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BACKGROUND: The assessment of noninvasive markers of left atrial (LA) low-voltage substrate (LVS) enables the identification of atrial fibrillation (AF) patients at risk for arrhythmia recurrence after pulmonary vein isolation (PVI). METHODS: In this prospective multicenter study, 292 consecutive AF patients (72% male, 62 ± 11 years, 65% persistent AF) underwent high-density LA voltage mapping in sinus rhythm. LA-LVS (<0.5 mV) was considered as significant at 2 cm2 or above. Preprocedural clinical electrocardiogram and echocardiographic data were assessed to identify predictors of LA-LVS. The role of the identified LA-LVS markers in predicting 1-year arrhythmia freedom after PVI was assessed in 245 patients. RESULTS: Significant LA-LVS was identified in 123 (42%) patients. The amplified sinus P-wave duration (APWD) best predicted LA-LVS, with a 148-ms value providing the best-balanced sensitivity (0.81) and specificity (0.88). An APWD over 160 ms was associated with LA-LVS in 96% of patients, whereas an APWD under 145 ms in 15%. Remaining gray zones improved their accuracy by introduction of systolic pulmonary artery pressure (sPAP) of 35 mmHg or above, age, and sex. According to COX regression, the risk of arrhythmia recurrence 12 months following PVI was twofold and threefold higher in patients with APWD 145-160 and over 160 ms, compared to APWD under 145 ms. Integration of pulmonary hypertension further improved the outcome prediction in the intermediate APWD group: Patients with APWD 145-160 ms and normal sPAP had similar outcome than patients with APWD under 145 ms (hazard ratio [HR] 1.62, p = .14), whereas high sPAP implied worse outcome (HR 2.56, p < .001). CONCLUSIONS: The APWD identifies LA-LVS and risk for arrhythmia recurrence after PVI. Our prediction model becomes optimized by means of integration of the pulmonary artery pressure.
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Fibrilación Atrial , Remodelación Atrial , Ablación por Catéter , Venas Pulmonares , Fibrilación Atrial/diagnóstico por imagen , Fibrilación Atrial/cirugía , Ablación por Catéter/efectos adversos , Ecocardiografía , Electrocardiografía , Femenino , Atrios Cardíacos/diagnóstico por imagen , Humanos , Masculino , Estudios Prospectivos , Venas Pulmonares/diagnóstico por imagen , Venas Pulmonares/cirugía , Recurrencia , Resultado del TratamientoRESUMEN
Our aim was to describe the clinical profile of patients presenting sustained ventricular arrhythmias after sacubitril/valsartan (SV) initiation. All cases of sustained ventricular arrhythmias in patients receiving SV were consecutively recorded in two centers. Nineteen patients had sustained ventricular arrhythmias after SV. All were men and were previously receiving angiotensin-converting enzyme inhibitors, or angiotensin II receptor blockers before SV initiation. Fifteen patients (78.9%) had electrical stability in the previous 6 months. Nine patients (47.4%) initiated SV at the lowest available dose (24/26 mg). Globally, in all but five patients alive at discharge, SV was discontinued after the event. Six patients presented new arrhythmic events after discontinuation of SV. Two deaths and three heart transplants occurred (one due to heart failure and the other two due to persistent ventricular arrhythmias). All patients had a high arrhythmic risk, and 17 (89.5%) had an implanted cardioverter defibrillator. No specific triggers for the arrhythmic event were found. Male sex and previous episodes of ventricular arrhythmias could be associated with an increased risk of sustained ventricular tachycardia after SV initiation. Discontinuation of the drug might be an additional approach to enable a better control of ventricular arrhythmias in some patients.
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Aminobutiratos/efectos adversos , Bloqueadores del Receptor Tipo 1 de Angiotensina II/efectos adversos , Insuficiencia Cardíaca/tratamiento farmacológico , Frecuencia Cardíaca/efectos de los fármacos , Inhibidores de Proteasas/efectos adversos , Taquicardia Ventricular/inducido químicamente , Tetrazoles/efectos adversos , Anciano , Anciano de 80 o más Años , Compuestos de Bifenilo , Combinación de Medicamentos , Insuficiencia Cardíaca/complicaciones , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Neprilisina/antagonistas & inhibidores , Medición de Riesgo , Factores de Riesgo , España , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/fisiopatología , Factores de Tiempo , Resultado del Tratamiento , ValsartánRESUMEN
INTRODUCTION: Recurrences after atrial fibrillation (AF) ablation are still common. Among the reported clinical and imaging predictors of recurrences, diagnosis-to-ablation time (DAT) has been defined as a predictor of ablation outcome in single-center studies. We aimed to validate DAT in a multicenter real-life cohort. METHODS: This was a multicenter study including consecutive patients undergoing first paroxysmal and persistent AF ablation with radiofrequency or cryoballoon catheters during 2013. Cox proportional hazard regression models were performed to identify predictors of recurrence. RESULTS: In total, 309 patients were included across nine centers (71% men, 57 ± 10 years old, 46% with hypertension, and 66% with CHA2 DS2 -VASc ≤ 1). Most patients had paroxysmal AF (67%) and underwent radiofrequency ablation (68%) with a median DAT of 51 (43) months. Patients with DAT ≤ 1 year (16.6%) were less likely to have repeat procedures (4% vs 18%; P = .017). The adjusted proportional hazards Cox model identified hypertension (P = .005), heart failure (P = .011), nonparoxysmal AF (P = .038), DAT > 1 year (P = .007), and LA diameter (P = .026) as independent predictors for AF recurrence. DAT > 1 year was the only modifiable factor independently associated with recurrence (HR 4.2 [95% CI, 1.5-11.9]) CONCLUSION: Diagnosis-to-ablation time is a modifiable factor independently associated with recurrent arrhythmia and repeat ablation after first AF ablation. An early intervention strategy during the first year from AF diagnosis might improve outcomes.
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Fibrilación Atrial/cirugía , Ablación por Catéter , Criocirugía , Venas Pulmonares/cirugía , Tiempo de Tratamiento , Potenciales de Acción , Anciano , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/fisiopatología , Ablación por Catéter/efectos adversos , Criocirugía/efectos adversos , Femenino , Frecuencia Cardíaca , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Venas Pulmonares/fisiopatología , Recurrencia , Medición de Riesgo , Factores de Riesgo , España , Factores de Tiempo , Resultado del TratamientoAsunto(s)
Ablación por Catéter , Técnicas Electrofisiológicas Cardíacas , Taquicardia por Reentrada en el Nodo Atrioventricular , Humanos , Taquicardia por Reentrada en el Nodo Atrioventricular/cirugía , Taquicardia por Reentrada en el Nodo Atrioventricular/fisiopatología , Taquicardia por Reentrada en el Nodo Atrioventricular/diagnóstico , Ablación por Catéter/métodos , Nodo Atrioventricular/cirugía , Nodo Atrioventricular/fisiopatología , Resultado del Tratamiento , Potenciales de Acción , MasculinoRESUMEN
Aims: Pacing from the left ventricular (LV) endocardium might increase the likelihood of response to cardiac resynchronization therapy. However, experimental and clinical data supporting this assumption are limited and controversial. The aim of this study was to compare the acute response of biventricular pacing from the LV epicardium and endocardium in a swine non-ischaemic cardiomyopathy (NICM) model of dyssynchrony. Methods and results: A NICM was induced in six swine by 3 weeks of rapid ventricular pacing. Biventricular stimulation was performed from 16 paired locations in the LV (8 epicardial and 8 endocardial) with two different atrioventricular (80 and 110 ms) intervals and three interventricular (0, +30, -30 ms) delays. The acute response of the aortic blood flow, LV and right ventricular (RV) pressures, LVdP/dtmax and LVdP/dtmin and QRS complex width and QT duration induced by biventricular stimulation were analysed. The haemodynamic and electrical beneficial responses to either LV endocardial or epicardial biventricular pacing were similar (ΔLVdP/dtmax: +7.8 ± 2.2% ENDO vs. +7.3 ± 1.5% EPI, and ΔQRS width: -16.8 ± 1.3% ENDO vs. -17.1 ± 1.9% EPI; P = ns). Pacing from LV basal regions either from the epicardium or endocardium produced better haemodynamic responses as compared with mid or apical LV regions (P < 0.05). The LV regions producing the maximum QRS complex shortening did not correspond to those inducing the best haemodynamic responses (EPI: r2 = 0.013, P = ns; ENDO: r2 = 0.002, P = ns). Conclusion: Endocardial LV pacing induced similar haemodynamic changes than pacing from the epicardium. The response to endocardial LV pacing is region dependent as observed in epicardial pacing.
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Arritmias Cardíacas/terapia , Terapia de Resincronización Cardíaca/métodos , Cardiomiopatías/complicaciones , Endocardio/fisiopatología , Insuficiencia Cardíaca/terapia , Pericardio/fisiopatología , Función Ventricular Izquierda , Función Ventricular Derecha , Animales , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/etiología , Arritmias Cardíacas/fisiopatología , Cardiomiopatías/diagnóstico , Cardiomiopatías/fisiopatología , Modelos Animales de Enfermedad , Femenino , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/etiología , Insuficiencia Cardíaca/fisiopatología , Sus scrofa , Factores de TiempoAsunto(s)
Estimulación Cardíaca Artificial/efectos adversos , Marcapaso Artificial/efectos adversos , Taquicardia/diagnóstico por imagen , Taquicardia/etiología , Estimulación Cardíaca Artificial/tendencias , Humanos , Masculino , Persona de Mediana Edad , Marcapaso Artificial/tendencias , Taquicardia/fisiopatologíaRESUMEN
INTRODUCTION: Open-irrigated radiofrequency ablation catheters with slight differences in tip architecture are widely used, although limited comparative data are available. The purpose of this study was to compare the lesion size and potential complications produced by commercially available open-irrigated catheters in an in vitro porcine heart model. METHODS AND RESULTS: Six catheters were tested (Biosense Webster Thermocool, Boston Scientific Open irrigated, St. Jude CoolPath, St. Jude CoolPath Duo, Biosense Webster Thermocool SF, St. Jude Cool Flex) at 20 and 35 W power-control, under 2 different blood flows (0.1 and 0.5 m/s) and at 2 target durations (30 and 60 seconds). A total of 601 lesions were made in 26 in vitro preparations. The tip temperature profile showed significant differences between the catheters (P < 0.001) with the Thermocool SF registering the lowest. Only the surface diameter and the depth at maximum diameter of the lesion were influenced by the design of the ablation electrode. The lesion volume did not show significant differences between catheters for any power, application duration or blood flow condition. Char and pops occurred more often at 35 W with only slight differences between the catheters. CONCLUSIONS: Tip design of the 6 different irrigated catheters does not affect the lesion total volume, although a slight difference in lesion geometry in terms of surface diameter and depth at maximum diameter is present. The catheters show a slight different in vitro safety profile.
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Catéteres Cardíacos , Ablación por Catéter/instrumentación , Ventrículos Cardíacos/cirugía , Irrigación Terapéutica/instrumentación , Animales , Ablación por Catéter/efectos adversos , Diseño de Equipo , Ventrículos Cardíacos/patología , Técnicas In Vitro , Ensayo de Materiales , Modelos Animales , Miocardio/patología , Porcinos , Temperatura , Irrigación Terapéutica/efectos adversos , Factores de TiempoAsunto(s)
Fascículo Atrioventricular/fisiopatología , Estimulación Cardíaca Artificial/métodos , Técnicas Electrofisiológicas Cardíacas , Frecuencia Cardíaca , Taquicardia por Reentrada en el Nodo Atrioventricular/diagnóstico , Taquicardia Supraventricular/diagnóstico , Potenciales de Acción , Adulto , Fascículo Atrioventricular/cirugía , Ablación por Catéter , Femenino , Humanos , Valor Predictivo de las Pruebas , Taquicardia por Reentrada en el Nodo Atrioventricular/fisiopatología , Taquicardia por Reentrada en el Nodo Atrioventricular/cirugía , Taquicardia Supraventricular/fisiopatología , Taquicardia Supraventricular/cirugía , Factores de TiempoRESUMEN
Cardiovascular disease (CVD) is the leading cause of death worldwide affecting both sexes equally. However, in comparison to men, in women, it often is underrecognized and undertreated in both primary and secondary prevention settings. It is clear, that in the healthy population, there are profound differences both anatomically and biochemically between women and men, and this may impact how both groups present when they become ill. Moreover, some diseases affect more frequently women than men such as myocardial ischemia or infarction without obstructive coronary disease, Takotsubo syndrome, some atrial arrhythmias, or heart failure with preserved ejection fraction. Therefore, diagnostic and therapeutic strategies that have been established largely on the basis of clinical studies with a predominantly male population must be adapted before being applied to women. There is a paucity of data regarding cardiovascular disease in women. It is inadequate to only perform a subgroup analysis evaluating a specific treatment or invasive technique when women constitute fifty percent of the population. In this regard, this may affect the time of clinical diagnosis and severity assessments of some valvulopathies. In this review, we will focus on the differences in the diagnosis, management, and outcomes for women with the most frequent cardiovascular pathologies including coronary artery disease, arrhythmia, heart failure, and valvopathies. In addition, we will describe diseases that exclusively affect women that are related to pregnancy, and some of them are life-threatening. Although the lack of research on women plays a role in the poorer outcomes in women, especially in ischemic heart disease, some techniques such as transcatheter aortic valve implantation and transcatheter edge-to-edge therapy seem to have better outcomes in women.
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Enfermedades Cardiovasculares , Enfermedad de la Arteria Coronaria , Insuficiencia Cardíaca , Isquemia Miocárdica , Humanos , Masculino , Femenino , Factores de RiesgoRESUMEN
Background: Circumferential ablation around the ipsilateral pulmonary veins (PVs) is the standard strategy for atrial fibrillation ablation. The present study seeks to assess which regions of the standard ablation circumference are the main contributors to the venoatrial electrical connection. Methods: A total of 41 patients were included under a specific atrial fibrillation ablation protocol in which the anterior and posterior segments of the standard circumference, between the equatorial line of the superior and the inferior ipsilateral PVs, were ablated first. If PV isolation was not achieved, ablation was extended superiorly or inferiorly, on the basis of the earliest atrial activation recorded during pacing from inside the PV. Complete PV isolation and the length of the areas not requiring ablation (ANRA) at the time of electrical isolation were evaluated. Results: Ablation of the anterior and posterior segments of the standard circumference led to the isolation of 77% left-PV pairs and 51% right-PV pairs (p = 0,015). A superior extension was required in 23% left-PV pairs and in 46% right-PV pairs, while an inferior extension was required only in 10% left-PV pairs and in 11% right-PV pairs. PV isolation was achieved before completing the standard ablation circumference in 97% left-PV pairs and in 94% right-PV pairs, with a median ANRA of 36.9 (IQR: 30.9-42.1)â mm in the left PVs [16.0 (IQR: 12.0-19.0)â mm superior and 18.8 (IQR: 16.1-24.9)â mm inferior, p < 0.01] and 36.9 (IQR: 30.2-41.0)â mm in the right PVs [15.1 (IQR: 10.7-19.1)â mm superior and 20.6 (IQR: 16.9-23.3)â mm inferior, p < 0.01]. Conclusions: The myocardial fibers along the anterior and posterior regions of the standard ablation circumference are the main contributors to the electrical connection between the pulmonary veins and the left atrium. Ablation of these regions results in PV isolation in the majority of patients.
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Objective: To evaluate the evidence regarding the prevalence and risk of bundle branch block (BBB), atrioventricular block (AVB) and pacemaker implantation (PMI) in patients with spondyloarthritis compared to a control group without spondyloarthritis. Methods: A systematic review of the literature was performed using Pubmed (Medline), EMBASE (Elsevier) and Cochrane Library (Wiley) databases until December 2021. The prevalence and risk for AVB, BBB and PMI were analyzed. Cohort, case control and cross-sectional studies in patients ≥18 years meeting the classification criteria for spondyloarthritis were included. The Odds ratio (OR), risk ratio (RR), or Hazard ratio (HR) and prevalence difference were considered as outcomes. Data was synthesized in a previously defined extraction form which included a risk of bias assessment using the Newcastle-Ottawa Scale. Results: In total, eight out of 374 studies were included. None of the studies provided results regarding the risk of low grade AVB and BBB in SpA patients. Only indirect results comparing prevalences from low to medium quality studies were found. According to population based registries, the sex and age adjusted HR of AVB was 2.3 (95% CI 1.6-3.3) in ankylosing spondylitis, 2.9 (95% CI 1.8-4.7) in undifferentiated spondyloarthritis and 1.5 (95% CI 1.1 a 1.9) in psoriatic arthritis. The absolute risk for AVB was 0.4% (moderate to high; 95% CI 0.34%-0.69%) for AS, 0.33% (moderate to high; 95% CI 0.21%-0.53%) for uSpA and 0.34% (moderate to high; 95% CI 0.26%-0.45%) for PsA.The RR for PMI in AS patients was 1.3 (95% CI 1.16-1.46) for groups aged between 65 and 69 years, 1.33 (95% CI 1.22-1.44) for 70-75 years, 1.24 (95% CI 1.55-1.33) for 75-79 years and 1.11 (95% CI 1.06-1.17) for groups older than 80 years. The absolute risk for PMI in AS patients was 0.7% (moderate to high risk; 95% CI 0.6-0.8%) for groups aged between 65-69, 1.44% (high risk; 95% CI 1.33-1.6%) for 70-75 years, 2.09% (high risk; 95% CI 2.0-2.2%) for 75-79 years and 4.15% (high risk; 95% CI 4.0-4.3%) for groups older than 80 years. Conclusions: Very few cases of low grade AVB and BBB were observed in observational studies. No study evaluated association measures for low grade AVB and BBB but the differences of prevalence were similar in SpA and control groups even though studies lacked the power to detect statistical differences. According to population based registries there was an approximately two fold-increased risk of high grade AVB in SpA patients. RR for PMI was higher in younger age groups.
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AIMS: Despite advances in interventional treatment strategies, atrial fibrillation (AF) remains associated with significant morbidity and mortality. Fibrotic atrial myopathy (FAM) is a main factor for adverse outcomes of AF-ablation, but complex to diagnose using current methods. We aimed to derive a scoring system based entirely on easily available clinical parameters to predict FAM and ablation-success in everyday care. METHODS: In this multicenter, prospective study, a new risk stratification model termed AF-SCORE was derived in 220 patients undergoing high-density left-atrial(LA) voltage-mapping to quantify FAM. AF-SCORE was validated for FAM in an external mapping-validation cohort (n = 220) and for success following pulmonary vein isolation (PVI)-only (without adjunctive left- or right atrial ablations) in an external outcome-validation cohort (n = 518). RESULTS: FAM was rare in patients < 60 years (5.4%), but increased with ageing and affected 40.4% (59/146) of patients ≥ 60 years. Sex and AF-phenotype had additional predictive value in older patients and remained associated with FAM in multivariate models (odds ratio [OR] 6.194, p < 0.0001 for ≥ 60 years; OR 2.863, p < 0.0001 for female sex; OR 41.309, p < 0.0001 for AF-persistency). Additional clinical or diagnostic variables did not improve the model. AF-SCORE (+ 1 point for age ≥ 60 years and additional points for female sex [+ 1] and AF-persistency [+ 2]) showed good discrimination to detect FAM (c-statistic 0.792) and predicted arrhythmia-freedom following PVI (74.3%, 54.7% and 45.5% for AF-SCORE ≤ 2, 3 and 4, respectively, and hazard ratio [HR] 1.994 for AF-SCORE = 3 and HR 2.866 for AF-SCORE = 4, p < 0.001). CONCLUSIONS: Age, sex and AF-phenotype are the main determinants for the development of FAM. A low AF-SCORE ≤ 2 is found in paroxysmal AF-patients of any age and younger patients with persistent AF irrespective of sex, and associated with favorable outcomes of PVI-only. Freedom from arrhythmia remains unsatisfactory with AF-SCORE ≥ 3 as found in older patients, particularly females, with persistent AF, and future studies investigating adjunctive atrial ablations to PVI-only should focus on these groups of patients.
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Fibrilación Atrial , Cardiomiopatías , Ablación por Catéter , Venas Pulmonares , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/cirugía , Cardiomiopatías/etiología , Ablación por Catéter/efectos adversos , Ablación por Catéter/métodos , Femenino , Fibrosis , Humanos , Estudios Prospectivos , Venas Pulmonares/cirugía , Recurrencia , Resultado del TratamientoRESUMEN
Recurrence of atrial fibrillation (AF) despite successful isolation of the pulmonary veins (PVs) represents a great challenge. We present a patient with recurrent episodes of paroxysmal AF despite PV isolation in which a non-PV trigger was identified in the inferior vena cava. (Level of Difficulty: Intermediate.).
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We describe through a clinical case some of the challenges we can face when remotely monitoring a patient with two devices. The case describes a patient with two leadless pacemaker in which data transmission by remote monitoring has been achieved.
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We describe the case of a patient with a poorly tolerated ventricular tachycardia (VT) in which a substrate ablation was performed. The ablation was guided by the integrated images of the scar obtained by MRI and electro-anatomical mapping. This combined technique can make substrate ablation more accurate and may have a role in the ablation of unmappable VT.
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Mapeo del Potencial de Superficie Corporal/métodos , Ablación por Catéter , Imagen por Resonancia Magnética/métodos , Taquicardia Ventricular/patología , Taquicardia Ventricular/cirugía , Anciano de 80 o más Años , Electrocardiografía , Técnicas Electrofisiológicas Cardíacas , Humanos , Masculino , Resultado del TratamientoRESUMEN
BACKGROUND: Atrial coronary branch occlusion is a hardly recognizable clinical entity that can promote atrial fibrillation. The low diagnostic accuracy of the ECG could deal with the characteristics of the ischemia-induced changes in local atrial electrograms, but these have not been described. OBJECTIVES: We analyzed the effects of selective acute atrial branch occlusion on local myocardial structure, atrial electrograms, and surface ECG in an experimental model close to human cardiac anatomy and electrophysiology. METHODS: Six anesthetized open-chest anesthetized pigs underwent surgical occlusion of an atrial coronary branch arising from the right coronary artery during 4 h. Atrial electrograms and ECG were simultaneously recorded. One additional pig acted as sham control. In all cases, the hearts were processed for anatomopathological analysis. RESULTS: Atrial branch occlusion induced patchy atrial necrosis with sharp border zone. During the first 30 min of occlusion, atrial electrograms showed progressive R wave enlargement (1.8 ± 0.6 mV vs. 2.5 ± 1.1 mV, p < 0.01), delayed local activation times (28.5 ± 8.9 ms vs. 36.1 ± 16.4 ms, p < 0.01), ST segment elevation (-0.3 ± 0.3 mV vs. 1.0 ± 1.0 mV, p < 0.01), and presence of monophasic potentials. Atrial ST segment elevation decreased after 2 h of occlusion. The electrical border zone was â¼1 mm and expanded over time. After 2 h of occlusion, the ECG showed a decrease in P wave amplitude (from 0.09 ± 0.04 mV to 0.05 ± 0.04 mV after 165 min occlusion, p < 0.05) and duration (64.4 ± 8.0 ms vs. 80.9 ± 12.6 ms, p < 0.01). CONCLUSION: Selective atrial branch occlusion induces patchy atrial infarction and characteristic changes in atrial activation, R/S wave, and ST segment that are not discernible at the ECG. Only indirect changes in P wave amplitude and duration were appreciated in advanced stages of acute coronary occlusion.
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INTRODUCTION AND OBJECTIVES: The Micra transcatheter pacing system has shown high effectiveness and a lower complication rate than conventional transvenous pacemakers. However, the benefit of the device is unknown in the very old population (≥ 90 years). The aim of this study was to evaluate the safety and effectiveness of Micra in patients ≥ 90 years. METHODS: We present a prospective observational study with consecutive patients aged >70 years who underwent implantation of a Micra pacemaker system. Patients were divided into 2 groups: ≥ 90 and<90 years. RESULTS: The Micra system was implanted in 129 patients, of whom 41 were aged ≥ 90 years and 88<90 years. The device was successfully implanted in 40 (97.6%) patients ≥ 90 years and in 87 (98.9%) patients<90 years (P=.58). An adequate position was achieved with need for ≤ 2 repositions in 97.5% and 91.9% of patients, respectively (P=.32). Procedure time (26.1 ±11.6 vs 30.3 ±14.2minutes; P=.11) and fluoroscopy time (6.4 ±4.7 vs 7.2 ±4.9minutes; P=0.41) were similar in the 2 groups. There were 3 major complications (2.3%), all in the group aged<90 years: 1 cardiac perforation, 1 femoral hematoma, and 1 femoral pseudoaneurysm. Thirteen patients aged ≥ 90 years (31.7%) and 16 patients aged <90 years (18.2%) died during a mean follow-up of 230±233 days and 394±285 days, respectively. There were no device-related deaths. No infection, dislocation or migration of Micra were observed. The electrical performance was optimal at follow-up. CONCLUSIONS: The Micra leadless pacing system seems to be safe and effective in patients older than 90 years. It may be considered a reasonable alternative to conventional transvenous pacing in this population.