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European Heart Journal. Case Reports Jun 2024Acute myocarditis (AM) is an inflammatory heart disease that may occur as a consequence of autoimmune disorders. Although the correlation between myocarditis and...
Acute lymphocytic myocarditis characterized by cardiogenic shock and conduction system abnormalities in patients with Hashimoto's thyroiditis: a case report and review of literature.
BACKGROUND
Acute myocarditis (AM) is an inflammatory heart disease that may occur as a consequence of autoimmune disorders. Although the correlation between myocarditis and hyperthyroidism has been reported in the literature, the association with hypothyroidism is less frequent.
CASE SUMMARY
We describe a characteristic case of lymphocytic acute myocarditis deteriorated into cardiogenic shock due to Hashimoto's thyroiditis treated with vasopressor and inotropic drugs in combination with corticosteroid. On admission, electrocardiography revealed a sinus tachycardia with 1st degree atrioventricular (AV) block, right bundle branch block (RBBB), and left anterior fascicular block. Laboratory tests demonstrated a severe hypothyroidism and high-titre serum of antibodies against thyroglobulin. She presented a favourable clinical course, restoring haemodynamic stability. A resolution of hypothyroidism and a progressive reduction of the value of antibodies against thyroglobulin occurred. On Day 35, the patient was discharged showing on electrocardiogram the occurrence of left posterior fascicular block, disappearance of 1st degree AV block and partial improvement of RBBB along with the normalization of the left ventricular contractility abnormalities on echocardiography.
DISCUSSION
Autoimmune features, mostly Hashimoto's thyroiditis, are associated in lymphocytic acute myocarditis to a worse prognosis and an increased risk of recurrence. More studies are needed to elucidate the underlying mechanism.
PubMed: 38868158
DOI: 10.1093/ehjcr/ytae268 -
JA Clinical Reports Jun 2024Although several complications of transcranial motor-evoked potentials (Tc-MEPs) have been reported, reports of arrhythmias during Tc-MEP are very rare.
BACKGROUND
Although several complications of transcranial motor-evoked potentials (Tc-MEPs) have been reported, reports of arrhythmias during Tc-MEP are very rare.
CASE PRESENTATION
A 71-year-old woman underwent transforaminal lumbar interbody fusion under general anesthesia, with intraoperative Tc-MEP monitoring. Preoperative electrocardiography showed an incomplete right bundle branch block but no cardiovascular events in her life. After induction of anesthesia, Tc-MEP was recorded prior to the surgery. During the Tc-MEP monitoring, electrocardiography and arterial blood pressure showed a second-degree atrioventricular block, but it improved rapidly at the end of the stimulation, and the patient was hemodynamically stable. Tc-MEP was recorded seven times during surgery; the incidence of P waves without QRS complexes was significantly higher than before stimulation. The surgery was uneventful, and she was discharged eight days postoperatively without complications.
CONCLUSIONS
Our case suggests that electrical stimulation for Tc-MEP can cause arrhythmia. Electrocardiography and blood pressure must be closely monitored during Tc-MEP monitoring.
PubMed: 38862743
DOI: 10.1186/s40981-024-00722-3 -
Korean Circulation Journal May 2024His bundle pacing (HBP) and left bundle branch pacing (LBBP) are novel methods of pacing directly pacing the cardiac conduction system. HBP while developed more than two... (Review)
Review
His bundle pacing (HBP) and left bundle branch pacing (LBBP) are novel methods of pacing directly pacing the cardiac conduction system. HBP while developed more than two decades ago, only recently moved into the clinical mainstream. In contrast to conventional cardiac pacing, conduction system pacing including HBP and LBBP utilizes the native electrical system of the heart to rapidly disseminate the electrical impulse and generate a more synchronous ventricular contraction. Widespread adoption of conduction system pacing has resulted in a wealth of observational data, registries, and some early randomized controlled clinical trials. While much remains to be learned about conduction system pacing and its role in electrophysiology, data available thus far is very promising. In this review of conduction system pacing, the authors review the emergence of conduction system pacing and its contemporary role in patients requiring permanent cardiac pacing.
PubMed: 38859643
DOI: 10.4070/kcj.2024.0113 -
Heart Rhythm Jun 2024Since 2000s CRT became a revolutionary therapy for heart failure with reduced left ventricular ejection fraction (HFrEF) and wide QRS. However, about one third of CRT... (Review)
Review
Since 2000s CRT became a revolutionary therapy for heart failure with reduced left ventricular ejection fraction (HFrEF) and wide QRS. However, about one third of CRT recipients do not show a favorable response. This review of current literature aims to better define the concept of CRT response/non-response. The diagnosis of CRT non-responder should be viewed as a continuum, and it cannot rely solely on a single parameter. Moreover, several patients' baseline features might predict an unfavorable response. A strong collaboration between HF specialists and electrophysiologists is key to overcoming this challenge with multiple strategies. In the contemporary era, new pacing modalities, such as His bundle pacing (HBP) and left bundle branch area pacing (LBBAP) represent a promising alternative to CRT. Observational studies demonstrated their potential; however, several limitations should be addressed. Large randomized controlled trials are needed to prove their efficacy in HFrEF with electromechanical dyssynchrony.
PubMed: 38848860
DOI: 10.1016/j.hrthm.2024.05.057 -
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 -
Computer Methods and Programs in... Aug 2024The excitable gap (EG), defined as the excitable tissue between two subsequent wavefronts of depolarization, is critical for maintaining reentry that underlies deadly...
BACKGROUND
The excitable gap (EG), defined as the excitable tissue between two subsequent wavefronts of depolarization, is critical for maintaining reentry that underlies deadly ventricular arrhythmias. EG in the His-Purkinje Network (HPN) plays an important role in the maintenance of electrical wave reentry that underlies these arrhythmias.
OBJECTIVE
To determine if rapid His bundle pacing (HBP) during reentry reduces the amount of EG in the HPN and ventricular myocardium to suppress reentry maintenance and/or improve defibrillation efficacy.
METHODS
In a virtual human biventricular model, reentry was initiated with rapid line pacing followed by HBP delivered for 3, 6, or 9 s at pacing cycle lengths (PCLs) ranging from 10 to 300 ms (n=30). EG was calculated independently for the HPN and myocardium over each PCL. Defibrillation efficacy was assessed for each PCL by stimulating myocardial surface EG with delays ranging from 0.25 to 9 s (increments of 0.25 s, n=36) after the start of HBP. Defibrillation was successful if reentry terminated within 1 s after EG stimulation. This defibrillation protocol was repeated without HBP. To test the approach under different pathological conditions, all protocols were repeated in the model with right (RBBB) or left (LBBB) bundle branch block.
RESULTS
Compared to without pacing, HBP for >3 seconds reduced average EG in the HPN and myocardium across a broad range of PCLs for the default, RBBB, and LBBB models. HBP >6 seconds terminated reentrant arrhythmia by converting HPN activation to a sinus rhythm behavior in the default (6/30 PCLs) and RBBB (7/30 PCLs) models. Myocardial EG stimulation during HBP increased the number of successful defibrillation attempts by 3%-19% for 30/30 PCLs in the default model, 3%-6% for 14/30 PCLs in the RBBB model, and 3%-11% for 27/30 PCLs in the LBBB model.
CONCLUSION
HBP can reduce the amount of excitable gap and suppress reentry maintenance in the HPN and myocardium. HBP can also improve the efficacy of low-energy defibrillation approaches targeting excitable myocardium. HBP during reentrant arrhythmias is a promising anti-arrhythmic and defibrillation strategy.
Topics: Humans; Bundle of His; Arrhythmias, Cardiac; Cardiac Pacing, Artificial; Electric Countershock; Heart Ventricles; Models, Cardiovascular
PubMed: 38823116
DOI: 10.1016/j.cmpb.2024.108239 -
Alternative Therapies in Health and... May 2024Right ventricular pacing (RVP) therapy is the conventional approach for atrioventricular block despite its propensity to cause electrical and mechanical dyssynchrony....
BACKGROUND
Right ventricular pacing (RVP) therapy is the conventional approach for atrioventricular block despite its propensity to cause electrical and mechanical dyssynchrony. This dyssynchrony increases the risk of atrial fibrillation and heart failure, eventually leading to left ventricular dysfunction. Left bundle branch pacing (LBBP) has recently emerged as a novel physiological pacing method. This study utilizes conventional ultrasound cardiography (UCG), two-dimensional speckle tracking imaging (2D-STI), and tissue Doppler imaging (TDI) to investigate the disparities in electrical and mechanical cardiac synchrony between LBBP and RVP patients.
METHODS
The retrospective analysis includes data from patients who underwent LBBP (n=50) and RVP (n=50) in Zhangjiagang First People's Hospital between January 2019 and June 2020, meeting the stipulated inclusion criteria. The study compares pacing parameters, UCG metrics, cardiac electrical and mechanical synchrony, pacing success rates, and safety events both pre-operation and at 3, 6, 12, and 24 months post-operation.
RESULTS
Implantation success rates for both RVP and LBBP groups were 100%, with 92% and 100% pacing success rates, respectively [P = .001 RR (95% CI) : 2.5 (1.5, 3.5)]. The LBBP group exhibited significant advantages over the RVP group throughout the follow-up period. LBBP patients displayed shortened QRS duration, reduced pacing thresholds and impedance, improved sensory function, lower serum NT-proBNP levels, and an increased proportion of NYHA class I patients [P = .003 RR (95% CI) : 1.6 (1.1, 2.3)]. Furthermore, left ventricular ejection fraction increased significantly, while left ventricular diastolic and end-systolic diameters decreased in the LBBP group compared to the RVP group [P = .004 RR (95% CI) : 1.7 (1.3, 2.2)]. The LBBP group also demonstrated shorter ventricular systolic synchrony parameters, including Tls-Dif, PSD, Trs-SD, Tas-SD, Tas-post, Ts-SD, and Ts-DIf, compared to the RVP group [P = .005 RR (95% CI) : 1.5 (1.2, 2.0)]. Notably, no postoperative complications occurred in either group, such as electrode displacement, lead thrombus attachment, incision bleeding, pocket hemorrhage, or infection. However, the readmission rates for heart failure were 16% in the RVP group and 2% in the LBBP group.
CONCLUSION
LBBP achieves physiological cardiac pacing, leading to significant improvements in serum NT-proBNP levels and cardiac function and enhanced ventricular contraction synchrony. Utilizing UCG, 2D-STI, and TDI for quantitative evaluation of cardiac electrical and mechanical synchrony proves to be a valuable clinical approach.
PubMed: 38814612
DOI: No ID Found -
Turkish Journal of Medical Sciences 2023Despite advancements in valve technology and increased clinical experience, complications related to conduction defects after transcatheter aortic valve implantation...
BACKGROUND/AIM
Despite advancements in valve technology and increased clinical experience, complications related to conduction defects after transcatheter aortic valve implantation (TAVR) have not improved as rapidly as expected. In this study, we aimed to predict the development of complete atrioventricular (AV) block and bundle branch block during and after the TAVR procedure and to investigate any changes in the cardiac conduction system before and after the procedure using electrophysiological study.
MATERIALS AND METHODS
A total of 30 patients who were scheduled for TAVR at our cardiovascular council were planned to be included in the study. TAVR was performed on patients at Erciyes University Medical Faculty Hospital as a single center between May 2019 and August 2020 Diagnostic electrophysiological study was performed before the TAVR procedure and after its completion. Changes in the cardiac conduction system during the preprocedure, intra-procedure, and postprocedure periods were recorded.
RESULTS
Significant increases in baseline cycle length, atrial-His (AH) interval, his-ventricular (HV) interval and atrioventricular (AV) distance were observed before and after the TAVR procedure (p = 0.039, p < 0.001, p = 0.018, p < 0.001, respectively). During the TAVR procedure, the preprocedural HV interval was longer in patients who developed AV block and bundle branch block compared to those who did not and this difference was statistically significant (p = 0.024). ROC curve analysis revealed that a TAVR preprocedure HV value >59.5 ms had 86% specificity and 75% sensitivity in detecting AV block and bundle branch block (AUC = 0.83, 95% CI: 0.664-0.996, p = 0.013). The preprocedure HV distance was 98 ± 10.55ms in the group with permanent pacemaker implantation and the mean value in the group without permanent pacemaker implantation was 66.27 ± 15.55 ms, showing a borderline significant difference (p = 0.049).
CONCLUSION
The prolongation of HV interval in patients with AV block and bundle branch block suggests that the block predominantly occurs at the infra-hisian level. Patients with longer preprocedural HV intervals should be closely monitored for the need for permanent pacemaker implantation after the TAVR procedure.
Topics: Humans; Transcatheter Aortic Valve Replacement; Male; Female; Pacemaker, Artificial; Aged; Aged, 80 and over; Atrioventricular Block; Bundle-Branch Block; Aortic Valve Stenosis; Electrocardiography; Postoperative Complications; Heart Conduction System
PubMed: 38813482
DOI: 10.55730/1300-0144.5750 -
Journal of Cardiovascular Development... May 2024Cardiac resynchronization therapy (CRT) significantly improves clinical outcomes in patients with ventricular systolic dysfunction and dyssynchrony. Biventricular pacing... (Review)
Review
Cardiac resynchronization therapy (CRT) significantly improves clinical outcomes in patients with ventricular systolic dysfunction and dyssynchrony. Biventricular pacing (BVP) has a class IA recommendation for patients with symptomatic heart failure with reduced ejection fraction (HFrEF) and left bundle branch block (LBBB). However, approximately 30% of patients have a poor therapeutic response and do not achieve real clinical benefit. Pre-implant imaging, together with tailored programming and dedicated device algorithms, have been proposed as possible tools to improve success rate but have shown inconsistent results. Over the last few years, conduction system pacing (CSP) is becoming a real and attractive alternative to standard BVP as it can restore narrow QRS in patients with bundle branch block (BBB) by stimulating and recruiting the cardiac conduction system, thus ensuring true resynchronization. It includes His bundle pacing (HBP) and left bundle branch area pacing (LBBAP). Preliminary data coming from small single-center experiences are very promising and have laid the basis for currently ongoing randomized controlled trials comparing CSP with BVP. The purpose of this review is to delve into the emerging role of CSP as an alternative method of achieving CRT. After framing CSP in a historical perspective, the pathophysiological rationale and available clinical evidence will be examined, and crucial technical aspects will be discussed. Finally, evidence gaps and future perspectives on CSP as a technique of choice to deliver CRT will be summarized.
PubMed: 38786966
DOI: 10.3390/jcdd11050144 -
JACC. Case Reports Jun 2024We present an unusual case of alternating left anterior and left posterior fascicular block. Given the known risk for progression to complete atrioventricular block with...
We present an unusual case of alternating left anterior and left posterior fascicular block. Given the known risk for progression to complete atrioventricular block with alternating right bundle and left bundle branch block, we performed an electrophysiological study. Findings were consistent with infra-Hisian disease, and the patient underwent pacemaker implantation.
PubMed: 38779552
DOI: 10.1016/j.jaccas.2024.102363