Jonah Odim

Atrial Extracellular Matrix Remodeling and the Maintenance of Atrial Fibrillation

Background—Remodeling occurs in both ventricle and atrium in dilated cardiomyopathy and heart failure. However, the alteration of atrial extracellular matrix components during remodeling and its effect on the electrical remodeling and atrial arrhythmia have never been explored. Methods and Results—Atrial tissue samples of 53 explanted hearts from patients with dilated cardiomyopathy and end-stage heart failure who underwent heart transplantation were examined. Nineteen patients had permanent atrial fibrillation (PmAF), 18 had persistent AF (PsAF), and 16 had no documented AF (NAF). Sixteen donor left atria (LA) were used as controls (CNs). Western Blot analysis revealed a selective downregulation of tissue inhibitor of metalloproteinase (TIMP)-2 in PmAF and PsAF groups compared with the NAF and CN groups and an upregulation of atrial metalloproteinase (MMP)-2 that was most pronounced in the PmAF group followed by the PsAF and NAF groups. Immunofluorescent staining revealed that in the LA, type I collagen volume fraction (CVF-I) increased significantly in the PmAF group followed by the PsAF and NAF groups compared with that in CN. LA CVF-I significantly correlated with LA dimension and TIMP-2 to MMP-2 ratio. In the PsAF group, CVF-I/CVF-III ratio was significantly correlated with AF duration and the frequency of AF recurrence. Conclusions—Atrial extracellular matrix remodeling manifested by the selective downregulation of TIMP-2 along with upregulation of MMP-2 and CVF-I in the atrium is associated with the development of sustained atrial fibrillation in patients with cardiomyopathy and heart failure.

Surgical pathology of cardiac tumors. Two decades at an urban institution.

BACKGROUND As better diagnostic techniques and new operative approaches are developed pathologists will be called upon more often for intraoperative consultation to render a pathologic diagnosis and assess adequacy of resection. METHODS We conducted a retrospective survey of all patients presenting to our institution from 1979 to 1999. The surgical pathology and cardiothoracic surgery databases were used to identify these patients. RESULTS Of the 29 patients with primary cardiac neoplasms, 15 were male and 14 female. The mean age at surgery was 51.9 years (range, 7 months to 84 years). Twenty-six of 29 patients had a benign pathological diagnosis. The majority (20/26) of the benign tumors were myxomas. Other benign pathologic diagnoses included rhabdomyoma, fibroma, papillary fibroelastoma, localized fibrous tumor and lipoma. Three out of 29 were malignant: 1 fibrosarcoma, 1 malignant mesenchymoma, and 1 rhabdomyosarcoma. Six of the patients presented with thrombo-embolism, 8 with congestive heart failure symptoms, and three with chest discomfort. Five were asymptomatic or the neoplasm was an incidental finding. 2-D echocardiography established the diagnosis in all of the patients except one. Twenty-two of the 29 tumors were located in the atria (LA=15, RA=6, biatrial=1) and 5 in the ventricles (LV=1, RV=2, biventricular=2). Two patients in this series were referred for reresection. A median sternotomy approach was used for tumor extirpation in all patients. Three of the 29 patients have died at a mean follow-up period of 757 days (median, 118 days). There were two late deaths and one hospital (early) death in a reoperation for recurrent malignancy employing cardiac autotransplantation. One additional patient required cardiac reoperation. CONCLUSIONS Primary cardiac neoplasms are rare and occur less commonly than metastatic disease of the heart. Congestive heart failure symptoms and thrombo-embolism account for close to half of the presenting signs and symptoms. 2-D echocardiography remains the mainstay of detection. Distinguishing between benign and malignant, thrombus and vegetation, and extracardiac structure is usually established by the size, shape, mobility and attachment of the mass. Clinical presentation and transesophageal echocardiographic views are extremely helpful in sharpening the accuracy of the diagnosis. Since surgery is the only reliable therapy pathologists will be called upon for intraoperative consultation. The majority of the neoplasms are benign. Malignant neoplasms are difficult to excise completely and portend a grave prognosis.

Staged repair of pulmonary atresia with ventricular septal defect and major aortopulmonary collateral arteries: Experience with 104 patients

OBJECTIVE To determine the early and intermediate-term outcome of the staged repair used to treat children with pulmonary atresia with ventricular septal defect and major aortopulmonary collateral arteries. METHODS We reviewed a retrospective case series of 104 patients with this complex lesion. Information was obtained from medical records and referring physicians. RESULTS Of the 104 patients treated with the staged repair, 58 achieved completion of anatomic repair. The 10-year mortality was 16.5%. In the patients with complete repair, the median right-to-left ventricle pressure ratio was 0.5. The overall surgical reoperation rate was 17%, and 15.5% of patients required postoperative interventional cardiac catheterization. In the multivariate analysis, the number of collateral vessels incorporated in the repair was found to be an independent risk factor for postoperative mortality and an elevated right-to-left ventricle pressure ratio after complete repair. CONCLUSION The staged repair can be successfully used to treat patients with pulmonary atresia with ventricular septal defect and major aortopulmonary collateral arteries. This method yields a relatively low mortality with good functional results.

Staged surgical approach to neonates with aortic obstruction and single-ventricle physiology

BACKGROUND The surgical management of neonatal systemic outflow obstruction and complex single ventricle pathology is variable. METHODS In 15 neonates (12 boys and 3 girls) with complex forms of single-ventricle pathology and aortic coarctation or interruption, an initial strategy of banding the pulmonary artery and repair of the obstruction from a left thoracotomy was undertaken. RESULTS The median age at operation was 6 days (range 2 to 33 days) and the median weight was 3.3 kg (range 2 to 4.6 kg). There were no early deaths and one late death after the initial surgical palliation. Of the 14 survivors, 8 have undergone a bidirectional cavopulmonary anastomosis. The median age for bidirectional Glenn was 9.75 months (range 3.5 to 26 months). Seven infants have required Damus-Kaye-Stansel reconstruction for subaortic obstruction (one early death). The median age of the Damus-Kaye-Stansel procedure was 4 months (range 3 weeks to 9 months). Thirteen of 15 patients (87%) are alive and 6 have proceeded to a Fontan operation (median follow-up 68 months). A single failing Fontan required takedown to bidirectional Glenn and central shunt. CONCLUSIONS Our experience suggests that this high-risk subgroup of neonates with aortic obstruction and single-ventricle pathophysiology is safely managed by initial pulmonary artery banding palliation and repair of aortic obstruction. This strategy, careful surveillance, and early relief of subaortic stenosis can maintain acceptable anatomy and hemodynamics for later bidirectional Glenn and Fontan procedures.

Post‐transplant lymphoproliferative disorder following pediatric heart transplantation

Abstract:  Immunosuppression after heart transplantation is implicated in development of post‐transplant lymphoproliferative disorder (PTLD). Despite a higher prevalence of PTLD in children, there is scarce knowledge about incidence, pathophysiologic mechanisms and risk factors for PTLD in pediatric recipients of cardiac allografts. We examined retrospectively the medical records of all 143 pediatric patients (mean age 9.2 ± 6.1 yr) who received donor allografts between 1984 and 2002 and survived over 30 days. Five children (3.5%) developed PTLD over a mean follow‐up period of 41.1 ± 46.0 months. Time from transplant to diagnosis of PTLD ranged from 3.9 to 112 months (mean 48.0 ± 41.9 months). Excluding PTLD, no other malignancies were found in this population. Actuarial freedom from PTLD was 99.2%, 99.2% and 96.2% at 1, 2, and 5 yr, respectively. Children who developed PTLD were more likely (by univariate analysis) to have been Rh negative (p = 0.01), Rh mismatched (p = 0.003), Epstein–Barr virus (EBV) seronegative (p = 0.001) and transplanted for congenital heart disease (p < 0.02). PTLD was associated with significant morbidity and mortality with a mean survival following diagnosis of 21.2 months. PTLD is a serious complicating outcome of cardiac transplantation that occurs in approximately 3.5% of children. Aside of immunosuppression, risk factors in this series for developing PTLD include EBV seronegativity and Rh negative status and mismatch. Non‐hematogenous malignancies are rare in light of short allograft half‐life.

Equivalent performance of epicardial versus endocardial permanent pacing in children: a single institution and manufacturer experience.

BACKGROUND Children requiring permanent pacing have a lifelong need for follow-up. Epicardial leads have traditionally fared worse than endocardial counterparts. We tested the hypothesis that steroid-eluting epicardial and endocardial leads had equivalent outcomes. METHODS We reviewed medical records of 148 children, mean age 8.2 +/- 4.8 years, in whom a dual-chamber pacemaker system with steroid-eluting leads from a single manufacturer was implanted. Primary outcome was mortality. Secondary outcomes included freedom from lead failure and pacemaker system reintervention. Loss of capture-sensing, lead displacement-fracture, exit block, and high thresholds constituted lead failure. Reintervention included need for lead revision or generator change. RESULTS There was no early mortality. Late mortality occurred once (0.5 +/- 0.5 deaths/1,000 patient-months) and eight times (3.4 +/- 1.2 deaths/1,000 patient-months) in the endocardial and epicardial groups, respectively. The relative hazard of endocardial versus epicardial site for lead failure was 0.408 (p = 0.038) and for reintervention was 0.629 (p = 0.002). Endocardial and epicardial groups differed in important ways: concomitant cardiac surgery 5% (3 of 61) versus 27% (27 of 99); congenital heart disease 33% (20 of 61) versus 90% (89 of 99); single ventricle physiology 13% (8 of 61) versus 52% (51/99); and age (10.5 +/- 4.5 years vs 5.5 +/- 5.2 years). Adjusting for these covariants, the relative hazard for freedom from lead failure for endocardial versus epicardial leads was 0.546 (p = 0.360). The adjusted relative hazard for freedom from reintervention was 0.157 (p = 0.045). CONCLUSIONS Technologic advances attenuate important differences in lead failure rates between endocardial and epicardial steroid-eluting pacing leads and thus bridge the performance gap between these fixation modes.

Aortic Valve-Sparing Repair with Autologous Pericardial Leaflet Extension Has Low Long-Term Mortality and Reoperation Rates in Children and Adults

OBJECTIVES We sought to establish whether there was a difference in outcome after aortic valve repair with autologous pericardial leaflet extension in pediatric and adult populations. METHODS In our study, 128 patients (pediatric and adult) underwent valvular pericardial extension repair at our institution from 1997 through 2006. The patients were divided into either the pediatric group (< or =18 years of age; n = 54/128, 42%), with a mean age of 8.4 +/- 5.4 (range, 0-17 years), or the adult group (n = 74/128, 58%), with a mean age of 48.9 +/- 19.7 (range, 19-85 years). The endpoints of the study were mortality and reoperation rates. RESULTS Thirty-day mortality for the adult group was 0, and for the pediatric group it was 1/54 (1.8%), with no statistical difference (P = .1) between the groups. Late mortality for the pediatric group was 2/54 (3.7%) and in the adult group was 2/74 (2.7%). There was no statistical difference (P = .12) between the groups. In the pediatric group, there were 6 total reoperations (6/54) in 5 patients, with one patient undergoing reoperation twice. From these 6 cases, 3 were re-repair and 3 had aortic valve replacement; the mean interval between original repair and reoperation was 4.3 +/- 2.5 years (range, 0.1-7.7 years). In the adult group, there were 5 total reoperations (5/74). From these 5 cases, 3 had aortic valve replacement and 2 re-repair; the mean interval between original repair and reoperation was 3.5 +/- 3 years (range, 0.1-7 years). There was no statistical difference in the reoperation rate between the 2 groups (P= .38). At late follow-up, 82% of all patients in the adult group had no aortic regurgitation or only a trace (grades 0 and 1) and 78% of all patients in the pediatric group had no aortic regurgitation or only a trace (grades 0 and 1). There was no statistical difference in either aortic regurgitation (P = .06) or aortic stenosis (P = .28) between the 2 groups. CONCLUSIONS Aortic valve repair with autologous pericardial leaflet extension has low mortality and morbidity rates, as well as good mid-term durability in both the pediatric and the adult groups.

Heart transplantation in the young and elderly

AbstractIntroduction: Heart transplantation has become an acceptable treatment in pediatric patients with end-stage heart disease and complex congenital heart disease. The liberalization of recipient eligibility criteria, mainly age, along with the expansion of the donor pool has resulted in the acceptable transplantation of older recipients. Methods: Between July 1994 and June 1998, 39 pediatric patients aged 16 days to 17.6 years (median 6.68 years) and 123 elderly patients aged 60 to 74.8 years (median 64.1 years) were transplanted at our institution. In the pediatric group, 19 had idiopathic dilated cardiomyopathy (DCM) (46 %), 14 had congenital heart disease (34 %), 4 had other etiologies of cardiomyopathy (10 %), 2 had transplant coronary artery disease (TCAD) (5 %), and 1 each had acute rejection and graft failure. In the elderly group, 71 had ischemic cardiomyopathy (58 %), 38 had DCM (31 %), 9 had other forms of cardiomyopathy (7 %), and 5 had TCAD (4 %). Results: Thirty-day, 1-year, and 4-year survival_was 97.4 %, 87.2 %, and 70.9 % for the pediatric group and 92.7 %, 81.3 %, and 79.3 % for the elderly_group. One and 4-year freedom from TCAD was_100.0 % and 85.3 % for the pediatric group and 91.9 % and 83.3 % for the elderly group. Conclusions:[emsp3 ]Orthotopic heart transplantation is effective for the treatment of irreparable congenital and end-stage heart disease. It provides excellent long-term results in both the very young and elderly.

The incisional pulmonary artery band

Occasionally early definitive repair of congenital heart disease carries prohibitive mortality, and interval pulmonary artery banding is necessary to protect the pulmonary arterial bed and improve systemic perfusion or prepare a systemic left ventricle for a later arterial switch operation. We describe our technique for effectively banding the pulmonary artery.

Spinal cord infarct after arterial switch associated with an umbilical artery catheter

Paraplegia after an open heart operation in a neonate is a rare complication. We report a case of a infant in whom paraplegia developed after a successful arterial switch operation for transposition of the great arteries. The infant was monitored and resuscitated in the preoperative period with umbilical arterial and venous catheter tips located in the midthoracic region. He likely suffered a clinically silent thromboembolic event predisposing him to a localized hemorrhagic infarction during the repair.