Can phosphodiesterase inhibitors (PDEIs) be used in a non-diabetic, hypertensive male with coronary artery disease (CAD) and three stents in the right coronary artery (RCA), classified as New York Heart Association (NYHA) Class I, who developed erectile dysfunction (ED) post-surgery for benign prostatic hyperplasia (BPH)?

Can Phosphodiesterase Inhibitors Be Used in This Patient?

Yes, PDE5 inhibitors are appropriate first-line therapy for this patient with NYHA Class I heart failure, controlled hypertension, and stable CAD with successful coronary revascularization (three RCA stents), as he falls into the low cardiovascular risk category where all first-line ED therapies are recommended. 1

Cardiovascular Risk Stratification

This patient meets the low-risk criteria established by the Princeton Consensus Panel for safe use of PDE5 inhibitors 1:

• NYHA Class I heart failure (low-risk; Class II or higher would be high-risk) 1
• Successful coronary revascularization with three stents in RCA 1
• Controlled hypertension (assuming BP is controlled; uncontrolled hypertension would be high-risk) 1
• Asymptomatic coronary artery disease with stable cardiac status 1

The absolute risk of myocardial infarction during sexual activity is extremely low—only 20 chances per million per hour even in post-MI patients 1. Sexual activity increases physical exertion to 3-4 METs, which this patient should tolerate given his NYHA Class I status 1.

Critical Safety Screening Before Prescribing

Absolute contraindications that must be ruled out 1, 2:

• Any form of nitrate use (oral, sublingual, transdermal, or recreational "poppers" containing amyl/butyl nitrite) - this is the most critical contraindication due to potentially fatal hypotension 1, 2
• Guanylate cyclase stimulators (riociguat/Adempas) 2
• Recent MI or stroke (within 2 weeks) 1
• Unstable or refractory angina 1

Functional capacity assessment: Verify the patient can walk 1 mile in 20 minutes or climb 2 flights of stairs without symptoms 1. If unable to perform this level of activity, refer to cardiology before prescribing 1.

Recommended Treatment Approach

Start with oral PDE5 inhibitors as first-line therapy 1:

• Tadalafil 10 mg as-needed OR tadalafil 5 mg daily are both appropriate initial choices 3, 2
• Tadalafil 5 mg daily has the added benefit of treating both ED and BPH symptoms simultaneously, which is FDA-approved and particularly relevant given his post-BPH surgery status 3, 2
• Daily dosing eliminates the need to time medication with sexual activity, providing spontaneity 3

Alternative: Sildenafil 50 mg as-needed if the patient prefers scheduled sexual activity with a more predictable window of action 3

Drug Interaction Considerations

Alpha-blocker interaction (relevant if patient is on alpha-blockers for BPH) 2:

• If taking alpha-blockers, blood pressure could drop suddenly when combined with PDE5 inhibitors 2
• Tadalafil 5 mg daily can replace alpha-blocker therapy for BPH symptoms 3, 2

Antihypertensive medications: PDE5 inhibitors have additive blood pressure-lowering effects with antihypertensive medications, but this is generally well-tolerated in stable patients 1, 4

Optimizing Treatment Success

An adequate trial requires at least 5 separate attempts at maximum tolerated dose before declaring treatment failure 3. Common reasons for apparent failure include 3:

• Lack of sexual stimulation (PDE5 inhibitors require sexual arousal to work) 3
• Taking medication with large or fatty meals (reduces absorption) 3
• Heavy alcohol use (impairs erectile function independently) 3
• Inadequate dose or insufficient attempts 3

If initial dose is ineffective but well-tolerated, increase to tadalafil 20 mg as-needed or continue tadalafil 5 mg daily for at least 4-8 weeks before assessing response 3, 2.

Special Considerations for Post-BPH Surgery ED

Post-surgical ED may improve over time as nerve recovery occurs, but PDE5 inhibitors remain effective treatment 3. Men post-prostatectomy have more severe ED at baseline and may respond less robustly, making adequate trial duration particularly important 3.

Consider testosterone screening: Check total testosterone levels, as testosterone deficiency is common in men with cardiovascular disease and combining PDE5 inhibitors with testosterone replacement is more effective than either alone in hypogonadal men 1, 3.

Emergency Nitrate Protocol

If emergency nitrates are needed 1, 3:

• Wait at least 24 hours after sildenafil before administering nitrates 1
• Wait at least 48 hours after tadalafil before administering nitrates 1, 3
• This must be done under close medical supervision with continuous monitoring 1

Common Pitfalls to Avoid

Do not declare treatment failure prematurely: Up to 30% of apparent non-responders become successful responders after proper counseling on technique, timing, and completing an adequate trial of at least 5 attempts 3.

Do not assume all antihypertensive medications worsen ED equally: Beta-blockers (especially older agents) and thiazide diuretics are more likely to cause ED than angiotensin receptor blockers or nebivolol 1, 5. However, with PDE5 inhibitors available, drug class distinctions for ED are less relevant 1.

Do not overlook relationship or psychological factors: Depression, anxiety, and relationship conflict significantly impact treatment response and should be addressed 3.