To what extent does prior antimicrobial therapy affect the diagnostic performance of radiolabeled leukocyte scintigraphy in infective endocarditis?

AIMS: This prospective, single-center study sought to assess to what extent there is interference between the hybrid technique of single-photon emission tomography-computed tomography with technetium99m-hexamethylpropyleneamine oxime-labeled leukocytes (99mTc-HMPAO-SPECT/CT) and antimicrobial therapy in patients with infective endocarditis (IE). METHODS AND RESULTS: During the years 2015-2019, we enrolled 205 consecutive adults with suspected IE, all underwent 99mTc-HMPAO-SPECT/CT. The study population was divided into those who had received antimicrobial therapy up to 30 days prior to 99mTc-HMPAO-SPECT/CT (group 1, n = 96) and those who had not (group 2, n = 109). Patients were prospectively observed for 12 ± 10 months. Group 1 presented higher positive predictive values (91.89% vs. 60.00%, = 0.001), and decreased negative predictive values (77.97% vs. 90.54%, P = 0.04). Patients treated with antimicrobial therapy displayed false-negative 99mTc-HMPAO-SPECT/CT results more often [odds ratio (OR), 4.63; 95% confidence interval (CI), 1.41-15.23, P = .01], particularly when intravenous (OR 5.37; 95% CI 1.73-16.62, P = .004), definite (OR 9.43; 95% CI 2.65-33.51, P = .001), and combination antibiotic regimens (OR 8.1; 95% CI 2.57-25.64, P = .001) had been administered. CONCLUSION: Prior antibiotic therapy affects 99mTc-HMPAO-SPECT/CT diagnostic properties. Patients treated with antimicrobial therapy display false-negative 99mTc-HMPAO-SPECT/CT results more often, especially if intravenous, definite, or combination regimens are administered.

Mechanical extraction of implantable cardioverter-defibrillator leads with a dwell time of more than 10 years: insights from a single high-volume centre.

AIMS: To analyze and compare the effectiveness and safety of transvenous lead extraction (TLE) of implantable cardioverter-defibrillator (ICD) leads with a dwell time of >10 years (Group A) vs. younger leads (Group B) using mechanical extraction systems. METHODS AND RESULTS: Between October 2011 and July 2022, we performed TLE in 318 patients. Forty-six (14.4%) extracted ICD leads in 46 (14.5%) patients that had been implanted for >10 years. The median dwell time of all extracted ICD leads was 5.9 years. Cardiovascular implantable electronic device-related infection was an indication for TLE in 31.8% of patients. Complete ICD leads removal and complete procedural success in both groups were similar (95.7% in Group A vs. 99.6% in Group B, P = 0.056% and 95.6% in Group A vs. 99.6% in Group B, P = 0.056, respectively). We did not find a significant difference between major and minor complication rates in both groups (6.5% in Group A vs. 1.5% in Group B and 2.2% in Group A vs. 1.8% in Group B, P = 0.082, respectively). One death associated with the TLE procedure was recorded in Group B. CONCLUSION: The TLE procedures involving the extraction of old ICD leads were effective and safe. The outcomes of ICD lead removal with a dwell time of >10 years did not differ significantly compared with younger ICD leads. However, extraction of older ICD leads required more frequent necessity for utilizing multiple extraction tools, more experience and versatility of the operator, and increased surgery costs.

The usefulness of echo-based hemodynamic parameters in cardiac resynchronization therapy with conduction system pacing for optimal device programing.

BACKGROUND: His bundle pacing (HBP) has proved to be a valuable alternative enabling the physiological activation of cardiac contraction in cardiac resynchronization therapy (CRT). At present, however, little is known about the optimal method of programming of the His bundle-paced CRT systems in terms of achieving the best cardiac output. AIM: The aim of this study was to evaluate the impact of cardiac resynchronization therapy with conduction system pacing (CRT+CSP) on echo-based hemodynamic parameters in the early post-operative measurements. METHODS: The study enrollment criteria included: permanent atrial fibrillation, heart failure and bundle branch block. All patients underwent implantation of CRT + HBP. During the post-operative phase, we aimed to optimize HOT-CRT settings in order to achieve the greatest cardiac output assessed by complex echocardiographic measurements. RESULTS: The study included 21 patients, mean age 71.2 (6.3) years, predominantly men (71.4%) with non-ischemic cardiomyopathy 62%. All patients had heart failure with NYHA functional class III and IV (81%). Mean left ventricular ejection fraction was 27.5 (9.7%). The mean duration of the QRS complex was 148.8 ms. The effects of resynchronization pacing: HBP alone, HBP with left ventricular pacing, HBP with biventricular pacing (BiV) and BiV without HBP ​​were analyzed consecutively. HBP combined with left ventricular pacing demonstrated the best hemodynamic response. CONCLUSION: His bundle pacing coupled with LV pacing proved to be the most advantageous pacing program setting with regard to cardiac output. Moreover, it performed better than biventricular pacing and significantly better than RV pacing.

The electrocardiographic interpretation of ventricular pacing suppression algorithms in the pacemaker.

Algorithms designed to reduce the right ventricular (RV) pacing burden are widely available in modern dual-chamber implantable pacing devices. These algorithms allow the atrioventricular delay for sensed ventricular events to be longer than for ventricular paced events. However, since these features are unique to pacemaker manufacturers, they often produce unfamiliar electrocardiographic (ECG) appearances that suggest pacemaker dysfunction. We describe a Vp suppression algorithm used in Biotronik dual-chamber pacemakers and implantable cardioverter-defibrillator devices.

Thoracic impedance measurement in heart stimulation and cardiac arrhythmias.

The electrocardiogram (ECG) interpretation in patients with implantable cardioverter defibrillator (ICD) is often a puzzling problem. The difficulty of the device function evaluation further increases in the presence of unfamiliar timing cycles and additional functions. We present an interesting ECG with a special function of a Biotronik ICD devices called the thoracic impedance monitoring, and demonstrate its behavior in a patient with atrial fibrillation, pacing beats, ventricular ectopic beats, and couple of ventricular beats. This report shows unexceptional occurrence of tricky ECG finding in patient with Biotronik ICDs.

Transvenous extraction of very old (over 20-year-old) pacemaker leads using mechanical systems: Effectiveness and safety.

OBJECTIVE: To analyze and compare the effectiveness and safety of transvenous lead extraction (TLE) with mechanical systems of pacing leads older than 20 years (group A) versus younger leads (group B). METHODS: We performed TLE of 591 pacing leads in 377 patients. Fifty (8.5%) leads in 43 (11.4%) patients were implanted for equal to or more than 20 years. The mean dwell time of all extracted leads was 8.9 years (range, 0.1-36.0). Infection related to cardiovascular implantable electronic device was an indication for TLE in 18.3% of patients. RESULTS: Complete lead removal and complete procedural success rates were similar between both groups (94.7% in group A vs 97.1% in group B, P = 0.445, and 90.7% in group A vs 95.8% in group B, P = 0.329, respectively). Incomplete lead removal in group A was observed only in leads older than 20 years. Removal of leads in group A was associated with significantly longer fluoroscopy time compared with group B (4.6 vs 1.9 minutes, P < 0.001). We did not find a significant difference in major and minor complication rates between groups (2.3% in group A vs 0.9% in group B and 2.3% in group A vs 2.2% in group B, P = 0.687, respectively). There were no deaths associated with the TLE procedure within 30 days after the procedure in either group. CONCLUSION: This study shows that TLE of leads older than 20 years conducted at an experienced center seems to be comparably safe and effective as extraction of younger leads but requires longer fluoroscopy time.

Cardiac resynchronization therapy with His bundle pacing.

AIMS: A novel therapy offering cardiac resynchronization therapy (CRT) with an additional lead placed in His bundle has been reported in a few case reports and case series as improving the hemodynamical and clinical condition of patients with permanent atrial fibrillation (AF) in whom other therapeutic methods have not been successful. METHODS: Fourteen consecutive patients with permanent AF, heart failure (HF), bundle branch block (BBB) with QRS complex width >130 ms, and impaired left ventricular ejection fraction (LVEF) underwent implantation of implantable cardioverter defibrillator (ICD)/CRT systems with His bundle pacing (HBP). During the follow-up, we assessed the efficacy of ICD/CRT systems with HBP in HF treatment. RESULTS: The study cohort consisted of 14 patients with the mean age of 67.35 ± 10 years. The mean duration of QRS was 159.2 ± 28.6 ms, mean LVEF was 24.36 ± 10.7%, and mean follow-up duration was 14.4 months. One patient died due to HF aggravation during the follow-up. In the remaining 13 patients, the mean LVEF significantly improved from 24% to 38%, P = 0.0015. The left ventricular end-diastolic dimension decreased from 72 mm to 59 mm, P < 0.001; left ventricular end-systolic dimension decreased from 59 mm to 47 mm, P = 0.0026. The mean QRS duration shortened from 159 ms to 128 ms, P = 0.016. The mean percentage of HBP reached 97%. As a result, 92.3% of patients demonstrated significant improvement in the New York Heart Association functional class, P < 0.001. CONCLUSION: The use of atrial channel for HBP, choice of optimal ICD/CRT pacing configuration, and optimization of pharmacological therapy resulted in a substantial narrowing of QRS width and clinical improvement in left ventricular mechanical function during the follow-up.

Pacing spikes following QRS complexes: What is the mechanism?

The electrocardiogram (ECG) interpretation in patients with implantable cardioverter defibrillator (ICD) is often a puzzling problem. The difficulty of the device function evaluation further increases in the presence of unfamiliar timing cycles and additional functions. Authors present a special function of a Biotronik ICD devices called the thoracic impedance monitoring, and demonstrate its behavior in a patient with sinus rhythm, ventricular ectopic beats, and ventricular tachycardia episode. This report shows unexceptional occurrence of tricky ECG finding in patient with Biotronik ICD.

Switch between AAI and DDD mode pacing-What is the mechanism?

The electrocardiogram (ECG) interpretation in patients with implantable pacemaker is often a perplexing problem. The difficulty in the device evaluation increases in the presence of novel timing cycles and additional functions. Authors describe a special function frequently encountered in Medtronic dual-chamber pacemakers and implantable cardioverter-defibrillator devices called managed ventricular pacing (MVP) and demonstrate its performance in the patient with undersensing episodes in ventricular channel. Intermittent ventricular undersensing in the device with MVP feature turned on caused repetitive mode switches between AAI and DDD mode. This report shows unexceptional occurrence of tricky ECG findings in patient with Medtronic dual-chamber device.

Transvenous extraction of 3-year-old Seldinger guide wire lost in venous system and causing superior vena cava syndrome - rare complication of implantable cardioverter-defibrillator implantation.

A CASE REPORT: A 65-year-old male patient underwent left-sided placement of implantable cardioverter-defibrillator. At three years after implantation he emerged complaining on left upper limb and left-sided neck edema. Left brachicephalic vein thrombosis due to device leads was recognized. The attending cardiologist referred the patient to university radiology department for venous angioplasty but the patient was admitted to cardiology department. Coronary angiography was performed due to suspicion of ischemic heart disease. However, it showed the presence of foreign body in cardiovascular system - completely intravascular round-tipped guide wire used in Seldinger technique for insertion of the endocardial lead abandoned in left subclavian vein and reaching to superior vena cava. Patient was transferred to third-degree reference lead extraction center. The procedure was performed under general anesthesia in hybrid operating room. Via femoral vein access we introduced Needle's Eye Snare and grasped the guide wire. Then, using polytetrafluoroethylene sheath the tissue adhesions were dissected and the complete guide wire was retrieved.

Analysis of electrical lead failures in patients referred for transvenous lead extraction procedures.

INTRODUCTION: We evaluated the influences of selected factors on electrical lead failure (ELF) occurrence in patients referred for transvenous lead extraction (TLE) procedures. METHODS AND RESULTS: The study cohort consisted of 432 patients referred for TLE procedures due to various indications (42 - lead-dependent infective endocarditis, 47 - pocket infection, 343 - noninfectious indications) with a total of 804 endocardial leads. In the analyzed group, there were 192 patients with ELF, denoted as group ELF(+) (200 malfunctioning endocardial leads). The percentage of women was higher in the ELF(+) group than in the ELF(-) group (42.7% vs 30.0%; P  =  0.006). The ELF(+) patients had more endocardial leads implanted via subclavian vein puncture (80.0% vs 72.4%; P  =  0.032), had more indwelling leads in the cardiovascular system (1.94 vs 1.8; P  =  0.03), were older (68.9 vs 66.0 years old; P  =  0.028), and had better left ventricular ejection fractions than the ELF(-) patients (48.0% vs 40.7%; P < 0.001). The time interval to ELF occurrence was significantly longer for pacing leads than for cardioverter-defibrillator leads (95.7 vs 65.7 months; P  =  0.016). The most important factor associated with ELF was subclavian vein puncture, increasing the risk of ELF occurrence by 2.5-fold and 2.7-fold in the univariate and multivariate Cox proportional hazards regression models, respectively. The presence of a cardioverter-defibrillator lead increased the risk of ELF by 1.9-fold and 2.7-fold in the univariate and multivariate models, respectively. CONCLUSION: The most significant factors predisposing patients to ELF are the lead implantation approach and the presence of a cardioverter-defibrillator lead.

Inhibition of left ventricular stimulation due to left ventricular lead failure and the left ventricular T-wave protection algorithm in patient with cardiac resynchronization therapy and pacemaker dependency.

The electrocardiogram (ECG) interpretation in patients with cardiac resynchronization therapy (CRT) is often a perplexing problem. The difficulty in the device evaluation increases in the presence of unfamiliar timing cycles and a lead dysfunction. Authors describe a special function of a Biotronik CRT devices called the left ventricle T-wave protection (LVTP), and demonstrate its behavior in a patient with left ventricular (LV) lead failure. This report shows that sometimes it might be difficult to understand the loss of resynchronization in 12-lead ECG when LVTP feature is on, and a malfunction of left ventricular lead sensing occurs.

Cardiac resynchronization therapy with His bundle pacing as a method of treatment of chronic heart failure in patients with permanent atrial fibrillation and left bundle branch block.

CRT is a therapeutic option for patients with heart failure, sinus rhythm, prolonged QRS complex duration and reduced ejection fraction. We present a case of 71-year-old woman with dilated cardiomyopathy, NYHA functional class III and AF. We implanted CRT combined with direct His-bundle pacing. The indication for such a therapy was a left bundle branch block with a QRS complex of 178ms and a left ventricular EF of 15%, left ventricular end-diastolic diameter (LVEDD) of 75mm. After 8months of follow-up the LVEDD was 60mm with EF 35-40%.

Inhibition and restoration of CRT pacing - What is the mechanism?

The electrocardiogram (ECG) interpretation in patients with cardiac resynchronization therapy (CRT) may be challenging. The difficulty increases if not well-known pacemaker algorithm is turned on. We show a T-wave protection algorithm (LVTP) in a patient with CRT. Accelerated sinus rhythm and intermittent oversensing in left ventricular channel resulted in loss of CRT pacing. The restoration of biventricular pacing occurred when atrial rate decreased. We provide detailed descriptions of the electrocardiogram and intracardiac electrogram. LVTP may confuse ECG examination interpretation, especially in patients with accelerated atrial rhythm and oversensing in left ventricular channel.

Implantable cardioverter defibrillator does not cure the heart.

A man with non-ischemic cardiomyopathy, EF 22%, permanent AF and ICD was admitted for elective device replacement. The need for the optimization of the ventricular rate and avoidance of right ventricular pacing made it necessary to up-grade the existing pacing system using direct His bundle pacing and dual chamber ICD. This enabled the regularization of ventricular rate, avoiding the RV pacing and optimize the beta-blocker dose. The one month follow-up already showed reduction in left ventricle diameter, improvement in ejection fraction, NYHA class decrease to II. The His bundle pacing enabled the optimal treatment of the patient resulting in excellent clinical improvement.

Venous stenosis and occlusion in the presence of endocardial leads in patients referred for transvenous lead extraction.

Objective The aim of this study was to evaluate the incidence of venous stenosis and occlusion (VSO) in patients referred for transvenous lead extraction (TLE) with regard to the indications for this treatment and to analyse the influence of VSO on efficacy, complications and technical challenges of TLE procedures. Methods The material consists of 133 consecutive TLE procedure records. The contrast venography examination of the ipsilateral access vein was performed prior to the operation. The whole study population was divided into two subgroups, based on the presence (subgroup I) or absence (subgroup II) of VSO. Results Phlebography was performed in 133 patients with age ranging from 25.7 to 86.1 years, 44 female (33.1%). The VSO was confirmed in 48 (36.1%) patients - subgroup I. Most of the patients were referred to TLE due to non-infectious reasons (100 pts-75.2%). The absence of VSO was observed substantially more frequently in patients with diabetes (P = 0.02). Procedural success rate reached 93.3% in subgroup I and 98.8% in subgroup II (P = 0.1). There was no significant difference in the use of advanced tools and alternative access sites. Conclusion The presence of VSO can be expected in one third of patients referred for lead extraction. There is no association between indication for TLE (infected or noninfected lead extraction) and the incidence of VSO. Diabetes proved to have a protective effect on venous patency in the previously mentioned group. VSO does not influence the effectiveness, safety, and the use of additional tools during TLE procedures.

Sex differences in venous stenosis and occlusion in patients with endocardial leads.

Venous stenosis and occlusion (VSO) in the presence of endocardial leads constitute one of the complications of permanent cardiac pacing. At present there are no scientific reports on the influence of sex on the incidence of VSO. AIM: The aim of the study was to examine the influence of sex on the incidence of VSO in patients with earlier implanted endocardial leads in a single-center retrospective analysis. MATERIALS AND METHODS: The material consists of 284 records of consecutive patients admitted to hospital to undergo electrotherapy procedures. In all patients a contrast venography for ipsilateral venous confluence was performed before the procedure. Patients were divided into two groups according to sex criterion. Groups were compared concerning following parameters: demographic characteristics, cardiac implantable electronic device (CIED) characteristics, comorbidities, CHA2DS2-VASc score, selected risk factors for VSO. RESULTS: Group I consist of 101 females, whereas group II consist of 183 males. Both groups did not differ significantly for age, number of implanted endocardial leads and lead dwell time. In the cohort males were with significantly greater burden of morbidity, reflected by the mean result of CHA2DS2-VASc (P=0.0098). In males there was significantly more often chronic heart failure (P<0.0001), chronic obstructive pulmonary disease (P=0.0450) and tobacco use (P=0.0159). Males had more ICD implanted than females (P=0.0270). In the examine cohort 88 patients (31%) had VSO. There was no statistically significant difference in terms of presence of VSO between females and males (P=0.4685). The detailed analysis of the patients with VSO divided according to sex revealed higher morbidity in males. CONCLUSIONS: The equality of VSO incidence in groups of males and females along with the predominance of factors protecting against VSO in group of males support the assumption that female gender is a protective factor against the development of VSO, equally as known protective factors in males.

The analysis of indications and early results of transvenous lead extraction in patients with a pacemaker, ICD and CRT - single-center experience.

INTRODUCTION: Transvenous lead extraction (TLE) is a recognized method of treatment in the case of permanent stimulation complication. OBJECTIVES: The objective of this study was to analyse the indications and presentation of the early experience of TLE procedures in a group of patients with old pacing systems. PATIENTS AND METHODS: Patients with a relevant history of stimulation (at least 12 months in case of a pacemaker) qualified for the research. Indications, effectiveness and complications of TLE procedures were analysed. RESULTS: Two hundred patients at the age of 66.4 (19.1-86.2 years) were enrolled and 278 leads with dwell time 76.2 months (2.1-327.4) were removed. The indications for TLE were: lead-dependent infective endocarditis in 13 cases (6.5%), pocket infection in 29 cases (14.5%), lead damage in 120 cases (60.0%), and upgrade of device system in 38 cases (19.0%). Manual traction was used to remove 66 active fixation leads (23.7%). A femoral approach was required to extract 4 leads (1.4%). Two hundred and eight leads (74.8%) were extracted using the mechanical (Cook) system and subclavian approach. Laser technique, and an electrosurgical sheath were not used. Complete procedural success was achieved in 96% of cases and overall clinical success was 98.5%. Complication rate was 5.5% (11 patients): minor and major complication rate was 3.0% (6 patients) and 2.5% (5 cases), respectively. Low body mass index (BMI) was associated with a higher rate of complications. CONCLUSIONS: The dominant indication to TLE procedures was lead dysfunction. Transvenous lead extraction has a high success rate and a low complication rate. Low BMI increased the complication rate.

Management of Arrhythmias and Conduction Disorders in Amyloid Cardiomyopathy.

Cardiac amyloidosis, a condition characterized by abnormal protein deposition in the heart, leads to restrictive cardiomyopathy and is notably associated with an increased risk of arrhythmias and conduction disorders. This article reviews the current understanding and management strategies for these cardiac complications, with a focus on recent advancements and clinical challenges. The prevalence and impact of atrial arrhythmias, particularly atrial fibrillation, are examined, along with considerations for stroke risk and anticoagulation therapy. The article also addresses the complexities of managing rate and rhythm control, outlining the utility and limitations of pharmacological agents and interventions such as catheter ablation. Furthermore, it reviews the challenges in the treatment of ventricular arrhythmias, including the contentious use of implantable cardioverter-defibrillators for primary and secondary prevention. Individualized approaches, considering the unique characteristics of cardiac amyloidosis, are paramount. Continuous research and clinical exploration are essential to refine treatment strategies and improve outcomes in this challenging patient population.

Endocardial lead insulation wear in a scanning and optical microscope.

BACKGROUND: The path and interaction of leads within the cardiovascular system are influenced by various factors, including the implantation technique. Furthermore, the multifaceted composition of these leads, often comprising multiple materials, can contribute to their potential degradation and wear over time. OBJECTIVES: Our aim was to investigate the wear of lead insulation following the removal of transvenous leads and pinpoint the regions of the lead most vulnerable to damage. MATERIAL AND METHODS: We undertook a prospective analysis of patients from a single tertiary center who underwent transvenous lead explantation (TLE) between October 1, 2013, and July 31, 2015. Specifically, our examination focused on endocardial leads removed using simple screw-out and gentle traction techniques. Subsequent lead evaluations were conducted utilizing scanning electron and optical microscopes. RESULTS: Among the 86 patients who underwent the TLE procedure, 26 patients (30%) required the removal of 39 leads through simple traction. Inspection using scanning electron microscopy consistently indicated insulation damage across all leads. A total of 347 damaged sites were identified: 261 without lead unsealing and 86 exhibiting unsealing. Notably, the sections of the leads located within the intra-pocket area demonstrated the highest vulnerability to damage (odds ratio (OR): = 9.112, 95% confidence interval (95% CI): 3.326-24.960), whereas the intravenous regions displayed the lowest susceptibility (OR: 0.323, 95% CI: 0.151-0.694). CONCLUSIONS: Our study reveals that all evaluated leads exhibited insulation damage, with the intra-pocket segments manifesting a notably higher prevalence of damage than the intravenous segments.