Atrial strain and occult atrial fibrillation in cryptogenic stroke patients: a systematic review and meta-analysis

BACKGROUND

Cryptogenic stroke (CS) remains a significant cause of morbidity. Failure to identify the underlying pathology increases the rate of recurrence. Atrial fibrillation (AF) seems to be responsible for a substantial proportion of CS. Thus, there is an unmet need to identify and properly treat those with silent AF.

PURPOSE

To investigate the association between left atrial strain and newly diagnosed AF in CS patients.

OBJECTIVES

We searched major electronic databases for articles assessing the relationship between either peak left atrial longitudinal (PALS) or peak contractile (PACS) strain-quantified using speckle tracking echocardiography-and the incidence of occult AF during the diagnostic work-up of CS patients.

RESULTS

Eleven studies (two thousand and eighty-one patients) were analyzed. Incidence of occult AF was 19%. Both PALS and PACS were significantly lower in patients with newly diagnosed AF (MD - 8.6%, 95%CI - 10.7 to - 6.4, I2 86.4% and MD - 5.5, 95%CI - 6.8 to - 4.2, I2 80.8%). According to the diagnostic accuracy meta-analysis, PALS < 20% present 71% (95%CI 47-87%) sensitivity and 71% (95%CI 60-81%) specificity for the diagnosis of occult AF, assuming a prevalence of 20%. The corresponding values for PACS < 11% are 83% (95%CI 57-94%) and 78% (95%CI 56-91%).

CONCLUSION

Both PALS and PACS are significantly lower in patients with CS and silent AF. It seems that the cut-off values mentioned above could help physicians in identifying patients who may benefit more from prolonged rhythm monitoring. More studies are needed to confirm these findings.

Epicardial Adipose Tissue and Atrial Fibrillation Recurrence following Catheter Ablation: A Systematic Review and Meta-Analysis

(1)Introduction: Catheter ablation has become a cornerstone for the management of patients with atrial fibrillation (AF). Nevertheless, recurrence rates remain high. Epicardial adipose tissue (EAT) has been associated with AF pathogenesis and maintenance. However, the literature has provided equivocal results regarding the relationship between EAT and post-ablation recurrence.(2) Purpose: to investigate the relationship between total and peri-left atrium (peri-LA) EAT with post-ablation AF recurrence. (3) Methods: major electronic databases were searched for articles assessing the relationship between EAT, quantified using computed tomography, and the recurrence of AF following catheter ablation procedures. (4) Results: Twelve studies (2179 patients) assessed total EAT and another twelve (2879 patients) peri-LA EAT. Almost 60% of the included patients had paroxysmal AF and recurrence was documented in 34%. Those who maintained sinus rhythm had a significantly lower volume of peri-LA EAT (SMD: -0.37, 95%; CI: -0.58-0.16, I2: 68%). On the contrary, no significant difference was documented for total EAT (SMD: -0.32, 95%; CI: -0.65-0.01; I2: 92%). No differences were revealed between radiofrequency and cryoenergy pulmonary venous isolation. No publication bias was identified. (5) Conclusions: Only peri-LA EAT seems to be predictive of post-ablation AF recurrence. These findings may reflect different pathophysiological roles of EAT depending on its location. Whether peri-LA EAT can be used as a predictor and target to prevent recurrence is a matter of further research.

Is there an antiarrhythmic benefit from switching to sacubitril/valsartan therapy? A systematic review and meta-analysis

Background

Sacubitril/valsartan through reverse structural remodeling and neurohormonal inhibition could play an antiarrhythmic role.

Purpose

This systematic review and meta-analysis was performed to explore the arrhythmiologic effects of switching patients with heart failure with reduced ejection fraction (HFrEF) from angiotensin converting enzyme inhibitors (ACEi) or angiotensin receptor blockers (ARBs) to sacubitril/valsartan.

Methods

We searched major databases for studies comparing device-detected, incident atrial and ventricular arrhythmias in patients with HFrEF while on ACEi/ARBs versus while on sacubitril/valsartan. For pooling the primary outcome of interest, we calculated the risk difference (RD) with the corresponding 95% confidence interval (CI) in the probability of experiencing each arrhythmic event while on ACEi/ARBs and while on sacubitril/valsartan. A random effects (DerSimonian-Laird) model was adopted.

Results

We analyzed 4 eligible studies, resulting in 497 patients with a pooled mean age of 67.8±10.36. 64% had ischemic cardiomyopathy while 98% had either an implantable cardioverter defribrillator or a cardiac resynchronization therapy device. Main comorbidities were hypertension (68.7%) and dyslipidemia (59.6%). Almost all (96.3%) patients were treated with b-blockers and 23.7% were also receiving anti-arrhythmic drugs, mainly amiodarone. After switching to sacubitril/valsartan there was a trend towards reduced risk for sustained ventricular tachycardia/fibrillation and non-sustained ventricular tachycardias (RD: −0.04, 95% CI: −0.09–0.02, I2: 65.7% and −0.06, 95% CI: −0.19–0.07, I2: 85%; respectively). Meta-regression analysis showed that patients with ischemic cardiomyopathy experience greater benefit. Incident paroxysmal atrial fibrillation/tachycardia was significantly reduced (RD: −0.09 95% CI: −0.14 to −0.03, I2: 0%), while favorable effects were noticed for the risk of appropriate shock delivery and inadequate biventricular pacing (RD: −0.06, 95% CI: −0.09 to −0.03, I2: 0% and −0.06, 95% CI: −0.11 to 0.00, I2: 35.55%, respectively). All results seem to suffer from publication bias.

Conclusion

Limited data support that switching to sacubitril/valsartan seems to be associated with reduced risk for both ventricular and atrial arrhythmias. More studies are needed to clarify the potential anti-arrhythmic role of this drug. Whether patients with frequent arrhythmias or at high arrhythmic risk may benefit from early switch is a matter of further investigation.

Funding Acknowledgement

Type of funding sources: None. Figure 1Figure 2

The role of left atrial peak systolic strain in atrial fibrillation recurrence after catheter ablation. A systematic review and meta-analysis

BACKGROUND

This systematic review and meta-analysis was performed to assess the prognostic role of left atrial peak systolic longitudinal strain (LA-PLSsys) as a predictor of atrial fibrillation (AF) recurrence after catheter ablation.

METHODS

We systematically searched major electronic databases and grey literature for studies assessing the role of pre-ablation LA-PLSsys, measured in at least two segments, in post-ablation AF recurrence, after a follow-up period of at least 6 months.

RESULTS

Seventeen eligible studies were included, resulting in 1704 patients (68.6% men) with a pooled mean age of 59.9 ± 10.6 years, 65.9% with paroxysmal AF. Recurrence occurred in 32.7% of patients. Those without recurrence had significantly higher LA-PLSsys (pooled mean ± SD: 22.22 ± 10.64%, weighted mean difference: 5.43%, 95%CI: 4.03-6.84%, I²: 82.7%). Subgroup analysis revealed that the methodology used (echocardiographic view and segments assessed), was a significant source of heterogeneity (p = 0.02). Meta-regression analysis demonstrated that the effect size was inversely related to the baseline LA volume index (p = 0.004), while concerns are also raised about patients with extremely high/low pre-ablation LA strain.

CONCLUSIONS

Pre-ablation LA-PLSsys seems to be a useful predictor of post-ablation AF recurrence, that could optimise patients selection. Nevertheless, the substantial heterogeneity that was noted may limit its clinical use. Further investigation using a uniform methodological assessment technique is required to derive a reference range, with adequate positive and negative predictive value for recurrence.

The prognostic role of late gadolinium enhancement on cardiac magnetic resonance in patients with nonischemic cardiomyopathy and reduced ejection fraction, implanted with cardioverter defibrillators for primary prevention. A systematic review and meta-analysis

BACKGROUND

Previous studies suggest that late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR) is associated with arrhythmic events in patients with nonischemic cardiomyopathy (NICM), while others have questioned the role of left ventricular ejection fraction (LVEF) as a sole predictor of future events.

OBJECTIVES

To evaluate the role of LGE on CMR in identifying patients with NICM and reduced LVEF for whom a benefit from defibrillator implantation for primary prevention is not anticipated, thus they are mainly exposed to potential risks.

METHODS

Major electronic databases were searched for studies reporting the incidence of appropriate device therapy (ADT), sudden cardiac death (SCD), and cardiac death based on the presence of LGE on CMR, among patients with NICM and reduced LVEF, implanted with a cardioverter defibrillator for primary prevention.

RESULTS

Eleven studies (1652 patients, 947 with LGE) were included in the final analysis. LGE presence was strongly associated with ADT (logOR: 1.95, 95%CI: 1.21-2.69) and cardiac death (logOR: 0.91, 95%CI: 0.14-1.68), but not with SCD (logOR: 0.26, 95%CI: -1.09-1.6). Diagnostic accuracy analysis demonstrated that contrast enhancement is a sensitive marker of future ADT and cardiac death (93%, 95%CI: 85.8-96.7%; 82.9%, 95%CI: 70.6-90.7%; respectively), with moderate specificity ( 44%, 95%CI: 27.2-62.6%; 37.7%, 95%CI: 23.4-54.6%; respectively).

CONCLUSION

LGE is a highly sensitive predictor of ADT and cardiac death in NICM patients implanted with a defibrillator for primary prevention. However, due to moderate specificity, derivation of a cutoff with adequate predictive values and probably a multifactorial approach are needed to improve discrimination of patients who will not benefit from ICDs.