The quality of penile erectile function was categorized

Subjective Sexual Function

The subjects provided sexual histories to a trained interviewer regarding the following: (1) frequency of sexual intercourse, (2) level of interest in sexual activity, (3) observation of spontaneous morning erections, and (4) quality of penile erections (duration and firmness). Changes in these parameters were recorded as percentage of the level of function at the time of the study vs the level of function just prior to the onset of severe exertional dyspnea (premoibid level). The observation of morning erections was recorded as same, decreased, or absent. The quality of penile erectile function was categorized as follows:

0. No change in firmness or duration of erection from die premorbid state.

1. Slight or moderate decrease in firmness or duration but no difficulty completing coitus.

2. Firm to semifirm erections capable of intromission but with as much as 75 percent reduction in duration. Subject is usually able to complete coitus.

3. Firm to semifirm erection that detumesces after intromission, frequently before climax.

4. Semifirm erection, much shortened in duration, usually not able to achieve intromission, occasional short-duration, firm erections.

5. Usually flaccid penis with occasional short-duration, semifirm erections or no erections at all.

Objective Erectile Function

Mercury-filled Silastic strain gauges placed at the tip and base of the penis and connected to a tumescence monitor (Event Systems) were used during three nights of polygraphic monitoring to evaluate erectile function objectively. Sleep stages were recorded by EEC and scored according to criteria of Rechtschaffen and Kales. Tumescence studies were scored according to criteria of Karacan et al and Fisher et al. Full erections required a circumferential change exceeding 16 mm or 80 percent of a maximal erection measured at the tip. The duration of full erections was reported as the time from initial deflection to the time of return to baseline (Fig 1). If the subject had no full nocturnal erections or an average of less than one full erection lasting at least five minutes per night of monitoring he was considered to have organogenic impotence.