Long Beach Memorial Medical Center

About: Long Beach Memorial Medical Center is a healthcare organization based out in Long Beach, California, United States. It is known for research contribution in the topics: Pregnancy & Randomized controlled trial. The organization has 674 authors who have published 661 publications receiving 28095 citations.

Cardiac Resynchronization in Chronic Heart Failure

Abstract: Background Previous studies have suggested that cardiac resynchronization achieved through atrial-synchronized biventricular pacing produces clinical benefits in patients with heart failure who have an intraventricular conduction delay. We conducted a double-blind trial to evaluate this therapeutic approach. Methods Four hundred fifty-three patients with moderate-to-severe symptoms of heart failure associated with an ejection fraction of 35 percent or less and a QRS interval of 130 msec or more were randomly assigned to a cardiac-resynchronization group (228 patients) or to a control group (225 patients) for six months, while conventional therapy for heart failure was maintained. The primary end points were the New York Heart Association functional class, quality of life, and the distance walked in six minutes. Results As compared with the control group, patients assigned to cardiac resynchronization experienced an improvement in the distance walked in six minutes (+39 vs. +10 m, P=0.005), functional clas...

MR appearance of hemorrhage in the brain.

Abstract: The appearance of intracranial hemorrhage at magnetic resonance (MR) imaging depends primarily on the age of the hematoma and the type of MR contrast (ie, T1 or T2 weighted). As a hematoma ages, the hemoglobin passes through several forms (oxyhemoglobin, deoxyhemoglobin, and methemoglobin) prior to red cell lysis and breakdown into ferritin and hemosiderin. Five distinct stages of hemorrhage can be defined: hyperacute (intracellular oxyhemoglobin, long T1 and T2), acute (intracellular deoxyhemoglobin, long T1, short T2), early subacute (intracellular methemoglobin, short T1, short T2), late subacute (extracellular methemoglobin, short T1, long T2), and chronic (ferritin and hemosiderin, short T2). The short T1 of methemoglobin is due to the paramagnetic dipole-dipole interaction. Another paramagnetic property, the magnetic susceptibility effect, is responsible for the short T2 observed when deoxyhemoglobin, methemoglobin, or hemosiderin is intracellular. T2 shortening can also be produced by hemoconcentration and clot retraction. The T2 shortening due to magnetic susceptibility effects is enhanced on higher-field-strength systems and on gradient-echo images and is reduced with "fast spin-echo" MR techniques.

A comparison of patellar tendon autograft and allograft used for anterior cruciate ligament reconstruction in the goat model

Abstract: Similar-sized patellar tendon autografts and fresh-frozen allografts were used to reconstruct the anterior cruciate ligament of one knee in 40 female goats. Evaluations of the reconstructions and contralateral controls at the 6-week and 6-month postoperative periods included anterior-posterior translation, mechanical properties determined during tensile failure tests, measurement of cross-sectional area, histology, collagen fibril size and area distribution, and associated articular cartilage degenerative changes. Six months after anterior cruciate ligament reconstruction, the autografts demonstrated a smaller increase in anterior-posterior displacement, values of maximum force to failure two times greater, a significant increase in cross-sectional area, a more rapid loss of large-diameter collagen fibrils, and an increased density and number of small-diameter collagen fibrils compared to the allografts. Clinical significance. More surgeons are allowing their patients to return to running and sports 6 months after anterior cruciate ligament reconstruction. While the structural and material properties of autografts and allografts at time zero are similar, in the goat model during the first 6 months they differ. The allografts demonstrate a greater decrease in their implantation structural properties, a slower rate of biologic incorporation, and the prolonged presence of an inflammatory response. At 6 months the autograft demonstrates a more robust biologic response, improved stability, and increased strength to failure values.

Comparison of cuffed and uncuffed endotracheal tubes in young children during general anesthesia.

Abstract: BackgroundUncuffed endotracheal tubes are routinely used in young children. This study tests a formula for selecting appropriately sized cuffed endotracheal tubes and compares the use of cuffed versus uncuffed endotracheal tubes for patients whose lungs are mechanically ventilated during anesthesia.

Continued local recurrence of carcinoma 15-25 years after a diagnosis of low grade ductal carcinoma in situ of the breast treated only by biopsy.

Abstract: Background. The stratification of ductal carcinoma in situ (DCIS) of the human breast into prognostically relevant categories by size and histologic pattern is a current concern. Few studies have been able to follow women after the identification of any type of DCIS when they have had biopsy only. Methods. This is an extension of a follow-up study of a group of 28 women with small, noncomedo ductal carcinomas in situ that were excised by biopsy only, published in 1982. All these women have now been successfully followed for an average of almost 30 years. Results. The overall risk of development of invasive carcinoma for these women over almost 30 years is nine times that of the general population (95% confidence interval, 4.7–17). This is similar to the 11-fold elevation in relative risk that was determined after about 15 years of follow-up. All invasive carcinomas have developed in the same area in the same breast. There were two women in whom invasive carcinoma developed between 20 and 30 years after initial biopsy. One other woman had an extensive noncomedo DCIS that was identified 25 years after her initial biopsy, but had no evidence of invasive disease. Conclusion. The natural history of small, noncomedo DCIS can last over at least 2 decades, with invasive carcinoma developing at the same site in which DCIS was previously discovered in a significant percentage of women (broadly, between 25%–50%). This is quite different from the natural history of comedo DCIS or any type of DCIS treated purposefully by surgery alone.