follow-up period of 5 years after the acute phase of KD in 24 children in the KDHx group were compared to those from 20 normal control subjects. LA total emptying fraction, PLALS, LA stiffness index, LV peak longitudinal systolic strain (ε), and strain rate (SR) were evaluated with conventional echocardiographic parameters.

Results

The mean age at long term follow-up echocardiography in children in the KDHx group was 6.8 years. Five children (20.8%) had coronary artery lesions (CALs) in the acute stage of KD. No children showed CALs at a mean follow-up period of 5 years after the acute phase of KD. There were no significant differences in the conventional echocardiographic parameters and in LA total emptying fraction, PLALS, LA stiffness index, LV peak longitudinal systolic ε, and SR, between the children in the KDHx and control group.

Conclusion

LV diastolic function assessed by LA reservoir function parameters at long-term follow-up in children in the KDHx group appears to be favorable.

Clinical Utility of Left Atrial Strain in Children in the Acute Phase of Kawasaki Disease

BACKGROUND

We aimed to evaluate the diagnostic utility of peak left atrial longitudinal strain (PALS) during left ventricular (LV) systole to differentiate children in the acute phase of Kawasaki disease (aKD) from controls. We also aimed to compare the diagnostic utility of PALS with those of conventional echocardiographic indices of diastolic function.

METHODS

Retrospectively measured PALS, LV longitudinal peak systolic strain, and strain rate obtained via velocity vector imaging were compared in a derivation cohort comprising 95 aKD and 67 controls. The utility of PALS in differentiating aKD from controls was compared with those of E/E', E/A, and maximum left atrial volume index (LAVImax). Derived cutoffs from receiver operating characteristic curves were validated in a separate validation cohort comprising 37 aKD and 19 controls.

RESULTS

In the derivation cohort, PALS was significantly decreased in aKD as compared with in controls. For differentiating aKD from controls, PALS outperformed E/E', E/A, and LAVImax. However, cutoffs of PALS (≤40% and ≤39%, before and after adjusting for the presence of significant mitral regurgitation and LV systolic dysfunction, respectively), like those of E/E', E/A, and LAVImax, showed low sensitivity and poor discriminative ability for differentiating aKD from controls. In the validation cohort, for differentiating aKD from controls, both cutoffs of PALS showed low sensitivity, like those of E/E', E/A, and LAVImax.

CONCLUSION

In aKD, impaired left atrial reservoir function could be detected as decreased PALS. For differentiating aKD from controls, PALS outperforms E/E', E/A, and LAVImax. However, like E/E', E/A, and LAVImax, PALS as a single parameter is limited in its clinical utility to differentiate aKD from controls because of its low sensitivity and poor discriminative ability.

Left atrial volume and function in dogs with naturally occurring myxomatous mitral valve disease

OBJECTIVE

Myxomatous mitral valve disease (MMVD) induces progressive left atrial (LA) enlargement. The LA modulates left ventricular filling and performance through its reservoir, conduit, and contractile function. Assessment of LA size and function may provide valuable information on the level of cardiac compensation. Left atrial function in dogs with naturally occurring MMVD remains largely unexplored. The objective of this study was to evaluate LA volume and function in dogs with naturally occurring MMVD.

ANIMALS

This prospective study included 205 client-owned dogs of different breeds, 114 healthy dogs, and 91 dogs with MMVD of different disease severities.

METHODS

Using two-dimensional echocardiography, the biplane area-length method was applied to assess LA volume and calculate volumetric indices of LA reservoir, conduit, and contractile function.

RESULTS

Left atrial volume and LA stroke volume increased, whereas LA reservoir and contractile function decreased with increasing disease severity. A maximal LA volume <2.25mL/kg was the optimal cut off identified for excluding congestive heart failure in dogs with chronic MMVD with a sensitivity of 96% and a specificity of 100%. An active LA emptying fraction <24% and/or a LA expansion index <126% were suggestive of congestive heart failure in dogs with chronic MMVD with a sensitivity of 77% and a specificity of 89% and a sensitivity of 82% and a specificity of 82%, respectively.

CONCLUSION

Dogs with MMVD appear to have larger LA volumes with poorer LA function. Deteriorating LA function, characterized by a decreasing reservoir and active contractile function, was evident in dogs with MMVD with increasing disease severity.

Diastolic Heart Failure Predicted by Left Atrial Expansion Index in Patients with Severe Diastolic Dysfunction

BACKGROUND

Left atrial (LA) echocardiographic parameters are increasingly used to predict clinically relevant cardiovascular events. The study aims to evaluate the LA expansion index (LAEI) for predicting diastolic heart failure (HF) in patients with severe left ventricular (LV) diastolic dysfunction.

METHODS

This prospective study enrolled 162 patients (65% male) with preserved LV systolic function and severe diastolic dysfunction (132 grade 2 patients, 30 grade 3 patients). All patients had sinus rhythm at enrollment. The LAEI was calculated as (Volmax - Volmin) x 100% / Volmin, where Volmax was defined as maximal LA volume and Volmin was defined as minimal volume. The endpoint was hospitalization for HF withp reserved LV ejection fraction (HFpEF).

RESULTS

The median follow-up duration was 2.9 years. Fifty-four patients had cardiovascular events, including 41 diastolic and 8 systolic HF hospitalizations. In these 54 patients, 13 in-hospital deaths and 5 sudden out-of-hospital deaths occurred. Multivariate analyses revealed that HFpEF was associated with LAEI.and atrial fibrillation during follow-up. For predicting HFpEF, the LAEI had a hazard ratio of 1.197per 10% decrease. In patients who had HFpEF events, the LAEI significantly (P< 0.0001) decreased from 69±18% to 39±11% during hospitalization. Although the LAEI improved during follow-up (53±13%), it did not return to baseline.

CONCLUSIONS

The LAEI predicts HFpEF in patients with severe diastolic dysfunction; it worsens during HFpEF events and partially recovers during followup.

Estimated pulmonary capillary wedge pressure assessed by speckle tracking echocardiography predicts successful ablation in paroxysmal atrial fibrillation

Background

Atrial fibrillation (AF) is associated with left atrial (LA) remodeling caused by pressure and/or volume (LAV) overload. Increased pulmonary capillary wedge pressure (PCWP) represents LA pressure overload. We recently reported that pulmonary capillary wedge pressure (ePCWP) can be estimated by the kinetics-tracking (KT) index that combines LA function and volume using speckle tracking echocardiography (STE), and has a strong correlation with PCWP measured by right heart catheterization (r = 0.92). Therefore, we hypothesized that ePCWP is the best echocardiographic predictor of successful AF ablation.

Methods

We enrolled 137 patients with paroxysmal AF (age: 61 ± 10 years) who underwent pulmonary vein isolation. We measured LAV index, LA emptying function (EF) and LA stiffness during sinus rhythm before ablation using STE. PCWP was noninvasively estimated by STE as we previously reported. Parameters were compared between a group with AF recurrence (n = 30, age: 59 ± 11 years) and a group with successful ablation (sinus rhythm maintained for >1 year) (n = 107, age 61 ± 11 years).

Results

The ePCWP was correlated with PCWP measured by right heart catheterization (r = 0.76, p < 0.01). Compared with the non-recurrence group (n = 107, age: 61 ± 11), the AF recurrence group had significantly increased ePCWP (10.6 ± 3.5 vs 14.6 ± 2.9 mmHg, p < 0.01), minimum LAV index (29 ± 12 ml/m² vs 37 ± 14 ml/m², p < 0.01) and LA stiffness (0.47 ± 0.33 vs 0.83 ± 0.59, p < 0.01), but lower total LA EF (44 ± 11 % vs 39 ± 13 %, p < 0.01) before ablation. In multivariate logistic regression analysis, ePCWP was the most significant independent predictor of successful ablation. Using 13 mmHg of PCWP as the optimal cutoff value, the sensitivity and specificity for successful ablation were 73 and 77 % (area under the curve = 0.81), respectively.

Conclusion

The ePCWP that is measured by the combination of LA function and volume before ablation was a better predictor of the successful ablation compared with LA function and volume separately. The ePCWP estimated by STE is useful to predict the successful ablation in paroxysmal AF, and could be useful to improve candidate selection for AF ablation.

Impact of gender and healthy aging on pulmonary capillary wedge pressure estimated by the kinetics-tracking index using two-dimensional speckle tracking echocardiography

Risk stratification in heart failure (HF) among patients and healthy subjects using pulmonary capillary wedge pressure (PCWP) is important for understanding when and why HF develops. The aim of the present study was to evaluate the impact of gender and healthy aging on estimated PCWP using a kinetics-tracking index in patients and in healthy subjects without hypertension. The study population consisted of 198 healthy subjects without cardiovascular or other systemic diseases and who were not taking any medications. Echocardiographic studies were performed using an ACUSON Sequoia 512 ultrasound system. Active left atrial (LA) emptying function (EF) was defined as (pre-atrial contraction LA volume-minimum LA volume)/pre-atrial contraction LA volume × 100%. With an increase in age, the E/A and E/e' ratios (markers of left ventricular (LV) diastolic dysfunction (DD)) showed a similar decrease in males and females. PCWP was maintained at 8.3±1.8 mm Hg in males and 8.2±2.3 mm Hg in females because of compensation by an increase in active LA EF. In contrast, the compensation for LV DD with an increase in active LA EF in females tended to be more gradual (slope=0.11) than in males (slope=0.18, P=0.060 vs. female). The parameters that indicated LV DD deteriorated with advancing age. PCWP might be maintained because of compensation, namely an increase in active LA EF in both males and females. The compensation in female septuagenarians and octogenarians was weaker than in male septuagenarians and octogenarians. This difference in compensation may explain why HF with preserved LV ejection fraction occurs more frequently in females than in males.

Left Atrial Expansion Index Predicts Left Ventricular Filling Pressure and Adverse Events in Acute Heart Failure With Severe Left Ventricular Dysfunction

BACKGROUND

The power of left atrial (LA) parameters for predicting left ventricular (LV) filling pressure and adverse events in acute heart failure (HF) with severe LV dysfunction, either sinus rhythm or atrial fibrillation (AF), is not fully understood.

METHODS AND RESULTS

Echocardiography was performed in 141 patients with acute decompensated congestive HF and LV ejection fraction <35%, including 42 with permanent AF. The LA expansion index was calculated as (Volmax - Volmin) × 100%/Volmin, where Volmax was defined as maximal and Volmin as minimal LA volume. Of 141 patients, invasive LV filling pressures within 12 hours of LA expansion index measurement were available in 109. The end points were 3-year frequencies of HF hospitalization and all-cause mortality. Over a median follow-up of 3.1 years, 74 participants (52.5%) reached the end points (sinus vs AF group: 48.5% vs 61.9%, respectively; P = .047). Multivariate analysis revealed that adverse events of both groups were only independently associated with age and LA expansion index. Rates of adverse events were proportional to LA expansion index. There was a good logarithmic relationship between LA expansion index and LV filling pressure, regardless of presence or absence of AF.

CONCLUSIONS

LV filling pressure can be estimated well by LA expansion index, with or without AF. The LA expansion index predicts adverse events in HF patients with severe systolic dysfunction. (ClinicalTrials.gov number: NCT01307722).

Noninvasive estimation of pulmonary capillary wedge pressure in patients with mitral regurgitation: A speckle tracking echocardiography study

BACKGROUND

Echocardiographic parameters to predict pulmonary capillary wedge pressure (PCWP) in mitral regurgitation (MR) are not yet elucidated. We reported that PCWP could be accurately estimated by novel KT index which is defined as log10[left atrial (LA) emptying function (EF)/LA volume]. We examined the usefulness of the KT index as a predictor of PCWP in primary and secondary MR with sinus rhythm and also MR with atrial fibrillation.

METHODS

LA dimension, strain, volume, EF, and E/e' were measured in moderate to severe MR with sinus rhythm (n=58, age: 67±8 years) and MR with atrial fibrillation (n=24, age: 69±11 years) just before catheterization and in normal subjects (n=26, age: 67±11 years) using speckle tracking echocardiography. MR with sinus rhythm was divided into primary MR (n=27) and secondary MR (n=31). The estimated PCWP (ePCWP) was calculated as 10.8-12.4×KT index.

RESULTS

There was a correlation between PCWP and LA dimension, E/e', minimum LA volume index, active LAEF, total LAEF, or LA strain (r=0.32, r=0.31, r=0.55, r=-0.61, r=-0.51, and r=-0.50, respectively, p<0.05). The better correlation was found between PCWP and ePCWP in MR including both primary and secondary MR and also MR with atrial fibrillation (r=0.70, r=0.67, and r=0.58, respectively, p<0.01). Multiple regression analysis revealed that ePCWP was an independent predictor of PCWP in MR. The ePCWP demonstrated good diagnostic accuracy (area under the curve of 0.86) and sensitivity (81%) and specificity (71%) to predict elevated PCWP >15mmHg using a cut-off of 16mmHg.

CONCLUSION

The ePCWP was the reliable echocardiographic parameter to predict PCWP in primary and secondary MR and might also be useful in MR with atrial fibrillation. The ePCWP may have an incremental value in a clinical setting.

A novel ultrasound predictor of pulmonary capillary wedge pressure assessed by the combination of left atrial volume and function: A speckle tracking echocardiography study

BACKGROUND

We hypothesized that a development of a novel index based on the combination of left atrial volume (LAV) and left atrial (LA) function evaluated by the time-LA volume curve using speckle tracking echocardiography (STE) would be accurate and useful to estimate pulmonary capillary wedge pressure (PCWP). Our goal was to develop a novel index of PCWP based on a combination of LAV and LA function using STE.

METHODS

A cross-validation study was performed with the patients divided into a training study to define the novel index (n=50) and a testing study to validate the index (n=196). PCWP was measured by right heart catheterization, and phasic LAV and emptying function (EF) were measured by STE.

RESULTS

Simple linear regression analysis in the training study revealed that the novel index that best estimated PCWP was the kinetics-tracking index [KT index=log10 (active LAEF/minimum LAV index)]. Multiple regression analysis revealed that the KT index was the most reliable predictor of PCWP. It had the strongest correlation with PCWP (r=-0.86, p<0.001) among all echocardiographic parameters. In the testing study, PCWP estimated by the KT index was also strongly correlated with measured PCWP (r=0.92, p<0.001). These correlations were also strong in the patients with reduced left ventricular ejection fraction (<50%), chronic heart failure, and chronic atrial fibrillation (r=0.92, r=0.91, r=0.79, p<0.001, respectively).

CONCLUSIONS

A novel index (KT index) using a combination of LAV and LA function was a powerful and useful predictor of PCWP and may be valuable in routine clinical practice.

The three integrated phases of left atrial macrophysiology and their interactions

Our understanding of the left atrium is growing, although there are many aspects that are still poorly understood. The left atrium size as an imaging biomarker has been consistently shown to be a powerful predictor of outcomes and of different cardiovascular disorders, such as, but not limited to, atrial fibrillation, congestive heart failure, mitral regurgitation and stroke. Left atrial function has been conventionally divided into three integrated phases: reservoir, conduit and booster-pump. The highly dynamic left atrium and its response to the stretch and secretion of atrial neuropeptides leaves the left atrium far from being a simple transport chamber. The aim of this review is to provide an understanding of the left atrial physiology and its relation to disorders within the heart.

Left atrial expansion index predicts atrial fibrillation in dyspnea

BACKGROUND

The left atrial (LA) expansion index for predicting atrial fibrillation (AF) in a relatively low-risk cohort is not fully understood.

METHODS AND RESULTS

In this prospective study of 2,200 dypnea patients, the LA expansion index was calculated as (Volmax-Volmin)×100%/Volmin, where Volmax was defined as maximum LA volume and Volmin was defined as minimum volume. The endpoints were 2-year frequency of AF, including both paroxysmal and persistent. Of the 180 participants (8.2%) who had AF attacks over a median follow-up of 2.7 years, 90 (4.1%) had at least 1 episode of persistent AF. Compared to patients with paroxysmal AF, those with persistent AF had a much lower LA expansion index (100±59% vs. 44±24%). LA expansion index was associated exponentially with the incidence of persistent AF. Independent predictors of AF included age, renal function impairment, pulmonary artery systolic pressure, and LA expansion index. Persistent AF, however, had significant independent associations only with prior heart failure, renal function impairment, diastolic dysfunction, and LA expansion index (odds ratio, 0.970; 95% confidence interval: 0.959-0.981 per 1% increase, P<0.0001). Compared to other parameters, LA expansion index <61.4% was the best cut-off point to predict persistent AF.

CONCLUSIONS

The LA expansion index is associated with the presence of AF, and a reduced LA expansion index has a strong association with persistent AF.

Left atrial expansion index predicts all-cause mortality and heart failure admissions in dyspnoea

AIMS

The power of left atrial (LA) parameters for predicting adverse events in relatively low-risk groups is not fully understood. This study investigated whether the LA expansion index predicts heart failure (HF) and all-cause mortality in subjects with dyspnoea.

METHODS AND RESULTS

Echocardiography was performed to identify causes of dypnoea in 1735 patients. The LA expansion index was calculated as (Volmax - Volmin) × 100%/Volmin, where Volmax was defined as the maximal LA volume and Volmin was defined as the minimal LA volume. The endpoints were 2-year frequencies of HF hospitalization and all-cause mortality. Over a median follow-up of 2.7 years, 91 participants reached endpoints. Rates of adverse events were exponentially proportional to the LA expansion index. For predicting adverse events, the LA expansion index was better than the maximal indexed LA volume and tissue Doppler parameters. Hospitalization for HF was independently associated with age, LVEF, pulmonary artery systolic pressure, LA expansion index, and history of prior HF. All-cause mortality was associated with age, pulmonary artery systolic pressure, and LA expansion index. Compared with the highest quartile of the LA expansion index, the lowest quartile had a 3.1-fold higher hazard of HF events and a 17.8-fold higher hazard of all-cause mortality.

CONCLUSIONS

The LA expansion index predicts adverse events in patients with dyspnoea. The prognostic power of the index exceeds that of other well-established echocardiographic parameters such as E/e' and maximal indexed LA volume. Trial registration NCT01171040.

Comparison of left atrial volume parameters in detecting left ventricular diastolic dysfunction versus tissue Doppler recordings

Because of diastolic coupling between the left atrium and left ventricle, we hypothesized that left atrial (LA) function mirrors the diastolic function of left ventricle. The aims of this study were to assess whether LA volume parameters can be good indexes of left ventricular diastolic dysfunction. Six hundred fifty-nine patients underwent cardiac catheterization and measurements of left ventricular filling pressure (LVFP). Echocardiographic examinations including tissue Doppler and LA volumes were also assessed. Ratio of early diastolic mitral inflow velocity to early diastolic mitral annular velocity and LVFP tended to increase after progression of diastolic dysfunction. The inverse phenomenon existed in LA ejection and LA distensibility. LA distensibility was superior to LA ejection fraction and early diastolic mitral inflow velocity/early diastolic mitral annular velocity for identifying LVFP >15 mm Hg (areas under receiver operating characteristic curve 0.868, 0.834, and 0.759, respectively) and for differentiating pseudonormal from normal diastolic filling (areas under receiver operating characteristic curve 0.962, 0.907, and 0.741, respectively). Multivariate logistic regression showed that LA ejection fraction and LA distensibility were associated significantly with the presence of pseudonormal/restrictive ventricular filling. In conclusion, LA volume parameters can identify LVFP >15 mm Hg and differentiate among patterns of ventricular diastolic dysfunction. For assessing diastolic function LA parameters offer better performance than even tissue Doppler.

Left atrial expansion index for predicting atrial fibrillation and in-hospital mortality after coronary artery bypass graft surgery

BACKGROUND

Atrial fibrillation (AF), a common complication after coronary artery bypass graft surgery (CABG), is associated with prolonged hospital stay. This prospective study assessed the accuracy of left atrial parameters and additional preoperative characteristics for predicting post-CABG AF and in-hospital mortality.

METHODS

A total of 197 patients without hemodynamic-significant valvular problems, who received isolated CABG, were enrolled. Echocardiography was performed before CABG.

RESULTS

Compared with patients without post-CABG AF, those with post-CABG AF were older (71 vs 64 years, p<0.0001), had a higher incidence of CABG during index hospitalization of acute myocardial infarction and preoperative respiratory failure requiring ventilator support, lower left ventricular ejection fraction (0.41 vs 0.48, p<0.0001), lower left atrial expansion index (52.2% vs 93.3%, p<0.0001), and higher left ventricular filling pressure (24.2 vs 19.1 mm Hg, p<0.0001). Multivariate analysis of preoperative variables showed that independent predictors of AF included age (odds ratio [OR], 1.064; 95% confidence interval [CI], 1.022 to 1.107 per 1-year increase; p 0.002), maximal indexed left atrial volume (OR, 1.026; 95% CI, 1.002 to 1.051 per 1 mL/m2 increase; p 0.037) and left atrial expansion index (OR, 0.981; 95% CI, 0.962 to 0.998 per 1% increase; p 0.029). The left atrial expansion index was also significantly associated with in-hospital mortality (OR, 0.982; 95% CI, 0.951 to 0.996 per 1% increase; p 0.042). Incidence of post-CABG AF in patients with left atrial expansion index less than 120% progressively increased as left atrial expansion index decreased.

CONCLUSIONS

Left atrial expansion index independently predicts post-CABG AF and in-hospital mortality.

Left atrial distensibility and E/e' for estimating left ventricular filling pressure in patients with stable angina. -A comparative echocardiography and catheterization study-

BACKGROUND

Although E/e' (the ratio of early diastolic mitral inflow velocity to early diastolic mitral annular velocity) is widely used to measure left ventricular filling pressure (LVFP), its accuracy is questionable in coronary artery disease patients.

METHODS AND RESULTS

Echocardiograms and LVFP were obtained from 174 patients with stable angina (Canadian Cardiovascular Society angina grade I-II) who had received interventions for angiography-confirmed coronary stenosis. Compared with single-vessel groups, the multiple-vessel group exhibited lower mitral annular velocities, higher LVFP, and stronger correlations between E/regional e' and LVFP. Additionally, stronger correlations between E/regional e' and LVFP existed in patients with systolic dysfunction or lower variation of myocardial performance index (MPI) among anterior, inferior and lateral borders of mitral annulus. Average e' was not superior to any regional e' for assessing LVFP by the E/e' method. E/e' and left atrial (LA) ejection fraction (EF) correlated linearly with LVFP, but the correlation between LA distensibility and LVFP was logarithmical. Compared with E/e', LA distensibility and LAEF were superior for identifying high LVFP.

CONCLUSIONS

E/e' is not completely satisfactory for assessing LVFP in patients with stable angina, especially those with single-vessel disease, preserved systolic function or high MPI variation. For identifying high LVFP, LA distensibility and LAEF are better than E/e'.

Left atrial parameters in the estimation of left ventricular filling pressure and prognosis in patients with acute coronary syndrome

Because left atrial (LA) volume plays a critical role in determining cardiovascular outcomes, it was hypothesized that this might be related to the distensibility of the left atrium and how this relates to left ventricular filling pressure (LVFP). Echocardiographic estimates of LVFP were compared to cardiac catheterization measurements in 521 consecutive patients with acute myocardial infarction and correlated with short- and long-term outcomes. Receiver-operating characteristic curve analysis was performed to investigate the sensitivity and specificity of echocardiographic parameters for predicting elevated LVFP (> 15 mm Hg). LA distensibility was calculated as (maximal volume - minimal volume) × 100%/minimal volume(.) and was found to be logarithmically associated with LVFP (p < 0.0001). LA distensibility was superior to mitral E/annular Em for identifying increased LVFP (area under the receiver-operating characteristic curve 0.92 vs 0.78). A total of 44 patients died during hospitalization, and 89 patients had died or experienced heart failure requiring rehospitalization at 12-month follow-up. In a multivariate Cox regression model, LA distensibility was an independent predictor of in-hospital mortality (hazard ratio 2.373 for LA distensibility ≤ 60%, p = 0.026), while LA volume was an independent prognostic factor of 1-year death or heart failure (hazard ratio 2.266 for LA volume ≥ 34 ml/m², p = 0.007). In conclusion, LA distensibility accurately identifies patients with increased LVFP after acute myocardial infarction and is an independent predictor of in-hospital mortality.