Cardiac implantable electronic device infections: prognostic value of the PADIT score and its cost-utility implications for antimicrobial envelope use in the United Kingdom

Background

The incidence of cardiac implantable electronic device (CIED) infections is rising.

Purpose

We examined the factors associated with CIED infection, assessed the prognostic power of the PADIT risk score, and modelled the cost-utility of selective TYRX antimicrobial envelope use for preventing CIED infections.

Methods

Data were extracted from 2016 to 2019, and included all de novo implants, generator changes and lead interventions for transvenous CIEDs at a high-volume UK centre. CIED infection was defined as hospitalisation for device infection within 12 months of a procedure. Cost-utility analysis was informed by standardised tariffs, and quality adjusted life year (QALY) and efficacy data was extrapolated from analysis of the WRAP-IT trial.

Results

6,035 patients underwent 7,383 procedures; CIED infection occurred in 59 individuals (0.8%). In addition to the constituents of the PADIT score, lead extraction (HR 3.3 (1.9–6.1), p<0.0001), C-reactive protein >50mg/l (HR 3.0 (1.4–6.4), p=0.005), re-intervention within two years (HR 10.1 (5.6–17.9), p<0.0001), and procedure duration over two hours (HR 2.6 (1.6–4.1), p=0.001) were independent predictors of infection. Increased PADIT score was strongly associated with infection (AUC: 0.82, HR per point increase: 1.36 (1.27–1.47), p<0.0001). A cost-utility model assigning TYRX envelopes to patients with PADIT scores ≥6 predicted a reduction in infections (number needed to treat: 72) and a cost per QALY gained within the UK's (NICE) cost-effectiveness threshold (£25,107).

Conclusions

The PADIT score was a powerful predictor of CIED infections in a heterogeneous population,and may facilitate cost-effective TYRX envelope allocation in selected high-risk patients.

Funding Acknowledgement

Type of funding sources: None.

Transseptal puncture for left atrial ablation: risk factors for cardiac tamponade and a proposed causative classification system

Aims

Cardiac tamponade is a high morbidity complication of transseptal puncture (TSP). We examined the associations of TSP‐related cardiac tamponade (TRCT) for all patients undergoing left atrial ablation at our center from 2016 to 2020.

Methods and Results

Patient and procedural variables were extracted retrospectively. Cases of cardiac tamponade were scrutinized to adjudicate TSP culpability. Adjusted multivariate analysis examined predictors of TRCT. A total of 3239 consecutive TSPs were performed; cardiac tamponade occurred in 51 patients (incidence: 1.6%) and was adjudicated as TSP‐related in 35 (incidence: 1.1%; 68.6% of all tamponades). Patients of above‐median age [odds ratio (OR): 2.4 (1.19–4.2), p = .006] and those undergoing re‐do procedures [OR: 1.95 (1.29–3.43, p = .042] were at higher risk of TRCT. Of the operator‐dependent variables, choice of transseptal needle (Endrys vs. Brockenbrough, p > .1) or puncture sheath (Swartz vs. Mullins vs. Agilis vs. Vizigo vs. Cryosheath, all p > .1) did not predict TRCT. Adjusting for operator, equipment and demographics, failure to cross the septum first pass increased TRCT risk [OR: 4.42 (2.45–8.2), p = .001], whilst top quartile operator experience [OR: 0.4 (0.17–0.85), p = .002], transoesophageal echocardiogram [TOE prevalence: 26%, OR: 0.51 (0.11–0.94), p = .023], and use of the SafeSept transseptal guidewire [OR: 0.22 (0.08–0.62), p = .001] reduced TRCT risk. An increase in transseptal guidewire use over time (2016: 15.6%, 2020: 60.2%) correlated with an annual reduction in TRCT (R² = 0.72, p < .001) and was associated with a relative risk reduction of 70%.

Conclusions

During left atrial ablation, the risk of TRCT was reduced by operator experience, TOE‐guidance, and use of a transseptal guidewire, and was increased by patient age, re‐do procedures, and failure to cross the septum first pass.

ProGlide venous closure device facilitates early ambulation following cryoablation of atrial fibrillation

Funding Acknowledgements

Type of funding sources: Foundation. Main funding source(s): Heart Foundation

Background

Same-day discharge following atrial fibrillation (AF) ablation is increasingly common. ProGlide device suture-mediated vascular closure (PD) offers a technique that may expedite mobilisation following large-bore (&gt;12F) venous access. The utility of PD closure following cryoablation of AF has not been reported.

Purpose

We sought to evaluate haemostasis and early ambulation outcomes in patients receiving the ProGlide compared with conventional techniques.

Methods

104 consecutive patients undergoing cryoballoon pulmonary vein isolation (PVI) for paroxysmal or persistent at a single high-volume institution were included. PVI was  performed via a standardised approach including sedation, ultrasound-guided vascular access for 14F Cryosheath and second 7F sheath, anticoagulation protocol, transeptal puncture, 28mm cryoballoon and nurse-led same-day discharge protocol. Haemostasis was achieved using the Perclose Proglide device (PD) in the 14F access point ("pre-closure" technique) plus 5 minutes manual pressure at the 7F sheath site. Alternatively, a figure-of-eight/Z-suture (ZS) was employed for closure according to operator preference. Protamine was used for heparin reversal in all patients. Safety outcomes of major bleeding, haematoma and minor bleeding were assessed. Time to ambulation (TTA), time to discharge (TTD), same-day discharge and complications at initial follow-up were measured.

Results

Overall, mean age was 64 ± 11 years, 65 (64%) were male and 52 (50%) of patients had paroxysmal AF, there were no significant differences between group demographics, with 31 patients (30%) in the PD group and 73 (70%) in the ZS group. All patients had uninterrupted oral anticoagulation throughout the periprocedural period. No major femoral bleeding complications requiring intervention occurred in either group. Haematomas occurred in none of the PD group compared with 2 (2.8%) in the ZS group. Incidence of minor bleeding was not significantly different between groups (PD: 3 [9.7%] vs ZS: 2 [2.7%], p = 0.155). Mean TTA was significantly shorter in the PD group (3.3 ± 1.1 vs 4.1 ± 1.7 hrs, p = 0.025). However, there was no significant difference in same-day discharge (PD: 25 [81%] vs ZS: 53 [73%], p = 0.386) and TTD (5.0 ± 3.6 vs 6.1 ± 4.2 hrs, p = 0.275) between groups. 1 patient complained of groin pain which delayed discharge in the ZS group not seen in the PD group. After a mean follow-up of 2.2 ± 1.4 months, there were no differences in major or minor complications.

Conclusion

Use of the Proglide closure device was associated with significant reductions in time to ambulation compared with Z-suture haemostasis following cryoablation of AF, and groin access complications were uncommon across groups.  PD closure may contribute to further streamlining patient pathways in day-case AF ablation.

Non Type-1 Brugada pattern, diagnostic yield of 5 ECG criteria in a young adult cohort

Introduction

Distinguishing between non-Type 1 Brugada pattern (non-T1BrP) and an athlete's ECG remains challenging and may have important prognostic implications. We aimed to study prevalence and the diagnostic yield of experts and non-experts for the electrocardiographic non-T1BrP criteria in the young adults from the Sudden Cardiac Death-Screening Of risk factorS (SCD-SOS) cohort.

Methods

We performed a cross-sectional study in which we reviewed 14662 ECGs of SCD-SOS survey participants and selected 2494 that presented a rSr'-pattern in V1-V2. Among these, 98 were classified by experts in hereditary arrhythmic syndromes for the presence of non-T1BrP and by non-experts who performed manual measurements of the diagnostic criteria based on triangle formed by r'-wave. We estimated intra and interobserver concordance for each criterion, and used logistic regression and receiver operating characteristics (ROC) analysis and C-statistics for diagnostic accuracy and definition of the most appropriate cut-off values.

Results

We detected a rSr'-pattern in V1-V2 in 17% of the individuals and found that it was associated with higher PQ and QTc intervals, male gender and lower BMI. The manual measurements of non-T1BrP criteria were reproducible: we had high intraobserver concordance coefficients (CC) ranging from 0.90 to 0.94 (except for d(B) that had 0.66), but interobserver CC were lower (0.45–0.68). The measurements performed were highly correlated with non-T1BrP diagnosis and the criteria with higher discriminatory capacity were the distance d(B) (AUC 0.77; 95% CI0.69–0.84) and the degree of ST-ascent (AUC 0.79; 95% CI 0.72–0.86). The cut-offs defined by other authors had very low sensitivity (8–12%), despite high specificity (98%), so we defined new cut-offs: d(A) ≥2mm, d(B) ≥1.25mm, d(B)/h ≥0.38, β-angle ≥19° and ST-ascent ≥1mm. The addition of the degree of ST-ascent to a model with these 4 parameters presented an increase in C-statistics from 0.77 (95% CI: 0.68–0.86) to 0.83 (95% CI: 0.75–0.91) for the diagnosis of non-T1BrP by an expert in Sudden Arrhythmic Death and Channelopathies.

Conclusion

A rSr'-pattern in precordial leads V1-V2 is a frequent finding and the detection of non-T1BrP by using the aforementioned 5 measurements is reproducible and accurate. In this study, we describe new cut-off values that may help untrained clinicians to identify young individuals who should be referred for provocative drug testing for Brugada Syndrome.

Accuracy of non-T1 BrP criteria

Funding Acknowledgement

Type of funding source: None

P529Efficacy and safety of S-ICD implantation without use of defibrillation threshold testing: a retrospective multicentric observational study

Introduction

The subcutaneous ICD (S-ICD) is a valid alternative to transvenous systems (TV-ICD) for the treatment of life-threatening arrhythmias, and the extravascular position of the lead allows a significant reduction of the risk of infection. Current guidelines recommend defibrillation threshold testing (DFT) at the time of S-ICD implantation (class I). Although randomised trials have proven the safety of TV-ICD implantation with no DFT, it is unclear whether such an approach could be adopted for S-ICD as well. The PRAETORIAN score, based on post-implantation chest X-ray, can accurately predict a high defibrillation threshold after S-ICD implantation. The aim of this retrospective multicentre study was to evaluate the efficacy and safety of S-ICD implantation with no DFT.

Methods

We enrolled 203 consecutive patients undergoing S-ICD implantation in six different centres between October 2012 and January 2019. It was left at discretion of the operator whether performing or not DFT at the time of the procedure. Baseline device settings were collected, and the PRAETORIAN score was retrospectively calculated whenever chest X-ray was available. Both remote or in-clinic device interrogation reports were systemically analysed, and all the shocks and arrhythmia episodes identified. All the patients provided consent form and ethical approval was obtained.

Results

The population (mean age 57.6 ± 14.2) was divided in two groups, based on whether DFT was performed at the time of the S-ICD implantation: 72 patients (35.4%) underwent DFT (DFT+ group), while 131 patients (64.5%) did not (DFT- group). In the DFT- group, mean LVEF was lower (32 ± 8% vs 42 ± 17%, p &lt; 0.0001) and prevalence of diabetes mellitus and atrial fibrillation higher compared to the DFT+ group (27.5% vs 13.9%, p = 0.04 and 38.9% vs 19.44%, p = 0.007; respectively). In addition, the indication for S-ICD was more frequently primary prevention in the DFT- vs DFT+ group (70.8% vs 90.8%, p = 0.0004; respectively). No differences in terms of device programming were identified between the two cohorts. The PRAETORIAN score was significantly higher in the DFT- vs DFT+ patients (50 ± 26 vs 36 ± 18, p = 0.032; respectively). After a median follow-up of … months, we observed 5 appropriate shocks in 3 patients from the DFT+ group vs. 15 shocks in 8 patients from the DFT- group (p = 0.81). All the life-threatening arrhythmias were successfully recognised and treated by the device. DFT was complicated by pulseless electrical activity in one patient. One patient in the DFT- group suffered from an episode of ventricular tachycardia requiring a total of 4 shocks for being terminated. Six patients in the DFT- group died for non-arrhythmic causes. On the Kaplan-Meier analysis, cumulative survival was comparable between the two groups (log rank p value = 0.13).

Conclusions

This study suggests that implantation of S-ICD with no DFT might be reasonable. These results should be confirmed in prospective randomised trials.

P309R' wave in precordial leads V1-V2 in patients from the young SCD-SOS cohort

Introduction

Sudden Cardiac Death – Screening Of risk factorS (SCD-SOS) survey aimed to screen for warning signs of potential channelopathies and cardiomyopathies that may course with sudden cardiac death in the young (≤40 years old) and consisted in an ECG and a digital-based previously validated questionnaire.

Purpose

We aimed to study clinical and electrocardiographic characteristics of young patients from the SCD-SOS cohort who presented with an r'-wave in precordial leads V1 and V2.

Methods

All the ECG were screened for the detection of an r'-wave in precordial leads V1 and V2. The ECGs selected were reviewed by a second investigator (agreed in 97.7% of the cases). We performed classical descriptive statistics and multivariate logistic regression to compare patients with and without r'-wave in these leads.

Results

From a total of 14669 patients who had an ECG performed as part of the SCD-SOS survey, 17% displayed an r'-wave in precordial leads V1 and V2 and 0.4% had complete right bundle branch block (RBBB). Patients with rSr' pattern had a mean age of 20±5 years old, 54% of them were male, they had a mean body mass index (BMI) of 22±3kg/m2, and 54% practiced sports regularly, with a mean of 5±4 hours of physical activity per week. Regarding previous symptoms reported by these individuals, 24% (n=487) reported a transient loss of consciousness, 15% (n=310) a reflex syncope, 3% (n=58) had unexplained syncope and 21% (n=425) palpitations. Sudden death in relatives before 50 years-old was present in 11% (n=172) of the patients with an r'-wave in V1-V2. After adjusting for heart rate and physical activity, PQ interval (OR 1.007 - CI95% 1.004–1.010, p<0.001), QTc interval (OR 1.009 - CI95% 1.005–1.012, p<0.001), male gender (OR 2.438 - CI95% 2.144–2.772, p<0.001) and BMI (OR 0.881 - CI95% 0.864–0.900, p<0.001) were independently associated with the presence of r'wave in precordial leads V1-V2. Unexplained syncope, palpitations and family history of sudden death were not associated with r'-wave in the young SCD-SOS population.

Conclusions

We conclude that r'-wave in V1-V2 is a frequent finding in the young population and that it is associated with higher PQ and QTc intervals. The prognostic implications of this pattern are unknown, but thorough differential diagnosis is warranted since this pattern may correspond to incomplete RBBB/athlete's ECG, and may also be suggestive of other potentially serious conditions such as Type 2 Brugada pattern and multiple causes of right ventricular enlargement. Finally, this pattern is also associated with male gender and lower BMI, suggesting a dependence on anatomical factors.