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S Rex

Publications and source records attributed to S Rex.

At least 19 recordsLinked to original sources
PubMed2006

Intra- and extravascular volume status in patients undergoing mitral valve replacement: crystalloid vs. colloid priming of cardiopulmonary bypass.

BACKGROUND AND OBJECTIVE: Cardiopulmonary bypass is associated with changes of intra- and extravascular volume status often resulting in cardiopulmonary dysfunction. The purpose of this prospective double-blind study was to evaluate the influence of different priming solutions of the extracorporeal circuit on intra- and extravascular volume status and haemodynamics in patients undergoing elective mitral valve replacement. METHODS: Twenty-two patients with mitral valve insufficiency were randomly allocated into two equal groups. In Group 1 cardiopulmonary bypass was primed with a nearly isooncotic solution consisting of 4% albumin. The second group received a pure crystalloid priming solution. The thermo-dye indicator dilution technique was used for the assessment of cardiac output, central and pulmonary blood volume, right ventricular end-diastolic volume and total blood volume. RESULTS: Patients in the crystalloid group showed increased intraoperative fluid requirements. Significantly more fluid was accumulated in the extravascular space whereas total blood volume was decreased after surgery. Stroke volume index (SVI) was significantly decreased in the immediate postoperative period when compared to baseline. As indicated by the increase in extravascular fluid content after surgery, both colloid and crystalloid priming volumes were transferred to the extravascular space. CONCLUSION: The use of colloid priming solutions in patients with mitral valve insufficiency leads to less fluid requirements and significantly reduced fluid shift in the interstitium. However, these changes are not associated with changes in haemodynamic parameters or short term outcome.

Adrenergic beta-Agonists↗
PubMed2005

Hepatitis A outbreak among MSM linked to casual sex and gay saunas in Copenhagen, Denmark.

During an outbreak of hepatitis A predominantly among men who have sex with men (MSM) in Copenhagen, Denmark, in 2004, we did a case-control study to determine risk factors for infection. A case was an MSM >17 years, living in Copenhagen, with IgM positive hepatitis A infection diagnosed between June and August 2004, and without a household contact with a hepatitis A case before onset of illness. Controls were selected at the Copenhagen Pride Festival. The study included 18 cases and 64 controls. Sixteen of 18 cases and 36/63 controls had sex with casual partners (ORMH 5.6, 95% CI 1.2-26.9). Eleven of 18 cases and 14/62 controls had sex in gay saunas (ORMH 4.2, 95% CI 1.5-11.5). Sex at private homes appeared to be protective (ORMH 0.2, 95% CI 0.1-0.7). Casual sex including sex in gay saunas was an important risk factor for the spread of HAV among MSM in Copenhagen. The results are in accordance with findings in other European outbreaks. As the general immunity to hepatitis A decreases and the outbreak potential increases, we recommend health education and hepatitis A vaccination to all MSM not living in monogamous relationships, especially if they visit gay saunas or other places with frequent partner change. To stop spread of hepatitis A among MSM in Europe, a European consensus on prevention and control measures may be required.

Adult↗
PubMed2004

Prediction of fluid responsiveness in patients during cardiac surgery.

BACKGROUND: Left ventricular stroke volume variation (SVV) has been shown to be a predictor of fluid responsiveness in various subsets of patients. However, the accuracy and reliability of SVV are unproven in patients ventilated with low tidal volumes. METHODS: Fourteen patients were studied immediately after coronary artery bypass grafting (CABG). All patients were mechanically ventilated in pressure-controlled mode [tidal volume 7.5 (1.2) ml kg(-1)]. In addition to standard haemodynamic monitoring, SVV was assessed by arterial pulse contour analysis. Left ventricular end-diastolic area index (LVEDAI) was determined by transoesophageal echocardiography. A transpulmonary thermodilution technique was used for measurement of cardiac index (CI), stroke volume index (SVI) and intrathoracic blood volume index (ITBI). All variables were assessed before and after a volume shift induced by tilting the patients from the anti-Trendelenburg (30 degrees head up) to the Trendelenburg position (30 degrees head down). RESULTS: After the change in the Trendelenburg position, SVV decreased significantly, while CI, SVI, ITBI, LVEDAI, central venous pressure (CVP) and pulmonary artery occlusion pressure (PAOP) increased significantly. Changes in SVI were significantly correlated to changes in SVV (r=0.70; P<0.0001) and to changes in LVEDAI, ITBI, CVP and PAOP. Only prechallenge values of SVV were predictive of changes in SVI after change from the anti-Trendelenburg to the Trendelenburg position. CONCLUSIONS: In patients after CABG surgery who were ventilated with low tidal volumes, SVV enabled prediction of fluid responsiveness and assessment of the haemodynamic effects of volume loading.

Aged↗
PubMed2004

Placental protein 14 concentrations in circulation related to hormonal parameters and reproductive outcome in women undergoing IVF/ICSI.

Serum concentrations of placental protein 14 (PP14), steroids and gonadotrophins were related to the outcome of IVF/intracytoplasmic sperm injection in 195 normogonadotrophic women subjected to the long protocol gonadotrophin-releasing hormone agonist (GnRHa; buserelin) pituitary down-regulation protocol and gonadotrophin stimulation (HMG or rFSH). Pituitary down-regulation was initiated on cycle day 21 and the patients were randomized to either intranasal or s.c. administration of buserelin. After 14 days of down-regulation, the patients were randomized on stimulation day 1 (S1) to ovarian stimulation with 225 IU per day of either human menopausal gonadotrophin (HMG) or recombinant FSH (rFSH) for a fixed period of 7 days. The daily gonadotrophin dose was adjusted on the following day according to ovarian response. Patient's blood was sampled for PP14 and hormone analysis on cycle days 21, S1, S8 and on the day of oocyte retrieval. Mean concentrations of PP14 on day 21 of the cycle were significantly lower in conception than in non-conception cycles, whereas progesterone and oestradiol were similar in conception and non-conception cycles. PP14 concentrations on the first day of stimulation and at oocyte retrieval were significantly higher in conception than in non-conception cycles, whereas concentrations after 8 days of stimulation were similar. Neither mode of GnRHa administration nor type of gonadotrophin significantly influenced PP14 concentrations throughout ovarian stimulation. Circulating PP14 is thus an important physiological signal of the fertility status of the individual in the cycle antecedent to and during ovarian stimulation. Measuring mid-luteal serum PP14 may offer a clinical test helping to decide if infertility treatment should be initiated in the subsequent cycle.

Adult↗
PubMed2004

Concentrations of gonadotrophins and steroids in pre-ovulatory follicular fluid and serum in relation to stimulation protocol and outcome of assisted reproduction treatment.

In this prospective, randomized study, concentrations of gonadotrophins and steroids in pre-ovulatory follicular fluid (FF) and serum were related to type of stimulation protocol as well as to the outcome of assisted reproduction in 280 women subjected to the long protocol gonadotrophin-releasing hormone (GnRH) agonist pituitary down-regulation and ovarian stimulation with either human menopausal gonadotrophin (HMG) or recombinant FSH. In the women treated with HMG, concentrations of LH, FSH, oestradiol and androstenedione in FF were significantly higher, and those of human chorionic gonadotrophin (HCG) and progesterone significantly lower, than in the women treated with recombinant FSH (rFSH). More women became pregnant and delivered in the HMG than in the rFSH group. These differences, however, were not statistically significant. Concentrations of FSH in serum and of FSH and LH in FF were significantly higher in conception than in non-conception cycles, whereas all other hormone concentrations in FF and serum were similar. The present study demonstrates that the pre-ovulatory follicular fluid hormone profile is significantly influenced by the gonadotrophin preparation used for ovarian stimulation, and suggests that ovarian stimulation with HMG results in an intra-follicular hormone profile more similar to that characterizing conception cycles than stimulation with rFSH. However, as the present data represent means of FF hormone profiles, they do not allow the conclusion of a direct correlation between the intra-follicular concentration of a certain hormone and the ability of the corresponding embryo to implant and establish an ongoing pregnancy.

Buserelin↗
PubMed2001

Human menopausal gonadotropin versus recombinant follicle-stimulating hormone in normogonadotropic women down-regulated with a gonadotropin-releasing hormone agonist who were undergoing in vitro fertilization and intracytoplasmic sperm injection: a prospective randomized study.

OBJECTIVE: To evaluate clinical and endocrinological effects of intranasal (IN) vs. subcutaneous (SC) GnRH-a for pituitary down-regulation combined with hMG vs. rFSH. DESIGN: Prospective, randomized study. SETTING: University hospital, IVF unit. PATIENT(S): Three hundred seventy-nine normogonadotropic women eligible for IVF or ICSI. INTERVENTION(S): Randomization to intranasal (IN) or SC GnRH-a and to hMG or rFSH. MAIN OUTCOME MEASURE(S): Oocytes retrieved, embryos developed, clinical pregnancy, and delivery rates. Serum hormone concentrations on stimulation days 1 (S1) and 8 (S8), and oocyte pick-up (OPU) day. RESULT(S): After randomization, four groups were formed: IN/hMG (n = 100), IN/FSH (n = 98), SC/hMG (n = 89), and SC/FSH (n = 92). Mean number of oocytes retrieved and of transferable and transferred embryos were similar in the four groups. Clinical pregnancy rate per started cycle was significantly higher in the IN/HMG group than in the SC/FSH group (P<.05) and was intermediate in the two remaining groups. Se-LH on S8 in the two SC groups was significantly lower than in the two IN groups. Se-E2 on S8 in the SC/FSH group was significantly lower than in the other three groups. CONCLUSION(S): The clinical and endocrinological outcome in IVF and ICSI-treated normogonadotropic women is significantly influenced by mode of down-regulation as well as gonadotropin formulation.

Administration, Intranasal↗
PubMed2001

Intrauterine insemination with donor semen. An evaluation of prognostic factors based on a review of 1131 cycles.

OBJECTIVE: To identify prognostic factors influencing the outcome of infertility treatment using intrauterine insemination with donor semen (IUI-D). DESIGN: Retrospective study of all patients undergoing IUI-D between August 1st, 1990 and July 31st, 1998. SETTING: University-affiliated infertility clinic. PATIENTS: Three hundred and five couples undergoing 1131 IUI-D treatment cycles. MAIN OUTCOME MEASURES: Type of hormonal treatment, number of follicles, length of follicular phase, endometrial pattern, female age, infertility diagnosis and semen quality related to clinical pregnancy rate, cumulative birth rate and multiple gestations. RESULTS: Throughout the nine year period the overall clinical pregnancy rate per cycle was 22.3%, with an increase from 12.9% in 1990 to 34.6% in 1998. The multiple birth rate was 20.6%. The birth rate per couple was 61.1% after a mean of 3.2 treatment cycles. The pregnancy rate was highest in the first treatment cycle and the cumulative birth rate rose only slightly after the sixth treatment cycle. The following parameters were positively and significantly correlated to a successful outcome of IUI-D: i) the first treatment cycle - compared to the following up to six treatment cycles; ii) number of mature follicles - more than one - at the time of insemination, however, with an unacceptable high rate of multiple pregnancies when more than 3 mature follicles were present; iii) time of insemination after the 12th day in the cycle; iv) insemination after ovulation has occurred and; v) female age under 30 years. CONCLUSIONS: IUI-D is a simple and inexpensive treatment giving acceptable pregnancy rates for up to six treatment cycles if at least 2 mature follicles have developed at the time of insemination, which implies that hormonal ovarian stimulation and induction of ovulation is used, and ovulation has occurred at the time of insemination, which ought to take place after cycle day (cd) 12 with at least two million motile spermatozoa.

Adult↗
PubMed2001

Homologous intrauterine insemination. An evaluation of prognostic factors based on a review of 2473 cycles.

OBJECTIVE: To identify prognostic factors influencing the outcome of infertility treatment using homologous intrauterine inseminations (IUI-H). DESIGN: Retrospective study of all patients undergoing IUI-H at the Fertility Clinic, Odense University Hospital from August 1st, 1990 to July 31st, 1998. SETTING: University-affiliated infertility clinic. PATIENTS: Eight hundred and ninety-three couples undergoing 2473 IUI-H treatment cycles. MAIN OUTCOME MEASURES: Infertility diagnosis, female age, number of follicles, type of hormonal treatment, length of follicular phase, endometrial pattern, and semen quality related to clinical pregnancy rate, cumulative birth rate and multiple gestations. RESULTS: Throughout the nine year period the overall clinical pregnancy rate per IUI-H cycle was 11.9% with a significant increase from 8.7% in 1990 to 14.8% in 1998. The multiple birth rate was 18.1%. The birth rate per couple was 27.2% after a mean of 2.8 treatment cycles. The pregnancy rate was highest in the first treatment cycle and the cumulative birth rate rose only slightly after the fourth treatment cycle. Of the main outcome measures the following were positively and significantly related to a successful outcome of IUI: i) The first treatment cycle - compared to the following up to six treatment cycles; ii) number of mature follicles up to five - at the time of insemination, however, with an unacceptable high rate of multiple pregnancies with more than 4 mature follicles; iii) use of CC/hMG-FSH as compared to CC only for ovarian stimulation; iv) number of motile sperms inseminated exceeding 5 million; v) time of insemination between the 13th and the 16th day in the cycle and vi) anovulatory or idiopathic infertility. CONCLUSIONS: IUI-H is a simple and inexpensive treatment giving acceptable pregnancy rates for up to four treatment cycles providing that at least 3 to 4 mature follicles have developed at the time of insemination, which implies that hormonal ovarian stimulation and induction of ovulation is used, that insemination occurs between cycle day 13 and 16 and that at least 5 million motile sperms are available for insemination. Our results indicate that in the presence of tubal pathology or less than 5 million motile sperms, the couples should be referred directly to IVF-treatment.

Adult↗
PubMed2001

No incremental benefit of multisite atrial pacing compared with right atrial pacing in patients with drug refractory paroxysmal atrial fibrillation.

OBJECTIVE: To evaluate the incremental antifibrillatory effect of multisite atrial pacing compared with right atrial pacing in patients with drug refractory paroxysmal atrial fibrillation paced for arrhythmia prevention alone. METHODS: In 20 of these patients (mean (SD) age 64 (8) years; 14 female, six male), a single blinded randomised crossover study was performed to investigate the incremental benefit of one month of multisite atrial pacing compared with one month of right atrial pacing. Outcomes included the number of episodes of paroxysmal atrial fibrillation, their total duration obtained from pacemaker Holter memory, and quality of life using a cardiac specific questionnaire (the modified Karolinska questionnaire). RESULTS: Comparing right atrial with multisite atrial pacing, there was no significant change in either the number of paroxysmal atrial fibrillation episodes (mean (SD): right atrial pacing 77 (98) episodes v multisite pacing 52 (78) episodes, NS) or their total duration (right atrial, 4.8 (5.4) days v multisite, 6.3 (9.8) days, NS). Quality of life scores compared with baseline status were equally improved by either pacing strategy (mean percentage improvement: right atrial, 38%, p = 0.003; multisite, 44%, p = 0.003). There was no significant difference in life scores comparing the two pacing modes. CONCLUSIONS: Multisite atrial pacing has no incremental antiarrhythmic effect compared with right atrial pacing in patients paced for drug refractory paroxysmal atrial fibrillation. Quality of life is equally improved with either pacing strategy, with no differences between them.

Aged↗
PubMed2001

Importance of rate control or rate regulation for improving exercise capacity and quality of life in patients with permanent atrial fibrillation and normal left ventricular function: a randomised controlled study.

OBJECTIVE: To determine the importance of rhythm regulation or rate control in patients with permanent atrial fibrillation (AF) and normal left ventricular function. PATIENTS AND INTERVENTIONS: Thirty six patients with a mixed fast and slow ventricular response rate to their AF were randomised to either His bundle ablation (HBA) and VVIR pacemaker (HBA group) or VVI pacemaker and atrioventricular modifying drugs (Med group). Outcomes assessed at one, three, six, and 12 months included exercise duration and quality of life. RESULTS: Exercise duration significantly improved from baseline in both groups. There was no difference in outcome between the groups (Med +40% v HBA +20%, p = NS). The heart rate profile on exercise was similarly slowed in both groups compared to baseline. Quality of life significantly improved in both treatment arms for the modified Karolinska questionnaire (KQ) (Med +50% v HBA +50%, p = NS) and the Nottingham health profile (NHP) (Med +40% v HBA +20%, p = NS). However, for the individual symptom scores of each questionnaire more were improved in the Med group (KQ-Med 6 improved v HBA 4, NHP-Med 3 v HBA 1). Left ventricular function was equally preserved by both treatments during follow up. CONCLUSION: In these patients control of ventricular response rate with either HBA + VVIR pacemaker or atrioventricular modifying drugs + VVI pacemaker will lead to a significant improvement in exercise duration and quality of life. Rhythm regulation by HBA did not confer additional benefit, suggesting rate control alone is necessary for the successful symptomatic treatment of these patients in permanent AF.

Aged↗
PubMed2000

Randomized controlled study investigating the effect of biatrial pacing in prevention of atrial fibrillation after coronary artery bypass grafting.

BACKGROUND: Atrial fibrillation (AF) is a common problem after CABG. Prevention with prophylactic drug therapy has had limited success, therefore alternative approaches are required. This study investigated the role of biatrial pacing compared with no pacing on AF incidence after isolated first-time CABG. METHODS AND RESULTS: During surgery, temporary pacing leads were placed in the lateral wall of the right atrium and at the roof of the left atrium in Bachmann's bundle to allow bipolar pacing and sensing at each site. After surgery, all patients were connected to an external pacemaker (Chorum ELA) that also acted as a Holter monitor. Patients were consecutively randomized to either 4 days of biatrial pacing at a base rate of 80 bpm or to no pacing (control group, base rate 30 bpm). End points included an episode of AF lasting >1 hour on pacemaker Holter, clinically detected AF, intensive care unit (ICU) and hospital stay, and postoperative complications. One hundred thirty patients were randomized. Biatrial pacing significantly reduced both monitored (13.8% versus 38.5%, P:=0.001) and clinical (10.8% versus 33.8%, P:=0.002) episodes of AF. Median ICU (19 versus 24 hours, P:=NS) and mean hospital stay (7.7+/-6.9 versus 9.7+/-10, P:=NS) did not significantly change. The number of postoperative complications was lower in the biatrial group (13 versus 35, P:=0. 001). CONCLUSIONS: Biatrial pacing after CABG significantly decreases the incidence of AF. This is associated with reduced postoperative complications and a trend toward reduced ICU and hospital stay.

Aged↗
PubMed2000

Ablate and pace for drug refractory paroxysmal atrial fibrillation. Is ablation necessary?

BACKGROUND: Atrio-ventricular junctional ablation with pacemaker insertion has been shown to improve quality of life in patients with drug refractory paroxysmal atrial fibrillation. It is unknown whether this improvement is secondary to the ablation procedure or to the pacemaker mode utilised. To investigate this we reviewed our experience of implanting a dual chamber rate responsive pacemaker with mode switching (DDDR/MS) alone on quality of life in this patient group. METHODS AND RESULTS: Over a 1-year period, 19 patients (mean age 62+/-9 years, 13 female) with drug refractory paroxysmal atrial fibrillation (mean duration of symptoms 8.7+/-7 years, failed 3.1+/-0.9 anti-arrhythmic drugs, amiodarone in 15) were recruited. Quality of life was assessed at baseline and after 1 month using a cardiac specific questionnaire, the modified Karolinska questionnaire. The mean score for all patients significantly improved by 39% at follow up (baseline 59+/-24, 1 month 36+/-24, P=0.001). Individually 15 patients (79%) had an improvement in their score, whilst for 13 patients (68%) their symptoms were sufficiently improved after pacing that ablation was not required. The benefit was maintained to a mean follow up of 12+/-5 months (score 31+/-20, P<0.001). Six patients remained symptomatic after pacing and requested further treatment. Benefit was unrelated to symptoms at baseline or the number and total duration of paroxysmal atrial fibrillation episodes recorded on pacemaker Holter. CONCLUSIONS: Patients with drug refractory paroxysmal atrial fibrillation, DDDR/MS pacing alone can improve quality of life without concurrent atrio-ventricular junctional ablation in a significant proportion of patients.

Aged↗
PubMed2000

A Pro --> Ala substitution in melittin affects self-association, membrane binding and pore-formation kinetics due to changes in structural and electrostatic properties

Melittin, the main component of bee venom of Apis mellifera, contains a proline at position 14, which is highly conserved in related peptides of various bee venoms. To investigate the structural and functional role of Pro14 a melittin analogue was studied where proline is substituted by an alanine residue (P14A). The investigations were focussed on: (i) the secondary structure in aqueous solution and membranes; (ii) the self-association in solution; (iii) the binding to POPC membranes; and (iv) the P14A-induced leakage and pore formation in membrane vesicles. Circular dichroism and gel filtration experiments showed that P14A exists at concentrations < 12 microM in monomeric form with an alpha-helicity of 28 +/- 7%. A further increase in peptide concentration leads to the formation of large aggregates consisting of 9 +/- 1 monomers. While binding studies with POPC vesicles revealed for P14A a stronger binding affinity towards membranes than for melittin, the peptide-induced leakage of fluorescent markers from vesicles was less efficient for P14A than for melittin. Furthermore, an unexpected efflux behaviour at high values of bound P14A was observed which indicated that the pore formation kinetics for P14A is more complex than it was reported for melittin. The different features of P14A in aggregation, binding and efflux compared to melittin are mainly ascribable directly to structural changes caused by the proline --> alanine substitution. Furthermore, the results indicate an improved screening of the positively charged residues of P14A by counterions which contributes additionally to the observed differences in peptide activities. It is suggested that the presence of proline in melittin is not only of structural importance but also influences indirectly the electrostatic properties of the native peptide.

Journal Article↗
PubMed2000

Does atrial overdrive pacing prevent paroxysmal atrial fibrillation in paced patients?

The role of atrial overdrive pacing for the suppression of paroxysmal atrial fibrillation remains unclear. To investigate this we have performed a randomised study evaluating the role of an increased atrial base rate in suppressing this arrhythmia in patients implanted with a permanent pacemaker (Chorum ELA) for sick sinus syndrome with previous documented paroxysmal atrial fibrillation. Twenty-seven patients (mean age, 69; 15 female) were randomised to two 3-month single-blinded crossover periods of DDDR pacing. The pacemaker was set with a base rate of 60 bpm (normal) during one period and at 10 bpm (overdrive) above the average heart rate during the other, mean (S.D.) 75+/-7 beats/min (range, 70-96). The fallback algorithm of the pacemaker was activated to record the number and duration of paroxysmal atrial fibrillation episodes. During the overdrive period there was a significant increase in the total duration of atrial pacing (normal 60+/-26% vs. overdrive 72+/-28%, P<0.001). However there was no significant difference in the number of paroxysmal atrial fibrillation episodes (normal 43+/-109 vs. overdrive 43+/-106, P=ns), or their total duration (normal 42+/-108 h vs. overdrive 99+/-254 h, P=ns). In conclusion, atrial overdrive pacing, achieved by increasing the atrial base rate, has no incremental benefit in the suppression of paroxysmal atrial fibrillation when compared to rate responsive pacing with a base rate of 60 bpm.

Aged↗
PubMed2000

A comparison between passive and active fixation leads in the coronary sinus for biatrial pacing: initial experience.

AIMS: It has been reported that biatrial pacing can prevent the recurrence of atrial fibrillation. This technique requires a stable coronary sinus (CS) lead position for left atrial pacing. We report our experience of CS pacing with a specifically designed lead [Medtronic 2188 (n= 19)] and active fixation leads [Pacesetter Tendril (n=3), Medtronic Capsurefix (n=6)] in 21 patients with paroxysmal atrial fibrillation and a normal mean left atrial size of 39 mm (range 33-54 mm). METHODS AND RESULTS: Using the Medtronic 2188 lead, successful initial CS canulation and lead positioning was achieved in all 19 patients. One patient developed subclavian vein thrombosis 3 months after initial implant. Eight patients (42%) experienced subsequent lead displacement (12 displacements in total). Of these, seven had their lead replaced with active fixation leads. In addition, two patients underwent active fixation lead implantation at first implant. CS canulation and lead positioning was successful in all nine patients. No patient suffered displacement of an active fixation lead. There were no complications in this group. Twelve of the 19 (66%) Medtronic 2188 leads were functioning at long-term follow-up (11 +/- 4 months) with a biatrial pacing threshold of 2.4 +/- 1 V. Eight of the nine (89%) active fixation leads were functioning at long-term follow-up (6 +/- 3 months) with a biatrial pacing threshold of 2.9 +/- 1.1 V. Using a combined approach 95% of patients had a functioning CS lead at long-term follow-up. CONCLUSION: Active fixation leads can safely be used for left atrial pacing via the CS with good long-term pacing thresholds and stability.

Aged↗