Index-Beat Assessment of Left Ventricular Systolic and Diastolic Function during Atrial Fibrillation Using Myocardial Strain and Strain Rate

Modified Haller Index is inversely associated with asymptomatic status in atrial fibrillation patients undergoing electrical cardioversion: a preliminary observation

BACKGROUND

No previous study evaluated the possible influence of chest wall conformation on symptoms perception in atrial fibrillation (AF) patients candidates for electrical cardioversion (ECV). We aimed at evaluating the anthropometric and clinical characteristics of patients with persistent AF undergoing ECV, categorized according to the presence or absence of symptoms.

METHODS

This study retrospectively analyzed a series of persistent AF patients scheduled for early ECV who underwent pre-procedural clinical evaluation, MHI (the ratio of chest transverse diameter over the distance between sternum and spine) assessment, transthoracic and transesophageal echocardiography implemented with strain analysis of both left atrium and left atrial appendage. Thromboembolic risk and burden of comorbidities were assessed by CHA2DS2-VASc Score and Charlson Comorbidity Index (CCI), respectively. The independent predictors of "asymptomatic AF" were assessed.

RESULTS

A total of 25 asymptomatic and 90 symptomatic AF patients were retrospectively examined. Compared to symptomatic AF patients, those asymptomatic were significantly older (78.4±3.8 vs. 71.0±7.7 years, P<0.001), predominantly males (84 vs. 44.4%, P<0.001), with significantly lower MHI (2.0±0.1 vs. 2.4±0.1, P<0.001), higher CHA2DS2-VASc Score (5.8±1.1 vs. 3.6±1.1, P<0.001) and CCI (6.8±1.4 vs. 2.3±0.9, P<0.001), and greater impairment in biventricular systolic function and atrio-auricolar myocardial strain indices. On multivariate logistic regression analysis, CHA2DS2-VASc Score (OR=2.65, 95% CI: 1.53-4.60) and CCI (OR=2.36, 95% CI: 1.16-4.66) were linearly associated with the endpoint "asymptomatic AF," whereas MHI (OR 0.76, 95% CI 0.59-0.97) was inversely associated with the asymptomatic status. A MHI <2.2 was the best cut-off for detecting asymptomatic AF patients.

CONCLUSIONS

MHI is inversely associated with asymptomatic status in persistent AF patients undergoing ECV. MHI assessment might represent an innovative practical approach to AF patients.

Two-dimensional speckle tracking imaging analyses of the correlations between left atrial appendage function and stroke risk in nonvalvular atrial fibrillation patients

Stroke incidence is the most severe complication associated with atrial fibrillation (AF), and the most common site of thrombus formation in AF patients is the left atrial appendage (LAA). This study was developed to use two-dimensional speckle tracking imaging (2D-STI) to explore associations between LAA strain/strain rate and stroke incidence and to evaluate the value of utilizing LAA strain and strain rate values to support the stratification of nonvalvular AF (NVAF) patients based on stroke risk. A total of 486 AF patients who had undergone transesophageal echocardiography to exclude potential intracardiac thrombosis between March 2021 and November 2022 were consecutively enrolled. Patients meeting the inclusion criteria were separated into two groups according to their history of stroke/transient ischemic attack (TIA). LAA strain and strain rate values in these patients were measured via 2D-STI. Multivariable logistic regression analysis was employed to determine independent risk factors for the construction of a combined predictive model. Of the 333 analyzed patients (134 females, aged 65 (56,72) years), 39 (11.71%, 39/333) had a history of stroke at the time of evaluation. Multivariate logistic regression analysis demonstrated that nonparoxysmal AF, CHA2DS2VASc score, LAA thrombus/spontaneous echo contrast (SEC), LAA strain, and strain rate were all predictors of stroke incidence among NVAF patients. The combined predictive model demonstrated excellent discriminative ability, with an AUC of 0.91 (95%CI 0.87-0.95, P < 0.001), and a sensitivity and specificity of 79.49% and 89.46%, respectively. The Hosmer-Lemeshow test confirmed good calibration, yielding a value of 0.98. Comparative decision curve analysis showed that the model provided superior net benefits compared to the CHA2DS2VASc score. Furthermore, the model exhibited improved predictive performance and reclassification for stroke when compared to the CHA2DS2VASc score (AUC 0.91 vs. 0.88, Z = 2.32, P = 0.02), accompanied by a significant increase in the net reclassification index (+ 5.44%, P < 0.001) and integrated discrimination improvement (8.21%, P < 0.001). These data demonstrate that LAA strain and strain rate, as measured via 2D-STI, can offer value when assessing LAA function in AF patients, potentially providing further predictive value to extant clinical risk scoring strategies.

Quantitative assessment of left ventricular myocardial work in patients with different types of atrial fibrillation by non-invasive pressure-strain loop technique

OBJECTIVE

This study aimed to analyze myocardial work in patients with atrial fibrillation (AF) using a noninvasive pressure strain loop (PSL) technique to provide a basis for the quantitative assessment of left ventricular (LV) systolic function.

METHODS

LV myocardial work of 107 AF patients (56 with paroxysmal atrial fibrillation and 51 with persistent atrial fibrillation) and 55 healthy individuals were assessed by the noninvasive PSL and then compared.

RESULTS

Global longitudinal strain (GLS) in absolute values, global work index (GWI), global constructive work (GCW), and global work efficiency (GWE) were significantly lower in the AF group than control group, whereas peak strain dispersion (PSD) and global wasted work (GWW) were significantly higher (P < .05). Further subdivision according to the AF type revealed that, compared with the controls, GLS in absolute values and GWE decreased significantly; PSD and GWW increased significantly in the paroxysmal AF group (P < .05). Nevertheless, GWI and GCW were not significantly different between paroxysmal AF and control groups (P > .05). Compared to paroxysmal AF, persistent AF induced a further decrease in absolute GLS and GWE and a further increase in GWW (P < .05), but PSD did not increase further (P > .05). Multiple linear regression analysis showed that GWI and GCW were independently associated with systolic blood pressure. GWW was associated with types of AF and left atrial volume index (LAVI). GWE was correlated with age, types of AF, disease duration, and LAVI. Receiver operating characteristic curve analysis showed that the area under the curve predicting myocardial injury was higher for GWE and GWW than for GLS (area under the curve:  .880,  .846, and  .821, respectively).

CONCLUSIONS

Non-invasive PSL can quantitatively assess LV systolic function in patients with different kinds of AF and detect early subclinical myocardial injury in patients with paroxysmal AF. GWE and GWW outperform GLS and LV ejection fraction when assessing myocardial injury. Systolic blood pressure, type of AF, LVAI, disease duration, and age may be associated with myocardial injury in patients with AF.

Transcatheter edge-to-edge mitral valve repair with extended clip arms for ventricular functional mitral regurgitation

BACKGROUND

The new sizing options of the MitraClip system (Abbott Vascular, Abbott Park, IL, USA) with extended clip arms were recently developed. Its applicability and effectiveness for ventricular functional mitral regurgitation (VFMR) are yet to be investigated.

METHODS

We retrospectively reviewed consecutive patients with symptomatic VFMR who underwent transcatheter edge-to-edge repair between 2018 and 2022 at the Sakakibara Heart Institute. Pre- and post-procedural mitral valve morphologies were assessed using three-dimensional transesophageal echocardiography.

RESULTS

In a total of 104 VFMR patients, the posterior mitral leaflet length was 12.8 ± 2.8 mm and 92 % was indicative of the extended arm (≥9 mm). Although baseline VFMR was more severe in the patients treated with the extended arms (n = 35, XT group) than the patients treated with the standard arms (n = 69, NT group), the decrease in VFMR was greater in the XT group (delta three-dimensional vena contracta area - 43 ± 33 mm2 vs. -31 ± 22 mm2, p = 0.030) and residual VFMR was similar between the groups, with a significantly greater reduction in the mitral annulus anterior-posterior diameter (-4.9 ± 2.2 mm vs -3.1 ± 2.1 mm, p < 0.001) and mitral annulus area in the XT group. The use of extended arms was independently associated with shorter procedure time (81 ± 26 min vs 108 ± 41 min) after adjustment for device generation and the number of clips (p = 0.017).

CONCLUSIONS

Most VFMR patients had enough leaflet lengths for transcatheter edge-to-edge repair using the MitraClip with the extended arms, which was associated with shorter procedure time and a greater decrease in the mitral annular size.

Validation of E/e' Using the Index-Beat Method as an Estimate of Left Atrial Pressure in Patients with Atrial Fibrillation

INTRODUCTION

Echocardiographic assessment of diastolic function during atrial fibrillation (AF) remains challenging due to the irregular cardiac cycle length. We sought to assess whether the index-beat method, the beat following two preceding cardiac cycles of equal duration, could provide a more reliable measurement of E/e' (mitral E wave/diastolic tissue Doppler velocity) than the conventional averaging of consecutive beats and hence facilitate the noninvasive estimation of elevated left atrial pressure (LAP) in patients with AF.

METHODS

We prospectively studied 35 patients with persistent AF who had preserved left ventricular ejection fraction and underwent radiofrequency ablation. LAP was measured in conjunction with transseptal puncture during catheter ablation. Echocardiography was performed 24 h before ablation and E/e' was determined using the recommended averaging of 10 beats and the index-beat method, with the observers blinded to the clinical details and LAP measurements.

RESULTS

Correlation analysis showed a strong positive correlation between two methods in terms of both septal E/e' (r = 0.841, p < 0.001) and lateral E/e' (r = 0.930, p < 0.001). Bland-Altman analysis also showed a good agreement between the two measurement methods in terms of E/e'. E/e' determined using both conventional averaging and the index-beat method was significantly correlated with LAP (p < 0.05). After Fisher Z transformation, we found that the index-beat septal E/e' had a better correlation with LAP than did the conventional averaging E/e' (r = 0.736 vs. r = 0.392, Zr = -2.110, p = 0.035). Furthermore, the index-beat method took significantly less time to measure E/e' (mean 33.6 s; 95% confidence intervals [CIs]: 32.1 s-36.2 s) than did conventional averaging method (mean 96.2 s; 95% CI: 90.2 s-102.3 s; p < 0.001). Receiver operating characteristic curve analysis revealed that the optimal cut-off for predicting mean LAP >12 mm Hg was 11 (sensitivity 100%; specificity 77.3%) for index-beat septal E/e' and 16 (sensitivity 61.5%; specificity 95.5%) for index-beat lateral E/e'.

CONCLUSIONS

Good correlations were found between E/e' and LAP in patients with AF, particularly with the index-beat method. Moreover, the index-beat method can easily measure E/e' at an accuracy similar to that for the conventional averaging of consecutive beats, which can therefore be applied to assess the diastolic dysfunction and potentially improve the diagnosis of heart failure in patients with AF.

Arrythmia-Mediated Valvular Heart Disease

The aging population is rising at record pace worldwide. Along with it, a steep increase in the prevalence of atrial fibrillation and heart failure with preserved ejection fraction is to be expected. Similarly, both atrial functional mitral and tricuspid regurgitation (AFMR and AFTR) are increasingly observed in daily clinical practice. This article summarizes all current evidence regarding the epidemiology, prognosis, pathophysiology, and therapeutic options. Specific attention is addressed to discern AFMR and AFTR from their ventricular counterparts, given their different pathophysiology and therapeutic needs.

Prognostic value of temporal patterns of left atrial reservoir strain in patients with heart failure with reduced ejection fraction

BACKGROUND

We investigated whether repeatedly measured left atrial reservoir strain (LASr) in heart failure with reduced ejection fraction (HFrEF) patients provides incremental prognostic value over a single baseline LASr value, and whether temporal patterns of LASr provide incremental prognostic value over temporal patterns of other echocardiographic markers and NT-proBNP.

METHODS

In this prospective observational study, 153 patients underwent 6-monthly echocardiography, during a median follow-up of 2.5 years. Speckle tracking echocardiography was used to measure LASr. Hazard ratios (HRs) were calculated for LASr from Cox models (baseline) and joint models (repeated measurements). The primary endpoint (PEP) comprised HF hospitalization, left ventricular assist device, heart transplantation, and cardiovascular death.

RESULTS

Mean age was 58 ± 11 years, 76% were men, 82% were in NYHA class I/II, mean LASr was 20.9% ± 11.3%, and mean LVEF was 29% ± 10%. PEP was reached by 50 patients. Baseline and repeated measurements of LASr (HR per SD change (95% CI) 0.20 (0.10-0.41) and (0.13 (0.10-0.29), respectively) were both significantly associated with the PEP, independent of both baseline and repeated measurements of other echo-parameters and NT-proBNP. Although LASr was persistently lower over time in patients with PEP, temporal trajectories did not diverge in patients with versus without the PEP as the PEP approached.

CONCLUSION

LASr was associated with adverse events in HFrEF patients, independent of baseline and repeated other echo-parameters and NT-proBNP. Temporal trajectories of LASr showed decreased but stable values in patients with the PEP, and do not provide incremental prognostic value for clinical practice compared to single measurements of LASr.

Prognostic value of temporal patterns of global longitudinal strain in patients with chronic heart failure

Background

We investigated whether repeatedly measured global longitudinal strain (GLS) has incremental prognostic value over repeatedly measured left ventricular ejection fraction (LVEF) and N-terminal pro B-type natriuretic peptide (NT-proBNP), and a single "baseline" GLS value, in chronic heart failure (HF) patients.

Methods

In this prospective observational study, echocardiography was performed in 173 clinically stable chronic HF patients every six months during follow up. During a median follow-up of 2.7 years, a median of 3 (25th-75th percentile:2-4) echocardiograms were obtained per patient. The endpoint was a composite of HF hospitalization, left ventricular assist device, heart transplantation, cardiovascular death. We compared hazard ratios (HRs) for the endpoint from Cox models (used to analyze the first available GLS measurements) with HRs from joint models (which links repeated measurements to the time-to-event data).

Results

Mean age was 58 ± 11 years, 76% were men, 81% were in New York Heart Association functional class I/II, and all had LVEF < 50% (mean ± SD: 27 ± 9%). The endpoint was reached by 53 patients. GLS was persistently decreased over time in patients with the endpoint. However, temporal GLS trajectories did not further diverge in patients with versus without the endpoint and remained stable during follow-up. Both single measurements and temporal trajectories of GLS were significantly associated with the endpoint [HR per SD change (95%CI): 2.15(1.34-3.46), 3.54 (2.01-6.20)]. In a multivariable model, repeatedly measured GLS maintained its prognostic value while repeatedly measured LVEF did not [HR per SD change (95%CI): GLS:4.38 (1.49-14.70), LVEF:1.14 (0.41-3.23)]. The association disappeared when correcting for repeatedly measured NT-proBNP.

Conclusion

Temporal evolution of GLS was associated with adverse events, independent of LVEF but not independent of NT-proBNP. Since GLS showed decreased but stable values in patients with adverse prognosis, single measurements of GLS provide sufficient information for determining prognosis in clinical practice compared to repeated measurements, and temporal GLS patterns do not add prognostic information to NT-proBNP.

Atrial Functional Mitral Regurgitation: A JACC: Cardiovascular Imaging Expert Panel Viewpoint

Functional or secondary mitral regurgitation (MR) is associated with increased cardiovascular morbidity and mortality. Mechanistically, secondary MR is attributable to an imbalance between mitral leaflet tethering and closure forces, leading to poor coaptation. The pathophysiology of functional MR is most often the result of abnormalities in left ventricular function and remodeling, seen in ischemic or nonischemic conditions. Less commonly and more recently recognized is the scenario in which left ventricular geometry and function are preserved, the culprit being mitral annular enlargement associated with left atrial dilatation, termed atrial functional mitral regurgitation (AFMR). This most commonly occurs in the setting of chronic atrial fibrillation or heart failure with preserved ejection fraction. There is variability in the published reports and in current investigations as to the definition of AFMR. This paper reviews the pathophysiology of AFMR and focus on the need for a collective definition of AFMR to facilitate consistency in reported data and enhance much-needed research into outcomes and treatment strategies in AFMR.

Effects of uric acid-lowering therapy in patients with essential arterial hypertension

OBJECTIVES

Asymptomatic hyperuricemia (AHU) is elevated serum uric acid (UA) without symptoms. This study aimed to determine the effects of AHU treatment with allopurinol on selected hypertension-mediated organ damage (HMOD) indices in patients with uncomplicated essential arterial hypertension (AH).

METHODS

Patients aged 30-70 years with AHU and AH grade 1-2 with adequate blood pressure (BP) control, without previous urate-lowering therapy (ULT), were divided into two groups: (a) ULT (receiving allopurinol) and (b) control (age- and sex-matched patients without ULT). Both received a UA-lowering diet. BP (office, 24 h and central), echocardiographic parameters, carotid intima-media thickness (IMT) and lab tests [high-sensitivity C-reactive protein (hs-CRP)] were measured at baseline and at 6 months follow-up.

RESULTS

Of 100 participants, 87 (44 ULT, 43 controls) completed the study. At 6 months follow-up, there was a greater reduction in serum UA concentration in the ULT group than in the control group. Patients receiving allopurinol had significant reductions in office systolic and diastolic BP, central systolic BP, pulse pressure, IMT (0.773 ± 0.121 vs. 0.752 ± 0.13 mm, P = 0.044) and hs-CRP (3.36 ± 2.73 vs. 2.74 ± 1.91 mg/L, P = 0.028) compared to controls. Multivariate regression analysis revealed the independent relationship between reduction in IMT and UA lowering (P < 0.026).

CONCLUSION

In patients with AH and AHU, treatment with allopurinol leads to improvement in BP control and reduction in HMOD intensity, in particular IMT. The decrease in hs-CRP concentration associated with ULT may have a beneficial effect on a patient's long-term prognosis.

Evaluating left atrial appendage function in a subtype of non-valvular atrial fibrillation using transesophageal echocardiography combined with two-dimensional speckle tracking

BACKGROUND

The use of transesophageal echocardiography (TEE) is a clinically feasible method for quantitative analysis of left atrial appendage (LAA) function. LAA dysfunction is closely associated with atrial fibrillation (AF)-related stroke. However, there are few studies on the changes in LAA function in patients with different types of AF. This study aimed to observe changes in LAA systolic motion and function in patients with different types of AF by using speckle-tracking echocardiography (STE).

METHODS

A retrospective study of 216 patients with non-valvular AF was conducted. The LAA was divided into three parts: the basal segment (B), middle segment (M), and top segment (A). Speck -racking technology was used to measure and record the forward strain values of the basal segment (B), middle segment (M), and top segment (A) of the LAA, and the peak positive strain dispersion of the LAA was calculated. The left atrial appendage mechanical dispersion (LAAMD) was defined as the standard deviation (SD) of the peak positive strain at each segment of the R-R interval.

RESULTS

Partial speckle-tracking parameters of the LAA showed statistical significance between the two groups. The peak strain on the top segment of the LAA was reduced in the persistent atrial fibrillation (per-AF) group compared to the paroxysmal atrial fibrillation (par-AF) group [11.87 (6.47-20.12) vs. 16.02 (9.76-24.50); 12.66 (6.66-21.22) vs. 20.16 (14.16-30.56); both P<0.01]. In the group with lower LAAMD, the proportion of patients with persistent AF (per-AF) was higher (66.3% vs. 33.7%; P<0.001), the left atrial dilatation was more significant (45.80±5.656 vs. 42.85±4.867; P<0.001), the LAA filling velocity and LAA empty velocity were lower (42.35±20.354 vs. 51.0±20.599; 38.71±24.39 vs. 51.62±21.282; both P<0.001), the LAA ejection fraction was significantly lower (52.16±25.538 vs. 70.85±20.741; P=0.000), and the peak positive strains of the M and A of the LAA were lower than those in the higher LAAMD group.

CONCLUSIONS

The deformability of the LAA is decreased diffusely in per-AF, especially in the A of the LAA. Compliance with LAA was worse in patients with per-AF than in those with par-AF.

Prognostic Impact of Echocardiographic Congestion Grade in HFpEF With and Without Atrial Fibrillation

BACKGROUND

Atrial fibrillation (AF) is common in heart failure with preserved ejection fraction (HFpEF).

OBJECTIVES

This study aimed to investigate the prognostic value of echocardiographic markers of congestion that can be applied to both AF and patients without AF with HFpEF.

METHODS

We conducted a multicenter study of 505 patients with HFpEF admitted to hospitals for acute decompensated heart failure. The ratio of early diastolic transmitral flow velocity to mitral annulus velocity (E/e'), the tricuspid regurgitation peak velocity, and the collapsibility of the inferior vena cava were obtained at discharge. Congestion was determined by echocardiography if any one of E/e' ≥14 (E/e' ≥11 for AF), tricuspid regurgitation peak velocity ≥2.8 m/s, or inferior vena cava collapsibility <50% was positive. We classified patients into grade A, grade B, and grade C according to the number of positive congestion indices. The primary endpoint was the composite of cardiovascular death and heart failure hospitalization.

RESULTS

During the follow-up period (median: 373 days), 162 (32%) patients experienced the primary endpoint. Grade C patients had a higher risk for the primary endpoint than grade A (HR: 2.98; 95% CI: 1.97-4.52) and grade B patients (HR: 1.92; 95% CI: 1.29-2.86) (log-rank P < 0.0001). Echocardiographic congestion grade improved the predictive value when added to the age, sex, New York Heart Association functional class, and N-terminal pro-B-type natriuretic peptide, not only in sinus rhythm (Uno C-statistic: 0.670 vs 0.655) but in AF (Uno C-statistic: 0.667 vs 0.639).

CONCLUSIONS

Echocardiographic congestion grade has prognostic value in patients with HFpEF with and without AF.

Proposal for a clinical and an echocardiographic score for prediction of left atrial thrombosis in atrial fibrillation patients undergoing early electrical cardioversion

AIMS

Left atrial thrombosis (LAT) is usually detected by transesophageal echocardiography (TEE). The aim of the present study was to identify clinical and echocardiographic factors associated with left atrial thrombosis in atrial fibrillation (AF) patients undergoing early electrical cardioversion (ECV) in order to create scores that can predict LAT, in a non-invasive way.

METHODS

A consecutive cohort of patients with persistent AF scheduled for ECV was evaluated by transthoracic echocardiography and TEE. By a logistic regression model, variables significantly associated with LAT were assessed and introduced in predictive models to develop both a clinical and an echocardiographic prediction score for the presence of LAT.

RESULTS

In total, 125 patients [median 71 (range 49-88) years, 60.0% males] were enrolled. Transesophageal echocardiography showed LAT in 35 patients (28%). The clinical variables significantly associated with LAT were previous stroke (OR = 4.17), higher CHA₂ DS₂ -VASc score (OR = 1.93), lower estimated glomerular filtration rate (OR = 0.80), and higher brain natriuretic peptide levels (OR = 1.44). Among echocardiographic parameters, E/e' ratio was directly associated with LAT (OR = 2.25), while an inverse correlation was detected with left ventricular ejection fraction (OR = 0.43) and total global left atrial strain (OR = 0.59). Two prediction scores (clinical and echocardiographic) were developed. The positive predictive values of the clinical and the echocardiographic score were 80% and 100%, respectively, while the negative predictive values were 98% and 94%, respectively. Combined use of the scores reached a positive and negative predictive value of 100%.

CONCLUSIONS

When providing concordant information the two scores are able to correctly identify patients with or without LAT. An external validation is necessary to demonstrate their usefulness in the clinical practice.

The relation between left ventricular systolic function parameters and preceding or prepreceding beat-to-beat distance in patients with atrial fibrillation: an echocardiographic study

We aimed at investigating the relation between left ventricle (LV) systolic parameters and beat-to-beat distances and also whether this relation is different in heart failure with reduced ejection fraction (HFrEF) patients with atrial fibrillation (AF). The relation between peak velocity in left ventricular outflow (V_LVOT), left atrioventricular plane displacement (LAVPD) or peak systolic tissue Doppler velocity of lateral mitral annulus (Lateral S') and preceding beat-to-beat distance (RR₁) or prepreceding beat-to-beat distance (RR₂) were analyzed by linear regression analysis. From this analysis, three parameters were obtained: slope of regression line, constant of regression line, and square of regression coefficient (r²) of linear relation. In the group with HFrEF, the slope and r² values of the regression line showing the relationship between the RR₁ interval and V_LVOT, LAVPD, and Lateral S' values were higher and the constants were lower. In the Kendall rank correlation analysis, the slope, constant, and r² values of the regression analysis between RR₁ interval and V_LVOT or Lateral S' were in significant correlation with LVEF. The r² of V_LVOT-RR₁ analysis, slope of this analysis, and slope of Lateral S'-RR₁ regression line values were mostly predictive for detecting HFrEF. It was concluded that the novel parameters obtained by linear regression analysis between LV systolic function parameters and RR₁ interval, but not RR₂, might be beneficial for evaluating systolic heart failure in patients with AF. They might have potential for future research about the physiopathology of heart and prognosis in patient with AF.

Mechanical concordance between left atrium and left atrial appendage in nonvalvular atrial fibrillation: can it be exploited to avoid transesophageal echocardiography prior to electrical cardioversion during Covid-19 pandemic?

Transesophageal echocardiography (TEE) is the gold standard for assessing left atrial appendage (LAA) mechanic and thrombosis (LAAT); however, TEE is a high-risk procedure for viral transmission during coronavirus disease 2019 (COVID-19) pandemic. We investigated whether deformation indices of left atrium (LA) at transthoracic echocardiography (TTE) correlate with those of LAA assessed by TEE in nonvalvular atrial fibrillation (NVAF) patients undergoing electrical cardioversion (ECV). Consecutive patients with NVAF of ≥ 48 h or unknown duration, who underwent TEE and TTE at our Institution before ECV were retrospectively investigated. Standard echo-Doppler and LA and LAA myocardial strain and strain rate parameters were analyzed. A total of 115 NVAF patients (71.3 ± 8.1 yr/o, 59.1% men) were included: LAAT was diagnosed in 25 (21.7%) patients. Compared to patients without LAAT, those with LAAT had significantly higher CHA₂DS₂-VASc Risk score (4.5 ± 1.4 vs. 3.5 ± 1.1, p < 0.001), and lower ejection fraction (46.0 ± 14.8 vs. 57.6 ± 8.6%, p < 0.001). In LAAT patients, global strain of LA (8.7 ± 2.6 vs. 16.3 ± 4.5%, p < 0.001) and LAA (7.0 ± 1.7 vs. 11.7 ± 2.0%, p < 0.001) was significantly reduced compared to non-LAAT patients. A close relationship between left atrial strain reservoir (LASr) and LAA-global strain was demonstrated (r = 0.81). By univariable analysis, CHA₂DS₂-VASc Risk Score (OR 2.01, 95%CI 1.34–3.00), NT-proBNP (OR 1.36, 95%CI 1.19–1.54), ejection fraction (OR 0.92, 95%CI 0.88–0.96), E/e’ ratio (OR 2.07, 95%CI 1.51–2.85), and LASr (OR 0.39, 95%CI 0.25–0.62) were strongly associated with LAAT presence at TEE. By multivariable analysis, only LASr (OR 0.40, 95%CI 0.24–0.70) retained statistical significance. ROC curve analysis revealed that an LASr cut-off value ≤ 9.3% had 98.9% sensibility and 100% specificity to identify LAAT by TEE (AUC = 0.98). In patients with NVAF of ≥ 48 h or unknown duration, scheduled to undergo ECV, LA deformation assessment by TTE might substitute invasive measurement of LAA function by TEE, simplifying diagnostic approach and possibly contributing to reduce COVID-19 infection diffusion.

Mitral Annular Dynamics in AF Versus Sinus Rhythm: Novel Insights Into the Mechanism of AFMR

OBJECTIVES

This study aimed to investigate mitral annular dynamics in atrial fibrillation (AF) and after sinus rhythm restoration, and to assess the relationship between annular dynamics and mitral regurgitation (MR).

BACKGROUND

AF can be associated with MR that improves after sinus rhythm restoration. Mechanisms underlying this atrial functional MR (AFMR) are ill-understood and generally attributed to left atrial remodeling.

METHODS

Fifty-three patients with persistent AF and normal left ventricular ejection fraction were prospectively examined by means of 3-dimensional transesophageal echocardiography before, immediately after, and 6 weeks after electric cardioversion to sinus rhythm. Annular motion was assessed during AF and in sinus rhythm with the use of 3-dimensional analysis software, and the relationship with MR severity was explored.

RESULTS

During AF and immediately after sinus rhythm restoration, the mitral annulus behaved relatively adynamically, with an overall change in annular area of 10.3% (95% CI: 8.7%-11.8%) and 12.2% (95% CI: 10.6%-13.8%), respectively. At follow-up, a significant increase in annular dynamics (19.0%; 95% CI: 17.4%-20.6%; P < 0.001) was observed, owing predominantly to an increase in presystolic contraction (P < 0.001). The effective regurgitant orifice area decreased from 0.15 cm² (0.10 cm²-0.23 cm²) during AF to 0.09 cm² (0.05 cm²-0.12 cm²) at follow-up (P < 0.001) in the total cohort, and from 0.27 (0.23-0.33) to 0.16 (0.12-0.29) in the subgroup with effective regurgitant orifice area (EROA) ≥0.20 cm². The change in presystolic annular motion was the only independent determinant of the decrease in MR severity (P = 0.027), by optimizing annular-leaflet imbalance. Patients with more pronounced blunting of presystolic dynamics had a higher EROA (P < 0.001), because of a lower total-to-closed leaflet area ratio (P < 0.001) at each point in time. This ratio was the strongest independent determinant of AFMR severity (adjusted P = 0.003).

CONCLUSIONS

Mitral annular dynamics are impaired in AF, with blunted presystolic narrowing that contributes to AFMR. Sinus rhythm restoration allows gradual recovery of presystolic annular dynamics. Improved annular dynamics decrease AFMR severity by optimizing annular-leaflet imbalance, regardless of LA remodeling.

Predictive value of left atrial function for latent paroxysmal atrial fibrillation as the cause of embolic stroke of undetermined source

BACKGROUND

In patients with embolic stroke of undetermined source (ESUS), paroxysmal atrial fibrillation (AF) is often diagnosed, however, the risk of paroxysmal AF in ESUS has not been well described. Several studies have suggested a linkage between left atrial (LA) functional parameters and risk of AF in stroke patients. The aim of this study was to assess the role of LA functional parameters as predictors of latent paroxysmal AF in ESUS on admission.

METHODS

Between January 2015 and December 2019, consecutive stroke patients with suspected ESUS at admission were prospectively included in this study. They were under hospital electrocardiographic monitoring for detection of new-onset AF. Various echocardiographic parameters including left atrial strain were assessed for association with new-onset AF.

RESULTS

We gathered 1082 consecutive patients with ischemic stroke. After exclusions, 121 patients with suspected ESUS at admission formed the study cohort. New-onset AF was detected in 46 (38%) patients during hospital electrocardiographic monitoring (median follow-up: 18 days). LA pump and reservoir strains were significantly and independently associated with new-onset AF. Receiver operating characteristic analysis for the association with new-onset AF showed that the areas under the curve (AUCs) of clinical parameters plus one of each strain (LA pump strain: AUC: 0.86±0.04 and LA reservoir strain: AUC: 0.76±0.05) models were significantly better than plus LA volume index (AUC: 0.68±0.04, compared p-values <0.05).

CONCLUSIONS

LA strain was significantly associated with new development of AF. Patients with impaired LA function at admission should be carefully monitored to find AF.

Improving the diagnosis of heart failure in patients with atrial fibrillation

OBJECTIVE

To improve the echocardiographic assessment of heart failure in patients with atrial fibrillation (AF) by comparing conventional averaging of consecutive beats with an index-beat approach, whereby measurements are taken after two cycles with similar R-R interval.

METHODS

Transthoracic echocardiography was performed using a standardised and blinded protocol in patients enrolled in the RATE-AF (RAte control Therapy Evaluation in permanent Atrial Fibrillation) randomised trial. We compared reproducibility of the index-beat and conventional consecutive-beat methods to calculate left ventricular ejection fraction (LVEF), global longitudinal strain (GLS) and E/e' (mitral E wave max/average diastolic tissue Doppler velocity), and assessed intraoperator/interoperator variability, time efficiency and validity against natriuretic peptides.

RESULTS

160 patients were included, 46% of whom were women, with a median age of 75 years (IQR 69-82) and a median heart rate of 100 beats per minute (IQR 86-112). The index-beat had the lowest within-beat coefficient of variation for LVEF (32%, vs 51% for 5 consecutive beats and 53% for 10 consecutive beats), GLS (26%, vs 43% and 42%) and E/e' (25%, vs 41% and 41%). Intraoperator (n=50) and interoperator (n=18) reproducibility were both superior for index-beats and this method was quicker to perform (p<0.001): 35.4 s to measure E/e' (95% CI 33.1 to 37.8) compared with 44.7 s for 5-beat (95% CI 41.8 to 47.5) and 98.1 s for 10-beat (95% CI 91.7 to 104.4) analyses. Using a single index-beat did not compromise the association of LVEF, GLS or E/e' with natriuretic peptide levels.

CONCLUSIONS

Compared with averaging of multiple beats in patients with AF, the index-beat approach improves reproducibility and saves time without a negative impact on validity, potentially improving the diagnosis and classification of heart failure in patients with AF.

Left Atrial Strain Associated with Functional Recovery in Patients Receiving Optimal Treatment for Heart Failure

BACKGROUND

Heart failure with recovered ejection fraction (HFrecEF) has been reported in several previous studies to have a better prognosis than heart failure with reduced ejection fraction (HFrEF). However, the factors associated with HFrecEF have not been identified. The aim of this study was to test the hypothesis that left atrial (LA) strain could help identify patients with recovered ejection fraction (EF) among those with heart failure (HF) with low EF on admission.

METHODS

One hundred consecutive patients hospitalized for the first time for new-onset HF were enrolled. Patients were clinically diagnosed with HFrEF on admission (left ventricular EF < 40%) and received optimal treatment for HF. Twenty-eight patients improved to HFrecEF during 6 months of follow-up.

RESULTS

Regarding clinical background, there were significantly more women and a lower rate of atrial fibrillation in the HFrecEF group than in the HFrEF group. In a multivariate logistic regression analysis, LA strain was an independent predictor of HFrecEF, even after adjustment for gender and left ventricular EF (odds ratio: 4.06; 95% CI: 2.04-8.07; P < .001). A cutoff value of 10.8% for LA strain showed high sensitivity (96%) and specificity (82%) in identifying HFrecEF in patients with HF presenting with low EF on admission. During a follow-up period of 24 ± 13 months, 31 patients (31%) had cardiovascular death or readmission for HF. Patients with reduced LA strain (<10.8%) had significantly shorter event-free survival than those with preserved LA strain (P = .02).

CONCLUSIONS

LA strain is a useful indicator for predicting HFrecEF and should be considered as a routine measurement in patients with HFrEF on admission.

Incremental prognostic role of left atrial reservoir strain in asymptomatic patients with moderate aortic stenosis

Left atrial (LA) mechanics assessed by two-dimensional speckle tracking echocardiography (2D-STE) have not been extensively studied and clearly characterized in patients with moderate aortic stenosis (AS). Accordingly, we aimed to evaluate the usefulness of LA reservoir strain for risk stratification of asymptomatic patients with moderate AS. This retrospective study included all consecutive asymptomatic patients with moderate AS who underwent transthoracic echocardiography implemented with 2D-STE analysis of LA myocardial strain and strain rate indices at our Institution, between February 2011 and September 2019. During the follow-up period, we evaluated the occurrence of any of the following: (1) CV hospitalization; (2) The recourse to AS surgery; (3) Cardiac death or sudden death. A total of 186 patients (mean age 71.9 ± 12.7 years, 61.8% men) were included in the present study. During a mean follow-up of 2.3 ± 1.9 years, no patients died and 63 adverse CV events were recorded: 48 patients were hospitalized because of heart failure (28 patients), acute coronary syndrome (10 patients), arrhythmias (10 patients) and 15 patients underwent AS surgery. At the multivariate Cox regression analysis, type 2 diabetes mellitus (OR 1.87, 95%CI 1.05-3.34, p = 0.03), NT-proBNP (OR average 1.14, 95%CI 1.02-1.27, p = 0.02), average E/e' ratio (OR 1.07, 95%CI 1.01-1.15, p = 0.04) and most of all left atrial positive global strain (LA-GSA+) (OR 0.85, 95%CI 0.81-0.90, p < 0.0001) were independently associated with the outcome. LA-GSA+ (optimal cut-off ≤ 19%, AUC = 0.94, 87% sensitivity, 99% specificity, positive predictive value 99%, negative predictive value 88%) showed the highest diagnostic performance. An impaired LA reservoir strain can contribute to identify a subset of asymptomatic patients with moderate AS at higher risk, who may benefit from closer echocardiographic follow-up and/or early surgery.

Cardiac Imaging to Assess Left Ventricular Systolic Function in Atrial Fibrillation

The validity and reproducibility of systolic function assessment in patients with atrial fibrillation (AF) using cardiac magnetic resonance, echocardiography, nuclear imaging and computed tomography is unknown. A prospectively-registered systematic review was performed, including 24 published studies with patients in AF at the time of imaging and reporting validity or reproducibility data on left ventricular systolic parameters (PROSPERO: CRD42018091674). Data extraction and risk of bias were performed by 2 investigators independently and synthesized qualitatively. In 3 cardiac magnetic resonance studies (40 AF patients), left ventricular ejection fraction and stroke volume measurements correlated highly with catheter angiography (r ≥0.85), and intra- and/or interobserver variability were low. From 3 nuclear studies (171 AF patients), there were no external validation assessments but intra and/or interobserver and intersession variability were low. In 18 echocardiography studies (2,566 AF patients), 2 studies showed high external validity of global longitudinal strain and tissue Doppler s' with angiography-derived dP/dt (r ≥0.88). Global longitudinal strain and myocardial performance index were both associated with adverse cardiovascular events. Reproducibility of echocardiography was better when selecting an index-beat (where 2 preceding R-to-R intervals are similar) compared to averaging of consecutive beats. There were no studies relating to computed tomography. Most studies were small and biased by selection of patients with good quality images, limiting clinical extrapolation of results. The validity of systolic function measurements in patients with AF remains unclear due to the paucity of good-quality data.

Comparison of left atrial and left atrial appendage mechanics in the risk stratification of stroke in patients with atrial fibrillation

Background

Left atrial (LA) and left atrial appendage (LAA) dysfunction has been demonstrated to contribute to atrial fibrillation (AF)-related stroke. However, usefulness of LA and LAA mechanics has not been fully compared. We sought to investigate the association of LA and LAA mechanics with stroke and to compare their diagnostic values in the risk stratification of stroke in patients with nonvalvular AF.

Methods

A total of 208 consecutive patients with AF (63.58 ± 10.37 years, 63.9% male,57.7% persistent AF) who underwent echocardiography before catheter ablation were prospectively enrolled. Speckle-tracking was used to measure LA and LAA global longitudinal strain (GLS). LA and LAA mechanical dispersions (MD) were defined as the standard deviation (SD) of time to peak positive strain corrected by the R-R interval.

Results

Patients with prior stroke/ transient ischemic attack (TIA) (n = 31) had significantly higher LA and LAA MD than those without (n = 177) (11.56 ± 4.38% vs. 8.43 ± 3.44%, 15.15 ± 5.46% vs. 10.94 ± 4.40%, both P < 0.01). In multivariable analysis, LA and LAA MD were independently associated with stroke/TIA (odds ratio, 1.18–1.29, 1.19–1.22, respectively, both P < 0.01), providing incremental values over clinical and standard echocardiographic parameters. In a subgroup analysis, LA MD was more useful than LAA MD in patients with normal LA volumes, while LAA MD was superior to LA MD in patients with LA enlargement.

Conclusions

Higher LA and LAA mechanical dispersion are independently associated with stroke/TIA in AF patients and had incremental values over clinical and conventional echocardiographic parameters. What’s more, priorities of dispersion assessment are different depending on patients’ LA size.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12947-020-00232-z.

Incremental diagnostic role of left atrial strain analysis in thrombotic risk assessment of nonvalvular atrial fibrillation patients planned for electrical cardioversion

During the COVID-19 pandemic, transesophageal echocardiography (TEE) for left atrial appendage thrombosis (LAAT) detection should be limited to situations of absolute necessity. We sought to identify the main conventional and functional echocardiographic parameters associated with LAAT on TEE in non-valvular atrial fibrillation (NVAF) patients planned for electrical cardioversion (ECV). This retrospective study included 125 consecutive NVAF patients (71.5±7.8 yrs, 75 males), who underwent TEE at our Institution between April 2016 and January 2020, to exclude LAAT before scheduled ECV. All patients underwent a transthoracic echocardiography (TTE) implemented with speckle tracking echocardiography (STE) analysis of left atrial (LA) strain and strain rate (SR) parameters. 28% of patients were diagnosed with LAAT, while 72% without LAAT. Compared to controls, patients with LAAT had significantly higher CHA₂DS₂-Vasc Score and average E/e’ ratio, and significantly lower left ventricular ejection fraction (LVEF). Moreover, LA-peak positive global atrial strain (GSA+) and LA-SR parameters were significantly reduced in patients with LAAT. Multivariate logistic regression revealed that, differently from CHA₂DS₂-Vasc Score, LVEF (OR 0.88, 95%CI 0.81–0.97, p = 0.01), average E/e’ ratio (OR 2.36, 95%CI 1.41–3.98, p = 0.001), and LA-GSA+ (OR 0.57, 95%CI 0.36-0-90, p = 0.01) were independently associated with LAAT. LA-GSA+ (optimal cut-off ≤ 9.1%, AUC 0.95) showed the highest diagnostic performance. Finally, a strong linear correlation of LA peak-to-peak SR with both LA appendage filling (r = 0.86) and emptying (r = 0.83) velocities was demonstrated. TTE implemented with STE analysis of LA mechanics improves thrombotic risk assessment of NVAF patients.

Global Left Atrial Longitudinal Strain Using 3-Beat Method Improves Risk Prediction of Stroke Over Conventional Echocardiography in Atrial Fibrillation

Background:

Atrial fibrillation (AF) is associated with a risk of ischemic stroke, and functional myocardial imaging has offered novel insights on its pathophysiology and prognosis, but its use in AF-related stroke remains limited. We aimed to evaluate the feasibility of left atrial (LA) deformations and its prognostic values of ischemic stroke in a large-scale AF population.

Methods:

Peak atrial longitudinal strain (LA strain), left ventricular strain (global longitudinal strain), LA strain rate (LA SR) at reservoir (LA longitudinal systolic strain rate), and early diastolic conduit (LA longitudinal early diastolic strain rate) phases were analyzed using 2-dimensional speckle tracking echocardiography. Consecutive 3-beat averaged values of strain and SR were used. The clinical end point was ischemic stroke.

Results:

Among 1457 AF participants, the mean LA strain, LA longitudinal systolic strain rate, and LA longitudinal early diastolic strain rate values were 12.9±4.8%, 0.80±0.28 s − 1 , and −1.17±0.46 s − 1 , respectively. There were strong positive linear relationships of 3-beat average with index-beat analysis (R=0.94, 0.94, and 0.94 for LA strain, LA longitudinal systolic strain rate, and LA longitudinal early diastolic strain rate, respectively; all P <0.001). Multivariate Cox regression models incorporating conventional echocardiography parameters demonstrated LA strain and SRs to be independent prognosticators of ischemic stroke during a median follow-up of 37.6 months. Utilization of LA strain further provided incremental value over CHA 2 DS 2 -VASc scoring ( C statistics, 0.78–0.81; P =0.006) for ischemic stroke. Overall, the prognostic performances of LA deformations were attenuated after adding global longitudinal strains in models.

Conclusions:

LA deformations by the 3-beat method are feasible and reproducible during AF. LA strain provided additional prognostic implication over clinical information and conventional echocardiographic measures for ischemic stroke in the AF population but not incremental to global longitudinal strains.

Left atrial diameter and atrial fibrillation, but not elevated NT-proBNP, predict the development of pulmonary hypertension in patients with HFpEF

BACKGROUND

The determinants of pulmonary hypertension (PH) due to heart failure with preserved ejection fraction (HFpEF) have been poorly investigated in patients with cardiovascular diseases (CVD).

METHODS

From July 1 2017 to March 31 2019, a total of 149 consecutive HFpEF patients hospitalized with CVD were enrolled in this prospective cross-sectional study. A systolic pulmonary artery pressure (PASP) > 35 mmHg estimated by echocardiography was defined as PH-HFpEF. Logistic regression was performed to establish predictors of PH in HFpEF patients.

RESULTS

Overall, the mean age of participants was 72 ± 11 years, and 74 (49.7%) patients were females. A total of 59 (39.6%) patients were diagnosed with PH-HFpEF by echocardiography. The left atrial diameter (LAD) was related to the ratio of the transmitral flow velocities/mitral annulus tissue velocities in early diastole (E/E') and the left ventricular diameter in systole (LVDs). N-Terminal pro B-type natriuretic peptide (NT-proBNP) was not found to be associated with LAD and impaired diastolic or systolic function of the left ventricle. Multivariable logistic regression showed that atrial fibrillation (AF) increased the risk of PH-HFpEF incidence 3.46-fold with a 95% confidence interval (CI) of 1.44-8.32, P = 0.005. Meanwhile, LAD ≥ 45 mm resulted in a 3.43-fold increased risk, 95% CI: 1.51-7.75, P = 0.003. However, the significance levels of NT-proBNP, age and LVEF were underpowered in the regression model. Two variables, AF and LAD ≥ 45 mm, predicted the PH-HFpEF incidence (C-statistic = 0.773, 95% CI: 0.695-0.852, P < 0.001).

CONCLUSIONS

Two parameters associated with electrical and anatomical remodelling of the left atrium were related to the incidence of PH in HFpEF patients with CVD.

Atrial functional mitral regurgitation: mechanisms and surgical implications

The term atrial functional mitral regurgitation refers to a newly recognized disease entity in which mitral regurgitation occurs secondary to left atrial disease, without left ventricular dilatation and intrinsic mitral valve disease, typically in the setting of long-standing atrial fibrillation. Recent evidence suggests that atrial functional mitral regurgitation is associated with increased risk of death and heart failure re-hospitalization. The etiology, pathophysiology, and mechanism of atrial functional mitral regurgitation is not completely understood but they should not be regarded as the same as for the conventional type of functional mitral regurgitation secondary to left ventricular dilatation and dysfunction. Mitral annular dilatation, atriogenic leaflet distortion, insufficient leaflet remodeling, and subtle left ventricular dysfunction may play a role in the pathogenesis of atrial functional mitral regurgitation. The therapeutic and surgical considerations of atrial functional mitral regurgitation are different from those of ventricular functional mitral regurgitation. In this review, we assess current evidence regarding this new disease entity and propose a new surgical approach based on up-to-date understanding and experience of this condition.

Prognostic assessment of relative apical sparing pattern of longitudinal strain for severe aortic valve stenosis

Backgrounds

The relative apical sparing pattern (RASP) of left ventricular (LV) longitudinal strain (LS) is frequently associated with cardiac amyloidosis. Elderly patients with aortic valve stenosis (AS) complicated by transthyretin amyloid cardiomyopathy have poor prognosis. Furthermore, deteriorated basal LS in AS patients has been reported to be associated with adverse outcome. We investigated the association between RASP and outcomes in patients with severe AS.

Methods

We retrospectively studied 156 consecutive patients with severe AS and preserved LV ejection fraction. RASP was assessed by both of semi-quantitative (sRASP) and quantitative (qRASP) methods. sRASP was defined as a deterioration of LS (≥-10%) in ≥ 5 (of 6) basal segments, relative to preserved LS (<-15%) in at least 1 apical segment. qRASP was calculated using the following formula: average apical LS/(average basal LS + average mid-ventricle LS); qRASP ≥ 1 was defined as positive. Patients were followed up to determine outcomes, which included sudden cardiac death or unexpected admission due to heart failure, over a median of 1.9 years.

Results

sRASP and qRASP were assessed in all patients, but 24 and 42 patients fulfilled the criteria for sRASP and qRASP, respectively. Both assessments were significantly associated with outcomes (n = 44; 28%). Furthermore, sRASP was significantly associated with outcome after adjusting for EuroSCORE, NYHA ≥ II, or global longitudinal strain. A model based on these covariates for predicting outcomes significantly improved by adding sRASP.

Conclusion

RASP is observed in some patients with severe AS and provides additive prognostic information over conventional parameters.

Preprocedural restoration of sinus rhythm and left atrial strain predict outcomes of catheter ablation for long-standing persistent atrial fibrillation

INTRODUCTION

Catheter ablation (CA) for long-standing persistent atrial fibrillation (LS-AF) remains challenging. We aimed to explore whether sinus rhythm (SR) restoration and left atrium (LA) function after pretreatment with antiarrhythmic drugs (AAD's) and electrical cardioversion (ECV) predict procedural outcomes.

METHODS AND RESULTS

We included 100 consecutive patients with LS-AF who were treated with AAD/ECV for at least 3 months before CA. The echocardiographic LA strain during reservoir phase (LASr) was assessed after pretreatment as a marker of LA fibrosis. The recurrence was recorded for ≥1 year after the last procedure. During a 34 ± 16-month follow-up period, the single and multiple procedures and pharmaceutically assisted success rates were 40% and 71%, respectively. Patients with preprocedural SR restoration and higher LASr showed a significantly higher recurrence-free probability after the last CA (logrank P = .001 and P < .001, respectively). Failure of preprocedural SR restoration and LASr ≤8.6% were independently associated with recurrence after the last CA (hazard ratio [HR]: 3.13, 95% confidence interval [CI]: 1.42-6.91, P = .005; HR: 3.89, 95% CI: 1.65-9.17, P = .002, respectively). These parameters added incrementally to the predictive value of AF duration and LA dilatation (P = .03 and P = .002, respectively) and improved the recurrence-risk stratification (net reclassification improvement = 0.39; 95% CI = 0.13-0.65; P = .003).

CONCLUSION

In patients with LS-AF, the inability to restore SR and lower LASr after AAD/ECV treatment independently and incrementally predicts the recurrence after CA. These findings might be useful for determining LS-AF ablation candidates.

Myocardial performance index by tissue Doppler echocardiography predicts adverse events in patients with atrial fibrillation

AIMS

The prognostic value of myocardial performance index (MPI) has not yet been assessed in patients with atrial fibrillation (AF). The aim of this study was to evaluate the prognostic value of MPI by tissue Doppler imaging (TDI) M-mode in AF patients.

METHODS AND RESULTS

Echocardiograms from 210 patients with AF during examination were analysed offline. Patients with known heart failure (HF) were excluded. Time intervals were measured using an M-mode line through the mitral valve leaflets to provide a colour diagram of the mitral leaflet movement so all time intervals could be measured from one cardiac cycle. MPI was calculated as the sum of isovolumic relaxation time and isovolumic contraction time divided by the ejection time [(IVRT+IVCT)/ET]. During a median follow-up of 2.4 years, 84 patients (40%) reached the combined endpoint of major adverse cardiovascular events (MACE), being all-cause mortality, HF, myocardial infarction, or stroke. Increasing MPI was significantly associated with an increased risk of MACE, and the risk increased with 20% per 0.1 increase in MPI [hazard ratio (HR) 1.20, 95% confidence interval (CI) 1.10-1.32; P < 0.001]. Increasing MPI was also significantly associated with a lower left ventricular ejection fraction (LVEF) (P < 0.001). Nevertheless, MPI remained an independent predictor even after adjustment for age, sex, diabetes mellitus, left atrial volume, and LVEF (HR 1.12, 95% CI 1.01-1.25; P = 0.038).

CONCLUSION

Increasing MPI was significantly associated with increased risk of MACE and remained an independent predictor after multivariable adjustment. This demonstrates that the MPI obtained by TDI M-mode might be useful in assessing cardiac function in AF patients with ongoing arrhythmia during examination.

Value of Index Beat in Evaluating Left Ventricular Systolic and Diastolic Function in Patients with Atrial Fibrillation: A Dual Pulsed-Wave Doppler Study

Atrial fibrillation (AF) poses challenges in use of the echocardiogram to assess left ventricular (LV) function. The index beat method has been found to agree well with the average method. We aimed to assess the value of the index beat method in evaluation of LV function using the dual pulsed wave Doppler technique. Peak early diastolic mitral inflow velocity (E) and diastolic (e') and systolic (s') mitral annulus velocity were simultaneously obtained and measured beat-to-beat in patients with AF. The index beat s' exhibited the best correlation (r = 0.96 and 0.92, respectively, for septal and lateral wall, both p values = 0.000) with the mean, while E/e' at the pre-index beat, rather than at the index beat-initiated cycle, had the best correlation with the mean (r = 0.88 for septal and 0.97 for lateral wall, both p values = 0.000).

Association Between Right Ventricular Contractile Function and Cardiac Events in Isolated Postcapillary and Combined Pre- and Postcapillary Pulmonary Hypertension

BACKGROUND

Recent studies have shown that patients with combined pre- and postcapillary pulmonary hypertension (CpcPH) had worse outcomes than those with isolated postcapillary pulmonary hypertension (IpcPH). However, the prognostic factors including right ventricular (RV) function have not been well documented. The aim of this study was to assess the differentiation of PH phenotypes, using echocardiography, and the association between RV longitudinal strain and cardiac events.

METHODS AND RESULTS

We prospectively recruited consecutive patients who had undergone right heart catheterization. The primary endpoint was cardiovascular death or readmission due to heart failure. We included 137 patients with Group 2 PH. A RV longitudinal strain of 17% was sensitive (85%) and specific (70%) to determine the CpcPH. During a median period of 31 months, 43 patients experienced the primary endpoint during follow-up. In a multivariate analysis, RV longitudinal strain was associated with the primary endpoint in both CpcPH and IpcPH (HR: 0.84, P = 0.003; HR: 0.86, P = 0.001).

CONCLUSIONS

Lower RV longitudinal strain was independently associated with worse outcomes in CpcPH and IpcPH. RV longitudinal strain may play a prognostic role in PH phenotypes.

Ratio of Early Mitral Inflow Velocity to the Global Diastolic Strain Rate and Global Left Ventricular Longitudinal Systolic Strain Predict Overall Mortality and Major Adverse Cardiovascular Events in Hemodialysis Patients

Background

The ratio of early mitral inflow velocity to the global diastolic strain rate (E/E'sr) and global longitudinal systolic strain (GLS) of the left ventricle (LV) are emerging indices of diastolic and systolic functions, respectively, for the LV. Their prognostic significance in the prediction of mortality and cardiovascular (CV) outcomes remains underexplored in hemodialysis (HD) patients.

Methods

This prospective study included 190 maintenance HD patients. The E/E'sr ratio and GLS were assessed using two-dimensional speckle tracking echocardiography. The clinical outcomes included overall mortality, CV mortality, and major adverse cardiovascular events (MACE). The associations between the E/E'sr ratio, GLS, and clinical outcomes were evaluated using multivariate Cox regression analysis. The incremental values of the E/E'sr ratio and GLS in outcome prediction were assessed by χ ² changes in Cox models.

Results

Over a median follow-up period of 3.7 years, there were 35 overall deaths, 16 CV deaths, and 45 MACE. Impaired diastolic function with a higher E/E'sr ratio was associated with overall mortality (HR, 1.484; 95% CI, 1.201-1.834; p < 0.001), CV mortality (HR, 1.584; 95% CI, 1.058-2.371; p = 0.025), and MACE (HR, 1.205; 95% CI, 1.040-1.397; p = 0.013) in multivariate adjusted Cox analysis. Worsening GLS was associated with overall mortality (HR, 1.276; 95% CI, 1.101-1.480; p = 0.001), CV mortality (HR, 1.513; 95% CI, 1.088-2.104; p = 0.014), and MACE (HR, 1.214; 95% CI, 1.103-1.337; p < 0.001). The E/E'sr ratio and GLS had better outcome prediction than the E to early diastolic mitral annular velocity (E/E') ratio and left ventricular ejection fraction (LVEF). Moreover, adding the E/E'sr ratio and GLS to Cox models containing relevant clinical and conventional echocardiographic parameters improved the prediction of overall mortality (p < 0.001), CV mortality (p < 0.001), and MACE (p < 0.001).

Conclusion

The E/E'sr ratio and GLS, as emerging indices of LV diastolic and systolic functions, significantly predict mortality and CV outcomes and outperform conventional echocardiographic parameters in outcome prediction in HD patients.

Early Impairment Left Ventricular Mechanics in Children With Mitral Valve Prolapse

Early impairment of left ventricular (LV) function has been reported in some inherited connective tissue diseases such as Marfan syndrome or rheumatic heart disease in pediatric patients. However, there is no study about cardiac strain in pediatric patients with primary mitral valve prolapse (MVP). The aim of this study was to evaluate the LV functions in pediatric patients with primary MVP, mild or moderate mitral regurgitation (MR), and normal LV ejection fraction. The study group included 72 consecutive patients (40 female, mean age: 13.1 ± 5.2 with primary MVP who had mild or moderate MR, and normal systolic function (LV ejection fraction ≥60%) were compared with 40 healthy children using conventional echocardiography, tissue Doppler imaging, and 2-dimensional speckle tracking echocardiography. Patients were divided into subgroups according to the MR severity: mild (n:34), and moderate (n:38) and leaflet thickness: classical (n: 40), and nonclassical (n: 32). The children with MR had significantly lower values for global early diastolic strain rate ([SRe] patients: 1.40 ± 0.25 vs controls: 1.62 ± 0.54; p = 0.001), and E/SRe (patients: 72.7 ± 5.6 vs controls: 62.1 ± 4.9; p <0.04) when compared with the control group. In subgroup analysis, SRe (mild: 1.49 ± 0.38 vs moderate: 1.32 ± 0.31; p <0.001) was lower in MVP patients with moderate MR compared to mild MR, and E/SRe (mild: 69.4 ± 5.1 vs moderate: 75.1 ± 6.4; p <0.001) value was higher in MVP patients with moderate MR compared to mild MR. Diatolic strain parameters, SRe, and E/SRe are more sensitive markers of early subtle myocardial injury in pediatric patients with primary MVP.

Practical tips and tricks in measuring strain, strain rate and twist for the left and right ventricles

Strain imaging provides an accessible, feasible and non-invasive technique to assess cardiac mechanics. Speckle tracking echocardiography (STE) is the primary modality with the utility for detection of subclinical ventricular dysfunction. Investigation and adoption of this technique has increased significantly in both the research and clinical environment. It is therefore important to provide information to guide the sonographer on the production of valid and reproducible data. The focus of this review is to (1) describe cardiac physiology and mechanics relevant to strain imaging, (2) discuss the concepts of strain imaging and STE and (3) provide a practical guide for the investigation and interpretation of cardiac mechanics using STE.

Mitral Annular and Left Ventricular Dynamics in Atrial Functional Mitral Regurgitation: A Three-Dimensional and Speckle-Tracking Echocardiographic Study

BACKGROUND

Patients with atrial fibrillation (AF) and left atrial (LA) enlargement may develop functional, normal leaflet motion mitral regurgitation (MR) without left ventricular (LV) remodeling. Mitral annular dynamics and LV mechanics are important for preserving normal mitral valve function. The aim of this study was to assess the annular and LV dynamics in patients with AF and functional MR.

METHODS

Twenty-one patients with AF with moderate or more MR (AFMR+ group), 46 matched patients with AF with no or mild MR (AFMR- group), and 19 normal patients were retrospectively studied. Mitral annular dynamics were quantitatively assessed using three-dimensional echocardiography. Systolic LV global longitudinal strain (GLS), global circumferential strain, and LA strain were measured using two-dimensional speckle-tracking echocardiography.

RESULTS

The normal annulus displayed presystolic followed by systolic contraction and increase in saddle shape (P < .01 for all). Presystolic annular dynamics were abolished in both groups of patients with AF (P > .05 vs normal). In contrast, systolic and total annular dynamics during the cardiac cycle were preserved in AFMR- patients (P > .10 vs normal) but impaired in AFMR+ patients (P < .05 vs normal and AFMR-). LV GLS (P < .0001) and LA strain (P = .02), but not LV global circumferential strain (P = .97), were impaired in AFMR+ compared with AFMR- patients despite comparable LA and LV volumes. MR severity correlated with systolic annular contraction (r = 0.64, P < .0001), saddle deepening (r = 0.53, P = .003), and LV GLS (r = 0.46, P < .0001). Multivariate analysis identified that impaired systolic contraction (odds ratio, 2.18; P = .001) and saddle deepening (odds ratio, 2.68; P = .04) were independently associated with MR. Excluding annular dynamics from the model, less negative LV GLS, but not LA strain, became associated with MR (odds ratio, 1.93; P < .0001).

CONCLUSIONS

In patients with AF and absent LA contraction, the normal predominantly "atriogenic" annular dynamics become "ventriculogenic." Isolated LA enlargement is insufficient to cause important MR without coexisting abnormal LV mechanics and annular dynamics during systole. "Atrial" functional MR may not be purely an atrial disorder.

Is echocardiography valid and reproducible in patients with atrial fibrillation? A systematic review

Aims

Echocardiography is vital in the routine assessment and management of atrial fibrillation (AF). We performed a systematic review of the validity and reproducibility of echocardiographic left ventricular systolic and diastolic function in AF, and optimal acquisition methods.

Methods and results

Online databases were searched for studies in patients with AF at the time of echocardiography (1960 to August 2015), prospectively registered with PROSPERO (CRD42015025297). The systematic review included 32 studies from 3 066 search results (1 968 patients with AF). Average age was 67 years, 33% were women, mean LVEF 53% (±10%), and average E/e’ 11.7 (±2.7). Data on the validity and reproducibility of systolic indices were extremely limited. In contrast, diastolic parameters demonstrated correlation with invasive filling pressure and adequate reproducibility: E/e’ (n = 444) r = 0.47 to 0.79; IVRT (n = 177) r = –0.70 to –0.95; E/Vp` (n = 55) r = 0.63 and 0.65; pulmonary vein diastolic flow (n = 67) r = –0.80 and –0.91. Elevated E/e’ (>15) was associated with functional capacity, quality of life, and impaired prognosis. For optimal acquisition in AF patients, cardiac cycles with controlled heart rate (<100 beats/min) and similar preceding and pre-preceding RR intervals are required. Cardiac cycle length and equivalence were more important than the number of beats averaged.

Conclusion

With careful selection of appropriate cardiac cycles, echocardiography is a valid tool to identify diastolic dysfunction in AF, and E/e’ is an independent marker of clinical status and adverse prognosis. However, data on systolic function was extremely limited and requires further prospective study and assessment of variability in clinical practice.

Left Ventricular Systolic Function Assessed by Global Longitudinal Strain is Impaired in Atrial Fibrillation Compared to Sinus Rhythm

Background

Atrial fibrillation (AF) is the most common aberrant cardiac arrhythmia. Many AF patients present with symptoms of dyspnea and fatigue, but have normal left ventricular ejection fraction (LVEF).

Purpose

To determine the reproducibility of measurements of global longitudinal strain (GLS) and strain rate in patients with AF and examine if the arrhythmia is associated with abnormal LV strain and strain rate independent of age, sex, heart rate, LVEF and LV mass. We hypothesized that AF independently reduces ventricular systolic performance.

Methods

The study was conducted as a retrospective analysis of images from 150 randomly selected patients with AF compared to an equal number of subjects with sinus rhythm (SR) matched for age, sex, heart rate, LVEF and LV mass. Half of the patients had normal LVEF (LVEF > 50%) and half had reduced LVEF (LVEF < 50%). GLS and strain rate were measured in each group, as were quantitative LV volumes and standard systolic and diastolic parameters. Results: GLS was significantly impaired in patients with AF compared to subjects with SR, both in the overall population (-12.25 ± 4.1% vs. -16.13 ± 4.7%, p<0.0001), in patients with normal LVEF (-14.41 ± 3.9% vs. -19.42 ± 3.1%, p<0.0001) and in patients with reduced LVEF (-10.10 ± 3.1% vs. -12.85 ± 3.5%, p<0.0001).Linear regression and Bland Altman analyses demonstrated good intraobserver and interobserver agreement for measurements of GLS and strain rate parameters even in patients with AF.

Association between left atrial function assessed by speckle-tracking echocardiography and the presence of left atrial appendage thrombus in patients with atrial fibrillation

Objective:

The aim of the study was to investigate whether the deformation of left atrium (LA) measured by speckle-tracking analysis (STE) is associated with the presence of LA appendage thrombus (LAAT) during non-valvular atrial fibrillation (AF).

Methods:

Eighty-seven patients (mean age 67 years, 59% men) were included to retrospective cross-sectional study. On top of standard echocardiography we assessed: LA longitudinal systolic strain (LS), systolic (LSSR) and early diastolic strain rate (LESR) in four-chamber and two-chamber apical views. All patients underwent transesophageal echocardiography disclosing LAAT in 36 (41%) patients.

Results:

Subgroups with and without thrombi did not differ with regard to clinical characteristics. Univariate factors associated with LAAT were as follows: CH₂ADS₂-VASc Score, left ventricular ejection fraction (LVEF), LV mass, and STE measurements. In a multivariate model only LVEF (p=0.002), LS (p=0.02), LESR (p=0.008), and LSSR (p=0.045) were independently associated with LAAT presence. Moreover, LVEF and LA STE measurements provided incremental value over the CH₂ADS₂-VASc Score.

Conclusion:

Speckle-tracking TTE may be used to describe LA reservoir and conduit function during AF, allowing the identification of patients with higher risk of LAAT and providing incremental value over the CH₂ADS₂-VASc Score.

Three-Dimensional Echocardiographic Assessment of Left Heart Chamber Size and Function with Fully Automated Quantification Software in Patients with Atrial Fibrillation

BACKGROUND

Echocardiographic determination of left heart chamber volumetric parameters by using manual tracings during multiple beats is tedious in atrial fibrillation (AF). The aim of this study was to determine the usefulness of fully automated left chamber quantification software with single-beat three-dimensional transthoracic echocardiographic data sets in patients with AF.

METHODS

Single-beat full-volume three-dimensional transthoracic echocardiographic data sets were prospectively acquired during consecutive multiple cardiac beats (≥10 beats) in 88 patients with AF. In protocol 1, left ventricular volumes, left ventricular ejection fraction, and maximal left atrial volume were validated using automated quantification against the manual tracing method in identical beats in 10 patients. In protocol 2, automated quantification-derived averaged values from multiple beats were compared with the corresponding values obtained from the indexed beat in all patients.

RESULTS

Excellent correlations of left chamber parameters between automated quantification and the manual method were observed (r = 0.88-0.98) in protocol 1. The time required for the analysis with the automated quantification method (5 min) was significantly less compared with the manual method (27 min) (P < .0001). In protocol 2, there were excellent linear correlations between the averaged left chamber parameters and the corresponding values obtained from the indexed beat (r = 0.94-0.99), and test-retest variability of left chamber parameters was low (3.5%-4.8%).

CONCLUSIONS

Three-dimensional transthoracic echocardiography with fully automated quantification software is a rapid and reliable way to measure averaged values of left heart chamber parameters during multiple consecutive beats. Thus, it is a potential new approach for left chamber quantification in patients with AF in daily routine practice.