Mitral valve prolapse: arrhythmic risk during pregnancy and postpartum.

BACKGROUND AND AIMS: Arrhythmic mitral valve prolapse (AMVP) is linked to life-threatening ventricular arrhythmias (VAs), and young women are considered at high risk. Cases of AMVP in women with malignant VA during pregnancy have emerged, but the arrhythmic risk during pregnancy is unknown. The authors aimed to describe features of women with high-risk AMVP who developed malignant VA during the perinatal period and to assess if pregnancy and the postpartum period were associated with a higher risk of malignant VA. METHODS: This retrospective international multi-centre case series included high-risk women with AMVP who experienced malignant VA and at least one pregnancy. Malignant VA included ventricular fibrillation, sustained ventricular tachycardia, or appropriate shock from an implantable cardioverter defibrillator. The authors compared the incidence of malignant VA in non-pregnant periods and perinatal period; the latter defined as occurring during pregnancy and within 6 months after delivery. RESULTS: The authors included 18 women with AMVP from 11 centres. During 7.5 (interquartile range 5.8-16.6) years of follow-up, 37 malignant VAs occurred, of which 18 were pregnancy related occurring in 13 (72%) unique patients. Pregnancy and 6 months after delivery showed increased incidence rate of malignant VA compared to the non-pregnancy period (univariate incidence rate ratio 2.66, 95% confidence interval 1.23-5.76). CONCLUSIONS: The perinatal period could impose increased risk of malignant VA in women with high-risk AMVP. The data may provide general guidance for pre-conception counselling and for nuanced shared decision-making between patients and clinicians.

Anti-Ro and anti-La seropositivity is associated with increased rates of ischemic heart disease in adults: Results from a large population-based study.

BACKGROUND AND AIMS: Emerging evidence suggests an arrhythmogenic effect of Anti-Ro/SSA (anti-Ro) and anti-La/SSB (anti-La) antibodies in adults, potentially involving a subclinical intracardiac inflammatory process. Despite the established association between inflammation and ischemic heart disease (IHD), it is noteworthy that as of now no study has delved into the potential link between these antibodies and IHD. This population-based study aimed to examine the association between anti-Ro/La seropositivity and IHD in the general adult population. METHODS: We conducted a retrospective study using electronic medical records from the largest health maintenance organization in Israel. Patients with positive serology for either or both anti-Ro and anti-La antibodies were included, along with matched controls. Multivariate logistic regression models were utilized to assess the odds of IHD in seropositive patients compared to controls. RESULTS: Among 17,231 seropositive patients and 84,368 controls, the rate of IHD was significantly higher in the seropositive group (9.7 % vs. 8.1 %,OR = 1.23; 95%CI 1.14-1.31; p<0.001). The association was more pronounced in younger patients [<40 years old (OR = 3.36; 95%CI 1.66-6.82; p<0.001), 40-49 years old (OR = 1.85; 95%CI 1.26-2.73; p<0.01), 50-59 years old (OR = 1.87; 95%CI 1.55-2.26; p<0.001), 60-69 years old (OR = 1.26; 95%CI 1.11-1.42; p<0.001), ≥70 years old (OR = 1.11; 95%CI 1.03-1.20; p<0.01)], as well as in patients with fewer traditional cardiovascular risk-factors (none:OR = 1.29; 95 % CI 1.09 to 1.77; p<0.01, 1-2:OR = 1.30; 95 % CI 1.19 to 1.41; p<0.001, ≥3:OR = 1.09; 95 % CI 0.99 to 1.21; p=0.076). CONCLUSIONS: Our study demonstrates for the first time a positive association between anti-Ro/La seropositivity and IHD in the general adult population, especially among younger individuals with fewer traditional cardiovascular risk factors.

Utilizing Human-Induced Pluripotent Stem Cells to Study Cardiac Electroporation Pulsed-Field Ablation.

BACKGROUND: Electroporation is a promising nonthermal ablation method for cardiac arrhythmia treatment. Although initial clinical studies found electroporation pulsed-field ablation (PFA) both safe and efficacious, there are significant knowledge gaps concerning the mechanistic nature and electrophysiological consequences of cardiomyocyte electroporation, contributed by the paucity of suitable human in vitro models. Here, we aimed to establish and characterize a functional in vitro model based on human-induced pluripotent stem cells (hiPSCs)-derived cardiac tissue, and to study the fundamentals of cardiac PFA. METHODS: hiPSC-derived cardiomyocytes were seeded as circular cell sheets and subjected to different PFA protocols. Detailed optical mapping, cellular, and molecular characterizations were performed to study PFA mechanisms and electrophysiological outcomes. RESULTS: PFA generated electrically silenced lesions within the hiPSC-derived cardiac circular cell sheets, resulting in areas of conduction block. Both reversible and irreversible electroporation components were identified. Significant electroporation reversibility was documented within 5 to 15-minutes post-PFA. Irreversibly electroporated regions persisted at 24-hours post-PFA. Per single pulse, high-frequency PFA was less efficacious than standard (monophasic) PFA, whereas increasing pulse-number augmented lesion size and diminished reversible electroporation. PFA augmentation could also be achieved by increasing extracellular Ca2+ levels. Flow-cytometry experiments revealed that regulated cell death played an important role following PFA. Assessing for PFA antiarrhythmic properties, sustainable lines of conduction block could be generated using PFA, which could either terminate or isolate arrhythmic activity in the hiPSC-derived cardiac circular cell sheets. CONCLUSIONS: Cardiac electroporation may be studied using hiPSC-derived cardiac tissue, providing novel insights into PFA temporal and electrophysiological characteristics, facilitating electroporation protocol optimization, screening for potential PFA-sensitizers, and investigating the mechanistic nature of PFA antiarrhythmic properties.

Prevalence of Cardiac Sarcoidosis in Middle-Aged Adults Diagnosed with High-Grade Atrioventricular Block.

INTRODUCTION: Atrioventricular block may be idiopathic or a secondary manifestation of an underlying systemic disease. Cardiac sarcoidosis is a significant underlying cause of high-grade atrioventricular block, posing diagnostic challenges and significant clinical implications. This study aimed to assess the prevalence and clinical characteristics of cardiac sarcoidosis among younger patients presenting with unexplained high-grade atrioventricular block. METHODS: We evaluated patients aged between 18 and 65 years presenting with unexplained high-grade atrioventricular block, who were systematically referred for cardiac magnetic resonance imaging, positron emission tomography-computed tomography, or both, prior to pacemaker implantation. Subjects with suspected cardiac sarcoidosis based on imaging findings were further referred for tissue biopsy. Cardiac sarcoidosis diagnosis was confirmed based on biopsy results. RESULTS: Overall, 30 patients with high-grade atrioventricular block were included in the analysis. The median age was 56.5 years (interquartile range 53-61.75, years). In 37%, cardiac magnetic resonance imaging, positron emission tomography-computed tomography, or both, were suggestive of cardiac sarcoidosis, and in 33% cardiac sarcoidosis was confirmed by tissue biopsy. Compared with idiopathic high-grade atrioventricular block patients, all cardiac sarcoidosis patients were males (100% vs 60%, P = .029), were more likely to present with heart failure symptoms (50% vs 10%, P = .047), had thicker inter-ventricular septum on echocardiography (12.2 ± 2.7 mm vs 9.45 ± 1.6 mm, P = .002), and were more likely to present with right ventricular dysfunction (33% vs 10%, P = .047). CONCLUSIONS: Cardiac sarcoidosis was confirmed in one-third of patients ≤ 65 years, who presented with unexplained high-grade atrioventricular block. Cardiac sarcoidosis should be highly suspected in such patients, particularly in males who present with heart failure symptoms or exhibit thicker inter-ventricular septum and right ventricular dysfunction on echocardiography.

Clinical differences between drug-induced type 1 Brugada pattern and syndrome.

Background: Diagnosis of Brugada syndrome (BrS) may be established by exposing a Type 1 Brugada pattern using a sodium channel blocker. Data on the outcomes of different patient populations with drug-induced Type 1 Brugada pattern are limited. The present study reports on the characteristics and outcome of subjects with ajmaline induced Type 1 Brugada pattern. Methods: A multicenter retrospective study including all consecutive cases of ajmaline-induced Type 1 Brugada pattern from seven centers. Results: A total of 260 patients (69.9% males, mean age 43.4 ± 13.5) were included. Additional characteristics included history of syncope (n = 56, 21.5%), family history of BrS (n = 58, 22.3%) or sudden cardiac death (n = 47, 18.1%) and ventricular fibrillation (n = 3, 1.2%). Patients were divided into those meeting current diagnostic criteria for drug-induced BrS (DIBrS) and compared to the drug-induced Brugada pattern (DIBrECG). Females were significantly overrepresented in the DIBrS group (n = 50, 40% vs. n = 29, 21.5%, p = .001). A significantly higher prevalence of type 2/3 Brugada ECG at baseline was found in the DIBrECG group (n = 108, 80.8% vs. n = 75, 60% in the DIBrS, p = .026). During a median follow up of three (IQR 1.50-5.32) years, a single event of significant arrhythmia occurred in the DIBrS group. Conclusion: Less than half of subjects with ajmaline-induced Brugada pattern met current criteria for BrS. These individuals had very low rate of adverse outcomes during a follow up of 3 years, irrespective of the indication for the test or eligibility for the BrS diagnosis.

The impact of peri-procedural imaging on safety and efficacy of atrial fibrillation ablation: insights from the Israeli AF Catheter Ablation Registry (ICAR).

BACKGROUND: Pulmonary vein isolation (PVI) is the most effective therapy to achieve rhythm control in atrial fibrillation (AF). Peri-procedural imaging is used in many but not all centers. However, the impact of imaging on safety and efficacy of PVI is not clear. The Israeli Catheter Ablation Registry (ICAR) is a great opportunity to explore this issue in real-world practice. AIM: To describe the real-world utilization of peri-procedural imaging technologies in a large cohort of patients undergoing ablation for AF. METHODS: A prospective-multicenter cohort of AF patients who underwent PVI during the years 2019-2021. Peri-procedural imaging (CT, ICE, TEE) was utilized based on the center and operator discretion. The study endpoints were peri-procedural complications and AF recurrence at 12 months follow-up among patients with and without peri-procedural imaging. RESULTS: Between January 2019 and December 2021, a total of 921 patients underwent PVI. Peri-procedural imaging (at least 1 modality of CT, TEE, and or ICE) was utilized in 753 (81.8%) and no imaging among 168 (18.2%) patients. Cryoablation was the dominant energy used for PVI in both groups (92.3% of the non-imaging group, and 95.3% among imaging group), while RF was used in the rest of the patients. Fluoroscopy time was not different between the 2 groups; however, procedure duration was longer among the imaging group (90 min) compared to the non-imaging group (74.5 min, p = 0.006). By 12 months, the incidence of AF recurrence and repeated ablation were not different between the groups. Complications and re-hospitalization for cardiocerebrovascular reasons were not different among the 2 groups. Cox regression model demonstrated no association between preprocedural imaging and the risk of AF recurrence after ablation. CONCLUSION: This real-world multicenter prospective registry study demonstrated that the rate of complications and the rate of recurrence of AF during 1 year follow-up were not different among patients who had PVI either with or without peri-procedural imaging.