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Fetal autoimmune atrioventricular block (AVB) is a rare but potentially life-threatening condition. It results from the passage of maternal anti-SSA/Ro or Anti SSB/La auto-antibodies into the fetal circulation, leading to inflammation and fibrosis of the AV node and often to irreversible damage. Besides AVB, these antibodies can also cause cardiomyopathies, but there is no evidence linking them to tachyarrhythmias. We present the case of a patient with significant risk factors for fetal AVB: a prior history of hydrops fetalis, high anti-SSA/Ro antibody levels and hypothyroidism. In this case, the use of dexamethasone and intravenous immunoglobulin may have contributed to reversing the first-degree atrioventricular block detected at 19 weeks of gestation. Additionally, at 21 weeks, the fetus developed a tachyarrhythmia that needed treatment with flecainide. Soon after the birth, the newborn underwent ECG Holter and Wolff-Parkinson-White Syndrome (WPWS) was diagnosed. To our knowledge, the coexistence of fetal AVB and WPWS has never been described.
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Anticorpos Antinucleares , Bloqueio Atrioventricular , Taquicardia , Síndrome de Wolff-Parkinson-White , Humanos , Feminino , Gravidez , Anticorpos Antinucleares/sangue , Anticorpos Antinucleares/imunologia , Síndrome de Wolff-Parkinson-White/diagnóstico , Síndrome de Wolff-Parkinson-White/imunologia , Taquicardia/diagnóstico , Taquicardia/etiologia , Bloqueio Atrioventricular/diagnóstico , Bloqueio Atrioventricular/imunologia , Bloqueio Atrioventricular/etiologia , Adulto , Recém-Nascido , Doenças Fetais/diagnóstico , Doenças Fetais/imunologia , Imunoglobulinas Intravenosas/uso terapêuticoRESUMO
In the present case report, we describe the clinical course and postmortem findings of a 12-year-old Labrador retriever dog with a third-degree atrio-ventricular block that developed a chronic cough, and later dyspnea and weakness as a result of massive pulmonary thromboembolism 3 years after implantation of a transvenous permanent pacemaker. A large soft tissue mass was seen in the right ventricular chamber around the pacing lead with echocardiography. Initially, this was thought to be caused by mural bacterial endocarditis based on hyperthermia, severe leukocytosis and the appearance of runs of ventricular tachycardia, the latter suggesting myocardial damage. While blood culture results were pending, antibiotics were administered without a positive effect. Due to clinical deterioration, the owner elected for euthanasia and a post-mortem examination confirmed a right ventricular thrombus and surrounding myocarditis, without signs of bacterial infection, and a massive pulmonary thromboembolism. We conclude that pulmonary thromboembolism should be considered in dogs with a cough that have an endocardial pacing lead implanted. Serial screening for proteinuria before and after implantation of an endocardial pacing lead would allow timely initiation of prophylactic antiplatelet therapy. Local myocarditis can develop secondary to an intracavitary thrombus, which can subsequently lead to runs of ventricular tachycardia.
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Vasospastic angina is a clinical condition characterized by coronary artery spasm in angiographically normal coronary arteries. Vasospastic angina can often lead to ventricular arrhythmias, sudden cardiac death, or life-threatening bradyarrhythmias, such as high-degree atrioventricular block or asystole. We present the unusual case of a woman with depressive syndrome who underwent emergency surgery for hemostasis of a neck lesion that caused hemorrhagic shock after a suicide attempt. During surgery, the electrocardiogram revealed inferior and posterior ST-segment elevation, total atrioventricular block and torsades de pointes; the patient also suffered 4 minutes of cardiac arrest. A temporary pacemaker was placed. Coronary angiography showed right coronary artery vasospasm. Following a second similar episode after tracheostomy, a permanent pacemaker was implanted. The indication for definitive electrostimulation in such a context and the stimulation mechanisms of the carotid sinus underlying vasospasm constitute the interesting points of this clinical case. LEARNING OBJECTIVE: The indication for definitive electrostimulation in a context of recurrent episodes of high-degree atrioventricular block during vasospastic angina and the stimulation mechanisms of the carotid sinus underlying vasospasm constitute the interesting points of this clinical case.
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Adenosine is a widely used pharmacologic agent in the field of cardiology, predominantly for the termination of supraventricular tachycardias and diagnostic purposes. Most of the side effects are short-lasting due to its very short half-life. Fatal complications of adenosine are rare but can include ventricular fibrillation, ventricular tachycardia, and asystole. Proper medical supervision and monitoring are crucial to minimize risks. We report a unique case of a second-degree type 2 sinoatrial node exit block following intravenous adenosine administration in a 25-year-old male presenting with palpitations.
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We report a long QT syndrome 15 whose diagnosis was suspected during foetal life and confirmed at birth and was associated with congenital heart disease. Genetic testing revealed a rare mutation associated with the CALM2 gene. At 23 weeks of gestation, severe foetal sinus bradycardia (â¼100 bpm) was detected. In the third trimester, the foetus developed severe right ventricular hypertrophy. At birth, the electrocardiogram showed a long QT interval of 640 ms, and after 1 hour, the newborn showed functional 2:1 atrioventricular block at ventricular rate of 50 bpm. After further pharmacological therapies, epicardial wires were surgically implanted for transient pacing in VVI mode at 90 bpm. Echocardiogram showed aneurysmatic left atrial appendage, dilated right segments, hypertrophied right ventricle, ostium secundum type atrial septal defect, and muscular ventricular septal defect. At two weeks of postpartum, a permanent dual-chamber pacemaker was implanted in the DDD mode and the patient was discharged with a prescription of beta-blockers and calcium therapy.
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Cardiac sarcoidosis (CS) is a rare multisystem disorder characterized by granulomatous infiltration of the myocardium, which can lead to significant morbidity and mortality. Its clinical manifestations range from asymptomatic conduction abnormalities to severe heart failure (HF) and sudden cardiac death. This comprehensive review aims to provide an overview of the diagnosis, clinical features, and current medical management strategies for CS. Additionally, the role of implantable cardioverter-defibrillators (ICDs) and the potential use of positron emission tomography in guiding management decisions are explored. A comprehensive understanding of the medical management of CS is essential for improving patient outcomes and guiding future research endeavors.
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Our case report highlights the importance of understanding various mechanisms of an atrioventricular block (AVB) and recognizing potential iatrogenic culprits. Despite the prevalent use of second-generation antipsychotics and the growing popularity of long-acting formulations, it is not routinely recognized as a cause for AVB. Second-generation antipsychotics such as risperidone have a dose-dependent pro-arrhythmic effect and are known to cause first-degree AVB. Our case presents an opportunity to recognize an unappreciated cause for AVB and switch to safer alternatives. In the era of long-acting injectables, it is important to monitor for these effects prior to escalating doses and risking high-degree AVB.
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Though permanent pacemaker implantation is the only effective therapy for certain bradyarrhythmias in dogs, it is not without risks. Bacterial infection of the device is one of the most common complications. Human guidelines recommend besides systemic antibiotics, surgical explantation of the pacing lead and pulse generator in case of device-infection. This report describes a 13.5-year-old dog that received a transvenous endocardial permanent pacemaker because of syncopal episodes resulting from paroxysmal third-degree atrio-ventricular block. Five days after an uneventful surgery, a painful swelling appeared around the subcutaneous part of the lead where this was inserted into the jugular vein. A 4-week course of amoxicillin and clavulanic acid combined with enrofloxacin failed to clear the infection on long-term. Ultrasound-guided puncture of the abscess was performed to gain a sample for bacterial culture and antibiogram. Oral clindamycin of 4 weeks' duration successfully resolved the infection with Staphylococcus aureus without having to explant the device. Repeated ultrasonographic examinations and fine-needle aspiration biopsies were used to evaluate for persistent local inflammation, guiding the length of the antibiotic therapy. Though the described approach has traditionally been ill-advised because of the risk of introducing bacteria and damaging the pacemaker lead, it was successful in our case.
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In early 2020 Food and Drug Administration (FDA) approved Micra AV - a new type of leadless pacemaker with atrioventricular synchrony, to treat patients with atrio-ventricular (AV) blocks. We describe one of the first in Poland case of a patient who was implanted with Micra AV pacemaker. CASE REPORT: A 38-year-old female patient was admitted to the clinic due to the 29-seconds event of a complete AV block without an escape rhythm and was implanted with a dual chamber pacemaker without any complications. After several months she was admitted again with suspicion of ventricular perforation by the pacemaker electrode and underwent a replacement procedure of both pacemaker's leads. Nevertheless, one week later the patient developed a fever with significantly elevated inflammatory markers. The blood cultures were negative but in the transesophageal echocardiography features of cardiac device-related infective endocarditis were observed. Empirical antibiotic therapy was administered, and the device was removed. The Heart Team qualified the patient for the implantation of a MicraTM AV leadless pacemaker. The procedure was performed without any complications and the device was implanted to the right ventricle. All parameters were correct, and the patient was discharged. CONCLUSIONS: Micra AV may be a feasible and safe option for young patients with paroxysmal AV block after device-related complications.
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Bloqueio Atrioventricular , Endocardite , Marca-Passo Artificial , Feminino , Humanos , Adulto , Bloqueio Atrioventricular/terapia , Bloqueio Atrioventricular/etiologia , Marca-Passo Artificial/efeitos adversos , Ventrículos do Coração , Endocardite/complicações , AntibacterianosRESUMO
Background: Currently, the leadless pacemaker indications are limited to few and highly selected cases. Case summary: We describe the first reported case of an atrioventricular Micra™ leadless pacemaker implantation complicated by tricuspid posterior leaflet flail with severe regurgitation in a 29-year-old man affected by asymptomatic and progressive high degree atrio-ventricular block. The patient was then treated with endoscopic tricuspid valve repair, leadless pacemaker removal and implantation of an epicardial pacemaker. Discussion: Leadless pacemaker complications are multiple, hence it is essential to ensure a safe procedure, especially in the younger patients. We thought that the application of a transesophageal echocardiography guidance might mitigate the risk of major complications.
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Progressive cardiac conduction disease (PCCD) is a relatively common condition in young and elderly populations, related to rare mutations in several genes, including SCN5A, SCN1B, LMNA and GJA5, TRPM4. Familial cases have also been reported. We describe a family with a large number of individuals necessitating pacemaker implantation, likely due to varying degrees of PCCD. The proband is a 47-year-old-patient, whose younger brother died at 25 years of unexplained sudden cardiac death. Three paternal uncles needed a pacemaker (PM) implantation between 40 and 65 years for unspecified causes. At the age of 42, he was implanted with a PM for two episodes of syncope and the presence of complete atrioventricular block (AVB). NGS analysis revealed the missense variation c. 2351G>A, p.Gly844Asp in the exon 17 of the TRPM4 gene. This gene encodes the TRPM4 channel, a calcium-activated nonselective cation channel of the transient receptor potential melastatin (TRPM) ion channel family. Variations in TRPM4 have been shown to cause an increase in cell surface current density, which results in a gain of gene function. Our report broadens and supports the causative role of TRPM4 gene mutations in PCCD. Genetic screening and identification of the causal mutation are critical for risk stratification and family counselling.
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Bloqueio Atrioventricular , Canais de Cátion TRPM , Idoso , Bloqueio Atrioventricular/genética , Bloqueio Atrioventricular/metabolismo , Morte Súbita Cardíaca , Coração , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Canais de Cátion TRPM/genética , Canais de Cátion TRPM/metabolismoRESUMO
OBJECTIVES: Complications like complete atrioventricular block (CAVB) and paravalvular leakage (PVL) following rapid deployment aortic valve (AV) replacement (RDAVR) remain unresolved. Selecting an optimal size of the valve might be important to minimize the incidence of these complications. We sought to determine the impact of prosthesis size relative to the anatomic profile of the AV on the occurrence of CAVB or PVL after RDAVR. METHODS: Preoperative computed tomographic (CT) images were evaluated in patients receiving RDAVR (INTUITY ELITE) between February 2016 and December 2019. The occurrence of CAVB requiring permanent pacemaker implantation and PVL (≥ mild) was evaluated. The relative size of implants against the cross-sectional dimensions of recipients' AV annulus and left ventricular outflow tract (LVOT) were calculated. RESULTS: Among 187 eligible patients, CAVB and PVL (≥ mild) occurred in 12 (6.4%) and 11 patients (5.9%), respectively. CAVB was associated with oversized RDAVR (RDAVR frame width minus average diameter of LVOT calculated from the cross-sectional area [ΔLVOTarea]: odds ratio, 2.05; 95% confidence interval, 1.28-3.30): this was with an area under the curve of 0.78 (P = 0.005). The projected probability of CAVB was <3% when the ΔLVOTarea was <1.3. In contrast, PVL was associated with under-sized RDAVR (RDAVR size divided by the longest diameter of AV annulus [index Annlong]: odds ratio, 0.64; 95% confidence interval, 0.51-0.79): This was with an area under curve of 0.94 (P < 0.001). CONCLUSIONS: CT parameters of the AV annulus and LVOT are highly reliable in the prediction of CAVB or PVL after RDAVR. Our data might justify CT-based sizing of prosthesis for RDAVR.
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Estenose da Valva Aórtica , Implante de Prótese de Valva Cardíaca , Próteses Valvulares Cardíacas , Substituição da Valva Aórtica Transcateter , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/cirurgia , Próteses Valvulares Cardíacas/efeitos adversos , Implante de Prótese de Valva Cardíaca/efeitos adversos , Implante de Prótese de Valva Cardíaca/métodos , Humanos , Desenho de Prótese , Tomografia Computadorizada por Raios X , Substituição da Valva Aórtica Transcateter/efeitos adversos , Resultado do TratamentoRESUMO
BACKGROUND: The optimal right ventricular (RV) pacing site during pacemaker implantation is still unclear due to left ventricular (LV) dyssynchrony by traditional RV pacing. His-bundle (HIS) pacing has achieved narrow QRS and maintained LV synchrony but high failure rate. RV septal pacing occasionally has QRS waveform with wide and narrow component in the early and late phase, respectively, and maintains LV synchrony, reflecting the normal conduction system. We aimed to define this QRS waveform as retrograde penetration pacing into the conduction system (RPP-CS) and compared its effect on LV synchrony as an alternative approach of HIS pacing. METHODS AND RESULTS: We enrolled 42 patients with atrio ventricular block (AVB) or bradycardia atrial fibrillation (AF) requiring pacemaker implantation (RPP-CS, n = 27; no RPP-CS, n = 15). Baseline characteristics were similar between the groups. RPP-CS was observed in 96% and 26% of the RV septum and apex area, respectively. RPP-CS had a significantly shorter QRS width (p < 0.001). The frequency of maintaining LV synchrony was significantly higher in RPP-CS (67% vs. 20%, p = 0.003). The QRS interval's optimal cut-off value during RPP-CS was 132 ms for prediction of LV synchrony (sensitivity 83%, specificity 89%, positive predictive value 94%, and negative predictive value 73%). During RPP-CS, shorter QRS intervals (QRS ≤ 132 ms) had better postoperative LV ejection fraction than longer intervals (p < 0.001). CONCLUSIONS: RPP-CS, especially with short QRS intervals (≤132 ms), had a high frequency of LV synchrony, maintained postoperative cardiac function, and may be an adequate first-line RV pacing site strategy for AVB or bradycardia AF as an alternative approach of HIS pacing.
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Estimulação Cardíaca Artificial , Marca-Passo Artificial , Estimulação Cardíaca Artificial/métodos , Eletrocardiografia , Sistema de Condução Cardíaco , Humanos , Função Ventricular EsquerdaRESUMO
Lyme disease caused by Borrelia burgdorferi is a multisystem disease and can lead to Lyme carditis. The most common presentation of Lyme carditis is conduction system disturbances such as atrioventricular (AV) block. A 72-year-old male with a past medical history of gastroesophageal reflux disease (GERD) and prostate cancer presented with chest tightness, lightheadedness, and presyncope. During hospitalization, he developed bradycardia with heart rates ranging between 30 and 40 beats per minute and Wenckebach heart block. Lyme serology was consistent with a recent Lyme infection. He was treated with antibiotics and was eventually discharged home without requiring pacemaker implantation.
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Leadless pacemaker is indicated in patients with symptomatic bradycardia as an alternative therapy when transvenous pacemaker implantation is considered difficult or at high risk. The experience of implanting leadless pacemaker in patients with dextrocardia and situs inversus is limited. A 94-year-old male was transferred to our hospital due to advanced atrio-ventricular block with episode of syncope. Chest radiograph and computed tomography revealed dextrocardia with situs inversus. Emergency cardiac catheterization was performed and a temporary pacemaker was inserted, but the patient removed it due to delirium. So, a leadless pacemaker was implanted to him. Shorter time of bed-rest after the implantation and shorter hospital stay would be beneficial of implanting a leadless pacemaker. Precise anatomical evaluation would be important to perform implantation efficiently and safely.
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Several cardiovascular diseases and arrhythmic disorders have been described in COVID-19 era as likely related to SARS-CoV-2 infection. The prognostic relevance of bradyarrhythmias during the infection has not been yet described and no data are available about long-term heart conduction disorders. A review of literature concerning the association between hypokinetic arrhythmias and COVID-19 from January 2020 to February 2021 was performed. The key-words used for the research were: "sinus node disfunction," "sick sinus syndrome (SSS)," "sino-atrial block," "atrio-ventricular block (AVB)," "bradyarrhythmias," and "COVID-19â³ or "SARS-CoV-2.â³ Excluding "relative bradycardia," a total of 38 cases of bradyarrhythmia related to SARS-CoV-2 infection have been described, even in very young people, requiring in many cases a definitive pacemaker implantation. Furthermore, we report a case of non-hospitalized 47-years old man with a SSS developed as a consequence of mild SARS-CoV-2 infection. While in all described cases heart conduction disorders were found at presentation of the infection or during hospitalization for COVID-19, in our case the diagnosis of SSS was made after the resolution of the infection. Although rarely, heart conduction disorders may occur during COVID-19 and the present case highlights that a cardiological follow up may be desirable even after the resolution of infection, especially in the presence of symptoms suggesting a possible heart involvement.
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Bradicardia/virologia , COVID-19/complicações , Síndrome do Nó Sinusal/virologia , Bradicardia/fisiopatologia , Bradicardia/terapia , Eletrocardiografia , Humanos , Masculino , Pessoa de Meia-Idade , Marca-Passo Artificial , Prognóstico , SARS-CoV-2 , Síndrome do Nó Sinusal/fisiopatologia , Síndrome do Nó Sinusal/terapiaRESUMO
Background. High-grade AV block (HGAVB) is a life-threatening condition. Acute kidney injury (AKI) which is usually caused by renal hypo-perfusion is associated with adverse outcomes. We aimed to investigate the association between AKI and HGAVB. Methods. This is a retrospective cohort comparing the incidence of AKI among patients with HGAVB requiring pacemaker implantation compared with propensity score matched controls. Primary outcome was the incidence of AKI at admission. Secondary outcomes were change in creatinine levels, AKI during stay, recovery from AKI, mortality and major adverse kidney events (MAKE). Results. In total, 80 HGAVB patients were compared to 400 controls. HGAVB patients had a higher proportion of admission AKI compared to controls (36.2% versus 21.1%, RR = 1.71 [1.21-2.41], p = 0.004). Creatinine changes from baseline to admission and to maximum during hospitalization, were also higher in HGAVB (p = 0.042 and p = 0.033). Recovery from AKI was more frequent among HGAVB patients (55.2% vs. 25.9%, RR = 2.13 [1.31-3.47], p = 0.004) with hospitalization time, MAKE and crude mortality similar (p > 0.158). Conclusions. AKI occurs in about one third of patients admitted with HGAVB, more frequent compared to controls. Patients with AKI accompanying HGAVB were likelier to recover from AKI. Further studies to explore this relationship could aid in clinical decision making for HGAVB patients.
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BACKGROUND: Coronary artery spasm has rarely been reported in pediatric patients. Previous studies have reported comorbidities and risk factors for coronary artery spasms. We present the case of a complete atrio-ventricular (AV) block that occurred in the absence of other risk factors immediately after direct laryngoscopy. CASE PRESENTATION: A 2-year-old girl developed severe coronary artery spasm after direct laryngoscopy for elective laryngeal papillomatosis resection. Immediately after the initiation of laryngoscopy, complete AV block and ST elevation on lead II of the electrocardiogram were observed. These findings indicated that the complete AV block was caused by a right coronary artery spasm. CONCLUSION: Coronary artery spasm resulting in lethal arrhythmia rarely occurs in healthy pediatric patients. To the best of our knowledge, this is the first pediatric case of a severe coronary artery spasm resulting in a complete AV block due to direct laryngoscopy in a healthy patient.
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OBJECTIVES: The aim of the study was to compare the clinical outcomes [atrial fibrillation (AF), atrio-ventricular (AV) block, device sepsis and lead revision] of patients with sinus node dysfunction (SND) between atrial-pacing atrial-sensing inhibited-response rate-adaptive (AAIR) versus dual-chamber rate-adaptive (DDDR) pacing. The choice of AAIR pacing versus DDDR pacing was determined by AV nodal functional testing at implant. METHODS: We conducted a retrospective review of consecutive patients who underwent AAIR and DDDR pacing over a 10-year period. RESULTS: One hundred and sixteen patients required pacing for symptomatic SND. Fifty-four (46.6%) patients received AAIR pacemakers and 62 (53.4%) received DDDR pacemakers based on AV nodal functional testing at implant. Patients who had AV Wenkebach with atrial pacing at 120 beats per minute received DDDR pacing. Overall the mean age of patients with SND was 65 years and 66.4% were females, 30% were diabetics and 71% were hypertensives. Pre-syncope/syncope (84%) and dizziness (69%) were the most common symptoms. Sinus pauses and sinus bradycardia were the most common ECG manifestations. Over a median follow up of five (IQR: 2-11) years, four patients (7.4%) developed AF in the AAIR group compared to three (4.8%) in the DDDR group (p = 0.70). AV block occurred in one patient in the AAIR group, who required an upgrade to a DDDR pacemaker. There was no difference in device sepsis or need for lead revision between the two groups. CONCLUSIONS: We found that AV nodal functional testing with atrial pacing at the time of pacemaker implantation was a useful tool to help guide the implanter between AAIR or DDDR pacing. Patients who underwent AAIR pacing had a low risk of AF, AV block or lead revision. In resource-limited settings, AAIR pacing guided by AV nodal functional testing should be considered as an alternative to DDDR pacing.
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Fibrilação Atrial/terapia , Bloqueio Atrioventricular/terapia , Estimulação Cardíaca Artificial/métodos , Marca-Passo Artificial , Sepse , Síndrome do Nó Sinusal/terapia , Idoso , Fibrilação Atrial/diagnóstico , Feminino , Seguimentos , Humanos , Estudos Retrospectivos , Síndrome do Nó Sinusal/diagnóstico , SíncopeRESUMO
BACKGROUND: VDD pacemakers are regarded as a second choice in patients with atrio-ventricular blocks mainly due to the potential failure of atrial sensing, leading to a loss of atrio-ventricular synchrony. This single-centre study aimed to evaluate the prevalence of loss of atrial sensing and its potential determinants in patients with VDD pacemakers. METHOD: 142 patients with an implanted VDD device underwent long-term follow-up with clinical evaluation, electrocardiogram, device interrogation and echocardiogram. RESULTS: Over a long follow-up period [median 110 (68-156) months], 17 patients (12%) in sinus rhythm presented loss of atrial sensing. This was most often intermittent, but three patients required a permanent switch to VVI mode. ECG showed higher prevalence of interatrial blocks (50% vs 26.6%, p = 0.057) and longer P wave duration (116 ± 19 vs 105 ± 15 ms, p = 0.019) in patients with loss of atrial sensing. Echocardiography revealed larger left atrial (LA) volumes (p < 0.05) in patients with loss of atrial sensing, and lower LA ejection fraction (0.40 vs 0.47, p = 0.0037) and expansion index (0.63 ± 0.26 vs 0.90 ± 0.31, p = 0.003). P wave duration on ECG proved to be independently associated with loss of atrial sensing on multivariable analysis (OR 1.062, 95% CI 1.015-1.110; p = 0.008). The prevalence of atrial fibrillation and subsequent switch to VVI mode was high (16%). CONCLUSIONS: In the long-term follow-up, the loss of atrial sensing is present in 12% of patients with implanted VDD pacemakers. ECG and echocardiographic parameters may serve as screening tools for the detection of atrial myopathy which is associated with the loss of atrial sensing.