Cardiac Uses of Phosphodiesterase-5 Inhibitors

Bryan G. Schwartz, MD; Laurence A. Levine, MD; Gary Comstock, MD; Vera J. Stecher, PhD; Robert A. Kloner, MD, PhD


J Am Coll Cardiol. 2012;59(1):9-15. 

In This Article


Effects of PDE5I on systemic vascular resistance might be useful for treating patients with hypertension. This was investigated in 25 patients with untreated hypertension randomized to placebo or sildenafil 50 mg 3× daily.[41] Sildenafil decreased average daytime blood pressure (by –8/–6 mm Hg) and clinic blood pressure (by –5/–5 mm Hg).[41] Numerous studies of PDE5Is in a variety of patients generally reported only small reductions in blood pressure (Table 3).[1] In most healthy subjects, blood pressure returned to baseline values within 6 h of sildenafil administration,[42] so multiple daily dosing would be necessary and would not cover the morning rise in blood pressure. Longer-acting tadalafil decreased diastolic blood pressure for 12 h but did not affect systolic blood pressure in healthy volunteers.[43]

Although PDE5Is are contraindicated with any nitrate medication, because of potentially severe hypotension, this drug combination might be beneficial for patients with treatment-resistant hypertension and was investigated in a crossover trial including 6 such subjects continued on their previous medications.[44] Compared with sildenafil alone and with isosorbide mononitrate alone, the combination of sildenafil and isosorbide mononitrate produced the largest blood pressure decrease (placebo-subtracted maximum decrease –26/–18 mm Hg) without significant side effects.[44] The combination of PDE5Is and nitrates requires further investigation to ensure safety.