Atrial fibrillation risk scores to evaluate left atrial substrate based on voltage analysis in long-standing persistent type of arrhythmia.

BACKGROUND: Pre-ablation identification of left atrial (LA) low voltage areas (LVA) among long-standing persistent atrial fibrillation (LSPAF) population remains challenging. AIMS: The aim of the study was to analyze the potential of selected scores originally developed to assess arrhythmia recurrences, thromboembolic complications, or progression from paroxysmal to persistent AF to predict the presence of LA-LVA in LSPAF patients. METHODS: One hundred and fifty-two patients underwent pulmonary vein isolation followed by high-density-high-resolution LA voltage mapping. AF risk scores, such as APPLE, ATLAS, CAAP-AF, DR-FLASH, CHA2DS2-VASc, and HATCH were retrospectively calculated. A receiver operating characteristic curve analysis was performed to evaluate the ability of the scores to predict LVA. RESULTS: Low voltage areas were detected in 52% of the patients. 28% of the patients with LVA presented severe global LVA burden, whereas 56% of the patients showed a disseminated pattern of remodeling. CAAP-AF ≥7, DR-FLASH ≥4, and CHA2DS2-VASc ≥3 predicted the presence of LVA, whereas ATLAS ≤7 indicated the absence of LVA. ATLAS ≤8, CAAP-AF ≤9, DR-FLASH ≤4, and CHA2DS2-VASc ≤3 predicted the absence of severe LVA. APPLE ≤3 and CHA2DS2-VASc ≤2 predicted the absence of a LVA disseminated pattern. Among predictive scores, ATLAS (AUC, 0.633, 95% CI, 0.543-0.723, P = 0.004), DR-FLASH (AUC, 0.696; 95% CI, 0.594-0.81; P <0.001), and CHA2DS2-VASc (AUC, 0.644; 95% CI 0.518-0.77; P = 0.025) were the best predictors for the absence of LVA, severe LVA and a disseminated pattern of LVA, respectively. CONCLUSIONS: Atrial fibrillation risk stratification with specific scoring systems can unmask the presence of LA-LVA in the LSPAF population.

Left and right atrial appendage functional features as predictors for voltage-defined left atrial remodelling in patients with long-standing persistent atrial fibrillation.

It was hypothesised that left atrial (LA) fibrosis identified by the presence of low-voltage areas (LVA) may influence the mechanical and electrical function of the left (LAA) and right (RAA) atrial appendage among the long-standing persistent atrial fibrillation (LSPAF) population. 140 consecutive patients underwent voltage mapping of LA with a multielectrode catheter following pulmonary vein isolation and restoration of sinus rhythm with cardioversion. Echocardiography determined LAA peak outflow and inflow velocities and intracardiac catheter-based mean LAA and RAA AF cycle length (AFCL) were obtained during AF before ablation. The impact of flow velocities and AFCL on the prevalence and location of LVA was further evaluated. LVA were detected in 54% of the patients. 14% of the patients presented severe global LVA burden > 20% of the total LA surface area. 29% of the patients presented a disseminated pattern of remodelling as 3 out of 5 LA segments were affected. LAA AFCL, RAA AFCL, LAA flow velocities did not predict the absolute presence of LVA. However LAA AFCL > 155 ms predicted disseminated LVA pattern and LAA AFCL > 165 ms severe LVA incidence. LAA AFCL > 155 ms was predictive for existence of LVA within antero-septal LA segments whilst LAA emptying velocity ≤ 0.2 m/s within lateral wall. Moreover RAA AFCL > 165 ms was strongly related to the presence of LAA AFCL > 15 ms and > 165 ms. LAA and RAA functional assessment was predictive of the presence of advanced stages of voltage-defined LA fibrosis and its regional distribution among LSPAF population.