Prognostic value of cardiac deceleration capacity in patients with atrial fibrillation after catheter ablation: A systematic review and meta-analysis.

INTRODUCTION: Cather ablation (CA) is a well-recognized treatment alternative for atrial fibrillation (AF) patients despite more than 20% ablation-treated patients suffering from AF recurrence. The underlying mechanism of AF recurrence postablation is probably associated with high cardiac parasympathetic activity, which can be assessed with deceleration capacity (DC) of heart rate. Given that the relationship between DC and AF recurrence is still controversial, this systematic review and meta-analysis was performed to investigate the characteristics of DC in patients with and without AF recurrence, evaluating the prognostic value of DC in AF patients after CA. METHODS: A literature search was systematically performed in the Embase, PubMed, Web of Science, China National Knowledge Infrastructure (CNKI), and Wanfang databases until October 01, 2023. The observational studies reporting either the pre- and postablation DC in both recurrence and non-recurrence groups or the ratios based on DC for predicting AF recurrence were mainly included. Weighted mean differences (WMD) or odds ratios (OR) based on DC would be calculated with a random-effect model, if heterogeneity estimated with the I2 index and Q statistic was significant (I2 > 50% or p < .05); otherwise, a fixed-effect model would be utilized. RESULTS: A total of eight observational studies involving 914 AF patients treated with radiofrequency or cryoballoon ablation were included in this study. Ablation-treated patients with AF recurrence had the higher DC postablation in relation to those without recurrence (WMD, 1.00; 95% confidence interval [CI], 0.33-1.67; p < .01), which was present up to 3 months of follow-up (WMD, 1.54; 95% CI, 1.11-1.96; p < .01), whereas there was no statistical significance in DC before ablation between recurrence and non-recurrence groups (WMD, 0.34; 95% CI, -0.12 to 0.79; p = .15). The high DC postablation was a risk factor for AF recurrence in ablation-treated patients (OR, 2.17; 95% CI, 1.44-3.25; p < .01). CONCLUSION: The high DC postablation was associated with the risk of AF recurrence, suggesting that DC may act as a prognostic indicator in AF patients treated with CA.

Comparisons of diagnostic performance and the reliability in identifying ACL injury between two measuring protocols of anterior tibial subluxation on MR images.

OBJECTIVES: To evaluate the diagnostic performance in identifying an anterior cruciate ligament (ACL) injury and the reliability between two measuring protocols of anterior tibial subluxation (ATS). MATERIALS AND METHODS: A total of 165 patients with ACL injury and 157 ACL-intact patients were included in this study. Two different measuring protocols of ATS were performed on sagittal MR images, including the modified protocol using the longitudinal tibial axis (axis protocol) and the established protocol using a line perpendicular to the tibial plateau (plateau protocol). Receiver-operating characteristic (ROC) curves were calculated to evaluate the diagnostic performance in identifying an ACL injury, and areas under the curves (AUCs) were compared between the two protocols. Intra- and interobserver reliability tests were performed to evaluate the reliability of the measurements. RESULTS: Lateral ATS (P < 0.001) and medial ATS (P < 0.001) were increased in patients with ACL injury under both protocols. To identify an ACL injury, ATS measured under the axis protocol showed higher AUC values than the plateau protocol, including lateral ATS (AUC 0.828 vs. 0.688, P < 0.001), medial ATS (AUC 0.829 vs. 0.789, P = 0.013), and the combined indicator of lateral and medial ATS (AUC 0.885 vs. 0.810, P < 0.001). Reliability tests showed that both protocols were reliable. CONCLUSIONS: ATS measured under the modified protocol using the longitudinal tibial axis showed superior diagnostic performance in identifying an ACL injury compared to the established protocol, indicating that the modified protocol may better reflect the characteristics of an ACL-deficient knee.

Anterior tibial subluxation measured under a modified protocol is positively correlated with posterior tibial slope: a comparative study of MRI measurement methods.

PURPOSE: Anatomic factors, such as posterior tibial slope (PTS) and anterior tibial subluxation (ATS) obtained by quantitative measurement, have been proposed as predictors for clinical outcomes of anterior cruciate ligament (ACL) reconstruction. However, the correlation between PTS and ATS is controversial, and the method for quantitative ATS measurement remains unsettled. This study aimed to identify the correlation between PTS and ATS in patients with injured and intact ACLs and compare the two ATS measuring protocols. METHODS: This study included 128 ACL-injured and 176 ACL-intact patients with no concomitant ligament injuries. PTS and ATS were measured on sagittal MRI. ATS was measured using two measuring protocols, including the modified protocol using the longitudinal tibial axis (axis protocol) and the established protocol using a line perpendicular to the tibial plateau (plateau protocol). Correlation analyses between PTS and ATS and between PTS and the difference in the ATS value measured under the two protocols (ATSdiff) were performed. The difference between the two ATS measuring protocols was further analyzed by trigonometric analysis. Intra- and interobserver reliability tests were performed for the axis protocol. RESULTS: Under the axis protocol, ATS was positively correlated with PTS in both the ACL-injured and ACL-intact groups (p < 0.001). Under the plateau protocol, no correlation was observed in the ACL-injured group. In the ACL-intact group, no correlation was observed for lateral ATS, and a negative correlation was observed for medial ATS (p = 0.001). ATSdiff was positively correlated with PTS (p < 0.001), indicating that the two protocols varied greatly in those with a steep PTS. Trigonometric analysis showed that a steep PTS influenced the measurement of ATS under the plateau protocol but not the axis protocol. Intra- and interobserver reliability tests showed good-to-excellent strength of reliability for the ATS measurement under the axis protocol. CONCLUSION: ATS measured under the axis protocol was positively correlated with PTS, indicating that a steep PTS was associated with a worse anatomic tibiofemoral relationship. The axis protocol for ATS measurement is a promising method for clinical use since it is not influenced by PTS and reflects the global position of the tibia. LEVEL OF EVIDENCE: III.

Feasibility and Safety of Pulsed Field Ablation at the Ventricular Outflow Tract Using Focal Point Catheter.

BACKGROUND: Ventricular arrhythmias commonly originate from the ventricular outflow tract (VOT). It remains unexplored whether pulsed-field ablation (PFA) can create durable lesions safely at the VOT. OBJECTIVE: This study aimed at evaluating the feasibility and safety of a novel PFA catheter to deliver focal ablation to the VOT, especially pulmonary and aortic sinus cusps (PSCs and ASCs). METHODS: Twelve swine were divided into three groups: 24-hour, 2-week, and 4-week post-ablation. PFA was delivered to pre-defined sites of PSCs and ASCs with a focal point catheter, positioned via mapping system, fluoroscopy, and intracardiac echocardiography (ICE). Electrophysiologic assessment, coronary angiography, transesophageal echocardiogram (TEE), gross and histologic examination were performed to evaluate the impact of PFA delivery on cardiac structure and function. RESULTS: All subjects survived, and no adverse events were observed. There was a significant decrease in voltage amplitude and increase in pacing thresholds at PSCs and ASCs. There were no significant differences in A-H or H-V intervals between pre- and post-ablation (A-H, P = .70; H-V, P = .90). After PFA delivery to ASCs, coronary arteries were fully perfused in each heart, without ST-segment elevation observed. No severe valvular dysfunction was observed based on ICE and TEE. Gross and histologic examination confirmed the creation of well-demarcated lesions at the targeted sites without damage to adjacent structures. CONCLUSION: PFA delivered via the focal point catheter could create durable lesions at PSCs and ASCs without damage to coronary arteries, atrioventricular block, or valvular dysfunction, indicative of the feasibility and safety of this novel PFA catheter at the VOT.

Anterior and rotational tibial subluxation in the setting of anterior cruciate ligament injuries: An MRI analysis.

BACKGROUND: The relationship between preoperative tibiofemoral position and failure of anterior cruciate ligament (ACL) reconstruction has been widely discussed. Most established methods for measuring tibiofemoral position on magnetic resonance imaging (MRI) mainly focus on anterior tibial subluxation (ATS), while a quantitative measuring method for rotational tibial subluxation (RTS) is still undetermined. Moreover, there are still controversies about the related factors for ATS. The aim of this study was to quantitatively describe preoperative ATS and RTS in ACL-injured and ACL-intact knees and identify the related factors for ATS and RTS based on MRI images. METHODS: Demographic data and preoperative MRIs of 104 ACL-injured patients were retrospectively analyzed. ACL-intact knees were 1:1 matched as control group. ATS was measured using longitudinal tibial axis, and RTS was determined by the difference between lateral and medial ATS. Related factors for ATS and RTS were examined. RESULTS: Increased lateral ATS (P < 0.0001), medial ATS (P < 0.0001) and RTS (P = 0.0479) were observed in ACL-injured knees compared with the control group. Increased posterior tibial slope (PTS), Beighton Score ≥ 4, presence of meniscal injury and long injury-to-MRI time were identified as being correlated with the increase of ATS. Factors for the increase of RTS were increased lateral PTS, Beighton score ≥ 4, presence of lateral meniscal injury, and left side. CONCLUSIONS: In ACL-injured knees, tibia not only subluxated anteriorly in both lateral and medial compartments, but also rotated internally. During preoperative planning, attentions should be paid to the factors that are correlated with altered tibiofemoral position.