Left Ventricular Tonic Contraction as a Novel Biomarker of Cardiomyopathy in Duchenne Muscular Dystrophy

Dilated cardiomyopathy (DCM) inevitably afflicts patients with Duchenne muscular dystrophy (DMD) as a consequence of cell death induced by unguarded calcium influx into cardiomyocytes. This mechanism may also inhibit muscle relaxation in early stages of cardiomyopathy. ACE inhibition (ACEi) is known to delay the onset and slow the progression of DCM in DMD. The objective of this study is to use echocardiography to assess for preclinical cardiac changes consistent with intracellular calcium dysregulation before the onset of overt ventricular dysfunction, and to evaluate how prophylactic ACEi may alter these pre-cardiomyopathic changes in the pediatric DMD population. We examined 263 echocardiograms from 70 pediatric patients with DMD. We defined abnormal tonic contraction (TC) as left ventricular internal dimension in diastole (LVIDd) Z-score < ?1.5. In our cohort, we found that TC is detectable as early as 8 years of age, and most commonly affects patients between 11 and 15 years. This effect was independent of LV mass and systolic function. Prophylactic ACEi decreased the incidence of TC (p = 0.007) and preserved cardiac function (p < 0.0001). Left ventricular TC often precedes DCM in DMD, most commonly affecting the 11- to 15-year-old age range. TC is not related to ventricular hypertrophy, but rather may be a clinical correlate of the “calcium hypothesis” of DMD pathophysiology. LV TC is thus a promising biomarker for early detection of cardiomyopathy in DMD. ACEi prophylaxis suppresses LV TC and delays the development of DCM in DMD.     

Risk Factors for Interstage Mortality Following the Norwood Procedure: Impact of Sociodemographic Factors

Interstage mortality remains significant for patients undergoing staged palliation for hypoplastic left heart syndrome and other related single right ventricle malformations (HLV). The purpose of this study was to identify factors related to demographics, socioeconomic position, and perioperative course associated with post-Norwood hospital discharge, pre-stage 2, interstage mortality (ISM). Medical record review was conducted for patients with HLV, born from 1/2000 to 7/2009 and discharged alive following the Norwood procedure. Sociodemographic and perioperative factors were reviewed. Patients were determined to have ISM if they died between Norwood procedure hospital discharge and stage 2 palliation. Univariable and multivariable logistic regressions were performed to identify risk factors associated with ISM. A total of 273 patients were included in the analysis; ISM occurred in 32 patients (12 %). Multivariable analysis demonstrated that independent risk factors for interstage mortality included teen mothers [adjusted odds ratio (AOR) 6.6, 95 % confidence interval (CI) 1.9–22.5], single adult caregivers (AOR 4.1, 95 % CI 1.2–14.4), postoperative dysrhythmia (AOR 2.7, 95 % CI 1.1–6.4), and longer ICU stay (AOR 2.7, 95 % CI 1.2–6.1). Anatomic and surgical course variables were not associated with ISM in multivariable analysis. Patients with HLV are at increased risk of ISM if born to a teen mother, if they lived in a home with only one adult caregiver, suffered a postoperative dysrhythmia, or experienced a prolonged ICU stay. These risk factors are identifiable, and thus these infants may be targeted for interventions to reduce ISM.     

Now how do we get them home? Outpatient care of pediatric patients on mechanical circulatory support

The last five yr have been monumental for the pediatric heart failure community. In the US, the most notable has been the FDA approval of the first pediatric specific device (Berlin Heart EXCOR^®; Berlin Heart, Inc., Berlin, Germany). Subsequently, the field of heart failure has gained a great deal of knowledge regarding the nuances of MCS in children. Despite FDA approval in the US, the Berlin EXCOR^® is only currently indicated for in‐hospital use. Due to the limitations with discharge and the positive in‐ hospital experiences with the Berlin EXCOR^®, there has been an increased interest in the implantation of adult durable devices into children. While many institutions have focused their intial efforts on the first phase of care within the hospital, they are now ready to tackle the challenge of how to safely transition children to the community setting.     

Abdominal transplantation for unresectable tumors in children: the zooming out principle

Purpose

To present our experience in abdominal transplantations to manage unresectable abdominal neoplasms in children and to describe the role of extensive surgeries in such cases.

Methods

This is a retrospective study of 22 abdominal transplantations in 21 patients for abdominal tumors over 16 years. Transplantation techniques included liver transplant (LT), multivisceral transplant (MVTx), and intestinal autotransplant (IA). Follow-up intervals ranged from 0.3 to 168 months (median 20 months).

Results

LT alone was performed in 15 patients for primary malignant (11) and benign (4) liver tumors. Pathological classification included HB hepatoblastoma (6), HCC hepatocellular cancer (3), hepatic epithelioid hemangioendothelioma HEH (1), angiosarcoma (1), benign vascular tumors (3), and adenoma (1). IA was performed in four patients for lesions involving the root of the mesentery; tumors of the head of pancreas (3) and mesenteric hemangioma (1). MVTx was performed in 2 patients for malignancies; pancreaticoblastoma (1), recurrent hepatoblastoma (1), and in one patient as a rescue procedure after IA failure. Four of the eleven patients who underwent LT for malignant liver tumor had metastatic disease at presentation. Six of them died of recurrent neoplasm (3), transplant-related complications (2), and underlying disease (1). All LT patients who had benign tumors are alive with functioning grafts. All IA patients survived and are on an oral diet, with one patient requiring TPN supplementation. One of the three patients who underwent MVTx died of metastatic disease.

Conclusions

Allo/auto transplantation for abdominal tumors is a valuable modality when conventional treatments fail or are not feasible.