Inappropriate sinus tachycardia: focus on ivabradine
H S Abed1, J R Fulcher1, M J Kilborn1
1Department of Cardiology, Royal Prince Alfred Hospital and NHMRC Clinical Trials Centre, University of Sydney, Sydney, New South Wales, Australia.
Insights
Inappropriate sinus tachycardia (IST) causes high heart rate without a clear cause, impacting quality of life. Ivabradine shows promise in treating this condition when other therapies fail.
Area of Science:
- Cardiology
- Pharmacology
Background:
- Inappropriate sinus tachycardia (IST) is a poorly understood condition causing elevated heart rate without a physiological stimulus.
- IST significantly impacts patients' quality of life and lacks effective treatments.
- Current treatments like beta-blockers are often ineffective or poorly tolerated.
Purpose of the Study:
- To review the prevalence and mechanisms of inappropriate sinus tachycardia.
- To examine the evidence for the efficacy of ivabradine in treating IST.
Main Methods:
- Literature review of studies on inappropriate sinus tachycardia.
- Analysis of clinical trial data and case reports on ivabradine for IST.
Main Results:
- Ivabradine, a sinus node If funny current inhibitor, effectively reduces heart rate.
- Emerging evidence suggests ivabradine is a promising treatment option for IST.
Conclusions:
- Inappropriate sinus tachycardia requires further understanding of its mechanisms.
- Ivabradine represents a potential new therapeutic avenue for managing IST.
Abstract:
Inappropriate sinus tachycardia (IST) is an incompletely understood condition, characterised by an elevation in heart rate (HR) accompanied by wide ranging symptoms in the absence of an underlying physiological stimulus. The condition often takes a chronic course with significant adverse effects on quality of life. Currently, there is no effective treatment for IST. Beta-blockers, generally considered the cornerstone of treatment, are often ineffective and poorly tolerated. Ivabradine is a novel sinus node If 'funny current' inhibitor, which reduces the HR. It has been approved for the treatment of beta-blocker refractory chronic systolic heart failure and chronic stable angina but more recently has shown promise in the treatment of IST. This review provides an overview of IST prevalence and mechanisms followed by an examination of the evidence for the role and efficacy of ivabradine in the treatment of IST.
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