Effects of mycophenolate sodium on mucociliary clearance using a bronchial section and anastomosis rodent model

OBJECTIVE:

To study the effects of mycophenolate sodium on mucociliary clearance.

INTRODUCTION:

Mycophenolate is one of the most commonly used immunosuppressive drugs in lung transplantation. Although its pharmacokinetic properties are well defined, its side effects on mucociliary clearance have not yet been studied.

METHODS:

Sixty rats were subjected to left bronchial section and anastomosis. The right bronchus was used as a control. After surgery, the rats were assigned to two groups based on whether they received saline solution (n = 30) or mycophenolate sodium (n = 30). After 7, 15, or 30 days of treatment, 10 animals from each group were sacrificed, and in vitro mucus transportability, in situ mucociliary transport velocity and ciliary beat frequency were measured.

RESULTS:

The analysis of mucus transportability revealed that neither mycophenolate nor bronchial section altered any transportability related property for up to 30 days of treatment after surgery (p>0.05). With regard to ciliary beat frequency, the operated left bronchi from the mycophenolate group showed a significant decrease on post-surgical day 30 (p = 0.003). In addition, we found a significant reduction in the in situ mucociliary transport velocity in the mycophenolate-treated group (p = 0.0001).

DISCUSSION:

These data add important information regarding mucociliary clearance dysfunction following mycophenolate therapy and suggest that mycophenolate might contribute to the high incidence of respiratory tract infections in lung transplant patients. Further studies are needed to investigate the combined action of mycophenolate with other immunosuppressive drugs and to establish methods to protect and recover mucociliary clearance, an important airway defense mechanism.     

Surgical Myocardial Revascularization of Patients with Ischemic Cardiomyopathy and Severe Left Ventricular Disfunction

OBJECTIVE:

To determine long-term survival, identify preoperative factors predictive of a favorable outcome, and assess functional improvement after coronary artery bypass grafting in patients with advanced left ventricular dysfunction.

METHODS:

Between 1995 and 2001, 244 patients who underwent coronary artery bypass grafting and had a preoperative left ventricular ejection fraction less than or equal to 35% were included. left ventricular ejection fraction was determined by uniplanar or biplanar ventriculography during left heart catheterization. Indication for surgery was predominance of tissue viability. Functional improvement was evaluated through echocardiography and gated scintigraphy at exercise/rest. Survival was determined by Kaplan-Meier analysis.

RESULTS:

Mean left ventricular ejection fraction was 29±4% (ranged from 9% to 35%). An average of 3.01 coronary bypass grafts per patient were performed. In-hospital mortality was 3.7% (9 patients). The 4-year survival rate was 89.7%. Multivariate correlates of favorable short- and long-term outcome were preoperative New York Heart Association Funcional classification for congestive heart failure class I/II, lower PAsP, higher left ventricular ejection fraction and gated left ventricular ejection fraction Ex/Rest ratio >5%. Left ventricular ejection fraction rise from 32±5% to 39±5%, p <0.001. Gated left ventricular ejection fraction at exercise/rest increased markedly after surgery: from 27±8%/23±7% to 37±5%/31±6%, p <0.001.

CONCLUSIONS:

In selected patients with severe ischemic left ventricular dysfunction and predominance of tissue viability, coronary artery bypass grafting may be capable of implement preoperative clinical/functional parameters in predicting outcome as left ventricular ejection fraction and gated left ventricular ejection fraction at exercise/rest.     

Hybrid Management for Hypoplastic Left Heart Syndrome

Initial surgical reconstruction for hypoplastic left heart syndrome (HLHS) is associated with satisfactory outcomes only in a few referral centers. Moreover, there is a persistent high-risk period for sudden death while the patient waits for the next surgical procedure. The development of a less invasive approach, so-called “hybrid,” postponing a major surgery outside the neonatal period, might reduce the immediate and late surgical burden on these patients. This is a retrospective study of a contemporary series of patients with HLHS seen in two separate institutions. Patients with HLHS or its variants who underwent a “hybrid” management were included in the study. Data are described as the mean and standard deviation or absolute numbers and percentage, as appropriate. From January 2004 to June 2006, 15 patients (10 male; 5 ± 3.8 days old and 2.9 ± 0.5 kg) were included in the study. Ten had both mitral and aortic atresia; the ascending aorta and atrial septal defect measured 2.5 ± 1.4 and 4.9 ± 1.2 mm, respectively. There were six hospital survivors after stage I (mortality rate 60%). During the interstage period, all but one patient needed additional procedures. One patient died of bacterial meningitis 4 months after stage I. Four patients were submitted to stage II operation at 6.6 ± 0.5 months of age and one is waiting for the operation. All four required early reinterventions for pulmonary artery stenosis. Only one was discharged home and was not yet submitted to the third stage. The hybrid approach for HLHS was associated with poor results in this early experience from two independent institutions in a developing country. This might have been related to infrastructure and technical problems, as well as our own learning curve. Institutions working under the same conditions might face similar problems during their initial experience.     

The Role of Invasive Therapies in Elderly Patients with Acute Myocardial Infarction

INTRODUCTION:

In elderly patients with acute myocardial infarction, very little is known about the role of surgical myocardial revascularization and percutaneous coronary intervention (invasive therapies - IT), especially in the context of long-term outcomes after hospital discharge.

METHODS:

We analyzed 1588 patients with MI who had been included prospectively in a databank and followed for up to 7.5 years. In this population, 548 patients were ≥70 years old (elderly group - EG), and 1040 were <70 years of age (younger group - YG); 1088 underwent IT during hospitalization, and the remaining 500 were treated medically (conservative therapy - CT). Patients were monitored either by visit or by phone at least once a year. A standard questionnaire was administered to all patients. The impact of IT was analyzed with both non-adjusted and adjusted models.

RESULTS:

By the end of the follow-up period, the survival rates for the IT and CT groups were, respectively, 71.9% versus 47.2% in the global population (hazard ratio=0.55, P<0.001), 81.5% versus 66.6% in the YG (hazard ratio=0.68, P=0.018) and 48.8% versus 20.3% in the EG (hazard ratio=0.58, P<0.001). In the adjusted models, the hazard ratios were 0.62 (P<0.001) in the global population, 0.74 in the YG (P=0.073) and 0.64 (P=0.001) in the EG.

CONCLUSION:

Long-term follow-up of patients with myocardial infarction revealed that IT during the in-hospital phase was at least as effective in elderly patients as in younger patients.     

In-111-labeled white blood cell uptake in noninfected closed fracture in humans: prospective study

Since indium-111 white blood cell (In-111 WBC) scintigraphy is often used to evaluate for osteomyelitis in bone fractures, it is important to know if noninfected fractures have In-111 WBC uptake. Twenty-seven noninfected closed fracture sites in 19 patients were prospectively evaluated with technetium-99m methylene diphosphonate bone scintigraphy and In-111 WBC scintigraphy. In-111 WBC uptake was present in 41% of the 27 sites. In the 11 positive sites, the In-111 WBC uptake was 1+ (definite but minimal) in 55%, 2+ (moderate) in 36%, and 3+ (marked) in 9%. The visual intensity of the radioactive uptake on In-111 WBC scintigrams relative to that on bone scintigrams was less in 82%, equal in 9%, and greater in 9%. The visual size of the area of uptake on In-111 WBC scintigrams and bone scintigrams was smaller in 36%, equal in 55%, and greater in 9%. Factors that may help distinction of In-111 WBC uptake due to fracture alone from infection associated with fracture are discussed.