Incidence, predictors, and prognostic significance of impaired functional status early after transcatheter aortic valve replacement.

INTRODUCTION AND OBJECTIVES: There are scarce data on the factors associated with impaired functional status after transcatheter aortic valve replacement (TAVR) and its clinical impact. This study aimed to determine the incidence, predictors, and prognostic implications of impaired functional class (NYHA class III-IV) following TAVR. METHODS: This multicenter study included 3462 transarterial TAVR patients receiving newer generation devices. The patients were compared according to their NYHA class at 1 month of follow-up (NYHA I-II vs NYHA III-IV). A multivariate logistic regression was performed to identify the predictors of 30-day NYHA class III-IV. Patient survival was compared with the Kaplan-Meier method and factors associated with decreased survival were identified with Cox regression analysis. RESULTS: The mean age of the study population was 80.3±7.3 years, with 47% of women, and a median Society of Thoracic Surgeons score of 3.8% [IQR, 2.5-5.8]. A total of 208 patients (6%) were in NYHA class III-IV 1 month after TAVR. Predictors of 30-day NYHA class III-IV were baseline NYHA class III-IV (OR, 1.76; 95%CI, 1.08-2.89; P=.02), chronic pulmonary obstructive disease (OR, 1.80; 95%CI, 1.13-2.83; P=.01), and post-TAVR severe mitral regurgitation (OR, 2.00; 95%CI, 1.21-3.31; P<.01). Patients in NYHA class III-IV 1 month after TAVR were at higher risk of death (HR, 3.68; 95%CI, 2.39-5.70; P<.01) and heart failure-related hospitalization (HR, 6.00; 95%CI, 3.76-9.60; P<.01) at 1-year follow-up. CONCLUSIONS: Up to 6% of contemporary TAVR patients exhibited an impaired functional status following TAVR. Worse baseline NYHA class, chronic pulmonary obstructive disease, and severe mitral regurgitation predicted 30-day NYHA class III/IV, and this determined a higher risk of mortality and heart failure hospitalization at 1-year follow-up. Further studies on the prevention and treatment optimization of patients with impaired functional status after TAVR are needed.

Impact of a successful percutaneous mitral paravalvular leak closure on long-term major clinical outcomes.

BACKGROUND: Percutaneous mitral paravalvular leak (PVL) closure techniques are an effective and safe alternative to surgical treatment, but data regarding long-term outcomes are scarce. We aim to describe the impact of successful percutaneous mitral PVL closure on long-term outcomes. METHODS: All consecutive patients in whom a first-attempt percutaneous mitral PVL closure was performed in a single tertiary center between January 2010 and October 2021 were included. Clinical variables, procedural details and procedural success were collected. Patients were classified based on procedural success, defined as no more than mild residual leak. All-cause mortality was the primary endpoint. Cardiovascular death and heart failure hospitalizations (HFH) were key secondary endpoints. RESULTS: Ninety patients (median age 72.5 years [66.0-78.4]; median Euroscore-II 8.2 [5.3-12.46]) were included. Although reduction of at least one degree in PVL severity was achieved in 82 (91.1%), procedural success was achieved in 47 (52.2%). Chronic kidney disease, previous surgery for PVL, and the presence of multiple jets, were independently associated with procedural failure. After a median follow-up of 3.2 (1.2-5.2) years, mortality rate was higher in the procedural failure group (27.3 per 100 patients-years) compared to the group with successful closure (8.2 per 100 patient-years). Procedural failure was associated with all-cause death (adjusted hazard ratio [aHR]:2.59; 95%CI:1.41-4.78), cardiovascular death (aHR:3.53, 95%CI:1.67-7.49) and HFH (aHR:3.27, 95%CI:1.72-6.20). CONCLUSIONS: A successful reduction in PVL to mild or absent is associated with improved rates of all-cause death, cardiovascular death and HFH.

Cardiac Death After Transcatheter Aortic Valve Replacement With Contemporary Devices.

BACKGROUND: The burden of cardiac death after transcatheter aortic valve replacement (TAVR), particularly from advanced heart failure (HF) and sudden cardiac death (SCD), remains largely unknown. OBJECTIVES: This study sought to evaluate the incidence and predictors of SCD and HF-related death in TAVR recipients treated with newer-generation devices. METHODS: This study included a total of 5,421 consecutive patients who underwent TAVR with newer-generation devices using balloon (75.7%) or self-expandable (24.3%) valves. RESULTS: After a median follow-up of 2 (IQR: 1-3) years, 976 (18.0%) patients had died, 50.8% from cardiovascular causes. Advanced HF and SCD accounted for 11.6% and 7.5% of deaths, respectively. Independent predictors of HF-related death were atrial fibrillation (HR: 2.17; 95% CI: 1.47-3.22; P < 0.001), prior pacemaker (HR: 1.79; 95% CI: 1.10-2.92; P = 0.01), reduced left ventricular ejection fraction (HR: 1.08 per 5% decrease; 95% CI: 1.01-1.14; P = 0.02), transthoracic approach (HR: 2.50; 95% CI: 1.37-4.55; P = 0.003), and new-onset persistent left bundle branch block (HR: 1.85; 95% CI: 1.14-3.02; P = 0.01). Two baseline characteristics (diabetes, HR: 1.81; 95% CI: 1.13-2.89; P = 0.01; and chronic kidney disease, HR: 1.72; 95% CI: 1.02-2.90; P = 0.04) and 3 procedural findings (valve in valve, HR: 2.17; 95% CI: 1.01-4.64; P = 0.04; transarterial nontransfemoral approach, HR: 2.23; 95% CI: 1.23-4.48; P = 0.01; and periprocedural ventricular arrhythmia, HR: 7.19; 95% CI: 2.61-19.76; P < 0.001) were associated with an increased risk of SCD after TAVR. CONCLUSIONS: Advanced HF and SCD accounted for a fifth of deaths after TAVR in contemporary practice. Potentially treatable factors leading to increased risk of HF deaths and SCD were identified, such as arrhythmia/dyssynchrony factors for HF and valve-in-valve TAVR or periprocedural ventricular arrhythmias for SCD.

Optimal opportunistic screening of atrial fibrillation using pulse palpation in cardiology outpatient clinics: Who and how.

BACKGROUND: Atrial fibrillation (AF) remain a prevalent undiagnosed condition frequently encountered in primary care. OBJECTIVE: We aimed to find the parameters that optimize the diagnostic accuracy of pulse palpation to detect AF. We also aimed to create a simple algorithm for selecting which individuals would benefit from pulse palpation and, if positive, receive an ECG to detect AF. METHODS: Nurses from four Cardiology outpatient clinics palpated 7,844 pulses according to a randomized list of arterial territories and durations of measure and immediately followed by a 12-lead ECG, which we used as the reference standard. We calculated the sensitivity and specificity of the palpation parameters. We also assessed whether diagnostic accuracy depended on the nurse's experience or on a list of clinical factors of the patients. With this information, we estimated the positive predictive values and false omission rates according to very few clinical factors readily available in primary care (age, sex, and diagnosis of heart failure) and used them to create the algorithm. RESULTS: The parameters associated with the highest diagnostic accuracy were palpation of the radial artery and classifying as irregular those palpations in which the nurse was uncertain about pulse regularity or unable to palpate pulse (sensitivity = 79%; specificity = 86%). Specificity decreased with age. Neither the nurse's experience nor any investigated clinical factor influenced diagnostic accuracy. We provide the algorithm to select the ≥40 years old individuals that would benefit from a pulse palpation screening: a) do nothing in <60 years old individuals without heart failure; b) do ECG in ≥70 years old individuals with heart failure; c) do radial pulse palpation in the remaining individuals and do ECG if the pulse is irregular or you are uncertain about its regularity or unable to palpate it. CONCLUSIONS: Opportunistic screening for AF using optimal pulse palpation in candidate individuals according to a simple algorithm may have high effectiveness in detecting AF in primary care.

Coste-efectividad del desfibrilador automático implantable para la prevención primaria de la muerte súbita cardiaca / Cost-effectiveness of implantable cardioverter-defibrillators for primary prevention of sudden cardiac death

Introducción y objetivos: El desfibrilador automático implantable (DAI) es una alternativa coste-efectiva para la prevención secundaria de la muerte súbita cardiaca, pero sigue habiendo dudas sobre su eficiencia en prevención primaria, sobre todo en pacientes con cardiopatía no isquémica.Métodos: Análisis de coste-utilidad del DAI más tratamiento médico convencional frente a tratamiento médico convencional para la prevención primaria de arritmias cardiacas desde la perspectiva del Sistema Nacional de Salud. Se simuló el curso de la enfermedad mediante modelos de Markov en pacientes con y sin cardiopatía isquémica. Los parámetros del modelo se basaron en los resultados obtenidos mediante metanálisis de los ensayos clínicos publicados entre 1996 y 2018 en los que se comparaba el DAI con el tratamiento médico convencional, los resultados de seguridad del ensayo DANISH y el análisis de la práctica clínica habitual en un hospital terciario.Resultados: Se estimó un beneficio del DAI sobre la muerte por cualquier causa con HR = 0,70 (IC95%, 0,58-0,85) en cardiopatía isquémica y HR = 0,79 (IC95%, 0,66-0,96) en no isquémica. La razón de coste-efectividad incremental estimada mediante análisis probabilístico fue de 19.171 euros/año de vida ajustado por calidad (AVAC) en pacientes con cardiopatía isquémica, 31.084 euros/AVAC en pacientes con miocardiopatía dilatada no isquémica y 23.230 euros/AVAC en los menores de 68 años.Conclusiones: La eficiencia del DAI monocameral ha mejorado en la última década y este resulta coste-efectivo para los pacientes con disfunción ventricular izquierda de origen isquémico o no isquémico menores de 68 años considerando una disposición a pagar 25.000 euros/AVAC. En pacientes no isquémicos mayores, la razón de coste-efectividad incremental estimada se sitúa alrededor de los 30.000 euros/AVAC (AU)

Introduction and objective: Implantable cardioverter-defibrillators (ICD) are a cost-effective alternative for secondary prevention of sudden cardiac death, but their efficiency in primary prevention, especially among patients with nonischemic heart disease, is still uncertain.Methods: We performed a cost-effectiveness analysis of ICD plus conventional medical treatment (CMT) vs CMT for primary prevention of cardiac arrhythmias from the perspective of the national health service. We simulated the course of the disease by using Markov models in patients with ischemic and nonischemic heart disease. The parameters of the model were based on the results obtained from a meta-analysis of clinical trials published between 1996 and 2018 comparing ICD plus CMT vs CMT, the safety results of the DANISH trial, and analysis of real-world clinical practice in a tertiary hospital.Results: We estimated that ICD reduced the likelihood of all-cause death in patients with ischemic heart disease (HR, 0.70; 95%CI, 0.58-0.85) and in those with nonischemic heart disease (HR, 0.79; 95%CI, 0.66–0.96). The incremental cost-effectiveness ratio (ICER) estimated with probabilistic analysis was €19 171/quality adjusted life year (QALY) in patients with ischemic heart disease and €31 084/QALY in those with nonischemic dilated myocardiopathy overall and €23 230/QALY in patients younger than 68 years.Conclusions: The efficiency of single-lead ICD systems has improved in the last decade, and these devices are cost-effective in patients with ischemic and nonischemic left ventricular dysfunction younger than 68 years, assuming willingness to pay as €25 000/QALY. For older nonischemic patients, the ICER was around €30 000/QALY (AU)

Long-Term Variation in Kidney Function and Its Impact After Acute Myocardial Infarction.

Kidney disease (KD) in patients with acute myocardial infarction (AMI) is associated with major cardiovascular events (MACE). We sought to compare the long-term variation in KD in patients with AMI versus controls and its value as a risk factor for MACE in patients with AMI. A cohort of 300 outpatients with AMI, recruited between 2014 and 2016 in Barcelona, Spain, were compared with a control cohort matched 1:1 based on age and several risk factors for developing KD. Annual estimated glomerular filtration rate (eGFR) using MDRD-4 formula and albuminuria were collected and patients were followed up for the occurrence of MACE (death, heart failure hospitalization, AMI, or stroke). After a median follow-up of 5.3 years, the decline in eGFR was more pronounced in patients with AMI (-1.15 ml/min/1.73 m2/ per year in patients with AMI vs -0.81 ml/min/1.73 m2 per year in controls, p = 0.018 between the ß coefficients of both regression slopes). In patients with AMI, those with the greatest eGFR decline during follow-up had more MACE (hazard ratio [HR] for first vs fourth quartiles = 3.33, p <0.001). In multivariate analysis, after excluding patients with baseline KD, a newly diagnosed eGFR <60 ml/min/1.73 m2 during follow-up was associated with MACE (HR = 3.21, p <0.001), as well as new onset albuminuria >30 mg/g (HR = 6.93, p <0.001) and the combination of both (HR 5.63, p <0.001). In conclusion, the decline in eGFR after AMI is more pronounced than in the general population. A longitudinal drop in eGFR and newly diagnosed albuminuria during follow-up are associated with MACE and can be useful tools to reclassify the risk profile after AMI.

Cost-effectiveness of implantable cardioverter-defibrillators for primary prevention of sudden cardiac death.

INTRODUCTION AND OBJECTIVES: Implantable cardioverter-defibrillators (ICD) are a cost-effective alternative for secondary prevention of sudden cardiac death, but their efficiency in primary prevention, especially among patients with nonischemic heart disease, is still uncertain. METHODS: We performed a cost-effectiveness analysis of ICD plus conventional medical treatment (CMT) vs CMT for primary prevention of cardiac arrhythmias from the perspective of the national health service. We simulated the course of the disease by using Markov models in patients with ischemic and nonischemic heart disease. The parameters of the model were based on the results obtained from a meta-analysis of clinical trials published between 1996 and 2018 comparing ICD plus CMT vs CMT, the safety results of the DANISH trial, and analysis of real-world clinical practice in a tertiary hospital. RESULTS: We estimated that ICD reduced the likelihood of all-cause death in patients with ischemic heart disease (HR, 0.70; 95%CI, 0.58-0.85) and in those with nonischemic heart disease (HR, 0.79; 95%CI, 0.66-0.96). The incremental cost-effectiveness ratio (ICER) estimated with probabilistic analysis was €19 171/quality adjusted life year (QALY) in patients with ischemic heart disease and €31 084/QALY in those with nonischemic dilated myocardiopathy overall and €23 230/QALY in patients younger than 68 years. CONCLUSIONS: The efficiency of single-lead ICD systems has improved in the last decade, and these devices are cost-effective in patients with ischemic and nonischemic left ventricular dysfunction younger than 68 years, assuming willingness to pay as €25 000/QALY. For older nonischemic patients, the ICER was around €30 000/QALY.

Cardiac biometric variables and arrhythmic events during COVID-19 pandemic lockdown in patients with an implantable cardiac monitor for syncope work-up

Aim: To assess the changes induced by the COVID-19 lockdown on cardiac biometric variables recorded using an implantable cardiac monitor (ICM) in a patient population monitored for syncope work-up, as well to assess whether there has been an effect on arrhythmic events among the patients.MethodsLongitudinal cohort study. We included 245 adult patients monitored with an ICM indicated for the investigation of syncope. The records from days 1 to 12 March 2020 (prior to the institution of lockdown by the state government) with days 16 to 28 March 2020 were compared.ResultsDaily physical exercise reduced markedly after the imposition of lockdown (132 [55–233] minutes vs. 78 [21–154] minutes). The mean daytime HR prior to lockdown was 77 [69–85] bpm, whereas during lockdown it was 74 [66–81] bpm. During the lockdown period, a drop in the variability in heart rate (114 [94–136] ms vs. 111 [92–133] ms) was observed. Although the incidence of AF was similar over both periods, the daily AF burden was significantly higher post-lockdown (405 [391–425] minutes vs. 423 [423–537] minutes). No differences in the number of other arrhythmias were found.ConclusionsThe establishment of mandatory lockdown has led to a marked drop in daily physical activity in this population which probably explains changes observed in other cardiac biometric variables. Although, in the short term, we have not documented an increased risk of arrhythmia, we cannot rule out an effect in the medium to long term or in other populations of at-risk patients. (AU)

Objetivo: Evaluar los cambios inducidos por el confinamiento durante la pandemia de COVID-19 en las variables biométricas cardiacas registradas, utilizando un monitor cardíaco implantable (ICM) en una población de pacientes monitorizada para el diagnóstico de síncope, así como evaluar si ha habido un efecto sobre los eventos arrítmicos.MétodosEstudio de cohorte prospectivo. Se incluyeron 245 pacientes adultos monitorizados con un ICM indicado para la investigación del síncope. Se compararon los registros de los días uno al 12 de marzo del 2020 (antes del establecimiento del confinamiento por parte del gobierno estatal) con los días 16 al 28 de marzo del 2020.ResultadosEl ejercicio físico diario se redujo notablemente después de la imposición del confinamiento (132 [55 a 233] vs. 78 [21 a 154] min). La frecuencia cardiaca diurna media antes del confinamiento fue de 77 (69 a 85) lpm, mientras que durante el mismo fue de 74 (66 a 81) lpm. Durante el período de confinamiento, se observó una disminución de la variabilidad de la frecuencia cardiaca (114 [94 a 136] vs. 111 [92 a 133] ms). Aunque la incidencia de fibrilación auricular (FA) fue similar en ambos períodos, la carga diaria de FA fue significativamente mayor después del bloqueo (405 [391 a 425] vs. 423 [423 a 537] min). No se encontraron diferencias en el número de otras arritmias.ConclusionesEl establecimiento de un confinamiento obligatorio ha provocado un marcado descenso de la actividad física diaria en esta población, lo que probablemente explica los cambios observados en otras variables biométricas cardiacas. Si bien, a corto plazo, no se ha documentado un aumento del riesgo de arritmia, no podemos descartar un efecto a medio-largo plazo o en otras poblaciones de pacientes de riesgo. (AU)

[Cardiac biometric variables and arrhythmic events during COVID-19 pandemic lockdown in patients with an implantable cardiac monitor for syncope work-up]. / Variables biométricas cardiacas y eventos arrítmicos durante el confinamiento por la pandemia de COVID-19 en pacientes portadores de un monitor cardiaco implantable para el diagnóstico de síncope.

AIM: To assess the changes induced by the COVID-19 lockdown on cardiac biometric variables recorded using an implantable cardiac monitor (ICM) in a patient population monitored for syncope work-up, as well to assess whether there has been an effect on arrhythmic events among the patients. METHODS: Longitudinal cohort study. We included 245 adult patients monitored with an ICM indicated for the investigation of syncope. The records from days 1 to 12 March 2020 (prior to the institution of lockdown by the state government) with days 16 to 28 March 2020 were compared. RESULTS: Daily physical exercise reduced markedly after the imposition of lockdown (132 [55-233] minutes vs. 78 [21-154] minutes). The mean daytime HR prior to lockdown was 77 [69-85] bpm, whereas during lockdown it was 74 [66-81] bpm. During the lockdown period, a drop in the variability in heart rate (114 [94-136] ms vs. 111 [92-133] ms) was observed. Although the incidence of AF was similar over both periods, the daily AF burden was significantly higher post-lockdown (405 [391-425] minutes vs. 423 [423-537] minutes). No differences in the number of other arrhythmias were found. CONCLUSIONS: The establishment of mandatory lockdown has led to a marked drop in daily physical activity in this population which probably explains changes observed in other cardiac biometric variables. Although, in the short term, we have not documented an increased risk of arrhythmia, we cannot rule out an effect in the medium to long term or in other populations of at-risk patients.

Etiology and prognosis of patients with unexplained syncope and mid-range left ventricular dysfunction.

BACKGROUND: Syncope in patients with mid-range left ventricular ejection fraction (LVEF) can be due to potentially serious arrhythmic causes. However, there is no clear consensus on the best way to manage these patients. OBJECTIVES: The objectives of this study were to determine the causes of syncope and assess the diagnostic yield and safety of a stepwise workup protocol in this population. METHODS: This was a prospective observational study. A stepwise workup protocol was applied to patients with LVEF 35%-50% and unexplained syncope after the initial assessment (step 1). RESULTS: One hundred four patients were included {median age 75.6 years; (interquartile range [IQR] 67.6-81.2 years); median LVEF 45% (IQR 40%-48%); median follow-up 2.0 years (IQR 0.7-3.3 years). In 71 patients (68.3%), a diagnosis was reached: 55 (77.5%) in step 2 (hospital admission and electrophysiology study) and 16 (36.5%) in step 3 (implantable cardiac monitor). Arrhythmic causes were the most common etiology (45.2% auriculoventricular block and 9.6% ventricular tachycardia). Sixty patients (57.7%) required the implantation of a cardiac device and 11 had a defibrillation function. Patients diagnosed in step 3 had a higher global risk of recurrence of syncope (hazard ratio 6.5; 95% confidence interval 2.3-18.0). The mortality rate was 8.1 per 100 person-years, and the sudden or unknown death rate was 0.9 per 100 person-years. CONCLUSION: In patients with mid-range left ventricular dysfunction and syncope of unknown cause, a systematic diagnostic strategy based on electrophysiology study and/or implantable cardiac monitor implantation allows a diagnosis to be reached in a high proportion of cases and guides the treatment. Arrhythmia is the most common cause of syncope in this population, particularly auriculoventricular block.

Cardiac biometric variables and arrhythmic events during COVID-19 pandemic lockdown in patients with an implantable cardiac monitor for syncope work-up.

Aim: To assess the changes induced by the COVID-19 lockdown on cardiac biometric variables recorded using an implantable cardiac monitor (ICM) in a patient population monitored for syncope work-up, as well to assess whether there has been an effect on arrhythmic events among the patients. Methods: Longitudinal cohort study. We included 245 adult patients monitored with an ICM indicated for the investigation of syncope. The records from days 1 to 12 March 2020 (prior to the institution of lockdown by the state government) with days 16 to 28 March 2020 were compared. Results: Daily physical exercise reduced markedly after the imposition of lockdown (132 [55-233] minutes vs. 78 [21-154] minutes). The mean daytime HR prior to lockdown was 77 [69-85] bpm, whereas during lockdown it was 74 [66-81] bpm. During the lockdown period, a drop in the variability in heart rate (114 [94-136] ms vs. 111 [92-133] ms) was observed. Although the incidence of AF was similar over both periods, the daily AF burden was significantly higher post-lockdown (405 [391-425] minutes vs. 423 [423-537] minutes). No differences in the number of other arrhythmias were found. Conclusions: The establishment of mandatory lockdown has led to a marked drop in daily physical activity in this population which probably explains changes observed in other cardiac biometric variables. Although, in the short term, we have not documented an increased risk of arrhythmia, we cannot rule out an effect in the medium to long term or in other populations of at-risk patients.

Objetivo: Evaluar los cambios inducidos por el confinamiento durante la pandemia de COVID-19 en las variables biométricas cardiacas registradas, utilizando un monitor cardíaco implantable (ICM) en una población de pacientes monitorizada para el diagnóstico de síncope, así como evaluar si ha habido un efecto sobre los eventos arrítmicos. Métodos: Estudio de cohorte prospectivo. Se incluyeron 245 pacientes adultos monitorizados con un ICM indicado para la investigación del síncope. Se compararon los registros de los días uno al 12 de marzo del 2020 (antes del establecimiento del confinamiento por parte del gobierno estatal) con los días 16 al 28 de marzo del 2020. Resultados: El ejercicio físico diario se redujo notablemente después de la imposición del confinamiento (132 [55 a 233] vs. 78 [21 a 154] min). La frecuencia cardiaca diurna media antes del confinamiento fue de 77 (69 a 85) lpm, mientras que durante el mismo fue de 74 (66 a 81) lpm. Durante el período de confinamiento, se observó una disminución de la variabilidad de la frecuencia cardiaca (114 [94 a 136] vs. 111 [92 a 133] ms). Aunque la incidencia de fibrilación auricular (FA) fue similar en ambos períodos, la carga diaria de FA fue significativamente mayor después del bloqueo (405 [391 a 425] vs. 423 [423 a 537] min). No se encontraron diferencias en el número de otras arritmias. Conclusiones: El establecimiento de un confinamiento obligatorio ha provocado un marcado descenso de la actividad física diaria en esta población, lo que probablemente explica los cambios observados en otras variables biométricas cardiacas. Si bien, a corto plazo, no se ha documentado un aumento del riesgo de arritmia, no podemos descartar un efecto a medio-largo plazo o en otras poblaciones de pacientes de riesgo.

Syncope in Patients With Severe Aortic Stenosis: More Than Just an Obstruction Issue.

BACKGROUND: Severe aortic stenosis (AoS) is considered a primary cause of syncope. However, other mechanisms may be present in these patients and accurate diagnosis can have important clinical implications. The aim of this study is to assess the different etiologies of syncope in patients with severe AoS and the impact on prognosis of attaining a certain or highly probable diagnosis for the syncope. METHODS: Out of a cohort of 331 patients with AoS and syncope, 61 had severe AoS and were included in the study. Main cause of syncope and adverse cardiac events were assessed. RESULTS: In 40 patients (65.6%), we reached a certain or highly probable diagnosis of the main cause of the syncope. AoS was considered the primary cause of the syncope in only 7 patients (17.5% of the patients with known etiology). Atrioventricular block (14 patients, 35.0%) and vasovagal syncope (6 patients, 15.0%) were the most frequently diagnosed causes. The presence of a known cause for syncope during the admission was not associated with a lower incidence of recurrence during follow-up (hazard ratio [HR] 0.69, 95% confidence interval [CI] 0.20-2.40). Syncope of unknown etiology was independently associated with greater mortality during 1-year follow-up (HR 5.4, 95% CI 1.3-21.6) and 3-year follow-up (HR 3.5, 95% CI 1.2-10.3). CONCLUSIONS: In a high proportion of patients with severe AoS admitted for syncope, the valvulopathy was not the main cause of the syncope. Syncope in two-thirds of this population was caused by either bradyarrhythmia or reflex causes. Syncope of unknown cause was associated with increased short- and medium-term mortality, independently from treatment of the valve disease. An exhaustive work-up should be conducted to determine the main cause for syncope.