Dual-chamber Pacemaker Implantation Research Articles

Idiopathic brachial plexopathy after pacemaker implant.

A middle-aged woman presented with symptomatic complete heart block and underwent an uneventful dual chamber pacemaker implantation. Three weeks post procedure, she developed left arm pain and weakness, with neurological localization to the lower trunk of left brachial plexus. Possibilities of traumatic compression by the device/leads or postoperative idiopathic brachial plexopathy were considered. After ruling out traumatic causes, she was started on oral steroids, to which she responded remarkably. This case highlights the importance of recognizing this rare cause of brachial plexopathy following pacemaker implantation, because not only does an expedited diagnosis and medical treatment lead to prompt recovery with minimal neurological deficits, but it also circumvents an unnecessary surgical re-exploration.

Hemostasis system in patients with bradycardias after the implantation of dual-chamber pacemakers

Introduction: As with many other surgical interventions, the implantation of a pacemaker may be associated with adverse outcomes in the immediate or distant period. The search for probable risk factors of adverse outcomes may promote the development of effective and safe management methods of patients with pacemaker postoperatively. One of the important directions in this field is the investigation of the effect of pacemaker implantation on the hemostasis system of these patients.
 Aim: To evaluate the effect of the implantation of dual-chamber pacemaker on the hemostasis system of patients with different kinds of bradyarrhythmias and to determine probable risk factors for unfavorable outcomes in this groupof patients.
 Materials and methods: The study was performed with the financial support of the Russian Foundation for Basic Research within the Scientific Project No. 19-315-90109. The prospective study (ClinicalTrials.gov ID, NCT04499612) enrolled 61 patients (men, 45.9%) with a mean age of 71.5 8.8 years. The groupwho received surgical treatment included 23 patients with atrioventricular (AV) block and 25 patients with sick sinus syndrome (SSS), and the groupwith conservative treatment included 13 patients with AV blocks and SSS, but without indications for pacemaker implantation. Anticoagulant therapy was given to one patient with AV block, 12 patients with SSS, and five patients with conservative therapy. All the remaining patients received antiplatelet therapy. The surgical groupunderwent ultrasound examination of the veins of the upper and lower extremities and sampling of peripheral venous blood before and 7 days after pacemaker implantation to determine the level of fibrinogen (FI) and activity of blood coagulation factors VIII (FVIII) and IX (FIX), antithrombin III (AT III), and protein C. In the conservative group, a similar examination was conducted only on inclusion in the study.
 Results: In patients with AV block, a significant increase in blood fibrinogen was noted at 7 days after surgery (р=0.042). In the intergroupcomparison, the activity of AT III after the implantation was higher in the surgical groupthan in the conservative group(р=0.018 and р=0.006, respectively). After surgery, the activity of FVIII and FIX was lower in patients with SSS on anticoagulant therapy than in patients with antiplatelet therapy (р=0.048 and р=0.015, respectively). Based on the receiver operating characteristics analysis, the risk factors for lethal outcomes were reduced activity of AT III in patients with AV block and increased activity of FIX in patients with SSS.
 Conclusions: The balance of the hemostasis system in patients with AV blocks on antiplatelet therapy was shifted toward hypercoagulation within at least 7 days after pacemaker implantation. The use of anticoagulants in patients with SSS caused a shift toward hypocoagulation. The reduced activity of AT III in patients with AV block and increased activity of FIX in patients with SSS are prognostic factors for lethal outcomes.

711 A rare case of takotsubo syndrome induced by pacemaker implantation

Abstract Aims Takotsubo syndrome (TTS) is an acute cardiac condition characterized by a temporary wall motion abnormality of the left ventricle that mimics an acute coronary syndrome (ACS). TTS usually occurs following emotionally or physically triggering event. We report a rare case of Takotsubo syndrome following a pacemaker implantation. Methods and results A 77-year-old woman was admitted to our hospital with a third-degree atrioventricular block. She was asymptomatic with a history of hypertension, diabetes, hyperlipidaemia and extrapyramidal syndrome. Laboratory tests reported High-Sensitive cardiac Troponin T (HS-cTnT) 32.9 ng/L (ULN <14), creatine kinase muscle and brain (CK-MB) 4.1 ng/mL (ULN < 4.94) and NT-proB-type Natriuretic Peptide (NT-proBNP) 1465 pg/ml (ULN < 125). Echocardiography showed a normal left ventricular ejection fraction (EF = 58%) (Figure 2A). The patient underwent dual chamber pacemaker implantation without immediate complications. Three days later, a routine ECG showed new T wave inversions (Figure 1), in absence of symptoms. Echocardiography revealed apical akinesia, with ‘apical ballooning’ (EF 30%) (Figure 2B). Serum cardiac markers were increased (CK-MB 8.2 ng/ml, HS-cTnT 189.7 pg/ml, NT-proBNP 15 005 pg/ml. A coronary angiography excluded obstructive coronary artery disease (Figure 3). Given the impossibility of carrying out a cardiac RMI for the recent pacemaker implantation and after exclusion of other diagnoses, pacemaker implantation induced Takotsubo syndrome was suspected. Conclusions The trigger of this case of TTS was the pacemaker implantation, a relatively brief and painless procedure that, in her case could have constitute a considerable emotional and physical stress. To the best of our knowledge 13 cases of TTS after pacemaker implantation have been described to date. Of those cases, four had an asymptomatic course. Therefore, the real incidence of TTS following pacemaker implantation may be underestimated and ECG and echocardiography should always be performed after pacemaker implantation.

656 Cough, a rare and not well recognized symptom of lead perforation

Abstract Aims Along with relevant progress in technology, pacemaker implantation is continuously improving its safety and efficacy in treating patients with bradyarrhythmias. Despite this, this procedure has several complications, including haematoma, pneumothorax, lead dislodgement, infection, lead perforation, and tamponade. Methods and results A 64-year-old woman underwent loop recorder implantation, after recurrent loss of consciousness, in order to assess arrhythmic causes of syncope. Two weeks later, an episode of paroxysmal complete AV block, conditioning a pause of 3 s, was recorded. Thus, the patient was scheduled for urgent dual-chamber pacemaker implantation. No complication apparently occurred during the procedure. An active fixation ventricular lead was positioned in right ventricular septal apex while passive fixation atrium lead in the right appendage. Soon after implantation the patient started to suffer by non-productive cough, clearly related to ventricular stimulation, either in DDD or in VVI pacing modality. During spontaneous ventricular activation (RBBB) no symptoms occurred. Transthoracic echocardiography, performed the day after implantation, revealed a small pericardial effusion (diastolic diameter < 10 mm) along the apical segments, near the tip of the right ventricular lead. Suspicion of right ventricular lead perforation arised. The patient underwent urgent contrast chest CT confirming pericardial effusion, and showing an intramyocardium placement of the right ventricular apical lead. No active bleeding in pericardium was observed. Due to persistence of symptoms, we decided to perform right ventricular lead repositioning in right middle septum, with pericardiocentesis back-up promptly available. Post-procedure, palpitation, and cough abruptly disappeared. After 3 months follow-up, no significant symptoms were reported and pericardial effusion gradually disappeared. Conclusions We describe a singular case of cough, as atypical symptom immediately after pacemaker implantation. Pericardial effusion and contrast-CT showing intra-myocardial position of the tip guided our suspicion to a possible right ventricular lead microperforation. Although right ventricular lead parameters were completely normal this findings didn’t exclude RV perforation. The lead perforation is known as a rare complication of device implantation. Typical symptoms of RV lead perforation are chest pain and hypotension. The patient described in our case showed a haemodynamically stable pericardial effusion accompanied by non-productive cough, clearly time-related to RV stimulation. In literature, there is only another similar case report. The cough is a rare and not well recognized symptom of lead perforation. Early diagnosis of RV perforation allows to perform urgently and safely (pericardiocentesis back-up) lead replacement/repositioning. Echocardiography and contrast-CT could be useful in order to assess a possible pericardial effusion or intramyocardial/pericardial position of RV lead tip.

739 Atypical presentation of Takotsubo syndrome early after pacemaker implantation

Abstract Aims Takotsubo syndrome (TTS) is an acute stress-induced cardiomyopathy showing left ventricular (LV) dysfunction without obstructive coronary arteries disease. A sudden massive surge of circulatory catecholamines from an intense physical or emotional stress may play a central role in the pathogenesis of TTS. We report the case of an 87 years-old woman who developed TTS with uncommon presentation after permanent pacemaker (PM) implantation. Methods and results The patient was referred to our hospital for PM implantation because of advanced atrio-ventricular block (3:1). She suffered by rheumatoid arthritis (RA), arterial hypertension, and chronic kidney disease. Echocardiogram, performed before PM implantation, showed normal LV kinesis and normal ejection fraction (EF 60%). She was initially administered with infusion of Isoprenaline 2 mcg/min. The subsequent day, she underwent permanent dual-chamber pacemaker implantation without any complications. After 3 days, the patient complained severe asthenia and fever, together with increase of white blood cells and C reactive protein. Blood cultures were negative. We started antibiotic therapy and, suspecting a reactivation of RA, steroid therapy with infusion of methylprednisolone 40 mg/die. Electrocardiogram showed normal sinus rhythm and paced ventricular rhythm. PM interrogation showed normal function. Surprisingly, echocardiogram showed LV dysfunction with apical and medium segments akinesia, and severe EF reduction (35%). Coronary angiography documented absence of coronary obstructive lesions, assessing diagnosis of TTS. The patient was discharged 1 week after admission in good clinical condition. One week later, an echocardiogram showed apical akinesia, partial recovery of medium segments motility, and slight increase of EF (40%). The excess of catecholamines could lead to decreased cardiac muscular function and to spasm of coronary arteries: these events can lead to acute heart failure and decrease of LVEF. Furthermore, about 90% of patients with TTS are women, especially in postmenopausal period. Peculiarities of this case were the atypical symptoms of TTS and the combination of different predisposing stressors factors: female sex in postmenopausal period, anamnesis of chronic inflammatory disease, use of stress-inducing drugs (methylprednisolone and isoprenaline, the last associated with TTS after PM-implantation), atrio-ventricular block itself, and PM implantation procedure. Our findings remark that even a low-risk procedure could be a possible cause of TTS in patient with such risk factors. In our opinion, in this subset of patients, conscious sedation could be useful to reduce the stress load, together with an early procedure and consequently the minimal use of exogenous stress drugs like Isoprenaline, even if the patient is in a good clinical condition. Conclusions This case highlights TTS as a potential complication after PM implantation, especially in post-menopausal women with high pre-existing stress load.

Abstract 16643: Pacemaker For First Degree AV Block Without Bradycardia: Pseudo-pacemaker Syndrome

Case Presentation: An 86 year old man underwent PCI of distal LAD for severe single vessel coronary artery disease identified after a high risk pharmacologic nuclear stress test (evaluation of exertional fatigue prior to abdominal aortic aneurysm surgical repair). ECHO was consistent with preserved LVEF (60-65%), moderate concentric LVH and mild left atrial enlargement. Less than a week after PCI, he presented to the emergency department for NYHA III dyspnea and fatigue. The patient was not taking any negative chronotropic medications. CT angiography of the chest excluded pulmonary edema, pneumonia and pulmonary embolism; repeat limited ECHO was unchanged. EKG showed first degree AV block (PR 400ms, figure 1). Severely prolonged PR interval with otherwise-unexplained exertional symptoms raised suspicion for pseudo-pacemaker syndrome. In the absence of an alternative cause of declining exertional tolerance, a dual chamber pacemaker with short programmed AV delay (<200ms) was implanted. The patient reported resolution of exertional fatigue and dyspnea on one-month followup. Discussion: Pseudo-pacemaker syndrome is a rare, infrequently reported, complication of first degree AV block with severely prolonged PR>300ms. P-wave at the end of the preceding T-wave suggests AV dyssynchrony (arrowhead, figure 1). Left atrial contraction against a closed mitral valve led to loss of atrial contribution to cardiac output, and elevated left atrial pressure. These changes, accentuated by physiologic increase in heart rate on exertion, most likely caused symptoms in this patient. It is interesting that AV dyssynchrony in pacemaker syndrome is caused by the pacemaker (VVI pacing) whereas the AV dyssynchrony in pseudo-pacemaker syndrome from severely prolonged PR interval is treated with a pacemaker. In the appropriate clinical picture, it is an indication for dual-chamber pacemaker implantation for first degree AV block without bradycardia or pauses.

Abstract 11164: Better Electromechanical Synchrony During Left Bundle Branch Pacing and His Bundle Pacing as Compared to Right Ventricular Pacing in Atrioventricular Block

Objectives: To compare electromechanical ventricular synchrony when pacing from different sites including right ventricular apex pacing (RVAP), right ventricular septum pacing (RVSP), His Bundle pacing (HBP), left bundle branch pacing (LBBP) and RVSP during unipolar pacing from the ring electrode of LBBP lead (RVSP ring ) in each patient during implantation. Methods: Twenty patients with complete atrioventricular block (AVB) indicated for dual-chamber pacemaker implantation were included. Unipolar pacing at different sites including RVAP,RVSP,HBP,LBBP and RVSP ring were successively performed in each patient while pacing characteristics and echocardiogram parameters were collected and compared. Results: Similar to HBP, narrower paced QRSd was found in LBBP as compared to RVSP ring , RVSP and RVAP(p<0.001). LBBP showed comparable pacing parameters to RVAP or RVSP and were significantly better than HBP, with maintained cardiac function. For ventricular mechanical synchrony, TS-12-SD was significantly improved in LBBP(27.00±21.53ms) than RVAP(54.05±34.21ms, p=0.004) and RVSP(47.56±33.26ms, p=0.029) but similar to HBP or RVSP ring . Among these pacing strategies, negative values of interventricular mechanical delay(IVMD) were only identified in LBBP(-20.16±18.47ms), significantly different from RVAP(33.68±30.98ms), RVSP (21.68±22.02ms), HBP (4.74±19.04ms) and RVSP ring (14.56±26.76ms(all p<0.001). Using Pearson’s analysis, Sti-LVAT was found to be positively corelated with QRS, IVMD, TS-12-SD, LVEDV and LVESV while a negative relationship could be observed for LVEF. Conclusions: Similar to HBP, LBBP achieved better electrical and mechanical left ventricular synchrony than conventional RV pacing. For interventricular synchrony, only LBBP initiated earlier LV activation than RV among these pacing strategies, in consistent with the RBBB pattern of paced QRS during LBBP.

2021 PACES Expert Consensus Statement on the Indications and Management of Cardiovascular Implantable Electronic Devices in Pediatric Patients: Executive Summary.

2021 PACES Expert Consensus Statement on the Indications and Management of Cardiovascular Implantable Electronic Devices in Pediatric Patients: Executive Summary.

Predictors of heart failure hospitalization and cardiovascular mortality in patients with chronic right ventricle pacing

Abstract Background Left ventricle (LV) dysfunction after chronic right ventricle (RV) pacing, also known as pacemaker induced cardiomyopathy (PICM) is a relatively common finding, ranging from 15–20% of patients. It has been associated to a high burden RV pacing, age, male gender and intrinsic and paced QRS duration. However, clinical relevance of LV dysfunction in this population has not been studied. Purpose The aim of the study was to identify predictors of heart failure (HF) hospitalization and cardiovascular (CV) mortality in patients with RV pacing. Methods Retrospective and unicentric study. We studied 2418 patients undergoing single or dual-chamber pacemaker implantation between 2012–2018. Patients were included if they had an echocardiogram prior to implantation and a repeated echocardiogram >3 months after implantation. Baseline LV ejection fraction (LVEF) had to be >50%. PICM was defined as ≥10% decrease in LVEF, resulting in LVEF <50%. Alternative causes of LV dysfunction were excluded. Primary endpoint was heart failure hospitalization. Secondary endpoint was cardiovascular mortality. Competing-risk regression analysis was performed to identify predictors of HFH and CV mortality. Results Of 2418 patients, 495 meeting study criteria and 105 (21.2%) met PICM criteria. Follow-up period was 56.1±28.5months. There were no differences in basal LVEF (60.1±0.5% in non-PICM patients vs 59.5±0.5 in PICM patients, p=0.51). Mean LVEF at follow-up was 37.7±0.9 vs 56.7±0.3, p<0.001. After logistic multivariable analysis, factors associated with PICM were alcohol consumption (OR 3.0, 95% CI 1.1–8.0,p=0.032), right bundle branch block (RBBB) (OR 1.9, 95% CI 1.06–3.51,p=0.031), higher RV pacing burden (OR 1.0, 95% CI 1.0–1.1,p=0.008) and higher basal LV end-diastolic diameter (OR 1.1, 95% CI 1.0–1.1,p=0.016). HFH occurred in 144 patients (29.1%). Factors associated with HFH after multivariable analysis were any decrease in LVEF (LVEF>55% as reference: LVEF 46–55% (HR 2.1, 95% CI 1.3–3.3,p=0.002); LVEF 36–45% (HR=1.5, 95% CI 0.7–3.0; p=0.306), LVEF≤35% (HR 2.44, 95% CI 1.11–5.37,p=0.027), age (HR 1.0, 95% CI 1.0–1.1,p=0.037), alcohol consumption (HR 3.4, 95% CI 1.9–6.1,p<0.001), presence of atrial fibrillation (HR 1.7, 95% CI 1.06–2.70,p=0.027) and paced QRS duration (HR 1.0, 95% CI 1.0–1.02,p=0.031). CV mortality occurred in 54 patients (10.9%). Factors associated with CV mortality after multivariable analysis were a decrease in LVEF (LVEF 46–55% (HR 1.6, 95% CI 0.8–3.2,p=0.217); LVEF 36–45% (HR=1.6, 95% CI 0.6–4.2,p=0.33); LVEF≤35% (HR 4.6, 95% CI 2.0–10.7,p<0.001), RBBB (HR 2.1, 95% CI 1.1–3.9,p=0.026) and lower haemoglobin (HR 0.8, 95% CI 0.7–0.99,p=0.033). Conclusion In patients with RV pacing, factors associated with PICM were alcohol consumption, RBBB, RV pacing burden and basal LV end-diastolic diameter. HF hospitalization and CV mortality are common (29.1% and 10.9%). Any decrease in LVEF is associated with an increase in CV events. Funding Acknowledgement Type of funding sources: None.

Dual-chamber cardiac pacing effect on left and right atria morphometric parameters and function

Abstract Background Dual-chamber pacemaker implantation is a standard interventional treatment strategy for atrioventricular block (AVB) and sick sinus syndrome (SSS). It has been proven that a high percentage of right ventricular pacing might have detrimental effects on cardiac function. However, there is a lack of data on atrial pacing effect on left (LA) and right (RA) atria function. Purpose To assess the impact atrial pacing on left and right atria morphologic and functional parameters in patients after dual-chamber pacemaker implantation. Methods We conducted a prospective study that included patients who received a dual-chamber pacemaker for an indication of AVB or SSS. After signing of the informed consent pacemaker was programmed for base rate of 40 bpm and no rate response in case of clear AVB indication or for base rate of 60 bpm and rate response if indication was SSS. An transthoracic echocardiography was done the next day after pacemaker implantation and after one month at follow up (FU). During the FU the atrial pacing (AP) and ventricular pacing (VP) percentage were captured. To exclude the impact of right ventricular pacing, patients with high VP percentage (>40%) were excluded from analysis. Patients were divided into two groups – group A with high AP (>50%), and group B – low AP (<50%). LA expansion fraction reflecting reservoir function, emptying – reflecting conduit, and active emptying reflecting “atrial kick” were analysed. To compare means the Mann Whitney U test, and for categorical variables – X2 test were used. Results A total of n=100 patients underwent dual-chamber implantation and signed informed consent. Due to significant structural heart disease or reduced ejection fraction (<50%) 11 patients were excluded. Out of those, n=30 were excluded due to a high VP percentage. Group consisted of n=28 and group B of – n=31 patients. Average AP in group A was 66.2% and 5.0% in group B. The mean age (group A 73.6 SD 8.8 years vs group B 79.2 SD 7.3 years, p=0.197), gender distribution (group A males 45.5% vs group B 50.0%, p=0.773), and mean BMI (group A 26.5 SD 4.7 kg/m2 vs group B 29.2 SD 3.3 kg/m2, p=0.191) did not differ significantly between the two groups. The baseline LA and RA morphometric and functional parameters presented in figure 1 and did not differ significantly between the two groups. The change in LA and RA functional parameters presented in figure 2. Even though it did not reach statistical significance, a tendency for lower LA expansion fraction, active emptying fraction and LA ejection fraction were observed in group A. RA morphometric parameters did not change significantly between the two groups at FU. Conclusion A higher percentage of atrial pacing in dual-chamber pacemaker population could lead to impaired LA function over time. Though, longer observational period is needed. Funding Acknowledgement Type of funding sources: None. Figure 1Figure 2

Dual chamber pacemaker implantation in woman with twin pregnancy and Chagas cardiomyopathy guided by 2D transthoracic echocardiography

We present a case of 36-year-old woman with twin pregnancy, Chagas cardiomyopathy and history of multiple episodes of dizziness and syncope. The patient's Holter study revealed sinus pauses of up to 5.3 seconds, frequent premature ventricular contractions (PVC) and some episodes of non-sustained ventricular tachycardia at 110 bpm. To avoid teratogenic radiation, dual chamber pacemaker implantation was performed guided by transthoracic echocardiography. The patient was treated with metoprolol succinate 100 mg once a day to reduce PVC and nonsustained ventricular tachycardia. During follow up, the patient reported complete resolution of syncope and dizziness. She went on to have a normal delivery without complications. PCRs for Chagas in both twins were negative.

Predictors of Right ventricular Pacing induced Left Ventricular dysfunction in Pacemaker Recipients with Preserved Ejection Fraction

Abstract Background Pacemaker (PM) has been an effective treatment in the management of patients with brady-arrhythmias. Chronic RV pacing may cause electrical and mechanical dyssynchrony which lead finally to reduced left ventricular ejection fraction (LVEF). This deterioration of LVEF has been defined as pacemaker induced cardiomyopathy (PICM). The incidence of PICM was described by many studies and ranged between 10% to 26%. The predictors for PICM have not been well studied. These studies were limited by variation in follow-up period and definition of PICM. Objective to study the incidence and predictors of PICM in patients who underwent pacemaker implantation in Ain shams University hospital. Patients and Methods This retrospective study included 160 patients who underwent single or dual chamber pacemaker implantation in Ain shams university hospital between 2010 and 2017 with the mean period 4.7±2.0 years. Implantable cardioverter defibrillator (ICD) and cardiac resynchronization therapy (CRT) patients were excluded. Individuals who had baseline transthoracic echocardiography (TTE) with normal LVEF ≥ 50% before implantation were included. Results This study included 160 patients who had single or dual chamber pacemaker implantation between 2010 and 2017. 45% were males and 55% were females, mean age was 55.5 years. It showed that the incidence of PICM is 7.5%. Wider native QRS durations, particularly >140 ms (p < 0.001), wider pQRS duration >150 ms (p < 0.001), Low normal ejection fraction <56 % preimplantation (p = 0.023) and increased LVEDD>53 mm and LVESD>38 mm (p < 0.001) are predictors for the development of PICM. Female gender was independent predictor for PICM (p = 0.058). There was no association between burden of right ventricular pacing (p = 0.782) or pacing site (p = 0.876) with the risk of development of left ventricular dysfunction. Conclusion The incidence of right ventricular pacing-induced left ventricular dysfunction is not uncommon, with an observed incidence of 7.5% in the current study. Wider native and paced QRS durations, Low normal ejection fraction (< 56 %) pre-implantation and increased LVEDD /LVESD post implantation are the most important predictors for the development of PICM. List of abbreviations PM= pacemaker, RV= Right ventricle, PICM = pacemaker induced cardiomyopathy, TTE= transthoracic echocardiography, DM= Diabetes Mellitus, HTN= Hypertension, BMI= Body Mass index, pQRSd= Paced QRS duration, SWMA= segmental wall motion abnormality, AF= Atrial fibrillation, SSS= Sick sinus syndrome, CHB= Complete heart block, AVB= Atrioventricular block, LVEF = left ventricular ejection fraction, LVEDD= Left ventricular end diastolic diameter, LVESD= Left ventricular end systolic diameter, ms= milli second.

Right ventricular perforation, pneumothorax, and a pneumatocele by a pacemaker lead: a case report

BackgroundPerforation of the right ventricle by a pacemaker lead is a rare and potentially life-threatening complication. We present a patient who developed right ventricular perforation, pneumothorax, and a cyst and underwent partial lung resection.Case presentationA 94-year-old woman was diagnosed with sick sinus syndrome and underwent a dual-chamber permanent pacemaker implantation. The next day, pacing failed and chest radiography showed that the right ventricular lead was outside the cardiac silhouette. Computed tomography revealed that the lead had perforated the right ventricular apex, causing a left-sided pneumothorax and a cystic lesion at the site of pulmonary injury by the pacemaker lead. The patient underwent lung resection and a right ventricular lead extraction. Pathological analysis revealed the cystic lesion to be an acute pneumatocele.ConclusionsPneumothorax and pneumatocele associated with right ventricular pacemaker lead perforation is extremely rare. In our case, a radical surgical intervention provided an excellent outcome.

B-PO03-009 DUAL AV NODE PATHWAYS MASQUERADING AS SYMPTOMATIC ATRIOVENTRICULAR CONDUCTION DISEASE: THE IMPORTANCE OF TREADMILL STRESS TESTING IN ESTABLISHING SYMPTOM-ARRHYTHMIA CORRELATION

Markedly prolonged AV conduction intervals (PR intervals >300ms) may represent slow pathway conduction in patients with previously undiagnosed dual AV node physiology. Treadmill stress testing is a simple and effective way to distinguish between dual AV node physiology and true AV nodal disease in patients with exertional dyspnea. 61 yo female with no significant past medical history referred to EP clinic for dual chamber pacemaker implantation. The patient presented with exercise intolerance secondary to exertional dyspnea and AV nodal conduction block thought to be contributing to her symptoms. Baseline EKG showed normal sinus rhythm and markedly prolonged PR interval at 420 ms. All other studies, including echocardiogram and pertinent bloodwork, were within normal limits. The patient agreed to proceed with exercise treadmill stress testing in an attempt to correlate her symptoms with suspected arrhythmias (AV conduction block). N/A Treadmill stress testing was performed. The patient exercised for 7 min 29 sec in a standard Bruce protocol (9.2 METS). Test was terminated secondary to fatigue and dyspnea. She exhibited a normal chronotropic response (86% MPHR). No ST segment changes consistent with ischemia were observed. Importantly, review of EKGs performed during testing revealed abrupt shortening of the PR interval during exercise. This response to exercise was consistent mechanistically with the existence of dual AV node physiology, as well as preferential fast-pathway conduction and retrograde slow-pathway block during exertion. Identification of dual-AVN physiology excluded the need for pacemaker implantation. While a markedly elevated PR interval can cause exertional dyspnea secondary to dyssynchronous atrial systole or progression to AV conduction block (Mobitz Type I/II). Establishing a symptom-arrhythmia correlation is a crucial diagnostic step. As outlined above, treadmill testing identified dual AVN physiology, and revealed benign preferential slow pathway conduction at rest as the source of the prolonged PR interval. This test excluded AV nodal disease as the source of symptoms, and ensured that the patient did not undergo unnecessary pacemaker implantation.

B-PO02-053 REDUCTION OF LEFT VENTRICULAR GLOBAL LONGITUDINAL STRAIN IN PATIENTS UNDERGOING PACEMAKER IMPLANTATION AND ITS IMPACT ON LONG TERM OUTCOMES

Chronic RV pacing >20% is associated with pacing induced cardiomyopathy. However the long term effect of RV pacing on LV global longitudinal strain (GLS) and the impact of GLS decline on clinical outcomes remains unclear. The aim of the study is to determine the impact of RV pacing on LV GLS and the association between decline of GLS and the composite endpoint of heart failure hospitalization (HFH), biventricular (BiV) upgrade or death. This is a single-center retrospective analysis of pts undergoing dual chamber pacemaker implantation between 1/1/2013 to 12/31/2018. Those with pre- and post-implantation echocardiograms suitable for strain analysis via 2D speckle tracking and with long term pacing data were included. A total of 107 patients (mean age 76 ± 11.7 yrs; 57 [53%] female) were followed for a mean duration of 23 ± 17 months. Mean baseline left ventricular ejection fraction (LVEF) was 58.5 ± 10.6% and mean GLS was -17.2 ± 3.9% prior to pacemaker implantation. Twenty-four (22%) patients had a decrease in LVEF of >10% and 43 (40%) patients had a reduction of GLS >15%. Of patients who had a reduction of GLS >15%, 67% had RV pacing burden ≥20% compared to 48% of those without a 15% reduction in GLS (p=.05). Patients with a reduction in GLS >15% had significantly higher rate of cumulative outcomes of HFH, need for BiV upgrade and death (log rank p=.001) (Figure). Significant reductions in left ventricular GLS are more commonly seen than reductions in EF after pacemaker implantation. RV pacing >20% is associated with increased risk for GLS reduction. Left ventricular GLS reduction is associated with increased risk for adverse outcomes.

Atrial Fibrillation Burden Detected by Dual-Chamber Pacemakers as a Predictor for Cardiac Outcomes: A Retrospective Single-Center Cohort Study.

Background: Atrial fibrillation (AF) might lead to adverse cardiac consequences. The association between AF burden and cardiac prognosis is unknown.Methods and Results: This retrospective cohort study enrolled 204 patients (117 males; age 74.5 ± 11.5 years) who underwent dual-chamber pacemaker implantation in our center from October 2003 to May 2017. During a median follow-up of 66.5 months, AF could be detected in 153 (75%) of the 204 pacemaker patients. Primary endpoint events (composite cardiac readmission, stroke or systemic embolism, and all-cause death) occurred in 83 cases (40.7%). In logistic regression analysis, AF detection was associated with increased risks of composite endpoints [odds ratio (OR) = 2.9, 95% confidence interval (CI): 1.3–6.2, p = 0.007], and the hazard was mainly driven by increased cardiac readmission (OR = 2.2, 95% CI: 1.1–4.7, p = 0.034). No significantly elevated risk for new-onset stroke, systemic embolism, or deaths were found in patients with AF detected than those without AF recorded. AF duration grade of more than 6 min suggested progressively increased composite endpoints (OR = 1.8, 95% CI: 1.2–2.7, p for trend = 0.005), cardiac readmission (OR = 1.8, 95% CI: 1.2–2.7, p for trend = 0.005), especially heart failure or acute coronary syndrome-associated readmission (OR = 1.8, 95% CI: 1.2–2.9, p for trend = 0.010), than those with shorter (<6 min) or no AF episodes. Kaplan–Meier analyses and Cox regression also suggested that episodes of AF more than 6 min predicted future cardiac events.Conclusions: AF detected by pacemakers were common. Higher AF burden predicted more adverse cardiac outcomes and might suggest the intervention of rhythm control in these population.

Pacemaker implantation using electroanatomical mapping system Carto 3: technical protocol, single centre experience

Abstract Funding Acknowledgements Type of funding sources: None. Background / Purpose: Three-dimensional electro-anatomical mapping systems (EAM) reduce fluoroscopy exposure during ablation procedures. The aim of this study is to evaluate the security and feasibility of performing pacemaker implantation with EAM routinely on a more regular basis (without fluoroscopy) and to draft a technical protocol to perform these implants. Methods Eight non-selected patients with pacemaker indication that had been referred to the electrophysiology unit of our institution underwent a dual chamber pacemaker implantation with EAM system Carto 3 (Biosense Webster, Irvine, CA, USA). All implants were performed by the same operator and, in all cases, the same lead model was employed. All difficulties that arose during the implantations were solved applying the actions contained in the protocol described below. First - Creation of three anatomical maps with Carto 3: venous access, right atrium and right ventricle. Annotate the end of the venous sheath. Second- For right ventricle lead positioning, connect the pacemaker lead to the Carto 3 system as an external catheter. Place the right ventricle lead, fix it and perform measurements. Third - Fuse the three maps with the "anatomical merge" tool. Fourth - Using the "design line" tool, draw a line from the tip of the lead to the end of the venous sheath following the expected trajectory of the lead in its correct position. Measure that distance. Calculate (substrate) the theoretically remaining lead. Fifth - With a ruler, measure the portion of the lead remaining out of the sheath. Sixth - Reposition the lead, if necessary. Seventh - Repeat the same procedure for the atrial lead and complete the implant procedure. Finally - Verify leads position with fluoroscopy (optional). Results : Eight patients received a dual chamber pacemaker, 75% male with a mean age 82,88 ±4,97 years. The most frequent indication was AV block (75%). The implant was performed through cephalic vein access (37,5%), subclavian vein access (50%). Mean procedure time (skin to skin) was 94 ±15 minutes. There were no complications related to the implant nor was it necessary to replace the lead. Conclusions : Pacemaker implantation with Carto 3 is a safe and reliable. The learning curve is not steep and the operator should be confident enough only after a few procedures. The protocol developed facilitates the implant procedure. Fluoroscopy timeCase12345678Fluoroscopy time (s)474786246060Dose area product (Gy*cm2)4,270,3710,0290,0630,0630,020,1230,018Abstract Figure. Carto image: dual chamber pacemaker.

The optimal cutoff of atrial high-rate episodes for neurological events in patients with dual chamber permanent pacemakers.

BackgroundPatients with atrial high‐rate episode (AHRE) are at higher risk of neurological events. This study aimed to identify the optimal cutoff threshold for AHRE duration in patients with dual chamber permanent pacemakers (PPM) without prior atrial fibrillation.MethodsWe included 355 consecutive patients receiving dual chamber pacemaker implantation. Primary outcome was composite endpoint of subsequent neurological events after various AHRE durations. AHRE was defined as >175 bpm (MEDTRONIC) or > 200 bpm (BIOTRONIK) for longer than 30 s. Cox regression analysis with time‐dependent covariates was conducted.ResultsThe mean age of included patients was 75.6 ± 11.3 years. Among 355 included patients, some had multiple AHREs; 125 patients (35.2%) developed AHRE ≥2 min, 107 (30.1%) had ≥5 min, 55 (15.5%) had ≥6 h, and 37 (10.4%) had ≥24 h. The mean follow‐up was 42.1 ± 31.2 months. During follow‐up, 19 neurological events occurred. After adjustment for CHA2DS2‐VASc score and device type, multivariate Cox regression analysis indicated AHRE ≥2 min (HR 13.605, 95% CI 3.010–61.498), and AHRE ≥5 min (HR 5.819, 95% CI 2.056–16.470) were significantly associated with neurological events. Hence, the optimal AHRE cutoff value was 2 min with the highest Youden index (sensitivity, 89.5%; specificity, 67.8%; AUC, 0.823, 95% CI, 0.763–0.884; p < 0.001).ConclusionsPatients with dual chamber PPM who develop AHRE have increased risk of neurological events. Comprehensive assessment of the risks and benefits of prescribing anticoagulants should be considered in PPM patients with AHRE ≥2 min.

Successful percutaneous extraction of a remnant floating pacemaker lead

A 72-year-old man had undergone dual-chamber pacemaker implantation for complete atrioventricular block 11 years previously, following which he actively swam and played table tennis; however, 3 years ago, he experienced...

Trends and Profile of Permanent Pacemaker Implantation in Nepal. Experience From Tertiary Cardiac Center (SGNHC) From 2001 to 2020.

Background and Aims: The number of pacemaker implantation is increasing at various centres of Nepal with increase in cardiac services. However, there are few data available regarding the pacemaker implantation in Nepal. This study intend to focus and study trends and profile of permanent pacemaker implantation (PPI) of 19 years experience at the referral tertiary cardiac center which will reflect intended objective of this study.&#x0D; Methods: This was a retrospective cross sectional study done at Shahid Gangalal National Heart Centre (SGNHC). The data of the patient who underwent PPI from 2001 November to 2020 August were reviewed. Patients data including age, sex, indication for pacing, mode of pacing, type of pacemaker implanted, implantation parameters such as lead impedence and threshold were recorded and analyzed.&#x0D; Results: A total of 3631 pacemaker implantation were performed at SGNHC from 2001 November to 2020 August. Among the total patients, 59.4% were male with mean age of 65.2±15.2 years. The most common indication was degenerative complete heart block (74.8%). Sick sinus syndrome (8.2%) was the second most common indication of pacing. The single chamber were implanted in 93.3% cases and dual chamber in 6.7% cases. VVIR was the most common mode of implantation in 93.1% cases, followed by DDDR (6.7%). AAIR (0.1%) and VDD in 0.1% cases. The total number of pacemaker implanted yearly in SGNHC has increased since the early year of implantation. During the early years most of the pacemakers were Single chamber (VVI) pacemaker and the implantation of dual chamber pacemaker increased gradually from year 2010 onwards. After the year 2010 the implantation of dual chamber pacemaker has increased significantly compared to prior to 2010 (p= 0.001). There were no gender differences in use of single chamber and dual chamber implantation during this period. (p value = 0.489). The dual chamber were implanted mostly in age group less than 65 year compared to more than 65 years (P value = 0.001). &#x0D; Conclusion: There is gradual increase in the number of pacemaker implantation yearly at SGNHC and since 2010 there is also increase in number of dual chamber pacemaker implantation though the single chamber pacemaker outnumbered the dual chamber implantation.