Prognostic Value of a Very Prolonged Asystole during Head-Up Tilt Test.
BACKGROUND
Clinical significance and prognosis of a cardioinhibitory response to head-up tilt (HUT) test with a very prolonged asystole (≥30 seconds) is poorly studied. Our aim was to evaluate the treatment (including pacemaker implantation) and prognosis (syncope recurrence, syncope-related trauma, and overall mortality) of patients with a very prolonged asystole on a HUT test.


RESULTS
A retrospective study was conducted in two centers between January 2003 and December 2013 and included a total of 2,263 consecutive HUT tests (sensitized with isosorbide dinitrate) performed in 2,247 patients with syncope of unknown etiology. Cardioinhibitory response with asystole was observed in 149 (6.6%) of these tests (44.3% women, mean age 37 ± 18 years old, 16.1% in the nonpharmacological phase), with a median duration of asystole of 10 (6-19) seconds. Very prolonged asystole (≥30 seconds) was documented in 11 (0.5%) patients (45% women; mean age 40 ± 19 years; only one in the nonpharmacological phase, 9 minutes after HUT). The longest pause lasted 63 seconds. In all patients, avoidance of triggering factors and physical counterpressure maneuvers were recommended. Telephone follow-up was performed: in one patient, fludrocortisone was started; tilt training was conducted in one patient and none received a pacemaker. After a median follow-up of 42 (30-76) months, four patients (36%) had syncopal recurrences, one patient had a syncope-related injury (scalp laceration), and no patient died.
Arrhythmology Unit, Hospital de Santa Cruz, Carnaxide, Portugal.
Maria Salomé
MS
Carvalho
Cardiac Rhythm Unit, Hospital da Luz, Lisboa, Portugal.
Katya
K
Reis Santos
Arrhythmology Unit, Hospital de Santa Cruz, Carnaxide, Portugal.|Cardiac Rhythm Unit, Hospital da Luz, Lisboa, Portugal.
Pedro
P
Carmo
Arrhythmology Unit, Hospital de Santa Cruz, Carnaxide, Portugal.|Cardiac Rhythm Unit, Hospital da Luz, Lisboa, Portugal.
Diogo
D
Cavaco
Cardiac Rhythm Unit, Hospital da Luz, Lisboa, Portugal.
Leonor
L
Parreira
Arrhythmology Unit, Hospital de Santa Cruz, Carnaxide, Portugal.
Francisco
F
Morgado
Arrhythmology Unit, Hospital de Santa Cruz, Carnaxide, Portugal.|Cardiac Rhythm Unit, Hospital da Luz, Lisboa, Portugal.
Pedro
P
Adragão
D000328:Adult; D000368:Aged; D005260:Female; D006323:Heart Arrest / Q000401:mortality*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012189:Retrospective Studies; D013575:Syncope / Q000175:diagnosis / Q000401:mortality*; D018667:Tilt-Table Test; D055815:Young Adult
head-up tilt test; prognosis; syncope; tilt induced-asystole