Conduction System Stimulation to Avoid Left Ventricle Dysfunction.

BACKGROUND: Right ventricular apical pacing (RVAP) can produce left ventricle dysfunction. Conduction system pacing (CSP) has been used successfully to reverse left ventricle dysfunction in patients with left bundle branch block. To date, data about CSP prevention of left ventricle dysfunction in patients with preserved left ventricular ejection fraction (LVEF) are scarce and limited mostly to nonrandomized studies. Our aim is to demonstrate that CSP can preserve normal ventricular function compared with RVAP in the setting of a high burden of ventricular pacing. METHODS: Consecutive patients with a high-degree atrioventricular block and preserved or mildly deteriorated LVEF (>40%) were included in this prospective, randomized, parallel, controlled study, comparing conventional RVAP versus CSP. RESULTS: Seventy-five patients were randomized, with no differences between basal characteristics in both groups. The stimulated QRS duration was significantly longer in the RVAP group compared with the CSP group (160.4±18.1 versus 124.2±20.2 ms; p<0.01). Seventy patients were included in the intention-to-treat analyses. LVEF showed a significant decrease in the RVAP group at 6 months compared with the CSP group (mean difference, -5.8% [95% CI, -9.6% to -2%]; P<0.01). Left ventricular end-diastolic diameter showed an increase in the RVAP group compared with the CSP group (mean difference, 3.2 [95% CI, 0.1-6.2] mm; P=0.04). Heart failure-related admissions were higher in the RVAP group (22.6% versus 5.1%; P=0.03). CONCLUSIONS: Conduction system stimulation prevents LVEF deterioration and heart failure-related admissions in patients with normal or mildly deteriorated LVEF requiring a high burden of ventricular pacing. These results are only short term and need to be confirmed by further larger studies. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT06026683.

Reduction in new cardiac electronic device implantations in Catalonia during COVID-19.

AIMS: During the COVID-19 pandemic, concern regarding its effect on the management of non-communicable diseases has been raised. However, there are no data on the impact on cardiac implantable electronic devices (CIED) implantation rates. We aimed to determine the impact of SARS-CoV2 on the monthly incidence rates and type of pacemaker (PM) and implantable cardiac defibrillator (ICD) implantations in Catalonia before and after the declaration of the state of alarm in Spain on 14 March 2020. METHODS AND RESULTS: Data on new CIED implantations for 2017-20 were prospectively collected by nine hospitals in Catalonia. A mixed model with random intercepts corrected for time was used to estimate the change in monthly CIED implantations. Compared to the pre-COVID-19 period, an absolute decrease of 56.5% was observed (54.7% in PM and 63.7% in ICD) in CIED implantation rates. Total CIED implantations for 2017-19 and January and February 2020 was 250/month (>195 PM and >55 ICD), decreasing to 207 (161 PM and 46 ICD) in March and 131 (108 PM and 23 ICD) in April 2020. In April 2020, there was a significant fall of 185.25 CIED implantations compared to 2018 [95% confidence interval (CI) 129.6-240.9; P < 0.001] and of 188 CIED compared to 2019 (95% CI 132.3-243.7; P < 0.001). No significant differences in the type of PM or ICD were observed, nor in the indication for primary or secondary prevention. CONCLUSIONS: During the first wave of the COVID-19 pandemic, a substantial decrease in CIED implantations was observed in Catalonia. Our findings call for measures to avoid long-term social impact.

From High-Density Mapping to Low-Density Mapping: Outlining the Active Circuit in Complex Atrial Re-Entrant Tachycardias.

OBJECTIVES: The aim of this study was to describe a mapping approach for ablation of complex atrial re-entrant tachycardias (ARTs) in which high-density activation maps are transformed into low-density activation maps displaying only the active part of the tachycardia circuit. BACKGROUND: High-density activation maps during complex ARTs are challenging to interpret because they include the activation patterns of active and passive circuits. Entrainment mapping provides the identification of the active tachycardia circuit. However, current electroanatomic mapping systems are not capable of color-coding the information obtained from entrainment maneuvers. METHODS: Seventeen consecutive patients with atypical atrial flutter were included. A high-density activation map was acquired during index tachycardia. Subsequently, entrainment maneuvers were performed to generate a low-density activation map in which only the activation of the atria directly involved in the flutter circuit was displayed. RESULTS: Of all patients included, 82% were men, and their mean age was 62 ± 7 years. Structural heart disease was present in 59%, and 53% had undergone prior left atrial ablation procedures. Low-density activation maps were successfully generated from an average of 14 ± 3 entrainment points. Twenty circuits (95%) were identified in the left atrium and 1 (5%) in the right atrium. Ablation guided by low-density mapping successfully terminated all ARTs in 267 ± 353 s of radiofrequency application. CONCLUSIONS: Low-density mapping based on entrainment maneuvers provides a precise delineation of the active circuit during complex ARTs and resulted in successful arrhythmia termination. This approach can be easily incorporated into clinical practice.

Mapping potentials adjacent to the cavo-tricuspid isthmus ablation line during incremental pacing: A feasible and highly accurate maneuver to confirm complete CTI conduction block.

BACKGROUND: The diagnostic accuracy of incremental atrial pacing (IP) to determine complete cavo-tricuspid isthmus (CTI) block during typical atrial flutter (AFL) ablation is limited by both an extensive/nonlinear ablation and/or the presence of intra-atrial conduction delay elsewhere in the right atrium. We examined the diagnostic performance of an IP variant based on the assessment of the atrial potentials adjacent to the ablation line which aims at overcoming both limitations. METHODS: From a prospective population of 108 consecutive patients, 15 were excluded due to observation of inconclusive CTI ablation potentials precluding for a straight comparison between the IP maneuver and its variant. In the remaining 93, IP was performed from the low lateral right atrium and the coronary sinus ostium, with the ablation catheter positioned both at the CTI line and adjacent (<5 mm) to its septal and lateral aspect. The IP variant consisted of measuring the interval between the two atrial electrograms situated on the same side of the ablation line, opposite to the pacing site, a ≤10 ms increase indicating complete CTI block. RESULTS: The IP maneuver and its variant were consistent with complete CTI block in 82/93 (88%) and 87/93 (93%) patients, respectively. Four patients had AFL recurrence during follow-up: 2/4 and 4/4 had been adequately classified as incomplete block by the IP maneuver and its variant, respectively. Twenty-three patients (24%) had significant intra-atrial conduction delay elsewhere in the right atrium. The IP maneuver and its variant were suggestive of an incomplete CTI block in 11/23 and 4/23 in this setting (P = .028), with the later best predicting subsequent AFL relapses (2/12 vs 2/4, P = .01). CONCLUSIONS: The IP variant, which was designed to overcome the limitations of the conventional IP maneuver, accurately distinguishes complete from incomplete CTI block and helps to predict AFL recurrences after ablation.

Yield of atrial fibrillation detection with Textile Wearable Holter from the acute phase of stroke: Pilot study of Crypto-AF registry.

BACKGROUND: We describe the feasibility of monitoring with a Textile Wearable Holter (TWH) in patients included in Crypto AF registry. METHODS: We monitored cryptogenic stroke patients from stroke onset (<3days) continuously during 28days. We employed a TWH composed by a garment and a recorder. We compared two garments (Lead and Vest) to assess rate of undiagnosed Atrial Fibrillation (AF) detection, monitoring compliance, comfortability (1 to 5 points), skin lesions, and time analyzed. We describe the timing of AF detection in three periods (0-3, 4-15 and 16-28days). RESULTS: The rate of undiagnosed AF detection with TWH was 21.9% (32 out of 146 patients who completed the monitoring). Global time compliance was 90% of the time expected (583/644h). The level of comfortability was 4 points (IQR 3-5). We detected reversible skin lesions in 5.47% (8/146). The comfortability was similar but time compliance (in hours) was longer in Vest group 591 (IQR [521-639]) vs. Lead 566 (IQR [397-620]) (p=0.025). Also, time analyzed was more prolonged in Vest group 497 (IQR [419-557]) vs. Lead (336h (IQR [140-520]) (p=0.001)). The incidence of AF increases from 5.6% (at 3days) to 17.5% (at 15th day) and up to 20.9% (at 28th day). The percentage of AF episodes detected only in each period was 12.5% (0-3days); 21.7% (4-15days) and 19% (16-28days). CONCLUSIONS: 28days Holter monitoring from the acute phase of the stroke was feasible with TWH. Following our protocol, only five patients were needed to screen to detected one case of AF.

Safety and efficacy of in-hospital clopidogrel-to-prasugrel switching in patients with acute coronary syndrome. An analysis from the 'real world'.

Antiplatelet switching in the management of acute coronary syndrome (ACS) seems to be safe, but prospective data are limited. This retrospective study assessed the safety and efficacy of in-hospital clopidogrel-to-prasugrel switching in patients with ACS. We analysed 525 consecutive patients with ACS admitted to our coronary care unit. We assessed the prevalence and the short-term outcomes of in-hospital clopidogrel-to-prasugrel switching. Bleeding and thrombotic events were assessed using propensity score matching analysis. A total of 468 patients received acetylsalicylic acid and a P2Y12 ADP receptor inhibitor. Medication switching occurred in 117 patients (25 %). Compared with the clopidogrel group, the switching group consisted preferentially of younger males with STEMI, exhibited fewer comorbidities, and had lower ischaemic risk. We found no differences between the switching group and the clopidogrel group in the bleeding rate [3.6 vs. 2.3 %, odds ratio (OR):1.59 95 % confidence interval (CI): 0.26-9.7, p NS], and in adverse cardiac or cerebrovascular events (MACCE) (5 vs. 8.4 %, OR: 0.57 95 % CI 0.16-2, p NS). In-hospital switching from clopidogrel to prasugrel in a selected high-risk ACS population resulted in a similar incidence of in-hospital haemorrhagic and thrombotic events. This strategy should be clarified in further randomised studies.