OBJECTIVES: This explorative substudy aimed at determining the effect of
inhaled xenon on left ventricular function by echocardiography in comatose survivors
of out-of-hospital cardiac arrest.
DESIGN: A randomized two-group single-blinded phase 2 clinical drug trial.
SETTING: A multipurpose ICU in two university hospitals.
PATIENTS: Of the 110 randomized comatose survivors after out-of-hospital cardiac
arrest with a shockable rhythm in the xenon in combination with hypothermia
after cardiac arrest trial, 38 patients (24–76 yr old) with complete echocardiography
were included in this study.
INTERVENTIONS: Patients were randomized to receive either inhaled xenon
combined with hypothermia (33 C) for 24 hours or hypothermia treatment alone.
Echocardiography was performed at hospital admission and 24 4 hours after
hypothermia.
MEASUREMENTS AND MAIN RESULTS: Left ventricular ejection fraction,
myocardial longitudinal systolic strain, and diastolic function were analyzed
blinded to treatment. There were 17 xenon and 21 control patients in whom echocardiography
was completed. Clinical characteristics did not differ significantly
between the groups. At admission, ejection fraction was similar in xenon and control
patients (39% 10% vs 38% 11%; p = 0.711) but higher in xenon than
control patients after hypothermia (50% 10% vs 42% 10%; p = 0.014).
Global longitudinal systolic strain was similar in xenon and control patients at
admission (–9.0% 3.8% vs –8.1% 3.6%; p = 0.555) but better in xenon
than control patients after hypothermia (–14.4.0% 4.0% vs –10.5% 4.0%;
p = 0.006). In patients with coronary artery disease, longitudinal strain improved in
the nonischemic myocardial segments in xenon patients. There were no changes
in diastolic function between the groups.