Outcome of Temporary Circulatory Support As a Bridge-to-Left Ventricular Assist Device Strategy in Cardiogenic Shock Patients.

OBJECTIVES: Temporary circulatory support (TCS) as a bridge-to-left ventricular assist device (BTL) in cardiogenic shock patients has been increasing, but limited data exists on this BTL strategy. We aimed at analyzing the outcome of BTL patients in a population of cardiogenic shock patients compared with those without TCS at the time of the left ventricular assist device (LVAD) surgery and identify predictors of postoperative mortality in this specific population. DESIGN: A multicenter retrospective observational study conducted in 19 centers from 2006 to 2016. SETTING: Nineteen French centers. PATIENTS: A total of 329 cardiogenic shock patients at the time of LVAD implantation were analyzed. Patients were divided in three groups: those under TCS at the time of LVAD implantation (n = 173), those with TCS removal before LVAD surgery (n = 24), and those who did not undergo a bridging strategy (n = 152). Primary endpoint was 30-day mortality. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Among the BTL group, 68 (39.3%), 18 (10.4%), and 15 (8.7%) patients were under venoarterial extracorporeal membrane oxygenation, Impella, and IABP support alone, and 72 patients (20.6%) were under multiple TCS support. BTL patients presented similar 30 days survival compared with the TCS removal and non-BTL groups. However, BTL group had a significantly longer ICU duration stay, with two-fold duration of mechanical ventilation time, but the three groups experienced similar postoperative complications. Multivariate analysis identified three independent predictors of mortality in the BTL group: combined surgery with LVAD, body mass index (BMI), and heart failure (HF) duration. BTL strategy was not an independent predictor of mortality in cardiogenic shock patients who underwent LVAD. CONCLUSIONS: BTL strategy is not associated with a lower survival among cardiogenic shock patients with LVAD implantation. Predictors of mortality are combined surgery with LVAD, higher BMI, and HF duration.

Atrial fibrillation evolution and rhythm control strategy following left appendage closure: new insights from the prospective FLAAC registry.

BACKGROUND: Percutaneous left atrial appendage (LAA) closure is an alternative to oral anticoagulation (OAC) for atrial fibrillation (AF) patients with high thromboembolism risk, particularly with contraindications to OAC. The LAA itself could possess proarrhythmogenic properties. As patients undergoing LAA closure could be candidates for cardioversion or ablation, we aimed to evaluate AF disease progression following LAA closure and the outcome of patients undergoing a rhythm control strategy after the procedure. METHODS: The prospective multicenter French Nationwide Observational LAA Closure Registry (FLAAC) comprises 33 French interventional cardiology departments. Patients were included if they fulfilled the following criteria: history of non-valvular AF, successful LAA closure and long-term ECG follow-up. RESULTS: A total of 331 patients with successful LAA closure were enrolled in the study. Patients mean age was 75.4 ± 0.5 years. The study population was characterized by a high thromboembolic risk (CHA2DS2-VASc score: 4.5 ± 0.1) and frequent comorbidities. The median follow-up was 11.9 months. One hundred and nineteen (36.0%) patients were in sinus rhythm (SR) at baseline. Among SR patients, documented AF was observed in 16 (13.4%) patients whereas 15 (7.1%) patients in AF at baseline restored SR, at the end of follow up. Finally, only 13 patients (4%) underwent procedures to restore SR without complications during the follow-up. CONCLUSIONS: The vast majority of patients undergoing LAA closure have the same AF status at baseline and one year after the index procedure. During the follow-up, a very small proportion (4%) of our population underwent procedures to restore SR without complications whatever the post-procedural antithrombotic strategy was.

Implantable cardiac defibrillator leads dysfunction after LVAD implantation.

BACKGROUND: Implantable cardioverter-defibrillator (ICD) lead dysfunction has been reported after left ventricular assist device (LVAD) implantation in limited single-center studies. We aimed at describing and characterizing the incidence of ICD lead parameters dysfunction after LVAD implantation. METHODS: Among the 652 patients enrolled in the ASSIST-ICD study, only patients with an ICD prior to LVAD were included (n = 401). ICD lead parameters dysfunction following LVAD implantation is defined as follows: (a) >50% decrease in sensing threshold, (b) pacing lead impedance increase/decrease by >100Ω, and (c) >50% increase in pacing threshold. RESULTS: One hundred twenty-two patients with an ICD prior to LVAD had available ICD interrogation reports prior and after LVAD. A total of 67 (55%) patients exhibited at least one significant lead dysfunction: 17 (15%) exhibited >50% decrease in right ventricular (RV) sensing, 51 (42%) had >100 Ω increase/decrease in RV pacing impedance, and 24 (20%) experienced >50% increase in RV pacing threshold. A total of 52 patients experienced ventricular arrhythmia during follow-up and all were successfully detected and treated by the device. All lead dysfunction could be managed conservatively. CONCLUSION: More than 50% of LVAD-recipients may experience >1 significant change in lead parameters but none had severe clinical consequences.

Risk factors and prognostic impact of left ventricular assist device-associated infections.

BACKGROUND: Left ventricular assist device (LVAD)-associated infections may be life-threatening and impact patients' outcome. We aimed to identify the characteristics, risk factors, and prognosis of LVAD-associated infections. METHODS: Patients included in the ASSIST-ICD study (19 centers) were enrolled. The main outcome was the occurrence of LVAD-associated infection (driveline infection, pocket infection, or pump/cannula infection) during follow-up. RESULTS: Of the 652 patients enrolled, 201 (30.1%) presented a total of 248 LVAD infections diagnosed 6.5 months after implantation, including 171 (26.2%), 51 (7.8%), and 26 (4.0%) percutaneous driveline infection, pocket infection, or pump/cannula infection, respectively. Patients with infections were aged 58.7 years, and most received HeartMate II (82.1%) or HeartWare (13.4%). Most patients (62%) had implantable cardioverter-defibrillators (ICDs) before LVAD, and 104 (16.0%) had ICD implantation, extraction, or replacement after the LVAD surgery. Main pathogens found among the 248 infections were Staphylococcus aureus (n = 113' 45.4%), Enterobacteriaceae (n = 61; 24.6%), Pseudomonas aeruginosa (n = 34; 13.7%), coagulase-negative staphylococci (n = 13; 5.2%), and Candida species (n = 13; 5.2%). In multivariable analysis, HeartMate II (subhazard ratio, 1.56; 95% CI, 1.03 to 2.36; P = .031) and ICD-related procedures post-LVAD (subhazard ratio, 1.43; 95% CI, 1.03-1.98; P = .031) were significantly associated with LVAD infections. Infections had no detrimental impact on survival. CONCLUSIONS: Left ventricular assist device-associated infections affect one-third of LVAD recipients, mostly related to skin pathogens and gram-negative bacilli, with increased risk with HeartMate II as compared with HeartWare, and in patients who required ICD-related procedures post-LVAD. This is a plea to better select patients needing ICD implantation/replacement after LVAD implantation.

Premature ventricular contraction diurnal profiles predict distinct clinical characteristics and beta-blocker responses.

INTRODUCTION: Frequent premature ventricular complexes (PVCs) can lead to symptoms, such as cardiomyopathy and increased mortality. Beta-blockers are recommended as first-line therapy to reduce PVC burden; however, the response is unpredictable. The objective of this study is to determine whether PVC diurnal-variability patterns are associated with different clinical profiles and predict drug response. METHODS: Consecutive patients with frequent PVCs (burden ≥ 1%), referred for Holter monitoring between 2014 and 2016, were included. Follow-up Holters, when available, were assessed after beta-blocker initiation to assess response (≥50% reduction). Patients were divided into three groups on the basis of relationship between hourly PVC count and mean HR during each of the 24 Holter hours: (1) fast-HR-dependent-PVC (F-HR-PVC) for positive correlation (Pearson, P < 0.05), (2) slow-HR-dependent-PVC (S-HR-PVC) for a negative, and (3) independent-HR-PVC (I-HR-PVC) when no correlation was found. RESULTS: Of the 416 patients included, 50.2% had F-HR-PVC, 35.6% I-HR-PVC, and 14.2% S-HR-PVC with distinct clinical profiles. Beta-blocker therapy was successful in 34.0% patients overall: patients with F-HR-PVC had a decrease in PVC burden (18.8 ± 10.4% to 9.3 ± 6.6%, P < 0.0001; 62% success), I-HR-PVC had no change (18.4 ± 17.9% to 20.6 ± 17.9%, P = 0.175; 0% success), whereas S-HR-PVC had an increase in burden (14.6 ± 15.3% to 20.8 ± 13.8%, P = 0.016; 0% success). The correlation coefficient was the only predictor of beta-blocker success (AUC = 0.84, sensitivity = 100%, specificity = 67.7%; r ≥ 0.4). CONCLUSIONS: A simple analysis of Holter PVC diurnal variability may provide incremental value to guide clinical PVC management. Only patients displaying a F-HR-PVC profile benefited from beta-blockers. An alternative strategy should be considered for others, as beta-blockers may have no effect or can even be harmful.

Cardiac sympathetic innervation via middle cervical and stellate ganglia and antiarrhythmic mechanism of bilateral stellectomy.

Cardiac sympathetic denervation (CSD) is reported to reduce the burden of ventricular tachyarrhythmias [ventricular tachycardia (VT)/ventricular fibrillation (VF)] in cardiomyopathy patients, but the mechanisms behind this benefit are unknown. In addition, the relative contribution to cardiac innervation of the middle cervical ganglion (MCG), which may contain cardiac neurons and is not removed during this procedure, is unclear. The purpose of this study was to compare sympathetic innervation of the heart via the MCG vs. stellate ganglia, assess effects of bilateral CSD on cardiac function and VT/VF, and determine changes in cardiac sympathetic innervation after CSD to elucidate mechanisms of benefit in 6 normal and 18 infarcted pigs. Electrophysiological and hemodynamic parameters were evaluated at baseline, during bilateral stellate stimulation, and during bilateral MCG stimulation in 6 normal and 12 infarcted animals. Bilateral CSD (removal of bilateral stellates and T2 ganglia) was then performed and MCG stimulation repeated. In addition, in 18 infarcted animals VT/VF inducibility was assessed before and after CSD. In infarcted hearts, MCG stimulation resulted in greater chronotropic and inotropic response than stellate ganglion stimulation. Bilateral CSD acutely reduced VT/VF inducibility by 50% in infarcted hearts and prolonged global activation recovery interval. CSD mitigated effects of MCG stimulation on dispersion of repolarization and T-peak to T-end interval in infarcted hearts, without causing hemodynamic compromise. These data demonstrate that the MCG provides significant cardiac sympathetic innervation before CSD and adequate sympathetic innervation after CSD, maintaining hemodynamic stability. Bilateral CSD reduces VT/VF inducibility by improving electrical stability in infarcted hearts in the setting of sympathetic activation.NEW & NOTEWORTHY Sympathetic activation in myocardial infarction leads to arrhythmias and worsens heart failure. Bilateral cardiac sympathetic denervation reduces ventricular tachycardia/ventricular fibrillation inducibility and mitigates effects of sympathetic activation on dispersion of repolarization and T-peak to T-end interval in infarcted hearts. Hemodynamic stability is maintained, as innervation via the middle cervical ganglion is not interrupted.

Use of adenosine to shorten the post ablation waiting period for cavotricuspid isthmus-dependent atrial flutter.

BACKGROUND: Dormant conduction unmasked by adenosine predicts clinical recurrences of cavotricuspid isthmus (CTI) dependent atrial flutter following catheter ablation. Conventional practice involves a waiting period of 20 to 30 minutes after achievement of a bidirectional line of block (BDB) to monitor for recovery of conduction. OBJECTIVE: Assess whether abolition of dormant conduction with adenosine immediately after CTI ablation and BDB can predict the lack of CTI conduction recovery during the following 30 minutes. METHODS: Consecutive patients undergoing catheter ablation for CTI-dependent atrial flutter were studied. Following the completion of CTI ablation and documentation of BDB, adenosine (≥12 mg IV) was administered immediately. In cases of dormant conduction, the CTI was ablated again until its abolition. After the achievement of BDB without dormant conduction, spontaneous CTI reconnection during the following 30 minutes and dormant conduction with adenosine at 30 minutes were evaluated. RESULTS: A CTI block was achieved in 171 patients. Nine patients (5.3%) had dormant conduction across the CTI immediately after ablation and BDB, and required further ablation. Two patients (1.2%) had subsequent spontaneous time-dependent reconnection within 30 minutes. Two other patients (1.2%) developed late dormant conduction with adenosine at 30 minutes. All 4 patients underwent further ablation. CONCLUSION: A negative adenosine challenge immediately after CTI ablation with bidirectional block, or after abolition of dormant conduction with further ablation, strongly predicted the absence of subsequent spontaneous reconnection within 30 minutes. Based on these results, the conventional waiting period is unnecessary in 97.6% patients without dormant conduction after CTI-dependent flutter ablation.

A New Combined Parameter to Predict Premature Ventricular Complexes Induced Cardiomyopathy: Impact and Recognition of Epicardial Origin.

INTRODUCTION: Reversible premature ventricular complexes-induced cardiomyopathy (PVC-CMP) is a well-described, multi-factorial entity. Single predictors, such as PVC burden or QRS duration, may not apply equally to all patients in contemporary unselected populations including patients with structural heart disease (SHD) or with particular origin such as epicardial (EPI) PVC. We sought to evaluate clinical criteria associated with PVC-CMP notably focusing on the EPI origin impact and ECG recognition and the value of a new composite predictor of PVC-CMP, the PVC-CMP-Index. METHODS AND RESULTS: We studied 107 consecutive patients (69 men; mean age = 56 ± 16 years) with frequent PVC (23.1 ± 11.5%) referred for PVC ablation. Thirty-six patients (33.6%) had an underlying SHD and 25 patients (23.4%) an EPI PVC origin. After a mean follow-up of 22.7 ± 15.3 months, 72.9% achieved a long-term successful ablation and 54.2% had PVC-CMP. PVC-CMP prevalence was significantly higher in patients with an EPI compared to endocardial PVC focus (84.0% vs. 45.1%, respectively, P < 0.001). EPI PVC origin (OR = 68.7 IC95% [3.5-1363], P = 0.005), as well as SHD (OR = 12.3 IC95% [1.6-92.6], P = 0.015), was independent predictor of PVC-CMP. While PVC burden (AUC = 0.78) or PVC-QRS width (AUC = 0.68) independently predicted PVC-CMP, the PVC-CMP-Index (values ≥39) defined as: PVC burden (0-1) × PVC-QRS width (milliseconds) × a constant C (1.28 for SHD or 2 for ECG suggesting EPI origin based on our ECG 3-step algorithm), highly correlated with PVC-CMP (AUC = 0.91, sensitivity = 93%, specificity = 80%). CONCLUSION: We developed a new index, which incorporates PVC burden, QRS width, and presence of SHD or suspected EPI origin that best predicted PVC-CMP.

First detection of tetrodotoxin in the bivalve Paphies australis by liquid chromatography coupled to triple quadrupole mass spectrometry with and without precolumn reaction.

Two methods for the determination of tetrodotoxin (TTX) in marine biota have been developed and validated using ultra-performance LC coupled to triple quadrupole MS. The direct analysis of TTX is completed in one method, while the other method detects the dehydration product of TTX after reaction with base. The methods were validated in a single-laboratory trial and used to test Paphies australis (pipi) samples collected from Whangapoua, New Zealand during April 2011. Pa. australis is a commonly eaten species of bivalve that was found to contain TTX at levels up to 0.80 mg/kg in this study. The methods exhibited recoveries ranging from 94 to 120%, and the within laboratory reproducibility ranged from 6 to 27% for Pleurobranchaea maculata (grey-side gilled sea slug) and bivalve matrixes. Use of the method using a dehydration step showed no evidence of TTX analogs in any of the samples.

Electrical cardioversion of atrial arrhythmias with cardiac amyloidosis in the era of direct oral anticogulants.

AIMS: Atrial fibrillation (AF)/atrial flutter is common during cardiac amyloidosis (CA). Electrical cardioversion (EC) is a strategy to restore sinus rhythm (SR). However, left atrial thrombus (LAT) represents a contraindication for EC. CA patients with AF/atrial flutter have a high prevalence of LAT. We aimed to evaluate EC characteristics, LAT prevalence and risk factors, and AF/atrial flutter outcome in CA patients undergoing EC, predominantly treated with direct oral anticoagulants (DOACs). METHODS AND RESULTS: All patients with CA and AF/atrial flutter referred for the first time to our national referral centre of amyloidosis for EC from June 2017 to February 2021 were included in this study. In total, 66 patients (median age 74.5 [70;80.75] years, 67% male) were included with anticoagulation consisted of DOAC in 74% of cases. All patients underwent cardiac imaging before EC to rule out LAT. EC was cancelled due to LAT in 14% of cases. Complete thrombus resolution was observed in only 17% of cases. The two independent parameters associated with LAT were creatinine [hazard ratio (HR) = 1.01; confidence interval (CI) = 1.00-1.03, P = 0.036] and the use of antiplatelet agents (HR = 13.47; CI = 1.85-98.02). EC acute success rate was 88%, and we observed no complication after EC. With 64% of patients under amiodarone, AF/atrial flutter recurrence rate following EC was 51% after a mean follow-up of 30 ± 27 months. CONCLUSIONS: Left atrial thrombus was observed in 14% of CA patients listed for EC and mainly treated with DOAC. The acute EC success rate was high with no complication. The long-term EC success rate was acceptable (49%).

Impact of cardiac resynchronization therapy optimization inside a heart failure programme: a real-world experience.

AIMS: This study sought to describe and evaluate the impact of a routine in-hospital cardiac resynchronization therapy (CRT) programme, including comprehensive heart failure (HF) evaluation and systematic echo-guided CRT optimization. METHODS AND RESULTS: CRT implanted patients were referred for optimization programme at 3 to 12 months from implantation. The program included clinical and biological status, standardized screening for potential cause of CRT non-response and systematic echo-guided atrioventricular and interventricular delays (AVd and VVd) optimization. Initial CRT-response and improvement at 6 months post-optimization were assessed with a clinical composite score (CCS). Major HF events were tracked during 1 year after optimization. A total of 227 patients were referred for CRT optimization and enrolled (71 ± 11 years old, 77% male, LVEF 30.6 ± 7.9%), of whom 111 (48.9%) were classified as initial non-responders. Left ventricular lead dislodgement was noted in 4 patients (1.8%), and loss or ≤90% biventricular capture in 22 (9.7%), mostly due to arrhythmias. Of the 196 patients (86%) who could undergo echo-guided CRT optimization, 71 (36.2%) required VVd modification and 50/144 (34.7%) AVd modification. At 6 months post-optimization, 34.3% of the initial non-responders were improved according to the CCS, but neither AVd nor VVd echo-guided modification was significantly associated with CCS-improvement. After one-year follow-up, initial non-responders maintained a higher rate of major HF events than initial responders, with no significant difference between AVd/VVd modified or not. CONCLUSIONS: Our study supports the necessity of a close, comprehensive and multidisciplinary follow-up of CRT patients, without arguing for routine use of echo-guided CRT optimization.

Describing mode of death in three major cardiac amyloidosis subtypes to improve management and survival.

BACKGROUND: The three main cardiac amyloidosis (CA) types have different progression and prognosis. Little is known about the mode of death (MOD) which is commonly attributed to cardiovascular causes in CA. Improving MOD's knowledge could allow to adapt patient care. OBJECTIVE: This retrospective study describes the MOD that occurred during long-term follow-up in CA patients in light-chain (AL), transthyretin hereditary (ATTRv) or wild-type (ATTRwt). MATERIAL AND METHODS: Patients referred to and cared for, at the French referral centre for CA, Henri Mondor Hospital, Créteil between 2010 and 2016 were included. Clinical information surrounding patient deaths were investigated and centrally evaluated by two blinded clinical committees which classified MOD as cardiovascular, non-cardiovascular or unknown and sub-classified it depending on its subtype. RESULTS: From the 566 patients included, 187 had AL, 206 ATTRv and 173 ATTRwt. During the 864 patient-year follow-up, 160 (28%) deaths occurred, with median survival time of 17.3 months (interquartile range 5.1-35.4). The most frequent MOD was cardiovascular (64%) of which worsening heart failure occurred most frequently and for which, 69% were of AL subtype, 79% ATTRv and 76% ATTRwt. Sudden death also occurred more frequently in AL subtype accounting for 29% of AL deaths. Non-cardiovascular MOD occurred in 26% of patients overall. Among these, infection was the most common non-cardiovascular MOD in any type of CA (80%). CONCLUSIONS: Mortality is high during natural course of CA and differs between subtypes. The main MOD were worsening heart failure, sudden death and infection, opening room to optimise management.

Implantation of cardiac electronic devices in active COVID-19 patients: Results from an international survey.

BACKGROUND: Cardiac implantable electronic device (CIED) implantation rates as well as the clinical and procedural characteristics and outcomes in patients with known active coronavirus disease 2019 (COVID-19) are unknown. OBJECTIVE: The purpose of this study was to gather information regarding CIED procedures during active COVID-19, performed with personal protective equipment, based on an international survey. METHODS: Fifty-three centers from 13 countries across 4 continents provided information on 166 patients with known active COVID-19 who underwent a CIED procedure. RESULTS: The CIED procedure rate in 133,655 hospitalized COVID-19 patients ranged from 0 to 16.2 per 1000 patients (P <.001). Most devices were implanted due to high-degree/complete atrioventricular block (112 [67.5%]) or sick sinus syndrome (31 [18.7%]). Of the 166 patients in the study survey, the 30-day complication rate was 13.9% and the 180-day mortality rate was 9.6%. One patient had a fatal outcome as a direct result of the procedure. Differences in patient and procedural characteristics and outcomes were found between Europe and North America. An older population (76.6 vs 66 years; P <.001) with a nonsignificant higher complication rate (16.5% vs 7.7%; P = .2) was observed in Europe vs North America, whereas higher rates of critically ill patients (33.3% vs 3.3%; P <.001) and mortality (26.9% vs 5%; P = .002) were observed in North America vs Europe. CONCLUSION: CIED procedure rates during known active COVID-19 disease varied greatly, from 0 to 16.2 per 1000 hospitalized COVID-19 patients worldwide. Patients with active COVID-19 infection who underwent CIED implantation had high complication and mortality rates. Operators should take these risks into consideration before proceeding with CIED implantation in active COVID-19 patients.

Severe Heart Failure Associated With Tachycardia-Induced Cardiomyopathy Due to Incessant Atrioventricular Re-Entrant Tachycardia.

Short RP interval atrioventricular re-entrant tachycardias do not typically present as an incessant form. We present 2 cases of incessant atrioventricular re-entrant tachycardias leading to tachycardia-induced cardiomyopathy with severe heart failure presentation in middle-aged adults. Both underwent accessory pathway ablation and recovered normal left ventricle function before hospital discharge. (Level of Difficulty: Intermediate.).

Single-catheter simplified stepwise approach to persistent atrial fibrillation ablation: A feasibility study.

BACKGROUND: The strategy for atrial fibrillation ablation in persistent atrial fibrillation remains controversial. A single-catheter approach was recently validated for pulmonary vein isolation. AIM: To evaluate the feasibility of this approach to performing persistent atrial fibrillation ablation, including pulmonary vein isolation and atrial lines, if needed. METHODS: We prospectively included 159 consecutive patients referred to our centre for a first persistent atrial fibrillation ablation between January 2018 and December 2018. All patients underwent pulmonary vein isolation. If the patient was still in atrial fibrillation (spontaneously or inducible), we subsequently performed a stepwise approach, including roof line, anterior mitral line, posterior box lesion and cavotricuspid isthmus line. Finally, if patient remained in atrial fibrillation at the end of the procedure, a synchronized direct-current cardioversion was applied to restore sinus rhythm. RESULTS: At baseline, 54 patients were in sinus rhythm and underwent pulmonary vein isolation. For patients in atrial fibrillation, after pulmonary vein isolation and ablation of additional lines, if needed, 18 patients were converted to atrial tachycardia and one directly to sinus rhythm; 96 were still in atrial fibrillation and underwent direct-current cardioversion. After a mean follow-up of 17±6 months, 57 patients (36%) experienced atrial arrhythmia recurrence. No deaths, tamponades or phrenic nerve injuries were observed following the procedure. The main mode of arrhythmia recurrence was atrial fibrillation in 75% of cases and atrial tachycardia in 25% of cases. CONCLUSION: A single-catheter approach, including pulmonary vein isolation and atrial lines, is feasible and safe in patients undergoing persistent atrial fibrillation ablation, with an acceptable success rate of 64% at mid-term follow-up.

Predictive value of premature atrial complex characteristics in pulmonary vein isolation for patients with paroxysmal atrial fibrillation.

BACKGROUND: Premature atrial complexes from pulmonary veins are the main triggers for atrial fibrillation in the early stages. Thus, pulmonary vein isolation is the cornerstone of catheter ablation for paroxysmal atrial fibrillation. However, the success rate remains perfectible. AIM: To assess whether premature atrial complex characteristics before catheter ablation can predict pulmonary vein isolation success in paroxysmal atrial fibrillation. METHODS: We investigated consecutive patients who underwent catheter ablation for paroxysmal atrial fibrillation from January 2013 to April 2017 in two French centres. Patients were included if they were treated with pulmonary vein isolation alone, and had 24-hour Holter electrocardiogram data before catheter ablation available and a follow-up of≥6 months. Catheter ablation success was defined as freedom from any sustained atrial arrhythmia recurrence after a 3-month blanking period following catheter ablation. RESULTS: One hundred and three patients were included; all had an acute successful pulmonary vein isolation procedure, and 34 (33%) had atrial arrhythmia recurrences during a mean follow-up of 30±15 months (group 1). Patients in group 1 presented a longer history of atrial fibrillation (71.9±65.8 vs. 42.9±48.4 months; P=0.008) compared with those who were "free from arrhythmia" (group 2). Importantly, the daily number of premature atrial complexes before catheter ablation was significantly lower in group 1 (498±1413 vs. 1493±3366 in group 2; P=0.028). A daily premature atrial complex cut-off number of<670 predicted recurrences after pulmonary vein isolation (41.1% vs. 13.3%; sensitivity 88.2%; specificity 37.7%; area under the curve 0.635; P=0.017), and was the only independent predictive criterion in the multivariable analysis (4-fold increased risk). CONCLUSION: Preprocedural premature atrial complex analysis on 24-hour Holter electrocardiogram in paroxysmal atrial fibrillation may improve patient selection for pulmonary vein isolation.

Dexamethasone is associated with early deaths in light chain amyloidosis patients with severe cardiac involvement.

BACKGROUND: Cardiac light chain amyloidosis (AL-CA) patients often die within three months of starting chemotherapy. Chemotherapy for non-immunoglobulin M gammopathy with AL-CA frequently includes bortezomib (Bor), cyclophosphamide (Cy), and dexamethasone (D). We previously reported that NT-ProBNP levels can double within 24h of dexamethasone administration, suggesting a deleterious impact on cardiac function. In this study, we evaluate the role of dexamethasone in early cardiovascular mortality during treatment. METHODS AND FINDINGS: We retrospectively assessed 100 de novo cardiac AL patients (62% male, mean age 68 years) treated at our institute between 2009 and 2018 following three chemotherapy regimens: CyBorDComb (all initiated on day 1; 34 patients), DCyBorSeq (D, day 1; Cy, day 8; Bor, day 15; 17 patients), and CyBorDSeq (Cy, day 1; Bor, day 8; D, day 15; 49 patients). The primary endpoint was cardiovascular mortality and cardiac transplantation at days 22 and 455. At day 22, mortality was 20.6% with CyBorDComb, 23.5% with DCyBorSeq, and 0% with CyBorDSeq (p = 0.003). At day 455, mortality was not significantly different between regimens (p = 0.195). Acute toxicity of dexamethasone was evaluated on myocardial function using a rat model of isolated perfused heart. Administration of dexamethasone induced a decrease in left ventricular myocardium contractility and relaxation (p<0.05), supporting a potential negative inotropic effect of dexamethasone in AL-CA patients with severe cardiac involvement. CONCLUSION: Delaying dexamethasone during the first chemotherapy cycle reduces the number of early deaths without extending survival. It is clear that dexamethasone is beneficial in the long-term treatment of patients with AL-CA. However, the initial introduction of dexamethasone during treatment is critical, but may be associated with early cardiac deaths in severe CA. Thus, it is important to consider the dosage and timing of dexamethasone introduction on a patient-severity basis. The impact of dexamethasone in the treatment of AL-CA needs further investigation.