A 62-year-old man returns for evaluation of hypertension. For the past year, his blood pressure has become increasingly difficult to control despite the addition of several antihypertensive medications. He also has type 2 diabetes mellitus, intermittent claudication, erectile dysfunction, hyperlipidemia, and coronary artery disease. Currently he takes metoprolol, amlodipine, hydrochlorothiazide, lisinopril, and hydralazine for hypertension. The patient smokes cigars daily and drinks alcohol socially. His blood pressure is 165/95 mm Hg, and pulse is 76/min. On examination, the point of maximal impulse is palpated lateral to the midclavicular line on the left. Heart sounds are normal. A bruit is heard on auscultation to the left of the umbilicus. There is trace pedal edema. The distal pulses of the lower extremities are diminished bilaterally. Laboratory results are as follows: Which of the following is the most appropriate next step in management of this patient?

Question

A 62-year-old man returns for evaluation of hypertension.  For the past year, his blood pressure has become increasingly difficult to control despite the addition of several antihypertensive medications.  He also has type 2 diabetes mellitus, intermittent claudication, erectile dysfunction, hyperlipidemia, and coronary artery disease.  Currently he takes metoprolol, amlodipine, hydrochlorothiazide, lisinopril, and hydralazine for hypertension.  The patient smokes cigars daily and drinks alcohol socially.  His blood pressure is 165/95 mm Hg, and pulse is 76/min.  On examination, the point of maximal impulse is palpated lateral to the midclavicular line on the left.  Heart sounds are normal.  A bruit is heard on auscultation to the left of the umbilicus.  There is trace pedal edema.  The distal pulses of the lower extremities are diminished bilaterally.  Laboratory results are as follows:  Which of the following is the most appropriate next step in management of this patient?

Quizplus · Accepted Answer

Explanation: 11ec2b69_c1c5_836e_8f63_e740f7bcc5d8_MD0005_00 This patient has resistant hypertension, which is defined as persistent hypertension in spite of the concurrent use of 3 or more antihypertensive agents of different classes, including a diuretic at maximal tolerated dose. All patients with resistant hypertension should be evaluated for a secondary cause of hypertension. secondary cause of hypertension Renovascular hypertension is the most common correctable cause of secondary hypertension and should be suspected in patients with clinical clues suggestive of renovascular disease (see Table). Renal artery stenosis (RAS) is present in about 1% of patients with mild hypertension, in up to 45% of Caucasian patients with severe hypertension, and in 25%-35% of patients with peripheral arterial disease (as in this patient with reduced peripheral pulses). Such patients should have noninvasive assessment with renal duplex Doppler ultrasonography or CT or MR angiography (MRA) for the diagnosis of RAS. Renal Doppler ultrasound is the initial preferred modality in patients with renal insufficiency due to risk of contrast-induced nephropathy (with CT angiography) and nephrogenic systemic fibrosis (with gadolinium-enhanced MRA). Noncontrast MRA may be performed when available. (Choice B) A high plasma aldosterone/renin ratio is seen in patients with primary aldosteronism that presents with resistant hypertension or hypertension associated with unexplained hypokalemia. The presence of diffuse atherosclerosis with abdominal bruit makes RAS and renovascular hypertension the likely cause of resistant hypertension in this patient. (Choice C) Renal angiography with iodinated contrast should be avoided in this patient due to the risk of worsening renal function associated with contrast-induced nephropathy. (Choices D and E) This patient is using an ACE inhibitor (lisinopril) as part of his antihypertensive regimen. The additional use of spironolactone or losartan is contraindicated in patients with renal insufficiency due to the risk of worsening renal failure and hyperkalemia. Educational objective: Renovascular hypertension should be suspected in patients with resistant hypertension and signs of diffuse atherosclerosis. Such patients should be evaluated with noninvasive testing with renal duplex Doppler ultrasonography or CT or MR angiography. Due to risk of contrast-induced nephropathy and nephrogenic systemic fibrosis when performing CT and gadolinium MR angiography, respectively, these should be avoided in patients with renal insufficiency. References: Contemporary imaging techniques for the diagnosis of renal artery stenosis. (http://www.ncbi.nlm.nih.gov/pubmed/15983776) Color-coded duplex ultrasound for diagnosis of renal artery stenosis and as follow-up examination after revascularization. (http://www.ncbi.nlm.nih.gov/pubmed/18383154)

A 62-Year-Old Man Returns for Evaluation of Hypertension