Aim: To determine the possibilities of nocturnal penile tumescence (NPT) monitoring in the detection of coronary heart disease (CHD).
Materials and methods: A total of 100 patients were included in the study, of them 50 men had a confirmed diagnosis of CHD and 50 patients consisted the control group. In all patients, flow-dependent vasodilation of the brachial artery and pulse wave velocity were evaluated. The assessment of the quality of erection was carried out using IIEF-15 questionnaire (erectile domain) and Androscan NPT monitoring device. The relative increase in the diameter of the penis (rIn), the duration of NPT with rIn greater than or equal to 30% and 20%, respectively (dNPT with rIn more or equal 30% and dNPT with rIn more or equal 20%) were estimated.
Results: The age of the patients in both groups was comparable with a median of 58.0 years. Patients with CHD had a higher body mass index (BMI) than patients without CHD (29.2 kg/m2 vs. 26.9 kg/m2, respectively; p=0.011). In those without CHD, erectile function was better, both according to the IIEF-15 questionnaire and according to the monitoring of NPT. The model with the maximum coefficient of determination (R2 =32.1%) predicting the probability of having CHD included age, BMI, rIn and dNPT with rIn more or equal 20%. The chance of having CHD increased by 10.5% and 1.6% with a decrease in rIn by 1% and a decrease in dNPT with rIn more or equal 20% for 1 minute. The sensitivity and specificity of the model was 74% and 65.3%, respectively.
Conclusion: Monitoring of the NPT is an important tool for the diagnosis of vascular ED. Based on the results, it is possible to assess the probability of CHD. In contrast to the IIEF-15 questionnaire, NPT, dNPT with rIn more or equal 20% and rIn are more likely to suggest the presence of CHD. The lower the OP and dNPT with rIn more or equal 20%, the higher the probability of having CHD.
Keywords: coronary artery disease; duration of nocturnal penile tumescence; erectile dysfunction; monitoring of nocturnal penile tumescence; relative increase in penile diameter.