Publications by authors named "Mikael Laredo"
Background: Inflammatory, myocarditis-like episodes precede and are associated with higher risk of sustained ventricular arrhythmias and heart failure in patients with pathogenic or likely pathogenic desmoplakin (DSP) variants. Whether the recurrence and treatment of myocarditis-like episodes influence the outcomes in this population is unknown. This study aimed to assess the prognostic impact of the recurrence and treatment of myocarditis-like episodes in patients with pathogenic or likely pathogenic DSP variants.
View Article and Find Full Text PDFArrhythmogenic cardiomyopathy (ACM) is a rare inherited disease characterized by fibrofatty replacement of the myocardium, associated with lethal arrhythmias and heart failure. ACM diagnosis is challenging, as it involves clinical, genetic, and multiparametric imaging assessments. Imaging plays a central role in evaluating ACM by targeting the intertwined morphofunctional and tissue abnormalities.
View Article and Find Full Text PDFBackground: Pulmonary vein (PV) isolation (PVI) using pulsed field ablation (PFA) is an emerging technique for the treatment of atrial fibrillation (AF). However, the recurrence rate of AF remains significant, and the durability of PVI is insufficient.
Objective: This study aimed to assess the impact of anatomical and geometrical features of the PV ostia on the PVI durability.
Background: Most data on atrial fibrillation (AF) ablation using the first available pentaspline pulsed field ablation (PFA) catheter (Farapulse, Boston Scientific Inc) come from retrospective center-level registries collected in highly experienced centers.
Objective: This study aimed to provide exhaustive and prospective patient-level data on this new ablation modality.
Methods: FRANCE-PFA is a nationwide registry (NCT06497933) that included all patients undergoing a first AF ablation using the pentaspline PFA catheter since the introduction of this technology in France.
Background: Defibrillation testing (DT) remains recommended during subcutaneous implantable cardioverter defibrillator (S-ICD) implantation due to limited supporting evidence.
Objectives: The objective of this study was to evaluate the long-term impact of DT during S-ICD implantation.
Methods: The HONEST (coHOrte fraNcaise des dEfibrillateurs Sous cuTanés) study is a nationwide, ongoing observational study, including all S-ICD recipients in France (2012-2019).
Background: Electrocardiographic findings in arrhythmogenic left ventricular cardiomyopathy (ALVC) have been limited to small studies.
Objectives: The authors aimed to analyze the electrocardiogram (ECG) characteristics of ALVC, to correlate ECG with cardiac magnetic resonance and genetic data, and to evaluate its prognostic value.
Methods: We reviewed data of 125 consecutive patients with ALVC (81.
Background: Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited cardiomyopathy associated with a high risk of ventricular arrhythmia (VA). Several animal models have been used to postulate a therapeutic role of the inhibition of the ryanodine 2 receptor via the use of flecainide for this disease. Clinical data describing its use are scarce, however, especially in patients without implantable cardioverter-defibrillators or with left ventricular (LV) involvement.
View Article and Find Full Text PDFBackground: Early (≤ 28 days) supraventricular arrhythmia (SVA) is the most common complication that occurs after patent foramen ovale (PFO) closure, but little is known about the incidence and determinants of late (> 28 days) SVA. Our aim was to evaluate the determinants of late SVA after PFO closure.
Methods: Patients with percutaneous PFO closure and risk of SVA were proposed to receive an implantable loop recorder (ILR) device from 2019 to 2023.
Pulsed-Field vs Thermal Catheter Ablation of Atrial Fibrillation in Patients With Hypertrophic Cardiomyopathy.
JACC Clin Electrophysiol
June 2025
Background: Pulsed-field ablation (PFA) may be beneficial for the treatment of atrial fibrillation (AF) in patients with hypertrophic cardiomyopathy (HCM).
Objectives: The goal of this study was to compare the safety and efficacy of PFA and thermal ablation in patients with HCM and AF.
Methods: From 2016 to 2024, patients with HCM undergoing a first AF ablation using PFA or thermal ablation (cryoballoon or radiofrequency) were retrospectively included from 3 French and Swiss centers.
Background: Arrhythmogenic cardiomyopathy (ACM) related to Desmoplakin (DSP) mutations is a distinct condition associated with particularly severe outcomes, more frequent left ventricular (LV) involvement, including fibrosis, dysfunction, and inflammatory episodes. Whether DSP-ACM is associated with specific imaging features remains elusive. This study aims to provide a comprehensive description of cardiovascular magnetic resonance (CMR) findings in patients with DSP-ACM and to compare them to RV-dominant ACM with LV involvement (LV+ right-dominant-ACM).
View Article and Find Full Text PDFA multi-modal computational fluid dynamics model of left atrial fibrillation haemodynamics validated with 4D flow MRI.
Biomech Model Mechanobiol
February 2025
Atrial fibrillation (AF) is characterized by rapid and irregular contraction of the left atrium (LA). Impacting LA haemodynamics, this increases the risk of thrombi development and stroke. Flow conditions preceding stroke in these patients are not well defined, partly due the limited resolution of 4D flow magnetic resonance imaging (MRI).
View Article and Find Full Text PDFArticle Synopsis
- The study aims to evaluate the performance and safety of subcutaneous-implantable cardioverter defibrillator (S-ICD) technology in athletes compared to nonathletes, focusing on device-related complications and shock occurrences.
- Athletes made up 10.2% of the 1493 patients studied and showed higher incidences of certain heart conditions, with a tendency to experience appropriate shocks more frequently during exercise, although this was not statistically significant after adjusting for other factors.
- Overall, S-ICDs appear to be a safe option for athletes, as there was no significant difference in overall complications or inappropriate shocks between the two groups, though athletes had a higher risk of myopotential oversensing and lead infections shortly after implant.
Article Synopsis
- Pathogenic variants in the desmoplakin (DSP) gene lead to a unique type of cardiomyopathy that doesn't fit neatly into existing categories like DCM, NDLVC, or ARVC, with limited past studies on potential predictors of severe outcomes.
- Researchers analyzed 800 patients with DSP variants from a global network over an average of 3.7 years, finding that 17.4% experienced sustained ventricular arrhythmias (VAs) and 9.0% had heart failure (HF) hospitalizations.
- Key risk factors for developing VAs included female sex, history of non-sustained and sustained VAs, and lower left ventricular ejection fraction, while T-wave inversion was linked to HF
Background: Enhanced characterization of the atrial electrical substrate may lead to better comprehension of atrial fibrillation (AF) pathophysiology.
Objective: With the use of high-density substrate mapping, we sought to investigate the occurrence of functional electrophysiological phenomena in the left atrium and to assess potential association with arrhythmia recurrences after catheter ablation.
Methods: Sixty-three consecutive patients with AF referred for ablation were enrolled.
Background: The real incidence of atrial arrhythmia (AA) after patent foramen ovale (PFO) closure and whether this complication can be prevented remain unknown. We assessed whether flecainide is effective to prevent AA during the first 3 months after PFO closure, and whether 6 months of treatment with flecainide is more effective than 3 months to prevent AA after PFO closure.
Methods: AFLOAT (Assessment of Flecainide to Lower the Patent Foramen Ovale Closure Risk of Atrial Fibrillation or Tachycardia Trial) is a prospective, multicentre, randomized, open-label, superiority trial with a blind evaluation of all the end points (PROBE [Prospective Randomized Open, Blinded End Point] design).
Clinical differences between drug-induced type 1 Brugada pattern and syndrome.
J Arrhythm
August 2024
Article Synopsis
- The study focuses on the diagnostic process of Brugada syndrome (BrS) using ajmaline to expose the Type 1 Brugada pattern in patients, highlighting limited data on different populations.
- It analyzed 260 patients (average age 43.4, mostly males) who underwent ajmaline tests, revealing a significant number with syncope history and family backgrounds of BrS or sudden cardiac death.
- Results showed that less than half of the subjects met the current diagnostic criteria for BrS, but the overall rate of serious arrhythmia events was low over a median follow-up period of three years.
Article Synopsis
- SCN5A gene variants are linked to various cardiac electrical disorders, but they can also result in complex phenotypes like overlap syndromes, which haven't been thoroughly studied.
- The study analyzed DNA from over 13,500 patients with a focus on those carrying pathogenic SCN5A variants, finding that most were tied to well-defined conditions like Brugada syndrome and long QT syndrome.
- About 19% of the variants were associated with complex phenotypes, and only a small number (8 out of 9,960 patients) showed a potential link to dilated cardiomyopathies (DCM), suggesting it's a rare association.
Article Synopsis
- Pathogenic variants in the desmoplakin (DSP) gene are linked to a specific type of arrhythmogenic cardiomyopathy, which increases the risk of serious heart rhythm issues, but current evaluation methods are unreliable for these patients.
- A study was conducted with patients from the DSP-ERADOS registry to track the occurrence of sustained ventricular arrhythmia (VA) over time, using a detailed statistical analysis to create a new clinical prediction tool.
- The research identified five key clinical factors that can help predict the risk of developing sustained VA, resulting in a new DSP risk score that demonstrated strong prediction capabilities in both the initial and external testing groups.
Article Synopsis
- Pulsed field ablation (PFA) is a new method for treating atrial fibrillation (AF) that focuses on ablating heart tissue while minimizing harm to nearby structures.
- In the MANIFEST-17K study, data from 106 centers involved 17,642 patients and showed no serious complications like esophageal damage, with only a 1% major complication rate.
- The results suggest that PFA has a strong safety profile and may change how AF is treated, compared to traditional thermal ablation methods.
Article Synopsis
- * The study finds that a history of nonsustained ventricular tachycardia is a strong predictor of future VA occurrences, although traditional risk factors such as age and male sex do not show a significant association with VA events.
- * The ARVC risk calculator, which is intended to evaluate the risk of VA, performs inadequately in this patient population, highlighting the need for a more tailored, gene-specific risk
Mode and Characteristics of Arrhythmia Initiation in Idiopathic Ventricular Fibrillation: A THESIS Substudy.
JACC Clin Electrophysiol
August 2024
Article Synopsis
- There is limited understanding of how idiopathic ventricular fibrillation (IVF) starts, but previous research suggests that it usually doesn't depend on pauses in heart rhythm.
- The study aimed to investigate the initiation patterns of polymorphic ventricular tachycardia (PVT) in IVF patients, analyzing a total of 410 arrhythmia episodes among 180 patients.
- Results showed that about 27.2% of PVT episodes were pause-dependent, with the majority occurring during normal heart rhythms and initiating PVCs mostly having short coupling intervals (under 350 ms).
Article Synopsis
- Arrhythmic mitral valve prolapse (AMVP) is a serious heart condition that can cause dangerous heart rhythms, especially in young women.
- Researchers looked at women with AMVP who had troubling heart rhythms during and after pregnancy to see if being pregnant raised their risk.
- They found that these women had more dangerous heart rhythms during pregnancy and up to 6 months after giving birth compared to when they weren't pregnant.
Article Synopsis
- The study investigates sex differences in outcomes among recipients of subcutaneous implantable cardioverter-defibrillators (S-ICDs), noting that historically, women have been underrepresented in such trials.
- Using a multicenter international registry, researchers compared 399 females to a matched cohort of males, focusing on the rate of appropriate shocks and device complications over time.
- Results showed that women had a lower rate of appropriate shocks compared to men (1.7% vs. 3.4% per year), but no significant difference in device-related complications, indicating that while women are less likely to receive effective ICD therapy, they face no increased risk of adverse effects from the devices.