Tacrolimus-Eluting Suture Inhibits Neointimal Hyperplasia: An Experimental In Vivo Study in Rats.

OBJECTIVE/BACKGROUND: Neointimal hyperplasia (NIH) remains one of the leading causes of graft failure after vascular anastomoses. Cytotoxic drugs, such as rapamycin and tacrolimus, have been shown to inhibit the development of NIH. In this study, the aim was to test the impact of a sustained releasing tacrolimus-chitosan-eluting suture on the development of NIH in a rat model. METHODS: After tacrolimus-chitosan coating of a 7/0 polyvinylidene difluoride (PVDF) Trofilen® suture, the tacrolimus concentration on the coated suture and in vitro release trials were performed spectrophotometrically. Twelve Wistar rats were included. After midline laparotomy, a 7-8 mm longitudinal aortotomy in the infrarenal aorta was made and then closed by a bare 7/0 PVDF (group C, n = 6) and a 7/0 tacrolimus-chitosan coated PVDF suture (0.65 µg/cm tacrolimus [0.9 wt%] + 1.82 µg/cm chitosan [2.28 wt%]) (group T, n = 6). After 1 month, rats were sacrificed and aortotomy sites were examined histologically by ratio of intimal area (including neointima) and immunohistochemically by α-smooth muscle actin (ASMA) and proliferating cell nuclear antigen (PCNA) immunostaining. The PCNA positive cells were indexed to total cell number and expressed as percentage. RESULTS: In vitro tacrolimus release tests for a 7/0 tacrolimus-chitosan coated PVDF suture were confirmed for 1 month without an initial burst release. Endothelialisation over the aortotomy line occurred in both groups. The area of neointima was significantly reduced in group T compared with group C (ratio 0.22 ± 0.12 vs. 0.42 ± 0.11; p = .017) 1 month post-operatively. Likewise, the percentage of PCNA immunostaining significantly decreased in group C compared with group T (3.83 ± 2.85% vs. 11.17 ± 7.78%; p = .026). The cells constituting NIH were positive for ASMA immunostaining. CONCLUSIONS: Tacrolimus-chitosan-eluting suture is shown to be an effective way to reduce NIH without interfering with normal endothelialisation.

Results of pericardiectomy for constrictive pericarditis : Single-center experience.

BACKGROUND: We evaluated our early and late outcomes after pericardiectomy in patients with constrictive pericarditis (CP). PATIENTS AND METHODS: We retrospectively reviewed 31 patients who underwent pericardiectomy for CP from 1997 to 2015. Their mean age was 49.2 ± 18.5 years and 74.2 % of them were male. The vast majority had severe functional impairment (NYHA class III-IV) with a mean duration of symptoms of 14.2 ± 10.1 months. RESULTS: Early mortality was 9.7 %: n = 3; multiorgan failure (MOF) in 1, respiratory failure in 1, and left heart failure in 1. Preoperative systolic pulmonary artery pressure over 60 mmHg (p = 0.038, odds ratio [OR] = 0.12) and postoperative low cardiac output syndrome (p = 0.005, OR = 13.5) were significant predictors of early mortality in univariate analysis. Mean follow-up time was 57.8 ± 61.9 months (4-216 months). Late mortality was 6.8 % (2/28 patients) and the cause was MOF secondary to end-stage right heart failure. In Kaplan-Meier analyses, actuarial (including early mortality) and event-free survival rates were 83.9 and 51.1 % at 216 months, respectively. At the end of follow-up, the majority of patients (23/26, 92.9 %) were in good functional status (NYHA class I-II). There were fewer patients under diuretic therapy in the postoperative than in the preoperative period; however, the difference was not statistically significant (12/31 vs. 4/26, p = 0.76). There was no significant difference between the preoperative and follow-up tricuspid annular plane systolic excursion values (15.5 ± 2.2 and 16.6 ± 2.2 mm, respectively, p = 0.088). Left ventricular systolic function was preserved in all patients postoperatively. CONCLUSION: Although early mortality after pericardiectomy remains high, the procedure provides significant improvement in functional status in the long term.

Methylene blue decreases ischemia-reperfusion (I/R)-induced spinal cord injury: an in vivo study in an I/R rabbit model.

OBJECTIVES: To evaluate the effects of intravenous methylene blue (MB) administration on ischemia-reperfusion (I/R) injury of the spinal cord (SC). METHODS: 16 rabbits were randomly assigned either to group M (n = 8; receiving MB, intervention group) or group C (n = 8; control group) and underwent a 30-min period of SC ischemia by clamping the abdominal aorta between the left renal artery and the aortic bifurcation. 15 min before clamping, rabbits received either intravenous MB (10 mg/kg; group M) or normal saline (group C). The two groups were compared 24 h postoperatively both histologically and for neurological function, using a Tarlov score. Measurements to determine levels of malondialdehyde (MDA) and glutathione (GSH) in the SC tissue were also performed. RESULTS: Neurological impairment and spinal tissue MDA levels were significantly lower in animals treated with MB (p < 0.001). In contrast, spinal GSH levels were significantly higher in group M (p < 0.001). Histological examination revealed that the integrity of the SC was better preserved in the MB group, whereas cords from the control group exhibited evidence of acute neuronal injury. CONCLUSIONS: The prophylactic use of MB reduces neurological injury and improves clinical outcomes in the rabbit SC I/R model. These effects are probably mediated by the drug's antioxidant properties.

Surgical drainage of late cardiac tamponade following open heart surgery.

BACKGROUND: There are few reports on postoperative late cardiac tamponade with surgical therapy in the literature. METHODS: Hospital records of 87 patients with postoperative late cardiac tamponade who had undergone cardiac surgery between January 1999 and December 2003 were evaluated retrospectively. RESULTS: Out of 8400 patients who had undergone cardiac surgery, 87 patients (1 %) had postoperative late cardiac tamponade. The incidence was 0.1 % for patients with coronary artery bypass grafting and 3.4 % for those with heart valve replacement ( p < 0.01). Subxiphoid midline incision was carried out in 67 patients (77 %). Conversion to re-sternotomy was required in 8 patients due to either ineffective drainage (5 patients, 7.5 %) or laceration and bleeding (3 patients, 4.5 %). Re-sternotomy was undertaken in 20 patients with no complication. Early death occurred in 3 patients with subxiphoid drainage (3.5 %), two of which were related to bleeding. Out of 84 patients who survived, 10 patients had recurrent cardiac tamponade, 5 of which required surgical drainage (6 %). CONCLUSIONS: Bleeding due to dense adhesions between the epicardium and the sternum may be encountered during subxiphoid drainage for postoperative late cardiac tamponade and lead to a 3 % mortality rate.

Is there a role of angiotensin-converting enzyme gene polymorphism in the failure of arteriovenous femoral shunts for hemodialysis?

In humans, thrombosis and neointimal hyperplasia are the major factors responsible for prosthetic graft occlusion. Previous studies suggest that the renin-angiotensin system is one of the key enzymes in the vascular system and has been implicated in the pathogenesis of thrombosis and neointimal hyperplasia. We conducted a case-control study to determine the frequency of the different angiotensin-converting enzyme (ACE) genotypes among the patients who had PTFE graft implantation for hemodialysis access. Between 1997 and 1999, 30 graft implantations were performed. Twelve individuals (40%) developed thrombotic complications, 8 of the 12 patients had ACE ID polymorphism, and 2 patients had DD and 2 patients had II polymorphism. The ID polymorphism was significantly more frequent in the thrombosed arteriovenous (A-V) grafts than in nonthrombosed A-V grafts (chi2 = 7.57 and p = 0.02). Overall, the frequency of the D and I alleles was 66.6 and 33.3%, respectively. In conclusion, ID polymorphism of the ACE gene plays an important role in the pathogenesis of vascular access thrombosis in subjects undergoing hemodialysis for chronic renal failure.

Idiopathic main pulmonary artery aneurysm.

Main pulmonary artery aneurysms with no underlying pathology are very rare, and the role of surgery in this entity is not well defined. We report our experience of one case.

Right iliac vein agenesis, varicosities, and widespread hemangiomas: report of a rare case.

We present a probable variant of the Klippel-Trénaunay syndrome with the clinical features of capillary hemangiomas, varicosities, and agenesis of the right iliac venous system, but without limb hypertrophy. To our knowledge, this is the 1st such case reported in the medical literature.

Tricuspid valve myxoma in a pediatric patient: 10-year follow-up after resection.

Cardiac myxomas are rarely encountered in pediatric patients. Tricuspid valve involvement in these cases is even more exceptional. We report the case of a 5-year-old girl operated on successfully 10 years ago for a tricuspid valve myxoma who continues to be asymptomatic and had an event free outcome.

Repair of partial atrioventricular septal defect in children less than five years of age: late results.

BACKGROUND: Presently, surgical correction of partial atrioventricular septal defects is an extremely viable option giving good results. An aggressive approach toward operating on these patients at an early age may be warranted given the otherwise unfavorable natural history. METHODS: A retrospective study was done in 38 consecutive patients from 3 to 58 months of age, who underwent correction between 1981 and 1997. Preoperatively, moderate to severe mitral regurgitation was present in 45% of the patients. Congestive cardiac failure was noted in 41% of the cases. Closure of the left atrioventricular valve cleft was performed in 92% of the cases. A need for mitral annuloplasty was felt in 28% of the cases. Majority of the ostium primum defects in our series were closed by a pericardial patch. RESULTS: The early, 30 day mortality was 7.9%. A significantly low incidence of late mitral regurgitation (0.9%) was noted on a follow-up extending up to 14 years. There was only one reoperation during late follow-up. On their last follow-up, 87% of the patients are asymptomatic. CONCLUSION: An aggressive approach toward operating at an early age on children with this malformation is safe, effective, and yields excellent long term results.

Micromultiplane transesophageal echocardiographic probe for intraoperative study of congenital heart disease repair in neonates, infants, children, and adults.

This study reports the development of a micromultiplane 8.2-mm transesophageal echocardiographic probe. The probe is applicable to newborn infants and can deliver diagnostic images in adults.

Discrete subaortic stenosis: an acquired heart disease.

OBJECTIVE: To determine the anatomic variables in the left ventricular outflow tract in patients with subaortic stenosis. METHODS: Between 1982 and 1996, 36 patients were operated on with the 'discrete' form of subaortic stenosis (DSS). The mean time of follow up was 7.4 years with a range of 4 months-14 years. There were 25 male and 11 female patients. Mean age at operation was 7.1 years with a range of 9 months-47 years. RESULTS: At the time of surgery, the mitral valve apparatus and interventricular septum were found to be rotated 60-90 degrees in a counterclockwise fashion with anterior displacement into the left ventricular outflow tract in 30 (83%) patients. Subaortic ridge resection with a deep septal myectomy was performed in 32 patients and the remaining four patients had subaortic ridge resection alone. The reoperation free rate at 5 and 10 years were 74+/-9% and 60+/-12%, respectively. Reoperations for recurrent disease were performed in 10 (27.7%) patients. No operative or late follow up deaths were encountered. CONCLUSION: We conclude that DSS is an acquired disease due to a pre-existing anatomic alteration in the mitral valve apparatus and interventricular septum. In addition, recurrence rates are high and physicians should not be mislead by the benign nomenclature its name implies.

Surgery for coarctation of the aorta in infants younger than 3 months: end-to-end repair versus subclavian flap angioplasty: is either operation better?

OBJECTIVE: Recurrent coarctation is a complication which is seen at a consistent rate following all types of repair for coarctation of the aorta. Particularly disappointing late results are reported in younger infants, under 3 months of age. This retrospective analysis was undertaken to compare the outcomes on late follow-up between subclavian flap angioplasty and resection and end-to-end repair, in this age group. METHODS: Over a 12-year period, between 1982 and 1994, 86 infants under 3 months of age underwent surgical repair of coarctation (39 resections and end-to-end repair, and 47 subclavian flap angioplasty procedures). Operative mortality was not significantly different (P = 0.6) between resection and end-to-end repair (5.1%) and subclavian flap angioplasty (8.5%). All operative deaths (six patients) were in infants with associated ventricular septal defects. The mean follow-up for all patients was 7.95 years +/- 4.10 (range 0-14.5 years). The 5-year survival for resection and end-to-end repair was 87 +/- 5%, compared to 75 +/- 7% for subclavian flap angioplasty (P = 0.2). RESULTS: Recurrent coarctation occurred in nine patients who needed reoperation. The reoperation-free rates at both 5 and 10 years for resection and end-to-end anastomosis, and subclavian flap repair were 86 +/- 6% and 90 +/- 5%, respectively. The recurrence in the resection and end-to-end anastomosis group were due to constrictive scarring at the anastomosis, whereas periductal tissue and growth of posterior aortic ridge caused recurrence in the subclavian flap angioplasty group. There were no deaths during reoperation for recurrence. CONCLUSIONS: Both procedures are extremely effective for coarctation repair in young infants and run a similar risk of recurrence, which are due to completely different mechanisms. The surgeon's expertise is the major determinant of outcome.

Squamous and basal cell carcinoma in heart transplant recipients.

BACKGROUND: Cutaneous malignancies are frequent in organ transplant recipients. We retrospectively reviewed a large series of heart transplant recipients and report on the prevalence and risk factors for development of cutaneous squamous and basal cell carcinoma. METHODS: Between Dec. 4, 1985, and Dec. 27, 1996, 299 heart transplantations were performed at the Oregon Health Sciences University. Heart transplant recipients with more than 6 months survival or follow-up were investigated for squamous and basal cell carcinoma (n = 248). RESULTS: Forty-one patients (17%) were found to have 192 squamous or basal cell carcinomas. Squamous cell carcinoma was the predominate skin malignancy, constituting 172 (90%) of the lesions. The mean number of skin malignancies per patient was 4.7 +/- 0.81 (range 125). Patients with development of a skin malignancy were 8 years older on average, with a male-to-female ratio of 19.5:1. The predominant skin type and eye color were fair (59%) and blue (59%), respectively. Cumulative risk, based on actuarial survival analysis for development of a squamous or basal cell carcinoma at 1 year, was 3% and increased to 21% and 35% at 5 and 10 years, respectively. In addition, cumulative risk increased in patients who received treatment with OKT3. CONCLUSION: Cumulative risk of development of a skin malignancy increased with time and use of OKT3. Additional patient risk factors included older age, male sex, fair skin, and blue eyes.

Diagnostic accuracy and role of intraoperative biplane transesophageal echocardiography in pediatric patients with left ventricle outflow tract lesions.

OBJECTIVES: To define the lesion-specific role of biplane transesophageal echocardiography in children with left ventricular outflow tract obstructive lesions, the diagnostic accuracy of transthoracic and transesophageal images were compared, and the impact of transesophageal echocardiography on perioperative management was evaluated. BACKGROUND: The reported high postoperative recurrence of left ventricular outflow tract obstructive lesion can be due to its incomplete surgical relief. A full preoperative definition of the lesions would aid in better surgical outcome. The complexity and spectrum of such lesions provide opportunity to evaluate the role of a recently available biplane transesophageal pediatric probe in its diagnosis and surgical management. METHODS: In 16 consecutive patients (11 male patients) with left ventricular outflow tract obstructive lesions and with a mean age of 7.9 +/- 5.7 years (range 0.25 to 20.0 years) and a mean weight of 29 +/- 19 kg (range 4 to 66 kg), the morphologic and hemodynamic findings of standard preoperative transthoracic and intraoperative biplane transesophageal echocardiography were compared with surgical and cardiac catheterization findings (in seven patients) for the diagnostic accuracy and impact on the surgical management of the lesions. RESULTS: Based on the levels of agreement, transesophageal echocardiography demonstrated higher diagnostic sensitivity (chi-squared analysis = 13.4 < 0.001) to the presence and extent of associated lesions (septal hypertrophy, multiple fibromuscular insertions, involvement of aortic and mitral valves not revealed by transthoracic imaging) and trend toward higher sensitivity (Fisher's exact p = 0.17) to primary morphologic diagnoses (abnormal chordal attachments, prolapsed aortic cusp, and tunnel-like outflow tract obstructive lesions missed by transthoracic imaging). As a result of these factors, intraoperative transesophageal imaging changed the surgical plan in 25% of the patients and modified it in an additional 25% of the patients. CONCLUSIONS: Transesophageal echocardiography can be a reliable diagnostic tool and has an important role in the surgical management of left ventricular outflow tract lesions in children.

Aortoventriculoplasty after a prior posterior root enlargement (Manougian): case report.

A patient with congenital bicuspid aortic stenosis had an open commissurotomy followed 3 years later by a Manougian's operation along with an aortic valve replacement. Nine years later, due to residual aortic stenosis, a Konno's anterior root enlarging procedure with an aortic valve replacement was successfully done. Good relief of aortic and subaortic stenosis and the absence of significant gradient across the left ventricular outflow tract led us to believe that successful and effective relief could be obtained by adding a Konno-type of enlargement to a previously performed posterior enlargement procedure.

Sweet's syndrome and associated sarcoidosis--a rare clinical case.

Sweet's syndrome is frequently idiopathic; however, it has been associated with malignancy in up to 20% of reported cases. We report a case of concurrent presentation of Sweet's syndrome with sarcoidosis. Although this association has been infrequently described we feel that this could be an alternative diagnosis in patients with Sweet's syndrome who present with mediastinal lymphadenopathy with or without erythema nodosum. The relevant literature on this subject is reviewed.

FK506-induced fulminant leukoencephalopathy after single-lung transplantation.

FK506 is being used increasingly to prevent rejection after organ transplantation. Its use is associated with a wide spectrum of neurotoxicity, which has been described after most solid organ transplantations, but reports after lung transplantation are extremely rare. This is a report of the pathologic correlation of the clinical and radiologic features of delayed FK506-induced fulminant leukoencephalopathy after single-lung transplantation. The patient presented with neurologic symptoms that progressed to seizure activity. Neuroimaging showed diffuse changes in the brain, and results of a brain biopsy were consistent with leukoencephalopathy with microglial and astrocytic activation. The patient had a remarkable improvement in clinical status after discontinuation of FK506 administration, with resolution of the changes seen on neuroimaging.

Temporary stenting of the sternum after difficult cardiac operations.

Stenting the sternum may be essential to keep the sternal edges apart and optimize the hemodynamics in some patients, after cardiac operations. We have devised an effective stent that can be prepared very quickly from the equipment available in the operating room.

Usefulness of transesophageal imaging of flow convergence region in the operating room for evaluating isolated patent ductus arteriosus.

Transesophageal echocardiography (TEE) was performed in 21 patients with isolated patent ductus arteriosus (PDA) with a color Doppler flow convergence method during surgical closure of the ductus. Evaluation of PDA by TEE with the flow convergence method may provide valuable information during surgery and/or thorascopic ductus clipping.

Glucose management in the infant under six kilograms.

A retrospective, nonrandomized study of blood glucose levels in very young children under 6 kg was undertaken. Each patient underwent the repair of complex congenital heart defects using hypothermia and nonpulsatile cardiopulmonary bypass (CPB). Hyperglycaemia may cause metabolic changes, resulting in reduced glucose transport and cerebral ischaemia. To evaluate the frequency of the occurrence of hyperglycaemia, samples were evaluated for glucose levels in three groups of patients. Group 1 (n = 5) consisted of infants undergoing standard bypass and moderate hypothermia (26 degrees C). Group 2 (n = 5) were infants undergoing low-flow bypass and profound hypothermia (20 degrees C). Group 3 (n = 5) was comprised of infants undergoing total circulatory arrest and profound hypothermia (18 degrees C). Glucose samples were taken preoperatively, during hypothermic bypass, during rewarming and 1-h postoperatively. In group 1, blood glucose levels remained within the normal range (65-100 mg/dl) throughout bypass and in the 1-h postoperative sample. In group 2, blood glucose levels remained within the normal range preoperatively and during the hypothermic bypass period. However, during the rewarming period, the glucose level rose to 185 +/- 17.2 mg/dl. The 1-h postoperative level was also increased to 168 +/- 16.5 mg/dl. Group 3, like group 2, showed that the preoperative and hypothermic glucose values were within the normal range and the rewarming, 133 +/- 29.4, and the 1 h, 130 +/- 33.3 mg/dl, glucose values were hyperglycaemic. This study indicates that blood glucose levels should be monitored routinely, both during and after CPB.