Erection is a vascular event. The penis becomes rigid when blood flow to the corpora cavernosa increases sixfold and venous outflow is physiologically impeded. Penile perfusion is governed by three organ systems—the neurologic, circulatory, and endocrinologic systems—each necessary for potency. The neurologic system accounts for vasodilation and venoconstriction of the corporal blood vessels so that blood is shunted to the erectile tissues; the circulatory system provides adequate blood flow to the hypogastric-cavernous bed, a distal branch off the internal iliac vessels; and the endocrine system, mediated by testosterone, plays a permissive role through mechanisms that have yet to be elucidated.
There are treatments available to help you to get and maintain an erection. In addition, making healthy changes to your lifestyle could help with impotence. Switching to a healthier balanced diet, taking more exercise and cutting down on or giving up alcohol and cigarettes could help you to see an improvement in sexual function. If you think that the problem may be related to stress or anxiety, counselling can also help.
Watts and coworkers, in their review article, make several points about this ED/CAD nexus. Endothelial dysfunction is present in both CVD and ED, and is linked through the NO mechanism. The authors note that PDE5 inhibitors improve endothelial function and have a salutary effect on both CVD and ED. Both ED and cardiac disease respond to modifications in lifestyle as well as pharmacologic manipulation. These authors also report that the presence of ED gives the clinician an opportunity to assess CVD and prevention as well.20
The causes of erectile dysfunction include aging, high blood pressure, diabetes mellitus, cigarette smoking, atherosclerosis (hardening of the arteries), depression, nerve or spinal cord damage, medication side effects, alcoholism or other substance (drug) abuse, pelvic surgery including radical prostatectomy, pelvic radiation, penile/perineal/pelvic trauma such as pelvic fracture, Peyronie's disease (a disorder that causes curvature of the penis and sometimes painful erections), and low testosterone levels.
Qaseem, A., Snow, V., Denberg, T. D., Casey, D. E., Forciea, M. A., Owens, D. K., & Shekelle, P. (2009). Hormonal testing and pharmacologic treatment of erectile dysfunction: A clinical practice guideline from the American College of Physicians. Annals of internal medicine, 151(9), 639-649. Retrieved from http://annals.org/aim/article/745155/hormonal-testing-pharmacologic-treatment-erectile-dysfunction-clinical-practice-guideline-from