8498 Nicardipine: Safe and Effective in Treating Catecholamine-Induced Hypertension?

Abstract Disclosure: M. Nazari: None. R. Hasan: None. T. Prodanov: None. K. Charles: None. A. Jha: None. A. Park: None. S. Talvacchio: None. A. Derkyi: None. M. Kuo: None. M. Patel: None. A. Dey: None. A.S. Alzahrani: None. K. Pacak: None. Background: Catecholamine-induced hypertension (HTN), such as that arising from pheochromocytomas and paragangliomas (PCC and PGL, collective PPGLs), is commonly treated with alpha-adrenoceptor or calcium channel blocking agents. Nevertheless, when HTN must be treated more acutely with intravenous (IV) agents, IV alpha-adrenoceptor blocking agents (e.g., IV phentolamine) may have limited availability, prohibitive cost, or be unfamiliar to providers in certain settings. In contrast IV nicardipine, a calcium channel blocking agent, is more widely available, affordable, and oftentimes more familiar among providers; however, its use in acute settings to treat catecholamine-induced HTN is currently limited. Methods: Fourteen PPGL patients with HTN treated with IV nicardipine were identified by retrospective chart review. Safety and efficacy were evaluated and are presented herein. Results: The mean age was 49.6 years old and 50% of patients were female, 21% were current smokers, none had severe hyperlipidemia (LDL 190 mg/dL), 28.6% had diabetes, and 14.3% had a prior major adverse cardiovascular event (MACE; both stroke). Most patients had elevated plasma metanephrines (mean plasma metanephrine 3.5 times the upper reference limit, URL; mean normetanephrine 106.2 times the URL). The majority of patients had PGLs (64.3%) and/or metastatic disease (85.7%). Genetic testing performed in 13 patient was negative in 46% (n=6/13), and an SDHx 46% (n=6/13) or HIF2A (8%, n=1/13) pathogenic variant in the remaining patients. The 14 patients in this study experienced 31 separate hypertensive episodes (e.g., some patients were treated with nicardipine multiple times at our institution) requiring treatment with IV nicardipine with 1108 total hours of observation (mean 79.1 hours/patient) at an average dose of 3.8 mg/hour of nicardipine. A goal mean arterial pressure reduction of 25% within the first 24 hours was achieved in all (100%) patients with treatment complications encountered in 14% (n=2, both with acute heart failure in the setting of catecholamine-induced HTN, not a consequence of nicardipine). One patient (7%) died within 30 days of nicardipine treatment due to post-operative hemorrhage while one patient succumbed to metastatic disease within 90 days of treatment (7%)—neither directly attributable to IV nicardipine use. Discussion/Conclusion: IV nicardipine was both safe and effective in treating acute HTN in a small cohort of PPGL patients. With further study, IV nicardipine may prove to be a reasonable alternative to treatment with IV alpha-adrenoceptor blocking agents especially in instances where IV alpha-adrenoceptor blockers have limited availability, familiarity with use, or prohibitive cost. Presentation: 6/1/2024