BLOCKAGE OF THE POSITIVE FEEDBACK EFFECT OF OESTRADIOL DURING PROLONGED ADMINISTRATION OF CLOMIPHENE CITRATE TO NORMAL WOMEN

The effect of clomiphene citrate on the occurrence and timing of the endogenous LH surge in superovulated cycles is unclear. To study further this event, five normally ovulating women were treated with clomiphene citrate 100 mg per day in two different cycles, that is, for 5 days in one cycle (days 2 to 6, CC-5) and for 15 days in another cycle (days 2 to 16, CC-15). During the CC-5 cycle, the normal pattern of LH levels seen in spontaneous cycles was observed with an endogenous LH surge in all women followed by ovulation and normal luteal function. In contrast, during the CC-15 cycle, a continuous and progressive increase of basal LH levels was seen with no surge, resulting in follicular luteinization but no ovulation. The results suggest that in normal women treated with clomiphene the occurrence of an endogenous LH surge is dependent on a significant decrease in the circulatory concentration of clomiphene at mid-cycle.     

Carotid Sinus Hypersensitivity is Common in Patients Presenting with Hip Fracture and Unexplained Falls

Background: We tried to determine the prevalence of carotid sinus hypersensitivity (CSH) in patients with hip fractures with and without a clear history of an accidental fall.
Methods: We studied 51 patients hospitalized for a hip fracture and 51 matched controls from our outpatients department. All patients were subjected to a carotid sinus massage in the supine and upright position . Patients were categorized in accidental (Group A) and unexplained (Group B) fallers.
Results: Six of 33 (18.2%) patients in Group A and 12 of 18 (66.7%) patients in Group B ( P < 0.001) had a positive response to the carotid sinus massage. Nine controls (17.6%) also demonstrated CSH. Patients in Group B were older (A: 75.5 ± 8.5 years vs B: 80.1 ± 5.9 years, P = 0.029) and were more likely to have a history of unexplained falls or syncope in the past (A: 0% vs B: 66.7%, P < 0.0001) than individuals in group A. Vasodepressor/mixed forms accounted for the majority of CSH responses in Group B (75%). When compared with the control group, CSH was still more common in Group B (B: 66.7% vs control: 17.6%, P < 0.0001) but not in Group A (A: 18.2% vs control: 17.6%, P = 1.000).
Conclusions: The prevalence of CSH is increased in elderly patients with hip fractures, only in those who present with an unexplained fall and report a history of syncope or unexplained falls in the past. The vasodepressor/mixed forms account for the majority of CSH responses in the group of unexplained fallers.     

Placement of Intracoronary Stents Mounted on Over the Wire Balloon Catheters Without Using Long Guidewires

The aim of this study is to investigate the feasibility, effectiveness, and safety of placement of intracoronary stents mounted on over the wire balloon catheters without using long guidewires. Fifteen consecutive patients underwent GR II stent placement. Over the wire balloon catheters and short guidewires were used. The new method was successful in 14 of 15 cases. No complications were observed. This novel technique using a short (instead of long) guidewire to place intracoronary stents mounted on over the wire balloon catheters was successful, and more convenient. (J Interven Cardiol 2000; 13:27–30)     

The effects of early captopril treatment on left ventricular volumes and function in patients with and without depressed global ejection fraction after acute myocardial infarction

To determine the effects of captopril on left ventricular volumesand function in patients with and without depressed ventricularfunction following acute myocardial infarction (AMI) we studied78 patients with a first Q wave AMI and no clinical evidenceof heart failure. All patients underwent radionuclide ventriculography(RVG) on the 4th day after admission and were then randomlyassigned to receive conventional treatment alone (36 patients,control group) or with the addition of oral captopril, 25 mgthree times daily (42 patients, captopril group). RVG was repeatedone month after the baseline examination. After one month theleft ventricular ejection fraction (LVEF) significantly increasedin the captopril group (from 43.2±1.3 to 50.9±1.6%,P<0.001) and remained relatively unchanged in the controlgroup (from 47±1.3 to 49.2±1.7%, P=ns). In thecaptopril group the subgroup of patients with a baseline LVEF<45% demonstrated a significant decrease in end-systolicvolume index (ESVI) (from 53.3 ±3.2 to 42.4±2.8ml.m^–2,P<0.002) and a highly significant improvement in LVEF (from36.3±1.3 to 49.6±1.8%, P<0.00005). In the controlgroup, LVEF also increased in those in whom it was <45% (from38±1.4 to 42±2.4%, P<0.01), but the increasewas less than that in the captopril group (P<0.01), mainlydue to an increase in end-diastolic volume index (EDVI) (from78.2±4.6 to 84.6±12.3 ml.m^–2, P=ns). Inboth the captopril and control subgroups of patients with abaseline LVEF 45% there was no significant change in LVEF (from50.1±0.8 to 52.1±2.6% and 53.4±1.5 to 54.2±2.1%respectively), but there was a trend for both left ventricularvolumes to increase (EDVI: from 81.4±4.7 to 91.1±9.9ml.m^–2and 76±5.7 to 90.3±9.2 ml.m^–2; ESVI: from40.6±2.6 to 45.2 ±3.4 ml.m^–2 and 32.1±2.6to 40.1 ±3.8 ml.m^–2 respectively, all P=ns). In conclusion, our study confirmed the beneficial effect ofcaptopril on left ventricular size and function in patientswith depressed global LVEF after AMI, but there was no evidenceof a similar effect in patients with preserved global LVEF,at least during the first month of treatment.     

The effect of the antiprogestin mifepristone (RU 486) on maturation and in-vitro fertilization of human oocytes

Summary. The effect of RU 486 (mifepristone), a potent antiprogestin, on the in-vitro fertilization of human oocytes was investigated. In 40 normal volunteer women requesting laparoscopic sterilization, follicle aspiration for oocyte recovery was attempted 34 h after the injection of 5000 i.u. human chorionic gonadotrophin (hCG). Twenty women were allocated to receive 100 mg RU 486 orally 1 h before the hCG injection, the remaining 20 women acted as controls. There was no significant difference in the cleavage rate of the ooctyes after fertilization in vitro between the two groups (56% and 66% respectively). Also, the morphological characteristics of the cleaving oocytes and the concentrations of oestradiol, progesterone and androstenedione in the follicular fluid of the leading follicle did not differ significantly between the two groups. Since RU 486 was detected in substantial amounts in the follicular fluid specimens, these results suggest that progesterone is not critical for the final stages of human oocyte maturation.     

A comparison of fixed regimens for obtaining human cleaving oocytes for research purposes

Summary. A fixed schedule for ovarian stimulation and follicular aspiration, previously used in our department for research purposes, was modified in an attempt to increase the recovery and cleavage rates of the oocytes. Three different clomiphene regimens were used to stimulate the ovaries of normal volunteer women requesting laparoscopic sterilization (50 mg and 150 mg daily for 5 days, and 50 mg daily for 10 days). Oocytes were recovered from 83% of the aspirated follicles, i.e. 1·6 oocytes/patient: 65% of the oocytes cleaved after in-vitro fertilization and, on average, 1·0 cleaving egg was obtained per patient. There were no differences in the recovery and cleavage rates between the three clomiphene regimens. It is concluded that a sufficient number of cleaving embryos for research purposes can be generated with the present fixed regimen, which offers little inconvenience to the volunteers as the day of egg recovery can be predicted some time in advance.     

First Lessons from Radiofrequency Catheter Ablation in Patients with Ventricular Tachycardia

Fourteen patients (12 men, 2 women; 61 ± 9 years) with ventricular tachycardia and underlying heart disease underwent an attempt at radiofrequency energy catheter ablation. Twelve patients had coronary disease and two patients had dilated cardiomyopathy. Two patients had two clinical tachycardias, the ejection fraction was 38%± 11%. All tachycardias were inducible and hemodynamically well tolerated (cycle length = 357 ± 56 msec). Ablation was initially successful in nine patients (no tachycardia inducible after ablation and before discharge). Two patients had recurrences (in-hospital and 4 months) and one patient had a tachycardia of a different morphology, which was also successfully ablated. Ablation was overall successful in seven patients and unsuccessful in seven patients (including all patients with cardiomyopaihy). Mid-diastolic potentials were observed in all the patients in whom ablation was successful but not observed in four of seven unsuccessful patients. The successful patients remain free of recurrences at 9 ± 8 months follow-up. Conclusions: (1) in ventricular tachycardia following an old infarction radiofrequency energy ablation is possible with a high success rate if a critical component of the tachycardia circuit can be localized. Localizing isolated mid-diastolic potentials and ensuring these potentials are part of the reentrant circuit with concealed entrainment can help to enhance the results. (2) A negative predischarge electrophysiological study may be predictive of success.