A Systematic Review on the Correlations between Left Atrial Strain and Cardiovascular Outcomes in Chronic Kidney Disease Patients

Assessment of left atrial function provides incremental value: the left atrial volumetric/mechanical coupling index in patients with chronic kidney disease

Background

Heart failure is a common cause of adverse cardiovascular outcomes in patients with chronic kidney disease (CKD). Left atrial (LA) characteristics are thought to be involved in the development of heart failure. However, LA assessment is complex. Though a variety of parameters have been defined, there is no single parameter that best defines LA function. Pilot data indicate that left atrial volumetric/mechanical coupling index (LACI) may be useful, but data with CKD are lacking.

Aim

The objective of this study was to define LACI in a cohort of patients with CKD and to assess its value in evaluating LA function and predicting heart failure.

Methods

A cohort of patients with CKD was enrolled at our hospital between 2021 and 2023. Follow-up was performed for heart failure. LACI is a volumetric to mechanical coupling index, calculated as the ratio of the LA volume index to the tissue-Doppler myocardial velocity at atrial contraction. Spearman's rank correlation or Pearson's correlation was used to calculate the correlation between LACI and echocardiographic/hemodynamic variables. Receiver operating characteristic curve (ROC) analysis was utilised to derive the area under the curve (AUC) for LACI, LVGLS, LASr, LASct and LASI for the detection of heart failure. Kaplan-Meier survival curves were employed to compare clinical outcomes based on LACI thresholds. A multivariable logistic regression analysis was employed to assess the relationship between risk factors and elevated LACI. Cox proportional hazards regression was used to identify risk factors for heart failure.

Results

LACI showed a positive correlation with NT-proBNP, CK-MB, LAVI, E/e' and LASI (r = 0.504, 0.536, 0.856, 0.541 and 0.509, p < 0.001); and a negative correlation with LASr (r = -0.509, p < 0.001). On the ROC analysis for the determination of heart failure, the AUC of LACI was comparable to those of LVGLS (0.588 vs. 509, p = 0.464), LASr (0.588 vs. 0.448, p = 0.132), LASct (0.588 vs. 0.566, p = 0.971) and LASI (0.588 vs. 0.570, p = 0.874). The cardiovascular risk factors increased by LACI were age, BMI, diabetes, triglycerides, LA size, LASr, LASI, E/A, E/e' and EF (p < 0.05). During a median follow-up of 16 months (range, 6-28 months), the event-free survival curves demonstrated a higher risk of heart failure in the group with LACI > 5.0 (log-rank test: P < 0.001). LACI > 5.0 was an independent predictor of heart failure [OR: 0.121, 95% CI (0.020-0.740), p = 0.022].

Conclusion

LACI may prove to be a valuable tool for assessing LA function in patients with CKD, and could be integrated into the routine assessment of LA for the purpose of prognostic assessment and clinical decision-making in patients with CKD.

Left Atrial Strain Insights in Atrial Fibrillation and the Interplay with Metabolic Syndrome

INTRODUCTION

Understanding the interplay between metabolic syndrome and left atrial (LA) function is crucial, especially in patients newly diagnosed with atrial fibrillation (AF). We evaluated the association between subclinical atrial function and metabolic syndrome in patients diagnosed with new-onset AF.

METHODS

A retrospective analysis was conducted on 220 patients, aged between 20 and 100 years, who were newly diagnosed with AF. These patients were divided into two groups based on the presence or absence of metabolic syndrome. LA reservoir strain, a measure of LA function, was assessed using transthoracic echocardiography. Statistical methods, including receiver operating characteristic (ROC) curve and logistic regression analyses, were employed to evaluate the association between LA strain and metabolic syndrome.

RESULTS

Among the 220 patients, 108 had metabolic syndrome and displayed more adverse clinical characteristics. The LA reservoir strain was significantly lower in this group (9.7% ± 5.2% vs. 12.0% ± 5.8%, p = 0.003). ROC curve analysis identified 9.3% as the optimal cutoff value for predicting metabolic syndrome, with a sensitivity of 50.9% and specificity of 70.5%. Further, multivariate analysis confirmed that an LA reservoir strain below 9.3% was independently linked to metabolic syndrome (odds ratio 4.261, 95% confidence interval 1.134-16.009, p = 0.032).

CONCLUSIONS

The findings reveal a significant association between lower LA reservoir strain values and the presence of metabolic syndrome in patients newly diagnosed with AF. An LA strain value below 9.3% serves as a critical diagnostic and prognostic indicator, highlighting its clinical importance in managing patients with AF.

Predictive value of left atrial strain analysis in adverse clinical events in patients with hypertrophic cardiomyopathy: a CMR study

BACKGROUND

A subset of patients with hypertrophic cardiomyopathy (HCM) will experience adverse clinical events such as heart failure (HF), cardiovascular death, and new-onset atrial fibrillation (AF). Current risk stratification methods are imperfect and limit the identification of patients at high risk for HCM. This study aimed to evaluate the role of cardiac magnetic resonance (CMR)-derived left atrial strain parameters in the occurrence of adverse clinical events in patients with HCM.

METHODS

Left atrial (LA) structural, functional, and strain parameters were evaluated in 99 patients with HCM and compared with 89 age-, sex-, and BMI-matched control subjects. LA strain parameters were derived from CMR two- and four-chamber cine images by a semiautomatic method. LA strain parameters include global longitudinal strain (GLS) and global circumferential strain (GCS). The LA GLS includes reservoir strain (GLS reservoir), conduit strain (GLS conduit), and booster strain (GLS booster). Three LA GLS strain rate (SR) parameters were derived: SR reservoir, SR conduit, and SR booster. The primary endpoint was set as a composite of adverse clinical events, including SCD, new-onset or worsening to hospitalized HF, new-onset AF, thromboembolic events, and fatal ventricular arrhythmias.

RESULTS

LA GLS, GLS SR and GCS were impaired in HCM patients compared to control subjects (all p < 0.001). After a mean follow-up of 37.94 ± 23.69 months, 18 HCM patients reached the primary endpoint. LA GLS, GLS SR, and GCS were significantly lower in HCM patients with adverse clinical events than in those without adverse clinical events (all p < 0.05). In stepwise multiple Cox regression analysis, LV SV, LA diameter, pre-contraction LAV (LAV pre-ac), passive LA ejection fraction (EF), and LA GLS booster were all independent determinants of adverse clinical events. LA GLS booster ≤ 8.9% was the strongest determinant (HR = 8.9 [95%CI (1.951, 40.933)], p = 0.005). Finally, LA GLS booster provided predictive adverse clinical events value (AUC = 0.86 [95%CI 0.77-0.98]) that exceeded traditional outcome predictors.

CONCLUSION

LA strain assessment, a measure of LA function, provides additional predictive information for established predictors of HCM patients. LA GLS booster was independently associated with adverse clinical events in patients with HCM.