Renal hypoperfusion from renal artery stenosis (RAS) activates the renin-angiotensin system, which in turn causes volume overload and hypertension. Atherosclerosis and fibromuscular dysplasia are the most common causes of renal artery stenosis. Recurrent flash pulmonary edema, also known as Pickering syndrome, is commonly associated with bilateral renal artery stenosis. There should be a high index of clinical suspicion for renal artery stenosis in the setting of recurrent flash pulmonary edema and severe hypertension in patients with atherosclerotic disease. Duplex ultrasonography is commonly recommended as the best initial test for the detection of renal artery stenosis. Computed tomography (CT) angiography (CTA) or magnetic resonance (MR) angiography (MRA) are useful diagnostic imaging studies for the detection of renal artery stenosis in patients where duplex ultrasonography is difficult. If duplex ultrasound, CTA, and MRA are indeterminate or pose a risk of significant renal impairment, renal angiography is useful for a definitive diagnosis of RAS. The focus of medical management for RAS relies on controlling renovascular hypertension and aggressive lifestyle modification with control of atherosclerotic disease risk factors. The restoration of renal artery patency by revascularization in the setting of RAS due to atherosclerosis may help in the management of hypertension and minimize renal dysfunction.

published_or_final_version / Medicine / Doctoral / Doctor of Philosophy

<p>Renal artery stenosis (RAS) is a potentially curable cause of hypertension and azotemia. Besides intra-arterial renal angiography there are several non-invasive techniques utilized to diagnose patients with suspicion of renal artery stenosis. Removing the stenosis by revascularization to restore unobstructed blood flow to the kidney is known to improve and even cure hypertension/azotemia, but is associated with a significant complication rate. </p><p>To visualize renal arteries with x-ray techniques a contrast medium must be used. In a randomized, prospective study the complications of two types of contrast media (CO₂ and ioxaglate) were compared. CO₂ was not associated with acute nephropathy, but induced nausea and had lower attenuation differences compared to Ioxaglate. Acute nephropathy was related to the ioxaglate dose and the risk was evident even at very low doses if the patients were azotemic with creatinine clearance <40 ml/min. </p><p>Evaluating patients for clinically relevant renal artery stenosis can be done utilizing several non-invasive techniques. MRA was retrospectively evaluated and shown to be accurate in detecting hemodynamically significant RAS. In a prospective study of 58 patients, evaluated with four methods for renal artery stenosis, it was shown that MRA and CTA were significantly better than ultrasonography and captopril renography in detecting hemodynamically significant RAS. The standard of reference was trans-stenotic pressure gradient measurement, defining a stenosis as significant at a gradient of ≥15 mmHg. The discrepancies were mainly found in the presence of borderline stenosis.</p><p>The outcome of percutaneous revascularization procedures showed a technical success rate of 95%, clinical benefit in 63% of treated patients, 30-day mortality 1.5% and major complication rate of 13%. The major complication rate for patients with baseline serum creatinine >300µmol/l was 32%. Our results compare favorably with published studies and guidelines.</p>

Renal artery stenosis (RAS) is a potentially curable cause of hypertension and azotemia. Besides intra-arterial renal angiography there are several non-invasive techniques utilized to diagnose patients with suspicion of renal artery stenosis. Removing the stenosis by revascularization to restore unobstructed blood flow to the kidney is known to improve and even cure hypertension/azotemia, but is associated with a significant complication rate. To visualize renal arteries with x-ray techniques a contrast medium must be used. In a randomized, prospective study the complications of two types of contrast media (CO2 and ioxaglate) were compared. CO2 was not associated with acute nephropathy, but induced nausea and had lower attenuation differences compared to Ioxaglate. Acute nephropathy was related to the ioxaglate dose and the risk was evident even at very low doses if the patients were azotemic with creatinine clearance &lt;40 ml/min. Evaluating patients for clinically relevant renal artery stenosis can be done utilizing several non-invasive techniques. MRA was retrospectively evaluated and shown to be accurate in detecting hemodynamically significant RAS. In a prospective study of 58 patients, evaluated with four methods for renal artery stenosis, it was shown that MRA and CTA were significantly better than ultrasonography and captopril renography in detecting hemodynamically significant RAS. The standard of reference was trans-stenotic pressure gradient measurement, defining a stenosis as significant at a gradient of ≥15 mmHg. The discrepancies were mainly found in the presence of borderline stenosis. The outcome of percutaneous revascularization procedures showed a technical success rate of 95%, clinical benefit in 63% of treated patients, 30-day mortality 1.5% and major complication rate of 13%. The major complication rate for patients with baseline serum creatinine &gt;300µmol/l was 32%. Our results compare favorably with published studies and guidelines.

A nefropatia isquêmica é caracterizada pela piora da função renal e perda de massa renal decorrente de uma estenose hemodinamicamente significativa. A reversibilidade potencial da injúria renal após intervenção terapêutica é ponto crucial. A intervenção terapêutica tem como objetivo restabelecer um fluxo renal adequado e conseqüentemente melhorar a taxa de filtração glomerular e obter um melhor controle pressórico. Objetivo: avaliar e comparar os marcadores prognósticos tradicionais e novos (quantificação da ecogenicidade renal - relação parênquimo-sinusal (RPS) e histologia renal) na nefropatia isquêmica em pacientes submetidos à angioplastia com ou sem implante de stent. Material e Métodos: foi realizado um estudo prospectivo de casos consecutivos no HC-FMUSP com duração de dois anos e sete meses. A população foi composta de 20 pacientes com diagnóstico de estenose de artéria renal e com creatinina sérica acima 1,5mg/dl, submetida à angioplastia renal com ou sem implante de stent. Coleta de Dados e Procedimentos: realizados antes da intervenção - exames laboratoriais (creatinina sérica e cálculo da depuração de creatinina estimada - Cockcroft-Gault e da depuração de creatinina do rim submetido à angioplastia, proteinúria de 24 horas, hemoglobina, ácido úrico sérico, dosagem de atividade de renina plasmática (ATP) em veias renais e veia cava inferior); exames de imagem e de radioisótopos (ultra-sonografia renal com histograma, Doppler renal, renograma com captopril e arteriografia renal digital); biópsia renal com realização de processamento para microscopia óptica. Após a intervenção os pacientes foram divididos em: grupo 1- melhora da função renal (n=14) e grupo 2 - piora ou estabilização da função renal (n=6). End-points: Depuração de creatinina estimada - Cockcroft- Gault no primeiro mês após à angioplastia. Análise Estatística: os dados foram o submetidos a análise uni variada, com aplicação do teste t de Student ou do teste de Mann-Whitney. O teste exato de Fisher foi utilizado para comparação de proporções. A curva ROC foi realizada para análise do RPS. Resultados: A dosagem de creatinina sérica (p=0,04), a depuração da creatinina no rim submetido à angioplastia (p=0,02), o tamanho renal (p=0,02), o renograma com captopril - teste positivo (0,04) e o RPS (p=0,02) apresentaram diferença significativa entre os grupos. Através da análise da curva ROC para o RPS, o cálculo da área sob a curva ROC foi 0,833 (0.63- 1.0, IC95%). Conclusão: O RPS é um novo teste capaz de prever a evolução da taxa de filtração glomerular após angioplastia com e sem stent na nefropatia isquêmica / The ischemic nephropathy is characterized by the worsening of the renal function and loss of renal mass due to an renal artery stenosis hemodynamically significant. To the potential reversibility of the renal injury after therapeutic intervention is a crucial point and the therapeutic intervention has as objective to reestablish an appropriate renal flow, and consequently improve the glomerular filtration rate and obtain a better pressorical control. Objective: to evaluate and to compare the markers traditional and new prognostics (measure of the renal ecogenicity - relationship sinusal parênquimum (RSP) and renal histology) in the ischemic nephropathy in patients submitted to the therapeutic intervention with success. Material and Methodology: prospective studies of consecutive cases were accomplished in HC-FMUSP in two years and seven months time. The population was composed of 20 patients with diagnosis of renal artery stenosis with plasma creatinine level above 1.5 mg/dl; that had indication of therapeutic intervention - angioplasty with or without stenting. Collection of Data and Procedures: accomplished before the intervention - laboratorial exams (plasma creatinine level and calculation of creatinine clearance by Cockcroft-Gault formula, calculation of creatinine clearance of kidney submitted to the therapeutic intervention, proteinuria of 24 hours, haemoglobin, serum uric acid and renin in renal veins and inferior cava vein), image exams and of radioisotopes (renal ultrasonography with histogram, renal Doppler ultrasonography, captopril-enhanced 99mTc-DTPA renal scintigraphy and digital renal arteriography) and renal biopsy with processing accomplishment for optical microscopy. After the intervention the patients were separate in group 1 - it gets better of the renal function (n=14) and group 2 - it worsens or stabilization of the renal function (n=6). End-points: Creatinine clearance by Cockcroft-Gault formula the first month after therapeutic intervention with success. Statistical analysis: the data were submitted the unvarieted analysis, with application of the Student test or the Mann-Whitney test. Also the exact test of Fisher was used for proportions comparison. ROC curv was used for RPS analisys Results: Plasma creatinine level (p=0,04), creatinine clearance of kidney submitted to the therapeutic intervention (p=0,02), renal size (p=0,02), renal scintigraphy with positive captopril-test (p=0,04) and RSP (p=0,02) presented significant difference among the groups. In the ROC curve analysis of RSP, the calculated area under the curve was 0.833 (95% CI, 0.63-1.0). Conclusion: the RSP is a new test to predict the evolution of glomerular filtration rate after angioplasty with or without stenting

EINLEITUNG: Die CT- Angiographie (CTA) ist eine neue Methode zum anatomischen Nachweis pathologischer Veränderungen am Gefäßsystem. Die Wertigkeit der an unserem Institut durchgeführten CT- Angiographien bezüglich der Diagnostik von Nierenarterienstenosen sollte untersucht werden. Außerdem sollten die einzelne Rekonstruktionsarten auf ihren Nutzen geprüft werden. MATERIAL UND METHODEN: Die Nierenarterien von 23 Patienten wurden sowohl angiograpisch als auch mit CTA untersucht. Aus dem Datensatz jeder Untersuchung wurden Axiale Schnittbilder (AS), axiale und coronale multiplanare Reformationen (cMPRa, cMPRc), 3D- Oberflächenrekonstruktion (SSD) und Maximum- Intensitäts- Projektion (MIP) angefertigt. Ohne Kenntnis des Angiographie- Befundes wurden in der ersten Befundungssitzung alle CTA- Rekonstruktionen einzeln beurteilt. Dabei kam eine fünfteilige Stenosengraduierung zum Einsatz. In der zweiten Befundungssitzung wurde die Diagnose anhand aller CTA- Rekonstruktionen eines Falles gestellt. Sensitivität, Spezifität und Kappa ergaben sich aus dem Vergleich mit den Angiographie- Befunden. ERGEBNISSE: Die CTA konnte relevante Nierenarterienstenosen (Lumeneinengung >50%) mit einer Sensitivität von 92,9 % und einer Spezifität von 86,7 % nachweisen. Der CTA- Stenosegrad stimmte bei Anwendung einer Unterteilung in fünf Kategorien in 65,9 % der Fälle mit dem der Angiographie überein (kappa = 0,468). Bei der Beurteilung der einzelnen Rekonstruktion lieferten die AS (Sensitivität 78,6 %, Spezifität 90,0 %, kappa 0,692) und die MIP (Sensitivität 71,4 %, Spezifität 96,7 %, kappa 0,726) die besten Resultate. Die cMPRa und cMPRc besaßen durch die ausschließliche Filmbefundung eine deutlich niedrigere diagnostische Qualität. Tendenziell wurde der Stenosegad mittels CTA unterschätzt. SCHLUSSFOLGERUNG: Die CTA besitzt eine hohe Wertigkeit bei der Diagnostik von Nierenarterienstenosen. Unsere Ergebnisse decken sich mit denen anderer Studien. Der Einsatz der CTA bei Verdacht auf eine Nierenarterienstenose kann die Zahl unnötiger Angiographien deutlich reduzieren. Zur Befunderhebung sollten die AS und die MIP regelmäßig genutzt werden. / PURPOSE: To evaluate the accuracy of Computed Tomographic Angiography (CTA) in the detection of renal artery stenosis in our department and to investigate the role of the different reformattings in making the right diagnosis. MATERIALS AND METHODS: CTA and conventional Arteriography were performed on 23 Patients and axial slices (AS), curved axial multiplanar reformatting (cMPRa), curved coronal multiplanar reformatting (cMPRc), shaded surface display (SSD) and maximum intensity projections (MIP) were performed. During the first reading- session all blinded images were reviewed seperately, while all reformattings of one patient were analysed in the second reading session by one experienced radiologist, using a five- point- scale to determine the grade of the stenosis. RESULTS: Stenoses greater than 50% could be depicted by CTA with a sensitivity of 92,9 % and a specifity of 86,7 %. Applying a 5 five- point- scale, 65,9% of the diagnoses met the ones made by angiography (kappa= 0,468). MIP and AS were the most usefull reformattings with sensitivity, specifity and kappa reaching 71,4 %, 96,7 %, 0,726 and 78,6 %, 90 %, 0,692respectively. A tendency for underestimating the degree of the stenoses was notable. CONCLUSIONS: CTA has a high accuracy in diagnosing renal artery stenoses. Our results do not differ much from other studies on this technique. Applying CTA in suspected renal artery stenosis can reduce the amount of unnessecary arteriographies. For best results, MIP and AS should always be reviewed.

A crescente incidência da aterosclerose na população adulta e a obstrução da artéria renal são condições relacionadas à hipertensão renovascular. Independente das comorbidades presentes, a estenose de artéria renal é, por si só, importante causa de mortalidade cardiovascular. Frente a tal realidade, determinar o exame ou exames que possam identificar precocemente esta condição mórbida pode mudar a história natural da doença renovascular. Objetivo: Definir sensibilidade, especificidade, valor preditivo positivo e valor preditivo negativo dos exames não invasivos na estenose da artéria renal. Associar estes achados com a análise vascular quantitativa (QVA) das artérias renais. Métodos: Estudo prospectivo com 61 pacientes recrutados entre janeiro de 2008 e agosto de 2011. As características populacionais, os exames de ultrassom Doppler, cintilografia renal com DTPA e a tomografia computadorizada foram selecionados e seus resultados comparados à arteriografia digital das artérias renais e ao QVA. Resultados: A média das idades foi de 65,43 (DP 8,7) anos. Das variáveis relacionadas à população do estudo e comparadas à arteriografia, duas identificaram relação com a estenose da artéria renal, a disfunção renal e os triglicerídeos. A mediana do ritmo de filtração glomerular de 52,8 ml/min/m2 identificou uma razão de chance para estenose de artéria renal de até 10 vezes. Os triglicerídeos associaram-se a uma menor presença de estenose na artéria renal, p < 0,037. A análise da sensibilidade, especificidade, valor preditivo positivo e negativo dos diferentes testes diagnósticos permitiu identificar aquele que melhor detectava a estenose nos suspeitos e afastava nos sadios. O ultrassom doppler com sensibilidade de 82,90%, especificidade 70,00%, valor preditivo positivo 85,00% e preditivo negativo 66,70% e a angiotomografia com sensibilidade de 68,30%, especificidade 80,00%, valor preditivo positivo 87,50% preditivo negativo de 55,20%, foram os exames que permitiram predizer as maiores chances de estenose da artéria renal nos portadores e afastar na população sem estenose. A associação das características populacionais com o QVA, permitiu identificar duas novas variáveis, o sexo e a idade. A média do grau de estenose, 33,47% (DP 29,55) quantificada pelo QVA, identificou menores graus de estenose que na análise visual dos angiogramas. Exames não invasivos positivos em estenoses menores do que 60% da luz do vaso também foram identificados . Os resultados identificados pela curva ROC demonstraram respectivamente a arteriografia, a angiotomografia e o ultrassom Doppler como os exames com melhores chances em predizer estenose significativa da artéria renal. Conclusão: A angiotomografia e o ultrassom Doppler trouxeram qualidade e alta possibilidade no diagnóstico da estenose da artéria renal, com vantagem para o segundo, pois não há necessidade do uso de meio de contraste na avaliação de uma doença que, frequentemente, está acompanhada por portadores de disfunção renal, disfunção ventricular esquerda grave e diabetes melito. A incorporação de uma forma objetiva de medidas das artérias renais aprimora os resultados da angiografia invasiva. / The increasing incidence of atherosclerosis in adults and renal artery stenosis are conditions related to renovascular hypertension. Regardless all risk factors, renovascular stenosis is by itself an important cause of cardiovascular mortality. Choosing appropriate tests that can early identify this morbid condition can change the natural history of renovascular disease. Objective: To define sensitivity, specificity, positive and negative predictive value of non- invasive tests in renal artery stenosis. Associate these findings with the renal arteries quantitative vascular analysis (QVA). Methods: Prospective study with 61 patients selected between January 2008 and August 2011. The population characteristics, Doppler ultrasound scanning, DTPA renal scintigraphy and computed tomography were selected and their results compared with renal arteries digital angiography as well as the comparison to QVA. Results: The mean age was 65.43 (SD 8.7). The risk factors of the study population compared to angiography identified two variables: renal dysfunction and triglycerides. The median glomerular filtration rate of 52.8 ml/min/m2 identified an odds ratio for renal artery stenosis up to 10 times. Triglycerides were associated with lower presence of renal artery stenosis p < 0.037. The analysis of sensitivity, specificity, positive and negative predictive values of different diagnostic tests allowed the identification of the stenosis in the group of suspected patients and this possibility was discarded in the group of healthy patients. Doppler ultrasound scanning with 82.90% sensitivity, 70.00% specificity, 85.00% positive predictive value, 66.70% negative predictive value and computed tomography with 68.30% sensitivity, 80.00% specificity, 87.50% positive predictive value and 55.20% negative predictive value. These were the tests which supplied better chances to predict renal artery stenosis in patients with or without stenosis. The relationship of population characteristics with QVA identified two new variables, gender and age. The mean degree of stenosis 33.47% (SD 29.55) quantified by QVA identified lesser degrees of stenosis than in visual analysis of angiograms. Non- invasive positive stenoses less than 60% of vessel lumen were identified. The results identified by the ROC curve showed respectively angiography, computed tomography, and Doppler ultrasound scanning as better chances for predicting renal artery stenosis. Conclusion: Computed tomography, Doppler ultrasound scanning have brought high quality and ability in the diagnosis of renal artery stenosis, with an advantage to Doppler, which avoids the use of contrast medium in the evaluation of a disease that is often accompanied by patients with renal dysfunction, severe left ventricular dysfunction and diabetes mellitus. The introduction of new methodology to measure renal arteries will certainly improve the angiography results.

INTRODUÇÃO: Em pacientes hipertensos com suspeita de doença arterial coronária (DAC), indicações para a realização de arteriografia renal no mesmo procedimento da cinecoronariografia estão bem estabelecidas. Entretanto, em hipertensos com suspeita de estenose de artéria renal (EAR) com indicação de arteriografia renal, não estão bem definidos os determinantes da presença de DAC grave. OBJETIVOS: Avaliar a prevalência e os determinantes de DAC grave em pacientes hipertensos com indicação de arteriografia renal por suspeita de EAR. METODOLOGIA: Oitenta e dois pacientes com suspeita clínica de EAR foram submetidos à cinecoronariografia e arteriografia renal no mesmo procedimento. Lesão arterial significativa em artérias renal e/ou coronária foi definida por obstrução luminal maior ou igual a 70%. RESULTADOS: Obstrução luminal significativa, tanto em artéria coronária quanto em renal, foi encontrada em 39% dos pacientes. Os pacientes com DAC grave apresentaram idade mais avançada (63±12 vs. 56±13 anos; p=0,03), maior prevalência de angina (41 vs. 16%; p=0,013), maior diâmetro do átrio esquerdo (44,7 vs. 40,6mm; p=0,005) e maior velocidade de onda de pulso (12,6 vs. 10,7 m/s, p=0,02), comparados com os pacientes sem DAC grave. A presença de EAR significativa esteve associada a uma maior prevalência de DAC grave comparada a pacientes sem a lesão (66% vs. 22%; p<0,001). A análise multivariada demonstrou que EAR70% esteve associada com DAC grave de maneira independente (OR: 11,48; 95%CI 3,2-40,2; p<0,001), mesmo em pacientes sem angina (OR: 13,48; 95%CI 2,6-12,1; p<0,001). CONCLUSÃO: Há elevada prevalência de doença coronária grave em pacientes hipertensos com estenose de artéria renal significativa. A presença de estenose maior ou igual a 70%, verificada em arteriografia renal, é preditor forte e independente para a presença de DAC grave, mesmo na ausência de angina / INTRODUCTION: In patients with suspected coronary artery disease (CAD), indications for performing coronary and renal angiography at the same setting are well established. However, in hypertensive patients with suspected renal artery stenosis (RAS) with indication for renal angiography, it is not well defined the determinants of the presence of severe CAD. OBJECTIVES: We aimed to evaluate the prevalence and determinants of severe CAD in hypertensive patients referred to renal angiography for the diagnosis of RAS. METHODS: Eighty-two consecutive patients with high clinical risk for RAS systematically underwent renal angiography and coronary angiography at the same procedure. Significant RAS and CAD were defined as arterial luminal obstruction 70%. RESULTS: Either significant RAS or significant CAD were present in 32/82 patients (39%). Patients with severe CAD were older (63±12 vs. 56±13 years, p=0.03), had more angina (41 vs. 16%; p=0.013), higher left atrial diameter (44.7 vs. 40,6mm; p=0.005), and higher pulse wave velocity (12.6 vs. 10.7 m/s); p=0.02) compared to patients without significant CAD. Significant RAS was associated with an increased prevalence of severe CAD compared to patients without the lesion (66% vs. 22%, respectively; p<0.001). Binary logistic regression analysis showed that RAS 70% was independently associated with severe CAD (OR: 11.48; 95%CI 3.2-40.2; p<0.001), even in patients without angina (OR: 13.48; 95%CI 2.6-12.1; p<0.001). CONCLUSION: The prevalence of severe CAD in hypertensive patients with significant RAS is high. The presence of RAS 70%, diagnosed by renal angiography, is a strong and useful predictor to identify severe CAD, independently of the presence of angina

INTRODUÇÃO: A hipertensão renovascular (HRV) decorrente da estenose de artéria renal (EAR) é uma patologia potencialmente curável, mas os benefícios da revascularização não são alcançados por todos porque selecionar pacientes com base nos critérios clínicos ou angiográficos pode não ser suficiente para se obter o sucesso clínico. Existe um grande interesse em se desenvolver exames para detectar a presença de EAR e avaliar seu significado funcional. OBJETIVOS: avaliar se a redução da Taxa de Filtração Glomerular (TFG) medida com EDTA-51Cr após o uso de captopril consegue diferenciar pacientes hipertensos com EAR daqueles sem estenose da artéria e avaliar se existe correlação entre as variações da TFG e a evolução de pacientes submetidos a diferentes tratamentos. MÉTODOS: Foram estudados 41 pacientes com hipertensão arterial de difícil controle que foram divididos em dois grupos: GP: 21 pacientes com EAR e GH: 20 pacientes sem EAR. Os pacientes foram submetidos à medida de TFG com EDTA-51Cr pré e após a administração do captopril. Os pacientes do GP realizaram simultaneamente cintilografia com DMSA-99mTc para avaliação da função renal diferencial. Os pacientes com estenose de artéria renal foram subdivididos de acordo com o tratamento recebido: clínico (GP-CL) ou por intervenção (GP-I). As medidas das TFGs antes e após o captopril foram comparadas entre os grupos. Foi também, investigado se a relação pré/pós captopril tinha correlação com a resposta clínica dos pacientes. RESULTADOS: a média da TFG (ml/min./1,73m2) no total de pacientes estudados, foi de 56,7±26,5 na fase pré-captopril e 47,0±24,4 após o captopril. A modificação da TFG determinada pelo captopril,foi avaliada pela relação da filtração glomerular pré/pós-captopril. A média da relação TFG pré/pós-captopril foi 1,36 ±0,54 no grupo total de pacientes e quando foi feita a comparação entre a TFG pré e pós-captopril, houve uma redução significativa (p= 0,016). O GH mostrou relação média da TFG pré/pós-captopril de 1,13, valor significativamente menor que o GP que teve a relação média de 1,57 (p= 0,007). Quando foi avaliada a variação da TFG após o captopril nos dois grupos não foi observada diferença estatisticamente significativa no GH (p=0,68), mas observou-se diferença significativa no GP (p<0,001). No total, 15 pacientes apresentaram melhora dos seus níveis pressóricos, sendo oito do grupo de intervenção e sete do grupo clinico, não havendo diferença estatisticamente significativa em relação à melhora clínica entre os dois grupos (p=0,36). Quando comparamos os pacientes com e sem melhora clínica não se observou diferença significativa na TFG basal (p=0,09) ou na relação TFG pré/pós-captopril (p=0,74). A função renal diferencial obtida pelo DMSA-99mTc pré e pós captopril não mostrou diferença estatisticamente significativa nos rins com e sem estenose, (p=0.09). CONCLUSÃO: O captopril acarreta uma redução significativa da TFG e esta redução é mais acentuada em pacientes com EAR, mas não houve correlação entre as mediadas da TFG e a evolução clínica dos pacientes / INTRODUCTION: Renovascular hypertension (RVH) resulting from renal artery stenosis (RAS) is a potential curable pathology, but the revascularization benefits are not reached among all patients because selecting patients on the basis of clinical and angiographic criteria may not be sufficient to achieve clinical success. There has been increasing interest in developing screening tests capable of accurately detecting the presence of RAS and also of evaluating its functional consequences PURPOSE: the purpose of this study was to evaluate if captopril induced changes in 51Cr-EDTA clearance could be used to differentiate between hypertensive patients with and without renal artery stenosis and to investigate if there was a correlation between these changes and patients clinical response to therapy. METHODS: 41 patients with poor-controlled severe hypertension were studied. Patients were divided into two groups: GP=patients with renal artery stenosis (n=21), and GH=patients without renal artery stenosis (n=20). They were submitted to a Glomerular Filtration Rate (GFR) measurement with EDTA-51Cr pre and post captopril administration. The GP patients were submitted simultaneously to 99mTc-DMSA scintigraphies to estimate individual renal function. GP patients were further subdivided according to the treatment strategy: optimization of clinical treatment (GP-Cl) and interventional procedures (GP-I). The GFRs before and after captopril administration were compared between the groups. It was also investigated if baseline to post-captopril GFR ratio had a correlation to clinical response of patients. RESULTS: The GFR average (ml/min./1,73m2) on the total patients, was 56,7±26,5 on pre-captopril phase and 47,0±24,4 post captopril. The GFR alteration determinated by captopril was evaluated by Baseline/post-captopril GFR ratio. Baseline/post-captopril GFR mean ratio was 1,36 in total patients and the GFR had a significant decrease after captopril administration (p value 0.016). Baseline/post-captopril GFR mean ratio in GH was 1.13, value significantly lower than the GP which had the average relation of 1,57 (p= 0,007). When GFR pre and post-captopril was compared among the two groups separately, there was no significantly difference on the GH (p=0,68), but a expressive difference was observed on GP (p<0,001). 15 patients had a clinical response to the treatment. Clinical response was observed in 8/10 patients from GP-I and 7/11 from GP-Cl and there was not observed a significantly difference between the two groups (p=0,36). Comparing the groups with or without clinical improvement there was not a significantly difference on the GRF baseline (p=0,09) or on or baseline/post-captopril ratio (p=0,74). When evaluating the differential renal function obtained by pre and post-captopril DMSA-99mTc, significantly difference was not observed (p=0.09) for the kidneys with or without stenosis. CONCLUSION: captopril induced a decrease in GFR of hypertensive patients and it is more pronounced in patients with renal artery stenosis, but no correlation was observed between captopril induced decrease in GFR and clinical response of patients submitted to interventional or clinical treatment

INTRODUÇÃO: Em pacientes hipertensos com suspeita de doença arterial coronária (DAC), indicações para a realização de arteriografia renal no mesmo procedimento da cinecoronariografia estão bem estabelecidas. Entretanto, em hipertensos com suspeita de estenose de artéria renal (EAR) com indicação de arteriografia renal, não estão bem definidos os determinantes da presença de DAC grave. OBJETIVOS: Avaliar a prevalência e os determinantes de DAC grave em pacientes hipertensos com indicação de arteriografia renal por suspeita de EAR. METODOLOGIA: Oitenta e dois pacientes com suspeita clínica de EAR foram submetidos à cinecoronariografia e arteriografia renal no mesmo procedimento. Lesão arterial significativa em artérias renal e/ou coronária foi definida por obstrução luminal maior ou igual a 70%. RESULTADOS: Obstrução luminal significativa, tanto em artéria coronária quanto em renal, foi encontrada em 39% dos pacientes. Os pacientes com DAC grave apresentaram idade mais avançada (63±12 vs. 56±13 anos; p=0,03), maior prevalência de angina (41 vs. 16%; p=0,013), maior diâmetro do átrio esquerdo (44,7 vs. 40,6mm; p=0,005) e maior velocidade de onda de pulso (12,6 vs. 10,7 m/s, p=0,02), comparados com os pacientes sem DAC grave. A presença de EAR significativa esteve associada a uma maior prevalência de DAC grave comparada a pacientes sem a lesão (66% vs. 22%; p<0,001). A análise multivariada demonstrou que EAR70% esteve associada com DAC grave de maneira independente (OR: 11,48; 95%CI 3,2-40,2; p<0,001), mesmo em pacientes sem angina (OR: 13,48; 95%CI 2,6-12,1; p<0,001). CONCLUSÃO: Há elevada prevalência de doença coronária grave em pacientes hipertensos com estenose de artéria renal significativa. A presença de estenose maior ou igual a 70%, verificada em arteriografia renal, é preditor forte e independente para a presença de DAC grave, mesmo na ausência de angina / INTRODUCTION: In patients with suspected coronary artery disease (CAD), indications for performing coronary and renal angiography at the same setting are well established. However, in hypertensive patients with suspected renal artery stenosis (RAS) with indication for renal angiography, it is not well defined the determinants of the presence of severe CAD. OBJECTIVES: We aimed to evaluate the prevalence and determinants of severe CAD in hypertensive patients referred to renal angiography for the diagnosis of RAS. METHODS: Eighty-two consecutive patients with high clinical risk for RAS systematically underwent renal angiography and coronary angiography at the same procedure. Significant RAS and CAD were defined as arterial luminal obstruction 70%. RESULTS: Either significant RAS or significant CAD were present in 32/82 patients (39%). Patients with severe CAD were older (63±12 vs. 56±13 years, p=0.03), had more angina (41 vs. 16%; p=0.013), higher left atrial diameter (44.7 vs. 40,6mm; p=0.005), and higher pulse wave velocity (12.6 vs. 10.7 m/s); p=0.02) compared to patients without significant CAD. Significant RAS was associated with an increased prevalence of severe CAD compared to patients without the lesion (66% vs. 22%, respectively; p<0.001). Binary logistic regression analysis showed that RAS 70% was independently associated with severe CAD (OR: 11.48; 95%CI 3.2-40.2; p<0.001), even in patients without angina (OR: 13.48; 95%CI 2.6-12.1; p<0.001). CONCLUSION: The prevalence of severe CAD in hypertensive patients with significant RAS is high. The presence of RAS 70%, diagnosed by renal angiography, is a strong and useful predictor to identify severe CAD, independently of the presence of angina