Infiltration of the sphenopalatine ganglion decreases blood pressure in newly diagnosed and never treated patients with essential hypertension

Background Sphenopalatine ganglion (SPG), an extracranial structure, is connected with the central nervous system (CNS) through sympathetic and parasympathetic nerves. We hypothesized that SPG block through sympathetic nerves anesthesia might decrease blood pressure (BP) in recently diagnosed and never treated middle-aged patients with essential hypertension. Methods We performed SBG block in 22 hypertensive patients (mean age 45 ± 12 years, 15 men). All patients have been subjected to 24 hour ambulatory blood pressure monitoring a week prior the procedure as well as in a period of 21–30 days after the SBG block in order to estimate differences in 24 h average systolic (24 h SBP) and diastolic blood pressure (24 h DBP), daytime, nighttime, pre-awake and early morning SBP and DBP as well as BP load. Results We found that 24 h SBP (p = 0.001) and 24 h DBP (p < 0.001), daytime SBP and DBP (p < 0.001) as well as daytime SBP and DBP load (p = 0.002 and p < 0.001, respectively) were decreased in total population at 21–30 days after SPG block. In 11/22 responders (24 h SBP decrease ≥ 5 mm Hg), SBP and DBP were reduced during overall 24 h and daytime (p < 0.001) and nighttime periods (p = 0.01 and p = 0.06, respectively) while pre-awake SBP (p = 0.09) along with daytime SBP and DBP load (p = 0.07 and p = 0.06, respectively) were also almost decreased. Conclusions SBG block might be a promising, non-invasive, safe, painless and easy to perform therapeutic option of BP decrease. As with renal denervation, SBG should be effective in those hypertensive patients with an activated SNS, so a period of patient selection should precede the application of this procedure.