The application of digital pulse amplitude tonometry to the diagnostic investigation of endothelial dysfunction in men with erectile dysfunction

The application of digital pulse amplitude by fingertip peripheral arterial tonometry (PAT) device in patients with erectile dysfunction (ED) has never been performed. We investigated the diagnostic value of reactive hyperaemia (RH) and augmentation index (AI) as evaluated using PAT in men with ED of any origin. A total of 40 patients underwent diagnostic investigation for ED, including dynamic penile duplex ultrasound (PDU) and PAT device. Moreover, 30 patients without ED served as controls. According to PDU cutoff at 35 cm/sec, patients were divided into vascular (n = 30) and nonvascular (n = 10) ED aetiology. Moreover, controls with (n = 10) or without (n = 20) vascular risk factors (VRFs) were studied in a separate analysis. Average RH-PAT was not different in men with or without ED (P = 0.56) independently of VRFs. The AI was higher in men with ED compared with the controls (P < 0.0001) as well as when controlled for the presence or absence of VRFs (P < 0.0001). An inverse relationship between AI and PSV was also found (r2 = -0.72, P < 0.0001). In conclusion, an increased AI but not an impaired RH-PAT is present in men with vascular ED independently of VRFs and may represent an early detection of vascular impairment that may precede endothelial dysfunction in populations at low risk for developing vascular ED.