Clinical improvement in patients with orthostatic intolerance after treatment with bisoprolol and fludrocortisone

Abstract

Orthostatic intolerance is the development of disabling symptoms upon assuming an upright posture that are relieved partially by resuming the supine position. Postural tachycardia syndrome (POTS) is an orthostatic intolerance syndrome characterized by palpitations because of excessive orthostatic sinus tachycardia, lightheadedness, tremor, and near-syncope. Patients usually undergo extensive medical, cardiac, endocrine, neurologic, and psychiatric evaluation, which usually fails to identify a specific abnormality. The authors investigated the autonomic and hemodynamic profile of patients with POTS and the effectiveness of bisoprolol and fludrocortisone. The authors evaluated 11 female patients with POTS before and after medical treatment with a cardioselective bisoprolol beta-blocker or fludrocortisone, or both, and 11 age-matched control patients. Variability of heart rate and systolic blood pressure was assessed by fast Fourier transform, and spontaneous baroreceptor gain was assessed by use of the temporal sequences slope and alpha index. Modelflow was used to quantify hemodynamics. Symptoms in all patients improved greatly after medication. The autonomic and hemodynamic impairment observed in patients with POTS, particularly after orthostatic stress, is treated effectively with bisoprolol or fludrocortisone or both. These results need further confirmation in a controlled double-blind study. Proper medical treatment improves dramatically the clinical and autonomic-hemodynamic disturbances observed in patients with POTS. The data support the hypothesis that POTS is the result of a hyperadrenergic activation or hypovolemia during orthostasis.

Long-term follow-up of patients with postural tachycardia syndrome

“…Although selective beta1-adrenoreceptor blockade has been reported in literature, including our own experience [4], a more recent controlled trial (Raj SR, Circ 2009) showed that low-dose propranolol, a non-selective beta-blocker, may be more appropriate in treatment of POTS. Other recent study (Chen L, Circ J 2011) observed superiority of midodrine against selective beta1-adrenoreceptor blockers in controlling symptoms in these patients.…”

“…Patients' symptoms are usually palpitations, light-headedness and tremor, but syncope can also occur; non-orthostatic symptoms, such as fatigue, migraine and gastrointestinal complaints, are also common [1,3,4]. Symptoms are frequently exacerbated by heat and exercise [2].…”

“…Proper treatment significantly improves autonomic and hemodynamic disturbances, but long-term prognosis remains uncertain [4].…”

Postural Tachycardia Syndrome: A Heterogeneous and Multifactorial Disorder

“…Drug therapy of POTS includes the mineralocorticoid fludrocortisone 90 to promote intravascular volume expansion, the ␣ 1 -adrenergic agonist midodrine 87,91 to elicit peripheral vasoconstriction and reduce venous pooling, ␤-blockers including propranolol 87,92 and cardioselective agents such as bisprostol 90,93 to control the excessive sinus tachycardia, and the cholinesterase inhibitor pyridostigmine [94][95][96] to prolong the phasic effects of acetylcholine on the autonomic ganglia, leading to peripheral sympathetic vasoconstrictor output (and potentiating vagal effects) on standing (Table 3). However, adverse effects of these drugs can limit their use in patients with POTS because of the presence of comorbid symptoms.…”

Acetylcholinesterase Inhibition Improves Tachycardia in Postural Tachycardia Syndrome

“…2 Patients with POTS often have an exaggerated increase in plasma norepinephrine on standing. 3 This finding has driven a focus on primarily sympatholytic therapeutic strategies with central 4 or peripheral 5 targeting, or secondarily by increasing peripheral resistance 6 or by blood volume expansion. 5 There are no data addressing the alternative strategy of controlling heart rate by augmenting cardiovagal tone.…”