Objective : To study the ambulatory blood pressure profile of paediatric pateints with vasovagal syncope and assess its role in the diagnosis of vasovagal syncope.
Methods: This study was done in a tertiary Paediatric referral centre in Hong Kong. Patients with recurrent syncope confirmed to be vasovagal in origin by tilt table test were recruited. Ambulatory blood pressure monitoring was done after tilt test.
Results: 40 patients were recruited between 2005 to 2007. Male to Female ratio was 10:30. The mean age was 15.7 year(range 9-22.5). Blood pressure result was interpreted with reference to data by Soergel etal. Several interesting findings were noted. 68%(12-100%) and 39%(37-100%) of daytime systolic blood pressure readings were less than the 50 and 10 centile age reference. 76%(37-100%) and 42% (5-86%)of daytime diastolic pressure readings were less than the 50 and 10 centile age reference. The mean systolic blood pressure load was 2.5% (range 0-24% with 27 patients having 0%)and the mean diastolic pressure load was 3.6% (range 0-21% with 21 patients having 0%). The daytime systolic and diastolic blood pressure range were 34.7mmHg(range 17-61mmHg) and 30.5mmHg(range 12-64mmHg) respectively. With the use of event recording and patient-triggered instantaneous blood pressure measurement during dizziness and presyncope, vasovagal syncope could be diagnosed in a more physiological way.
Conclusion: Ambulatory blood pressure monitoring is a useful tool in diagnosing vasovagal syncope.