Reffelmann Thorsten, Kloner Robert A
The Heart Institute, Good Samaritan Hospital, Division of Cardiovascular Medicine, Keck School of Medicine, University of Southern California, 1225 Wilshire Boulevard, Los Angeles, CA 90017-2395, USA.
Expert Opin Drug Saf. 2005 May;4(3):531-40. doi: 10.1517/14740338.4.3.531.
Therapy of erectile dysfunction has been revolutionised in recent years, as specific pharmacological inhibitors of phosphodiesterase 5 (PDE5), such as sildenafil, tadalafil, or vardenafil, were shown to be highly effective in the treatment of erectile dysfunction. They dilate arterial smooth muscle cells of the corpora cavernosa, which express PDE5 abundantly, by inhibiting the breakdown of 3'5'-cyclic guanosine monophosphate. Despite theoretical concerns of a reduced myocardial tolerance to ischaemia or promoting cardiac arrhythmias, randomised trials and retrospective analyses do not support an increased cardiac risk with oral treatment. Therapeutic doses of PDE 5 inhibitors exhibit slight blood pressure lowering effects, and do not appear to compromise coronary blood flow in coronary artery disease. However, the combination of PDE5 inhibitors with any nitric oxide donor is absolutely contraindicated because of potentially life-threatening hypotension. Before prescribing medication for erectile dysfunction, any patient with cardiovascular disease should be evaluated for a potential risk of a cardiovascular event during sexual activity according to the Princeton Consensus Panel. When a stable cardiac condition can be achieved (low risk group), oral treatment for erectile dysfunction may be appropriate.
近年来，勃起功能障碍的治疗发生了变革，因为磷酸二酯酶5（PDE5）的特异性药理抑制剂，如西地那非、他达拉非或伐地那非，已被证明在治疗勃起功能障碍方面非常有效。它们通过抑制3'5'-环磷酸鸟苷的分解，使大量表达PDE5的海绵体动脉平滑肌细胞舒张。尽管理论上担心心肌对缺血的耐受性降低或促进心律失常，但随机试验和回顾性分析并不支持口服治疗会增加心脏风险。治疗剂量的PDE 5抑制剂有轻微的降压作用，且似乎不会损害冠状动脉疾病患者的冠状动脉血流。然而，由于可能会出现危及生命的低血压，PDE5抑制剂与任何一氧化氮供体联合使用是绝对禁忌的。根据普林斯顿共识小组的建议，在为勃起功能障碍患者开处方前，任何患有心血管疾病的患者都应评估其在性活动期间发生心血管事件的潜在风险。当能实现稳定的心脏状况（低风险组）时，口服治疗勃起功能障碍可能是合适的。
