Safety and Pharmacokinetics of a Combined Antioxidant Therapy against Myocardial Reperfusion Injury: A Phase 1 Randomized Clinical Trial in Healthy Humans.

Myocardial reperfusion injury (MRI) accounts for up to 50% of the final size in acute myocardial infarction and other conditions associated with ischemia-reperfusion. Currently, there is still no therapy to prevent MRI, but it is well known that oxidative stress has a key role in its mechanism. We previously reduced MRI in rats through a combined antioxidant therapy (CAT) of ascorbic acid, N-acetylcysteine, and deferoxamine. This study determines the safety and pharmacokinetics of CAT in a Phase I clinical trial. Healthy subjects (n = 18) were randomized 2:1 to CAT or placebo (NaCl 0.9% i.v.). Two different doses/infusion rates of CATs were tested in a single 90-minute intravenous infusion. Blood samples were collected at specific times for 180 minutes to measure plasma drug concentrations (ascorbic acid, N-acetylcysteine, and deferoxamine) and oxidative stress biomarkers. Adverse events were registered during infusion and followed for 30 days. Both CAT1 and CAT2 significantly increased the CAT drug concentrations compared to placebo (P < .05). Most of the pharmacokinetic parameters were similar between CAT1 and CAT2. In total, 6 adverse events were reported, all nonserious and observed in CAT1. The ferric-reducing ability of plasma (an antioxidant biomarker) increased in both CAT groups compared to placebo (P < .001). The CAT is safe in humans and a potential treatment for patients with acute myocardial infarction undergoing reperfusion therapy.

Registro multicéntrico impella CP para shock cardiogénico o angioplastía de alto riesgo protegida en Chile / Use of impella CP in high risk coronary angioplasty and cardiogenic shock: a registry

Antecedentes: El Shock Cardiogénico (SC) y las Angioplastías de Alto Riesgo (AAR) están asociadas con altas tasas de mortalidad. El uso del dispositivo Impella CP podría reducir el riesgo de muerte en estos escenarios. En Chile no existen reportes evaluando el uso del dispositivo Impella CP. Objetivo: Analizar los desenlaces clínicos en pacientes que fueron sometidos al uso del dispositivo Impella CP por SC o por AAR. Métodos: Se realizó un estudio retrospectivo en 17 pacientes, los cuales representan el total de implantes realizados en el país, entre octubre 2021 y agosto 2023. Se describió las características, demográficas, procedimentales y después del implante. Se estimó la mortalidad general y se identificaron factores asociados. Resultados: La edad de los pacientes fue 69± 3,7 años y 88,2% fueron hombres. El 64,7% recibió el dispositivo por SC y 35,3% por AAR. Dentro de las comorbilidades estudiadas, la hipertensión arterial fue la más frecuente, 94,1%. Un 58,8% de los pacientes fueron revascularizados a través de la arteria radial. El 29,4% recibió el dispositivo previo a la angioplastía y 70,6% lo recibió después. El 47,1% de las angioplastías fue guiada por imágenes. En 11,8% de ellos se realizó litotricia intracoronaria y 5,9% por ablación intracoronaria. Los pacientes estuvieron 13 ±3,4 días con el soporte. La mortalidad global fue de 41,2%. Conclusiones: El uso del dispositivo Impella presentó pocas complicaciones vasculares. La mortalidad asociada con su colocación en Chile fue relativamente similar con la reportada en la literatura.

Background: Cardiogenic shock and high-risk Angioplasty are associated with a high mortality rate. Using the Impella CP device could reduce the risk of death in these scenarios. In Chile, there are no studies evaluating the use of the Impella CP device. Objective: To analyse the clinical outcomes in patients who have undergone placement of the Impella CP device for cardiogenic shock and high-risk angioplasties. Methods: A retrospective study was carried out on 17 patients, which represent the total number of implants performed in the country, between October 2021 and August 2023. The demographic, procedural and post-implant characteristics were described. Overall mortality and associated factors were identified. Results: The age was 69± 3.7 years, where 88.2% were men. 64.7% of patients received the device by SC and 35.3% by AAR. Among the comorbidities studied, arterial hypertension was the most frequent with 94.1%. 58.8% of patients were revascularized through the radial artery. 29.4% of patients received the device before angioplasty and 70.6% received it afterwards. 47.1% of angioplasties were image-guided, 11.8% had intracoronary lithotripsy, and 5.9% had intracoronary ablation. The patients spent 13 ±3.4 days with the support. Overall mortality was 41.2%. Conclusion: use of the Impella device was associated with few vascular complications. Mortality associated with use of the Impella device in Chile was similar to that previously reported in other studies.

Uso de anticoagulantes orales directos en pacientes con fibrilación auricular post implante de TAVI: resultados de una encuesta internacional / Use of anticoagulants in patients with atrial fibrillation undergoing transcatheter aortic valve implantation

BACKGROUND: Transcatheter Aortic Valve Implantation (TAVI) is beneficial in patients with symptomatic severe Aortic Stenosis (AS). There is no consensus about the best anticoagulation strategy for patients with a recent TAVI and with atrial fibrillation (AF). Direct oral anticoagulants (DOACs) are effective to prevent embolic events with a significant lower incidence of bleeding. There is scarce evidence about the use of these drugs in patients undergoing TAVI. AIM: To assess the management of anticoagulation at the moment of discharge of patients with AF and TAVI. Material and Methods: A four question survey was sent to cardiologists involved in TAVI programs in different international centers. Results: The survey was answered by 72 interventional cardiologists. Even with the lack of randomized evidence, in most of the scenarios DOACs are prescribed at discharge in patients with indication for anticoagulation. Also, in patients with high bleeding risk, most cardiologists would perform a left atrial appendage closure. In patients with concomitant coronary artery disease, if a stent was recently implanted, prescription of the combination of a DOAC and one antiplatelet drug was the most common answer. In patients with a former coronary angioplasty, DOAC or Warfarin was the therapy of choice. CONCLUSIONS: In the absence of randomized data, interventional cardiologists prescribe DOACs at discharge to patients with AF and TAVI, without following current guidelines in most cases.

PRospective Observational Registry Evaluating the Safety and Effectivenessof Orsiro Stent in Chilean Patients - ROSES Registry.

BACKGROUND: There is little information on the performance of the new generation of stents with bioabsorbable polymers in the Latin American population. This registry aimed to further validate the safety and efficacy of the Orsiro bioresorbable-polymer sirolimus-eluting stent (BPSES) in unselected patients undergoing percutaneous coronary intervention (PCI) in Chilean centers. METHODS: We prospectively enrolled patients undergoing PCI with BPSES in 6 Chilean centers. The primary endpoint was defined as the composite of cardiac death, target vessel-related myocardial infarction (MI), and clinically driven target lesion revascularization at 1-year follow-up. RESULTS: From April 2017 to February 2019, 520 patients were enrolled in the registry, more frequently male (74.6%), with a mean age of 62.7 ± 10.8 years and a high prevalence of diabetes (40.2%). The clinical presentation was stable angina in 41.1% (n = 214), acute MI in 52.5% (n = 167 [32.1%] ST-elevation MI and n = 106 [20.4%] non-ST-elevation MI), and unstable angina in 6.3% (n = 33). Of 610 treated lesions, 425 (69.7%) were American College of Cardiology/American Heart Association type B or C lesions. Device and procedural success were achieved in 99.4% and 98.7% of the patients, respectively. The primary endpoint of the study occurred in 4%, primarily driven by cardiac death. CONCLUSIONS: The results of the ROSES multicenter registry indicated good clinical outcomes of BPSES Orsiro in all-comers Latin Americann patients undergoing PCI, despite the high-risk patients and treated lesions.

[Use of anticoagulants in patients with atrial fibrillation undergoing transcatheter aortic valve implantation]. / Uso de anticoagulantes orales directos en pacientes con fibrilación auricular post implante de TAVI: resultados de una encuesta internacional.

BACKGROUND: Transcatheter Aortic Valve Implantation (TAVI) is beneficial in patients with symptomatic severe Aortic Stenosis (AS). There is no consensus about the best anticoagulation strategy for patients with a recent TAVI and with atrial fibrillation (AF). Direct oral anticoagulants (DOACs) are effective to prevent embolic events with a significant lower incidence of bleeding. There is scarce evidence about the use of these drugs in patients undergoing TAVI. AIM: To assess the management of anticoagulation at the moment of discharge of patients with AF and TAVI. MATERIAL AND METHODS: A four question survey was sent to cardiologists involved in TAVI programs in different international centers. RESULTS: The survey was answered by 72 interventional cardiologists. Even with the lack of randomized evidence, in most of the scenarios DOACs are prescribed at discharge in patients with indication for anticoagulation. Also, in patients with high bleeding risk, most cardiologists would perform a left atrial appendage closure. In patients with concomitant coronary artery disease, if a stent was recently implanted, prescription of the combination of a DOAC and one antiplatelet drug was the most common answer. In patients with a former coronary angioplasty, DOAC or Warfarin was the therapy of choice. CONCLUSIONS: In the absence of randomized data, interventional cardiologists prescribe DOACs at discharge to patients with AF and TAVI, without following current guidelines in most cases.

Joint Cardioprotective Effect of Vitamin C and Other Antioxidants against Reperfusion Injury in Patients with Acute Myocardial Infarction Undergoing Percutaneous Coronary Intervention.

Percutaneous coronary intervention (PCI) has long remained the gold standard therapy to restore coronary blood flow after acute myocardial infarction (AMI). However, this procedure leads to the development of increased production of reactive oxygen species (ROS) that can exacerbate the damage caused by AMI, particularly during the reperfusion phase. Numerous attempts based on antioxidant treatments, aimed to reduce the oxidative injury of cardiac tissue, have failed in achieving an effective therapy for these patients. Among these studies, results derived from the use of vitamin C (Vit C) have been inconclusive so far, likely due to suboptimal study designs, misinterpretations, and the erroneous conclusions of clinical trials. Nevertheless, recent clinical trials have shown that the intravenous infusion of Vit C prior to PCI-reduced cardiac injury biomarkers, as well as inflammatory biomarkers and ROS production. In addition, improvements of functional parameters, such as left ventricular ejection fraction (LVEF) and telediastolic left ventricular volume, showed a trend but had an inconclusive association with Vit C. Therefore, it seems reasonable that these beneficial effects could be further enhanced by the association with other antioxidant agents. Indeed, the complexity and the multifactorial nature of the mechanism of injury occurring in AMI demands multitarget agents to reach an enhancement of the expected cardioprotection, a paradigm needing to be demonstrated. The present review provides data supporting the view that an intravenous infusion containing combined safe antioxidants could be a suitable strategy to reduce cardiac injury, thus improving the clinical outcome, life quality, and life expectancy of patients subjected to PCI following AMI.

Repercusión de la pandemia COVID-19 en la práctica de la cardiología intervencional en Chile: datos aportados por la encuesta del grupo Stent-Save a Life! LATAM working group / Decrease in the activity of interventional cardiology in Chile: a report from the "Stent-Save a Life! LATAM working group"

RESUMEN: Introducción: El Stent-Save a Life! (SSL) LATAM working group diseñó una encuesta para objetivar la reducción de la actividad de los laboratorios de hemodinamia en Latinoamérica durante la pandemia COVID-19. Ante la amenaza de nuevos confinamientos en Chile, nos propusimos objetivar las consecuencias de la primera ola de contagios en nuestra actividad. Objetivos: Discutir la repercusión de la pandemia en la cardiología intervencional en Chile. Métodos: El grupo SSL realizó una encuesta telemática a todos los países de Latinoamérica incluido Chile. Se registraron las coronariografías (CAG), intervenciones coronarias percutáneas (ACTP) e intervenciones estructurales, comparando dos períodos determinados por el confinamiento por la pandemia, cada uno de dos semanas. Pre-COVID-19: período previo al confinamiento, y COVID-19: período durante el confinamiento. Se analizan, a partir de esta encuesta, los resultados aplicados a nuestro país. Resultados: Se obtuvo respuesta de trece centros. Hubo una reducción en el número global de procedimientos entre período Pre-COVID-19 y COVID-19 de un 65,1%. Se reportó una disminución de 67% en las CAG, de un 59,4% en las ACTP y de un 92% en los procedimientos terapéuticos estructurales. Entre ambos períodos se redujo la consulta por Síndrome Coronario Agudo por elevación del segmento ST (SCACEST) en 40,8%. Conclusiones: En nuestro país se objetivó una reducción marcada de la actividad asistencial de la cardiología intervencional durante la pandemia COVID-19 y una disminución significativa en el número de pacientes tratados por SCACEST. Los resultados de nuestro país son similares a los reportados por países de Latinoamérica, Europa y Norteamérica.

ABSTRACT: Background: The Stent-Save a Life! (SSL) LATAM working group designed a survey to demonstrate the reduction in the activity of cardiac catheterization laboratories in Latin America during the COVID-19 pandemic. Considering the risk of a new confinement in Chile, we decided to assess the impact of the first wave of contagions on our activity. Aims: To discuss the repercussion of the COVID-19 pandemic on the activity of interventional cardiology in Chile. Methods: The SSL group conducted a telematic survey in all Latin American countries. Coronary angiography, coronary interventions (PCI) and structural interventions were registered, comparing two periods of two weeks duration each: before and during COVID-19 confinement. Results obtained in Chile are analyzed. Results: Thirteen centers in Chile answered the survey. There was an overall decrease of 65.1% in the number of procedures between the pre and the post COVID-19 periods. Coronary angiographies decreased 67%, PCI 59.4% and therapeutical structural procedures 92%. The reduction in acute coronary syndrome with ST segment elevation (STEMI) was 40,8% between periods. Conclusions: In Chile, a significant reduction in healthcare activity related to interventional cardiology and a significant decrease in the number of patients treated with STEMI was observed during the COVID-19 pandemic. The results are similar to those reported by Latin American, European and North American countries.

[Percutaneous implantation of an aortic prosthetic valve on a degenerated mitral bioprosthesis. Report of one case]. / Implantación percutánea transeptal de válvula protésica aórtica sobre bioprótesis mitral degenerada.

Reintervention of a mitral degenerated bioprosthesis has a high surgical risk, especially in elderly patients with multiple comorbidities. We report a 74 years old female with two previous cardiac surgical procedures and a new structural mitral bioprosthesis deterioration with severe mitral regurgitation. Considering her high-surgical risk, a fully percutaneous treatment was performed with a balloon-expandable aortic valve in mitral position (valve-in-valve) through a transseptal approach with a favorable outcome. This technique is an attractive and effective option with a relatively low rate of complications that could solve this challenging and complex disease.

Implantación percutánea transeptal de válvula protésica aórtica sobre bioprótesis mitral degenerada / Percutaneous implantation of an aortic prosthetic valve on a degenerated mitral bioprosthesis. Report of one case

Reintervention of a mitral degenerated bioprosthesis has a high surgical risk, especially in elderly patients with multiple comorbidities. We report a 74 years old female with two previous cardiac surgical procedures and a new structural mitral bioprosthesis deterioration with severe mitral regurgitation. Considering her high-surgical risk, a fully percutaneous treatment was performed with a balloon-expandable aortic valve in mitral position (valve-in-valve) through a transseptal approach with a favorable outcome. This technique is an attractive and effective option with a relatively low rate of complications that could solve this challenging and complex disease.

[Balloon pulmonary angioplasty for the treatment of chronic thromboembolic pulmonary hypertension]. / Angioplastía con balón para el tratamiento de la hipertensión arterial pulmonar por enfermedad tromboembólica crónica. Resultados hemodinámicos y clínicos inmediatos.

BACKGROUND: Balloon pulmonary angioplasty (BPA) is a therapeutic alternative for patients with inoperable chronic thromboembolic pulmonary hypertension (CTEPH). AIM: To report the initial experience with the "refined BPA technique" with the use of intravascular images. PATIENTS AND METHODS: Between June 2015 and June 2016 we selected fourteen patients with CTEPH who were considered candidates for BPA. Lesions targeted for treatment were further analyzed using intravascular imaging with optical frequency domain imaging (OFDI). We report the immediate hemodynamic results and four weeks of follow-up of the first eight patients of this series. RESULTS: We performed 16 BPA in eight patients aged 61 ± 14 years (88% women). Mean pulmonary artery pressure (PAPm) was 48.6 ± 5.8 mmHg. Success was achieved in seven patients (88%). A mean of 2.3 segments per patient were intervened in 11 sessions (1.6 sessions/ patient). Only one patient developed lung reperfusion injury. No mortality was associated with the procedure. After the last BPA session, PAPm decreased to 37.4 ± 8.6 mmHg (p=0.02). Pulmonary vascular resistance (RVP) decreased from 858,6 ± 377,0 at baseline to 516,6 ± 323,3 Dynes/sec/cm-5 (p<0.01) and the cardiac index increased from 2.4±0.6 at baseline to 2.8±0.3 L/min/m2 (p=0.01). At 4 weeks after the last BPA, WHO functional class improved from 3.3±0.5 to 2.5±0.5 (p<0,01) and six minutes walking distance from 331±92 to 451±149 m (p=0.01). CONCLUSIONS: BPA guided by OFDI for the treatment of inoperable CTEPH patients is a safe alternative with excellent immediate hemodynamic and clinical results.

Angioplastía con balón para el tratamiento de la hipertensión arterial pulmonar por enfermedad tromboembólica crónica. Resultados hemodinámicos y clínicos inmediatos / Balloon pulmonary angioplasty for the treatment of chronic thromboembolic pulmonary hypertension

Background: Balloon pulmonary angioplasty (BPA) is a therapeutic alternative for patients with inoperable chronic thromboembolic pulmonary hypertension (CTEPH). Aim: To report the initial experience with the "refined BPA technique" with the use of intravascular images. Patients and Methods: Between June 2015 and June 2016 we selected fourteen patients with CTEPH who were considered candidates for BPA. Lesions targeted for treatment were further analyzed using intravascular imaging with optical frequency domain imaging (OFDI). We report the immediate hemodynamic results and four weeks of follow-up of the first eight patients of this series. Results: We performed 16 BPA in eight patients aged 61 ± 14 years (88% women). Mean pulmonary artery pressure (PAPm) was 48.6 ± 5.8 mmHg. Success was achieved in seven patients (88%). A mean of 2.3 segments per patient were intervened in 11 sessions (1.6 sessions/ patient). Only one patient developed lung reperfusion injury. No mortality was associated with the procedure. After the last BPA session, PAPm decreased to 37.4 ± 8.6 mmHg (p=0.02). Pulmonary vascular resistance (RVP) decreased from 858,6 ± 377,0 at baseline to 516,6 ± 323,3 Dynes/sec/cm−5 (p<0.01) and the cardiac index increased from 2.4±0.6 at baseline to 2.8±0.3 L/min/m2 (p=0.01). At 4 weeks after the last BPA, WHO functional class improved from 3.3±0.5 to 2.5±0.5 (p<0,01) and six minutes walking distance from 331±92 to 451±149 m (p=0.01). Conclusions: BPA guided by OFDI for the treatment of inoperable CTEPH patients is a safe alternative with excellent immediate hemodynamic and clinical results.

Effects of a novel ascorbate-based protocol on infarct size and ventricle function in acute myocardial infarction patients undergoing percutaneous coronary angioplasty.

INTRODUCTION: This study was designed to test the hypothesis that high-dose ascorbate prior to reperfusion followed by low chronic oral doses ameliorate myocardial reperfusion injury (MRI) in acute myocardial infarction patients subjected to primary percutaneous coronary angioplasty (PCA). MATERIAL AND METHODS: A randomized double-blind placebo-controlled and multicenter clinical trial was performed on acute myocardial infarction (AMI) patients who underwent PCA. Sodium ascorbate (320 mmol/l, n = 53) or placebo (n = 46) was infused 30 min prior to PCA. Blood samples were drawn at enrolment (M1), after balloon deflation (M2), 6-8 h after M2 (M3) and at discharge (M4). Total antioxidant capacity of plasma (ferric reducing ability of plasma - FRAP), erythrocyte reduced glutathione (GSH) and plasma ascorbate levels were determined in blood samples. Cardiac magnetic resonance (CMR) was performed at 7-15 days and 2-3 months following PCA. Ninety-nine patients were enrolled. In 67 patients, the first CMR was performed, and 40 patients completed follow-up. RESULTS: The ascorbate group showed significantly higher ascorbate and FRAP levels and a decrease in the GSH levels at M2 and M3 (p < 0.05). There were no significant differences in the infarct size, indexed end-systolic volume and ejection fraction at both CMRs. There was a significant amelioration in the decreased ejection fraction between the first and second CMR in the ascorbate group (p < 0.05). CONCLUSIONS: Ascorbate given prior to reperfusion did not show a significant difference in infarct size or ejection fraction. However, it improved the change in ejection fraction determined between 7-15 days and 2-3 months. This result hints at a possible functional effect of ascorbate to ameliorate MRI.

Amelioration of persistent left ventricular function impairment through increased plasma ascorbate levels following myocardial infarction.

PURPOSE: Percutaneous coronary angioplasty (PCA) has been demonstrated to reduce mortality and morbidity and thereby improve the prognosis of patients undergoing acute myocardial infarctions (AMIs). However, this procedure paradoxically increases the initial damage as the result of a condition known as 'myocardial reperfusion injury'. Oxidative stress may contribute to the mechanism of this injury. The goal of the present study was to ascertain whether high plasma ascorbate levels could ameliorate the reperfusion injuries that occur after the successful restoration of blood flow. METHODS: Patients from three clinical centers of the public health system were included in the study. The groups were formed by either-sex patients with a diagnosis of ST-segment elevation myocardial infarction with an indication for primary PCA. Only the patients who presented with their first myocardial infarction were enrolled. Ascorbate was administered through an infusion given prior to the restoration of the coronary flow, which was then followed by oral treatment with vitamin C (500 mg/12 hours) plus vitamin E (400 IU/day) for 84 days. The left ventricular ejection fraction (LVEF) was determined by using cardiac magnetic resonance on days 6 and 84 following the onset of the reperfusion. In addition, the microvascular function was assessed by an angiographic evaluation using the Thrombolysis In Myocardial Infarction (TIMI) myocardial perfusion grade (TMPG). The results were grouped according to the plasma ascorbate concentration achieved immediately following the onset of reperfusion into either the HA group (high ascorbate, >1 mmol/l) or the LA group (low ascorbate, <1 mmol/l). The biochemical parameters were analyzed throughout the protocol. RESULTS: The LVEF of the HA group was significantly higher than that of the LA group, values on day 84 in the HA group were 33% higher than those of the LA group. The amelioration of the LVEF was accompanied by an improvement in the microvascular dysfunction, after PCA, 95% of the patients in the HA group achieved a TMPG of 2-3, in the LA group only 79% of patients showed a TMPG of 2-3. CONCLUSIONS: These data are consistent with the protective effect of high plasma levels of ascorbate against the oxidative challenge caused by reperfusion injury in patients subjected to PCA following an AMI. Further studies are needed to elucidate the mechanism accounting for this beneficial antioxidant effect.

Valvuloplastía mitral percutánea: experiencia del Hospital San Juan de Dios / Percutaneous mitral valvuloplasty: the San Juan de Dios Hospital experience

Objetivo: Evaluar los resultados alejados de la valvuloplastía mitral percutánea (VMP), y analizar los factores asociados con eventos y reestenosis tardía. Métodos y resultados: De 252 VPM realizadas entre diciembre de 1987 y diciembre de 2006, 245 pacientes tuvieron un mínimo de 6 meses de seguimiento y evaluación ecocardiográfica antes y después del procedimiento (97 por ciento). La edad media fue de 46,3 +/- 11,37 años, las mujeres fueron 83,6 por ciento. La media de seguimiento fue de 35,25 +/- 28,84 meses, rango 6-132. La muerte cardiovascular, y el reemplazo de la válvula mitral o una segunda VMP fueron considerados como marcadores de peor resultado. El área de la válvula mitral aumentó de 1,0 +/- 0,17 cm2 a 1,71 +/- 0,31 cm2 (p <0,0001) después del procedimiento. Durante el seguimiento, 53 pacientes (21,6 por ciento) presentaron reestenosis, que fue predicha por un Score de Wilkins > 8 (p = 0,03). Cinco pacientes fallecieron (2,04 por ciento), 22 (8,9 por ciento) requirieron reemplazo de la válvula mitral y 11 (4,5 por ciento) una segunda VMP. No encontramos variables clínicas o ecocardiográficas capaces de predecir estos eventos. Conclusiones La VMP tuvo una tasa aceptable de complicaciones atribuibles al procedimiento. Las características ecocardiográficas de la válvula mitral se correlacionaron con la reestenosis. La incidencia de eventos tardíos es baja.

Objective: To evalúate the long-term results of percutaneous mitral valvuloplasty (PMV), and analyze the factors associated with restenosis and late events. Methods and results: Of 252 PMV performed between December 1987 and December 2006, 245 patients with a minimum of 6 months follow-up and echocardiographic evaluation before and after the procedure, were selected for long-term follow-up (97 percent). The mean age was 46.3 +/- 11.37 years old, 83.6 percent women. The mean follow-up was 35.25 +/- 28.84 months, range 6-132. Cardiovascular death, and mitral valve replacement or second PMV, were considered as markers of worst outcome. The mitral valve area increased from 1.0+/-0.17cm2 to 1.71 +/- 0.31 cm2 (p <0.0001) after the first procedure. During follow up, 53 patients (21.6 percent) developed restenosis, which was predicted by a Wilkins score > 8 (p = 0.03). Five (2.04 percent) patients died. Twenty-two (8.9 percent) required mitral valve replacement and 11(4.5 percent) a second PMV. We found that no clinical or echocardiographic variables were able to predict these events. Conclusions: PMV had an acceptable rate of complications attributable to the procedure. The echocardiographic characteristics of the mitral valve correlated with restenosis. The incidence of late events is low.

Enfermedad de Bartter: ¿por qué se disnutren? / Bartter's disease: why do they get undernourished?

Se presentan los resultados de balances metabólicos llevados a cabo en tres lactantes portadores de enfermedad de Bartter, en los que resaltaron tanto una baja ingesta como una pérdida nitrogenada exagerada. A la luz de estos antecedentes se plantea una hipótesis acerca de la génesis de la acentuada desnutrición y retardo de crecimiento, de estos niños, basada en hechos fisiológicos previamente comprobados