The prognosis of resistant hypertension (by the previ- compared with the prognosis of those who more readily achieve control, has not been fully ascertained; however, risk of MI, stroke, ESRD, and death in adults with resistant hypertension and CHD may be 2- to 6-fold higher than in hypertensive adults without resistant hypertension.S11.1-4 S11.1-6 The evaluation of resistant hypertension involves consideration of many patient characteristics, pseudoresistance (BP technique, white coat hypertension, and medication compliance), and screen- ing for secondary causes of hypertension (Figure 10; Section 5.4; Table 13). The term refractory hypertension has been used to refer to an extreme phenotype of antihypertensive treatment fail- ure, defined as failure to control BP despite use of at least 5 anti- hypertensive agents of different classes, including a long-acting thiazide-type diuretic, such as chlorthalidone, and a mineralocor- ticoid receptor antagonist, such as spironolactone.S11.1-7 The prevalence of refractory hypertension is low; patients with refractory hypertension experience high rates of CVD compli- cations, including LVH, HF, and stroke. Treatment of resistant hypertension involves improv- ing medication adherence, improving detection and correc- tion of secondary hypertension, and addressing other patient Pharmacological therapy with com- binations of medications with complementary mechanisms of action provides an empirical approach that enhances BP control while mitigating untoward effects of potent vasodilators (eg, fluid retention and reflex tachycardia). CCBs, inhibitors of RAS, and chlorthalidone comprise a common 3-drug regimen.S11.1-11 Considerable evidence indicates that the addition of spironolac- tone to multidrug regimens provides substantial BP reductionS11.1-12 when compared with placebo. 