Pelvic floor muscle behavior during Valsalva leak point pressure measurement in males and females affected by stress urinary incontinence.
We evaluated pelvic floor muscle (PFM) behavior during Valsalva leak point pressure (VLPP) measurement in males and females affected by stress urinary incontinence and investigated whether VLPP results are influenced by PFM contraction. A total of 25 females and 14 males underwent surface electromyographic (EMG) recording of PFM activity while performing VLPP. We investigated 2 conditions, VLPP during spontaneous strain (test A), and with simultaneous relaxation of the pelvic floor (test B). We analyzed average EMG activity (microV) at rest and during VLPP in tests A and B, the increasing EMG activity during tests A and B (the difference between average EMG activity during tests A and B and at rest), and the mean duration (seconds) of EMG activity during tests A and B. We detected a significant increase in EMG activity during tests A and B as compared to activity at rest (p <0.0001). Increasing EMG activity during test B was significantly reduced in females (p <0.05) but not in males. During test A patients reporting urinary incontinence showed a significantly lower EMG activity than that of continent patients (p <0.05). A significant reduction in maximum abdominal pressure was detected in test B compared to test A, but there was no difference in VLPP values between tests A and B. PFM activity significantly increases during VLPP measurement. Eliminating muscular contraction of the pelvic floor does not significantly alter VLPP results.