Secondary Forms of Hypertension
• Primary aldosteronism (present in 20% of resistant hypertensives)
• Kidney disease
• Renal artery stenosis-fibromuscular-young
• Atherosclerotic-old
• Pheochromocytoma (rare)
• Hypothyroidism
• Hyperthyroidism (systolic hypertension)
• Hyperparathyroidism
• Aortic coarctation (rare: do not forget to perform blood pressure measurement in the leg on the first visit)
Assuming that the hypertension has failed to respond to conventional therapies, consideration should be given to the use of hydralazine or minoxidil (in conjunction with a β-blocker and a diuretic). Because direct vasodilators cause significant reflex activation of sympathetic nervous system and fluid retention, their use should be accompanied by the co-administration of a β-blocker and a loop diuretic.
Aggressive cardiovascular risk management is mandatory in patients with RH due to their increased risk of events.
Another current consideration is referral to a center that performs clinical trials on renal denervation. The DenervHTN trial just reported from Europe shows an additive effect of renal denervation to maximum medical therapy in refractory hypertension patients, (average 5.1 medications) controlled for adherence. In the near future, clinical trials on carotid baroreceptors stimulation, and iliac arteriovenous fistulae may also be restarted.
Referral to a hypertension specialist (or becoming one through the American Society of Hypertension Program) may also be helpful. Shared decision making with the patient regarding outcomes and side effects is critically important.
The problem of RH can be treated successfully in a systematic fashion and on a rational basis.
