Classification Predictive Model for Air Leak Detection in Endoworm Enteroscopy System.

Current enteroscopy techniques present complications that are intended to be improved with the development of a new semi-automatic device called Endoworm. It consists of two different types of inflatable cavities. For its correct operation, it is essential to detect in real time if the inflatable cavities are malfunctioning (presence of air leakage). Two classification predictive models were obtained, one for each cavity typology, which must discern between the "Right" or "Leak" states. The cavity pressure signals were digitally processed, from which a set of features were extracted and selected. The predictive models were obtained from the features, and a prior classification of the signals between the two possible states was used as input to different supervised machine learning algorithms. The accuracy obtained from the classification predictive model for cavities of the balloon-type was 99.62%, while that of the bellows-type was 100%, representing an encouraging result. Once the models are validated with data generated in animal model tests and subsequently in exploratory clinical tests, their incorporation in the software device will ensure patient safety during small bowel exploration.

Endoworm: A new semi-autonomous enteroscopy device.

Using enteroscopes with therapeutic capacity to explore the small intestine entails certain limitations, including long exploration times, patient discomfort, the need for sedation, a high percentage of incomplete explorations and a long learning curve. This article describes the advances and setbacks encountered in designing the new Endoworm enteroscopy system, a semi-autonomous device consisting of a control unit and three cavities that inflate and deflate in such a way that the bowel retracts over the endoscope. The system can be adapted to any commercial enteroscope. Endoworm was tested in different intestine models: a polymethyl methacrylate rigid tube, an in vitro polyester urethane model, an ex vivo pig model and an in vivo animal model. The general behavior of the prototype was evaluated by experienced medical personnel. The mean distance covered through the lumen was measured in each cycle. The system was found to have excellent performance in the rigid tube and in the in vitro model. The ex vivo tests showed that the behavior depended largely on the mechanical properties of the lumen, while the in vivo experiments suggest that the device will require further modifications to improve its performance.

Clinical characteristics, process of care and outcomes among Mexican, Hispanic and non-Hispanic white patients presenting with non-ST elevation acute coronary syndromes: data from RENASICA and CRUSADE registries.

INTRODUCTION: Data regarding management characteristics of non-ST elevation acute coronary syndromes (NSTE ACS) in Mexican, Hispanic and Non- Hispanic white patients are scarce. METHODS: We sought to describe the clinical characteristics, process of care, and outcomes of Mexicans, Hispanics and non-Hispanic whites presenting with NSTE ACS at Mexican and US hospitals. We compared baseline characteristics, resource use, clinical practice guidelines (CPGs) compliance and in-hospital mortality among 3 453 Mexicans, 3 936 Hispanics and 90, 280 non-Hispanic whites with NSTE ACS from the RENASICA and CRUSADE registries. RESULTS: Mexicans were younger with a different cardiovascular risk profile, fewer incidences of hypertension (p<0.001), hyperlipidemia (p<0.001), renal failure (p<0.001) and prior revascularization (p<0.001) but were more likely to be smoking compared with Hispanics and non-Hispanic white populations. Mexicans and Hispanics had a higher incidence of diabetes (p<0.001). At clinical presentation Mexican patients were more likely to have ST depression (p<0.001) but less likely to have left ventricular dysfunction (p<0.001) and troponin stratification (p<0.001). Regarding CPGs compliance, aspirin was used in 90% of patients in all groups, but clopidogrel or unfractionated or low-molecular weight heparin in 50% of patients or less. Mexican patients were less likely to receive glycoprotein IIb/IIIa inhibitors and revascularization. In spite of clinical differences and therapeutic trends, cardiovascular mortality was similar among all groups (Mexicans 4%, Hispanics 4% and non-Hispanic white 5%). In all groups of patients, a poor CPGs compliance was observed. CONCLUSIONS: In a post-hoc analysis, Mexican patients with NSTE ACS had a different cardiovascular risk factor profile and clinical presentation, and less intensive in - hospital treatment than Hispanic and non-Hispanic white patients. However, these differences do not appear to affect in - hospital mortality.

Clinical characteristics, process of care and outcomes among Mexican, Hispanic and non-Hispanic white patients presenting with non-ST elevation acute coronary syndromes: Data from RENASICA and CRUSADE registries / Características clínicas, tratamiento hospitalario y evolución entre población mexicana, latina y anglosajones no hispánicos con infarto agudo del miocardio sin elevación del segmento ST. Datos tomados de los registros RENASICA y CRUSADE

Introduction: Data regarding management characteristics of non-ST elevation acute coronary syndromes (NSTE ACS) in Mexican, Hispanic and Non- Hispanic white patients are scarce. Methods: We sought to describe the clinical characteristics, process of care, and outcomes of Mexicans, Hispanics and non-Hispanic whites presenting with NSTE ACS at Mexican and US hospitals. We compared baseline characteristics, resource use, clinical practice guidelines (CPGs) compliance and in-hospital mortality among 3 453 Mexicans, 3 936 Hispanics and 90, 280 non-Hispanic whites with NSTE ACS from the RENASICA and CRUSADE registries. Results: Mexicans were younger with a different cardiovascular risk profile, fewer incidences of hypertension (p<0.001), hiperlipidemia (p<0.001), renal failure (p<0.001) and prior revascularization (p<0.001) but were more likely to be smoking compared with Hispanics and non-Hispanic white populations. Mexicans and Hispanics had a higher incidence of diabetes (p<0.001). At clinical presentation Mexican patients were more likely to have ST depression (p<0.001) but less likely to have left ventricular dysfunction (p<0.001) and troponin stratification (p<0.001). Regarding CPGs compliance, aspirin was used in 90% of patients in all groups, but clopidogrel or unfractionated or low-molecular weight heparin in 50% of patients or less. Mexican patients were less likely to receive glycoprotein IIb/IIIa inhibitors and revascularization. In spite of clinical differences and therapeutic trends, cardiovascular mortality was similar among all groups (Mexicans 4%, Hispanics 4% and non-Hispanic white 5%). In all groups of patients, a poor CPGs compliance was observed. Conclusions: In a post-hoc analysis, Mexican patients with NSTE ACS had a different cardiovascular risk factor profile and clinical presentation, and less intensive in - hospital treatment than Hispanic and non-Hispanic white patients. However, these differences do not appear to affect in - hospital mortality.

Introducción: Existe poca información que compara características clínicas y tendencias terapéuticas en población mexicana, hispánica y anglosajona, con síndrome coronario agudo sin elevación del ST (SCA SEST). Métodos: Describimos características clínicas, proceso de atención y evolución hospitalaria en población mexicana, hispánica y anglosajona con SCA SEST, en hospitales mexicanos y americanos. En tres mil cuatrocientos veinticuatro mexicanos, 3 936 hispánicos y 90 280 anglosajones de los registros RENASICA y CRUSADE, se analizaron características basales, uso de recursos, apego a las guías clínicas y mortalidad hospitalaria. Resultados: Los pacientes mexicanos fueron más jóvenes y con diferente perfil de riesgo cardiovascular, por menor incidencia de hipertensión (p< 0.001), hiperlipidemia (p<0.001), insufciencia renal (p<0.001) e historia de revascularización (p< 0.001), pero tuvieron mayor historia de tabaquismo (p<0.001) en comparación con hispánicos y anglosajones. La mayor incidencia de diabetes se observó en pacientes hispánicos y mexicanos (p<0.001). En éstos, al ingreso se observó mayor incidencia de desnivel negativo del ST (p<0.001), y menor grado de disfunción ventricular (p<0.001) y uso de troponinas (p<0.001). En relación al apego de las guías clínicas, en prácticamente todos se utilizó aspirina (90%), pero el uso de clopidogrel y heparina no fraccionada o de bajo peso molecular, sólo se utilizó en aproximadamente el 50%. Los pacientes mexicanos recibieron menos inhibidores de la glicoproteínas IIb / IIIa y menos revascularización. A pesar de algunas diferencias clínicas y terapéuticas, la mortalidad cardiovascular fue similar en los tres grupos (mexicanos 4%, hispánicos 4% y anglosajones 5%). En todos los grupos, el apego a las guías clínicas no fue el ideal. Conclusiones: En un análisis retrospectivo, pacientes mexicanos con un SCA SEST tuvieron diferente perfil de riesgo cardiovascular, presentación clínica y tratamiento hospitalario, que los pacientes hispánicos y anglosajones. Sin embargo, estas diferencias no parecen afectar la mortalidad hospitalaria.

Safety and efficacy of sitaxsentan 50 and 100 mg in patients with pulmonary arterial hypertension.

OBJECTIVE: To assess safety and efficacy of sitaxsentan 50 and 100 mg in patients with pulmonary arterial hypertension (PAH). BACKGROUND: Sitaxsentan is a highly selective endothelin-A receptor antagonist that was recently withdrawn by the manufacturer because of a pattern of idiosyncratic liver injury. METHODS: Before sitaxsentan withdrawal, this 18-week double-blind, placebo-controlled study randomized patients with PAH to receive placebo or sitaxsentan 50 or 100 mg once daily. The primary efficacy endpoint was change from baseline in 6-min walk distance (6MWD) at week 18. Changes in World Health Organization (WHO) functional class and time to clinical worsening (TTCW) were secondary endpoints. The primary efficacy analysis was powered for sitaxsentan 100 mg versus placebo. RESULTS: Of 98 randomized patients, 61% were WHO functional class II at baseline. Improvement from baseline to week 18 in 6MWD occurred with sitaxsentan 100 but not 50 mg; a strong placebo effect was observed. At week 18, WHO functional class was improved or maintained in more patients receiving sitaxsentan 100 mg than placebo (P = 0.038); 0% versus 12% of patients deteriorated, respectively. TTCW was not significantly different for 100-mg sitaxsentan patients than placebo (P = 0.090). Adverse events (AEs) occurring more frequently with sitaxsentan (50 or 100 mg) included headache, peripheral edema, dizziness, nausea, extremity pain, and fatigue; most AEs were of mild or moderate severity. CONCLUSION: Sitaxsentan 100 mg improved functional class but not 6MWD in PAH patients who were mostly WHO functional class II at baseline. No patient receiving sitaxsentan 100 mg experienced clinical worsening; sitaxsentan was well tolerated.

[Alteplase in acute coronary syndromes]. / Registro de Alteplasa en Síndromes Coronarios Agudos con elevación del ST (REALSICA).

OBJECTIVE: The registry intends to establish the safety and security of one-hour 100 mg alteplase infusion and 50 mg in 30 minutes to facilitate percutaneous coronary intervention (PCI) in a cardiology hospital with primary angioplasty program (24 hours 365 days a year) with current doses of unfractionated heparin and enoxaparin. METHODS AND RESULTS: REALSICA II is a prospective registry that included 103 patients with final diagnosis of ST elevation myocardial infarction in which Alpert's quality criteria were used. Seventy two patients were under one-hour 100 mg alteplase infusion and thirty one under 30 minutes 50 mg alteplase infusion to facilitate PCI. Patients were young and predominantly males. In both groups > 50% had extensive ST elevation myocardial infarction and 68% were Killip & Kimball I. The majority received reperfusion > 3 hours after the onset of symptoms. In-hospital and follow-up treatment were compliant with Mexican Cardiology Society guidelines. ECG reperfusion was observed in 59% and TIMI III flow in 19% of PCI group. Any intracranial hemorrhage was observed. Global cardiovascular mortality was 11%. Patients under PCI had low incidence of recurrent ischemia and reinfarction. CONCLUSION: REALSICA registry showed in non-complicate acute myocardial infarction ST elevation safety and security of one-hour 100 mg alteplase infusion with current recommended unfractionated heparin and enoxaparin doses in ST elevation myocardial infarction. In complicated patients the regimen to facilitate PCI was associated with increased hemorrhagic complications and requires further research.

Registro de Alteplasa en Síndromes Coronarios Agudos con elevación del ST (REALSICA) / Alteplase in acute coronary syndromes

OBJECTIVE: The registry intends to establish the safety and security of one-hour 100 mg alteplase infusion and 50 mg in 30 minutes to facilitate percutaneous coronary intervention (PCI) in a cardiology hospital with primary angioplasty program (24 hours 365 days a year) with current doses of unfractionated heparin and enoxaparin. METHODS AND RESULTS: REALSICA II is a prospective registry that included 103 patients with final diagnosis of ST elevation myocardial infarction in which Alpert's quality criteria were used. Seventy two patients were under one-hour 100 mg alteplase infusion and thirty one under 30 minutes 50 mg alteplase infusion to facilitate PCI. Patients were young and predominantly males. In both groups > 50% had extensive ST elevation myocardial infarction and 68% were Killip & Kimball I. The majority received reperfusion > 3 hours after the onset of symptoms. In-hospital and follow-up treatment were compliant with Mexican Cardiology Society guidelines. ECG reperfusion was observed in 59% and TIMI III flow in 19% of PCI group. Any intracranial hemorrhage was observed. Global cardiovascular mortality was 11%. Patients under PCI had low incidence of recurrent ischemia and reinfarction. CONCLUSION: REALSICA registry showed in non-complicate acute myocardial infarction ST elevation safety and security of one-hour 100 mg alteplase infusion with current recommended unfractionated heparin and enoxaparin doses in ST elevation myocardial infarction. In complicated patients the regimen to facilitate PCI was associated with increased hemorrhagic complications and requires further research.

[Risk marker stratification in coronary acute syndromes]. / Marcadores en la estratificación de los síndromes coronarios agudos.

Acute coronary syndromes have a heterogeneous clinical presentation with a broad spectrum for mortality and adverse events. It is mandatory to identify high risk groups for percutaneous coronary intervention and intensive antithrombotic treatment or common risk for standard treatment. In contemporaneous medicine it is important to get adequate risk stratification because the impact of hospitalary costs, antithrombotic and reperfusion treatment on health systems. The current pathophysiology of atherosclerosis is moving from a disease secondary to cholesterol deposit, to an inflammatory disease. In the stratification process, familiar history, chest pain, ST dynamic abnormalities, left ventricular wall motion abnormalities, all have predictive value. The association of indirect endothelial dysfunction, micro or macronecrosis and ventricular dysfunction markers increase this value. In our experience a close relationship among abnormal fibrinolysis, inflammation and anticoagulation proteins with adverse events has been proved in acute coronary syndromes. Other interesting finding--for it accessibility--in acute myocardial infarction under coronary percutaneous intervention is persistent ST elevation, leukocytes and fibrinogen predictive value. In population allelic polymorphisms -455A and -148T and fibrinogen ( >450 mg/dL) were associated with coronary disease. These polymorphisms improve risk stratification of coronary disease to establish a better secondary prevention and treatment.

Marcadores en la estratificación de los síndromes coronarios agudos / Risk marker stratification in coronary acute syndromes

Acute coronary syndromes have a heterogeneous clinical presentation with a broad spectrum for mortality and adverse events. It is mandatory to identify high risk groups for percutaneous coronary intervention and intensive antithrombotic treatment or common risk for standard treatment. In contemporaneous medicine it is important to get adequate risk stratification because the impact of hospitalary costs, antithrombotic and reperfusion treatment on health systems. The current pathophysiology of atherosclerosis is moving from a disease secondary to cholesterol deposit, to an inflammatory disease. In the stratification process, familiar history, chest pain, ST dynamic abnormalities, left ventricular wall motion abnormalities, all have predictive value. The association of indirect endothelial dysfunction, micro or macronecrosis and ventricular dysfunction markers increase this value. In our experience a close relationship among abnormal fibrinolysis, inflammation and anticoagulation proteins with adverse events has been proved in acute coronary syndromes. Other interesting finding--for it accessibility--in acute myocardial infarction under coronary percutaneous intervention is persistent ST elevation, leukocytes and fibrinogen predictive value. In population allelic polymorphisms -455A and -148T and fibrinogen ( >450 mg/dL) were associated with coronary disease. These polymorphisms improve risk stratification of coronary disease to establish a better secondary prevention and treatment.

[Risk profile and survival in patients with heart failure caused by systolic function. Prospective study with 4-year follow-up]. / Perfil de riesgo y supervivencia en pacientes con insuficiencia cardíaca por disfunción sistólica. Estudio prospectivo con seguimiento a cuatro años.

BACKGROUND: Our current knowledge on the prognosis of systolic left ventricular dysfunction has been obtained through multicentric trials performed at third level health care institutions, which usually include patients based on strict inclusion criteria. OBJECTIVE: To establish in systolic left ventricular dysfunction patients, evaluated at a community hospital, a risk profile for adverse cardiovascular events and to know their survival. METHODS: Prospective study with 4 years follow-up. INCLUSION CRITERIA: a) Symptomatic patients with systolic left ventricular dysfunction, b) any NYHA functional class or etiology, c) ejection fraction < 40%. EXCLUSION CRITERIA: a) Asymptomatic patients, b) acute coronary syndrome in the last 6 weeks, c) ventricular dysfunction secondary to pulmonary arterial hypertension, d) severe systemic illness or neoplasms causing disability < 6 months. STATISTICS: Student's test, Chi-square, Yates and Mantel-Haenszel. Unvariant and multivariant logistic regression analysis. Cox and Kaplan-Meier method. Significance was set at p < 0.05. RESULTS: From January 1997 to January 2001, 110 patients were studied, 61% men and 39% women, their age were 61 +/- 13.1 years. Ischemic etiology in 46% and 54%, 68% in III/IV NYHA class and 32% in I/II NYHA class. Basal left ventricular ejection fraction was 28 +/- 6.9%. Patients were followed for 30.11 +/- 18.7 months, with 26% of global mortality. Through lineal, logistic and multivariate regression analysis, the high clinical risk profile was identified, corresponding > 65 years, female gender, hypertension, diabetes mellitus II, ischemic heart disease, III/IV NYHA class and ventricular tachycardia (p = 0.00001). CONCLUSION: In the "real world" of systolic left ventricular dysfunction, the identified risk profile allows stratify high priority subgroup of patients to be enrolled in a cardiac transplant program.

Perfil de riesgo y supervivencia en pacientes con insuficiencia cardíaca por disfunción sistólica: Estudio prospectivo con seguimiento a cuatro años / Prognosis of systolic left ventricular dysfunction

Antecedentes: Conocemos el pronóstico de la insuficiencia cardíaca por disfunción sistólica a través de estudios multicéntricos realizados en centros de tercer nivel que generalmente incluyen pacientes con estrictos criterios de inclusión. Objetivo: Establecer un perfil de riesgo para eventos cardiovasculares adversos y conocer la supervivencia en enfermos de un hospital comunitario con insuficiencia cardíaca por disfunción sistólica. Métodos: Estudio prospectivo con seguimiento a 4 años. Inclusión: a) manifestaciones clínicas de insuficiencia cardíaca por disfunción sistólica, b) cualquier clase funcional de la New York Heart Association (NYHA), c) disfunción sistólica de cualquier etiología, d) FE del ventrículo izquierdo < 40%. Exclusión: a) paciente asintomático, b) síndrome coronario agudo en las últimas 6 semanas, c) disfunción ventricular secundaria hipertensión arterial pulmonar, d) enfermedad sistémica grave o neoplasia que límite la vida < 6 meses. Estadística: t de Student, chi cuadrada, Yates y Mantel-Haenszel. Análisis de regresión logística univariado y multivariado. Curvas de supervivencia de Cox y Kaplan-Meier. Significancia estadística: p < de 0.05. Resultados: de enero de 1997 a enero del 2001, 110 pacientes fueron incluidos, 61% del sexo masculino y 39% femeninos, con edad de 61 ± 13.1 años. Se consideró etiología isquémica en 46% y no isquémica en 54%, al ingreso la clase funcional fue III/IV en el 68% y I/II en el 32% con una FE de 28 ± 6.9%. La media de seguimiento fue de 30.11 ± 18.71 meses y se observó una mortalidad global del 26%. A través de los modelos de regresión lineal, logística y multivariado se identificó como perfil de alto riesgo para eventos adversos cardiovasculares: edad > 65 años, sexo femenino, hipertensión arterial sistémica, diabetes mellitus, cardiopatía isquémica, clase III-IV de la NYHA y taquicardia ventricular. (p = 0.00001). Conclusión: En el "mundo real" de la insuficiencia cardíaca por disfunción sistólica, el perfil de riesgo identificado por una mayor morbilidad y mortalidad, permite estratificar un subgrupo de pacientes con prioridad alta para integrarse a un programa de trasplante cardíaco.

Background: Our current knowledge on the prognosis of systolic left ventricular dysfunction has been obtained through multicentric trials performed at third level health care institutions, which usually include patients based on strict inclusion criteria. Objective: To establish in systolic left ventricular dysfunction patients, evaluated at a community hospital, a risk profile for adverse cardiovascular events and to know their survival. Methods: Prospective study with 4 years follow-up. Inclusion criteria: a) Symptomatic patients with systolic left ventricular dysfunction, b) any NYHA functional class or etiology, c) ejection fraction < 40%. Exclusion criteria: a) Asymptomatic patients, b) acute coronary syndrome in the last 6 weeks, c) ventricular dysfunction secondary to pulmonary arterial hypertension, d) severe systemic illness or neoplasms causing disability < 6 months. Statistics: Student's t test, Chi-square, Yates and Mantel-Haenszel. Unvariant and multivariant logistic regression analysis. Cox and Kaplan-Meier method. Significance was set at p < 0.05. Results: From January 1997 to January 2001, 110 patients were studied, 61% men and 39% women, their age were 61 ± 13.1 years. Ischemic etiology in 46% and 54%, 68% in III/IV NYHA class and 32% in I/II NYHA class. Basal left ventricular ejection fraction was 28 ± 6.9%. Patients were followed for 30.11 ± 18.7 months, with 26% of global mortality. Through lineal, logistic and multivariate regression analysis, the high clinical risk profile was identified, corresponding > 65 years, female gender, hypertension, diabetes mellitus II, ischemic heart disease, III/IV NYHA class and ventricular tachycardia (p = 0.00001). Conclusion: In the "real world" of systolic left ventricular dysfunction, the identified risk profile allows stratify high priority subgroup of patients to be enrolled in a cardiac transplant program. (Arch Cardiol Mex 2003; 73:197-204).