ABC | Volume 114, Nº3, March 2020

Statement Brazilian Position Statement on Resistant Hypertension – 2020 Arq Bras Cardiol. 2020; 114(3):576-596 dysfunction and, consequently, participates in the development of metabolic syndrome and CV and renal lesions associated with RHTN. Thus, mineralocorticoid receptor blockade improves endothelial dysfunction and contributes to a better response to RHTN and TOD therapies. 118,119 During the diagnostic evaluation, all patients with RHTN (not only those with hypokalemia) should be evaluated for the occurrence of hyperaldosteronism. 33 Screening should include the assessment of the plasma aldosterone concentration (PAC expressed in ng/dL) to plasma renin activity (PRA expressed in ng/mL/hr) called aldosterone/renin ratio (ARR). This method has excellent sensitivity but may yield false-positive results. Therefore, adoption of the minimum PAC and PRA values of 15 ng/dL and 0.5 ng/mL/h, respectively, are recommended. An ARR ≥ 100 establishes the diagnosis of hyperaldosteronism, while values < 20 to 30 indicate a low probability of the disease, and values in between detect “individuals potentially affected” by this condition. 120 In the latter case, tests assessing the renin-aldosterone axis (saline infusion test, walking, use of diuretics) may be performed. Tomography or magnetic resonance imaging is used for imaging identification of adrenal adenomas or hyperplasia. The absence of a visible tumor on tomography does not exclude the presence of a microadenoma, hence the importance of searching for excessive aldosterone production. Functional images, obtained by adrenal scintigraphy, may be useful in detecting adenomas and may differentiate them from nodular hyperplasia in up to 90% of the cases. Adrenal vein blood sampling can be used to confirm lateralization in aldosterone secretion and the presence of unilateral adenoma. 120,121 In terms of treatment, unilateral resection usually corrects excessive aldosterone production and potassium loss in unilateral adenomas. The BP response to surgical treatment varies. Cases of hyperplasia benefit from aldosterone receptor blockade. 121 7.3.2. Pheochromocytoma Pheochromocytoma is a rare neuroendocrine tumor that originates from chromaffin cells (cells producing catecholamines). The most common clinical manifestation of this condition is elevated BP, and the disease may arise from the adrenal medulla or extra-adrenal paraganglia (paragangliomas). Clinical exacerbation peaks between the third and fourth decades of life, but 10% of the cases arise in childhood. These tumors may be sporadic or associated with genetic syndromes. 122,123 They are usually unilateral; however, in familial syndromes, they may be bilateral, multiple, or extra- adrenal, and benign or malignant (5 to 26% of the cases). This etiology should be investigated in all patients presenting with RHTN and/or symptoms or signs suggestive of hyperadrenergic spells. Paroxysmal hypertension occurs in 30% of the cases, triggered by regular physical activity, exercises with increased intensity, surgical procedures, and use of certain substances such as tricyclic antidepressants, histamine, and opioids. Paroxysms may be accompanied by headache (60 to 90%), sweating (55 to 75%), and palpitations (50 to 70%). Symptoms of heart failure and electrocardiographic abnormalities may indicate myocarditis induced by catecholamine excess. At diagnosis, measurement of metanephrines (catecholamine metabolites) in plasma and 24-hour urine has higher sensitivity and specificity than direct catecholamine measurement. When laboratory tests are not elucidative, clonidine suppression test may be performed (administration of clonidine 0.2 mg and measurement of catecholamines 1 hour before and 2 hours after the medication). For a topographic diagnosis of the tumors and, eventually, the metastases, the recommended imaging methods are computed tomography and magnetic resonance imaging, both of which have sensitivity close to 100% for adrenal tumors. Whole-body 131 or 123 metaiodobenzylguanidine (MIBG) has sensitivity of 56 to 85% (malignant tumors) and high specificity. Octreoscan, bone mapping, and PET scan (with different markers) can be decisive when previous localization tests are negative or in the investigation of malignant disease. Treatment is surgical. However, in preoperative or chronic medication therapy, alpha-blockers (prazosin, doxazosin, and dibenzyline) are initially used, combined or not with other agents such as beta-blockers (after effective alpha blockade), ACEIs, and CCBs. Control of BP levels and volume replacement are recommended before the surgical intervention. 124 Sodium nitroprusside can be used in acute crises and during surgery. 124 7.3.3. Hypothyroidism and Hyperthyroidism Hypertension may affect 40% of the patients with thyroid disorders, while correction of the glandular dysfunction usually results in BP control. 125 If BP levels remain high after correction of the hypothyroidism or hyperthyroidism, use of antihypertensive drugs is indicated. 32,126 Causes of SecH in patients with RHTN are summarized in Table 1. 8. Non-Pharmacological Treatment Coordinator: Sérgio Emanuel Kaiser. Authors: Gil Fernando Salles, Maria de Fátima de Azevedo, and Lucélia Batista Neves Cunha Magalhães. 8.1. Weight Loss Several mechanisms contribute to maintain high BP in obese patients with hypertension, including OSA, sympathetic hyperactivity, endothelial dysfunction, and modification of the intestinal microbiota – all these factors can promote an inflammatory phenotype and perpetuate a vicious cycle. 130 Patients with BMI ≥ 30 kg/m 2 are 50% more likely to have uncontrolled BP than those with normal BMI (< 25 kg/m 2 ). 131 A BMI > 40 kg/m 2 triples the chances of the requirement of multiple drugs for BP control. 132 A weight loss of 10 kg is associated with mean reductions of 6.0 mmHg in systolic BP and 4.0 mmHg in diastolic BP. 133 Surprisingly, there is no consistent evidence on the effect of diet-induced weight loss in patients with RHTN, but this recommendation meets the common sense and the evidence available in other subgroups. There are also no data on the effect of bariatric surgery on BP in this subgroup. A recent randomized trial showed a reduction of at least 30% in the 587