David N. Rosenthal

The ACTION score was internally validated to predict mortality after pediatric ventricular assist device (VAD) placement. This study aims to externally validate the ACTION score and compare its performance to the INTERMACS profile for prediction of mortality in pediatric VAD candidates. The publicly available Pedimacs dataset (531 patients) was used for external validation. The Pedimacs dataset as well as a contemporary ACTION dataset (1,304 patients) were used to compare the performance of the ACTION score and INTERMACS profile. A statistically significant linear trend in the proportion of death across increasing ACTION scores ( p < 0.0001) was observed in the Pedimacs dataset, with a receiver operating characteristic (ROC) curve demonstrating an area under the curve (AUC) of 0.71. Both the ACTION score and the INTERMACS profile demonstrated a significant linear trend in the proportion of death across scores in the ACTION dataset. Receiver operating characteristic analysis demonstrated an AUC of 0.71 and 0.58 for the ACTION score and INTERMACS profile, respectively. The ACTION score is externally validated with the Pedimacs dataset and is a fair predictor of mortality. The ACTION score performed better than the INTERMACS profile in predicting mortality using both historical Pedimacs data and contemporary ACTION data.

Duchenne muscular dystrophy (DMD) is an X‐linked genetic neuromuscular disorder that is caused by a mutation in the dystrophin gene. The disease is characterized by progressive weakness of skeletal muscle, resulting in loss of ambulation and eventually respiratory insufficiency. Cardiac muscle is also involved, and cardiomyopathy is a prominent feature of DMD. The care of patients with DMD has changed in important ways over the past 15 years, with the use of chronic steroid therapy combined with noninvasive respiratory support such as continuous positive airway pressure for home use. More recently, therapies targeting specific genetic mutations in DMD have been approved, using gene‐skipping oligonucleotides, and many other novel therapies are being evaluated in clinical trials, including mini‐dystrophin genes delivered by viral vectors. In view of this new era in care and outcomes, it is appropriate to review the role of advanced cardiac therapies such as ventricular assist devices and heart transplantation in the care of this population. In September 2024, a group of healthcare professionals with expertise in DMD and heart failure convened to review this topic; the consensus opinion of this group (DMD Cardiac Care Consortium) is presented in this manuscript.

BACKGROUND: Cardiac resynchronization therapy (CRT) is an important therapeutic option in selected pediatric patients and patients with congenital heart disease with reduced systemic ventricular ejection fraction (SVEF). However, the identification of optimal responders is challenging. This study aimed to identify predictors of response to CRT in children and patients with congenital heart disease at 5 large quaternary referral centers. METHODS: Patients were aged P =0.013), biventricular circulation ( P =0.022), systemic left ventricle ( P =0.021), and conduction delay to the lateral wall of the systemic ventricle ( P =0.01) were associated with a positive response. For the assessment of the secondary outcome, 324 controls were identified. Median follow-up is 5.1 (interquartile range, 2.0–8.6) years. Almost all subgroups demonstrated improved SVEF trend with CRT, except those with systemic right ventricle ( P =0.69) or without prior single-site pacemaker ( P =0.20). CONCLUSIONS: CRT in children and patients with congenital heart disease frequently results in an improvement in SVEF. Those with lower SVEF, conduction delay to the lateral wall of the systemic ventricle, and those with a systemic left ventricle are most likely to respond.

BACKGROUND: Fontan circulatory failure (FCF) is a chronic state in palliated single ventricle heart disease with high morbidity and mortality rates, including heart failure, multisystem end-organ disease, and need for heart transplant. Specific FCF morbidities have not been rigorously defined, limiting study of how FCF morbidities affect pre–heart transplant and post–heart transplant outcomes. We hypothesized that FCF-related morbidities affect survival from heart transplant waitlisting through 1 year after heart transplant. METHODS: This 20-center, retrospective cohort study collected demographic, medical/surgical history, waitlist, and peri- and post–heart transplant data, and a priori defined FCF-specific morbidities, in Fontan patients who were listed for heart transplant from 2008 through 2022. Univariate 2-group statistics compared surviving individuals with those who died anytime from waitlisting to 1 year after heart transplant, died on the waitlist, or underwent transplant and died within 1 year after transplant. Using covariates from both univariate analyses, multivariable logistic regression determined the primary study outcome of independent FCF risk factors for death between waitlist and 1 year after heart transplant. RESULTS: Of 409 waitlisted patients, 24 (5.9%) died on the waitlist. Of the 341 (83.4%) who underwent transplant, 27 (8.5%) did not survive to 1 year. Univariate risk factors for waitlist death included higher aortopulmonary collateral burden, >1 hospitalization in the previous year, younger age, sleep apnea, higher New York Heart Association class, nonenrollment in school or work, and single-parent home. Risk factors for 1-year post–heart transplant mortality included hypoplastic left heart syndrome diagnosis, patent fenestration, anatomic Fontan obstruction, clinical cyanosis (pulse oximetry 1 hospitalization in the year before waitlisting (adjusted odds ratio, 2.0 [95% CI, 1.0–4.1]; P =0.05) and clinical cyanosis (adjusted odds ratio, 5.0 [95% CI, 1.8–13.4]; P =0.002). CONCLUSIONS: Patients with Fontan palliation selected for heart transplant have substantial mortality rates from waitlisting through transplant. Among FCF-specific morbidities, cyanosis is associated with worsened survival and necessitates further study. Clinical morbidity of any type requiring repeated hospital admission also should prompt consideration of heart transplant.

Background: With advances in respiratory care allowing for improved survival, cardiomyopathy has emerged as the leading cause of death in patients with Duchenne Muscular Dystrophy (DMD). As end‐stage heart failure emerges as the primary life‐limiting complication in DMD patients, their consideration for advanced heart failure therapies, including ventricular assist devices (VADs) and/or heart transplantation (HT), is increasing. To date, however, there are few published reports of HT in DMD patients. Methods: We report a case of HT in an 18‐year‐old young man with DMD, end‐stage heart failure, respiratory insufficiency requiring nocturnal noninvasive ventilation, and retained ambulation with the use of a cane, who was declined for VAD and HT at an adult heart transplant center; he then received an LVAD, followed by HT after 362 days of support at a pediatric center. Results: At 3.5 years of follow‐up, the patient has excellent graft function and modestly improved pulmonary mechanics, though has experienced a functional decline from ambulatory status to the need for full assistance with activities of daily living. Conclusions: This case underscores the importance of individual consideration for HT in patients with DMD, provides additional insight into the unique risks of VAD support in these patients, and further builds upon the existing experience that acceptable post‐HT outcomes are achievable in this population.