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JACC. Advances Jan 2024Multilevel obstruction in left ventricular inflow and outflow predisposes to arrhythmias in Shone's complex (SC).
BACKGROUND
Multilevel obstruction in left ventricular inflow and outflow predisposes to arrhythmias in Shone's complex (SC).
OBJECTIVES
The purpose of this study was to study the prevalence and outcomes (heart failure [HF] hospitalization, cardiac transplant, death) of cardiac arrhythmias in adults with SC.
METHODS
Adults with SC (defined as ≥2 lesions out of supramitral ring, parachute mitral valve, subvalvular/valvular aortic stenosis (AS), and aortic coarctation) seen at Mayo Clinic between January 1999 and March 2020 were identified and evaluated for the presence of sustained atrial fibrillation, atrial flutter, and ventricular arrhythmias (VA). Kaplan-Meier survival analysis was used to calculate the occurrence of these arrhythmias.
RESULTS
Seventy-three patients with SC (mean age at first visit 33 ± 13 years) were identified. Most common anomalies were valvular AS (88%), coarctation (85%), parachute mitral valve (44%), subvalvular AS (44%), and supramitral ring (25%). Atrial arrhythmias were diagnosed in 24 patients (33%) at a mean age of 34.6 ± 12.7 years. Patients with atrial fibrillation and atrial flutter had higher number of surgeries, left atrial size, right ventricular systolic pressure, and HF hospitalizations. A rhythm control approach was used in majority of patients (75% on antiarrhythmic drugs and 50% underwent catheter ablation). Sustained VA occurred in 6 of 73 patients of whom 4 had an ejection fraction <40%. Death and cardiac transplantation occurred in 11 and 3 patients, respectively, during a median follow-up of 7.3 ± 6.0 years.
CONCLUSIONS
In adults with SC, atrial arrhythmias occurred in one-third of patients, were associated with more HF hospitalizations, and frequently required rhythm control. Prevalence of sustained VA was 8% and implantable cardioverter-defibrillator implantation should be considered in those with reduced ejection fraction.
PubMed: 38939811
DOI: 10.1016/j.jacadv.2023.100715 -
Annals of Noninvasive Electrocardiology... Jul 2024A 23-year-old male with a history of ventricular pre-excitation and atrial flutter presented for evaluation after recurrent syncope. The possible mechanism of syncope...
A 23-year-old male with a history of ventricular pre-excitation and atrial flutter presented for evaluation after recurrent syncope. The possible mechanism of syncope erroneously attributed to pre-excited atrial flutter with fast heart rates in the first hospitalization. The patient was found to have advanced heart block and PRKAG2 genetic mutation in the second hospitalization. The genetic findings and clinical features are consistent with PRKAG2 syndrome (PS). PS is a rare, autosomal dominant inherited disease, characterized by ventricular pre-excitation, supraventricular tachycardia, and cardiac hypertrophy. It is frequently followed by atrial-fibrillation-induced ventricular fibrillation and advanced heart blocks. An accurate differential diagnosis of syncope is important because of the different arrhythmic features and clinical course of PS.
Topics: Humans; Male; Young Adult; Electrocardiography; Accessory Atrioventricular Bundle; Diagnosis, Differential; Syncope; AMP-Activated Protein Kinases; Syndrome
PubMed: 38937983
DOI: 10.1111/anec.13134 -
Journal of Clinical Medicine Jun 2024Tachycardia-induced cardiomyopathy (TIC) is caused by prolonged tachycardia, leading to left ventricular dilatation and systolic dysfunction with heart failure.... (Review)
Review
Tachycardia-induced cardiomyopathy (TIC) is caused by prolonged tachycardia, leading to left ventricular dilatation and systolic dysfunction with heart failure. Although TIC is more common in adults, it is rare in early infancy. Clinical testing was performed as part of medical evaluation and management. Next-generation sequencing (NGS) was conducted for a patient with TIC. A literature review on TIC was also conducted. The case involved a 5-month-old infant referred to the hospital due to symptoms of heart failure lasting at least two months. The infant's heart rate was 200 beats per minute, the left ventricular ejection fraction fell below 14%, and electrocardiograms showed atrial flutter, suggesting TIC. After cardioversion, there was no recurrence of atrial flutter, and cardiac function improved 98 days after tachycardia arrest. The NGS did not identify any pathogenic variants. The literature review identified eight early infantile cases of TIC. However, no previous reports described a case with such a prolonged duration of TIC as ours. This is the first report of a case of prolonged TIC in a child with the documented time to recover normal cardiac function. The improvement of cardiac function depends on the duration of TIC. Early recognition and intervention in TIC are essential to improve outcomes for infantile patients, as timely treatment offers the potential for recovery.
PubMed: 38893024
DOI: 10.3390/jcm13113313 -
Frontiers in Cardiovascular Medicine 2024The prevalence of congenital heart disease (CHD) in adult patients has risen with advances in diagnostic and surgical techniques. Surgical modifications and hemodynamic... (Review)
Review
The prevalence of congenital heart disease (CHD) in adult patients has risen with advances in diagnostic and surgical techniques. Surgical modifications and hemodynamic changes increase the susceptibility to arrhythmias, impacting morbidity and mortality rates, with arrhythmias being the leading cause of hospitalizations and sudden deaths. Patients with CHD commonly experience both supraventricular and ventricular arrhythmias, with each CHD type associated with different arrhythmia patterns. Macroreentrant atrial tachycardias, particularly cavotricuspid isthmus-dependent flutter, are frequently reported. Ventricular arrhythmias, including monomorphic ventricular tachycardia, are prevalent, especially in patients with surgical scars. Pharmacological therapy involves antiarrhythmic and anticoagulant drugs, though data are limited with potential adverse effects. Catheter ablation is preferred, demanding meticulous procedural planning due to anatomical complexity and vascular access challenges. Combining imaging techniques with electroanatomic navigation enhances outcomes. However, risk stratification for sudden death remains challenging due to anatomical variability. This article practically reviews the most common tachyarrhythmias, treatment options, and clinical management strategies for these patients.
PubMed: 38887448
DOI: 10.3389/fcvm.2024.1395210 -
Zhonghua Xin Xue Guan Bing Za Zhi Jun 2024To evaluate the incidence of arrhythmias and electrocardiographic (ECG) characteristics in cancer patients treated with immune checkpoint inhibitors (ICIs). This was a...
To evaluate the incidence of arrhythmias and electrocardiographic (ECG) characteristics in cancer patients treated with immune checkpoint inhibitors (ICIs). This was a cohort study conducted in the Fourth Hospital of Hebei Medical University. Cancer patients initiating ICIs treatments from November 2020 to September 2022 were included in this study. Baseline 12-leads ECG before ICIs initiation and post-treatment ECG were analyzed. An abnormal ECG was defined as the presence of any of the following changes: sinus arrhythmias, atrial fibrillation, atrial flutter, paroxysmal supraventricular tachycardia, ventricular tachycardia, premature contractions, conduction disorder, and ST-T changes. A total of 87 patients were enrolled, aged 63 (57, 68) years, with 66 (75.9%) males. And 44.8% (39/87) of patients presented with at least one confirmed cardiovascular disease or cardiovascular risk factor at baseline. The incidence of abnormal ECG increased from 31.0% (27/87) at baseline to 65.5% (57/87) after receiving (5.0±2.7) cycles of ICIs treatment (<0.001). The incidence of sinus arrhythmias was significantly increased after ICIs treatment (23.0% (20/87) vs. 9.2% (8/87), =0.023), of which only the incidence of sinus tachycardia was significantly increased (11.5% (10/87) vs. 2.3% (2/87), =0.039). There was also a significantly increased incidence of ST-T changes after ICIs treatment (31.0% (27/87) vs. 17.2% (15/87), =0.012), which mainly attributed to the T wave changes (29.9% (26/87) vs. 13.8% (12/87), =0.001). The incidence of premature contractions was also significantly increased after ICIs treatment (9.2% (8/87) vs. 0, =0.008). Additionally, compared with baseline, the P wave axis was significantly increased after ICIs treatment ((56.94±21.01)° vs. (52.00±22.69)°, =0.043). After ICIs treatment, the heart rate was significantly increased ((79.07±15.37) beats/min vs. (75.64±13.37) beats/min, =0.029). Sokolow-Lyon index ((2.21±0.81)mV vs. (2.33±0.75)mV, =0.138), QTc interval ((431.44±36.04)ms vs. (428.00±30.05)ms, =0.415) all showed signs of change after treatment, but did not reach the traditional significant level. The incidence of abnormal ECG is significantly increased after ICIs treatment, especially for sinus tachycardia, premature contractions and T wave changes; the P wave axis and heart rate is also significantly increased after treatment. It is important to perform regular ECG monitoring in patients receiving ICIs treatment.
Topics: Humans; Male; Middle Aged; Female; Neoplasms; Electrocardiography; Aged; Arrhythmias, Cardiac; Immune Checkpoint Inhibitors; Cohort Studies; Incidence; Risk Factors
PubMed: 38880749
DOI: 10.3760/cma.j.cn112148-20231008-00264 -
JACC. Heart Failure May 2024Mineralocorticoid receptor antagonists (MRAs) improve outcomes in patients with heart failure and reduced ejection fraction (HFrEF). However, MRAs are often underused...
BACKGROUND
Mineralocorticoid receptor antagonists (MRAs) improve outcomes in patients with heart failure and reduced ejection fraction (HFrEF). However, MRAs are often underused because of hyperkalemia concerns.
OBJECTIVES
The purpose of this study was to assess whether sodium zirconium cyclosilicate (SZC), a nonabsorbed crystal that traps and rapidly lowers potassium, enables MRA use in patients with HFrEF and prevalent hyperkalemia (or at high risk).
METHODS
REALIZE-K is a prospective, double-blind, placebo-controlled trial in patients with HFrEF (NYHA functional class II-IV; left ventricular ejection fraction ≤40%), optimal therapy (except MRA), and prevalent hyperkalemia (or at high risk). During the open-label run-in, all participants underwent protocol-mandated spironolactone titration (target: 50 mg daily); those with prevalent (cohort 1) or incident (cohort 2) hyperkalemia during titration started SZC. Participants achieving normokalemia while on spironolactone ≥25 mg daily were randomized to continuing SZC or matching placebo for 6 months. The primary composite endpoint was proportion of participants with optimal response (normokalemia, on spironolactone ≥25 mg daily, no rescue for hyperkalemia [months 1-6]).
RESULTS
Of 365 patients (run-in), 202 were randomized. Baseline characteristics included mean age 70 years, prevalent comorbidities (78% estimated glomerular filtration rate <60 mL/min/1.73 m, 38% atrial fibrillation/flutter), high N-terminal pro B-type natriuretic peptide (median 1,136 pg/mL), and high HFrEF therapy use (64% sacubitril/valsartan, 96% beta-blocker, 42% sodium glucose co-transporter 2 inhibitor). At randomization, 78% were receiving spironolactone 50 mg daily.
CONCLUSIONS
REALIZE-K is the first trial to evaluate whether SZC can enable rapid and safe MRA optimization and long-term continuation in patients with HFrEF and prevalent/high risk of hyperkalemia. (Study to Assess Efficacy and Safety of SZC for the Management of High Potassium in Patients with Symptomatic HFrEF Receiving Spironolactone; NCT04676646).
PubMed: 38878009
DOI: 10.1016/j.jchf.2024.05.003 -
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 -
Medicine Jun 2024In recent years, significant advancements in radiofrequency ablation technology have notably enhanced arrhythmia treatment in cardiology. Technological advancements and...
In recent years, significant advancements in radiofrequency ablation technology have notably enhanced arrhythmia treatment in cardiology. Technological advancements and increasing clinical adoption have made radiofrequency ablation a key therapy in improving life quality for patients with conditions like atrial fibrillation (AF). Consequently, there has been a marked increase in research output, underscoring the technology's significance and its potential in cardiology. Aims to comprehensively analyze cardiology's radiofrequency ablation research trends, identifying leading countries and institutions in international collaborations, key researchers' contributions, and evolving research hotspots. The study, based on the Web of Science Core Collection database, reviewed the literatures from 2004 to 2023. CiteSpace 6.2.R7 Basic was used for bibliometric analysis, which examined annual publication trends, international collaboration networks, key authors, leading research institutions, major journals, keyword co-occurrence and clustering trends. Analyzing 3423 relevant articles, this study reveals a consistent growth in cardiology radiofrequency ablation research since 2004. The analysis shows that the United States, Germany, and France hold central roles in the international collaboration network, with leading authors from premier US and European institutions. Keyword cluster analysis identifies "atrial flutter" and "ventricular tachycardia" as current research focal points. Cardiology radiofrequency ablation research shows a growth trend, led by the United States and European countries. Research hotspots are concentrated on the diverse applications of radiofrequency ablation technology and the treatment of AF. Future studies may increasingly focus on technological innovation and the deepening of clinical applications.
Topics: Bibliometrics; Humans; Cardiology; Radiofrequency Ablation; Biomedical Research; Atrial Fibrillation; Catheter Ablation
PubMed: 38847657
DOI: 10.1097/MD.0000000000038498 -
European Journal of Case Reports in... 2024Inappropriate therapy is a frequent adverse consequence of implantable cardioverter-defibrillator. Inappropriate therapy often occurs due to the misinterpretation of...
UNLABELLED
Inappropriate therapy is a frequent adverse consequence of implantable cardioverter-defibrillator. Inappropriate therapy often occurs due to the misinterpretation of sinus tachycardia or atrial fibrillation/flutter with rapid atrioventricular conduction by the device. Current implantable cardioverter-defibrillator (ICD) mechanisms integrate various discriminators into algorithms to differentiate supraventricular tachycardia (SVT) from ventricular tachycardia (VT), to prevent such occurrences. A 40-year-old man suffered seizures and cardiac arrest abruptly, without prior complaints of chest pain. Without delay, he initiated cardiopulmonary resuscitation (CPR), resulting in the regaining of spontaneous circulation. The patient had previously received a single-chamber ICD due to recurring VT and a prior episode of cardiac arrest. The patient had a medical background of coronary artery disease with complete revascularisation and no previous occurrence of SVT. Interrogating the ICD revealed captured non-sustained ventricular tachycardia (NSVT) and SVT events but no VT episode or shock therapy. During the specified time period, the patient underwent an electrophysiological study, and no SVT was induced with the normal function of the atrioventricular and sinoatrial nodes. Various causes can lead to errors in morphology discrimination criteria in single-chamber ICDs. Extending the detection interval is highly recommended to avoid misclassification of ICDs.
LEARNING POINTS
This highlights the crucial significance of precise classification of supraventricular tachycardia (SVT) and ventricular tachycardia (VT) using a single-chamber implantable cardioverter-defibrillator (ICD) discriminator to guarantee prompt and appropriate therapy delivery.The morphology criterion used in single-chamber ICDs may have potential limits and inaccuracies, which might result in the misdiagnosis of VT as SVT.Further study and enhancement of differentiation algorithms, paired with precise programming and prolonged detection durations are essential to reduce such misclassifications and improve patient outcomes.
PubMed: 38846652
DOI: 10.12890/2024_004526 -
Heart Rhythm O2 May 2024Atrial fibrillation/flutter (AF) is a major public health problem and is associated with stroke, heart failure, dementia, and death. It is estimated that 20%-30% of... (Review)
Review
Atrial fibrillation/flutter (AF) is a major public health problem and is associated with stroke, heart failure, dementia, and death. It is estimated that 20%-30% of Americans will develop AF at some point in their life. Current medications to prevent AF have limited efficacy and significant adverse effects. Newer and safer therapies to prevent AF are needed. Ventricular arrhythmias are less prevalent than AF but may have significant consequences including sudden cardiac death. Metformin is the most prescribed, first-line medication for treatment of diabetes mellitus (DM). It decreases hepatic glucose production but also reduces inflammation and oxidative stress. Experimental studies have shown that metformin improves metabolic, electrical, and histologic risk factors associated with AF and ventricular arrhythmias. Furthermore, in large clinical observational studies, metformin has been associated with a reduced risk of AF in people with DM. These data suggest that metformin may have antiarrhythmic properties and may be a candidate to be repurposed as a medication to prevent cardiac arrhythmias. In this article, we review the clinical observational and experimental evidence for the association between metformin and cardiac arrhythmias. We also discuss the potential antiarrhythmic mechanisms underlying this association. Repurposing a well-tolerated, safe, and inexpensive medication to prevent cardiac arrhythmias has significant positive public health implications.
PubMed: 38840768
DOI: 10.1016/j.hroo.2024.04.003