<prompt> Use of Phosphodiesterase Inhibitors for erectile Dysfunction is contraindicated in:Pulmonary Aerial HypeensionUnstableSymptomatic AnginaPrevious MI 6 weeks agoCHF NYHA Class-I  <response>: Unstablesymptomatic angina represents a High-Risk patient category Princeton Guidelines where phosphodiesterase inhibitors are contraindicated. Previous MI 6weeks ago represents a low risk category as does CHF NYHA Class-I. Such patients may be initiated on a Phosphodiesterase inhibitor. Low-risk patients can initiate or resume sexual activity and begin Erectile Dysfunction treatment without fuher testing or evaluation. The PDE5 inhibitors Sildenafil, Tadalafil and vardenafil may be used to treat erectile dysfunction ED in low risk individual. Sexual Inquiry Erectile Dysfunction: Clinical Evaluation for Risk Stratification: Cardiovascular risk factors are known to be associated with the presence pf erectile dyfunction ED, and ED is more common in men with cardiovascular disease CVD The Princeton Guidelines provide a strategy for assessing cardiac risk and planning a safe return to sexual activity. Low Risk Intermediate Risk High Risk Asymptomatic 3 coronary risk factors excluding gender Controlled hypeension Mild, stable angina Post-successful coronary revascularization Uncomplicated previous MI 6-8 weeks Mild valvular disease LVDCHF NYHA Class I major coronary risk factors excluding gender Moderate, stable angina Recent MI 2, 6 weeks LVDCHF NYHA Class II Non-cardiac atherosclerotic diseases, such as CVA, PVD Unstable or refractory angina Uncontrolled hypeension LVDCHF NYHA Class IIIIV Recent MI or CVA 2 weeks High-risk arrhythmias Hyperophic obstructive and other cardiomyopathies Moderatesevere valvular disease Ref: The Second Princeton consensus on sexual dysfunction and cardiac risk; new guidelines for sexual medicine 