Pseudoquiste de páncreas y hernia interna complicada. Presentación de un caso

Las hernias internas en su mayoría son de causas congénitas. Constituyen entidades nosológicas poco frecuentes. El cuadro abdominal agudo secundario a la complicación de estas se relaciona con oclusión intestinal y necrosis. En ocasiones, algunas enfermedades que anteceden o se descubren en el transcurso del padecimiento clínico, como el pseudoquiste pancreático, pueden dificultar el diagnóstico positivo. En este informe se describe el caso clínico de un paciente con diagnóstico de pseudoquiste de páncreas, que en el transcurso de la enfermedad presentó complicación de hernia interna. El paciente, de 45 años y con diagnóstico de pseudoquiste pancreático, presentó durante su ingreso cuadro de dolor abdominal acompañado de vómitos, lo que dio lugar a la sospecha de ruptura del pseudoquiste. Fue operado de urgencia, y se obtuvo entonces la evidencia de hernia interna (no diagnosticada de forma preoperatoria) complicada con necrosis de segmento de intestino delgado. No se observó ruptura del pseudoquiste pancreático. Las manifestaciones clínicas de la hernia interna complicada y la ruptura del pseudoquiste de páncreas son difíciles de discernir entre sí. El tratamiento quirúrgico de urgencia es el pilar fundamental ante la duda diagnóstica o el empeoramiento clínico del paciente.

Internal hernias are mostly congenital causes. They constitute rare nosological entities. The acute abdominal picture secondary to the complication of these is related to intestinal occlusion and necrosis. Sometimes, some diseases that precede or are discovered during the clinical condition, such as pancreatic pseudocyst, can make a positive diagnosis difficult. The clinical case of a patient diagnosed with a pancreatic pseudocyst, who presented a complication of internal hernia during the course of the disease it is described in this report. The 45-years-old patient with a pancreatic pseudocyst diagnosis presented symptoms of abdominal pain accompanied by vomiting during his admission, which led to suspicion of rupture of the pseudocyst. He underwent emergency surgery, and evidence of an internal hernia (not diagnosed preoperatively) complicated with small bowel segment necrosis was then obtained. No rupture of the pancreatic pseudocyst was observed. The clinical manifestations of complicated internal hernia and pancreatic pseudocyst rupture are difficult to distinguish from each other. Emergency surgical treatment is the fundamental pillar in the face of diagnostic doubt or clinical worsening of the patient.

Programa para mejorar la recuperación posoperatoria en intervenciones electivas de colon / A Program for Improving Postoperative Recovery in Elective Colon Surgeries

Introducción: Los programas de recuperación mejorada después de cirugía constituyen un conjunto de acciones aplicadas al paciente quirúrgico en el período perioperatorio, que se enfoca en reducir el impacto de la cirugía en la respuesta metabólica y endocrina y así lograr una recuperación más temprana de mayor calidad. Objetivo: Evaluar los resultados de la aplicación del protocolo de recuperación mejorada después de la cirugía en procedimientos quirúrgicos mayores electivos del colon. Métodos: Se realizó un estudio descriptivo longitudinal y prospectivo con 163 pacientes con indicación de intervenciones quirúrgicas mayores electivas del colon en el Hospital Clínico Quirúrgico "Hermanos Ameijeiras", durante el período 2017-2020 y se les aplicó el programa ERAS implementado. Resultados: La edad media de los pacientes fue de 65,4±13,2 años con predominio del sexo femenino (57,7 por ciento). El 78,5 por ciento de los pacientes toleraban dieta blanda y expulsaban gases o heces por el recto al segundo día de la operación. La estadía posoperatoria promedio fue de 4,9 ± 3,4 días y en pacientes sin complicaciones se redujo a 4,0±1,0 días. La mortalidad reportada fue de un 3,1 por ciento (5 casos). Se complicó el 20,2 por ciento de los pacientes. El 6,7 por ciento de los pacientes requirió reingreso durante los primeros 30 días. Conclusiones: La implementación de un programa para mejorar la recuperación posoperatoria de pacientes con intervenciones electivas de colon demuestra resultados satisfactorios y mejora los resultados históricos del Hospital Clínico Quirúrgico "Hermanos Ameijeiras", en cuanto a complicaciones, estadía y mortalidad(AU)

Introduction: Enhanced recovery after surgery (ERAS) programs are a set of actions applied to the surgical patient in the perioperative period, focusing on reducing the impact of surgery on the metabolic and endocrine response, with the aim of achieving an earlier recovery of higher quality. Objective: To evaluate the results of the application of the enhanced recovery protocol after surgery in elective major surgical procedures of the colon. Methods: A descriptive, longitudinal and prospective study was conducted with 163 patients indicated for elective major surgery of the colon at Hospital Clínico Quirúrgico "Hermanos Ameijeiras", during the period 2017-2020, and who were applied the implemented ERAS program. Results: The mean age of the patients was 65.4 ± 13.2 years, with a predominance of the female sex (57.7 percent). 78.5 the patients tolerated a soft diet and expelled gases or faces througth the rectum at two days after the operation. The average postoperative stay was 4.9 ± 3.4 days and, in patients without complications, it was reduced to 4.0 ± 1.0 days. Reported mortality was 3.1 percent (five cases). Complications occurred in 20.2 percent of the patients. 6.7 percent of patients required readmission during the first thirty days. Conclusions: The implementation of a program for improving postoperative recovery of patients with elective interventions of the colon shows satisfactory results and improves the historical results of Hospital Clínico Quirúrgico "Hermanos Ameijeiras" in terms of complications, length of stay and mortality(AU)

Síndrome de Mirizzi grado IV. Presentación de un caso

El Síndrome de Mirizzi es una afección derivada del impacto de un lito en el conducto cístico o infundíbulo de la vesícula biliar. La enfermedad litiásica, crónica y complicada de la vesícula biliar es un factor determinante. Se presenta el caso de un paciente con historia de íctero obstructivo, al cual se le diagnosticó inicialmente tumor periampular. Fue reevaluado y se le realizaron varias pruebas diagnósticas, hasta llegar al diagnóstico de Síndrome de Mirizzi, corroborado en el acto quirúrgico. El SM es una enfermedad rara de la vía biliar cuyo tratamiento es quirúrgico. La vía laparoscópica para la realización de la colecistectomía es la de elección para casos grado I y en casos seleccionados grado II. La colecistectomía y derivación bilioentérica (hepaticoyeyunostomía) conforman el tratamiento para el resto de los casos.

Mirizzi Syndrome is a condition derived from the impact of a stone in the cystic duct or infundibulum of the gallbladder. Chronic and complicated stone disease of the gallbladder is a determining factor. A patient with a history of obstructive jaundice, who was initially diagnosed with a periampullary tumor is presented. He was reassessed and several diagnostic tests were performed, until reaching the diagnosis of Mirizzi Syndrome, corroborated in the surgical act. MS is a rare disease of the bile duct whose treatment is surgical. The laparoscopic approach to perform cholecystectomy is the one of choice for grade I cases and in selected cases grade II. Cholecystectomy and bilioenteric bypass (hepaticojejunostomy) are the treatment for the rest of the cases.

Paciente positiva a la COVID-19 operada de un insulinoma

RESUMEN Introducción: El insulinoma es una neoplasia neuroendocrina considerada una de las más raras. Surge en las células beta de los islotes de Langerhans, produce insulina de forma constante, por lo que provoca hipoglucemia. Su diagnóstico se basa en criterios clínicos, analíticos y pruebas de imagen. El tratamiento curativo es la cirugía, mediante la enucleación del tumor, la pancreatectomía parcial o total o duodenopancreatectomía cefálica. La actual pandemia dio a lugar a nuevos protocolos de actuación, con el fin de adaptar los recursos sanitarios sin comprometer la seguridad de los pacientes y el personal de salud. Objetivo: Presentar un caso clínico de una paciente con diagnóstico de insulinoma, que requirió tratamiento quirúrgico en el curso de la COVID-19. Caso clínico: Paciente femenina de 48 años de edad, con episodios de hipoglucemia intensa y dificultad para seguimiento clínico adecuado. Se le diagnosticó insulinoma y la COVID-19; esta última empeoró la sintomatología, de forma que resultó imposible el adecuado control metabólico. Se decidió tratamiento quirúrgico; se llevó a cabo la enucleación del tumor, sin complicaciones. Conclusiones: La cirugía es el tratamiento definitivo para lograr la curación en el caso de los tumores neuroendocrinos y la COVID-19 empeora el pronóstico. La decisión del tratamiento quirúrgico, debe ser tomada en discusión multidisciplinaria con el fin de evitar complicaciones postoperatorias.

ABSTRACT Introduction: Insulinoma is a neuroendocrine neoplasm considered one of the rarest, it arises in the beta cells of the islets of Langerhans, it produces insulin constantly, thus causing hypoglycemia. Its diagnosis is based on clinical, analytical and imaging criteria. Curative treatment is surgery, through enucleation of the tumor, partial or total pancreatectomy, or cephalic pancreaticoduodenectomy. The current pandemic gave rise to new action protocols, in order to adapt health resources without compromising the safety of patients and health personnel. Objective: To present a clinical case of a patient diagnosed with insulinoma who required surgical treatment in the course of COVID-19. Clinical case: 48-year-old female patient, with episodes of severe hypoglycemia and difficulty in proper clinical follow up. She was diagnosed with insulinoma and COVID-19, the latter worsened the patient's symptoms in such a way that adequate metabolic control was impossible. Surgical treatment was decided. The tumor was enucleated, without complications. Conclusions: Surgery is the definitive treatment to achieve cure in the case of neuroendocrine tumors, COVID-19 worsens the prognosis of patients with this tumor. Therefore, the decision of surgical treatment must be made in a multidisciplinary discussion in order to avoid postoperative complications.

Cáncer gástrico enmascarado por fitobezoar: a propósito de un caso / Gastric cancer masked by phytobezoar: about a case

RESUMEN Introducción: Se define como bezoar al cúmulo de material extraño no digerido que se encuentra en el tubo digestivo de las personas y algunos animales. Por lo general son localizados en el estómago. El tratamiento médico y endoscópico es el de elección, aunque también va a estar determinado por su localización y su causa. El tratamiento quirúrgico se reserva cuando existe alguna complicación o la terapia endoscópica falla. Objetivo: Presentar un caso clínico de una paciente con obstrucción pilórica completa por fitobezoar y tumor del antropíloro. Caso clínico: Paciente femenina de 54 años de edad, con historia de dolor abdominal en epigastrio, pérdida de apetito, astenia y trastornos dispépticos de nueve meses de evolución. Los estudios de imagen informaron la presencia de cuerpos extraños en estómago correspondientes a bezoares. En el transoperatorio se evidencia además tumor en la región antropilórica. Se realizó extracción del bezoar y la gastrectomía subtotal. Conclusiones: La conducta quirúrgica en caso de fitobezoar gástrico va estar determinada por la falla o contraindicación del tratamiento médico y endoscópico.

ABSTRACT Introduction : Bezoar is defined as the accumulation of undigested foreign material found in the digestive tract of people and some animals. They are generally located in the stomach. Medical and endoscopic treatment is the one of choice, although it will also be determined by its location and its cause. Surgical treatment is reserved when there is any complication or endoscopic therapy fails. Objective : To present a clinical case of a patient with complete pyloric obstruction due to phytobezoar and anthropyloric tumor. Case report: A 54-year-old female patient with a history of abdominal pain in the epigastrium, loss of appetite, asthenia and dyspeptic disorders of nine months of evolution. Imaging studies reported the presence of foreign bodies in the stomach corresponding to bezoars. Transoperatively, a tumor is also evidenced in the anthropyloric region. Bezoar extraction and subtotal gastrectomy were performed. Conclusions : The surgical conduct in case of gastric phytobezoar will be determined by the failure or contraindication of medical and endoscopic treatment.

Structure and Properties of Reactively Extruded Opaque Post-Consumer Recycled PET.

The recyclability of opaque PET, which contains TiO2 nanoparticles, has not been as well-studied as that of transparent PET. The objective of this work is to recycle post-consumer opaque PET through reactive extrusion with Joncryl. The effect of the reactive extrusion process on the molecular structure and on the thermal/mechanical/rheological properties of recycling post-consumer opaque PET (r-PET) has been analyzed. A 1% w/w Joncryl addition caused a moderate increase in the molecular weight. A moderate increase in chain length could not explain a decrease in the overall crystallization rate. This result is probably due to the presence of branches interrupting the crystallizable sequences in reactive extruded r-PET (REX-r-PET). A rheological investigation performed by SAOS/LAOS/elongational studies detected important structural modifications in REX-r-PET with respect to linear r-PET or a reference virgin PET. REX-r-PET is characterized by a slow relaxation process with enlarged elastic behaviors that are characteristic of a long-chain branched material. The mechanical properties of REX-r-PET increased because of the addition of the chain extender without a significant loss of elongation at the break. The reactive extrusion process is a suitable way to recycle opaque PET into a material with enhanced rheological properties (thanks to the production of a chain extension and long-chain branches) with mechanical properties that are comparable to those of a typical virgin PET sample.

Thrombus in transit across a patent foramen ovale in a patient with cerebrovascular accidents, pulmonary embolism, and deep vein thrombosis.

The diagnosis of paradoxical emboli remains elusive in many cases. The causal association between the thrombotic source, the intracardiac shunt, and the final emboli location is seldom demonstrated. We present the case of a 42-year-old woman admitted to the hospital with a third stroke. The presence of a thrombus in transit through a patent foramen ovale (PFO), a deep vein thrombosis (DVT), bilateral pulmonary emboli, and an acute cerebral infarct were concurrently documented.

Cirugía mayor abdominal electiva sin descompresión nasogástrica y con apertura precoz de vía oral / Major Elective Abdominal Surgery without Nasogastric Decompression and with Early Opening of the Oral Route

Introducción: La descompresión con sonda nasogástrica y la vía oral cerrada por varios días, ha sido práctica común tras procedimientos quirúrgicos electivos del tracto digestivo. Los programas para mejorar la recuperación posoperatoria (Enhanced Recovery After Surgery), aconsejan cambiar esta práctica. Objetivo: Evaluar el cumplimiento y repercusión en la evolución posoperatoria de dos acciones del programa en el retiro de la sonda nasogástrica y la apertura de la vía oral el día de la intervención. Métodos: Se realizó un estudio prospectivo, en el Servicio de Cirugía General del Hospital "Hermanos Ameijeiras" de septiembre 2017 a agosto 2020. La muestra fue de 270 pacientes con intervención quirúrgica mayor electiva del colon, hígado, vía biliar o páncreas, a los que se les aplicó el programa para mejorar la recuperación posoperatoria. Resultados: En 79,6 por ciento de pacientes, la sonda nasogástrica se retiró en el quirófano tras la intervención y esto se asoció a más rápida recuperación de la función intestinal, menor estadía, complicaciones, reingresos y reintervenciones. En 60 por ciento se inició la vía oral 6 horas después de la cirugía y 79,6 por ciento toleraban dieta blanda a las 48 horas. Estos pacientes presentaron menos complicaciones y mortalidad. Conclusiones: En el contexto de un programa para mejorar la recuperación posoperatoria, tras cirugía abdominal electiva, el retiro de la sonda nasogástrica el día de la intervención, con apertura precoz de la vía oral y rápida progresión a dieta blanda, son acciones bien toleradas que repercuten positivamente en la evolución posoperatoria(AU)

Introduction: Nasogastric tube decompression, together with the oral route closed for several days, has been a common practice after elective surgical procedures of the digestive tract. Programs to improve postoperative recovery (Enhanced Recovery After Surgery) advise changing this practice. Objective: To assess compliance and impact on postoperative evolution of two program actions for nasogastric tube removal and opening of the oral route on the intervention day. Methods: A prospective study was carried out, from September 2017 to August 2020, in the general surgery service of Hermanos Ameijeiras Hospital. The sample consisted of 270 patients who underwent major elective surgery of the colon, liver, bile duct or pancreas and were applied the program to improve postoperative recovery. Results: In 79.6 percent of patients, the nasogastric tube was removed in the operating room after the intervention, a fact associated with faster recovery of intestinal function, shorter stay, as well as fewer complications, readmissions and reinterventions. In 60 percent of the patients, the oral route was started at six hours after surgery, while 79.6 percent of them tolerated a soft diet at 48 hours. These patients presented fewer complications and mortality. Conclusions: In the context of a program to improve postoperative recovery after elective abdominal surgery, nasogastric tube removal on the intervention day, with early opening of the oral route and rapid progression to a soft diet, are well-tolerated actions that have a positive effect on postoperative evolution(AU)

Parachute mitral valve.

An asymptomatic 30-year-old male was referred for a transthoracic echocardiogram because of a systolic murmur that was noted on a pre-employment physical exam. Transthoracic imaging demonstrated a single papillary muscle from which the chordae of both mitral valve leaflets were attached. The mitral valve was seen to have a parachute-like configuration. Given the benign nature of the presentation, the patient did not seek further investigation.

Incidentally found guidewire during bacterial endocarditis workup.

A 67-year-old female with recent hospitalization for pneumonia was transferred to our facility for high fevers and positive blood cultures for staph aureus. During her treatment for pneumonia, central venous catheter was placed. A systolic murmur was found in conjunction with fever and notable premature ventricular contractions on telemetry monitoring. Chest x-ray and transesophageal echocardiography were then performed, and a free guidewire was identified which was later successfully removed under interventional radiology.

Biventricular apical thrombi in a patient presenting with new-onset dilated cardiomyopathy.

The diagnosis of an apical left ventricular thrombus in the setting of a dilated cardiomyopathy is not uncommon. However, biventricular apical thrombi in this setting is unusual. We present a case of a 67-year-old man who was admitted with new onset heart failure with biventricular apical thrombus formation in the absence of a hypercoagulable state.

Resultados de una encuesta multicentros sobre recuperación posoperatoria y razones para cambiar prácticas / Results of a multicenter survey on postoperative recovery and reasons for changing practices

Introducción: Los Programas de Recuperación Posoperatoria Mejorada (Enhanced Revovery After Surgery, ERAS, por sus siglas en inglés), también denominados de "rehabilitación multimodal quirúrgica" o "Fast-track" constituyen estrategias perioperatorias para mejorar la recuperación postoperatoria de forma segura. Objetivo: Evaluar el conocimiento y la aplicación práctica de evidencias científicas actuales que sostienen a los programas de Recuperación Posoperatoria Mejorada. Métodos: Se realizó una investigación cualitativa en 5 servicios de cirugía general de hospitales universitarios de la capital. Se aplicó un cuestionario anónimo a 107 médicos especialistas y residentes de 3er. y 4to. año de la especialidad. Resultados: El 40 por ciento de los encuestados no tenía conocimiento de la existencia de los programas de rehabilitación multimodal. Las evidencias relacionadas con la descompresión naso-gástrica, el ayuno preoperatorio y la preparación mecánica del colon, fueron las menos conocidas, con porcientos de respuestas no acordes a evidencias actuales de 62,2 por ciento, 50,1 por ciento y 50,1 por ciento, respectivamente. Conclusiones: Importantes evidencias científicas actuales en varias acciones claves de la recuperación postoperatoria no son bien conocidas y por ende no han sido incorporadas a la práctica médica(AU)

Introduction: Enhanced recovery after surgery (ERAS) programs, also known as "surgical multimodal rehabilitation" or "fast-track," are perioperative strategies to improve postoperative recovery safely. Objective: To assess the knowledge and practical application of current scientific evidence that supports enhanced postoperative recovery programs. Methods: A qualitative investigation was carried out in five general surgery services of university hospitals in the capital of Cuba. An anonymous questionnaire was applied to 107 specialist physicians, as well as residents from the third and fourth academic years. Results: 40% of the respondents did not have any knowledge about the existence of multimodal rehabilitation programs. The evidences related to nasogastric decompression, preoperative fasting and mechanical preparation of the colon were the least known, with percentages of responses not in accordance with current evidence, being of 62.2 percent, 50.1 percent and 50.1 percent, respectively. Conclusions: Important current scientific evidences concerning several key actions of postoperative recovery are not well known and, therefore, have not been incorporated into medical practice(AU)

Left ventricular pacemaker wire through patent foramen ovale.

A 53-year-old male status post pacemaker placement three months prior for sinus bradycardia presented with worsening dyspnea, holosystolic murmur, and a ventricular-paced right bundle branch block on electrocardiogram. Transesophageal echocardiography demonstrated a pacer wire in the right atrium coursing into the left atrium and ventricle through an undiagnosed patent foramen ovale. The patient underwent surgical repair and repositioning of the pacemaker lead without complication. Although rare, it should be suspected after recent lead placement.

Right ventricular outflow tract obstruction due to a leiomyosarcoma.

A 65-year-old female presenting with worsening dyspnea and notable weight loss were found to have a systolic murmur on physical examination. On workup with computed tomography (CT) angiogram, a solid mass was found extending from the inferior vena cava into the right ventricle. Transesophageal echocardiography demonstrated this mass extension causing right ventricular outflow tract obstruction. After surgical removal, the pathology of the mass was endometrial leiomyosarcoma.

Superior Vena Cava Stent Migration Into the Right Atrium.

Possible stent migration was suspected in this case and confirmed on transesophageal echocardiography. The patient underwent successful stent removal with snaring, as well as subsequent placement of another stent in the superior vena cava without further complications.

Uncorrected Univentricular Heart in an Adult.

An 18-year-old male with an unknown medical history presented with palpitations and paroxysmal episodes of shortness of breath over a 7-year period. Transthoracic echocardiography displayed a univentricle with an ejection fraction of 45%. The patient refused treatment and was lost to follow-up.

Transthyretin Cardiac Amyloidosis as Diagnosed by 99mTc-PYP Scanning in Patients with Acute Heart Failure and Preserved Ejection Fraction.

Transthyretin amyloid deposition is present in 17% of autopsies of patients with heart failure and a preserved ejection fraction (HFpEF). Technetium-pyrophosphate scintigraphy (Tc-PYP) is sensitive and specific to diagnose cardiac transthyretin amyloid deposition (ATTR). The prevalence of ATTR by Tc-PYP was evaluated along with echocardiographic parameters in patients with HFpEF. One-hundred consecutive patients with HFpEF, who had Tc-PYP, were retrospectively evaluated. Echocardiographic variables were analyzed to compare patients with positive versus negative ATTR infiltration. Myocardial ATTR was present in 19% of patients. Individuals with ATTR were older with a mean age of 82 ± 7 versus 75 ± 13 years (P = 0.03), had increased left ventricular hypertrophy with the interventricular septum measuring 1.6 (IQR, 1.4-2.0) versus 1.4 (IQR, 1.3-1.6) cm (P = 0.002), had a greater mean left ventricular mass index of 160 ± 50 g/m versus 131 ± 44 g/m (P = 0.01), and a reduced global longitudinal strain measuring -11% (IQR, -9 to -12) versus -12% (IQR, -10 to -16), P = 0.04. The prevalence of ATTR myocardial deposition demonstrated by Tc-PYP in patients with HFpEF is comparable to that of autopsy studies. It is more common in older patients, with increased left ventricular hypertrophy and reduced global longitudinal strain.

The Effect of Titanium Dioxide Surface Modification on the Dispersion, Morphology, and Mechanical Properties of Recycled PP/PET/TiO2 PBNANOs.

Titanium dioxide (TiO2) nanoparticles have recently appeared in PET waste because of the introduction of opaque PET bottles. We prepare polymer blend nanocomposites (PBNANOs) by adding hydrophilic (hphi), hydrophobic (hpho), and hydrophobically modified (hphoM) titanium dioxide (TiO2) nanoparticles to 80rPP/20rPET recycled blends. Contact angle measurements show that the degree of hydrophilicity of TiO2 decreases in the order hphi > hpho > hphoM. A reduction of rPET droplet size occurs with the addition of TiO2 nanoparticles. The hydrophilic/hydrophobic balance controls the nanoparticles location. Transmission electron microscopy (TEM_ shows that hphi TiO2 preferentially locates inside the PET droplets and hpho at both the interface and PP matrix. HphoM also locates within the PP matrix and at the interface, but large loadings (12%) can completely cover the surfaces of the droplets forming a physical barrier that avoids coalescence, leading to the formation of smaller droplets. A good correlation is found between the crystallization rate of PET (determined by DSC) and nanoparticles location, where hphi TiO2 induces the highest PET crystallization rate. PET lamellar morphology (revealed by TEM) is also dependent on particle location. The mechanical behavior improves in the elastic regime with TiO2 addition, but the plastic deformation of the material is limited and strongly depends on the type of TiO2 employed.

Melt-processing of cellulose nanofibril/polylactide bionanocomposites via a sustainable polyethylene glycol-based carrier system.

Considering the appealing need for an industrially viable approach, this works aims at demonstrating the rapid and easy melt processing of Polylactide (PLA) bio-composites reinforced with cellulose nanofibrils (CNF). For this purpose and against to their high propensity to self-aggregate on processing, an aqueous CNF-based suspension in the presence of polyethylene glycol (PEG) followed by a gentle drying way were performed to provide melt-processable CNF-based masterbatches. Morphological observations coupled with rheological analyses confirmed how the strategy of the PEG-based masterbatch approach facilitated the formation of a well-dispersed and strongly interacting CNF network within the polymeric matrix. At temperatures above Tg, thermo-mechanical characterization showed that the load-bearing capacity of the web-like CNF network was even more apparent and counteracted the PEG plasticizing effect. Thermogravimetric analysis evidenced that in the case of selective positioning at the PLA-PEG interface, CNF mitigated the negative impact of PEG addition on the PLA thermal stability. These results revealed the successfulness of our sustainable organic solvent-free approach to prepare melt-processable CNF masterbatches, which can be readily converted into conventional industrially scalable melt-processing techniques.

The effects of cardiac resynchronization therapy on left ventricular and mitral valve geometry and secondary mitral regurgitation in patients with left bundle branch block.

BACKGROUND: Secondary mitral regurgitation (MR) is common in patients with left bundle branch block (LBBB) undergoing cardiac resynchronization therapy (CRT). We aimed to define CRT effects on left ventricular (LV) and mitral valve (MV) geometry, and their correlation with MR severity. METHODS: Forty-one patients with LBBB and ≥mild secondary MR underwent CRT between 2009 and 2012, and had baseline and follow-up echocardiograms available. Repeated measure and linear regression analyses were performed to assess for changes in MV and LV geometry and MR severity, and associations with follow-up MR grade. RESULTS: The mean age and baseline QRS duration were 65.5 ± 14.9 years and 160 ± 24 ms. At a mean follow-up of 2.6 ± 1.8 years, there was an increase in LV ejection fraction and reductions in LV end-systolic volume index, MR grade, and end-systolic interpapillary muscle distance (P < .05 for all). Linear correlations were observed between follow-up MR grade and baseline MV tenting height (r = .44), left atrial volume index (r = .41), LV end-systolic volume index (r = .4), MV tenting area (r = .38), LV ejection fraction (r = -.34), and end-systolic interpapillary muscle distance (r = .34) (P < .05 for all). Multiple regression analysis revealed associations between follow-up MR grade and baseline MV tenting height (ß/mm = 0.42, P = .006) and left atrial volume index (ß/mL/m2  = 0.4, P = .008), independent of QRS duration (ß/ms=-0.07; P = 0.6) and nonischemic cardiomyopathy (ß = -0.34, P = .02). CONCLUSIONS: Cardiac resynchronization therapy in patients with LBBB and secondary MR results in LV and MV geometric reverse remodeling and decreases MR severity. Extent of baseline MV tethering is independently associated with persistent MR at follow-up.