Previous studies have proposed that
sodium supplement to nonionic
contrast media (CM) can decrease the risk of
ventricular fibrillation (VF). This study was designed to compare the occurence of VF induced by
ioxilan (containing 9 mmol/LNa+) with other nonionic CMs. After wedging a
catheter in the right coronary artery, test solutions including
ioxilan,
ioversol,
iomeprol, and
iopromide were infused for 30 sec at the rate of 0.4 ml/sec or until VF occurred. Then, incidence of VF, contact time (i.e. the time required to produce VF), and QTc were measured. Also, the CMs other than
ioxilan were investigated at
sodium levels adjusted to 9 and 20 mmol/L Na+. The incidence of VF with
ioxilan (0%) was the lowest of all. In the other CMs, the incidence decreased in accordance with increase of
sodium.
Iomeprol and
iopromide showed significant reduction of VF incidence at the
sodium level of 20 mmol/L. The higher
sodium supplements also prolonged the contact times. The increase of QTc was the greatest in
ioxilan.
Ioxilan has the least arrythmogenic property among the current low-osmolality nonionic CMs. This property might be attributable to an optimal
sodium concentration of 9 mmol/L in the CM.