A 38-year-old woman who takes verapamil for idiopathic hypertrophic subaortic stenosis (IHSS) is anesthetized with isoflurane, nitrous oxide, oxygen, and fentanyl for laparoscopic cholecystectomy. After inflation of the abdomen with carbon dioxide, heart rate increases to 140 bpm, blood pressure decreases to 85/60 mmHg, and ST-segment depression occurs. End-tidal carbon dioxide concentration is uncharged. Appropriate pharmacologic management includes intravenous administration of:

(1) Phenylephrine
(2) Nitroglycerin
(3) Esmolol
(4) Calcium chloride

This one is a toughie for most (I suspect). Please don't be intimidated. All 'stabs' at the answer are welcomed. Only one answer is correct.

Has anyone encountered an IHSS pt?? What do you know about IHSS??