[2] IST symptoms include palpitations, chest discomfort, exhaustion, shortness of breath, presyncope, and syncope.

Treatments in the form of pharmacological therapy or catheter ablation are available, but the condition is currently difficult to treat successfully.

Other symptoms include chest pain, fatigue, shortness of breath, presyncope, syncope,[1] reduced exercise tolerance, anxiety, panic attacks, and headaches.

At rest, the sinus node is primarily regulated by tonic and phasic parasympathetic activation in normal, healthy individuals.

Invasive testing, such as electrophysiology studies, are not helpful in making the diagnosis, but they may be useful in ruling out a concomitant supraventricular tachycardia mechanism.

POTS syndromes and inappropriate sinus tachycardia may overlap, raising the possibility of shared mechanisms.

[7] Managing inappropriate sinus tachycardia, controlling symptoms and decreasing rate, remains a significant challenge, especially given the ambiguity of the syndrome itself.

[3] In most patients, sleeping with the head of the bed elevated and increasing plasma volume through generous salt and fluid intake can be beneficial with minimal risk.

[15] Pharmacologic therapy for Inappropriate sinus tachycardia patients should be started gradually, with the goal of lowering HR and improving symptoms.

Patients with β-adrenergic receptor sensitivity and elevated catecholamine levels throughout orthostatic stress usually respond well to a variety of β-blockers.

Nondihydropyridine calcium channel blockers have demonstrated a modest benefit in symptom control of IST in patients with contraindications to β-blockers.

There have been no randomized controlled trials regarding the use of these drugs in the treatment of Inappropriate sinus tachycardia, and all, with the possible exception of β-blockers, should be considered off-label indications.

Ivabradine shows great promise as the possible therapy of choice for beta-blocker intolerant or suboptimally responsive patients with a chronic condition that frequently becomes clinically problematic in management.

[16] There are no specific guidelines in place to determine which patients with inappropriate sinus tachycardia should be considered for invasive treatments.

There is also no consensus on the best approach, which includes modifications or ablation, open chest versus conventional intravascular access, and mapping methods.

[2] Inappropriate sinus tachycardia was previously thought to be a rare condition affecting young women, with health professionals being overrepresented.