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L T Cooper

Publications and source records attributed to L T Cooper.

At least 19 recordsLinked to original sources
PubMed2004

Predictors of left ventricular dysfunction in patients with Takayasu's or giant cell aortitis.

OBJECTIVES: The aim of this study was to determine the clinical and angiographic predictors of left ventricular systolic dysfunction (LVSD) from a relatively large and angiographically characterized Takayasu's or Giant Cell aortitis (TA/GCA) population. BACKGROUND: LVSD in patients with TA/GCA has been described in case reports and attributed variously to hemodynamic and immunologic factors. The predictors of LVSD in patients with angiographically confirmed TA/GCA are not known. METHODS: We identified 78 patients with angiographically confirmed TA/ GCA that underwent transthoracic echocardiography (TTE) at Mayo Clinic. Echocardiograms were then reviewed independently by reviewers blinded to clinical and angiographic data. LVSD was defined as an ejection fraction (LVEF) less than 50%. RESULTS: The study population was 84% Caucasian (54/78), 91% female (58/78), and had a mean age of disease onset of 30 years (+/- 15 years). LVSD was present in 14 of 78 patients (18%) with TA/GCA. The mean LVEF in the LVSD group (n = 14) was 37% +/- 7%, compared to an LVEF of 62% +/- 6% (p < 0.0001) in those without LVSD (n = 64). LVSD was not associated with hypertension or aortic regurgitation (p > 0.5). However, LVSD was found in 43% (9/21) of patients with aortic arch involvement, versus only 9% (5/57) of patients without aortic arch involvement (p = 0.0013). Patients with LVSD had a median of 2 (range 1-4) involved aortic segments compared to a median of 1 (range 1-4) among those without LVSD (p = 0.013). CONCLUSIONS: In TA/GCA aortitis, LVSD is associated with involvement of the aortic arch and with the greater extent of aortic involvement. The hemodynamic variables, aortic regurgitation and systemic hypertension, were not associated with LVSD, consistent with reports that cardiac inflammation is responsible for LVSD in a majority of cases. Ours is the first study to estimate an incidence of LVSD in patients with TA/GCA aortitis, which was 18%.

Adult↗
PubMed2001

Recombinant tissue plasminogen activator for the treatment of cutaneous infarctions in antiphospholipid antibody syndrome: a case report.

Antiphospholipid antibody syndrome (APAS) commonly presents with cutaneous infarctions mimicking thromboembolic vaso-occlusive disease. Systemic anticoagulation is the standard of care for this disorder, but treatment failures can occur. The authors report the first successful treatment of cutaneous infarctions due to APAS with low-dose, intravenous tissue plasminogen activator (rTPA) in a patient who failed to improve with high-dose anticoagulation. Wound healing was associated with a marked improvement in blood flow as assessed by scanning laser Doppler. The authors recommend that patients presenting with cutaneous infarctions in the absence of atherosclerosis be evaluated for APAS, and that fibrinolytic therapy be considered if cutaneous infarction persists despite anticoagulant therapy.

Aged↗
PubMed2001

Proteinuria in a placebo-controlled study of basic fibroblast growth factor for intermittent claudication.

Intermittent claudication is the most common symptom of peripheral arterial disease (PAD), in part due to an inadequate rise in limb blood flow with exercise. Claudication causes a severe impairment in functional capacity and quality of life in over 3 million Americans. Basic fibroblast growth factor (bFGF) stimulates angiogenesis in vivo and improves limb blood flow in several animal models of hindlimb ischemia. However, the relative safety and efficacy of angiogenic molecules in the treatment of claudication has not been fully evaluated in prospective, blinded clinical trials. In this study, a randomized, double-blind, placebo-controlled, phase II trial of recombinant human bFGF for the treatment of intermittent claudication was performed. bFGF was administered weekly by intravenous infusions of 2 microg/kg for 6 sequential weeks (total dose 12 microg/kg). The primary efficacy endpoint was change in peak walking time (PWT) on a graded exercise treadmill protocol. Secondary efficacy endpoints included changes in functional status as measured by validated questionnaires. The study was stopped prematurely after treatment of the first 24 subjects due to proteinuria in five of the 16 subjects who received systemic bFGF, which exceeded 1000 mg/24 h in four of these five subjects. The small sample size limited evaluation of the predefined efficacy endpoints; however, there was no significant difference between the treatment and control groups for any of the measures of efficacy. In conclusion, intravenous administration of bFGF delivered at low doses weekly for 6 weeks was associated with a high rate of severe proteinuria. It is speculated that bFGF-related proteinuria in this study was primarily related to the systemic route of administration and the frequent dosing schedule. Future clinical trials of bFGF protein should carefully monitor renal function and consider alternative dosing schedules and drug administration routes.

Aged↗
PubMed2001

Current role of endomyocardial biopsy in the management of dilated cardiomyopathy and myocarditis.

Dilated cardiomyopathy is a common cause of congestive heart failure. Despite a thorough cardiovascular evaluation, a specific cause is frequently not found, and the disorder then is considered idiopathic. Endomyocardial biopsy (EMB) may yield diagnostic and prognostic information in patients with idiopathic dilated cardiomyopathy; however, the yield of useful information with this procedure among patients with heart failure is low, and the risks of occasional cardiac perforation and death further limit its use. Recent publications in the field of myocarditis and cardiomyopathy have renewed interest in the use of EMB in select patients to diagnose specific and potentially treatable myocarditides; however, the role of EMB in the work-up of patients with dilated cardiomyopathy is not well defined. In this article, we discuss the risks and utility of EMB in the management of patients with dilated cardiomyopathy and specific myocarditides.

Aged↗
PubMed2000

Giant cell myocarditis: diagnosis and treatment.

Giant cell myocarditis is a rare but devastating disease that usually affects young otherwise healthy individuals. Associations with thymoma, inflammatory bowel disease, and a variety of autoimmune disorders have been reported. The rate of death or heart transplantation is approximately 70% at 1 year. Data from a Lewis rat model and from observational human studies suggest that giant cell myocarditis is mediated by T lymphocytes and may respond to treatment aimed at attenuating T cell function. Recent findings from the Giant Cell Myocarditis Registry, a clinical and pathologic database from 63 cases of giant cell myocarditis gathered from 36 medical centers, include the following: The sensitivity of endomyocardial biopsy for giant cell myocarditis for patients who undergo transplantation or autopsy is 82 to 85%. Registry subjects who received cyclosporine in combination with steroid, azathioprine, or muromonab-CD3 have prolonged transplant-free survival (12.6 months vs. 3.0 months for no immunosuppression). Post-transplantation survival is approximately 71% at 5 years despite a 25% rate of giant cell infiltration in the donor heart. To confirm and extend these findings, a randomized trial of immunosuppression including muromonab-CD3, cyclosporine, and steroids is underway.

Adult↗
PubMed1999

Combined immunosuppression for the treatment of idiopathic giant cell myocarditis.

Giant cell myocarditis (GCM) is a rare and frequently fatal disorder with no proven treatment. Case reports and data from a rat model of GCM suggest that immunosuppressive therapy directed against T lymphocytes may have clinical benefit. We describe a 47-year-old man with severe acute heart failure due to GCM in whom the left ventricular ejection fraction normalized and the myocardial inflammatory infiltrate resolved rapidly after treatment with muromonab-CD3, cyclosporine, azathioprine, and corticosteroids. Three previously published cases with less impressive responses to treatment including muromonab-CD3 and a critical review of the published data on immunosuppressive therapy are included in this report. The response to immunosuppressive therapy is highly variable, and direct comparisons between immunosuppressive regimens do not exist. Therefore, despite individual reports of dramatic improvement after immunosuppressive treatment, firm conclusions cannot be made about the benefit of immunosuppression for GCM. The benefits of immunosuppressive therapy must be confirmed in a prospective, randomized trial.

Adult↗
PubMed1997

Idiopathic giant-cell myocarditis--natural history and treatment. Multicenter Giant Cell Myocarditis Study Group Investigators.

BACKGROUND: Idiopathic giant-cell myocarditis is a rare and frequently fatal disorder. We used a multicenter data base to define the natural history of giant-cell myocarditis and the effect of treatment. METHODS: We identified 63 patients with idiopathic giant-cell myocarditis through journal announcements and direct mailings to cardiovascular centers worldwide. RESULTS: The patients consisted of 33 men and 30 women with an average age of 42.6 years; 88 percent were white, 5 percent were black, 5 percent were Southeast Asian or Indian, and 2 percent were Middle Eastern. Most presented with congestive heart failure (47 patients, or 75 percent), ventricular arrhythmia (9 patients, or 14 percent), or heart block (3 patients, or 5 percent), although in some cases the initial symptoms resembled those of acute myocardial infarction (4 patients). Nineteen percent had associated autoimmune disorders. The rate of survival was worse than among 111 patients with lymphocytic myocarditis in the Myocarditis Treatment Trial (P<0.001); among our patients, the rate of death or cardiac transplantation was 89 percent, and median survival was only 5.5 months from the onset of symptoms. The 22 patients treated with corticosteroids and cyclosporine, azathioprine, or both therapies survived for an average of 12.3 months, as compared with an average of 3.0 months for the 30 patients who received no immunosuppressive therapy (P=0.001). Of the 34 patients who underwent heart transplantation, 9 (26 percent) had a giant-cell infiltrate in the transplanted heart and 1 died of recurrent giant-cell myocarditis. CONCLUSIONS: Giant-cell myocarditis is a disease of relatively young, predominantly healthy adults. Patients usually die of heart failure and ventricular arrhythmia unless cardiac transplantation is performed. Despite the possibility of fatal disease recurrence, transplantation is the treatment of choice for most patients.

Adolescent↗
PubMed1995

Expression of the p16 and p15 cyclin-dependent kinase inhibitors in lymphocyte activation and neuronal differentiation.

The cyclin-dependent kinase inhibitors p16INK4/MTS1 and p15INK4B/MTS2 have been mapped to a region in chromosome 9 (921) that is deleted frequently in acute lymphoblastic leukemias and malignant gliomas. To gain insight into the functions of these inhibitors in lymphocytes and neuronal cells, we studied the expression of p15 and p16 during lymphocyte mitogenesis and neuronal differentiation. Expression of p15 was extinguished during lymphocyte activation, concomitant with an increase in retinoblastoma kinase activity. The differentiation of the embryonic teratocarcinoma cell line NT2 into postmitotic neurons (hNT) was associated with enhanced expression of p15 and p16 proteins. These findings suggest that p15 and p16 play a role in maintaining cell quiescence in lymphocytes and neuronal cells, respectively. Deletions of these genes may thus promote unrestrained growth.

Base Sequence↗
PubMed1994

Accidental defibrillation of the cranium.

The potential dangers of electricity and its use in the clinical setting are obvious. When clinical equipment is taken out of the clinical setting, machine malfunction or unexpected function in the hands of untrained and unskilled individuals can yield disasterous results. The benefits of community education must be weighed carefully in light of the potential danger.

Accidents↗