Freebase(0.00 / 0 votes)Rate this definition: Chronotropic. Chronotropic effects are those that change the heart rate. Chronotropic drugs may change the heart rate by affecting the nerves controlling the heart, or by changing the rhythm produced by the sinoatrial node. Positive chronotropes increase heart rate; negative chronotropes decrease heart rate.
Erectile dysfunction (ED), formerly known as impotence, is the inability to achieve or maintain an erection long enough to engage in sexual intercourse. Under normal circumstances, when a man is sexually stimulated, his brain sends a message down the spinal cord and into the nerves of the penis.
Affecting an estimated 30 million men in the U.S. alone, ED can be treated orally with what have come to be commonly-known medications such as Viagra, Cialis, Levitra and now Stendra â the first erectile dysfunction drug FDA-approved in 10 years.