The Lancet Commission to reduce the global burden of sudden cardiac death: a call for multidisciplinary action.

Despite major advancements in cardiovascular medicine, sudden cardiac death (SCD) continues to be an enormous medical and societal challenge, claiming millions of lives every year. Efforts to prevent SCD are hampered by imperfect risk prediction and inadequate solutions to specifically address arrhythmogenesis. Although resuscitation strategies have witnessed substantial evolution, there is a need to strengthen the organisation of community interventions and emergency medical systems across varied locations and health-care structures. With all the technological and medical advances of the 21st century, the fact that survival from sudden cardiac arrest (SCA) remains lower than 10% in most parts of the world is unacceptable. Recognising this urgent need, the Lancet Commission on SCD was constituted, bringing together 30 international experts in varied disciplines. Consistent progress in tackling SCD will require a completely revamped approach to SCD prevention, with wide-sweeping policy changes that will empower the development of both governmental and community-based programmes to maximise survival from SCA, and to comprehensively attend to survivors and decedents' families after the event. International collaborative efforts that maximally leverage and connect the expertise of various research organisations will need to be prioritised to properly address identified gaps. The Commission places substantial emphasis on the need to develop a multidisciplinary strategy that encompasses all aspects of SCD prevention and treatment. The Commission provides a critical assessment of the current scientific efforts in the field, and puts forth key recommendations to challenge, activate, and intensify efforts by both the scientific and global community with new directions, research, and innovation to reduce the burden of SCD worldwide.

Risk assessment of esophageal ulceration following left atrial radiofrequency linear ablation.

INTRODUCTION: Esophageal safety following radiofrequency (RF) left atrial (LA) linear ablation has not been established. To determine the esophageal safety profile of LA linear RF lesions, we performed systematic esophagogastroduodenoscopy in all patients with intraesophageal temperature rise (ITR) ≥ 38.5°C. METHODS AND RESULTS: Between December 2021 and July 2023, a total of 200 consecutive patients with atrial tachyarrhythmia (ATA) underwent linear ablation with posterior dome (roof or floor) or posterior mitral isthmus line transection. Patients with ITR ≥ 38.5°C were scheduled for esophageal endoscopy ~3 weeks after ablation. Patient and ATA characteristics, procedural parameters, endoscopy findings and ablation lesion data were collected and analyzed. One hundred thirty-three out of 200 (67%) patients showed ITR ≥ 38.5°C during LA linear ablation. ITR (with maximal temperature of 45.7°C) was more frequently observed during floor line ablation (82% of cases). ITR was less observed during roof line ablation (34%) and posterior mitral isthmus ablation (4%). Endoscopy, performed in 115 patients after 24 ± 10 days, showed esophageal ulceration in four patients (two patients Kansas City classification [KCC] 2a and two patients KCC 2b). No patient showed esophageal perforation or fistula. CONCLUSION: Temperature rise during LA linear ablation is frequent and ulceration risk exists, particularly when floor line is performed. Safety measures are needed to avoid potential severe complications like esophageal perforation and fistula.

Evaluation of posterior mitral isthmus ablation in the absence of a vein of Marshall.

BACKGROUND AND AIMS: Achieving acute and durable mitral isthmus (MI) block remains challenging using radio frequency (RF)-catheter ablation alone. Vein of Marshall (VoM) ethanolisation results in chemical damage along the mitral isthmus resulting in the creation of a durable transmural lesion with a very high rate of procedural block. However, no studies have systematically assessed the efficacy of MI ablation alone when no anatomical VoM is present. METHODS: Thirty seven patients without VoM evidenced after careful angiographic examination were included. Ablation parameters and result were compared to a matched control group in whom the posterior MI line was performed without assessing the presence of the VoM. RESULTS: MI block was achieved in 36 out of 37 patients without VoM (97%), with endocardial ablation only in 5/37 (14%) and combined endocardial and CS ablation in 32/37 patients (86%). There was a significant difference in occurrence of block between patients without a VoM and the control group (97,3% vs. 65% respectively, p<0,01), with a trend towards less needed RF (26 (IQR 20-38) vs 29 (IQR 19-40) tags (p=0.8), 611 (IQR 443-805) vs 746 (IQR 484-1193) seconds (p=0.08)). CONCLUSION: The absence of a Vein of Marshall is associated with a very high rate of procedural block during posterior mitral isthmus ablation. The higher rate of MI block in this specific population would also suggest the crucial role of the Vein of Marshall (when present) in resistant MI block.

Catheter Ablation of Persistent AF-Where are We Now?

Persistent atrial fibrillation (AF) is a diverse condition that includes various subtypes and underlying causes of arrhythmia. Progress made in catheter ablation technology in recent years has significantly enhanced the durability of ablation. Despite these advances however, the effectiveness of ablation in treating persistent AF is still relatively modest. Studies exploring the mechanisms behind persistent AF have identified substrate-driven focal and re-entrant sources within the atrial body as crucial in sustaining AF among individuals with persistent AF. Furthermore, the widespread adoption of atrial late gadolinium enhancement cardiac magnetic resonance (CMR) imaging and the ongoing refinement of invasive voltage mapping techniques have allowed for detailed assessment of fibrotic remodelling prior to or at the time of procedure. Translation into clinical practice, however, has yielded overall disappointing results. The clinical application of AF mapping in ablation procedures has not shown any substantial advantages beyond the use of pulmonary vein isolation (PVI) alone and adjunct ablation of fibrotic areas has yielded conflicting results in recent randomized trials. The emergence of pulsed field ablation represents a welcome development in the field and several studies have demonstrated an enhanced safety profile and increased procedural efficiency with this non-thermal energy modality. Pulsed field ablation also holds promise for safe and efficient substrate ablation beyond the pulmonary veins, but further trials are needed to assess its impact on longer term success rates. Continued advancements in our comprehension of AF mechanisms, alongside ongoing developments in catheter technology aimed at safe formation of transmural lesions, are essential for achieving better clinical outcomes for patients with persistent AF.

Left bundle branch area pacing guided by continuous uninterrupted monitoring of unipolar pacing characteristics.

INTRODUCTION: During left bundle branch area pacing (LBBAP) lead implantation, intermittent monitoring of unipolar pacing characteristics confirms LBB capture and can detect septal perforation. We aimed to demonstrate that continuous uninterrupted unipolar pacing from an inserted lead stylet (LS) is feasible and facilitates LBBAP implantation. METHODS: Thirty patients (mean age 76 ± 14 years) were implanted with a stylet-driven pacing lead (Biotronik Solia S60). In 10 patients (comparison-group) conventional implantation with interrupted unipolar pacing was performed, with comparison of unipolar pacing characteristics between LS and connector-pin (CP)-pacing after each rotation step. In 20 patients (uninterrupted-group) performance and safety of uninterrupted implantation during continuous pacing from the LS were evaluated. RESULTS: In the comparison group, LS and CP-pacing impedances were highly correlated (R2 = 0.95, p < .0001, bias 12 ± 37 Ω) with comparable sensed electrograms and paced QRS morphologies. In the uninterrupted group, continuous LS-pacing allowed beat-to-beat monitoring of impedance and QRS morphology to guide implantation. This resulted in successful LBBAP in all patients, after a mean of 1 ± 0 attempts, with mean threshold 0.81 ± 0.4 V, median sensing 6.5 mV [IQR 4.4-9.5], and mean impedance 624 ± 101 Ω. Positive LBBAP-criteria were seen in all patients with median paced QRS duration of 120 ms [IQR 112-152 ms] and median pLVAT 73 ms [IQR 68-80.5 ms]. No septal perforation occurred. CONCLUSION: Unipolar pacing from the LS allows accurate determination of pacing impedance and generates similar paced QRS morphologies and sensed electrograms to CP pacing. Continuous LS pacing allows real-time monitoring of impedance and paced QRS morphology, which facilitates safe and successful LBBAP lead implantation.

Initial experience of left bundle branch area pacing using stylet-driven pacing leads: A multicenter study.

BACKGROUND: Left bundle branch area pacing (LBBAP) has been performed exclusively using lumen-less pacing leads (LLL) with fixed helix design. This registry study explores the safety and feasibility of LBBAP using stylet-driven leads (SDL) with extendable helix design in a multicenter patient population. METHODS: This study prospectively enrolled consecutive patients who underwent LBBAP for bradycardia pacing or heart failure indications at eight Belgian hospitals. LBBAP was attempted using SDL (Solia S60; Biotronik) delivered through dedicated delivery sheath (Selectra3D). Implant success, complications, procedural, and pacing characteristics were recorded at implant and follow-up. RESULTS: The study enrolled 353 patients (mean age 76 ± 39 years, 43% female). The mean number of implants per center was 25 (range: 5-162). Overall, LBBAP with SDL was successful in 334/353 (94%), varying from 93% to 100% among centers. Pacing response was labeled as left bundle branch pacing in 73%, whereas 27% were labeled as myocardial capture. Mean paced QRS duration and stimulus to left ventricular activation time measured 126 ± 21 ms and 74 ± 17. SDL-LBBAP resulted in low pacing thresholds (0.6 ± 0.4 V at 0.4 ms), which remained stable at 12 months follow-up (0.7 ± 0.3, p = .291). Lead revisions for SDL-LBBAP occurred in 5 (1.4%) patients occurred during a mean follow up of 9 ± 5 months. Five (1.4%) septal coronary artery fistulas and 8 (2%) septal perforations occurred, none of them causing persistent ventricular septal defects. CONCLUSION: The use of SDL to achieve LBBAP is safe and feasible, characterized by high implant success in low and high volume centers, low complication rates, and stable low pacing thresholds.

Safety of very high-power short-duration radiofrequency ablation for pulmonary vein isolation: a two-centre report with emphasis on silent oesophageal injury.

AIMS: Very high-power short-duration (vHPSD) via temperature-controlled ablation (TCA) is a new modality to perform radiofrequency pulmonary vein isolation (PVI), conceivably at the cost of a narrower safety margin towards the oesophagus. In this two-centre trial, we aimed to determine the safety of vHPSD-based PVI with specific emphasis on silent oesophageal injury. METHODS AND RESULTS: Ninety consecutive patients with atrial fibrillation (AF) underwent vHPSD-PVI (90 W, 3-4 s, TCA) using the QDOT MICRO catheter, in conjunction with the nGEN (Bad Neustadt, n = 45) or nMARQ generator (Bruges, n = 45). All patients underwent post-ablation oesophageal endoscopy. Procedural parameters and complications were recorded. A subgroup of 21 patients from Bad Neustadt underwent cerebral magnetic resonance imaging (cMRI) to detect silent cerebral events (SCEs). Mean age was 67 ± 9 years, 59% patients were male, and 66% patients had paroxysmal AF. Pulmonary vein isolation was obtained in all cases after 96 ± 29 min. No steam pop, cardiac tamponade, stroke, or fistula was reported. None of the 90 patients demonstrated oesophageal ulceration (0%). Charring was not observed in the nMARQ cohort (0% vs. 11% in the nGEN group). In 5 out of 21 patients (24%), cMRI demonstrated SCE (exclusively nGEN cohort). CONCLUSION: Temperature-controlled vHPSD catheter ablation allows straightforward PVI without evidence of oesophageal ulcerations or symptomatic complications. Catheter tip charring and silent cerebral lesions when using the nGEN generator have led to further modification.

Repositioning and extraction of stylet-driven pacing leads with extendable helix used for left bundle branch area pacing.

Conventional stylet-driven leads with extendable helix can be implanted successfully for left bundle branch area pacing (LBBAP) with a low acute complication rate. We report two cases in which lead repositioning after a first unsuccessful attempt to LBBAP was associated with fracture of the helix rotating mechanism and failure to fully extract the pacing lead.

Influence of sympathetic activation on myocardial contractility measured with ballistocardiography and seismocardiography during sustained end-expiratory apnea.

Ballistocardiography (BCG) and seismocardiography (SCG) assess vibrations produced by cardiac contraction and blood flow, respectively, through micro-accelerometers and micro-gyroscopes. BCG and SCG kinetic energies (KE) and their temporal integrals (iK) during a single heartbeat are computed in linear and rotational dimensions. Our aim was to test the hypothesis that iK from BCG and SCG are related to sympathetic activation during maximal voluntary end-expiratory apnea. Multiunit muscle sympathetic nerve traffic [burst frequency (BF), total muscular sympathetic nerve activity (tMSNA)] was measured by microneurography during normal breathing and apnea (n = 28, healthy men). iK of BCG and SCG were simultaneously recorded in the linear and rotational dimension, along with oxygen saturation ([Formula: see text]) and systolic blood pressure (SBP). The mean duration of apneas was 25.4 ± 9.4 s. SBP, BF, and tMSNA increased during the apnea compared with baseline (P = 0.01, P = 0.002,and P = 0.001, respectively), whereas [Formula: see text] decreased (P = 0.02). At the end of the apnea compared with normal breathing, changes in iK computed from BCG were related to changes of tMSNA and BF only in the linear dimension (r = 0.85, P < 0.0001; and r = 0.72, P = 0.002, respectively), whereas changes in linear iK of SCG were related only to changes of tMSNA (r = 0.62, P = 0.01). We conclude that maximal end expiratory apnea increases cardiac kinetic energy computed from BCG and SCG, along with sympathetic activity. The novelty of the present investigation is that linear iK of BCG is directly and more strongly related to the rise in sympathetic activity than the SCG, mainly at the end of a sustained apnea, likely because the BCG is more affected by the sympathetic and hemodynamic effects of breathing cessation. BCG and SCG may prove useful to assess sympathetic nerve changes in patients with sleep disturbances.NEW & NOTEWORTHY Ballistocardiography (BCG) and seismocardiography (SCG) assess vibrations produced by cardiac contraction and blood flow, respectively, through micro-accelerometers and micro-gyroscopes. Kinetic energies (KE) and their temporal integrals (iK) during a single heartbeat are computed from the BCG and SCG waveforms in a linear and a rotational dimension. When compared with normal breathing, during an end-expiratory voluntary apnea, iK increased and was positively related to sympathetic nerve traffic rise assessed by microneurography. Further studies are needed to determine whether BCG and SCG can probe sympathetic nerve changes in patients with sleep disturbances.

His bundle pacing for newly acquired pacing needs in patients implanted with a subcutaneous implantable cardioverter defibrillator: A feasibility study based on the automated screening score and clinical cases.

INTRODUCTION: Management of subcutaneous implantable cardioverter defibrillator (S-ICD) patients with newly acquired pacing needs remains problematic. His bundle pacing (HBP) allows for cardiac pacing without significant changes in the QRS morphology. We hypothesized that HBP does not alter S-ICD sensing and functions. METHODS: Twenty consecutive patients were implanted with a HB pacemaker. Among them, 17 demonstrated successful His recruitment and were prospectively screened with the automated screening tool (AST). Results of screenings performed immediately after implant and during follow-up, during intrinsic rhythm and while pacing from all available pacing configurations, were compared using the AST score. Positive-screening tests were defined by greater than or equal to 1 positive vector. RESULTS: Among the 17 patients successfully implanted (male: 41%; mean age: 73), 13 presented an indication of ventricular pacing and four of cardiac resynchronization. Absolute AST scores during both HBP (all configurations) and intrinsic rhythm were similar (p: NS). Due to left bundle branch block correction, HBP resulted in higher number of positive vectors (AST ≥ 100). AST scores were higher during HBP when compared with right ventricular pacing (RVP) (primary vector: 272 [16; 648] vs 4.6 [0.8; 16.2]; P = .003; secondary vector: 569 [183; 1186] vs 1.5 [0.7; 8.3]; P < .0001; alternate vector: 44 [2;125] vs 4.8 [0.9; 9.3]; P = .02) and resulted in a much higher number of positive vectors. Up to 90% of the patients had a positive-screening test during HBP. This passing rate was higher when compared RVP (17%; P < .0001). CONCLUSION: HBP restores normal intrinsic conduction and minimally modifies the surface electrocardiograph and subcutaneous electrograms. When ventricular pacing is needed, HBP might represent an ideal pacing option for patients implanted with a S-ICD.

Impact of paced left ventricular dyssynchrony on left ventricular reverse remodeling after cardiac resynchronization therapy.

INTRODUCTION: We investigated whether pacing-induced electrical dyssynchrony at the time of cardiac resynchronization therapy (CRT) device implantation was associated with chronic CRT response. METHODS AND RESULTS: We included a total of 69 consecutive heart failure patients who received a CRT device. Left (LVp-RVs) and right (RVp-LVs) pacing-induced interlead delays were measured intraoperatively and used to determine if there was paced left ventricular (LV) dyssynchrony, defined as present when LVp-RVs is larger than RVp-LVs. CRT response was defined as a reduction in LV end-systolic volume ≥15%, 6 months after implantation. Paced left ventricular dyssynchrony (PLVD) was associated with ischemic cardiomyopathy (ICM) (χ2 : 8; P = .005) but not with QRS morphology nor with pacing lead positions. In a univariate analysis, PLVD (odds ratio [OR], 6.53; 95% confidence interval [CI], 2.2-18.9; P = .001), atypical left bundle branch block (LBBB) (OR, 3.3; 95% CI, 1.2-9.4; P = .022), and ICM (OR, 5.2; 95% CI, 1.6-17; P = .006) were associated with nonresponse. In a multivariate analysis, both PLVD (OR, 9.74; 95% CI, 2.8-33.9; P < .0001) and atypical LBBB (OR, 5.6; 95% CI, 1.5-20.3; P = .009) were independently associated with nonresponse. Adding PLVD to a model based on QRS morphology provided a significant and meaningful incremental value to predict LV reverse remodeling after CRT (χ2 to enter: 8; P < .005). Computer simulations corroborate these findings by showing that, while intrinsic electrical dyssynchrony is a prerequisite, the level of pacing-induced dyssynchrony modulates acute CRT response. CONCLUSION: In addition to the intrinsic electrical substrate, PLVD is strongly associated with less LV reverse remodeling, demonstrating that measuring the electrical substrate during pacing has additional value for prediction of CRT response in an already well-selected patient population.

Feasibility of His-bundle pacing in patients with conduction disorders following transcatheter aortic valve replacement.

BACKGROUND: Conduction disorders requiring permanent pacemaker implantation occur frequently after transcatheter aortic valve replacement (TAVR). This multicenter study explored the feasibility and safety of His bundle pacing (HBP) in TAVR patients with a pacemaker indication to correct a TAVR-induced left bundle branch block (LBBB). METHODS: Patients qualifying for a permanent pacemaker implant after TAVR were planned for HBP implant. HBP was performed using the Select Secure (3830; Medtronic) pacing lead, delivered through a fixed curve or deflectable sheath (C315HIS or C304; Medtronic). Successful HBP was defined as selective or nonselective HBP, irrespective of LBB recruitment. Successful LBBB correction was defined as selective or nonselective HBP resulting in paced QRS morphology similar to pre-TAVR QRS and paced QRS duration (QRSd) less than 120 milliseconds with thresholds less than 3.0 V at 1.0-millisecond pulse width. RESULTS: The study enrolled 16 patients requiring a permanent pacemaker after TAVR (age 85 ± 4 years, 31% female, all LBBB; QRSd: 161 ± 14 milliseconds). Capture of the His bundle was achieved in 13 of 16 (81%) patients. HBP with LBBB correction was achieved in 11 of 16 (69%) and QRSd narrowed from 162 ± 14 to 99 ± 13 milliseconds and 134 ± 7 milliseconds during S-HBP and NS-HBP, respectively (P = .005). At implantation, mean threshold for LBBB correction was 1.9 ± 1.1 V at 1.0 millisecond. Thresholds remained stable at 11 ± 4 months follow-up (1.8 ± 0.9 V at 1.0 millisecond, P = .231 for comparison with implant thresholds). During HBP implant, one temporary complete atrioventricular block occurred. CONCLUSION: Permanent HBP is feasible in the majority of patients with TAVR requiring a permanent pacemaker with the potential to correct a TAVR-induced LBBB with acceptable pacing thresholds.

Quality assessment in Belgian arrhythmology: the Belgian heart rhythm association (BeHRA) databases.

This report presents and discusses, on behalf of the Belgian College of Cardiology, the evolution of the peer review process in arrhythmology, focussing on pacemaker implantation. Data from the last 22 years are compared. The national annual increase in implants is around 1%, clinical patient characteristics remained stable over the years while dual chamber pacing was proportionally increasing. Analyses of the normalised sick sinus and complete atrioventricular block ratios revealed a quite homogenous practice between centres and patient district with the only exception of the two more crowded districts. Battery longevity and infection rate were also assessed. With an incidence of 1/1000 device-years follow-up, Belgium remains below accepted European levels.

Long-term prognosis of patients with life-threatening ventricular arrhythmias induced by coronary artery spasm.

Aims: Coronary artery spasm (CAS) is associated with ventricular arrhythmias (VA). Much controversy remains regarding the best therapeutic interventions for this specific patient subset. We aimed to evaluate the clinical outcomes of patients with a history of life-threatening VA due to CAS with various medical interventions, as well as the need for ICD placement in the setting of optimal medical therapy. Methods and results: A multicentre European retrospective survey of patients with VA in the setting of CAS was aggregated and relevant clinical and demographic data was analysed. Forty-nine appropriate patients were identified: 43 (87.8%) presented with VF and 6 (12.2%) with rapid VT. ICD implantation was performed in 44 (89.8%). During follow-up [59 (17-117) months], appropriate ICD shocks were documented in 12. In 8/12 (66.6%) no more ICD therapies were recorded after optimizing calcium channel blocker (CCB) therapy. SCD occurred in one patient without ICD. Treatment with beta-blockers was predictive of appropriate device discharge. Conversely, non-dihydropyridine CCB therapy was significantly protective against VAs. Conclusion: Patients with life-threatening VAs secondary to CAS are at particularly high-risk for recurrence, especially when insufficient medical therapy is administered. Non-dihydropyridine CCBs are capable of suppressing episodes, whereas beta-blocker treatment is predictive of VAs. Ultimately, in spite of medical intervention, some patients exhibited arrhythmogenic events in the long-term, suggesting that ICD implantation may still be indicated for all.

Interest of waiting time for spontaneous early reconnection after cavotricuspid isthmus ablation: A monocentric randomized trial.

INTRODUCTION: The aim of this study was to determine the rate of recurrent atrial flutter (AFl) after isolated cavotricuspid isthmus (CTI) ablation and to evaluate the impact of a waiting period with the search for early resumption of the CTI block on the long-term outcome. METHOD: Three hundred and nineteen consecutive patients referred for typical AFl ablation were randomly assigned to CTI ablation with continuous reevaluation of the CTI block during 30 minutes and early reablation if needed (waiting time [WT] + group, n  =  155) or to CTI ablation with no waiting period after proven bidirectional CTI block (WT - group, n  =  164). All patients were regularly followed-up. RESULT: In the WT+ group, 10 patients (6%) presented a recovery across the CTI (time to recovery: 17 ± 7') and were reablated at the end of the waiting period. After a median follow-up of 21 months, the rate of recurrent AFl was significantly higher in the WT - group as compared to the WT+ group (11.6% [19/164] vs 2.5% [4/155], respectively; P  =  0.007). However, no significant differences in the subsequent rate of AF were observed between the two groups (29% [WT -] vs 32% [WT+], P  =  0.66). During the follow-up, 28 patients from the WT - group underwent a second ablation procedure (16 AFl redo and 12 AF ablation) versus 10 patients form the WT+ group (three AFl redo and seven AF ablation). CONCLUSION: Waiting 30 minutes after CTI ablation to check for early resumption and early reablation allows for decreasing significantly the rate of recurrent atrial flutter.

Low contact force and force-time integral predict early recovery and dormant conduction revealed by adenosine after pulmonary vein isolation.

AIM: After pulmonary vein isolation (PVI), dormant conduction (DC) is present in at least one vein in a substantial number of patients. The present study seeks to determine whether there is a relationship between poor contact forces (CF) and the presence of DC after PVI. METHODS AND RESULTS: This prospective, operator-blinded, non-randomized dual-centre trial enrolled 34 consecutive patients with paroxysmal atrial fibrillation who were candidates for PVI. Radiofrequency (RF) energy was delivered by using an irrigated-tip force-sensing ablation catheter (Tacticath, St Jude Medical) at pre-defined target power. The operators were blinded to the CF data at all times. A total of 1476 RF applications were delivered in 743 pre-defined PV segments. For each application, the precise location of the catheter was registered and the following data were extracted from the Tacisys unit: application duration, minimum contact force, maximum contact force, average contact force (CF), and force-time integral (FTI). Sixty minutes after PVI, spontaneous early recovery (ER) of the left atrium (LA) to PV conduction was evaluated. In the absence of ER, the presence of a DC was evaluated by using intravenous adenosine (ATP). In the 34 patients recruited (23 males; mean age: 62 ± 9 years), all PVs were successfully isolated. At the end of the 60 min waiting period, 22 patients demonstrated at least one spontaneous ER or DC under ATP. The mean CF and FTI per PV segment differed significantly among the different veins but the sites of ER and DC were evenly distributed. However, both the minimum, the first and the mean CF and FTI per PV segment were significantly lower in the PV segments presenting either ER or DC as compared with those without ER or DC (mean CF: 4.9 ± 4.8 vs. 12.2 ± 1.65 g and mean FTI: 297 ± 291 vs. 860 ± 81 g s, P < 0.001 for both). Using multivariate analysis, both the mean CF and the FTI per lesion remained significantly associated with the risk of ER or DC. Moreover, a CF < 5 g per PV segment predicted ER+ and DC+ with a sensitivity of 71% and specificity of 82%. In contrast, ER and DC were very unlikely if RF application was performed with a mean CF > 10 g (negative predictive value: 98.7%). CONCLUSION: Both a low CF and a low FTI are associated with the ER of the PVI and DC after PVI.

Evaluation of a new semiautomated external defibrillator technology: a live cases video recording study.

AIM: To determine the effect of a new automated external defibrillator (AED) system connected by General Packet Radio Service (GPRS) to an external call centre in assisting novices in a sudden cardiac arrest situation. METHOD: Prospective, interventional study. Layperson volunteers were first asked to complete a survey about their knowledge and ability to give cardiopulmonary resuscitation (CPR) and use an AED. A simulated cardiac arrest scenario using a CPR manikin was then presented to volunteers. A telephone and semi-AED were available in the same room. The AED was linked to a call centre, which provided real-time information to 'bystanders' and emergency services via GPRS/GPS technology. The scene was videotaped to avoid any interaction with examiners. A standardised check list was used to record correct actions. RESULTS: 85 volunteers completed questionnaires and were recorded. Mean age was 44±16, and 49% were male; 38 (45%) had prior CPR training or felt comfortable intervening in a sudden cardiac arrest victim; 40% felt they could deliver a shock using an AED. During the scenarios, 56 (66%) of the participants used the AED and 53 (62%) successfully delivered an electrical shock. Mean time to defibrillation was 2 min 29 s. Only 24 (28%) participants dialled the correct emergency response number (112); the live-assisted GPRS AED allowed alerted emergency services in 38 other cases. CPR was initiated in 63 (74%) cases, 26 (31%) times without prompting and 37 (44%) times after prompting by the AED. CONCLUSIONS: Although knowledge of the general population appears to be inadequate with regard to AED locations and recognition, live-assisted devices with GPS-location may improve emergency care.

Predictive value of the heart rate reserve in patients with permanent atrial fibrillation treated according to a strict rate-control strategy.

AIMS: Atrial fibrillation (AF) patients treated according to a rate-control strategy seem to have excellent outcomes as long as their ventricular response is kept low. However, the stringency of the rate control to adopt with pharmacologic agents is not clearly defined. In particular, the clinical importance of preserving a heart rate (HR) reserve (HRR) during exercise has not yet been investigated. METHODS AND RESULTS: We prospectively analysed the HR response profiles during exercise of 202 patients with permanent AF for whom a strict rate-control strategy was the preferred treatment option. Patients were asked to perform an exercise test on a cycle ergometer until exhaustion. The HRR was defined as the difference between the HR at peak exercise and the resting HR before exercise, divided by the resting HR. Patients were followed-up for at least 24 months or until death or hospitalization for heart failure. The mean resting HR was 80 ± 16 b.p.m. After a median follow-up period of 3 ± 1 years, 31 patients (15.3%) of our initial population (80% male, age 72 ± 12 years) presented either a hospitalization for heart failure (n = 13, 6.4%) or a death (n = 18, 8.9%). Using a univariate analysis, we found that these events correlated with a lower exercise capacity [hazard ratio, HR 0.98, 95% confidence interval, CI (0.96; 0.99), P < 0.001] and a lower HRR [HR 0.30, 95% CI (0.15; 0.60), P < 0.001]. Using a multivariate analysis, both the exercise capacity [HR 0.98, 95% CI (0.97; 0.99), P = 0.008] and the HRR [HR 0.42, 95% CI (0.20-0.87), P = 0.02] remained significantly associated with the outcome. In particular, 4-year survival free from hospitalization for heart failure was better in patients with a preserved HRR (HRR >40%, P < 0.001). No correlation was found between the treatment category (i.e. beta-blockers, calcium channel antagonist, and digoxin) and the HRR. CONCLUSION: An impaired HRR in patients with permanent AF treated according to a strict rate-control strategy is associated with an increased risk of hospitalization for heart failure.

Rescue retrograde coronary venous ethanol ablation of ventricular tachycardia storm in a patient with Lamin A/C cardiomyopathy: a case report.

Background: Left ventricular (LV) summit arrhythmias account for up to 14% of LV arrhythmias. The ablation of LV summit arrhythmias is challenging, as testified by the fact that radiofrequency (RF) catheter ablation failure is frequent. Retrograde coronary venous ethanol infusion has been proposed as an alternative approach for the ablation of LV summit arrhythmias. Case summary: A 47-year-old man with Lamin A/C cardiomyopathy was referred for the ablation of a pleiomorphic ventricular tachycardia (VT) storm, with dominant morphology compatible with LV summit origin. He first received a combined endo- and epicardial RF ablation with the elimination of three clinically relevant VTs. However, the dominant VT could not be ablated due to the proximity of the coronary vasculature and phrenic nerve and remained inducible. Accordingly, an urgent rescue redo procedure consisting of retrograde coronary venous ethanol ablation was performed. Based on the best pace-match and precocity, the first septal, retro-pulmonary branch and the first diagonal branch were infused with ethanol with immediate cessation of the tachycardia and non-inducibility. Anti-arrhythmic drugs were withdrawn, while guideline-directed medical therapy for heart failure was continued. No complications occurred. After 3 months, the patient remained free from any arrythmias. Discussion: Ablation of LV summit arrythmias is challenging, especially in the context of an electrical storm or in patients with structural heart disease. In such a situation, rescue ablation with retrograde coronary venous ethanol infusion represents an attractive alternative ablation modality.