NCT00865917

Cardiovascular Effects of Selective I(f)-Channel Blockade

Einfluss Selektiver I(f)-Blockade Auf Orthostase-Toleranz Und Sympathikusaktivität Bei Gesunden

• Status: Unknown
• Phase: Phase 2
• Study type: Interventional
• Enrollment: 40 (estimated)
• Sponsor: Hannover Medical School · Academic / Other
• Sex: Male
• Age: 18 Years – 40 Years
• Healthy volunteers: Accepted

Summary

The study compares three treatment modalities in a human model of Postural orthostatic tachycardia syndrome (POTS): beta-blockers, I(f)-blockers, and placebo.

Detailed description

Elevated heart rate may lead to cardiac disease in the long-term. Therefore, drugs lowering heart rate are useful. Beta-blockers are an established treatment modality. They not only lower heart rate but also contractility, which might be undesirable in certain tachycardic disorders. Postural orthostatic tachycardia syndrome (POTS) patients complain about dizziness, weakness, headache, lightheadedness, fatigue, nausea, and presyncope. In some patients there is elevated heart rate even during supine rest. In POTS patients it is preferable to lower heart rate without reducing cardiac contractility which can be achieved by using so-called I(f)-blockers. Thus, they might be superior to beta-blockers in POTS. In our study, we artificially generate POTS in healthy male subjects for about 48 hours. We want to compare the cardiovascular effects and orthostatic tolerance of the following treatments: beta-blocker, I(f)-blocker, and placebo. Moreover, we will quantify changes in cardiovascular autonomic regulation brought about by I(f)-blockade versus placebo.

Conditions

• Postural Orthostatic Tachycardia Syndrome

Interventions

Type	Name	Description
DRUG	beta-blocker (Metoprolol)	Metoprolol 95 mg once per day
DRUG	I(f)-blocker (ivabradine)	ivabradine 7.5 mg once per day
DRUG	Placebo	matching appearance

Timeline

• Start date: 2008-11-01
• Primary completion: 2010-11-01
• Completion: 2010-12-01
• First posted: 2009-03-19
• Last updated: 2009-03-19

Locations

2 sites across 1 country: Germany