Milestone Pharmaceuticals Inc. (MIST) has received for its first commercial product, CARDAMYST nasal spray, for the conversion of acute symptomatic episodes of paroxysmal supraventricular tachycardia to sinus rhythm in adults.Paroxysmal supraventricular tachycardia, caused by an abnormality in the electrical system of the heart, affects more than two million Americans. People with this condition experience unexpected episodes of rapid heart rate, ranging from 160 to 220 beats per minute or sometimes exceed ...