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1.
Crit Care Med ; 45(7): e695-e702, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28403120

RESUMEN

OBJECTIVES: The aim of this study was to test the hypothesis that the right ventricle is more dilated during resuscitation from cardiac arrest caused by pulmonary embolism, compared with hypoxia and primary arrhythmia. DESIGN: Twenty-four pigs were anesthetized and cardiac arrest was induced using three different methods. Pigs were resuscitated after 7 minutes of untreated cardiac arrest. Ultrasonographic images were obtained and the right ventricular diameter was measured. SETTING: University hospital animal laboratory. SUBJECTS: Female crossbred Landrace/Yorkshire/Duroc pigs (27-32 kg). INTERVENTIONS: Pigs were randomly assigned to cardiac arrest induced by pulmonary embolism, hypoxia, or primary arrhythmia. MEASUREMENTS AND MAIN RESULTS: There was no difference at baseline. During induction of cardiac arrest, the right ventricle dilated in all groups (p < 0.01 for all). The primary endpoint was right ventricle diameter at the third rhythm analysis: 32 mm (95% CI, 29-36) for pulmonary embolism which was significantly larger than both hypoxia: 23 mm (95% CI, 20-27) and primary arrhythmia: 25 mm (95% CI, 22-28)-the absolute difference was 7-9 mm. Physicians with basic training in focused cardiac ultrasonography were able to detect a difference in right ventricle diameter of approximately 10 mm with a sensitivity of 79% (95% CI, 64-94) and a specificity of 68% (95% CI, 56-80). CONCLUSIONS: The right ventricle was more dilated during resuscitation when cardiac arrest was caused by pulmonary embolism compared with hypoxia and primary arrhythmia. However, the right ventricle was dilated, irrespective of the cause of arrest, and diagnostic accuracy by physicians with basic training in focused cardiac ultrasonography was modest. These findings challenge the paradigm that right ventricular dilatation on ultrasound during cardiopulmonary resuscitation is particularly associated with pulmonary embolism.


Asunto(s)
Paro Cardíaco/etiología , Paro Cardíaco/fisiopatología , Ventrículos Cardíacos/diagnóstico por imagen , Embolia Pulmonar/complicaciones , Embolia Pulmonar/fisiopatología , Animales , Reanimación Cardiopulmonar/métodos , Femenino , Porcinos , Ultrasonografía
2.
J Heart Valve Dis ; 25(6): 756-759, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-28290179

RESUMEN

Non-obstructive transcatheter heart valve (THV) thrombosis as a potential mechanism after stroke after transapical transcatheter aortic valve replacement (TAVR) is demonstrated by the present case report. By performing cardiac computed tomography (CT) in addition to standard transthoracic echocardiography (TTE) follow up after TAVR, it has been shown recently that non-obstructive THV thrombosis may be more common than previously anticipated. However, the clinical implications of non-obstructive THV thrombosis remain unclear. In the present patient, post-TAVR TTE and transeophageal echocardiography demonstrated normal THV function, and showed no evidence of THV thrombosis. In contrast, cardiac CT revealed findings consistent with THV thrombosis. The patient subsequently developed acute ischemic stroke that was treated with thrombolysis. Follow up cardiac CT and echocardiography demonstrated complete THV thrombus resolution.


Asunto(s)
Isquemia Encefálica/etiología , Trombosis/complicaciones , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Anciano , Estenosis de la Válvula Aórtica/cirugía , Isquemia Encefálica/diagnóstico por imagen , Ecocardiografía Transesofágica , Humanos , Imagen por Resonancia Magnética , Masculino , Tomografía Computarizada Multidetector , Complicaciones Posoperatorias/diagnóstico por imagen , Terapia Trombolítica , Trombosis/diagnóstico por imagen , Trombosis/tratamiento farmacológico
3.
Circulation ; 128(3): 244-53, 2013 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-23748467

RESUMEN

BACKGROUND: Aortic root rupture is a major concern with balloon-expandable transcatheter aortic valve replacement (TAVR). We sought to identify predictors of aortic root rupture during balloon-expandable TAVR by using multidetector computed tomography. METHODS AND RESULTS: Thirty-one consecutive patients who experienced left ventricular outflow tract (LVOT)/annular/aortic contained/noncontained rupture during TAVR were collected from 16 centers. A caliper-matched sample of 31 consecutive patients without annular rupture, who underwent pre-TAVR multidetector computed tomography served as a control group. Multidetector computed tomography assessment included short- and long-axis diameters and cross-sectional area of the sinotubular junction, annulus, and LVOT, and the presence, location, and extent of calcification of the LVOT, as well. There were no significant differences between the 2 groups in any preoperative clinical and echocardiographic variables. Aortic root rupture was identified in 20 patients and periaortic hematoma in 11. Patients with root rupture had a higher degree of subannular/LVOT calcification quantified by the Agatston score (181.2±211.0 versus 22.5±37.6, P<0.001), and a higher frequency of ≥20% annular area oversizing (79.4% versus 29.0%, P<0.001) and balloon postdilatation (22.6% versus 0.0%, P=0.005). In conditional logistic regression analysis for the matched data, moderate/severe LVOT/subannular calcifications (odds ratio, 10.92; 95% confidence interval, 3.23-36.91; P<0.001) and prosthesis oversizing ≥20% (odds ratio, 8.38; 95% confidence interval, 2.67-26.33; P<0.001) were associated with aortic root contained/noncontained rupture. CONCLUSIONS: This study demonstrates that LVOT calcification and aggressive annular area oversizing are associated with an increased risk of aortic root rupture during TAVR with balloon-expandable prostheses. Larger studies are warranted to confirm these findings.


Asunto(s)
Angioplastia de Balón/efectos adversos , Rotura de la Aorta/etiología , Estenosis de la Válvula Aórtica/terapia , Cateterismo Cardíaco , Implantación de Prótesis de Válvulas Cardíacas/efectos adversos , Anciano , Anciano de 80 o más Años , Rotura de la Aorta/diagnóstico por imagen , Rotura de la Aorta/epidemiología , Válvula Aórtica/diagnóstico por imagen , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Estenosis de la Válvula Aórtica/epidemiología , Calcinosis/complicaciones , Calcinosis/diagnóstico por imagen , Calcinosis/epidemiología , Estudios de Cohortes , Femenino , Implantación de Prótesis de Válvulas Cardíacas/métodos , Humanos , Modelos Logísticos , Masculino , Valor Predictivo de las Pruebas , Factores de Riesgo , Tomografía Computarizada por Rayos X
4.
Catheter Cardiovasc Interv ; 82(6): 977-86, 2013 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-23703899

RESUMEN

OBJECTIVES: In transcatheter aortic valve replacement (TAVR), the influence of aortic annular assessment with either multidetector computed tomography (MDCT) or conventional transesophageal echocardiography (TEE) on the incidence of postprocedural paravalvular aortic regurgitation (PAR) was evaluated. BACKGROUND: PAR remains a major limitation in TAVR. Appropriate selection of transcatheter heart valve (THV) size is crucial to prevent PAR. METHODS: Outcomes following TAVR with a balloon-expandable THV were compared in two retrospective cohorts identified according to whether THV size selection was based on TEE (study group 1, n = 80) or MDCT (study group 2, n = 58). RESULTS: The two study groups were comparable with regard to baseline clinical, risk score, and echocardiographic characteristics. The incidence of moderate/severe PAR was lower in study group 2 than in group 1, 8.6% versus 28.8% (P < 0.01). The difference between the THV nominal diameter and MDCT annular diameter was predictive of moderate/severe PAR (AUC 0.84; 95% CI: 0.72-0.92). Neither age, gender, body mass index, annular eccentricity index, aortic valve calcification nor the difference between the THV diameter and the TEE annular diameter predicted postprocedural PAR. Increased THV oversizing relative to the MDCT mean annular diameter was associated with reduced severity of PAR. No difference in perprocedural complications between two study groups was observed. CONCLUSION: MDCT-based annular sizing in TAVR significantly reduces postprocedural PAR, and THV oversizing appears pivotal in this aspect. Further delineation of the optimal degree of THV oversizing is needed.


Asunto(s)
Insuficiencia de la Válvula Aórtica/prevención & control , Estenosis de la Válvula Aórtica/terapia , Válvula Aórtica/diagnóstico por imagen , Cateterismo Cardíaco , Ecocardiografía Transesofágica , Implantación de Prótesis de Válvulas Cardíacas , Prótesis Valvulares Cardíacas , Imagenología Tridimensional , Tomografía Computarizada Multidetector , Diseño de Prótesis , Anciano , Anciano de 80 o más Años , Insuficiencia de la Válvula Aórtica/epidemiología , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Cateterismo Cardíaco/efectos adversos , Cateterismo Cardíaco/instrumentación , Dinamarca/epidemiología , Femenino , Implantación de Prótesis de Válvulas Cardíacas/efectos adversos , Implantación de Prótesis de Válvulas Cardíacas/instrumentación , Humanos , Incidencia , Masculino , Valor Predictivo de las Pruebas , Interpretación de Imagen Radiográfica Asistida por Computador , Estudios Retrospectivos , Resultado del Tratamiento
5.
Open Heart ; 10(2)2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37487656

RESUMEN

INTRODUCTION: Current guideline recommend functional imaging for myocardial ischaemia if coronary CT angiography (CTA) has shown coronary artery disease (CAD) of uncertain functional significance. However, diagnostic accuracy of selective myocardial perfusion imaging after coronary CTA is currently unclear. The Danish study of Non-Invasive testing in Coronary Artery Disease 3 trial is designed to evaluate head to head the diagnostic accuracy of myocardial perfusion imaging with positron emission tomography (PET) using the tracers 82Rubidium (82Rb-PET) compared with oxygen-15 labelled water PET (15O-water-PET) in patients with symptoms of obstructive CAD and a coronary CT scan with suspected obstructive CAD. METHODS AND ANALYSIS: This prospective, multicentre, cross-sectional study will include approximately 1000 symptomatic patients without previous CAD. Patients are included after referral to coronary CTA. All patients undergo a structured interview and blood is sampled for genetic and proteomic analysis and a coronary CTA. Patients with possible obstructive CAD at coronary CTA are examined with both 82Rb-PET, 15O-water-PET and invasive coronary angiography with three-vessel fractional flow reserve and thermodilution measurements of coronary flow reserve. After enrolment, patients are followed with Seattle Angina Questionnaires and follow-up PET scans in patients with an initially abnormal PET scan and for cardiovascular events in 10 years. ETHICS AND DISSEMINATION: Ethical approval was obtained from Danish regional committee on health research ethics. Written informed consent will be provided by all study participants. Results of this study will be disseminated via articles in international peer-reviewed journal. TRIAL REGISTRATION NUMBER: NCT04707859.


Asunto(s)
Enfermedad de la Arteria Coronaria , Reserva del Flujo Fraccional Miocárdico , Humanos , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Estudios Transversales , Dinamarca , Estudios Prospectivos , Proteómica , Agua , Estudios Multicéntricos como Asunto
6.
EuroIntervention ; 17(13): 1061-1069, 2022 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-34338638

RESUMEN

BACKGROUND: There are limited data on the association of membranous septum (MS) morphology and transcatheter heart valve (THV) implantation depth, and the development of new conduction abnormalities (CA) after transcatheter aortic valve implantation (TAVI). AIMS: The aim of this study was to describe the morphology of the MS and predict the risk of new CA after TAVI based on the MS morphology and THV implantation depth. METHODS: Based on preprocedural CT scans, the MS depth was measured for every 25% of the entire MS width in 272 TAVI patients without preprocedural bundle branch block (BBB) or pacemaker. Post-procedural CT scans for THV implantation depth assessment were available in 130 of these patients. RESULTS: The MS depth was a median of 2.5 mm (IQR 1.4-3.8) deeper at the posterior edge when compared to the anterior edge of the MS. New CA developed in 7.1% of patients in whom the THV did not cross the lower MS border at its anterior edge (3.6% with new BBB and high degree CA, respectively), in 18.8% of patients (15.6% with new BBB and 3.1% with new high-degree CA) where the THV overlapped the lower MS border by <2.5 mm and in 47.1% of patients (24.3% with new BBB and 22.9% with new high-degree CA) with THV overlap of the lower MS border by ≥2.5 mm. CONCLUSIONS: The difference of the MS depth and THV implantation depth measured at the anterior edge of the MS predicted new CA after TAVI.


Asunto(s)
Estenosis de la Válvula Aórtica , Prótesis Valvulares Cardíacas , Marcapaso Artificial , Reemplazo de la Válvula Aórtica Transcatéter , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/cirugía , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Estenosis de la Válvula Aórtica/cirugía , Bloqueo de Rama/terapia , Humanos , Estudios Retrospectivos , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Resultado del Tratamiento
7.
Int J Cardiovasc Imaging ; 38(3): 695-705, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34655348

RESUMEN

Hypo-attenuated leaflet thickening (HALT) of transcatheter aortic valves is detected on multidetector computed tomography (MDCT) and reflects leaflet thrombosis. Whether HALT affects left ventricular (LV) reverse remodeling, a favorable effect of LV afterload reduction after transcatheter aortic valve implantation (TAVI) is unknown. The aim of this study was to examine the association of HALT after TAVI with LV reverse remodeling. In this multicenter case-control study, patients with HALT on MDCT were identified, and patients without HALT were propensity matched for valve type and size, LV ejection fraction (LVEF), sex, age and time of scan. LV dimensions and function were assessed by transthoracic echocardiography before and 12 months after TAVI. Clinical outcomes (stroke or transient ischemic attack, heart failure hospitalization, new-onset atrial fibrillation, all-cause mortality) were recorded. 106 patients (age 81 ± 7 years, 55% male) with MDCT performed 37 days [IQR 32-52] after TAVI were analyzed (53 patients with HALT and 53 matched controls). Before TAVI, all echocardiographic parameters were similar between the groups. At 12 months follow-up, patients with and without HALT showed a significant reduction in LV end-diastolic volume, LV end-systolic volume and LV mass index (from 125 ± 37 to 105 ± 46 g/m2, p = 0.001 and from 127 ± 35 to 101 ± 27 g/m2, p < 0.001, respectively, p for interaction = 0.48). Moreover, LVEF improved significantly in both groups. In addition, clinical outcomes were not statistically different. Improvement in LVEF and LV reverse remodeling at 12 months after TAVI were not limited by HALT.


Asunto(s)
Estenosis de la Válvula Aórtica , Trombosis , Reemplazo de la Válvula Aórtica Transcatéter , Anciano , Anciano de 80 o más Años , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/cirugía , Estenosis de la Válvula Aórtica/complicaciones , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Estenosis de la Válvula Aórtica/cirugía , Estudios de Casos y Controles , Femenino , Estudios de Seguimiento , Humanos , Masculino , Valor Predictivo de las Pruebas , Trombosis/complicaciones , Trombosis/etiología , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Resultado del Tratamiento , Función Ventricular Izquierda , Remodelación Ventricular
8.
EuroIntervention ; 16(1): 83-88, 2020 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-32011285

RESUMEN

AIMS: The purpose of this registry was to determine the long-term outcomes in patients with asymptomatic contained annulus rupture (CR) as a rare complication of transcatheter aortic valve implantation (TAVI). METHODS AND RESULTS: The ENCORE registry is a multicentre registry (six centres across Europe) of patients with CR diagnosed on post-TAVI computed tomography angiography (CTA) or transoesophageal echocardiography (TEE). A total of 21 patients (mean age 81.9±4.1 years, 81% balloon-expandable TAVI prostheses) were diagnosed with CR (mean size of lesions was 15.3±6.9 × 8.5±3.3 × 8.5±2.3 mm). Seventeen were diagnosed among a total of 1,602 consecutive routine post-TAVI CTA (incidence 1.1%), two in TEE and two in post-TAVI CTA (each conducted due to suspicion of peri-interventional complications). During a mean follow-up of 2.3±1.7 years (cumulative 48.6 patient-years), nine patients (43%) died from non-cardiac causes. None of the patients exhibited symptoms or underwent interventional treatment related to the CR; no sudden cardiac death occurred. A follow-up CTA, performed in eleven patients 240±176 days post TAVI, revealed stable CR findings in seven, regression in one, and remission in three patients. CONCLUSIONS: The results of our international multicentre registry demonstrate favourable long-term outcomes of CR after TAVI supporting a watch-and-wait strategy in these patients.


Asunto(s)
Estenosis de la Válvula Aórtica , Implantación de Prótesis de Válvulas Cardíacas , Prótesis Valvulares Cardíacas , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Anciano , Anciano de 80 o más Años , Válvula Aórtica , Europa (Continente) , Estudios de Seguimiento , Humanos , Estudios Longitudinales , Sistema de Registros , Factores de Tiempo , Resultado del Tratamiento
9.
J Cardiovasc Comput Tomogr ; 12(4): 290-297, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29519754

RESUMEN

OBJECTIVES: We sought to determine the impact of aortic root calcium on the risk of significant paravalvular regurgitation (sPAR) in transcatheter aortic valve replacement (TAVR). METHODS: In 302 consecutive patients from 3 centers, aortic root calcium was quantified volumetrically on pre-TAVR multidetector computed tomography (MDCT) in three regions: 1) the aortic valve region, 2) the overall left ventricular outflow tract (LVOT) and 3) the upper LVOT. Transcathether heart valve (THV) oversizing was calculated as (THV nominal area/MDCT annular area-1) × 100. The study endpoint sPAR was a composite of post-dilatation (PD) and PAR > mild. RESULTS: sPAR occurred in 15% (46/302) of patients. Upper LVOT calcium volume was more predictive of sPAR than overall LVOT calcium volume, with an area under the receiver operating curve (AUC) (95% confidence interval [CI]) of 0.80 (0.67-0.89) vs. 0.60 (0.51-0.70); p = 0.0001. The optimal cut-off calcium volume thresholds determined from receiver operating curves were 21 mm3 and 30 mm3 for upper LVOT and overall LVOT calcium, respectively. Upper LVOT calcium ≥ 21 mm3, but not overall LVOT calcium ≥ 30 mm3, independently predicted sPAR, odds ratio (95%CI): 9.5 (4.1-22.3) vs 1.6 (0.6-2.7). Upper LVOT calcium was more predictive of sPAR in patients with THV oversizing ≥ 13% compared to patients with THV oversizing <13%, AUC (95% CI): 0.83 (0.72-0.93) vs. 0.67 (0.51-0.74); p < 0.0001. CONCLUSIONS: Upper LVOT calcium predicts more-than-mild paravalvular regurgitation following TAVR or the need for postdilatation. Upper LVOT calcium is most predictive of paravalvular regurgitation in the event of THV oversizing ≥ 13%.


Asunto(s)
Insuficiencia de la Válvula Aórtica/etiología , Estenosis de la Válvula Aórtica/cirugía , Válvula Aórtica/patología , Válvula Aórtica/trasplante , Calcinosis/cirugía , Calcio/metabolismo , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Anciano , Anciano de 80 o más Años , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/metabolismo , Válvula Aórtica/fisiopatología , Válvula Aórtica/cirugía , Insuficiencia de la Válvula Aórtica/diagnóstico por imagen , Insuficiencia de la Válvula Aórtica/fisiopatología , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Estenosis de la Válvula Aórtica/metabolismo , Estenosis de la Válvula Aórtica/fisiopatología , Área Bajo la Curva , Colombia Británica , Calcinosis/diagnóstico por imagen , Calcinosis/metabolismo , Calcinosis/fisiopatología , Distribución de Chi-Cuadrado , Dinamarca , Ecocardiografía Transesofágica , Femenino , Prótesis Valvulares Cardíacas , Ventrículos Cardíacos/diagnóstico por imagen , Ventrículos Cardíacos/metabolismo , Ventrículos Cardíacos/fisiopatología , Humanos , Modelos Logísticos , Londres , Masculino , Tomografía Computarizada Multidetector , Análisis Multivariante , Oportunidad Relativa , Valor Predictivo de las Pruebas , Modelos de Riesgos Proporcionales , Diseño de Prótesis , Curva ROC , Reproducibilidad de los Resultados , Factores de Riesgo , Índice de Severidad de la Enfermedad , Factores de Tiempo , Reemplazo de la Válvula Aórtica Transcatéter/instrumentación , Resultado del Tratamiento
10.
Am J Case Rep ; 18: 573-575, 2017 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-28536415

RESUMEN

BACKGROUND Although transcatheter aortic valve replacement (TAVR) has become a worldwide and generally accepted treatment of patients with aortic stenosis at high surgical risk, there is a rising concern and debate about the occurrence of transcatheter heart valve (THV) thrombosis and its impact on TAVR outcome. It seems that the incidence of THV thrombosis is higher than first anticipated, but uncertainty remains regarding how to prevent and how to treat it. Hence, there is an urgent need for understanding THV thrombosis and to communicate experiences within the field. CASE REPORT We present a unique case of late occurrence of THV thrombosis that was resolved by switching from clopidogrel to rivaroxaban treatment. CONCLUSIONS As a novel observation, our case demonstrates that THV thrombosis may develop even late after TAVR, and even in such cases may be completely reversed. It also underscores that THV dysfunction should evoke prompt investigation for possible thrombus formation, preferable by multidetector computed tomography. Finally, this case report suggests NOAC as an alternative to warfarin treatment in patients with THV thrombosis.


Asunto(s)
Inhibidores del Factor Xa/uso terapéutico , Prótesis Valvulares Cardíacas/efectos adversos , Rivaroxabán/uso terapéutico , Trombosis/tratamiento farmacológico , Reemplazo de la Válvula Aórtica Transcatéter , Anciano , Estenosis de la Válvula Aórtica/cirugía , Humanos , Masculino
11.
JACC Cardiovasc Imaging ; 10(5): 541-550, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-27085447

RESUMEN

OBJECTIVES: The goal of this study was to assess the real-world clinical utility of fractional flow reserve (FFR) derived from coronary computed tomography angiography (FFRCT) for decision-making in patients with stable coronary artery disease (CAD). BACKGROUND: FFRCT has shown promising results in identifying lesion-specific ischemia. The real-world feasibility and influence on the diagnostic work-up of FFRCT testing in patients suspected of having CAD are unknown. METHODS: We reviewed the complete diagnostic work-up of nonemergent patients referred for coronary computed tomography angiography over a 12-month period at Aarhus University Hospital, Denmark, including all patients with new-onset chest pain with no known CAD and with intermediate-range coronary lesions (lumen reduction, 30% to 70%) referred for FFRCT. The study evaluated the consequences on downstream diagnostic testing, the agreement between FFRCT and invasively measured FFR or instantaneous wave-free ratio (iFR), and the short-term clinical outcome after FFRCT testing. RESULTS: Among 1,248 patients referred for computed tomography angiography, 189 patients (mean age 59 years; 59% male) were referred for FFRCT, with a conclusive FFRCT result obtained in 185 (98%). FFRCT was ≤0.80 in 31% of patients and 10% of vessels. After FFRCT testing, invasive angiography was performed in 29%, with FFR measured in 19% and iFR in 1% of patients (with a tendency toward declining FFR-iFR guidance during the study period). FFRCT ≤0.80 correctly classified 73% (27 of 37) of patients and 70% (37 of 53) of vessels using FFR ≤0.80 or iFR ≤0.90 as the reference standard. In patients with FFRCT >0.80 being deferred from invasive coronary angiography, no adverse cardiac events occurred during a median follow-up period of 12 (range 6 to 18 months) months. CONCLUSIONS: FFRCT testing is feasible in real-world symptomatic patients with intermediate-range stenosis determined by coronary computed tomography angiography. Implementation of FFRCT for clinical decision-making may influence the downstream diagnostic workflow of patients. Patients with an FFRCT value >0.80 being deferred from invasive coronary angiography have a favorable short-term prognosis.


Asunto(s)
Toma de Decisiones Clínicas , Angiografía por Tomografía Computarizada , Angiografía Coronaria/métodos , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Vasos Coronarios/diagnóstico por imagen , Reserva del Flujo Fraccional Miocárdico , Adulto , Anciano , Anciano de 80 o más Años , Enfermedad de la Arteria Coronaria/fisiopatología , Enfermedad de la Arteria Coronaria/terapia , Vasos Coronarios/fisiopatología , Dinamarca , Estudios de Factibilidad , Femenino , Hospitales Universitarios , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico
12.
J Am Coll Cardiol ; 68(19): 2059-2069, 2016 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-27580689

RESUMEN

BACKGROUND: There are limited data on the incidence, clinical implications, and predisposing factors of transcatheter heart valve (THV) thrombosis following transcatheter aortic valve replacement (TAVR). OBJECTIVES: The authors assessed the incidence, potential predictors, and clinical implications of THV thrombosis as determined by contrast-enhanced multidetector computed tomography (MDCT) after TAVR. METHODS: Among 460 consecutive patients who underwent TAVR with the Edwards Sapien XT or Sapien 3 (Edwards Lifesciences, Irvine, California) THV, 405 (88%) underwent MDCT in addition to transthoracic and transesophageal echocardiography 1 to 3 months post-TAVR. MDCT scans were evaluated for hypoattenuated leaflet thickening that indicated THV thrombosis. RESULTS: MDCT verified THV thrombosis in 28 of 405 (7%) patients. A total of 23 patients had subclinical THV thrombosis, whereas 5 (18%) patients experienced clinically overt obstructive THV thrombosis. THV thrombosis risk did not differ among different generations of THVs (8% vs. 6%; p = 0.42). The risk of THV thrombosis in patients who did not receive warfarin was higher compared with patients who received warfarin (10.7% vs. 1.8%; risk ratio [RR]: 6.09; 95% confidence interval [CI]: 1.86 to 19.84). A larger THV was associated with an increased risk of THV thrombosis (p = 0.03). In multivariable analysis, a 29-mm THV (RR: 2.89; 95% CI: 1.44 to 5.80) and no post-TAVR warfarin treatment (RR: 5.46; 95% CI: 1.68 to 17.7) independently predicted THV thrombosis. Treatment with warfarin effectively reverted THV thrombosis and normalized THV function in 85% of patients as documented by follow-up transesophageal echocardiography and MDCT. CONCLUSIONS: Incidence of THV thrombosis in this large study was 7%. A larger THV size may predispose to THV thrombosis, whereas treatment with warfarin appears to have a protective effect. Although often subclinical, THV thrombosis may have important clinical implications.


Asunto(s)
Estenosis de la Válvula Aórtica/cirugía , Válvula Aórtica/diagnóstico por imagen , Complicaciones Posoperatorias/epidemiología , Trombosis/epidemiología , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Anciano , Anciano de 80 o más Años , Válvula Aórtica/cirugía , Estenosis de la Válvula Aórtica/diagnóstico , Dinamarca/epidemiología , Ecocardiografía Transesofágica , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Masculino , Tomografía Computarizada Multidetector , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/etiología , Pronóstico , Estudios Retrospectivos , Trombosis/diagnóstico , Trombosis/etiología
14.
Circ Cardiovasc Interv ; 8(4)2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25873726

RESUMEN

BACKGROUND: Early stent valve thrombosis after transcatheter aortic valve implantation (TAVI) is a rare complication, which is diagnosed based on the appearance of clinical symptoms of heart failure and echocardiographic findings. After TAVI, transthoracic echocardiography is performed to assess transcatheter heart valve (THV) function. However, preliminary reports indicate the potential additive clinical value of multidetector computed tomography (MDCT) for the diagnosis of THV thrombosis. We sought to determine the value of MDCT for the diagnosis of THV thrombosis and the frequency of this complication after balloon-expandable TAVI. METHODS AND RESULTS: MDCT was performed in 140 patients within 1 to 3 months after TAVI with the Edwards Sapien XT THV to assess the presence of THV thrombosis and THV stent geometry. Post-TAVI MDCT identified THV thrombosis in 5 patients (4%). Of note, 4 of these patients were asymptomatic and had a normal transthoracic echocardiographic examination without signs of thrombus formation or flow obstruction. In patients with THV thrombosis, a left ventricular ejection fraction of <35% was present in 3 (60%), whereas 2 (40%) did not receive standard post-TAVI dual-antiplatelet therapy. Neither THV underexpansion nor THV noncircularity was detected in patients with THV thrombosis. CONCLUSIONS: Post-TAVI MDCT is a valuable tool for the diagnosis of THV thrombosis, and this complication seems to be more common than previously anticipated. Larger studies are required to identify specific risk factors of THV thrombosis.


Asunto(s)
Estenosis de la Válvula Aórtica/diagnóstico , Válvula Aórtica/diagnóstico por imagen , Tomografía Computarizada Multidetector/métodos , Complicaciones Posoperatorias/diagnóstico , Trombosis/diagnóstico , Reemplazo de la Válvula Aórtica Transcatéter , Anciano , Anciano de 80 o más Años , Válvula Aórtica/patología , Válvula Aórtica/cirugía , Estenosis de la Válvula Aórtica/cirugía , Estudios de Cohortes , Ecocardiografía , Femenino , Humanos , Masculino , Valor Predictivo de las Pruebas , Pronóstico , Stents/estadística & datos numéricos , Trombosis/etiología
15.
JACC Cardiovasc Interv ; 8(13): 1727-32, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26476612

RESUMEN

OBJECTIVES: The aim of this study was to evaluate a strategy of intentional underexpansion of excessively oversized balloon-expandable transcatheter heart valves (THVs) in terms of clinical outcomes, valve function, and frame durability at 1 year. BACKGROUND: Transcatheter aortic valve replacement requires the selection of an optimally sized THV to ensure paravalvular sealing and fixation without risking annular injury. However, some patients have "borderline" annular dimensions that require choosing between a THV that may be too small or another that may be too large. METHODS: We evaluated 47 patients at risk of annular injury who underwent transcatheter aortic valve replacement (TAVR) with an oversized, but deliberately underexpanded, THV followed by post-dilation if required. Clinical evaluation, echocardiography, and cardiac computed tomography were performed pre-TAVR, post-TAVR, and at 1 year. RESULTS: Deployment of oversized THVs with modest underfilling of the deployment balloon (<10% by volume) was not associated with significant annular injury. Paravalvular regurgitation was mild or less in 95.7% of patients, with post-dilation required in 10.7%. THV hemodynamic function was excellent and remained stable at 1 year. Computed tomography documented stent frame circularity in 87.5%. Underexpansion was greatest within the intra-annular THV inflow (stent frame area 85.8% of nominal). There was no evidence of stent frame recoil, deformation, or fracture at 1 year. CONCLUSIONS: In carefully selected patients with borderline annulus dimensions and in whom excessive oversizing of a balloon-expandable SAPIEN XT valve (Edwards Lifesciences, Inc., Irvine, California) is a concern, a strategy of deliberate underexpansion, with ad hoc post-dilation, if necessary, may reduce the risk of annular injury without compromising valve performance.


Asunto(s)
Estenosis de la Válvula Aórtica/terapia , Válvula Aórtica , Valvuloplastia con Balón/métodos , Cateterismo Cardíaco/métodos , Lesiones Cardíacas/prevención & control , Implantación de Prótesis de Válvulas Cardíacas/métodos , Anciano , Anciano de 80 o más Años , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/lesiones , Válvula Aórtica/fisiopatología , Insuficiencia de la Válvula Aórtica/etiología , Insuficiencia de la Válvula Aórtica/prevención & control , Estenosis de la Válvula Aórtica/diagnóstico , Estenosis de la Válvula Aórtica/fisiopatología , Valvuloplastia con Balón/efectos adversos , Cateterismo Cardíaco/efectos adversos , Cateterismo Cardíaco/instrumentación , Femenino , Lesiones Cardíacas/diagnóstico , Lesiones Cardíacas/etiología , Prótesis Valvulares Cardíacas , Implantación de Prótesis de Válvulas Cardíacas/efectos adversos , Implantación de Prótesis de Válvulas Cardíacas/instrumentación , Hemodinámica , Humanos , Masculino , Selección de Paciente , Diseño de Prótesis , Medición de Riesgo , Factores de Riesgo , Índice de Severidad de la Enfermedad , Factores de Tiempo , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Ultrasonografía
16.
JACC Cardiovasc Imaging ; 8(9): 1045-1055, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26298072

RESUMEN

OBJECTIVES: The goal of this study was to examine the diagnostic performance of noninvasive fractional flow reserve (FFR) derived from coronary computed tomography angiography (CTA) (FFRCT) in relation to coronary calcification severity. BACKGROUND: FFRCT has shown promising results in identifying lesion-specific ischemia. The extent to which the severity of coronary calcification affects the diagnostic performance of FFRCT is not known. METHODS: Coronary calcification was assessed by using the Agatston score (AS) in 214 patients suspected of having coronary artery disease who underwent coronary CTA, FFRCT, and FFR (FFR examination was performed in 333 vessels). The diagnostic performance of FFRCT (≤0.80) in identifying vessel-specific ischemia (FFR ≤0.80) was investigated across AS quartiles (Q1 to Q4) and for discrimination of ischemia in patients and vessels with a low-mid AS (Q1 to Q3) versus a high AS (Q4). Coronary CTA stenosis was defined as lumen reduction >50%. RESULTS: Mean ± SD per-patient and per-vessel AS were 302 ± 468 (range 0 to 3,599) and 95 ± 172 (range 0 to 1,703), respectively. There was no statistical difference in diagnostic accuracy, sensitivity, or specificity of FFRCT across AS quartiles. Discrimination of ischemia by FFRCT was high in patients with a high AS (416 to 3,599) and a low-mid AS (0 to 415), with no difference in area under the receiver-operating characteristic curve (AUC) (0.86 [95% confidence interval (CI): 0.76 to 0.96] vs. 0.92 [95% CI: 0.88 to 0.96]) (p = 0.45). Similarly, discrimination of ischemia by FFRCT was high in vessels with a high AS (121 to 1,703) and a low-mid AS (0 to 120) (AUC: 0.91 [95% CI: 0.85 to 0.97] vs. 0.95 [95% CI: 0.91 to 0.98]; p = 0.65). Diagnostic accuracy and specificity of FFRCT were significantly higher than for stenosis assessment in each AS quartile at the per-patient (p < 0.001) and per-vessel (p < 0.05) level with similar sensitivity. In vessels with a high AS, FFRCT exhibited improved discrimination of ischemia compared with coronary CTA alone (AUC: 0.91 vs. 0.71; p = 0.004), whereas on a per-patient level, the difference did not reach statistical significance (AUC: 0.86 vs. 0.72; p = 0.09). CONCLUSIONS: FFRCT provided high and superior diagnostic performance compared with coronary CTA interpretation alone in patients and vessels with a high AS.


Asunto(s)
Angiografía Coronaria/métodos , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Estenosis Coronaria/diagnóstico por imagen , Vasos Coronarios/diagnóstico por imagen , Reserva del Flujo Fraccional Miocárdico , Tomografía Computarizada por Rayos X , Calcificación Vascular/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Área Bajo la Curva , Enfermedad de la Arteria Coronaria/fisiopatología , Estenosis Coronaria/fisiopatología , Vasos Coronarios/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , Curva ROC , Reproducibilidad de los Resultados , Índice de Severidad de la Enfermedad , Calcificación Vascular/fisiopatología
17.
JACC Cardiovasc Interv ; 8(3): 462-471, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25790764

RESUMEN

OBJECTIVES: This study sought to compare the influence of the extent of multidetector computed tomography (MDCT) area oversizing on the incidence of paravalvular aortic regurgitation (PAR) between the Sapien 3 and the Sapien XT transcatheter heart valve (THV) to define a new MDCT sizing guideline suitable for the Sapien 3 platform. BACKGROUND: The inverse relationship of PAR occurrence and oversizing has been demonstrated for the Sapien XT but the incidence of PAR with comparable oversizing with the Sapien 3 is not known. METHODS: Sixty-one prospectively enrolled patients who underwent transcatheter aortic valve replacement with the Sapien 3 THV were compared with 92 patients who underwent transcatheter aortic valve replacement with the Sapien XT THV. Patients were categorized depending on the degree of MDCT area oversizing percentage: undersizing (below 0%), 0% to 5%, 5% to 10%, and above 10%. The primary endpoint was mild or greater PAR on transthoracic echocardiography. RESULTS: Mild or greater PAR was present in 19.7% of patients (12 of 61) in the Sapien 3 group and in 54.3% of patients (50 of 92) in the Sapien XT group (p < 0.01). The Sapien 3 group, compared with the Sapien XT group, consistently demonstrated significantly lower rates of mild or greater PAR except for oversizing >10% (p for interaction = 0.54). Moderate or severe PAR rates were also lower in the Sapien 3 group than in the Sapien XT group (3.3% vs. 13.0%, p = 0.04). In the Sapien 3 group, a MDCT area oversizing percentage value of ≤4.17% was identified as the optimal cutoff value to discriminate patients with or without mild or greater PAR. CONCLUSIONS: Our retrospective analysis suggests that the Sapien 3 THV displays significantly lower rates of PAR than does the Sapien XT THV. A lesser degree of MDCT area oversizing may be employed for this new balloon-expandable THV.


Asunto(s)
Insuficiencia de la Válvula Aórtica/epidemiología , Estenosis de la Válvula Aórtica/terapia , Válvula Aórtica/diagnóstico por imagen , Cateterismo Cardíaco/efectos adversos , Cateterismo Cardíaco/instrumentación , Implantación de Prótesis de Válvulas Cardíacas/efectos adversos , Implantación de Prótesis de Válvulas Cardíacas/instrumentación , Prótesis Valvulares Cardíacas , Tomografía Computarizada Multidetector , Anciano , Anciano de 80 o más Años , Válvula Aórtica/fisiopatología , Insuficiencia de la Válvula Aórtica/diagnóstico , Insuficiencia de la Válvula Aórtica/fisiopatología , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Estenosis de la Válvula Aórtica/fisiopatología , Canadá/epidemiología , Ecocardiografía Doppler en Color , Ecocardiografía Transesofágica , Europa (Continente)/epidemiología , Femenino , Hemodinámica , Humanos , Incidencia , Masculino , Valor Predictivo de las Pruebas , Diseño de Prótesis , Estudios Retrospectivos , Factores de Riesgo , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
18.
J Cardiovasc Comput Tomogr ; 9(5): 382-92, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26164109

RESUMEN

BACKGROUND: A detailed assessment of calcium within the aortic root may provide important additional information regarding the risk of aortic root injury during transcatheter heart valve replacement (TAVR). OBJECTIVE: We sought to delineate the effect of calcium volume and distribution on aortic root injury during TAVR. METHODS: Thirty-three patients experiencing aortic root injury during TAVR with a balloon-expandable valve were compared with a control group of 153 consecutive TAVR patients without aortic root injury (as assessed by post-TAVR multidetector CT). Using commercial software to analyze contrast-enhanced pre-TAVR CT scans, calcium volume was determined in 3 regions: (1) the overall left ventricular outflow tract (LVOT), extending 10 mm down from the aortic annulus plane; (2) the upper LVOT, extending 2 mm down from the annulus plane; and (3) the aortic valve region. RESULTS: Calcium volumes in the upper LVOT (median, 29 vs 0 mm(3); P < .0001) and overall LVOT (median, 74 vs 3 mm(3); P = .0001) were higher in patients who experienced aortic root injury compared with the control group. Calcium in the aortic valve region did not differ between groups. Upper LVOT calcium volume was more predictive of aortic root injury than overall LVOT calcium volume (area under receiver operating curve [AUC], 0.78; 95% confidence interval, 0.69-0.86 vs AUC, 0.71; 95% confidence interval, 0.62-0.82; P = .010). Upper LVOT calcium below the noncoronary cusp was significantly more predictive of aortic root injury compared to calcium underneath the right coronary cusp or the left coronary cusp (AUC, 0.81 vs 0.68 vs 0.64). Prosthesis oversizing >20% (likelihood ratio test, P = .028) and redilatation (likelihood ratio test, P = .015) improved prediction of aortic root injury by upper LVOT calcium volume. CONCLUSION: Calcification of the LVOT, especially in the upper LVOT, located below the noncoronary cusp and extending from the annular region, is predictive of aortic root injury during TAVR with a balloon-expandable valve.


Asunto(s)
Enfermedades de la Aorta/complicaciones , Estenosis de la Válvula Aórtica/terapia , Válvula Aórtica/patología , Calcinosis/terapia , Cateterismo Cardíaco/efectos adversos , Lesiones Cardíacas/etiología , Implantación de Prótesis de Válvulas Cardíacas/efectos adversos , Cifoplastia/efectos adversos , Calcificación Vascular/complicaciones , Lesiones del Sistema Vascular/etiología , Anciano , Anciano de 80 o más Años , Enfermedades de la Aorta/diagnóstico , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/lesiones , Estenosis de la Válvula Aórtica/complicaciones , Estenosis de la Válvula Aórtica/diagnóstico , Aortografía/métodos , Calcinosis/complicaciones , Calcinosis/diagnóstico , Cateterismo Cardíaco/métodos , Estudios de Casos y Controles , Femenino , Lesiones Cardíacas/diagnóstico , Implantación de Prótesis de Válvulas Cardíacas/métodos , Humanos , Masculino , Tomografía Computarizada Multidetector , Valor Predictivo de las Pruebas , Medición de Riesgo , Factores de Riesgo , Índice de Severidad de la Enfermedad , Resultado del Tratamiento , Calcificación Vascular/diagnóstico , Lesiones del Sistema Vascular/diagnóstico
19.
J Am Coll Cardiol ; 63(10): 976-81, 2014 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-24211502

RESUMEN

OBJECTIVES: This study sought to assess the clinical outcomes and hemodynamic performance associated with a strategy of underexpanding balloon-expandable transcatheter heart valves (THV) when excessive oversizing is a concern. BACKGROUND: Transcatheter aortic valve replacement depends on the selection of an optimally sized THV. An undersized THV may lead to paravalvular regurgitation, whereas excessive oversizing may lead to annular injury. METHODS: Patients (n = 47) who underwent transcatheter aortic valve replacement with an intentionally underexpanded THV (balloon-filling volume reduced ~10%) were compared with consecutive control patients who had nominal THV balloon deployment (n = 87). Pre- and post-procedural computed tomography imaging and echocardiography were performed to assess THV stent expansion and hemodynamics. RESULTS: Underfilling resulted in THV underexpansion that was maximal at the THV inflow (85.0 ± 7.4% vs. 102.5 ± 6.2%, p < 0.001), in study versus control groups, respectively. The study group received larger THV, although annular injury was not observed. Post-dilation was required in 10.6% and 4.6% of patients of the study and control groups, respectively (p = 0.165). Echocardiographic THV area, gradient, paravalvular regurgitation, and in-hospital outcomes were similar. CONCLUSIONS: Intentionally underexpanding balloon-expandable THV by underfilling the deployment balloon did not adversely affect procedural clinical outcomes, THV gradients, or THV areas. A strategy of underexpansion, with post-dilation as necessary, might play in role in reducing the risk of annular injury and paravalvular regurgitation in selected patients.


Asunto(s)
Estenosis de la Válvula Aórtica/cirugía , Cateterismo Cardíaco/métodos , Implantación de Prótesis de Válvulas Cardíacas/métodos , Selección de Paciente , Anciano de 80 o más Años , Estenosis de la Válvula Aórtica/diagnóstico , Ecocardiografía Transesofágica , Femenino , Estudios de Seguimiento , Humanos , Masculino , Tomografía Computarizada Multidetector , Diseño de Prótesis , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
20.
J Cardiovasc Comput Tomogr ; 7(4): 248-55, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24148778

RESUMEN

BACKGROUND: Prosthesis-patient mismatch (PPM) is a predictor of mortality after aortic valve replacement (AVR). OBJECTIVE: We examined whether accurate 3-dimensional annular sizing with multidetector CT (MDCT) is predictive of PPM after transcatheter AVR (TAVR). METHODS: One hundred twenty-eight patients underwent MDCT then TAVR. Moderate PPM was defined as an indexed effective orifice area ≤0.85 cm²/m² and severe ≤0.65 cm²/m². MDCT annular measurements (area, short and long axis) were compared with the size of the selected transcatheter heart valve (THV) to obtain (1) the difference between prosthesis size and CT-measured mean annular diameter and (2) the percentage of undersizing or oversizing (calculated as 100 × [MDCT annular area--THV nominal area]/THV nominal area). In addition, the MDCT annular area was indexed to body surface area. These measures were evaluated as potential PPM predictors. RESULTS: We found that 42.2% of patients had moderate PPM and 9.4% had severe PPM. Procedural characteristics and in-hospital outcomes were similar between patients with or without PPM. THV undersizing of the mean aortic annulus diameter was not predictive of PPM (odds ratio [OR], 0.84; 95% CI, 0.65-1.07; P = .16; area under the receiver-operating characteristic curve [AUC], 0.58). THV undersizing of annular area was not predictive of PPM (OR, 0.96; 95% CI, 0.80-1.16; P = .69; AUC, 0.52). Indexed MDCT annular area was, however, predictive of PPM (OR, 0.24; 95% CI, 0.10-0.59; P < .001; AUC, 0.66). CONCLUSIONS: PPM is frequent after TAVR. Appropriate annular oversizing does not reduce the rate or severity of PPM. Patient annulus size mismatch, identified by indexed MDCT annular area, is a significant predictor of PPM.


Asunto(s)
Estenosis de la Válvula Aórtica/diagnóstico por imagen , Estenosis de la Válvula Aórtica/terapia , Válvula Aórtica/diagnóstico por imagen , Cateterismo Cardíaco/instrumentación , Implantación de Prótesis de Válvulas Cardíacas/instrumentación , Prótesis Valvulares Cardíacas , Tomografía Computarizada Multidetector , Anciano , Anciano de 80 o más Años , Área Bajo la Curva , Colombia Británica , Cateterismo Cardíaco/efectos adversos , Distribución de Chi-Cuadrado , Dinamarca , Ecocardiografía Transesofágica , Femenino , Implantación de Prótesis de Válvulas Cardíacas/efectos adversos , Implantación de Prótesis de Válvulas Cardíacas/métodos , Humanos , Imagenología Tridimensional , Modelos Logísticos , Masculino , Oportunidad Relativa , Valor Predictivo de las Pruebas , Diseño de Prótesis , Curva ROC , Interpretación de Imagen Radiográfica Asistida por Computador , Factores de Riesgo , Resultado del Tratamiento
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