Comparison of standard balloon and drug-coated balloon angioplasty in patients with the below-the-knee peripheral artery disease

SUMMARY OBJECTIVE: The objective of this study was to compare the interventions of percutaneous transluminal drug-coated balloon angioplasty (DCB PTA) and standard PTA in the treatment of patients with the below-the-knee peripheral artery disease (BTK PAD). METHODS: Overall, 196 patients (113 males and 83 females; mean age: 63.56±11.94 years; 45-83 years) were treated with PTA for BTK PAD between June 2014 and March 2019. RESULT: Standard PTA (group 1; 96 patients) and DCB PTA (group 2; 100 patients) results were analyzed and compared retrospectively. No statistically significant difference was found between the mean ages of group 1 and 2 patients (p=0.371, p>0.05). Demographic and clinical data were compared and no any statistically significant differences was found between the two groups. Comparing in terms of the iliac lesion, there was no statistically significant difference between the two groups. However, a statistically significant difference was found between the two groups in terms of frequency of popliteal lesions (p=0.001; p<0.05). There was not a statistically significant difference between the two groups in terms of other lesions. In addition, limb salvage rates were 82.0% (18 amputations) and 65.6% (33 amputations) in the drug-release balloon group and the naked balloon group, at the end of 1 year, respectively. No distal embolism, limb-threatening ischemia, and mortality were observed in any patients. CONCLUSIONS: Based on this study, patients in the DCB group had significantly higher rates of primary patency as compared with the other patients.

Prevalencia de enfermedad arterial oclusiva crónica de extremidades inferiores en pacientes de alto riesgo cardiovascular pertenecientes a un centro de atención primaria mediante el uso del índice tobillo-brazo / Prevalence of peripheral arterial disease of lower extremities in high cardiovascular risk patients from primary care using the ankle-brachial index

Resumen Objetivo: La enfermedad arterial oclusiva crónica de extremidades inferiores (EAOC EEII) ha sido subestimada y subdiagnosticada especialmente a nivel de atención primaria. El objetivo de este estudio fue estimar la prevalencia de EAOC EEII en pacientes de alto riesgo cardiovascular pertenecientes a un centro de salud familiar. Materiales y Método: Estudio observacional de corte transversal. Se calculó un tamaño muestral de 246 pacientes, con una potencia estadística del 80% y un nivel de confianza del 95%, seleccionándolos aleatoriamente de 1.361 pacientes con riesgo cardiovascular alto del CESFAM Cordillera Andina, a quienes se les realizó la medición del índice tobillobrazo (ITB). Se estimaron IC 95% para cada media y porcentaje reportado, considerándose un valor de p significativo menor de 0,05 en las pruebas estadísticas utilizadas. Resultados: Se observó un ITB < 0,9 en el 43,2% (114), donde el 33,7% (89) refería síntomas de claudicación intermitente, mientras que un 9,5% (25) se encontraba asintomático. El mayor porcentaje de pacientes con EAOC EEII se observó en el grupo etario entre 60 y 80 años, que en conjunto alcanzaba el 85,1% de los pacientes con esta patología, siendo significativamente menor en pacientes menores de 60 y mayores de 80 años (p < 0,001). Conclusión: Encontramos una prevalencia de enfermedad arterial oclusiva crónica de extremidades inferiores de un 43,2% en pacientes de riesgo cardiovascular alto, quienes no presentaban este diagnóstico previamente. El índice tobillobrazo corresponde a un examen simple, rápido y con una gran utilidad diagnóstica por lo que debería considerarse su incorporación en las guías ministeriales para la evaluación de pacientes cardiovasculares en atención primaria.

Aim: The peripheral arterial disease (PAD) has been underestimated and underdiagnosed particularly at primary care setting. Our aim was to calculate the prevalence of PAD in high cardiovascular risk patients from a primary care center. Materials and Method: Is an observational, cross section study. We calculated a sample size of 246 patients, with a power of 80% and a significance level of 95%, who were selected randomly from 1.361 high cardiovascular risk patients according to the Framingham score, who attended at Cordillera Andina primary care center, measuring the anklebrachial index (ABI) in this group of patients. A 95% confidence interval was calculated for each mean and proportion and a p value less than 0.05 were considered as significant for all statistic tests. Results: We found an ABI < 0.9 in the 43.2% (114) of the sample, where 33.7% (89) presented symptoms of intermittent claudication, while 9.5% (25) did not have symptoms. The highest proportion of PAD was detected in patients between 60 and 80 years, who represented 85.1% of the patients with PAD, being significantly less its prevalence in people under 60 and over 80 years (p < 0.001). Conclusion: A prevalence of PAD of 43.2% in high cardiovascular risk patients who did not have this diagnosis before was found. The anklebrachial index is an easy, fast and very useful test to diagnose PAD in the majority of patients at primary care level, as consequent, its incorporation to clinical guidelines should be evaluated.

Repercussão da doença arterial periférica na tolerância ao exercício e na qualidade de vida de idosos e o papel da fisioterapia cardiovascular: artigo de revisão / The impact of peripheral arterial disease on exercise tolerance and quality of life in the elderly and the role of cardiovascular physiotherapy: review article

Resumo A doença arterial periférica tem como principal sintoma a claudicação intermitente, fator que resulta em incapacidade funcional, comprometendo a qualidade de vida. Esta revisão objetivou fazer um levantamento sobre os impactos ocasionado pela doença nos idosos, investigando as possíveis contribuições da fisioterapia cardiovascular. Para isso, realizou-se uma busca nas bases de dados MEDLINE, LILACS, SciELO, Scopus, Science Direct e PEDro, a qual identificou 7.587 estudos. Desses, sete atenderam aos critérios de elegibilidade, sendo então agrupados e analisados conforme o nível de evidência, grau de recomendação e qualidade metodológica. Pôde-se observar um considerável impacto da doença sobre a tolerância ao exercício e a qualidade de vida. Quanto à abordagem terapêutica desses desfechos, os estudos relataram que houve melhora na deambulação e na qualidade de vida, aumento da capacidade funcional e redução da dor. No que se refere à modalidade de tratamento, a maioria das pesquisas incluíram exercícios aeróbicos.

Abstract The primary symptom of peripheral arterial its intermittent claudication; a condition that causes functional disabilities, compromising quality of life. This review aimed to survey the impacts of this disease on the elderly, investigating possible contributions that cardiovascular physiotherapy has to offer. Searches were run on the MEDLINE, LILACS, SciELO, Scopus, Science Direct, and PEDro databases, identifying 7,587 studies. Seven of these met the eligibility criteria and were grouped and analyzed according evidence level, recommendation grade, and methodological quality. It was observed that this disease is responsible for considerable impact on exercise tolerance and quality of life. Regarding the therapeutic approach to these outcomes, the studies reported that there were improvements in walking and quality of life, increased functional capacity, and reduced pain. With regard to the treatment modality, most research included aerobic exercises.

Importância do destreinamento físico sobre a capacidade funcional em indivíduos com doença arterial obstrutiva crônica periférica: estudo transversal piloto / Importance of physical detraining in functional capacity of individuals with chronic peripheral arterial occlusive disease: a cross-sectional pilot study

Resumo Contexto O treinamento físico é uma estratégia bem estabelecida para a reabilitação da capacidade funcional de indivíduos com doença arterial obstrutiva crônica periférica (DAOP). No entanto, após um programa de treinamento físico, alguns indivíduos podem descontinuá-lo, causando destreinamento. A literatura é escassa sobre os efeitos do destreinamento físico em indivíduos com DAOP; portanto, torna-se importante investigar os efeitos nessa temática. Objetivos Avaliar os efeitos do destreinamento físico sobre a capacidade funcional em indivíduos com DAOP. Métodos Estudo transversal com 22 indivíduos. Os participantes foram divididos em dois grupos: grupo destreinamento (GD), grupo controle (GC). Foram avaliadas a distância percorrida no teste de caminhada de 6 minutos (DTC6M) e a distância livre de dor claudicante (DLDC), a qual é referida pela distância percorrida até o início da claudicação, ou seja, sem dor. Resultados A média da idade foi de 66±8 para o GD e de 67±7 para o GC. Tanto a DTC6M como a DLDC não apresentaram diferenças entre os grupos (p = 0,428 e p = 0,537, respectivamente). Conclusões O presente estudo piloto permite concluir que indivíduos com DAOP que participaram de um programa de treinamento físico e posterior destreinamento não tiveram efeitos superiores na sua capacidade funcional em relação a indivíduos que não participaram de programa de treinamento físico. O resultado do presente estudo serve para incentivar a manutenção da prática de exercício físico, visto que o treinamento físico deixa de ser efetivo se ocorrer destreinamento.

Abstract Background Physical training is a well-established strategy for rehabilitation of the functional capacity of individuals with chronic peripheral arterial occlusive disease (PAOD). However, some individuals quit training after participating in a physical training program, undergoing detraining. There is scant literature on the effects of physical detraining in individuals with PAOD and it is therefore important to investigate the effects of this phenomenon. Objectives The objective of this article was to evaluate the effects of physical detraining on functional capacity in individuals with PAOD. Methods Cross-sectional study with 22 individuals. Participants were divided into two groups: a detraining group (DG) and a control group (CG). The distance covered in the 6-minute walk test (6MWTD) and the pain-free walking distance (PFWD) were evaluated. The PFWD is the distance covered until claudication begins, i.e., the distance covered without pain. Results Mean age was 66 ± 8 in the DG and 67 ± 7 in the CG. There were no differences between the groups in either the 6MWTD or the PFWD (p = 0.428; p = 0.537, respectively). Conclusions The present pilot study allows us to conclude that the functional capacity of individuals with PAOD who participated in a physical training program and subsequently underwent detraining was not superior in relation to individuals who did not participate in a physical training program. The results of the present study serve to encourage maintenance of physical exercise, since physical training is no longer effective if detraining occurs.

Terapia gênica de isquemia de membro é uma realidade? / Is gene therapy for limb ischemia a reality?

Resumo O conceito de terapia angiogênica surgiu no início da década de 90, o que pode ser feito com genes que codificam fatores de crescimento para promover a formação de novos vasos e o remodelamento de vasos colaterais. Como o procedimento dessa terapia geralmente consiste em apenas injeções locais de vetores, esse processo é pouco invasivo, rápido e de simples realização. Entretanto, desde as primeiras evidências clínicas do efeito de terapia gênica com o fator de crescimento de endotélio vascular (vascular endothelial growth factor, VEGF) vistos nos pacientes com doença arterial obstrutiva periférica até hoje, apenas dois fármacos de terapia angiogênica foram aprovados, um na Rússia e outro no Japão, o que parece um número muito pequeno diante do grande número de investimentos feitos por meio de estudos pré-clínicos e clínicos. Afinal, podemos considerar que a terapia angiogênica já é uma realidade?

Abstract The concept of angiogenic therapy emerged in the early 1990s. The method employs genes that encode growth factors to promote formation of new vessels and remodeling of collateral vessels. Since the procedure involved in this therapy usually only consists of local injections of vectors, the process is minimally invasive, quick, and simple to perform. However, since the first clinical evidence of the effects of gene therapy with vascular endothelial growth factor (VEGF) was observed in patients with peripheral artery disease, to date only two angiogenic therapy drugs have been approved, one in Russia and another in Japan, which seem a very small number, in view of the large volume of investment made in pre-clinical and clinical studies. After all, can we conclude that angiogenic therapy is a reality?

Experiencia de la angioplastía en miembros inferiores en la enfermedad arterial periférica en una clínica privada en el sur de Colombia / Experience of angioplasty in lower limbs in peripheral arterial disease in a private clinic in southern Colombia

OBJETIVO: Evaluar las características de los pacientes sometidos a angioplastía en miembros inferiores, así como establecer posibles asociaciones entre los factores que lleven a complicaciones de la misma. MATERIALES Y MÉTODO: Estudio descriptivo, observacional, retrospectivo de corte transversal durante 18 meses en el que se evaluaron aquellos pacientes con enfermedad arterial periférica sometidos a angioplastía de miembros inferiores, sus características demográficas, clínicas, quirúrgicas y las complicaciones postoperatorias. RESULTADOS: Se evaluaron 158 registros de pacientes con edades entre 30 y 95 años. El 65,2% (n = 103) de los procedimientos se realizaron de forma electiva, los vasos intervenidos con mayor frecuencia fueron la arteria femoral superficial (64%), el tipo de intervención endovascular más frecuente fue la combinación de balón + balón medicado (32,9%), el tratamiento farmacológico postoperatorio más usado fue la combinación de ácido acetilsalicílico (ASA) y clopidogrel (86,1%). Se presentaron 21 casos de complicaciones, la más frecuente fue la amputación menor (52%). Se encontró mayor riesgo de amputación menor cuando el procedimiento quirúrgico es realizado de forma urgente (p = 0,012; OR [IC 95%]: 4,8 [1,4-16,5]). DISCUSIÓN: La complicación posangioplastía con diferencia estadísticamente significativa fue la amputación menor cuando el procedimiento se realizó de manera urgente, esta asociación pudo estar relacionada con el estado clínico del paciente en el momento del ingreso y no con el procedimiento quirúrgico. CONCLUSIÓN: La angioplastía realizada de urgencias fue un procedimiento tan seguro como cuando se realiza de forma programada, dado por la misma proporción de sangrado o disección arterial.

AIM: Evaluate the characteristics of patients undergoing angioplasty in the lower limbs, as well as to establish possible associations between the factors leading to complications. MATERIALS AND METHODS: Observational descriptive, cross-sectional and retrospective study conducted during 18 months in which patients with peripheral arterial disease undergoing angioplasty of the lower limb were included, as well their demographic, clinical, and surgical characteristics and the postoperative complications. RESULTS: 158 records of patients between 30 and 95 years were evaluated. 65.2% (n = 103) of the procedures were performed not urgently, the most frequently intervened vessels were the superficial femoral artery (64%), the most frequent type of endovascular intervention was the combination of balloon + medicated ball (32.9%), the most used postoperative pharmacological treatment was the combination of acetylsalicylic acid (ASA) and clopidogrel (86.1%). There were 21 cases of complications, the most frequent complication was minor amputation (52%). A higher risk of minor amputation was found when the surgical procedure was performed urgently (p = 0.012, OR [95% CI]: 4.8 [1.4-16.5]). DISCUSION: The post-angioplasty complication with statistically significant difference was minor amputation when the procedure was performed urgently, this association was related to the clinical status of the patient at the time of admission and not to the surgical procedure. CONCLUSION: Angioplasty performed urgently is as safe as elective procedures, given by the same proportion of bleeding or arterial dissection.

Arteriopatía periférica asociada a marihuana / Marijuana-associated peripheral arteriopathy

La arteriopatía por marihuana debe ser considerada en pacientes jóvenes con arteriopatía periférica sin factores de riesgo para ateroesclerosis. Se ha descrito por primera vez en 1960 y existen más de 100 casos en la literatura. Si bien se tiende a considerar como una entidad independiente de la tromboangeítis obliterante o enfermedad de Leo Buerger, debido a los hallazgos la consideramos dentro del espectro de esta última. Presentamos dos casos de pacientes jóvenes con enfermedad vascular periférica asociada al consumo de marihuana, luego de excluir otras enfermedades. El tratamiento es el cese del consumo. Es indispensable valorar el uso de drogas en pacientes jóvenes que se presentan con arteriopatía periférica.

The marijuana arteriopathy should be considered in young patients with peripheral arterial disease with no risk factors for atherosclerosis. It was described for the first time in 1960 and since then there have been about 100 cases published in the literature. Although it tends to be considered as an independent entity of thromboangiitis obliterans or Leo Buerger´s disease, in the light of the last findings it is possible to consider it within the spectrum of the latter. We present two cases of young patients with peripheral vascular disease associated with marijuana use where other associated illnesses had been excluded and where the mainstay of treatment has been the cessation of marijuana consumption. It is essential to assess drug use in young patients presenting with peripheral arterial disease.

O uso do balão com paclitaxel no tratamento da reestenose intra-stent no segmento fêmoro-poplíteo / Use of paclitaxel-coated balloon to treat in-stent restenosis in femoropopliteal segments

Resumo Contexto A reestenose intra-stent por hiperplasia miointimal pós-angioplastia é uma intercorrência frequente e que limita a perviedade do procedimento a longo prazo. A terapia com balões revestidos de droga com ação antiproliferativa pode ser uma alternativa no tratamento dessa complicação. Objetivos Demonstrar eficácia e as complicações (óbito, grandes amputações, etc.) do balão farmacológico no tratamento da reestenose intra-stent de segmento femoropoplíteo. Métodos Estudo de coorte retrospectivo de 32 pacientes consecutivos tratados entre os anos de 2012 e 2016, submetidos a terapia de reestenose intra-stent de segmento femoropoplíteo com angioplastia com balão farmacológico revestido com paclitaxel. A taxa de sucesso foi mensurada pela ocorrência de sucesso do procedimento e reestenose inferior a 50% em avaliação por eco-Doppler colorido 30, 90 e 180 dias após o procedimento. Resultados Quatro pacientes (12,5%) apresentaram reestenose superior a 50%, sendo um (3,1%) após 90 dias e três (9,4%) após 180 dias, conferindo uma taxa de sucesso de 87,5% ao procedimento. Após 180 dias, todos os pacientes referiam melhora ou cessação dos sinais e/ou sintomas apresentados antes do procedimento. Não houve óbitos, e complicações ocorreram apenas em dois casos, no pós-operatório imediato. Conclusões Os resultados a curto prazo da terapia com balão farmacológico são promissores, com redução na taxa de reestenose e baixo índice de complicações. Ainda precisam ser apresentados estudos demonstrando os efeitos a longo prazo dessa terapia, assim como seu impacto econômico quando comparada a outros procedimentos.

Abstract Background In-stent restenosis due to myointimal hyperplasia after angioplasty is common and limits long-term patency. Treatments using balloons coated with antiproliferative drugs may offer an alternative option for this pathology. Objectives To demonstrate the efficacy and complications (death, major amputations, etc.) of drug-coated balloons for treatment of in-stent restenosis in femoropopliteal segments. Methods This was a retrospective cohort study of 32 consecutive patients treated between 2012 and 2016 who underwent treatment to correct in-stent restenosis in the femoropopliteal segment using paclitaxel-coated balloons. The success rate was measured in terms of technical success and restenosis of less than 50% on Doppler ultrasonography at 30, 90, and 180 days after the procedure. Results Four patients (12.5%) exhibited restenosis greater than 50%, one (3.1%) after 90 days and three (9.4%) after 180 days, equating to a success rate of 87.5% of procedures, and by 180 days all patients experienced improvement or cessation of the signs and/or symptoms they had presented prior to the procedure. There were no deaths and complications occurred in just 2 cases in the immediate postoperative period. Conclusions Short-term results are promising, with reductions in the magnitude of restenosis and a low rate of complications. Further studies are needed that can demonstrate the long-term effects and the economic impacts in comparison to other procedures.

Resultados do uso de stents de nitinol superflexíveis na artéria femoral superficial / Outcomes after implantation of superflexible nitinol stents in the superficial femoral artery

As intervenções endovasculares na artéria femoral superficial para o tratamento da doença arterial oclusiva periférica têm crescido nas últimas décadas. A primeira e a segunda geração de stents na artériafemoral superficial falharam em demonstrar a melhora da perviedade do vaso tratado, devido às altas taxas defratura. O objetivo deste estudo foi avaliar os desfechos clínicos no curto prazo com o uso de stents de nitinolsuperflexíveis de terceira geração no tratamento de lesões ateroscleróticas na artéria femoral superficial. Métodos: Trata-se de um estudo retrospectivo, realizado em único centro, no período de junho de 2013 a maio de 2014. Um total de 27 pacientes foi submetido à angioplastia com stents de nitinol superflexíveis de terceira geração em lesões ateroscleróticas da arterial femoral superficial. Resultados: A média de idades foi de 68 ± 12 anos, 55,6% eram do sexo feminino e 74,1%, diabéticos. Os pacientes foram classificados em TASC B e C em 77,7% dos casos. O sucesso técnico foi de 100%. Houve aumento do índice tornozelo-braquial de 0,35 ± 0,1 pré-intervenção para 0,75 ± 0,2 na alta hospitalar. O seguimento médio dos pacientes foi de 6,7 ± 2,3 meses. A taxa de patência primária foi de 96,3%. A taxa de salvamento de membro foi de 100%. Não ocorreram fraturas de stent documentadas por raios X. Conclusões: A angioplastia com uso de stent de nitinol superflexível de terceira geração demonstrou ser efetiva no tratamento das lesões ateroscleróricas da artéria femoral superficial...

Endovascular interventions in the superficial femoral artery for the treatment of peripheral arterial occlusive disease have increased over the last decades. The first- and second-generation stents in the superficial femoral artery have failed to demonstrate improved patency of the treated vessel due to high fracture rates. The aim of this study was to evaluate the clinical, short-term outcomes of using third-generation superflexible nitinol stents in the treatment of atherosclerotic lesions in the superficial femoral artery. Methods: This was a retrospective study carried out in a single center, from June 2013 to May 2014. A total of 27 patients underwent angioplasty with third-generation superflexible nitinol stents in atherosclerotic lesions of the superficial femoral artery. Results: The mean age was 68 ± 12 years, 55.6% were females, and 74.1% were diabetics. Patients were classified as TASC B and C in 77.7% of cases. Technical success was 100%. There was an increase in the anklebrachial index from 0.35 ± 0.1 before the intervention to 0.75 ± 0.2 at hospital discharge. The mean followupof patients was 6.7 ± 2.3 months. The primary patency rate was 96.3%. The limb salvage rate was 100%. There were no stent fractures documented by X-rays. Conclusions: Angioplasty with third-generation superflexible nitinol stent placement was shown to beeffective in the treatment of atherosclerotic lesions of the superficial femoral artery...

Endovascular treatment of occlusive central venous disease: one center's experience / Tratamento endovascular da doença venosa oclusiva central: experiência de um centro

INTRODUCTION: The majority of cases of stenosis or occlusion of central veins are the result of central catheters, arteriovenous fistulas, neoplasms or traumas and these conditions can cause severe cases of venous hypertension or reduce the flow through fistulas. The objective of this study is to analyze the results of central venous angioplasties conducted at our hospital. METHODOLOGY: We conducted a retrospective and descriptive study to analyze the results of central venous angioplasties conducted from 2010 to 2012 at a university hospital run by the Universidade Estadual de Londrina, Brazil. We calculated primary and secondary success rates and analyzed whether or not stents were used and complications occurred during a 6-month follow-up period. RESULTS: A total of 25 central venous angioplasties were conducted. Twenty-four (96%) of these were because of catheter-related intimal hyperplasia and one was to treat the effects of compression by a tumor. Fifteen (60%) angioplasties were to correct stenosis and ten (40%) were because of occlusions, with a one-hundred percent success rate for all stenosis-related procedures. However, none of the cases of occlusion could be treated endovascularly. Patency during the 6-months follow-up period was 80% after reinterventions. CONCLUSIONS: Despite good results observed after primary interventions for stenoses, it must be accepted that all current treatment options for chronic occlusive venous disease will, sooner or later, lead to restenosis or occlusion. Venous occlusions constitute a challenge demanding the development of new techniques and new materials. Prevention is paramount, through avoidance of central catheterization and early creation of arteriovenous fistulas...

INTRODUÇÃO: A estenose ou a oclusão de veias centrais ocorre, na maioria das vezes, em consequência de catéteres centrais, fístulas arteriovenosas, neoplasias e traumas, podendo levar a quadros severos de hipertensão venosa e de redução do débito dessas fístulas. O presente trabalho tem como objetivo analisar os resultados obtidos nas angioplastias venosas centrais em nosso hospital. METODOLOGIA: Realizamos um estudo retrospectivo, descritivo, analisando os resultados obtidos nas angioplastias venosas centrais realizadas no Hospital Universitário da Universidade Estadual de Londrina durante os anos de 2010 a 2012. Verificamos as taxas de sucesso primário e secundário, a utilização ou não de stents e as complicações, analisadas durante um período de acompanhamento de seis meses. RESULTADOS: Foram realizadas 25 angioplastias venosas centrais, sendo 24 (96%) por hiperplasia intimal relacionada ao uso de catéteres e uma por compressão tumoral. Destas, 15 (60%) eram estenoses e dez (40%) eram oclusões, obtendo-se sucesso primário técnico em todos os procedimentos relacionados à estenose. Contudo, nenhum caso de oclusão pode ser tratado por via endovascular. No acompanhamento de seis meses, após reintervenções, observamos perviedade de 80%. CONCLUSÃO: Apesar dos bons resultados observados nas intervenções primárias sobre as estenoses, indiscutivelmente todas as opções atuais para o tratamento da doença venosa oclusiva crônica irão levar, precoce ou tardiamente, à reestenose ou à oclusão. As oclusões venosas constituem uma incitação para o desenvolvimento de novas técnicas e novos materiais. A prevenção assume papel preponderante, com redução da implantação de catéteres...