Implantation of a HeartMate 3 ventricular assist device in a 21-kg pediatric patient with Fontan failure

Impact of Ventricular Dominance on Long-Term Fontan Outcomes: A 25-year Single-institution Study

BACKGROUND

The long-term impact of ventricular dominance on Fontan outcomes is controversial. This study examined this issue in a 25-year cohort.

METHODS

Patients undergoing the Fontan operation at a single institution (Duke University Medical Center, Durham, NC) from October 1998 to February 2022 were reviewed. Primary outcomes were transplant-free survival and Fontan failure (death, heart transplantation, takedown, protein-losing enteropathy, or plastic bronchitis). Secondary outcomes included hospital and intensive care lengths of stay. Kaplan-Meier methodology compared outcomes by ventricular dominance. Multiphase parametric risk hazard analysis identified risk factors for primary outcomes.

RESULTS

There were 195 patients (104 right ventricular dominant) included in the study. Baseline characteristics were comparable. Perioperative survival was similar (right ventricular dominant, 98%; non-right ventricular dominant, 100%; P = .51). The proportion of patients experiencing death or heart transplantation was 8.7%, and the rate of Fontan failure was 11.8% during a median follow-up of 4.5 years (interquartile range, 0.3-9.8 years). Right ventricular-dominant patients had reduced transplant-free survival (10-year estimates: 80% [95% CI, 70%-91%] vs 92% [95% CI, 83%-100%]; P = .04) and freedom from Fontan failure (73% [95% CI, 62%-86%] vs 92% [95% CI, 83%-100%]; P = .04). Multiphase hazard modeling resolved 2 risk phases. The early phase spanned from surgery to approximately 6 months afterward. The late phase spanned from approximately 6 months after surgery onward. In multivariable analysis, right ventricular dominance was an independent risk factor for death or heart transplantation (parameter estimate, 1.3 ± 0.6; P = .04) and Fontan failure (1.1 ± 0.5; P = .04) during the second phase, with no significant first-phase risk factors.

CONCLUSIONS

Right ventricular dominance was associated with long-term complications after Fontan procedures, including mortality, heart transplantation, and Fontan failure. This cohort may benefit from heightened surveillance in a multidisciplinary Fontan clinic after the perioperative period.

Use of Intracorporeal Durable LVAD Support in Children Using HVAD or HeartMate 3-A EUROMACS Analysis

Purpose: The withdrawal of HVAD in 2021 created a concern for the pediatric population. The alternative implantable centrifugal blood pump HeartMate 3 has since been used more frequently in children. This paper analyses the outcome of children on LVAD support provided with an HVAD or HM3. Methods: A retrospective analysis of the EUROMACS database on children supported with VAD < 19 years of age from 1 January 2009 to 1 December 2021 was conducted. All patients with an LVAD and either an HVAD or HM3 were included. Patients with missing data on VAD status and/or missing baseline and/or follow up information were excluded. Kaplan-Meier survival analysis was performed to evaluate survival differences. Analyses were performed using Fisher's exact test. Results: The study included 150 implantations in 142 patients with 128 implants using an HVAD compared to 28 implants using an HM3. Nine patients (6%) needed temporary right ventricular mechanical support, which was significantly higher in the HM3 group, with 25% (p: 0.01). Patients in the HVAD group were significantly younger (12.7 vs. 14.5 years, p: 0.01), weighed less (45.7 vs. 60 kg, p: <0.000) and had lower BSA values (1.3 vs. 1.6 m2, p: <0.000). Median support time was 204 days. Overall, 98 patients (69%) were discharged and sent home, while 87% were discharged in group HM3 (p: ns). A total of 123 children (86%) survived to transplantation, recovery or are ongoing, without differences between groups. In the HVAD group, 10 patients (8%) died while on support, whereas in 12% of HM3 patients died (p: 0.7). Conclusions: Survival in children implanted with an HM3 was excellent. Almost 90% were discharged and sent home on the device.

Advances in Extracorporeal Support Technologies in Critically Ill Children

The field of pediatric heart failure is evolving, and the patient population is growing as survival after complex congenital heart surgeries is improving. Mechanical circulatory support and extracorporeal respiratory support in critically ill children has progressed to a mainstay rescue modality in pediatric intensive care medicine. The need for mechanical circulatory support is growing, since the number of organ donors does not meet the necessity. This article aims to review the current state of available mechanical circulatory and respiratory support systems in acute care pediatrics, with an emphasis on the literature discussing the challenges associated with these complex support modalities.

Outcomes in patients with smaller body surface area after HeartMate 3 left ventricular assist device implantation

BACKGROUND

Due to anatomic and physiologic concerns, prior generations of the left ventricular assist devices (LVAD) have frequently been denied to patients with small body size. However, outcomes in patients with small body surface area (BSA) following HeartMate 3 (HM3) LVAD implantation remain relatively unknown.

METHODS

A cohort of 220 patients implanted at a single center was divided into two groups: BSA ≤1.8 m² (small BSA, n = 37) and BSA >1.8 m² (large BSA, n = 183). We investigated baseline characteristics and clinical outcomes including survival and incidence of adverse events.

RESULTS

Small BSA patients were older (60 vs. 57 years), more likely female (60% vs. 20%), had a lower body mass index (24 vs. 32 kg/m² ), lower incidence of diabetes (32% vs. 51%), history of stroke (5% vs. 19%), and left ventricular thrombus (0% vs. 11%). They had smaller left ventricular end diastolic diameter (64.8 vs. 69.3 mm). Pump speed and pump flows at discharge were lower in the small BSA group. Survival at 1 year and 2 years was 86% versus 87% and 86% versus 79% for small versus large BSA groups (p = 0.408), respectively. The rates of adverse events were similar between groups and there were no cases of confirmed pump thrombosis. The incidence of readmissions for low flow alarms was higher in the small BSA group (0.55 vs. 0.24 EPPY).

CONCLUSIONS

These findings demonstrate comparable outcomes in patients with small body size and suggest that this parameter should not be an exclusion criterion on patients who are otherwise candidates for HM3 LVAD implantation.