Ivabradine in treatment of sinus tachycardia mediated vasovagal syncope.
OBJECTIVE
Ivabradine, an I(f) current blocker, has shown promising results in treatment of postural orthostatic tachycardia syndrome (POTS). There is a subgroup of vasovagal syncope (VVS) patients, who demonstrate sinus tachycardia before collapse on tilt testing mimicking some features of POTS. These patients may also respond to ivabradine therapy. University Hospital Syncope Clinic where ivabradine was prescribed in a prospective fashion on humanitarian grounds between October 2008 and December 2011.


RESULTS
Twenty-five patients of mean age 33±years presenting syncope in all and palpitation in 23, duration 9±years underwent tilt testing with reproduction of usual symptoms including tachycardia preceding collapse. Ivabradine was prescribed in doses of 5-20 mg/day, mean 10.7 mg, as once or twice daily medication. The response to treatment was classified as deterioration in none, no change in 5, improvement in 10, and symptoms abolished in 8 patients. Side effects were minimal; one patient required discontinuation.


CONCLUSIONS
In this pilot study of ivabradine, in patients with VVS, of patients who demonstrated sinus tachycardia before collapse on tilt, 72% reported a marked benefit or complete resolution of symptoms. The drug was well tolerated. A randomized controlled trial against placebo is justified.
St Mary's Hospital, Imperial College Healthcare NHS Trust, London, UK.
Richard
R
Sutton
Tushar V
TV
Salukhe
Ann-Christine
AC
Franzen-McManus
Andrea
A
Collins
Phang Boon
PB
Lim
Darrel P
DP
Francis
D000293:Adolescent; D000328:Adult; D000368:Aged; D000889:Anti-Arrhythmia Agents / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D001552:Benzazepines / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D004334:Drug Administration Schedule; D005260:Female; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D000077550:Ivabradine; D008131:London; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D019462:Syncope, Vasovagal / Q000175:diagnosis / Q000188:drug therapy* / Q000209:etiology / Q000503:physiopathology; D013616:Tachycardia, Sinus / Q000150:complications / Q000175:diagnosis / Q000188:drug therapy* / Q000503:physiopathology; D018667:Tilt-Table Test; D013997:Time Factors; D016896:Treatment Outcome; D055815:Young Adult
D000889:Anti-Arrhythmia Agents; D001552:Benzazepines; D000077550:Ivabradine
Ivabradine; Postural orthostatic tachycardia syndrome; Syncope Clinic; Tilt testing; Vasovagal syncope