Arrhythmia detection using insertable cardiac monitors after a negative electrophysiology study in Brugada syndrome: observations from a multicenter Spanish registry

Background/Introduction

Risk stratification in Brugada syndrome (BrS) remains controversial. In this respect, the role of electrophysiology study (EPS) has been subject of debate. It is common practice in some centers to implant an insertable cardiac monitor (ICM) after a negative EPS, especially in the presence of unexplained symptoms. However, the diagnostic value of this approach has never been specifically addressed.

Purpose

We aimed to describe the baseline characteristics and the main findings of a diagnostic work-up strategy using an insertable cardiac monitor (ICM) after a negative EPS in patients with BrS.

Methods

We retrospectively evaluated data from a multicenter registry including 56 BrS patients from 7 referral hospitals who received an ICM to help risk stratification. Only patients with a negative EPS (ie, non-inducible VT/VF) prior to ICM implantation were considered for this analysis. EPS protocols differed across hospitals (see Figure 1)

Results

A total of 26 patients from 5 different hospitals were studied. Mean age was 33.0±12.8 and 77% were male. Spontaneous type 1 pattern was present in 12 patients (46%). Positive genotype was found in 10 (38%) and family history of sudden cardiac death was present in 11 (42%). Previous symptoms were syncope/presyncope in 15 patients (58%) and palpitations in 3 patients (12%). The rest of the patients (30%) were asymptomatic. After a median follow-up of 33.4 months (IQR 16.5 and 43.1 months), none of the patients presented ventricular arrhythmias. ICM allowed the detection of other arrhythmias in 5 patients (19%), which led to specific therapeutic actions in all but 2 of them (see Table 1). ICM-detected arrhythmias correlated with previously reported symptoms only in one of the patients.

Conclusion

The results of this exploratory analysis support the notion that EPS in BrS has a high negative predictive value for risk stratification. ICM implantation after a negative EPS may allow the detection of incidental arrhythmias during follow-up. Despite the apparent low correlation of these findings with previously reported symptoms, this strategy may lead to important treatment decisions in a significant proportion of patients.

Funding Acknowledgement

Type of funding sources: None.

Differential effect of anticoagulation therapy in patients older versus younger than 80 years with atrial fibrillation and severe chronic kidney disease

Introduction

In non-valvular atrial fibrillation (NVAF) patients, advanced age and chronic kidney disease (CKD) raise the thrombotic and bleeding rates, making the decision of antithrombotic therapy a challenge. Therefore, we conducted an analysis to explore the efficacy and safety of anticoagulation therapy in this population (AF patients ≥80 years) in comparison with younger AF patients (<80 years).

Methods

For these results we have analyzed data from FIBRA, a multicentric Spanish retrospective registry on patients with CKD-EPI <30 ml/min/1.73 m2 and newly diagnosed NVAF. For death, multivariable Cox regression analysis was developed. For embolic and bleeding events, competing-risks regression based on Fine and Gray's proportional subhazards model was performed, being death the competing event

Results

We analyzed 405 patients with CKD-EPI <30 ml/min/1.73 m2. 232 were ≥80 years-old (57.3%). Median of CHA2DS2-VASC and HASBLED scores were 5 and 3 in patients ≥80 years, respectively, and 3 and 2 in patients <80 years, respectively. The prescription of antithrombotic therapies in elderly versus younger patients is shown in Figure 1. During a follow-up of 4.6±2.5 years, 205 died (50.6%), 34 had embolic events (8.4%) and 85 had bleeding outcomes (21.0%). After multivariate analysis, no benefit of anticoagulation therapy was found for mortality in both, older and younger patients. In patients ≥80, anticoagulation was associated with higher rates of bleeding events without a decrease in embolic outcomes.

Conclusion

In our registry, anticoagulation has not shown benefit in NVAF patients ≥80 years with glomerular filtrate rate <30 ml/min/1.73 m2, increasing the risk of bleeding events without reducing embolic outcomes.

Figure 1

Funding Acknowledgement

Type of funding source: Private grant(s) and/or Sponsorship. Main funding source(s): BMS-Pfizer alliance unconditional grant

Impact of antithrombotic therapy in the prognosis of atrial fibrillation patients with advanced chronic kidney disease

Introduction

Chronic kidney disease (CKD) is associated with an elevated thromboembolic and bleeding risk in atrial fibrillation (AF) patients, so the decision of antithrombotic therapy is a challenge.

Purpose

To analyze mortality, embolic and bleeding events in patients with advanced CKD and AF.

Methods

Multicentric retrospective registry on patients with AF and advanced CKD (CKD-EPI <30 mL/min/1.73 m2). For death, multivariable Cox regression analysis was developed. For embolic and bleeding events, competing-risks regression based on Fine and Gray's proportional subhazards model was performed, being death the competing event

Results

We analysed 405 patients with advanced CKD and newly diagnosed AF. 57 patients were not treated with antithrombotic therapy (14.1%), 80 only with antiplatelet/s (19.8%), 211 only with anticoagulation (52.1%), and 57 with anticoagulant plus antiplatelet/s (14.1%). During a follow-up of 4.6±2.5 years, 205 died (50.6%), 34 had embolic events (8.4%) and 85 had bleeding outcomes (21.0%). Bleeding event rate was significantly lower in patients without antithrombotic therapy (Figure). After multivariate analysis, anticoagulant treatment was associated with higher bleeding rates, without differences in mortality or embolic events (Table).

Conclusion

Anticoagulation therapy was associated with a significant increase in bleeding events in patients with advanced CKD and newly diagnosed AF. None of the antithrombotic therapy regimens resulted in lower embolic events rate neither benefit in mortality.

Funding Acknowledgement

Type of funding source: Private grant(s) and/or Sponsorship. Main funding source(s): This study was supported by an unconditional grant from BMS-Pfizer

P6456Role of cardiac imaging in the prediction of ventricular arrythmias, heart failure and death in dilated non-ischemic cardiomyopathy with severe left ventricular systolic disfunction

Background and purpose

Dilated non-ischemic cardiomyopathy (DCM) is associated with an increased risk of cardiac events. Implantable Cardioverter Defibrillator (ICD) is recommended in DCM with severe left ventricular ejection fraction impairment, but the evidence of its usefulness is somewhat controversial. We evaluated the predictive value of myocardial fibrosis measured by cardiac magnetic resonance (CMR) and of global longitudinal strain (GLS) in the incidence of adverse cardiac events.

Methods

From 2009 to 2019, sixty-six patients with DCM were evaluated. CMR with a 1.5 Tesla scanner was performed, and the presence and extent of late gadolinium enhancement (LGE) was blindly assessed. GLS was measured using speckle-tracking 2D echocardiography. We examined the incidence of sustained ventricular arrhythmias (SVA, including appropriate anti-tachycardia pacing and shocks), admissions due to heart failure (HF) and all-cause mortality.

Results

62.1% of the patients were male, with a median age of 63.8 years. 50.0% had cardiac resynchronization therapy and 73.9% had ICD as primary prevention therapy. Median LVEF was 25.7%.

Median follow-up was 32 months. In that period, 10.6% of patients died, 25.8% had hospital admissions due to HF, and 9.2% had SVA. A burden of LGE over 14% was independently associated with higher risk of SVA (3.0% vs 19.2%, p=0.041). This cut-off value had a sensitivity of 83.3% and a negative predictive value of 97.0%. LGE was not associated with higher risk of HF admissions (27.3% vs 23.1%, p=0.731) or death (9.1% vs 11.5%, p=0.757).

On the other hand, GLS was not associated with higher risk of SVA (8.7% vs 4.55% for a cut-off value of −10.6%, p=0.577), HF admissions (26.1% vs 30.4%, p=0.743) or death (8.7% vs 8.7%, p=1.00).

Table 1. Main etiologies of DCM Causes N (%) Idiopathic 43 (65.2) Alcoholic 6 (9.1) Chemotherapy 4 (6.1) Non-compaction 4 (6.1) Familiar 3 (4.6) Thoracic radiotherapy 2 (3.0) Chagas disease 2 (3.0)

Conclusions

The burden of myocardial fibrosis measured by LGE is a high sensitive marker for the development of SVA. However, is not a predictive tool for HF admissions or all-cause mortality. GLS was not associated with the incidence of cardiac events in this population.