Biomedical subjects

Dimitrios Hatzichristou

Publications and source records attributed to Dimitrios Hatzichristou.

5 recordsLinked to original sources

PubMed2003

Effects of sildenafil on cardiopulmonary responses during stress.

PURPOSE: To investigate possible effects of sildenafil on the cardiopulmonary responses during sexual intercourse we evaluated cardiopulmonary responses during exercise in a group of impotent patients. MATERIALS AND METHODS: The study sample included patients with erectile dysfunction who underwent a cardiopulmonary exercise test before and after the administration of 100 mg. sildenafil citrate. Cardiopulmonary exercise test parameters at rest, at the anaerobic threshold, at peak exercise and at 1-minute recovery were recorded, including systolic and diastolic blood pressure, the heart rate, O2 consumption, CO2 production, ventilation and the respiratory rate. Furthermore, O2 consumption per kg. body weight, the ventilatory equivalent for O2 consumption (ventilation/O2 consumption) and CO2 production (ventilation/CO2 production), the respiratory quotient, metabolic equivalents metabolic equivalents, oxygen pulse (O2 consumption/heart rate) and the change in O2 consumption/change in heart rate were calculated. RESULTS: In 2 of the 43 patients enrolled in the study myocardial ischemia and high blood pressure were detected at rest in 2, respectively, who were excluded from analysis. In the remaining 41 patients with a mean age +/- SD of 52.3 +/- 8.6 years a statistically significant decrease in systolic and diastolic blood pressure was noted after sildenafil use at all stages tested (p <0.002 to 0.001). The heart rate mildly increased after sildenafil use at rest and at peak exercise (p = 0.018). The O2 pulse decreased at the anaerobic threshold (p = 0.003), peak exercise (p = 0.001) and recovery (p = 0.047). In the 11 patients with a mean age of 40.8 +/- 10.12 years who had psychogenic erectile dysfunction the only 2 parameters affected were an increased heart rate and decreased systolic blood pressure at rest, while O2 consumption/heart rate decreased at the anaerobic threshold. In the 18 patients with a mean age of 61.1 +/- 8.9 years who had organic erectile dysfunction and an unremarkable medical history a decrease was noted in systolic and diastolic blood pressure at rest and at peak exercise, and diastolic blood pressure also at recovery, while the heart rate increased at recovery. In the 12 patients with a mean age of 60.16 +/- 9.12 years who had treated cardiovascular disease systolic and diastolic blood pressure decreased at all states and O2 consumption/heart rate at the anaerobic threshold and at peak exercise, while increased values were noted for the respiratory rate at the anaerobic threshold and ventilation/CO2 production at recovery. CONCLUSIONS: Hemodynamic changes after sildenafil administration should be considered minimal in concert with patient health status. Younger patients without signs of systemic atherosclerosis compensate the vasodilatory effect of sildenafil during exercise, while in older patients with vasculogenic erectile dysfunction moderate changes may be noted regardless of cardiovascular disease in the medical history.

Adult↗

PubMed2002

Management strategy for arterial priapism: therapeutic dilemmas.

PURPOSE: We present 7 cases of arterial high flow priapism and propose management algorithms for the condition. MATERIALS AND METHODS: We studied 2 children and 5 adults with posttraumatic arterial priapism. Blood gas analysis and color Doppler ultrasonography of the corpora cavernosa confirmed the diagnosis in 4 adults, while 1 patient had already undergone cavernous artery ligation in elsewhere. In the children perineal compression resulted in detumescence, a sign that is proposed to be indicative of the diagnosis of arterial priapism (piesis sign) complementing physical examination. Mechanical compressive force was applied to the perineum of 1 boy, while the other received a watchful waiting program. All adults participated in an observation regimen except 1, who decided to undergo immediate embolization of the internal pudendal artery. RESULTS: Perineal compression led to the resolution of priapism in 1 child, while spontaneous resolution was noted in the other. An adult noticed spontaneous penile detumescence 3 to 4 months after trauma, which was attributable to site specific venous leakage and decreased, inflow in the contralateral cavernous artery. The patient underwent venous surgery and is on an intracavernous injection regimen. Successful embolization of the internal pudendal artery was performed immediately in 1 man and in the other 4 months after trauma due to social inconvenience. Adult patient 3 is still on the watchful waiting protocol (42 months), while the one who underwent cavernous artery ligation is receiving treatment for erectile dysfunction. CONCLUSIONS: Absent of long-term damaging effects of arterial priapism on erectile tissue combined with the possibility of spontaneous resolution or progressive concomitant hemodynamic abnormalities associated with blunt perineal trauma are suggestive of the introduction of an observation period in the management algorithm of high flow priapism. Such a period may help avoid unnecessary intervention and determine the impact of priapism on patient personal life. Perineal compression may be also added as part of the physical examination as a sign specifically indicative of arterial priapism.

Adult↗

PubMed2002

Achieving treatment optimization with sildenafil citrate (Viagra) in patients with erectile dysfunction.

Since its approval in 1998, sildenafil citrate (Viagra) has been shown to be efficacious in >100 clinical trials involving >8000 men with erectile dysfunction (ED). In clinical practice, however, many men do not continue long-term use of sildenafil for a variety of reasons; thus, 6 different aspects of optimizing treatment with sildenafil are described here. (1) Intercourse success rates, considered a reflection of real-world effectiveness, were assessed in 1276 patients with ED. Results indicated that the cumulative probability of achieving intercourse success with sildenafil increased with the number of attempts, reaching a plateau after approximately 8 attempts. (2) A comprehensive disease management approach that included a medical history, physical examination, educational material about ED, modifications of risk factors/lifestyle changes, and counseling resulted in successful intercourse in 74% of 111 patients taking sildenafil. (3) A survey conducted among primary care physicians revealed that almost 50% did not routinely question their patients about ED symptoms, although it is known that most patients would prefer their physician to take the initiative. (4) Overall, 55% of 137 men who were previously not successful with sildenafil became successful after reeducation and counseling, which included information on patient and partner expectations, how to properly take the drug, titration to maximum dose, and a minimum trial of 8 attempts for efficacy assessment. (5) Many men with ED have underlying comorbidities or take multiple medications that are risk factors for ED. Controlling these risk factors in 521 men from a multispecialty clinic led to an overall intercourse success rate of 82%; patients with multiple risk factors were less likely to have intercourse success than men with only 1 risk factor. (6) Finally, treatment satisfaction is a pivotal factor in maintaining long-term ED therapy. In an open-label trial, 82% of 443 subjects reported treatment satisfaction with sildenafil. In summary, these findings highlight how important it is for physicians to take a more comprehensive, proactive approach when treating men with ED, including control of risk factors, instructions on how to properly take the drug, partner involvement, and follow-up visits. Using these recommended measures, most men with ED, including those whose treatment was previously unsuccessful, can be treated successfully with sildenafil.

Coitus↗

PubMed2002

Guidelines on erectile dysfunction.

The introduction of new oral therapies has completely changed the diagnostic and therapeutic approach to erectile dysfunction. A panel of experts in this field have developed guidelines for clinical evaluation and treatment based on the review of available scientific information.

Adult↗

PubMed2002

Diagnostic steps in the evaluation of patients with erectile dysfunction.

PURPOSE: The necessity for a thorough diagnostic evaluation for erectile dysfunction has been questioned after the availability of effective oral therapies. We determined the impact of the different diagnostic steps on the management strategy for erectile dysfunction. MATERIALS AND METHODS: The study included all patients who presented at an andrology outpatient clinic during a 4-year period. Baseline evaluation included medical and sexual history, blood tests, physical examination and intracavernous injection test. Patients with normal initial screening were evaluated with specific diagnostic procedures. The results were analyzed to identify the diagnostic potential of each screening step separately. RESULTS: Overall 1,644 patients presented at the clinic during the study period, of whom 368 (22.4%) were excluded from study due to severe psychiatric (5.2%) or cardiovascular (2.7%) disease, or to a history of erectile dysfunction less than 3 months in duration (14.5%). In the remaining 1,276 patients with a mean age plus or minus standard deviation of 56 +/- 14 years, and a mean duration of erectile dysfunction of 4.9 +/- 3.4 years medical history revealed erectile dysfunction associated medical conditions in 57%, blood tests identified previously undiagnosed medical conditions in 6.2%, and physical examination and the intracavernous injection test were diagnostic in 13.9% and 2.6%, respectively. Initial screening was negative in 259 cases (20.3%), in which specific diagnostic procedures identified an underlying vascular pathology in 165 (12.9%) and unfavorable penile geometry in 16 (1.3%). The remaining 78 men (6.1%) had no evidence of organic disease. CONCLUSIONS: Baseline diagnostic evaluation for erectile dysfunction can identify the underlying pathological condition or erectile dysfunction associated risk factors in 80% of patients. Such screening may diagnose reversible causes of erectile dysfunction and also unmask medical conditions that manifest with erectile dysfunction as the first symptom. Specific diagnostic procedures may be limited in patients with primary erectile dysfunction or those without risk factors. Such clinical data support previously published guidelines for erectile dysfunction management.

Adult↗