Q: 74 year old with previous history of CHF developed atrial fibrillation with RVR (rapid ventricular rate) pre-operatively which was controlled with IV cardizem drip. Cardizem was continued. Patient developed signs and symptoms of Malignant Hyperthermia during surgery. IV dantrolene was administerated. Patient became hypotensive, developed V.Tach., collapsed and died?



Answer: Calcium channel blockers such as diltiazem (Cardizem) or verapamil may cause severe hemodynamic problems if concomittently administerated with Dantrolene. It may lead to severe cardiovascular collapse, arrhythmias, myocardial depressions, and hyperkalemia.