Search PubMedSearch

Biomedical subjects

J M Matloff

Publications and source records attributed to J M Matloff.

At least 19 recordsLinked to original sources

Adverse 5-year outcome after coronary artery bypass surgery in blacks.

BACKGROUND: Coronary heart disease is the leading cause of death among blacks, but little is known about the late results of coronary artery bypass surgery in this population. It is not known whether differences in preoperative medical characteristics or medical health insurance affect outcome. We studied the effects of medical risk factors on survival outcome after coronary artery bypass surgery in a population of medically insured black and white patients. METHODS: Racial status and outcomes from surgery were determined in 3728 consecutive patients who had coronary artery bypass surgery at the authors' institution from January 1, 1984, to June 30, 1992. Coronary artery bypass surgery (excluding valve replacement) was performed in 115 black and 3113 white patients. RESULTS: Late survival probability was worse for blacks than whites at 1 year (84% vs 92%) and at 5 years (64% vs 82%, P=.001, Wilcoxon test). Most deaths were due to cardiac events in both groups (68% in blacks vs 67% in whites). Blacks had more hypertension (84% vs 54%), diabetes mellitus (36% vs 23%), and more were current smokers (21% vs 14%) (all P<.05, Fisher's exact test). Medical insurance coverage for blacks and whites was as follows: Medicare (60% vs 57%), private (38% vs 42%), and Medi-Cal (2% vs 2%). Operative mortality (30 days) was similar (5.2% for blacks vs 4.1% for whites; P=.48, Fisher's exact test). In a Cox regression model, race predicted long-term survival and persisted as an important risk factor after adjusting for preoperative factors related to patient survival (adjusted hazard ratio, 2.10; 95% confidence interval, 1.43 to 3.07). CONCLUSIONS: In this group of predominantly medically insured patients undergoing coronary artery bypass surgery, the risk of death in blacks at 5 years was twice that of whites.

Black or African American

Assessment of pathological changes associated with chronic allograft rejection and tolerance in two experimental models of rat lung transplantation.

Lung transplantation is now routinely performed for a wide range of end-stage cardiopulmonary disorders. Despite overcoming the problems associated with early acute rejection, chronic rejection (CR) in the form of obliterative bronchiolitis has emerged as the primary cause of late graft loss. The mechanisms involved in the development of CR of lung allografts are poorly understood, and no effective therapy is currently available. To better understand the pathological events associated with CR and tolerance, we examined two models of lung allograft rejection established in our laboratory. First, we exchanged left lung allografts between moderately histoincompatible inbred rat strains (WKY-->F344: n = 42 and F344-->WKY: n = 40). The WKY-->F344 model was previously shown to develop spontaneous tolerance, while the converse model (F344-->WKY) showed persistent acute rejection. The purpose of this investigation was to assess histopathological changes associated with long-term grafts left in place up to 140 days after transplant. To confirm that tolerance had developed, skin-grafting experiments were performed. Five skin grafts from each strain were placed on lung allograft recipients on day 35 after transplant and skin allograft survival was assessed and compared with controls. Acute rejection (AR) was graded histologically (stage O-IV) and the pathologic intensity of inflammation and CR were graded (0-4: 0 = 0%, 1 = 1-25%, 2 = 26-50%, 3 = 51-75%, and 4 = 76-100%) on percentage of involvement with the following categories being examined: (a) lymphocytic infiltration (perivascular, peribronchial, and peribronchiolar) and (b) vasculitis, edema, hemorrhage, and necrosis. Finally, chronic rejection was diagnosed by the presence of intimal hyperplasia, interstitial fibrosis, peribronchiolar fibrosis, bronchiolitis obliterans, and bronchiectasis. The WKY-->F344 animals showed progressive AR (stage III, day 21). Thereafter, the AR subsided spontaneously and was stage 0 on day 140. There were no signs of CR in these animals. In the F344-->WKY model, the AR progressed up to stage III-IV (day 21) and maintained for several weeks at stage III. Thereafter, pictures of the lungs showed CR on days 49, 70, and 98. There were significant differences between the two models during the chronic phase, such as interstitial fibrosis (0 +/- 0 vs. 1.8 +/- 1.3, P < 0.005), peribronchiolar fibrosis (0 +/- 0 vs. 3.6 +/- 0.55, P < 0.01), vasculitis (0.2 +/- 0.45 vs. 2.0 +/- 0, P < 0.008), and intimal hyperplasia (0.2 +/- 0.45 vs. 2.6 +/- 0.9, P < 0.008).(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Disease

Soluble CTLA4Ig modifies parameters of acute inflammation in rat lung allograft rejection without altering lymphocytic infiltration or transcription of key cytokines.

The efficacy of CTLA4Ig in blocking immune activation and allograft rejection (AR) was tested in an aggressive and rapid model of rat lung AR (Brown Norway [BN]-->Lewis [LEW]). CTLA4Ig is a recombinant soluble protein that binds with high affinity to rat B7/BB1 and other surface molecules on APCs, subsequently blocking the binding of B7/BB1 to CD28/CTLA4 on T cells. This interrupts the costimulatory pathway critical for complete T cell activation and completion of the AR process. Left single-lung transplants were performed between BN-->Lew. Five allograft recipients were examined in each group. At transplantation, animals received 250 micrograms of CTLA4Ig or 250 micrograms of control Ig intraperitoneally daily until sacrifice. Animals were sacrificed on days 2, 4, and 7 after transplant. Control (BN-->Lew) grafts show irreversible rejection by day 7. Syngeneic (Lew-->Lew) grafts show no AR on day 7. AR episodes were graded histologically (stages 0-IV) and pathologic intensity of inflammation was graded on percentage of involvement. Cytokine transcript levels were measured in control and CTLA4Ig-treated animals (n = 5 in each group) on day 7 using reverse transcriptase polymerase chain reaction techniques. The most profound differences were found on day 7 after transplant. The degree of lymphocytic infiltration was greater in the CTLA4Ig group (perivascular: 4 +/- 0 vs. 2.6 +/- 0.6, peribronchial: 4 +/- 0 vs. 2.2 +/- 0.4, and peribronchiolar: 3.6 +/- 0.5 vs. 2 +/- 0.3, P < 0.01). However, in striking contrast, the stage of AR (3 +/- 0 vs. 4 +/- 0, P < 0.01), vasculitis (1 +/- 0.7 vs. 2.6 +/- 0.6, P < 0.05), hemorrhage (0.4 +/- 0.6 vs. 3.2 +/- 0.4, P < 0.01), and necrosis (0 +/- 0 vs. 2.4 +/- 0.5, P < 0.005) were significantly reduced in animals treated with CTLA4Ig. Since CTLA4Ig blocks Th1 cell activation in vitro, we compared the levels of Th1 inflammatory cytokines IL-2, gamma-IFN, and TNF-alpha in the two models. The intragraft ratios (CTLA4Ig/control) were IL-2:0.77, gamma-IFN: 1.29, and TNF-alpha:1.33. Thus, CTLA4Ig did not significantly block intragraft production of Th1 cytokines on day 7.(ABSTRACT TRUNCATED AT 400 WORDS)

Abatacept

A cardiothoracic surgery information system for the next century: implications for managed care.

The United States health care system is under tremendous pressure to cut costs while maintaining quality. One mechanism to reduce costs is managed care--a system with both risks and benefits for patients, providers, and payors, and one that requires large volumes of data to ensure optimal medical and financial decision-making. In this review, we describe the types of information needed by managed care systems, including medical outcome data (satisfaction, survival, quality of life, and complications) and financial data (costs and long-term resource utilization). From a provider's point of view, the customers for these data range from individual patients to large self-insured corporations, and we describe the data required for each potential customer. Finally, as a concrete example of how data can be collected and analyzed to improve a provider's competitiveness, we describe the Cedars-Sinai Medical Center cardiothoracic surgery database from a managed care perspective. The concepts presented are generalizable to other subspecialties, and will become more important in the increasingly competitive milieu of American health care.

Cardiac Surgical Procedures

Hospital-based group: ideal practice for the future?

The format for future cardiothoracic surgical practices includes the option of a hospital-based group where provider groups and the hospital share the responsibilities and obligations of clinical care and the cost of that care. Based on personal experience at the Cedars-Sinai Medical Center, Los Angeles, three separate contract relationships during our tenure have reflected the evolution of cardiothoracic surgeons' relationship to our patients and the hospital in which we work. Although other organizational modes may prove equally successful, the hospital-based group practice is a viable structure that supports the preservation of quality in the work performed. This relationship helps to maintain a steady volume of patients enabling research endeavors, which are primarily funded through practice incomes, to continue and it also provides a platform for networking with defined patient referrals, shared services, and bench-marking with other centers.

Contract Services

Optimizing cardiothoracic surgery information for a managed care environment.

The rapid change occurring in American healthcare is a direct response to rising costs. Managed care is the fastest growing model that attempts to control escalating costs through limitations in patient choice, the active use of guidelines, and placing providers at risk. Managed care is an information intensive system, and those providers who use information effectively will be at an advantage in the competitive healthcare marketplace. There are five classes of information that providers must collect to be competitive in a managed care environment: patient satisfaction, medical outcomes, continuous quality improvement, quality of the decision, and financial data. Each of these should be actively used in marketing, assuring the quality of patient care, and maintaining financial stability. Although changes in our healthcare system are occurring rapidly, we need to respond to the marketplace to maintain our viability, but as physicians, we have the singular obligation to maintain the supremacy of the individual patient and the physician-patient relationship.

Capitation Fee

Influence of vein valves in the development of arteriosclerosis in venoarterial grafts in the rabbit.

Coronary saphenous vein grafts in human beings have a more limited long-term patency rate than internal thoracic artery grafts, primarily because of more rapid development of arteriosclerosis. The factors responsible for this increased susceptibility are not completely understood. To test the hypothesis that vein valves may influence this process, we studied 48 hypercholesterolemic rabbits with jugular vein grafts interposed into the carotid arterial circulation. In 24 animals (group A), the vein segments did not contain a vein valve. In the other 24 animals (group B), a vein valve was present. Both groups were further divided in four subgroups of six to be put to death at 2, 4, 6, and 8 weeks after the operation. All animals were fed a 2% cholesterol diet. At postmortem examination, alternate 2 mm sections were either stained with hematoxylin and eosin for histologic and morphometric studies or frozen in liquid nitrogen for immunohistochemistry and in situ hybridization studies. Proliferating cell nuclear antigen immunostaining was used to study cell proliferation. Wall thickness of vein grafts increased with time. During the first 2 weeks intimal and medial thickening was primarily due to an increase in numbers of cells. Between 2 and 6 weeks further intimal and medial thickening occurred, but without additional increase in cell numbers. After 6 weeks, foam cells and lipid deposits started to appear. By 8 weeks, changes identical to those seen in arteriosclerotic plaques in human beings were evident. These changes developed sooner and with more intensity in group B animals (p < 0.01 to 0.001), and they developed faster and with more severity in segments of vein located distal to the valve than in the segments located proximal to the valve (p < 0.001). This is the first controlled experiment demonstrating that the presence of valves in the vein segments is associated with augmented and accelerated intimal changes leading to vein atheromatosis.

Animals

Postinfarction ventricular septal defect in the elderly: analysis and results.

Fifteen elderly patients (age more than 70 years) underwent surgical repair of postinfarction ventricular septal defects during the years 1980 through 1992. The operative (to discharge or < 30 days) mortality rate was 47%, and the complication rate among survivors was 63%. The probability of survival at 1 year was 47% +/- 13%. Because of the small sample size of our patient population, predictive preoperative risk factors associated with early mortality could not be identified with certainty. However, there is a trend suggesting that high right atrial pressures (p = 0.15) and the need of an intraaortic balloon pump preoperatively (p = 0.12) influence 30-day mortality, as previously described in larger series. Of 5 long-term survivors, 3 are in New York Heart Association functional class I and 2 are in class II. Our experience in this group of patients suggests that in the elderly, a very aggressive approach should be taken in recommending early surgical intervention for postinfarction ventricular septal defect before hemodynamic deterioration ensues and severely compromises chances for survival.

Aged

Ten-year experience of cardiac surgery in patients aged 80 years and over.

Five hundred twenty-eight consecutive patients aged 80 years and over (mean age, 83.1 +/- 2.7 years) underwent cardiac operations with hypothermia (mean, 21.9 degrees +/- 2.2 degrees C), hyperkalemic cardioplegia, and cardiopulmonary bypass in a 10-year period. Fifty-six percent of the patients were male. Preoperatively, 68% of the patients were in New York Heart Association functional class IV, and 31% were in class III. Among them, 303 patients had isolated coronary artery bypass grafting (CABG) (group I), 132 had aortic valve replacement only or combined with CABG (group II), 42 had mitral valve replacement only or combined with CABG (group III), 31 had mitral valve repair and CABG (group IV), and 20 had double-valve procedure only or combined with CABG (group V). The 30-day or in-hospital mortality was 8.3% in group I, 4.5% in group II, 29% in group III, 23% in group IV, and 30% in group V. Total 30-day or in-hospital mortality was 10.6%. One-year and 5-year actuarial survival rates were as follows: group I, 82% and 62%; group II, 85% and 58%; group III, 61% and 37%; group IV, 56% and 19%; and group V, 63% and 15%. Total 1-year and 5-year actuarial survival were 79% and 54%. At follow-up (mean, 2 years), 70% of overall survivors reported that their general health had improved. Our experience demonstrates that for select patients aged 80 years and over with unmanageable cardiac symptoms, CABG and aortic valve replacement groups had better results in improving quality of life as compared with patients having mitral or combined procedures.

Actuarial Analysis

Long-term survival after coronary artery bypass grafting.

The most quoted long-term outcome studies from the coronary artery bypass surgery literature were performed in the 1970s, and these trials--the Coronary Artery Surgery Study, the Veterans Administration Study, and the European Cooperative Study--added significantly to our knowledge of the efficacy of bypass surgery. However, important studies are still being performed and are refining our knowledge of long-term outcomes. This review covers early factors that affect long-term outcome, and recent information concerning particular subgroups of patients undergoing bypass surgery. In addition, new information is becoming available about the relative roles of percutaneous transluminal coronary angioplasty and coronary artery bypass grafting, and these studies are also discussed.

Angioplasty, Balloon, Coronary

Anemia therapy: individual benefit and societal cost.

The US health care system is under increasing pressure to lower costs while maintaining quality of care. Providers will be forced to (1) measure the benefits of a particular therapy, and (2) demonstrate that the benefits justify the costs. The major components of therapeutic benefit are survival and quality of life. Chronic anemia may have little impact on survival, but studies have measured significant decrements in quality of life without therapy and increments in quality of life with therapy. This disease also presents important societal financial concerns due to its many competing therapies. The annual cost of treatment can vary from an average of a few dollars for iron supplementation to an average of $6,000 for a course of recombinant human erythropoietin. Physicians need to integrate information on therapeutic outcomes and cost to maximize individual benefit and justify the costs. The choice of therapy for anemia associated with cancer is complex because the onset of the anemia is multifactorial, and the effects of anemia may be masked by the underlying malignancy. There are insufficient data supporting a specific recommendation for transfusion or recombinant human erythropoietin therapy. The current cost-conscious environment in the United States presents an opportunity for health care providers to formally document the benefits of anemia therapy and justify the societal costs based on those benefits. Anemia is an excellent example of a condition that allows the formal analysis of disease impact and the effectiveness and cost of therapy because (1) it has multiple therapies, (2) the cost of therapy varies widely, and (3) the therapies have variable benefit depending on the individual patient. Using a model based on chronic renal failure, an outcomes structure was developed by which the impact of anemia and the therapies used to manage it can be measured. Its potential application to anemia in patients with cancer is discussed.

Anemia

Immunocytologic analysis of cells obtained from bronchoalveolar lavage in a model of rat lung allograft rejection.

Left lung transplantation (n = 30) between BN rat (RT1n) and LEW rat (RT1(1)) was performed to examine serial changes in the inflammatory cell profile and T-cell subsets occurring in bronchoalveolar lavage (BAL) obtained after transplantation. Transplanted animals were sacrificed on Days 1 to 7 post-transplantation. Previous studies show that lung allografts between these rat strains were strongly rejected within 7 days. The serial change in the cell profile of BAL showed a marked initial predominance of polymorphonuclear leukocytes, a decrease in macrophages, and a temporary increase in number of eosinophils on Day 2 post-transplantation. A gradual increase in lymphocytes coincident with progression of rejection was also noted. Immunocytologic studies using monoclonal antibodies specific for rat T-cell subsets and interleukin-2 receptor (IL-2R) showed significant increase in pan-T-cells on Days 3, 4, and 5 and T-suppressor/cytotoxic (CD8 positive) fraction on Days 4 and 5, whereas the T-helper (CD4 positive) fraction peaked on Day 2. The frequency of T-cells expressing IL-2R (55 kDa), indicating activated T-cells, significantly increased as early as Day 2 and maintained its high value thereafter. mRNA levels for IL-2R were detectable in the allografts on Day 2 and peaked on Day 5 post-transplantation. The value of CD4/CD8 T-cell ratios rose initially and then dropped below 1.0 on Days 4 and 5. These values differed markedly from those of syngeneic transplants (Lew-->Lew) examined on Day 5 post-transplantation. First, no significant changes in BAL cytology were seen when syngeneic transplants were compared with normal (Lew) lung.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals

Fee-for-benefit: a strategy to improve the quality of health care and control costs through reimbursement incentives.

OBJECTIVES: The purpose of this study was to determine whether reimbursement in direct proportion to expected therapeutic benefit is capable of improving the utilization and cost of health care. BACKGROUND: The benefit associated with a particular medical or surgical treatment varies widely from patient to patient. Nevertheless, payment to the provider of the treatment is essentially invariant under the current fee-for-service system. Under an alternative fee-for-benefit strategy, empiric data are used to construct a multivariate model to predict the expected benefit to an individual patient from a particular health care service on the basis of conventional clinical descriptors. The payers and the providers of the service then openly negotiate an explicit economic relation between expected benefit and monetary payment such that payment is directly proportional to benefit. METHODS: Computer simulations were performed to determine the potential impact of this fee-for-benefit strategy with respect to medical versus surgical treatment of coronary artery disease. RESULTS: Compared with conventional fee-for-service, fee-for-benefit resulted in a 12% improvement in patient benefit (quality-adjusted survival), a 22% reduction in provider payments and a 55% increase in cost/benefit (the ratio of benefit to payment). CONCLUSIONS: The incentives embodied in a fee-for-benefit strategy can be an effective mechanism for encouraging more appropriate health care utilization while simultaneously controlling health care costs.

Actuarial Analysis

The St. Jude valve. Thrombolysis as the first line of therapy for cardiac valve thrombosis.

BACKGROUND: Thrombolytic therapy is a promising alternative to valve replacement in the management of prosthetic valve thrombosis. We sought to determine the short- and long-term results of treating thrombosed St. Jude heart valves with thrombolytic therapy as the primary treatment modality. METHODS AND RESULTS: Between March 1978 and December 1991, 988 patients underwent implantation of St. Jude prosthetic valves at our medical center, and all patients with thrombosed valves were identified prospectively. During this period, 17 patients (13 women; mean age, 66.8 +/- 19.0 years) developed prosthetic valve thrombosis (11 aortic, six mitral). In six patients, Coumadin was stopped in preparation for elective surgery. The clinical presentation was congestive heart failure in 13, syncope and fatigue in two, and a cerebrovascular accident in one; one patient was asymptomatic. The average duration of symptoms was 11.7 +/- 12.0 days (range, 1-45 days). Anticoagulation was subtherapeutic in all but one patient at the time of presentation. Cinefluoroscopy was the primary method used for diagnosis and was also used to follow the response to therapy. Twelve patients were treated medically (10 with thrombolytic therapy and two with heparin), three were treated surgically, and two were diagnosed at autopsy. Of the 12 medically treated patients, 10 had marked improvement in leaflet movement and symptoms within 12 hours. Thus, 10 of 12 patients (83%) had a satisfactory response to medical therapy alone. No medically treated patient died or had a major complication resulting in permanent damage. However, four of the 12 medically treated patients had minor complications, including a transient episode of facial weakness in one patient, hematomas in two, and epistaxis in one. Late rethrombosis recurred in two patients in the medically treated group and was successfully retreated with thrombolytic therapy. At 3 months, all patients were alive and well. CONCLUSIONS: Thrombolytic therapy can be used as the first line of therapy for thrombosed St. Jude valves with a low risk of permanent side effects and excellent chances of success. In most cases, surgery can be reserved for patients who do not respond to thrombolytic therapy.

Adolescent

Results of early repair of ventricular septal defect after an acute myocardial infarction.

A 10-year experience with early operation for postinfarction ventricular septal defect is reviewed. Twenty-two patients underwent surgical repair; operative mortality was 36% (< 30 days). The actuarial survival was 64% at 1 month, 59% at 1 year, and 47% at 5 years. Risk factors predictive of operative mortality were diabetes (p = 0.001), elevated preoperative right atrial pressure (p = 0.02), the absence of a preoperative intraaortic balloon pump (p = 0.006), and a short time interval between infarct and operation (p = 0.018). Long-term survival was adversely related to diabetes (p = 0.030), elevated preoperative right atrial pressure (p = 0.005), and, surprisingly, survival was better in patients with a greater extent of coronary artery disease (p = 0.023). There were 14 operative survivors (64%) and 11 long-term survivors (3 months to 10 years, mean 6.0 +/- 3.5 years). Six of eleven survivors were in functional New York Heart Association class I, one was in class II, and four were in class III.

Aged