Significant arrhythmias associated with Interleukin-2 therapy

Abstract

2588 Background: A side effects of Interleukin-2 (IL-2) is the vascular leak syndrome. High dose IL-2 produces a reduction of mean arterial pressure and systemic vascular resistance as well as increased heart rate and cardiac output similar to early septic shock. Cardiac arrhythmias have been reported in 14–21% of the patients undergoing IL-2 therapy. Methods: A retrospective study of 92 patients treated at OLMMC with IL-2 for renal cell carcinoma and or melanoma in 2003was done. Patients age ranged from 24 to 74 years (mean of 56 years). Eligibility criteria included normal left ventricular systolic function, normal pulmonary function tests, normal stress test (no evidence of cardiac ischemia), normal renal function, resected locally advance or metastatic renal cell carcinoma, no prior systemic therapy and excellent organ function. All patients treated with IL-2 either high dose or intermediate dose were monitored. EKGs performed before initial infusion demonstrated normal sinus rhythm. Results: Patients included 52 male (56.6%) and 40 females (43.4%). Ten male and eight female patients developed cardiac arrhythmias. Eight patients had AF (8.7%), 8 patients had narrow complex supraventricular tachycardia (8.7%), 2 patients had ventricular tachycardia (0.2%). AF was treated with iv and/or po diltiazam. SVT was treated with iv diltiazem and digoxin; VT was treated with iv procainamide, diltiazam and digoxin. All arrhythmias resolved. Among the 15 patients treated with high dose IL-2, 6 (6.5%) developed AF, 2 (0.2%) developed VT, and 7 (46.6%) developed SVT. Two patients treated with intermediate dose IL-2 developed AF, and 1 developed SVT. The most striking electrolyte imbalances were hyperkalemia and hypercalcemia, although below parameters for arrhythmias. Conclusions: 19.56% of patients treated with iv IL-2 showed significant cardiac arrhythmias that necessitated iv and po management. Several patients required po treatment at home, especially the patients with AF. The patients with AF responded to diltiazem with no need for long-term anticoagulation with warfarin. The VT resolved without sequelae. Despite careful cardiac pre-screening, IL-2 can induce Arrythmias thru physiologic pathways. Therefore, cardiac monitoring continues to be necessary. Author Disclosure Employment or Leadership Consultant or Advisory Role Stock Ownership Honoraria Research Funding Expert Testimony Other Remuneration Chiron Chiron Chiron