Determinants of midterm outcome of partial left ventriculectomy in dilated cardiomyopathy

The objective of this study was to test the hypothesis that maternal CRH concentrations are elevated in women experiencing threatened preterm labor who subsequently give birth within 24 h compared to those in women who do not. We also characterized the changes in maternal plasma cortisol, ACTH, corticosteroid binding capacity (CBC), and CRH concentrations in 28 healthy pregnant women between 20-38 weeks gestation. Overall, maternal plasma CRH concentrations were significantly greater (P < 0.05) in those women giving birth within 24 h (1343.3 +/- 143.9 pg/mL; n = 81) compared to those in women who did not (714.5 +/- 64.8 pg/mL; n = 144) or those in normal subjects. This difference was present between 28-36 weeks, but not 24-28 weeks gestation. The ratio of maternal cortisol to CBC was also significantly greater (P < 0.05; 0.65 +/- 0.04; n = 82) in women giving birth within 24 h than in those who did not (0.55 +/- 0.02; n = 136). This difference was significant at all gestational ages studied. Elevated CRH concentrations and bioavailability of free cortisol may both be implicated in the pathogenesis of preterm labor in some women. Further prospective clinical trials are warranted to determine the positive and negative predictive values of maternal CRH concentrations and/or the ratio of cortisol/CBC for identifying women with threatened preterm labor destined to give birth within 24 h.     

Effects of partial left ventriculectomy on left ventricular performance in patients with nonischemic dilated cardiomyopathy

OBJECTIVES: This study sought to assess the effects of partial left ventriculectomy (PLV) on left ventricular (LV) performance in a series of consecutive patients with nonischemic dilated cardiomyopathy. BACKGROUND: Reduction of LV systolic function in patients with heart failure is associated with an increase of LV volume and alteration of its shape. Recently, PLV, a novel surgical procedure, was proposed as a treatment option to alter this process in patients with dilated cardiomyopathy. METHODS: We studied 19 patients with severely symptomatic nonischemic dilated cardiomyopathy, before and 13+/-3 days after surgery, and 12 controls. Single-plane left ventriculography with simultaneous measurements of femoral artery pressure was performed during right heart pacing. RESULTS: The LV end-diastolic and end-systolic volume indexes decreased after PLV (from 169 to 102 ml/m2, and from 127 to 60 ml/m2, respectively, p < 0.0001 for both). Despite a decrease in LV mass index (from 162 to 137 g/m2, p < 0.0001), there was a significant decrease in LV circumferential end-systolic and end-diastolic stresses (from 277 to 159 g/cm2, p < 0.0001 and from 79 to 39 g/cm2, p = 0.0014, respectively). Ejection fraction improved (from 24% to 41%, p < 0.0001); the stroke work index remained unchanged. CONCLUSIONS: The PLV improves LV performance by a dramatic reduction of ventricular end-systolic and end-diastolic stresses. Further studies are needed to assess whether this effect is sustained during long-term follow-up and to define the role of PLV in the treatment of patients with dilated cardiomyopathy.     

Two-year experience of the Batista operation for non-ischemic cardiomyopathy

A temporal reproduction task is composed of two temporal estimation phases: encoding of the interval to be reproduced, followed by its reproduction. The effect of short-term memory processing on each of these phases was tested in two experiments. In Exp. 1, a memory set was presented, followed by two successive tones bounding the target interval to be reproduced. During the reproduction of the target interval, a probe was presented, and the subject ended the reproduction by pressing one of two keys, depending on the presence or absence of the probe in the memory set. In Exp. 2, probe recognition was required during the encoding of the interval to be reproduced. Whereas in Exp. 1 reproductions lengthened as a function of memory-set size, in Exp. 2 temporal reproductions decreased with set size. These results support attentional models of time estimation and suggest that short-term memory processing interrupts concurrent accumulation of temporal information.     

Effects of partial ventriculectomy on left ventricular mechanical properties, shape, and geometry in patients with dilated cardiomyopathy

This study evaluated the 6-month clinical response to sustained-release tetracycline fibers used alone or with scaling and root planing in 25 adult periodontal maintenance patients. All subjects had at least one pocket > or = 4.0 mm that bled on probing and required therapy. Thirty-six teeth were treated with tetracycline fibers for 7 to 12 days; twelve of the 36 teeth also received scaling and root planing. The selection of teeth for scaling and root planing was based on the condition of the teeth. Therapeutic results were evaluated by changes in probing depth and frequency of bleeding on probing. Use of tetracycline fibers and fibers with scaling produced 1.8- and 1.7-mm reductions in probing depth, respectively, 1 month after treatment; reductions declined to 1.3 and 0.8 mm at 3 months, but rebounded to 1.5 and 1.3 mm at 6 months. The percentage of teeth exhibiting bleeding on probing decreased from 100% at baseline to 68% and 50% in the fiber and fiber plus scaling groups, respectively, at 6 months. None of the differences was statistically significant. Tetracycline fibers clearly decreased clinical signs of periodontal inflammation. Addition of scaling and root planing at the time of fiber placement further decreased, although not significantly, the degree of inflammation.     

Partial left ventriculectomy for idiopathic dilated cardiomyopathy: early results and six-month follow-up

BACKGROUND: Recent reports show that partial left ventriculectomy improves hemodynamic and functional status in patients with dilated cardiomyopathy. This study sought to determine the effects of partial left ventriculectomy on clinical outcome and left ventricular function during 6-month follow-up. METHODS: Twenty-two patients underwent partial left ventriculectomy. Mitral valve repair was performed whenever possible, otherwise the valve was replaced. Hemodynamic and functional data were obtained at baseline, as well as 2 weeks and 6 months postoperatively. RESULTS: Overall, 7 of 22 patients died; there were three early and four late deaths. One-year survival was 68%+/-10%. Ejection fraction increased from 23.9%+/-6.8% before the operation to 40.7%+/-12.5% at 2 weeks and to 36.8%+/-7.7% at 6 months (p<0.001, for both). The cardiac index before the operation, at 2 weeks, and at 6 months was 2.3+/-0.8, 2.9+/-0.6, and 3.4+/-1.0 L/m2 per minute, respectively (p = 0.035, and p = 0.009, compared with baseline). The increase in ejection fraction 2 weeks postoperatively was less in patients with left circumflex artery dominance (10.9%+/-3.2% compared with 19.9%+/-10.7%, respectively, p = 0.017). At 6-month follow up, all surviving patients except one improved New York Heart Association functional class when compared with preoperative status (from 3.8+/-0.4 to 1.4+/-0.6, p = 0.0002). CONCLUSIONS: Early hemodynamic improvement after partial left ventriculectomy was maintained during midterm follow-up.     

Technical considerations in the use of the membrane oxygenator (Lande'-Edwards) for open heart surgery

Experience has shown that successful cardio-pulmonary bypass depends upon an efficient oxygenator which causes minimum blood damage. Experience with 1,600 Lande'-Edwards membrane oxygenators in more than 1,000 patients has led to the development of a simple and safe routine for their use in open heart surgery. The circuitry, method of preparation for perfusion, and management of perfusion are described in detail.     

Partial left ventriculectomy for end stage dilated cardiomyopathy. Is it an alternative for heart transplantation?

Incidence of unsuccessful anesthesia with the Gow-Gates mandibular block may be greater than that for the inferior alveolar nerve block until the administrator gains experience with this technique. The aim of this study was to develop a support instrument for the Gow-Gates mandibular block in an attempt to make the described procedure easier and more precise, especially for beginners. In a preliminary clinical experiment 40 patients were anesthetized with this new device; a control group of 40 patients was anesthetized without the instrument. The operators were 80 dental students without previous clinical experience in the Gow-Gates technique. In the experimental group 39 (97.5%) of the 40 patients were provided with complete anesthesia. In the control group 31 (77.5%) of the 40 patients were completely anesthetized. It appears that the new device allows a great level of success with the Gow-Gates mandibular block, irrespective of the clinical experience of the operator.     

Mechanical considerations for the implant tooth-supported fixed partial denture

The implant tooth-supported fixed partial denture presents a biomechanical design problem, because the implant is rigidly fixed within the alveolus, and the tooth is surrounded by a periodontal ligament that allows movement. Nonrigid fixed partial denture designs are advocated by some dentists as a method of compensating for this differential movement. Rigid fixed partial denture designs, however, are advocated by many clinicians. Studies have failed to show the advantage of one design over the other. This study developed an in vitro method for testing such prosthesis designs and measured movement of a natural tooth abutment during simulated function. The movement of the natural tooth abutment was not found to change substantially with the fixed partial denture designs tested.     

Methodologic considerations for research in traditional (alternative) medicine

Repetitive electrical field stimulation evoked muscle contractions of the isolated mouse detrusor strips, which could be abolished by tetrodotoxin (TTX). Both Mn2+ and Ni2+ (0.01-0.06 mM) enhanced neurogenic detrusor contractions in high Ca2+ (5 mM) medium. The non-cholinergic component of the evoked detrusor contractions (in the presence of atropine) was specifically sensitive to this enhancing effect by either Mn2+ or Ni2+. In contrast, the cholinergic component in alpha,beta-methylene ATP-treated detrusors remained unaffected. As compared with Mn2+ and Ni2+, other metal ions, Cu2+, Co2+, Cd2+ and UO2(2+), failed to enhancing the non-cholinergic component of neurogenic detrusor contractions. Nitric oxide synthase (NOS) inhibitors, NG-nitro-L-arginine methyl ester and 7-nitroindazole (a selective neuronal NOS inhibitor) markedly inhibited the enhancing effect by either Mn2+ or Ni2+ on the neurogenic detrusor contractions. Moreover, Mn2+ and Ni2+ did not affect the contractions induced by either carbachol or alpha,beta-methylene ATP. It is concluded from these findings that the neuronal NOS-NO generation pathway is apparently involved in the enhancing effect of Mn2+ and Ni2+ on the muscle contractions elicited by excitatory non-cholinergic neurotransmission in the mouse detrusor strips.     

Dynamic stiffness and implications for assisting the operation of the left ventricle

The distribution of bending strain and stiffness in the wall of the left ventricle (LV) is relevant to the augmentation of its function by a modified skeletal-muscle wrap in the new surgical procedure of cardiomyoplasty. A novel approach to ventricular mechanics is presented which blends some finite-element results in engineering with new data available on ventricular geometry. Two simplified axisymmetric strip-element models of the LV are used to illustrate aspects of myocardial stiffness in the bending-strain-energy distribution and the effect on wrap synchronization of a change in cross-fibre stiffness when the heart has nonuniform or ectopic beats. The nonlinear and time-dependent nature of both camping and wall stiffness is derived from differential equations governing the dynamic paths from systole to diastole of finite wall elements around the periphery of an oblique LV slice using magnetic resonance imaging (MRI) data. This leads to a geometric method for determining these parameters. Results for time-dependent stiffnesses of elements in their trajectories are presented for a normal heart.     

Technical modification of moulds construction for gynecological curietherapy (author's transl)

The authors describe a new, faster and less-laborious method of moulds construction for gynecological curietherapy.     

A modification of hepatic portoenterostomy (Kasai operation) for biliary atresia

BACKGROUND AND AIMS: The aim of the present study was to compare power Doppler imaging with traditional color Doppler imaging and with contrast enhanced computer tomography in the evaluation of intratumoral vascularity of hepatocellular carcinomas at diagnosis and in response to percutaneous ethanol injection. PATIENTS AND METHODS: Sixteen patients with hepatocellular carcinoma underwent colour Doppler, power Doppler and computed tomography at diagnosis. Seventeen patients were studied by the three techniques one month after percutaneous ethanol injection treatment. RESULTS: At baseline evaluation, power Doppler and color Doppler were always in agreement and, with the exception of one case, were also in agreement with the computerized tomography scan. On the contrary, power Doppler and computerized tomography are more sensitive than color Doppler in the evaluation of residual vascularized tumoral tissue after percutaneous ethanol injection. In 3 patients, residual vascularity was demonstrated only by computerized tomography while color and power Doppler were negative. In another 3 cases, a positive power Doppler signal, with a typical arterial Doppler spectrum, was observed while color Doppler and computerized tomography were negative. In these patients, cancer relapse was clinically evident after a few months and treatment was repeated to obtain complete necrosis. CONCLUSIONS: We conclude that only the integration of the results of all these techniques can reliably evaluate tumoral vascularity after percutaneous ethanol injection.     

Fetal cells in the maternal circulation. Technical considerations for practical application to prenatal diagnosis

We have used electron-microscopic studies, bromodeoxyuridine (BrdU) incorporation and antibody labeling to characterize the development of the Drosophila larval photoreceptor (or Bolwig's) organ and the optic lobe, and have investigated the role of Notch in the development of both. The optic lobe and Bolwig's organ develop by invagination from the posterior procephalic region. After cells in this region undergo four postblastoderm divisions, a total of approximately 85 cells invaginate. The optic lobe invagination loses contact with the outer surface of the embryo and forms an epithelial vesicle attached to the brain. Bolwig's organ arises from the ventralmost portion of the optic lobe invagination, but does not become incorporated in the optic lobe; instead, its 12 cells remain in the head epidermis until late in embryogenesis when they move in conjunction with head involution to reach their final position alongside the pharynx. Early, before head involution, the cells of Bolwig's organ form a superficial group of 7 cells arranged in a 'rosette' pattern and a deep group of 5 cells. Later, all neurons move out of the surface epithelium. Unlike adult photoreceptors, they do not form rhabdomeres; instead, they produce multiple, branched processes, which presumably carry the photopigment. Notch is essential for two aspects of the early development of the visual system. First, it delimits the number of cells incorporated into Bolwig's organ. Second, it is required for the maintenance of the epithelial character of the optic lobe cells during and after its invagination.     

Senning plus arterial switch operation for discordant (congenitally corrected) transposition

BACKGROUND: Congenitally corrected transposition of the great arteries is a complex cardiac lesion, usually associated with ventricular septal defect, left ventricular outflow tract obstruction, and tricuspid valve abnormalities. A subset of patients without left ventricular outflow tract obstruction have undergone Senning plus arterial switch operation in an attempt to place the left ventricle in the systemic circuit and the right ventricle in the pulmonary circuit. METHODS: Fourteen patients have had the operation performed since July 1989. Age and weight medians were 12 months (range, 0.5 to 120 months) and 8.2 kg (range, 3.2 to 34 kg). All but 1 patient had a left ventricular to right ventricular pressure ratio greater than 0.7, due to a large ventricular septal defect (with or without a previous pulmonary artery band), severe congestive heart failure caused by right ventricular dysfunction and tricuspid insufficiency, or a pulmonary artery band for left ventricular retraining. At least 10 patients had strong contraindications to "classic" repair, including right ventricular hypoplasia (n = 2), moderate to severe right ventricular dysfunction (n = 5), or moderate to severe tricuspid insufficiency (n = 9). RESULTS: There was one hospital death, occurring in a neonate (7%; 95% confidence interval = 0% to 34%). Actuarial survival beyond 10 months is 81% (95% confidence interval = 42% to 95%), currently with 389 patient-months of total follow-up time. The median grade of tricuspid insufficiency fell from 3/4 preoperatively to 1/4 postoperatively (p = 0.003). Right ventricular function is normal in 11/12 current survivors, all but 1 of whom are in New York Heart Association class I or II. CONCLUSIONS: Senning plus arterial switch operation is a good option for selected patients with congenitally corrected transposition of the great arteries with a similar or lower early risk (as compared with classic repairs). Some of the long-term problems associated with congenitally corrected transposition of the great arteries may be avoided with this strategy.