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Frontiers in Cardiovascular Medicine 2024Cardio-oncology is a new field of interest in cardiology focusing on the detection and treatment of cardiovascular diseases, such as arrhythmias, myocarditis, and heart...
Cardio-oncology is a new field of interest in cardiology focusing on the detection and treatment of cardiovascular diseases, such as arrhythmias, myocarditis, and heart failure, as side-effects of chemotherapy and radiotherapy. The association between chemotherapeutic agents and arrhythmias has previously been established. Atrial tachyarrhythmias, particularly atrial fibrillation, are most common, but ventricular arrhythmias, including those related to treatment-induced QT prolongation, and bradyarrhythmias can also occur. However, the association between chemotherapeutic agents and atrioventricular re-entrant tachycardia (AVRT)/atrioventricular node re-entrant tachycardia (AVNRT) remains poorly understood. Here, we report a patient with new-onset AVRT/AVNRT and lung cancer who underwent chemotherapy. We considered that chemotherapy or cancer itself may have been a trigger for the initiation of paroxysmal AVRT/AVNRT, and that radiofrequency catheter ablation was effective in treating this type of tachycardia. Here, possible mechanisms and potential genes (mostly ion channels) involved in AVRT/AVNRT are summarized and the mechanisms underlying the possible regulatory patterns of cancer cells and chemotherapy on ion channels are reviewed. Finally, we considered that ion channel abnormalities may link cancer or chemotherapy to the onset of AVRT/AVNRT. The aim of the present study was to highlight the association between chemotherapeutic agents and AVRT/AVNRT and to provide new insights for future research. Understanding the intermediate mechanisms between chemotherapeutic agents and AVRT/AVNRT may be beneficial in preventing chemotherapy-evoked AVRT/AVNRT (and/or other arrhythmias) in future.
PubMed: 38911514
DOI: 10.3389/fcvm.2024.1367893 -
European Heart Journal. Case Reports Jun 2024Double-wave macrore-entry is a rare mechanism of atrial tachycardia with limited documentation in the literature. We present a three-dimensional documentation of a...
BACKGROUND
Double-wave macrore-entry is a rare mechanism of atrial tachycardia with limited documentation in the literature. We present a three-dimensional documentation of a double-wave 'typical' atrial flutter in a patient with extensive atrial cardiomyopathy.
CASE SUMMARY
A 78-year-old female with a history of atrial cardiomyopathy and dual-chamber pacemaker for sinus node disease presented with palpitations and incessant atrial flutter. Electrophysiological study revealed a regular tachycardia with a cycle length (TCL) of 230 ms, with proximal to distal coronary sinus (CS) activation. Three-dimensional mapping identified two independent wavefronts circulating the cavotricuspid isthmus (CTI), each with a TCL of 460 ms. Cavotricuspid isthmus ablation resulted in conversion into a distinct tachycardia with left atrial roof origin. Linear ablation in this location slowed the TCL to 435 ms with concentric CS activation and another CTI dependent atrial flutter was mapped, this time with only one wavefront of activation. Further ablation with a second, more lateral, line in the CTI led to tachycardia interruption. Given the extensive atrial scarring and high arrhythmic recurrence risk, atrioventricular node ablation was performed.
DISCUSSION
Double-wave re-entrant tachycardias were primarily observed in experimental models, precipitating acceleration of ventricular and supraventricular tachycardias via extrastimulation. In our case, there is documentation of a spontaneous double-wave of activation around the CTI, representing the first documented double-wave 'typical' atrial flutter. Unlike other cases in the literature, the two wavefronts were equidistant, which resulted in a regular tachycardia with TCL that was half of the single-wave cycle length. Three-dimensional propagation mapping was essential to visualize the two distinct wavefronts.
PubMed: 38863991
DOI: 10.1093/ehjcr/ytae272 -
Journal of Medical Case Reports Jun 2024Bradycardia, renal failure, atrioventricular (AV) node blocking, shock, and hyperkalemia syndrome is a potentially life-threatening clinical condition characterized by...
BACKGROUND
Bradycardia, renal failure, atrioventricular (AV) node blocking, shock, and hyperkalemia syndrome is a potentially life-threatening clinical condition characterized by bradycardia, renal failure, atrioventricular (AV) node blocking, shock, and hyperkalemia. It constitutes a vicious circle in which the accumulation of pharmacologically active compounds and hyperkalemia lead to hemodynamic instability and heart failure.
CASE PRESENTATION
A 66-year-old Caucasian female patient was admitted to the emergency department presenting with fatigue and bradycardia. Upon examination, the patient was found to be anuric and hypotensive. Laboratory investigations revealed metabolic acidosis and hyperkalemia. Clinical evaluation suggested signs of digoxin toxicity, with serum digoxin concentrations persistently elevated over several days. Despite the implementation of antikalemic measures, the patient's condition remained refractory, necessitating renal dialysis and administration of digoxin immune fab.
CONCLUSION
Bradycardia, renal failure, atrioventricular (AV) node blocking, shock, and hyperkalemia syndrome is a life-threatening condition that requires prompt management. It is important to also consider potential coexisting clinical manifestations indicative of intoxication from other pharmacological agents. Specifically, symptoms associated with the accumulation of drugs eliminated via the kidneys, such as digoxin. These manifestations may warrant targeted therapeutic measures.
Topics: Humans; Female; Aged; Digoxin; Hyperkalemia; Bradycardia; Renal Dialysis; Renal Insufficiency; Anti-Arrhythmia Agents; Syndrome; Acidosis; Shock; Atrioventricular Block; Immunoglobulin Fab Fragments
PubMed: 38851740
DOI: 10.1186/s13256-024-04600-5 -
Indian Pacing and Electrophysiology... Jun 2024Despite lack of concrete evidence, right ventricular thrombus is generally considered to be a contraindication for intracardiac lead placement. We present a case of...
Despite lack of concrete evidence, right ventricular thrombus is generally considered to be a contraindication for intracardiac lead placement. We present a case of successful placement of a right ventricular defibrillator lead and left bundle branch pacing lead and atrioventricular node ablation in a patient with chronic right ventricle thrombus.
PubMed: 38839033
DOI: 10.1016/j.ipej.2024.06.001 -
ArXiv May 2024Biological systems, particularly the brain, are frequently analyzed as networks, conveying mechanistic insights into their function and pathophysiology. This is the...
Biological systems, particularly the brain, are frequently analyzed as networks, conveying mechanistic insights into their function and pathophysiology. This is the first study of a functional network of cardiac tissue. We use calcium imaging to obtain two functional networks in a subsidiary but essential pacemaker of the heart, the atrioventricular node (AVN). The AVN is a small cellular structure with dual functions: a) to delay the pacemaker signal passing from the sinoatrial node (SAN) to the ventricles, and b) to serve as a back-up pacemaker should the primary SAN pacemaker fail. Failure of the AVN can lead to syncope and death. We found that the shortest path lengths and clustering coefficients of the AVN are remarkably similar to those of the brain. The network is ``small-world," thus optimized for energy use vs transmission efficiency. We further study the network properties of AVN tissue with knock-out of the sodium-calcium exchange transporter. In this case, the average shortest path-lengths remained nearly unchanged showing network resilience, while the clustering coefficient was somewhat reduced, similar to schizophrenia in brain networks. When we removed the global action potential using principal component analysis (PCA) in wild-type model, the network lost its ``small-world" characteristics with less information-passing efficiency due to longer shortest path lengths but more robust signal propagation resulting from higher clustering. These two wild-type networks (with and without global action potential) may correspond to fast and slow conduction pathways. Laslty, a one-parameter non-linear preferential attachment model is a good fit to all three AVN networks.
PubMed: 38827454
DOI: No ID Found -
Journal of Cardiology Cases Jun 2024Patients with congenitally corrected transposition of the great arteries (ccTGA) often develop complete atrioventricular block and heart failure due to the abnormal...
UNLABELLED
Patients with congenitally corrected transposition of the great arteries (ccTGA) often develop complete atrioventricular block and heart failure due to the abnormal disposition of atrioventricular node and disadvantage of systemic right ventricle. These issues are managed with a pacing system and a ventricular assist device (VAD), respectively. While technological advances offer new treatment strategies, the simultaneous deployment of a leadless pacemaker and a VAD in cases of ccTGA remains unexplored. Here, we present a case of leadless pacemaker implantation for a VAD-supported ccTGA patient. The safety of a leadless pacemaker for a subpulmonary left ventricle and electromagnetic interference between devices are major concerns when implanting a leadless pacemaker; however, the current case overcomes these obstacles. There were no perioperative complications, and both devices were functioning without problems during a one-year follow up. We expect that, even in patients with cardiac complexity such as systemic right ventricle under VAD support, a leadless pacemaker could become the treatment of choice if the indication is appropriate, although careful and close follow up is needed.
LEARNING OBJECTIVE
Technological advances expand treatment strategies and provide significant benefits to patients with adult congenital heart disease (ACHD). However, discussion of the combination of a leadless pacemaker and a ventricular assist device (VAD) is rare. We demonstrated the efficacy of a leadless pacemaker for a subpulmonary left ventricle in a patient with systemic right ventricle on VAD. This approach could be an option even for ACHD patients.
PubMed: 38826767
DOI: 10.1016/j.jccase.2024.02.004 -
Frontiers in Physiology 2024Information about autonomic nervous system (ANS) activity may offer insights about atrial fibrillation (AF) progression and support personalized AF treatment but is not...
Information about autonomic nervous system (ANS) activity may offer insights about atrial fibrillation (AF) progression and support personalized AF treatment but is not easily accessible from the ECG. In this study, we propose a new approach for ECG-based assessment of respiratory modulation in atrioventricular (AV) nodal refractory period and conduction delay. A 1-dimensional convolutional neural network (1D-CNN) was trained to estimate respiratory modulation of AV nodal conduction properties from 1-minute segments of RR series, respiration signals, and atrial fibrillatory rates (AFR) using synthetic data that replicates clinical ECG-derived data. The synthetic data were generated using a network model of the AV node and 4 million unique model parameter sets. The 1D-CNN was then used to analyze respiratory modulation in clinical deep breathing test data of 28 patients in AF, where an ECG-derived respiration signal was extracted using a novel approach based on periodic component analysis. We demonstrated using synthetic data that the 1D-CNN can estimate the respiratory modulation from RR series alone with a Pearson sample correlation of = 0.805 and that the addition of either respiration signal ( = 0.830), AFR ( = 0.837), or both ( = 0.855) improves the estimation. Initial results from analysis of ECG data suggest that our proposed estimate of respiration-induced autonomic modulation, , is reproducible and sufficiently sensitive to monitor changes and detect individual differences. However, further studies are needed to verify the reproducibility, sensitivity, and clinical significance of .
PubMed: 38779321
DOI: 10.3389/fphys.2024.1281343 -
American Journal of Cardiovascular... 2024Permanent pacemaker implantation is increasing exponentially to treat atrio-ventricular block and symptomatic bradyarrhythmia. Despite being a minor surgery, immediate...
BACKGROUND
Permanent pacemaker implantation is increasing exponentially to treat atrio-ventricular block and symptomatic bradyarrhythmia. Despite being a minor surgery, immediate complications such as pocket infection, pocket hematoma, pneumothorax, hemopericardium, and lead displacement do occur.
METHODS
The Nationwide Inpatient Sample was queried from 2016 to 2018 to identify patients with pacemakers using ICD-10 procedure code. The Chi-square test was used for statistical analysis.
RESULTS
The sample size consisted of 443,460 patients with a pacemaker, 26% were <70 years (male 57%, mean age of (60.6±9.7) yr, Caucasian 70%) and 74% were ≥70 years (male 50%, mean age of (81.4±5.9) yr, Caucasian 79%). Upon comparison of rates in the young vs elderly: mortality (1.6% vs 1.5%; P<0.01), obesity (26% vs 13%; P<0.001), coronary artery disease (40% vs 49%; P<0.001), HTN (74% vs 87%; P<0.01), anemia (4% vs 5%; P<0.01), atrial fibrillation (34% vs 49%; P<0.01), peripheral artery disease (1.7% vs 3%; P<0.01), CHF (31% vs 39%; P<0.001), diabetes (31% vs 27.4%; P<0.01), vascular complications (1.1% vs 1.2%; P<0.01), pocket hematoma (0.5% vs 0.8%; P<0.01), AKI (16% vs 21%; P<0.01), hemopericardium (0.1% vs 0.1%; P = 0.1), hemothorax (0.3% vs 0.2%; P<0.01), cardiac tamponade (0.4% vs 0.5%; P<0.01), pericardiocentesis (0.4% vs 0.4%; P<0.01), cardiogenic shock (4% vs 2.3%; P<0.01), respiratory complications (1.9% vs 0.9%; P<0.01), mechanical ventilation (5.1% vs 2.9%; P<0.01); post-op bleed (0.5% vs 0.3%; P<0.01), need for transfusion (4.8% vs 3.8%; P<0.01), severe sepsis (0.6% vs 0.5%; P<0.01 ), septic shock (2% vs 1%; P<0.01), bacteraemia (0.8% vs 0.4%; P<0.01), lead dislodgement (1.4% vs 1.1%; P<0.01).
CONCLUSIONS
Our study revealed that the overall complication rates were lower in the elderly despite higher co-morbidities. This aligns with previous studies which showed lower rates in the elderly. Hence providers should not hesitate to provide guideline driven pacemaker placement in the elderly especially in patients with good life expectancy.
PubMed: 38764544
DOI: 10.62347/FIRV6475 -
Cardio-oncology (London, England) May 2024Cardiac tamponade as the presenting manifestation of systemic lymphoma is relatively uncommon. Pericardium is the commonest site of involvement in secondary malignancies...
BACKGROUND
Cardiac tamponade as the presenting manifestation of systemic lymphoma is relatively uncommon. Pericardium is the commonest site of involvement in secondary malignancies with systemic lymphoma involving the heart in 20% of the cases.
CASE PRESENTATION
We describe a case of a 78-year-old gentleman, who presented with symptoms of new onset cardiac failure, and hemodynamic compromise. An echocardiography revealed cardiac tamponade, necessitating an emergency pericardiocentesis. With the aid of multimodality imaging, he was found to have a right atrioventricular groove mass, widespread lymph node enlargement with bone and peritoneal involvement. Ultimately, a histopathological evaluation revealed a diagnosis of Diffuse Large B Cell Lymphoma (DLBCL).
CONCLUSIONS
Our case illustrates that a patient with DLBCL may present with cardiac tamponade as a result of metastasis. This diagnosis, although rare, is likely to be missed, which can cause fatal complications, such as cardiac tamponade, fatal arrhythmias or sudden cardiac death.
PubMed: 38762476
DOI: 10.1186/s40959-024-00202-8 -
Transplantation Proceedings May 2024Bradyarrhythmias, requiring pacemaker (PM) implantation, are common complications following orthotopic heart transplantation (HTx). Currently used heart transplantation...
BACKGROUND
Bradyarrhythmias, requiring pacemaker (PM) implantation, are common complications following orthotopic heart transplantation (HTx). Currently used heart transplantation methods are primarily the bicaval technique and the total heart transplantation technique. The aim of the study was to assess the incidence and risk factors, including donor parameters, of conduction disorders requiring pacing after HTx.
METHODS
A population of 111 (52 ± 13 years, 91 (82%) men) heart recipients was divided into a group requiring PM implantation post-HTx and a group not requiring PM. We compared groups in terms of donor parameters, time of graft ischemia, transport and transplantation, and surgical techniques as the potential risk factors for significant bradyarrhythmias.
RESULTS
Ten of 111 patients with HTx (9%) required PM implantation. The indication in 7 cases was sinus node dysfunction (SND), in 3 patients it was complete atrioventricular block (AV-block). In the PM group, the age of 48 ± 6 vs 40 ± 11 years (P = .0227) and the body mass index (BMI) 28 ± 3 vs 26 ± 4 kg/m (P = .0297) of the donor were significantly higher. There was no influence of organ transport time, ischemia time, and transplantation time. All patients requiring PM implantation were transplanted using the bicaval anastomosis: 10 (100%) vs 71 (70%) in the group not requiring PM (P = .044).
CONCLUSIONS
The need for PM implantation post-HTx despite using new techniques is still common, especially in the group operated with the bicaval method. In addition, higher donor's age and BMI are risk factors of PM implantation, what is of importance as qualification criteria of donor hearts have been gradually extended.
Topics: Humans; Heart Transplantation; Male; Risk Factors; Female; Middle Aged; Adult; Pacemaker, Artificial; Incidence; Bradycardia; Retrospective Studies; Tissue Donors
PubMed: 38697907
DOI: 10.1016/j.transproceed.2024.03.020