Safety and efficacy of high-dose adenosine-induced asystole during endovascular AAA repair.

PURPOSE

To assess the safety and efficacy of high-dose adenosine administration to increase the precision of endovascular abdominal aortic aneurysm (AAA) repair using a balloon deployed stent-graft.

METHODS

From January 1997 to March 1999, 98 AAA patients (79 men; mean age 71 years, range 62-91) were treated with balloon-expandable stent-grafts under an approved protocol. After placing a temporary transvenous ventricular lead or an external transthoracic pacing electrode, adenosine (24 mg initially) was administered in an escalating dose fashion to induce at least 10 seconds of asystole, during which the proximal stent was expanded.

RESULTS

Adenosine dosages ranged from 24 to 90 mg (median 24 mg). Nine (9.2%) self-limiting cardiac events were observed: 2 (2.0%) episodes of transient myocardial ischemia, 2 (2.0%) cases of atrial fibrillation requiring cardioversion, 1 (1.0%) transient left bundle branch block lasting <10 seconds, and 4 (4.1%) prolonged periods of asystole requiring temporary pacemaker activation. There were no cases of bronchospasm or worsening obstructive pulmonary disease, and no patients required inotropic support after adenosine-induced asystole.

CONCLUSIONS

Cardiac events following adenosine-induced asystole are infrequent, mild, and easily treated. The perioperative use of high-dose adenosine to ensure precise stent-graft placement appears to be a safe method of inducing temporary asystole during endovascular aortic repair.