Can We Cure Erectile Dysfunction?

Abstract

The treatment of erectile dysfunction (ED) has been revolutionized during the last two decades. Several treatment options are available today, including phosphodiesterase type 5 inhibitors (PDE5-Is), intracavernosal injections, and penile prostheses. Despite the efficacy and safety profiles of current treatments, most men with ED are treated with no cause-specific treatment options. ED is potentially reversible or curable only in a small proportion of carefully selected patients [1], including those with specific endocrinopathies (eg, hypogonadism, hyperprolactinemia), trauma-associated ED that may be amenable to reconstructive microvascular surgery in selected cases, specific medications (eg, antihypertensives, antidepressants, antiandrogens, recreational drugs), and lifestyle and psychosocial factors that can be potentially modified. Gene therapy has the potential to become a viable future curative treatment option, but only sparse data exist. Finally, the long-term daily use of PDE5-Is has been shown to induce a short-term improvement of erectile function, probably due to the improvement of the endothelial function, but data are very limited [2–4]. Extracorporeal shock wave lithotripsy (ESWL) is a wellestablished treatment modality for urinary stones that has been applied in clinical practice for about 20 yr. It has been also studied in other fields of medicine, including the treatment of Peyronie disease, chronic diabetic foot ulcers, and wound healing after vein harvesting for coronary artery bypass surgery, as well as in some orthopedic conditions, including plantar fasciitis, Achilles tendonitis, and tennis elbow. The effectiveness is debatable in most of these conditions, and currently ESWL is not an established treatment. Another field of research on ESWL in medicine includes several cardiologic conditions. Some preliminary data show that ESWL could enhance the expression of vascular endothelial growth factor and its receptor Flt-1 that promote neovascularization. ESWL may have a positive influence on both the proliferation and the differentiation of cardiomyocytes, smooth muscle, and endothelial cell precursors that could inhibit or retard the pathologic remodeling and functional degradation of the heart if applied during the early stages of heart failure, representing a noninvasive therapeutic strategy for ischemic heart disease [5,6]. Because ED is a disease of the endothelium, it seems reasonable to consider ESWL in the treatment of this condition. The authors ‘‘transfer’’ data from the cardiovascular system to the cavernosal tissue and present a proof-ofconcept study in 20 men with vasculogenic ED [7] .T hey delivered low-intensity shockwaves in five parts of the penis including the crura (two sessions per week for 3 wk repeated after a no-treatment interval of 3 wk). Erectile function (assessed by the International Index for Erectile Function– Erectile Dysfunction [IIEF-ED] domain score) improved significantly after 1 mo, and this improvement was maintained during the 6-mo follow-up. Similarly, the duration of erections and penile rigidity (assessed by nocturnal penile tumescence and rigidity recordings) improved significantly as well as the scores of several other questionnaires used in the study (rigidity score, Quality of Erection Questionnaire, and Self-Esteem and Relationship Questionnaire). The endothelial function (assessed by the flow-mediated dilatation technique) improved significantly with a strong correlation between the IIEF-ED domain scores and the changes in endothelial function parameters. Another important result was the fact that 50% of these patients had spontaneous erections sufficient for vaginal penetration without PDE5-I support, and the treatment satisfaction rates were high (assessed by the Erectile Dysfunction Inventory of Treatment Satisfaction). Finally, the treatment was well tolerated. No pain or other adverse events were reported during follow-up.