Inappropriate sinus tachycardia. Diagnosis and treatment.

Inappropriate sinus tachycardia is characterized by consistently elevated heart rates and exaggerated responses to minimal physiologic activity. The syndrome of inappropriate sinus tachycardia is defined by the clinical presentation of palpitations and presyncope that commonly appear to be out of proportion to the severity of the tachycardia. The development of a potentially curative procedure for patients suffering from inappropriate sinus tachycardia has renewed interest in the treatment of such patients. Continued research directed at the pathophysiology of inappropriate sinus tachycardia and what the optimal end point for achieving adequate rate control by radiofrequency catheter ablation without the need for the implantation of a permanent pacemaker is required. The optimal treatment may be the use of drugs that specifically inhibit sinus node pacemaker current.