Author + information
- Received January 19, 2012
- Revision received July 19, 2012
- Accepted July 31, 2012
- Published online February 26, 2013.
- ↵⁎Reprint requests and correspondence:
Dr. Brian Olshansky, Department of Medicine, University of Iowa Hospitals and Clinics, 4426a JCP, 200 Hawkins Drive, Iowa City, Iowa 52242
Inappropriate sinus tachycardia (IST) is a syndrome in which the sinus heart rate is inexplicably faster than expected and associated symptoms are present. The heart rate at rest, even in a supine position, can exceed 100 beats/min; minimal activity accelerates the rate rapidly and substantially. Patients with IST may require restriction from physical activity. Mechanisms responsible for IST are understood incompletely. It is important to distinguish IST from so-called appropriate sinus tachycardia and from postural orthostatic tachycardia syndrome, with which overlap may occur. Because the long-term outcome seems to be benign, treatment may be unnecessary or may be as simple as physical training. However, for patients with intolerable symptoms, therapeutic measures are warranted. Even at high doses, β-adrenergic blockers, the first-line therapy, often are ineffective; the same is true for most other medical therapies. In rare instances, catheter- or surgically- based right atrial or sinus node modification may be helpful, but even this is fraught with limited efficacy and potential complications. Overtreatment, in an attempt to reduce symptoms, can be difficult to avoid, but is discouraged.
Dr. Olshansky is a consultant for Boston Scientific, Medtronic, BioControl, Sanofi-Aventis, Boehringer Ingleheim, and Amarin. The income derived from each of these companies is separately < $10,000. Dr. Sullivan has reported that she has no relationships relevant to the contents of this paper to disclose.
- Received January 19, 2012.
- Revision received July 19, 2012.
- Accepted July 31, 2012.
- American College of Cardiology Foundation
- What Is a Normal Sinus Rate?
- Inappropriate Sinus Tachycardia: The Clinical Presentation
- Epidemiology of Inappropriate Sinus Tachycardia
- Regulation of the Sinus Rate
- Mechanisms Responsible for Inappropriate Sinus Tachycardia
- Animal Models
- Clinical Studies
- Causes for Sinus Tachycardia
- Diagnosing Inappropriate Sinus Tachycardia
- Treatment of Inappropriate Sinus Tachycardia
- Radiofrequency Catheter Ablation
- Surgical Ablation
- Emerging Therapy for Inappropriate Sinus Tachycardia
- A General Approach