Degree Atrioventricular Block Research Articles

Diagnostic and intervention value of implantable cardiac monitor in patients over 60 years of age with unexplained syncope

Objective: To investigate the value of implantable cardiac monitor (ICM) in the diagnosis and treatment of patients over 60 years old with unexplained syncope. Methods: This was a multi-center, prospective cohort study. Between June 2018 and April 2021, patients over the age of 60 with unexplained syncope at Beijing Hospital, Fuwai Hospital, Beijing Anzhen Hospital and Puren Hospital were enrolled. Patients were divided into 2 groups based on their decision to receive ICM implantation (implantation group and conventional follow-up group). The endpoint was the recurrence of syncope and cardiogenic syncope as determined by positive cardiac arrhythmia events recorded at the ICM or diagnosed during routine follow-up. Kaplan-Meier survival analysis was used to compare the differences of cumulative diagnostic rate between the 2 groups. A multivariate Cox regression analysis was performed to determine independent predictors of diagnosis of cardiogenic syncope in patients with unexplained syncope. Results: A total of 198 patients with unexplained syncope, aged (72.9±8.25) years, were followed for 558.0 (296.0,877.0) d, including 98 males (49.5%). There were 100 (50.5%) patients in the implantation group and 98 (49.5%) in the conventional follow-up group. Compared with conventional follow-up group, patients in the implantation group were older, more likely to have comorbidities, had a higher proportion of first degree atrioventricular block indicated by baseline electrocardiogram, and had a lower body mass index (all P<0.05). During the follow-up period, positive cardiac arrhythmia events were recorded in 58 (58.0%) patients in the ICM group. The diagnosis rate (42.0% (42/100) vs. 4.1% (4/98), P<0.001) and the intervention rate (37.0% (37/100) vs. 2.0% (2/98), P<0.001) of cardiogenic syncope in the implantation group were higher than those in the conventional follow-up group (all P<0.001). Kaplan-Meier survival analysis showed that the cumulative diagnostic rate of cardiogenic syncope was significantly higher in the implantation group than in the traditional follow-up group (HR=11.66, 95%CI 6.49-20.98, log-rank P<0.001). Multivariate analysis indicated that ICM implantation, previous atrial fibrillation, diabetes mellitus or first degree atrioventricular block in baseline electrocardiogram were independent predictors for cardiogenic syncope (all P<0.05). Conclusions: ICM implantation improves the diagnosis and intervention rates in patients with unexplained syncope, and increases diagnostic efficiency in patients with unexplained syncope.

A rare presentation of infective endocarditis: Phase 4 block of the left bundle branch as key for the diagnosis. A case report

Definitive diagnosis of infective endocarditis (IE) is mainly based on microbiological and imaging criteria. In a minority of cases, particularly when perivalvular area is involved, cardiac conduction disorders (CCD) may appear, which implies worse prognosis. In this scenario, different degrees of auriculoventricular block can occur, but development of bundle branch block is rare. Herein, we present a case of IE with negative initial imaging tests, where the occurrence of phase 4 bundle branch block after a sequence of type I second degree AV block was crucial to establish a definitive diagnosis and an optimal therapeutic approach.

Very early fractures of the stylet-driven Biotronik Solia lead used for left bundle branch area pacing

Abstract Introduction Left bundle branch area pacing (LBBAP) has become increasingly popular due to the relatively simple implantation procedure allowing for conduction system pacing (CSP). Initially, lumen-less leads have been used primarily for CSP. However, several authors have published encouraging results using conventional stylet-driven pacemaker (PM) leads as well and our centers have largely adopted this approach. Methods In our two tertiary referral centers, we assessed all patients, who underwent a LBBAP lead implantation using any lead. We observed several early lead fractures, exhibiting a unique failure mechanism, which we illustrate in this case-series. Results Between January 2022 and November 2023 343/393 patients (87.3%) were implanted with a Solia pacemaker lead, 46/393 (11.7%) received a SelectSecure 3830 lead, and 4/393 (1.0%) another stylet-driven lead. Three patients (0.8%) who initially were implanted with a Solia lead experienced very early intracardiac lead fractures within 1, 11 and 13 months after implantation despite good initial electrical performance values (Table shows initial values and values during the time of failure (bold)). The first case was a 54 year-old woman with permanent 3d degree AV block receiving an LBBAP lead after lead extraction. Four weeks later, she presented with presyncope and exit block at maximum output in uni- and bipolar configuration. The second case was a 72 year-old man with intermittent 3rd degree AV block in the context of an ischemic heart disease. He received a dual-chamber LBBAP PM. 13 months after the implantation, a bipolar impedance &amp;gt; 2’500Ω and exit block were noted. The third case was 65 year-old man suffering from sick sinus syndrome. He initially underwent a dual-chamber PM implantation in 2011 and due to ventricular sensing issues a transvenous lead extraction and implantation of a LBBAP lead in October 2022. During device follow-up after 11 months, a fractured LBBAP lead with bipolar impedance &amp;gt;2’500Ω and exit block during threshold testing was noticed. In all cases, X-rays and macroscopic analysis consistently showed a disintegration of the lead immediately distal to the ring electrode (Figure; site of fracture marked with an arrow). Most likely, this was caused by the repetitive shear stress at the hinge point of the lead where it is entering the septum. Conclusion No dedicated stylet-driven CSP lead is available to date. The implantation site and technique for LBBAP may exert higher mechanical stress on the distal part of the lead, making it more prone to fracture than in a conventional position. Currently, the use of conventional stylet-driven leads is still off-label and the performance of such leads should be monitored closely.TableFigure

Association between Preeclampsia and Long-term Risk of Arrhythmias.

Preeclampsia (PE), a pregnancy-induced hypertensive disorder, affects 4-5% of pregnancies worldwide. It is well known that hypertension is associated with an increased risk of arrhythmias; however, data on the association between PE and arrhythmias are sparse. In this observational cohort study, we identified all primiparous women who gave birth in Denmark (1997-2016) using Danish nationwide registries. The women were stratified on whether they developed PE during primiparous pregnancy, and followed from primiparous pregnancy to incident arrhythmia, emigration, death, or end of study (December 31, 2018). A total of 523,271 primiparous women with a median age of 28 years were included and 23,367 (4.5%) were diagnosed with PE. During a median follow-up of 10.1 years, women with vs without PE were associated with a higher incidence of arrhythmias (1.42% vs 1.02%): 1) Composite of cardiac arrest, ventricular tachycardia/fibrillation, or ICD implantation (adjusted HR 1.60 [95% CI 1.14-2.24]), 2) Composite of advanced 2nd degree or 3rd degree atrioventricular block, sinoatrial dysfunction, or pacemaker implantation (adjusted HR 1.48 [95% CI 0.97-2.23]), 3) Composite of supraventricular tachyarrhythmias or extra systoles (adjusted HR 1.34 [95% CI 1.19-1.51]), 4) Composite of all the above-mentioned arrhythmias (adjusted HR 1.37 [95% CI 1.23-1.54]). Preeclamptic women were associated with a significantly and at hitherto unknown long-term increased rate of arrhythmias. This finding suggests that women with PE may benefit from cardiovascular risk assessment, screening, and preventive education.

INITIAL EXPERIENCE IN TOTAL ENDOSCOPIC MITRAL VALVE SURGERY WITH THREE–DIMENSIONAL VIDEO–ASSISTED TECHNOLOGY

Abstract Background Minimally invasive approach is nowadays the gold standard for mitral valve disease treatment. New technological tools are the key to improve surgical results and to reduce the biological invasiveness. We report our initial experience in total endoscopic mitral valve surgery using three–dimensional video–assisted technology (EinsteinVision® 3.0, B. Braun, Aesculap AG, Tuttlingen, Germany). Methods From July 2023 to December 2023, 29 patients underwent total endoscopic mitral valve surgery with three–dimensional video–assisted technology and discharged. Results Median (Q1–Q3) age of our population was 60 years (47–67) and 65.5% were males. Median (Q1–Q3) logistic Euroscore was 2.09 (1.5–4.4) and median (Q1–Q3) EuroSCORE II was 0.84 (0.6–1.2). The majority of patients were in NYHA class II and the 48.3% presented with pulmonary hypertension (PAPs &amp;gt; 30 mmHg). Median PAPs resulted 34.5 mmHg. One patient (3.4%) suffered from mitral valve endocarditis. No conversion to full sternotomy was necessary. In six patients with left coronary dominance (20.6%) we used indocyanine green fluorescence to conduct a real–time analysis of the course of the circumflex artery during surgery. No perioperative acute myocardial infarction was observed. No 30–day mortality was reported. One patient (3.4%) suffered from renal failure requiring dialysis, respiratory failure with tracheostomy and pneumonia. Post–operative atrial fibrillation was observed in 7 patients (24.1%) and 1 patient (3.4%) required Pace–maker implantation due to third degree AV block. No re–thoracotomy for bleeding was observed and 24.1% of patients required transfusions with packed blood cells. Non stroke were detected. Median (Q1–Q3) ventilation time was 5 hours (4–7). Median (Q1–Q3) intensive care unit postoperative length of stay were 2 (2–2) days and 7 (7–8) days respectively. Conclusions In our experience, total endoscopic mitral valve surgery with three–dimensional video–assisted technology is safe and feasible with good postoperative outcomes. Moreover, the possibility to use indocyanine green fluorescence to detect the course of the circumflex artery significantly assist surgeons in localizing and avoiding it, thus reducing the risk of perioperative myocardial infarction.

AN ISOLATED ACUTE RIGHT VENTRICULAR INFARCTION

Abstract Isolated right ventricular infarction occurs only in about 3% of the overall myocardial ischemic episodes. Clinical presentation is often insidious and variable case by case. The correct diagnosis is therefore crucial for a proper management, and a good prognosis in the short and long term. A 72–year–old patient suffering from arterial hypertension went to the emergency room of our hospital for malaise and asthenia for about 12 hours that have increased in 3–4 hours before the arrival. He was sweating, tachypneic with normal value of the oxygen saturation to the finger (SpO2:96%), with arterial hypotension (pressure values = 85/50 mmHg), turgor of the jugular veins in the absence of peripheral edema. Cardiac examination revealed no pathological noises and lung examination revealed clear lung fields. Electrocardiogram showed sinus tachycardia at a rate of 118 bpm, second degree atrioventricular (AV) block 2:1 type and an AV conduction delay with a first–degree AV block (P–Q interval: 320–330 msec). A pulmonary P wave was present and the QRS complex showed predominant R waves in V2–V3 with slight repolarization abnormalities (figure, panel A). An ST–elevation in right precordial leads, V3R and V4R was evident. (figure, panel B). Echocardiographic evaluation showed a hypertrophic left ventricle with normal volume and function, with marked enlarged right sections (figure, panels C–H). Moreover, we can observe the flattening of the interventricular septum with a D shaped left ventricle. Septal flattening occurred only in diastole, expression of RV volume overload (figure, panels F–H). After taking 180 mg of ticagrelor administrated orally and 150 mg of aspirin intravenously, the patient was immediately transferred to the catheterization laboratory for emergency coronary angiography. Coronary angiography highlighting an ostial thrombotic obstruction of a co–dominant right coronary artery (RCA) in the absence of significant stenosis of the left coronary circulation (figure, panels I–M). Primary percutaneous coronary intervention of RCA was performed with STENT implantation with a good postoperative result. (figure, panels L). During the hospital stay, the patient showed a good clinical status without any CV events, with progressively normalization of electrocardiographic abnormalities and persistent sinus rhythm. He was discharged after ten days.

A CASE OF DUAL–SITE LEFT VENTRICULAR PACING PERFORMED VIA A PERSISTENT LEFT SUPERIOR VENA CAVA IN A PATIENT WITH COMPLETE ATRIO–VENTRICULAR BLOCK AND RIGHT SUPERIOR VENA CAVA OCCLUSION

Abstract Patient A 64 year old male admitted for syncope. EKG presented 3rd degree AV block. Attempting to place temporary pacemaker was unsuccessful due to occlusion of the right femoral vein and the presence of a catheter for hemodialysis in the left femoral vein. He also has complete thrombosis of the right internal jugular vein, proximal superior vena cava and right femoral vein. He was referred to ICCU for monitoring, asymptomatic with no signs of congestion or hypoperfusion. Dopamine was started at 4 mcg/kg/min and then isoprenaline 0.06 mcg/kg/min. Initial work up Echocardiography showed depressed LV ejection fraction (LVEF 40%). Chest and abdomen angio–CT showed persistence of a superior left vena cava (PSLVC), which drained in the coronary sinus (CS). Right axillary and subclavian veins were occluded, and also right superior vena cava and right jugular vein. Left jugular, axillary and subclavian veins were pervious. Left femoral and right iliac–femoral veins showed significantly narrowing of the vessel lumen. Diagnosis and Management Our indication for this patient was CRT rather than RV pacing. The implant of a leadless AV pacemaker was also considered, but it was considered unfeasible due to limited access from the femoral veins. The presence of a PSLVC cava draining into CS was confirmed with angiography in the EP Lab. At the beginning of the procedure two episodes of asystole occurred. A first bipolar lead was rapidly placed in a postero–lateral branch of the CS, to obtain a stable temporary pacing. We then placed a quadripolar, active fixation, left ventricular pacing lead via the PSLVC into an antero–lateral branch of the CS. Finally, we placed a right atrium active fixation pacing lead in the right atrium again through the PSLVC. Vascular accesses were cephalic left vein and axillary vein. Acceptable sensing and pacing parameters were achieved. The bipolar LV lead was connected to the IS–1 RV port for sensing and the quadripolar lead was connected to the IS–4 LV port for pacing. Programming was DDDR 60–130 with active LV pacing only. Total procedural time was 180 minutes. No complications occurred. At discharge electric parameters were stable. Echocardiography showed an improvement in LVEF (45% vs 40%) and ECG showed atrio–ventricular LV pacing. Conclusion As far as we know this is the first reported case of a CRT delivered by two left ventricle pacing leads both placed via a PLSVC, with no need to place a pacing lead in the right ventricle.

WHEN CLINICAL FINDINGS TAKE YOU DOWN THE WRONG PATH: PERSISTENT FEVER IN A PATIENT WITH PREVIOUS CARDIAC SURGERY

Abstract Introduction In a patient who underwent previous cardiac surgery, persistent fever may be related to endocarditis. Symptoms and cardiovascular imaging, such as echocardiogram and PET/CT, may guide clinicians and surgeons to the correct diagnosis. Discussion A 43–years–old man came to our attention because of persistent fever (lasting several months) associated with cough and asthenia. When he was 5 years old, he underwent cardiac surgery for partial atrioventricular canal defect (atrial septal defect was about 4 cm) and mitral valve cleft. 14 years ago he undertook chemotherapy due to Hodgkin‘s lymphoma. Recently a cerebral artery aneurysm, radiologically defined as mycotic but proved to be fusiform, was diagnosed and treated with neurosurgery. During a recent hospitalization, blood culture positive for Streptococcus Mitis and brachial rash were reported and antibiotic therapy was started. Suspecting endocarditis, he was referred to our department. Echocardiogram revealed anterior mitral leaflet fissure, resulting in severe mitral regurgitation. Moreover a periannular cavity of doubtful interpretation (seemingly an abscess) was described. Subsequent 18FDG–PET/CT did not detect any abnormal cardiac metabolic activity. Due to severe valve regurgitation, cardiac surgery was performed: myxomatous degenerative mitral valve leaflets, failure of mitral valve cleft closure and anomalous coronary sinus communication to the left atrium (mimicking echocardiogram findings of suspected empty abscess cavity) were observed. Thus mitral valve replacement using a biological valve prosthesis was performed. Macroscopically there was no evidence of endocarditis, confirming PET/CT scan results. During the post–surgery period, third–degree atrioventricular block episodes were noted. Therefore a bicameral pacemaker was implanted. Conclusions This case report demonstrates the importance of not stopping at the first impression, as failure of previous mitral valve repair in a patient presented with persistent fever can mimic endocarditis. Therefore, the results of diagnostic tests should be compared to patients’ medical history and their clinical presentation.

63. Reversibility of High Degree Av Block in Hypertensive and Diabetic Patient with Unstable Angina Pectoris. Should We Delay the Pacemaker?

63. Reversibility of High Degree Av Block in Hypertensive and Diabetic Patient with Unstable Angina Pectoris. Should We Delay the Pacemaker?

Abstract 1085: Vagal Nerve Schwannoma Presenting As A Syncope In A Young Patient

Introduction: Vagal schwannomas are rare, benign masses that usually develop in the cervical region but can arise anywhere along the vagus nerve. Patients may be asymptomatic; however, in most cases, patients present in their third to sixth decades, with neck swelling, hoarseness or cough. Herein, we discuss a case report of a 26-year-old male who presented after an abrupt syncopal episode with sinus bradycardia and was diagnosed with vagal schwannoma. Case Presentation: A 26-year-old male with a past medical history of bipolar disorder was brought to the hospital after an abrupt syncopal episode while driving. He denied any palpitations or prodromal symptoms prior to loss of consciousness. Inpatient cardiac monitoring revealed persistent sinus bradycardia, without high degree AV block. Treadmill EKG stress test confirmed chronotropic competence. CT head did not reveal other etiology of syncope. CT chest revealed a 2.4 x 2.0 cm left superior mediastinal mass. Cardiothoracic surgery was consulted for concern of thoracic outlet mass/mediastinal mass. Robotic-assisted left thoracoscopy was performed for mediastinal mass excision, which revealed a left vagus nerve schwannoma on frozen section. Discussion: Most vagus nerve schwannomas have been found to arise within the cervical course of the vagus nerve. Intrathoracic vagal schwannomas are rare. These tumors are usually asymptomatic, however varied symptoms such as pain, dysphagia and shortness of breath have been reported. In this case presented, the tumor possibly contributed to the heightened vagal tone and neurogenic syncope (with vasovagal syncope). It is also notable that our patient's resting heart rate normalized following excision of the mass. Of note, with a high reported incidence of peri-perioperative vocal cord paralysis, surgical excision remains a challenging mainstay of treatment in symptomatic patients. Conclusion: Vagal neoplasms should be hence considered as a differential diagnosis in patients with otherwise unexplained bradycardia with history of syncope. Reference: Neurocardiogenic syncope; Carol Chen-Scarabelli, cardiovascular nurse practitioner and Tiziano M Scarabelli, associate professor of internal medicine. BMJ 2004 Aug 7; 329 (7461):336-341.

Clinico-haematobiochemical and cardiac alterations in Trypanosoma evansi infected buffaloes of Andhra Pradesh, India.

The present research aimed to document the incidence, clinical signs, haematological, and serum biochemical alterations, as well as electrocardiography and echocardiography findings in 62 buffaloes (selected from a total of 240) infected with Trypanosoma evansi. The study spanned one year, from January 2022 to December 2022. Morphological identification of Trypanosoma evansi was done by the presence of a centrally positioned nucleus with a small sub-terminal kinetoplast at the posterior position through microscopic examination of Giemsa stained peripheral blood smears. The incidence of trypanosomosis were determined to be 26% (62/240) using stained blood smear examination and 41% (98/240) through polymerase chain reaction assay. Clinical signs exhibited by buffaloes with trypanosomosis included the lack of rumination (94%; 58/62), anorexia (90%; 56/62), emaciation (87%; 54/62), loss of milk yield (84%; 52/62), ocular discharges (82%; 51/62), depressed demeanour (81%; 50/62), sunken eye balls (61%; 38/62), fever (60%; 37/62), scleral congestion (56%; 35/62) and intermittent fever (42%; 26/62). Cardiovascular clinical findings in affected buffaloes included tachycardia (44%; 27/62), cardiac arrhythmia (24%; 15/62), cardiac murmurs (19%; 12/62) and muffled heart sounds (18%; 11/62). In the present study, buffaloes with trypanosomosis exhibited significant reduction in haemoglobin (p = 0.008), packed cell volume (p = 0.004), total erythrocyte count (p = 0.003), mean corpuscular volume (p = 0.042), total leucocyte count (p = 0.048) and absolute neutrophil count (p = 0.012); a significant increase in absolute eosinophil count (p = 0.011) and absolute monocyte count (p = 0.008) compared to the apparently healthy buffaloes. Additionally significant decrease in albumin (p = 0.001), A/G ratio (p = 0.007), calcium (p = 0.008), glucose (p = 0.007), phosphorous (p = 0.048), sodium (p = 0.008), potassium (p = 0.041) and chloride (p = 0.046) were observed in buffaloes with trypanosomosis compared to healthy ones. Buffaloes with trypanosomosis also showed significant increase in globulin (p = 0.004), aspartate aminotransferase (p = 0.008), bilirubin (p = 0.034), blood urea nitrogen (p = 0.071), creatinine (p = 0.029), cholesterol (p = 0.046), lactate dehydrogenase (p = 0.009), gamma-glutamyl transferase (p = 0.004) and creatine kinase-myoglobin binding levels (p = 0.005). Electrocardiography explorations in buffaloes with trypanosomosis revealed sinus tachycardia, low voltage QRS complex, ST segment elevation, wide QRS complex, sinus arrhythmia, sinus bradycardia, wandering pace maker, first degree atrio ventricular block, biphasic T wave and tall T wave. Echocardiography examination unveiled cardiac chamber dilatation, ventricular wall thickening and indications of pericarditis/cardiac tamponade. Necropsy was carried on the dead buffaloes during the study period disclosed severely congested blood vessels on epicardial surface, endocardial haemorrhages, and presence of pericardial fluid. Histopathological examination of the heart revealed hyaline degeneration, haemorrhages in the cardiac muscles and varying degrees of degenerative changes. Additionally, the pericardium displayed increased thickness due to presence of more elastic fibres, fibroblast cells in the myocardium, discontinuity of muscle layers, vascular congestion, perivascular mono nuclear cell infiltration and augmented thickness of the endocardium with fibroblast cell proliferation. The study's conclusion highlights cardiac alterations as secondary complications in buffaloes infected with Trypanosoma evansi. Further investigations are recommended to elucidate therapeutic modifications and refine the treatment paradigm.

Familial dilated cardiomyopathy in a child: a case report

BackgroundDilated cardiomyopathy (DCM) commonly leads to heart failure (HF) and represents the most common indication for cardiac transplantation in the pediatric population. Clinical manifestations of DCM are mainly the symptoms of heart failure; it is diagnosed by EKG, chest x-ray and echocardiography. For the idiopathic and familial diseases cases of DCM, there are no definite guidelines for treatment in children as they are treated for prognostic improvement.Case presentationWe report the case of a 2-year-old girl diagnosed with dilated cardiomyopathy associated with homozygous mutation in the Myosin Light Chain 3 gene admitted for edema in lower extremities, muscle weakness, lethargy and vomiting, and she was found to be in cardiogenic shock. Chest x-ray showed cardiomegaly and EKG showed first degree atrioventricular block. Echocardiogram showed severe biventricular systolic and diastolic dysfunction. After 70 days of hospitalization, the patient went into cardiac arrest with cessation of electrical and mechanical activity of the heart, despite cardiopulmonary resuscitative efforts.ConclusionAlthough rare, pediatric DCM carries a high risk of morbidity and mortality and a lack of curative therapy.

Antiarrhythmic Effect of SGLT-2 Inhibitors in high-degree AV Block Caused by Heart Failure: A Case Report

Highlights: 1. The antiarrhythmic effect of SGLT-2 inhibitors, particularly empagliflozin, is a very interesting topic to discuss further. 2. In patients with high degree AV block due to HF in rural areas, the use of SGLT-2 inhibitors is quite rare in Indonesia. - Background: According to WHO's Top 10 Global Health Threats, non-communicable diseases such as heart failure contribute to more than 70% of all deaths worldwide. Several studies have shown that SGLT-2 inhibitors can considerably reduce HF. As research progresses, SGLT-2 inhibitors may lessen the risk of arrhythmias in HF patients. Case Summary: A 57-year-old female with uncontrolled hypertension came to the ED after collapsing at home. The vital signs and physical examination are normal. The preliminary ECG showed a high degree AV Block with multiple multifocal PVC. Early laboratory revealed mild hypokalemia. The patient experienced a seizure the next day, and an ECG showed total AV block with a non-sustained VT episode with PVC R on T. Following critical cardiac care and stabilization, the patient underwent echocardiography, which showed mild MR and AR with a reduced ejection fraction (47.7%). Once the patient's condition has stabilized, the patient is given 1x10mg Empagliflozin PO. Discussion: SGLT-2 inhibitors are beneficial in the treatment of heart failure and arrhythmia. SGLT-2 inhibitors have antiarrhythmic effects through a variety of pathways, such as lowering preload and afterload, inhibition of sodium-hydrogen exchange in myocardial cells, and suppression of the sympathetic nervous system.

Diagnosis and treatment of arrhythmogenic cardiomyopathy in children

Objective: To summarize the clinical manifestations, experiences in diagnosis and treatment of arrhythmogenic cardiomyopathy (ACM) in children. Methods: A retrospective analysis of the clinical manifestations, laboratory tests, radiological features, treatment and follow-up results was conducted in 11 children diagnosed with ACM at the center of congenital heart disease, Beijing anzhen hospital from May 2010 to March 2022. Results: A total of 11 patients aged 2 to 16 years, including 5 males and 6 females were diagnosed with ACM. The clinical manifestations included decreased activity tolerance (7 patients), heart failure (4 patients), syncope or sudden death (3 patients), palpitation (3 patients), and chest tightness and pain (3 patients). Electrocardiogram showed right bundle branch block in 9 cases, paroxysmal ventricular tachycardia in 4 cases, frequent premature ventricular contraction in 4 cases, ventricular pre-excitation in 1 case, left bundle branch block in 1 case, and first degree atrioventricular block in 2 cases. Echocardiography showed enlargement of the right heart, widening of the right ventricular outflow tract, and thinning and bulging of the local wall of the right ventricle with reduced pulsation. Ventricular thrombosis was found in 2 cases. Six children underwent cardiac magnetic resonance imaging, which mainly showed severe enlargement of the right heart, thin free wall of the right ventricle, decreased right heart function, enhanced right ventricular myocardium, and formation of right ventricular aneurysm. Two children underwent myocardial biopsy examination and presented with typical pathological changes of ACM. Genetic tests in five patients revealed DSG2 gene mutation in 2 cases, PKP2 gene mutation in 2 cases, and MYH6 gene mutation in 1 case. All patients received anti heart failure treatment and antiarrhythmic drugs. Two children received anticoagulant treatment due to ventricular thrombosis. Radiofrequency ablation was performed in 2 patients. Glenn procedure was performed in 4 patients, and heart transplantation was performed in 1 patient due to progressive heart failure. The follow-up period ranged from 6 months to 12 years. Two cases died of right heart failure, 6 cases had different degrees of heart failure, 1 case had intermittent chest tightness and pain, and 2 cases were stable. Conclusions: ACM is a progressive genetic cardiomyopathy characterized by decreased activity tolerance, cardiac failure and arrhythmia in pediatric patients. The diagnosis is mainly based on clinical manifestations, electrocardiogram, cardiac imaging changes, and genetic testing. Early detection, diagnosis, and personalized treatment can improve the prognosis.

Conduction system disease management in patients candidate and/or treated for the aortic valve disease: an Italian Survey promoted by Italian Association of Arrhythmology and Cardiac Pacing (AIAC)

Background Conduction system disorders represent a frequent complication in patients undergoing surgical (surgical aortic valve replacement, SAVR) or percutaneous (transcatheter aortic valve implantation, TAVI) aortic valve replacement. The purpose of this survey was to evaluate experienced operators approach in this clinical condition. Methods This survey was independently conducted by the Italian Association of Arrhythmology and Cardiac Pacing (AIAC) and it consisted of 24 questions regarding the respondents’ profile, the characteristics of participating centres, and conduction disease management in different scenarios. Results Fifty-five physicians from 55 Italian arrhythmia centres took part in the survey. Prophylactic pacemaker implantation is rare. In case of persistent complete atrioventricular block (AVB), 49% and 73% respondents wait less than one week before implanting a definitive pacemaker after SAVR and TAVI, respectively. In case of second degree AVB, the respondents wait some days more for definitive implantation. Respondents consider bundle branch blocks, in particular pre-existing left bundle branch block (LBBB), the worst prognostic factors for pacemaker implantation after TAVI. The implanted valve type is considered a relevant element to evaluate. In patients with new-onset LBBB and severe/moderate left ventricular systolic dysfunction, respondents would implant a biventricular pacemaker in 100/55% of cases, respectively. Conclusions Waiting time before a definitive pacemaker implantation after aortic valve replacement has reduced compared to the past, and it is anticipated in TAVI vs. SAVR. Bundle branch blocks are considered the worse prognostic factor for pacemaker implantation after TAVI. The type of pacemaker implanted in new-onset LBBB patients without severe left ventricular systolic dysfunction is heterogeneous.

Transvenous endocardial pacing with SelectSecure™ 3830 lead in pediatric patients: case series of two infants and a literature review

BackgroundThe SelectSecure™ 3830 lead is an innovative, lumenless, and thin active fixed lead with a nonretractable screw-in tip and a diameter of 4.1 Fr, making it the thinnest pacing lead available. Its high anti-extrusion properties and durability have shown favorable outcomes in cardiac pacing, especially in pediatric patients. The superfine design and easy implantation of the lead have rendered it a preferred choice in children, particularly in cases of congenital heart disease.Case presentationThis case series presents two infant patients who underwent transvenous endocardial pacing using the SelectSecure™ 3830 lead, along with a comprehensive literature review on the topic. The study followed the patients for 5 years and 3 years, respectively, and observed stable pacing parameters, indicating a positive therapeutic outcome and safety.This article discusses the optimal age and body shape for transvenous lead implantation in infants and highlights the advantages and disadvantages of endocardial and epicardial pacing approaches. Although endocardial pacing offers several benefits such as minimal trauma, short hospital stay, and longer battery life, it may not be suitable for intracardiac shunts, and venous occlusion remains a concern. On the other hand, epicardial pacing may be considered for children with challenging endocardial access but comes with higher risk of lead failure and coronary artery compression.This study emphasizes the importance of careful follow-up in pediatric patients with pacing, as lead failure can occur in young patients owing to growth and development, leading to syncope and battery depletion. The article also underscores the significance of selecting the appropriate pacing location to minimize the impact of cardiac function, with right ventricular septal pacing emerging as a preferable option.ConclusionsThe SelectSecure™ 3830 lead presents a promising solution for transvenous endocardial pacing in pediatric patients with high degree atrioventricular block and bradycardia, ensuring safe and effective pacing as they grow and develop.

Predictors of Atrial Arrhythmia in Adults with Repaired Tetralogy of Fallot.

Tetralogy of Fallot (TOF), the most common cyanotic congenital heart disease in adults, has excellent long-term survival. However, many patients (30-45%) develop late arrhythmias. Previous studies have identified predictors of arrhythmia (atrial or ventricular) using clinical markers that predate arrhythmia onset by many years. Our objective was to develop a predictive model for incident atrial arrhythmias within two years of clinical evaluation and diagnostic testing. A single-center nested unmatched case-control study of 174 adults with repaired TOF. We included only patients with results from ECG and echocardiogram data in the required time interval (3-24 months before first arrhythmia for cases; 24 months of follow-up for controls). A predictive multivariable model for risk of incident atrial arrhythmia was developed using logistic regression with a least absolute shrinkage and selection operator (LASSO). Of 41 demographic, surgical, and diagnostic variables, six were selected as having predictive value for atrial arrhythmia based on cross validation. The factors with the greatest predictive value in decreasing order were moderate / severe tricuspid regurgitation (adjusted odds ratio (OR) 149.42), QRS fragmentation (OR 28.08), severe pulmonary regurgitation (OR 8.22), RV systolic dysfunction (OR 2.95), 1st degree AV block (OR 2.59), and age at time of surgical repair (OR 1.02). Predictors for atrial arrhythmia in our study suggested abnormal right ventricle anatomical function and electrophysiologic properties (conduction and repolarization) as the primary underlying substrate.

Safety, pharmacokinetics, and food effect of sudapyridine (WX-081), a novel anti-tuberculosis candidate in healthy Chinese subjects.

This study aimed to assess the safety, pharmacokinetics, and food impact on sudapyridine (WX-081), a novel drug designed to inhibit mycobacterium ATP synthase, with clinical applications for drug-resistant tuberculosis (TB) treatment. The research comprised two arms: a single ascending dose (SAD) arm (30 to 600 mg, N = 52) and a multiple ascending dose (MAD) arm (200 to 400 mg, N = 30). The influence of food was evaluated using a 400 mg dose within an SAD cohort. Plasma concentrations of WX-081 and M3 (main metabolite of WX-081) were analyzed using a validated liquid-chromatography tandem mass spectrometry method. In the SAD arm, mean residence time (MRT0-t), terminal half-life, and clearance of WX-081 ranged from 18.87 to 52.8 h, 31.39 to 236.57 h, and 6.4 to 80.34 L/h, respectively. The area under the curve from time zero to the last measurable timepoint (AUC0-t) of WX-081 showed dose-proportional increases in the SAD arm. The disparity between fasted and fed states of WX-081 was significant (p < 0.05), with fed dosing resulting in a 984.07% higher AUC0-t and 961.55% higher maximum plasma concentration. In both the SAD and MAD arms, one case each exhibited a 1 degree atrioventricular block. No QTc elongation was observed, and adverse events were not dose-dependent. Favorable exposure, tolerability, safety, and an extended MRT0-t suggest that WX-081 holds promise as a phase II development candidate for drug-resistant TB treatment.

Predictors of pacemaker requirement in patients with implantable loop recorder and unexplained syncope: A systematic review and meta-analysis.

Identifying the underlying cause of unexplained syncope is crucial for appropriate management of recurrent syncopal episodes. Implantable loop recorders (ILRs) have emerged as valuable diagnostic tools for monitoring patients with unexplained syncope. However, the predictors of pacemaker requirement in patients with ILR and unexplained syncope remain unclear. In this study, we shed light on these prognostic factors. PubMed/MEDLINE, EMBASE, Web of Science, and Cochrane CENTRAL were systematically searched until May 04, 2023. Studies that evaluated the predictors of pacemaker requirement in patients with implantable loop recorder and unexplained syncope were included. The "Quality In Prognosis Studies" appraisal tool was used for quality assessment. The pooled odds ratio (OR) with 95% confidence intervals (CIs) was calculated. The publication bias was evaluated using Egger's and Begg's tests. Ten studies (n = 4200) were included. Right bundle branch block (OR: 3.264; 95% CI: 1.907-5.588, p < .0001) and bifascicular block (OR: 2.969; 95% CI: 1.859-4.742, p < .0001) were the strongest predictors for pacemaker implantation. Pacemaker requirement was more than two times in patients with atrial fibrillation, sinus bradycardia and first degree AV block. Valvular heart disease, diabetes mellitus, and hypertension were also significantly more in patients with pacemaker implantation. Age (standardized mean difference [SMD]: 0.560; 95% CI: 0.410/0.710, p < .0001) and PR interval (SMD: 0.351; 95% CI: 0.150/0.553, p = .001) were significantly higher in patients with pacemaker requirement. Heart conduction disorders, atrial arrhythmias and underlying medical conditions are main predictors of pacemaker device implantation following loop recorder installation in unexplained syncopal patients.

Cardiac Sarcoidosis: A Comprehensive Clinical Review.

Sarcoidosis is an inflammatory multisystemic disease of unknown etiology characterized by the formation of non-caseating granulomas. Sarcoidosis can affect any organ, predominantly the lungs, lymphatic system, skin and eyes. While 90% of patients with sarcoidosis have lung involvement, an estimated 5% of patients with sarcoidosis have clinically manifest cardiac sarcoidosis (CS), whereas approximately 25% have asymptomatic, clinically silent cardiac involvement verified by autopsy or imaging studies. CS can present with conduction disturbances, ventricular arrhythmias, heart failure or sudden cardiac death. Approximately 30% of 60-year-old patients presenting with unexplained high degree atrioventricular (AV) block or ventricular tachycardia are diagnosed with CS, therefore CS should be strongly considered in such patients. CS is the second leading cause of death among patients affected by sarcoidosis after pulmonary sarcoidosis, therefore its early recognition is important, because early treatment may prevent death from cardiovascular involvement. The establishment of isolated CS diagnosis sometimes can be quite difficult, when extracardiac disease cannot be verified. The other reason for the difficulty to diagnose CS is that CS is a chameleon of cardiology and it can mimic (completely or almost completely) different cardiac diseases, such as arrhythmogenic cardiomyopathy, giant cell myocarditis, dilated, restrictive and hypertrophic cardiomyopathies. In this review article we will discuss the current diagnosis and management of CS and delineate the potential difficulties and pitfalls of establishing the diagnosis in atypical cases of isolated CS.