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N Smedira

Publications and source records attributed to N Smedira.

16 recordsLinked to original sources
PubMed2005

Survival beyond 10 years following heart transplantation: The Cleveland Clinic Foundation experience.

BACKGROUND: Long-term survival after heart transplantation is a desirable although challenging goal. METHODS: We analyzed clinical outcomes in the cohort of 170 patients who have undergone heart transplantation at The Cleveland Clinic Foundation and survived >10 years. RESULTS: We found 10-year and 15-year survival rates of 54% and 41%, respectively, in these patients, but there was also a high incidence of complications, such as hypertension, renal dysfunction, transplant vasculopathy, and malignancy. CONCLUSIONS: Long-term survival following cardiac transplantation is possible although complications are frequent. Beyond 10 years, malignancy is a major cause of death.

Adult↗
PubMed2004

The influence of donor gender on allograft vasculopathy: evidence from intravascular ultrasound.

BACKGROUND: Allograft vasculopathy is a major risk factor for mortality following cardiac transplantation. Several immune and nonimmune factors have been evaluated as risk factors for the development of coronary vasculopathy. OBJECTIVE: We evaluated the influence of donor gender on the progression of coronary vasculopathy in heart transplant recipients. METHODS: Eighty-nine heart transplant recipients (67 men, 22 women of mean age: 56 +/- 12 years) underwent serial volumetric intravascular ultrasound analysis (IVUS) at baseline (within 1 month) and at 1 year after transplantation. Patients were divided into four groups in relation to the donor-recipient gender status: female-female, n=17; female-male, n=28; male-female, n=5; male-male, n=39. Ultrasound images were recorded during an automated pullback and with an equal number of slices (average=22 per coronary vessel). The measured IVUS indices for the left anterior descending artery were: change in maximal intimal thickness, average intimal area, total plaque volume, and intimal index. RESULTS: Patients were similar in baseline characteristics. At 1 year after transplantation, IVUS indices of coronary vasculopathy were significantly increased among recipients of female allografts (P <.05). CONCLUSION: Heart transplant recipients of female allografts display increased coronary vasculopathy progression.

Adult↗
PubMed2004

Donor intracranial bleeding is associated with advanced transplant coronary vasculopathy: evidence from intravascular ultrasound.

OBJECTIVES: We evaluated the impact of spontaneous intracranial bleeding (ICB) in the donor on transplant coronary vasculopathy using serial intravascular ultrasound examinations. MATERIALS AND METHODS: Between January 1995 and December 2000, 72 recipients underwent cardiac transplantation from donors who had experienced spontaneous ICB (ICB group). Their findings using serial intravascular ultrasound analysis at baseline (within 1 month) and 1 year after transplantation were compared with 90 recipients who had undergone transplantation from trauma donors (trauma group). RESULTS: Compared with the Trauma group, the ICB group showed increased coronary intimal thickness (0.55 +/- 0.33 vs 0.39 +/- 0.3 mm; P = .034), plaque volume (3.84 +/- 2.5 vs 2.28 +/- 1.65 mm(3); P = .015) and plaque burden (7.4 vs 2%) at 1 year after transplantation. CONCLUSIONS: Donor spontaneous ICB is associated with significantly increased coronary vasculopathy.

Adult↗
PubMed2002

The incidence of invasive aspergillosis among solid organ transplant recipients and implications for prophylaxis in lung transplants.

BACKGROUND: Invasive aspergillosis (IA) is associated with significant morbidity and mortality in solid organ transplant recipients but data on the incidence rates stratified by type of solid organ are limited. OBJECTIVE: To describe the attack rates and incidence of IA in solid organ transplant recipients, and the impact of universal Aspergillus prophylaxis (aerosolized amphotericin B or oral itraconazole) in lung transplant recipients. PATIENTS: The 2,046 patients who received solid organ transplants at the Cleveland Clinic Foundation from January 1990 through 1999 were studied. METHODS: Cases were ascertained through computerized records of microbiology, cytology, and pathology reports. Definite IA was defined as a positive culture and pathology showing septate hyphae. Probable IA was clinical disease and either a positive culture or histopathology. Disseminated IA was defined as involvement of two or more noncontiguous anatomic sites. RESULTS: We identified 33 cases of IA (28% disseminated) in 2,046 patients (attack rate = 1.6%) for an incidence of 4.8 cases per 1,000 patient-years (33 cases/6,813 pt-years). Both the attack and the incidence rates were significantly higher for lung transplant recipients vs. other transplant recipients: lung 12.8% (24 cases/188 patients) or 40.5 cases/1,000-pt year vs. heart 0.4% (3/686) or 1.4 per 1,000-pt year vs. liver 0.7% (3/439) or 2.1 per 1,000-pt year vs. renal 0.4% (3/733) or 1.2 per 1,000-pt year (P < 0.01). The incidence of IA was highest during the first year after transplantation for all categories, but cases occurred after the first year of transplantation only in lung transplant recipients. The attack rate of IA in lung transplant recipients was significantly lower after institution of routine Aspergillus prophylaxis (4.9% vs. 18.2%, P < 0.05). CONCLUSIONS: The highest incidence and attack rate of invasive aspergillosis among solid organ transplant recipients occurs in lung transplant recipients and supports the routine use of Aspergillus prophylaxis for at least one year after transplantation in this group.

Adult↗
PubMed2001

Hypogammaglobulinemia in lung transplant recipients.

BACKGROUND: Infectious complications continue to represent a significant source of morbidity and mortality in lung transplant recipients. Identifying specific, remediable immune defects is of potential value. After one lung transplant patient with recurrent infections was noted to be severely hypogammaglobulinemic, a screening program for humoral immune defects was instituted. The objectives were to define the prevalence of hypogammaglobulinemia in lung transplant recipients, assess levels of antibody to specific pathogens, and correlate infectious disease outcomes and survival with immunoglobulin levels. METHODS: All lung transplant recipients followed at a single center between October 1996 and June 1999 underwent a posttransplant humoral immune status survey as part of routine posttransplant follow-up. This survey consists of total immunoglobulin levels (IgG, IgM, IgA), IgG subclasses (IgG1-4), and antibody titers to Pneumococcus, diphtheria, and tetanus. Since February 1997, this survey has been incorporated into the pretransplant evaluation as well. Humoral survey results for October 1996 through July 1999 were recorded, and clinical information on major infectious disease outcomes was obtained from chart reviews, discharge summaries, the Cleveland Clinic Unified Transplant Database, and review of all microbiological studies and pathology results for each patient. RESULTS: Of 67 patients with humoral immune surveys drawn posttransplant, 47 (70%) had IgG levels less than 600 mg/dl (normal 717-1410 mg/dl), of which 25 (37%) had IgG levels less than 400 mg/dl ("lowest IgG group") and 22 (33%) had IgG levels between 400 and 600 mg/dl ("moderately low IgG group"). A total of 20 patients (30%) had IgG levels of more than 600 mg/dl ("normal IgG group"). Infections that were significantly more common in the lowest IgG group, and more common in the moderately low IgG group than the normal IgG group, included: number of pneumonias (P=0.0006), bacteremias (P=0.02), total bacterial infections (P=0.002), tissue-invasive cytomegalovirus (P=0.01), invasive aspergillosis (P=0.001), total fungal infections (P=0.001), and total infections (P=0.006). Median hospital days per posttransplant year was significantly different in the three groups (11.0 vs. 7.4 vs. 2.8 days, P=0.0003.) Invasive aspergillosis occurred in 44% of the lowest IgG group, 9% of the moderately low IgG group, and 0% of the normal IgG group (P<0.001). Survival was poorest in the lowest IgG group and intermediate in the moderately low IgG group. IgG subclass deficiencies occurred in a variety of patterns. Hypogammaglobulinemic patients lacked protective responses to Pneumococcus in 14/47 (30%), diphtheria in 15%, and tetanus in 19%. In a group of 48 patients screened pretransplant, 90% had normal immunoglobulin levels. CONCLUSIONS: Hypogammaglobulinemia in lung transplant recipients is more common than has been previously recognized. An IgG level of less than 400 mg/dl identifies a group at extremely high risk of bacterial and fungal infections, tissue-invasive cytomegalovirus, and poorer survival. Immunoglobulin monitoring may offer an opportunity for intensive surveillance, tapering of immunosuppression, and preemptive therapy for infection.

Adolescent↗
PubMed2001

Estimation of left ventricular operating stiffness from Doppler early filling deceleration time in humans.

Shortened early transmitral deceleration times (E(DT)) have been qualitatively associated with increased filling pressure and reduced survival in patients with cardiac disease and increased left ventricular operating stiffness (K(LV)). An equation relating K(LV) quantitatively to E(DT) has previously been described in a canine model but not in humans. During several varying hemodynamic conditions, we studied 18 patients undergoing open-heart surgery. Transesophageal echocardiographic two-dimensional volumes and Doppler flows were combined with high-fidelity left atrial (LA) and left ventricular (LV) pressures to determine K(LV). From digitized Doppler recordings, E(DT) was measured and compared against changes in LV and LA diastolic volumes and pressures. E(DT) (180 +/- 39 ms) was inversely associated with LV end-diastolic pressures (r = -0.56, P = 0.004) and net atrioventricular stiffness (r = -0.55, P = 0.006) but had its strongest association with K(LV) (r = -0.81, P < 0.001). K(LV) was predicted assuming a nonrestrictive orifice (K(nonrest)) from E(DT) as K(nonrest) = (0.07/E(DT))(2) with K(LV) = 1.01 K(nonrest) - 0.02; r = 0.86, P < 0.001, DeltaK (K(nonrest) - K(LV)) = 0.02 +/- 0.06 mm Hg/ml. In adults with cardiac disease, E(DT) provides an accurate estimate of LV operating stiffness and supports its application as a practical noninvasive index in the evaluation of diastolic function.

Aged↗
PubMed2000

The impact of routine mycophenolate mofetil drug monitoring on the treatment of cardiac allograft rejection.

INTRODUCTION: Mycophenolate mofetil (MMF) is a unique immunosupressive agent that has been shown to be efficacious in the treatment of cardiac allograft rejection. The utility of therapeutic drug monitoring on rejection prophylaxis and treatment is inconclusive. This study was undertaken to evaluate the incidence of rejection in relation to MMF trough level following heart transplantation. METHODS: Between May 1998 and February 1999, we retrospectively analyzed the clinical outcome of 215 heart transplant patients who had routine monitoring of MMF trough level at the time of scheduled endomyocardial biopsy. Patients were divided into three groups according to the time interval post transplant, and were evaluated in relation to the MMF trough level. Group I, 104 patients within 6 months of transplant; Group II, 90 patients, 6-12 months post transplant; and Group III, 71 patients beyond one year of transplant. Fifty patients had samples in more than one group. Rejection was defined as Grade > or = 3A based on ISHLT criteria. Mean follow-up period was 179+/-52 days. RESULTS: A significantly decreased incidence of rejection was noted in the samples with MMF trough level > or = mg/l compared to those with less than 2 mg/l inpatients evaluated within the first year of transplant (Group I: 8.8% vs. 14.9%, Group II: 4.2% vs. 11.3%, both P=0.05). In the presence of therapeutic cyclosporine (CSA) or tacrolimus (FK) blood levels, the incidence of rejection decreased significantly when MMF trough level was > or = 2 mg/l compared to samples with MMF trough level <2 mg/l (3.6% vs. 14.4%, P=0.005). No significant difference was noted in the presence of subtherapeutic CSA or FK levels (15.4% vs. 13.9%, P=NS). CONCLUSIONS: Monitoring of MMF trough levels may play a role in the management of cardiac transplant recipients during the first year post transplant.

Adult↗
PubMed2000

Does coronary angiography before emergency aortic surgery affect in-hospital mortality?

OBJECTIVES: To study the relationship between coronary angiography and in-hospital mortality in patients undergoing emergency surgery of the aorta without a history of coronary revascularization or coronary angiography before the onset of symptoms. BACKGROUND: In the setting of acute ascending aortic dissection warranting emergency aortic repair, coronary angiography has been considered to be desirable, if not essential. The benefits of defining coronary anatomy have to be weighed against the risks of additional delay before surgical intervention. METHODS: Retrospective analysis of patient charts and the Cardiovascular Information Registry (CVIR) at the Cleveland Clinic Foundation. RESULTS: We studied 122 patients who underwent emergency surgery of the aorta between January 1982 and December 1997. Overall, in-hospital mortality was 18.0%, and there was no significant difference between those who had coronary angiography on the day of surgery compared with those who had not (No: 16%, n = 81 vs. Yes: 22%, n = 41, p = 0.46). Multivariate analysis revealed that a history of myocardial infarction (MI) was the only predictor of in-hospital mortality (relative risk: 4.98 95% confidence interval: 1.48-16.75, p = 0.009); however, coronary angiography had no impact on in-hospital mortality in patients with a history of MI. Furthermore, coronary angiography did not significantly affect the incidence of coronary artery bypass grafting (CABG) during aortic surgery (17% vs. 25%, Yes vs. No). Operative reports revealed that 74% of all CABG procedures were performed because of coronary dissection, and not coronary artery disease. CONCLUSIONS: These data indicate that determination of coronary anatomy may not impact on survival in patients undergoing emergency surgery of the aorta and support the concept that once diagnosed, patients should proceed as quickly as possible to surgery.

Acute Disease↗
PubMed2000

Significant post-transplant hypogammaglobulinemia in six heart transplant recipients: an emerging clinical phenomenon?

BACKGROUND: The recent development of powerful agents such as mycophenolate mofetil and tacrolimus has altered current regimens for the prevention and treatment of allograft rejection. Questions have been raised about these newer regimens in terms of susceptibility to opportunistic infections and effects on host defenses. Severe hypogammaglobulinemia has been infrequently described in solid organ transplant recipients, but has been recently noted in six heart transplant recipients at one center, of whom five were receiving a combination of tacrolimus, mycophenolate mofetil, and prednisone. METHODS: Case summaries of six recent heart transplant recipients with total immunoglobulin G (IgG) levels of less than 310 mg/dl, five of whom had cytomegalovirus (CMV) infection and three of whom had multiple infections including Nocardia, invasive Trichophyton, and Acinetobacter bacteremia. Previous literature was reviewed with the aid of a Medline search using the search terms hypogammaglobulinemia; kidney, liver, heart, lung, and organ transplantation; mycophenolate mofetil; tacrolimus; cyclosporine; azathioprine; and nocardiosis. RESULTS: We here report six cardiac transplant recipients seen over a period of one year who were found to have immunoglobulin G levels of 310 mg/dl or below (normal: 717-1400 mg/dl). The first five patients were diagnosed because of evaluation for infections; the sixth, who was asymptomatic with an IgG level of 175, was found during screening for hypogammaglobulinemia instituted as a result of these first five patients. All six patients had received steroid pulses for rejection; all received mycophenolate mofetil; and 5/6 had been switched from cyclosporine to tacrolimus because of steroid-resistant rejection. Transient neutropenia (absolute neutrophil count less than 1000) was observed in 2/6; 3/6 had received OKT3 therapy for refractory rejection. These six patients were treated with a combination of antimicrobials, immunoglobulin replacement, and decrease in immunosuppressive therapy. CONCLUSION: The finding of unexpected hypogammaglobulinemia and concomitant infectious complications in six heart transplant recipients highlights a possible complication in a subset of patients receiving newer immunosuppressive agents. A larger prospective study is underway to determine risk factors for development of post-transplant hypogammaglobulinemia and to assess pre-transplant immune status of these recipients. Monitoring of immunoglobulin levels in high-risk patients receiving intensified immunosuppressive therapy for rejection may help to prevent infectious complications.

Acinetobacter Infections↗
PubMed2000

Pulmonary vasoregulation by endothelin in conscious dogs after left lung transplantation.

We tested the hypothesis that regulation of the pulmonary circulation by endogenous endothelin (ET) during normoxia and hypoxia was altered in conscious dogs 1 mo after left lung autotransplantation (LLA). Sham-operated control and post-LLA dogs were chronically instrumented to measure the left pulmonary vascular pressure-flow (LP-Q) relationship. LP-Q plots were generated on separate days during normoxia and hypoxia (arterial PO(2) approximately 50 Torr) in the intact condition, after selective ET(A)-receptor inhibition (BQ-485), and after combined ET(A+B)-receptor inhibition (bosentan). Although LLA resulted in a chronic increase in pulmonary vascular resistance, the ET-receptor antagonists had no effect on the LP-Q relationship during normoxia in either group. The magnitude of hypoxic pulmonary vasoconstriction (HPV) was flow dependent in both groups, and the HPV response was potentiated post-LLA compared with control. ET(A)-receptor inhibition attenuated the HPV response to the same extent in both groups. ET(A+B)-receptor inhibition attenuated the HPV response to a greater extent than did ET(A)-receptor inhibition alone, and this effect was greater post-LLA compared with control. Plasma ET-1 concentration only increased during hypoxia in the LLA group. These results indicate that ET does not regulate the baseline LP-Q relationship in either group. Both ET(A)- and ET(B)-receptor activation mediate a component of HPV in conscious dogs, and the vasoconstrictor influence of ET(B)-receptor activation is enhanced post-LLA.

Animals↗
PubMed1999

Outcome of de novo hepatitis C virus infection in heart transplant recipients.

The outcome of de novo hepatitis C virus (HCV) infection in heart transplant recipients of HCV-antibody positive organs is not known. The aim of the study was to determine the short-term outcome of de novo HCV infection in recipients of HCV-positive donor organs. HCV-antibody negative recipients of HCV-antibody positive hearts were identified from January 1, 1991 to February 28, 1998. Control patients matched for year of transplantation were also identified. Twenty-eight patients (22 males, mean age of 56 +/- 11 SD) received hearts from HCV-antibody-positive donors. The control group was similar to the patients in all clinical and demographic aspects. Twenty-three patients had detectable viremia by reverse-transcription polymerase chain reaction (RT-PCR). Of these 23 patients with de novo HCV infection, 7 (30%) developed HCV-related liver disease. Three patients (13%) had chronic hepatitis and 4 patients (17%) developed severe acute cholestatic hepatitis (ACH). Mycophenolate mofetil (MMF) use (P =.04) and high viral load at onset of acute liver disease (P =.02) were associated with ACH. Overall survival was similar between patients with de novo HCV infection and controls (P =.20). Development of ACH (P =.02) and MMF use (P =.0009) were associated with decreased survival in patients with de novo HCV infection. The present study showed that survival of patients with de novo HCV infection was similar to a matched control group. HCV-related severe ACH is associated with a poor short-term outcome in patients with de novo HCV infection. MMF use may be associated with a higher incidence of HCV-related severe ACH and a poor short-term outcome.

Actuarial Analysis↗
PubMed1999

Transesophageal echocardiography diagnosis of intramural hematoma of the ascending aorta: A word of caution.

The diagnosis of intramural hematoma by echocardiography classically requires the presence of an echolucent, crescentic region in the wall of the aorta. Recently we have encountered 2 patients in whom intramural hematoma was characterized only by thickening of the aortic wall, which was circumferential in one patient, thus making the diagnosis difficult to distinguish from common atherosclerotic thickening of the aorta. In one case, computed tomography showed more clearly the abnormal tissue signature of the intramural blood. In summary, absence of an echolucent zone does not exclude the diagnosis of intramural hematoma. Alternative imaging procedures such as computed tomography and magnetic resonance imaging may enhance the diagnostic accuracy.

Aged↗
PubMed1991

Alveolar and lung liquid clearance in anesthetized rabbits.

Alveolar and lung liquid clearance were studied over 8 h in intact anesthetized ventilated rabbits by instillation of either isosmolar Ringer lactate (2 ml/kg) or autologous plasma (2 or 3 ml/kg) into one lower lobe. The half time for lung liquid clearance of the isosmolar Ringer lactate was 3.3 h and that for plasma clearance was 6 h. In the plasma experiments, the alveolar protein concentration after 1 h was 5.2 +/- 0.8 g/dl, which was significantly greater than the initial instilled protein concentration of 4.3 +/- 0.7 g/dl (P less than 0.05). Thus alveolar protein concentration increased by 21 +/- 12% over 1 h, which matched clearance from the entire lung of 19 +/- 11% of the instilled volume. Overall the rate of alveolar and lung liquid clearance in rabbits was significantly faster than in prior studies in dogs and sheep. The fast alveolar liquid clearance rate in rabbits was not due to higher endogenous catecholamine release, because intravenous and alveolar (5 x 10(-5) M) propranolol did not slow the clearance. Also, beta-adrenergic therapy with alveolar terbutaline (10(-5) or 10(-4) M) did not increase the alveolar or lung liquid clearance rates. Phloridzin (10(-3) M) did not slow alveolar liquid clearance. However, amiloride (10(-4) M) inhibited 75% of the basal alveolar liquid clearance in rabbits, thus providing evidence that alveolar liquid clearance in rabbits depends primarily on sodium-dependent transport. This rabbit study provides further evidence for important species differences in the basal rates of alveolar liquid and solute clearance as well as the response to beta-adrenergic agonists and ion transport inhibitors.

Amiloride↗
PubMed1989

Blunt abdominal trauma.

Blunt abdominal trauma results in potentially life-threatening injuries that require organized rapid evaluation and treatment. Resuscitation of hemodynamically unstable patients should be completed in the operating room if retroperitoneal hemorrhage is not strongly suspected. DPL and abdominal CT scans are methods of studying the injured abdomen, and each has advantages and disadvantages. The clinician must choose the appropriate study based on the clinical question raised by each patient. Repeated frequent physical examinations and serial laboratory tests are essential to exclude a missed injury. Deterioration of hemodynamic status or abdominal examination are indications for urgent laparotomy regardless of the initial diagnostic impressions.

Abdominal Injuries↗