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

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

Left atrial dysfunction in bicuspid aortic valve patients with severe aortic stenosis is associated with post-operative atrial fibrillation following aortic valve replacement

Aims

To investigate (i) the association between pre-operative left atrial (LA) reservoir strain and post-operative atrial fibrillation (AF) and (ii) the incidence of post-operative ischaemic stroke events separately in bicuspid aortic valve (BAV) and tricuspid aortic valve (TAV) patients after surgical aortic valve replacement for isolated severe aortic stenosis (AS).

Methods and results

We prospectively enrolled 227 patients (n = 133 BAV and n = 94 TAV) with isolated severe AS scheduled for aortic valve replacement. A comprehensive intra- and inter-observer validated pre-operative echocardiogram with an analysis of LA reservoir strain was performed. Post-operative AF was defined as a sustained (>30 s) episode of AF or atrial flutter. The timing of neurological events was defined in accordance with the Valve Academic Research Consortium-3 criteria for stroke. Post-operative AF occurred in 114 of 227 patients (50.2%), with no difference between BAV and TAV patients (48.1 vs. 53.1%, P = 0.452). Persisting post-operative AF at discharge was more frequent in BAV patients (29.7 vs. 8.0%, P = 0.005). Pre-operative LA reservoir strain was independently associated with post-operative AF (odds ratio = 1.064, 95% confidence interval 1.032-1.095, P < 0.001), with a significant interaction between LA reservoir strain and aortic valve morphology (Pinteraction = 0.002). The cumulative transient ischemic attack (TIA)/stroke incidence during follow-up was significantly higher in BAV patients (19.1 vs. 5.8% at 5 years).

Conclusion

Pre-operative LA function was associated with post-operative AF after aortic valve replacement in BAV AS patients, while post-operative AF in TAV AS patients likely depends on transient post-operative alterations and traditional cardiovascular risk factors. TIA/stroke during follow-up was more common in BAV AS patients.

Postoperative evaluation of left atrial stiffness in patients with congenital heart diseases

Left atrial (LA) stiffness is one of the most important factors involved in LA remodeling. LA stiffness has rarely been studied postoperatively in patients with congenital heart diseases (CHDs). This study aimed to evaluate LA stiffness in CHD patients postoperatively. Seventy-five patients (CHDs, 67; controls, 8; age range, 10-41 years) who underwent cardiac catheterization at our institution were included in this study. From the pulmonary artery wedge pressure waveform obtained during cardiac catheterization, the pressure range between the v wave and x trough was determined, and this value was divided by the LA reservoir strain obtained by echocardiography to calculate LA stiffness, as previously reported. LA stiffness was significantly higher in postoperative CHD patients than in controls (0.28 ± 0.17 vs. 0.13 ± 0.03, p = 0.001). Nineteen of 52 (37%) patients in their teens, 8 of 11 (73%) patients in their 20 s, and 1 of 4 (25%) patients aged > 30 years had elevated LA stiffness values. In particular, all patients with an LA reservoir strain < 20% had elevated LA stiffness. In postoperative CHD patients, LA stiffness was frequently elevated from a young age. CHD patients with elevated LA stiffness should be cautious of possible LA dysfunction in the future.

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.

Rapid Risk Stratification of Acute Ischemic Stroke Patients in the Emergency Department: The Incremental Prognostic Role of Left Atrial Reservoir Strain

OBJECTIVES

To determine the prognostic value of positive global left atrial strain (LA-GSA+), measured by two-dimensional speckle tracking echocardiography (2D-STE) in a population of acute ischemic stroke (AIS) patients without atrial fibrillation (AF), in the setting of Emergency Department (ED).

METHODS

All consecutive AIS patients with sinus rhythm on ECG and without AF history entered this prospective study. All patients underwent complete blood tests and transthoracic echocardiography implemented with 2D-STE analysis of LA strain parameters within 6-12 h after symptoms onset. At 6-months follow-up, we evaluated the composite endpoint of all-cause mortality plus cardiovascular re-hospitalizations.

RESULTS

A total of 102 AIS patients (76.4 ± 10.8 yrs, 47% males) were prospectively included. LA-GSA+ was markedly reduced in AIS patients (20.8 ± 7.7%), without any statistically significant difference between the stroke subtypes. At 6-months follow-up, 7 deaths and 27 re-hospitalizations occurred. On multivariate Cox regression analysis, variables independently associated with outcome were: LA-GSA+ (per unit) (HR 0.29, 95% CI 0.19-0.39) and C-reactive protein (CRP) (per 0.1 mg/dl) (HR 1.45, 95% CI 1.15-1.75) as continuous variables; statin therapy (HR 0.45, 95%CI 0.28-0.62), and type 2 diabetes (HR 1.65, 95% CI 1.15-2.35) as categorical variables. A LA-GSA+ ≤20.0% predicted the occurrence of the above-mentioned outcome at 6-months follow-up with 94% sensitivity and 81% specificity (AUC=0.84). Interestingly, GSA+ showed a strong inverse correlation with CRP levels (r = -0.86).

CONCLUSIONS

A LA-GSA+ ≤20% reflects a more advanced atrial cardiomyopathy and might provide a rapid and reliable prognostic risk stratification of AIS patients without AF history in the setting of ED.

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.