Heading toward the future of pediatric heart failure with continuous-flow ventricular assist devices

Variability in clinical decision-making for ventricular assist device implantation in pediatrics

BACKGROUND

Minimal data exist on clinical decision-making in VAD implantation in pediatrics. This study aims to identify areas of consensus/variability among pediatric VAD physicians in determining eligibility and factors that guide decision-making.

METHODS

An 88-item survey with clinical vignettes was sent to 132 pediatric HT cardiologists and surgeons at 37 centers. Summary statistics are presented for the variables assessed.

RESULTS

Total respondents were 65 (72% cardiologists, 28% surgeons) whose centers implanted 1-5 (34%), 6-10 (40%), or >10 (26%) VADs in the past year. Consensus varied by patients' age, diagnosis, and Pedimacs profile. Highest agreement to offer VAD (97%) was a mechanically ventilated teenager with dilated cardiomyopathy. Patients stable on inotropes were less likely offered VAD (11%-25%). SV infant with Pedimacs profile 2 had the most varied responses: 37% offered VAD; estimated survival ranged from 15% to 90%. Variables considered for VAD eligibility included mild developmental delays (100% offered VAD), moderate-severe behavioral concerns (46%), cancer in remission >2 years (100%), active malignancy with good prognosis (68%) or uncertain prognosis (36%), and BMI >35 (74%) or <15 (69%). Most respondents (91%) would consider destination therapy VADs in pediatrics, though not currently feasible at 1/3 of centers. Factors with greatest influence on decision-making included HT candidacy, families' goals of care, and risks of complications.

CONCLUSIONS

Significant variation exists among pediatric VAD physicians when determining VAD eligibility and estimating survival, which can lead to differences in access to emerging technologies across institutions. Further work is needed to understand and mitigate these differences.

R-Wave Modified Tissue Doppler Imaging Myocardial Performance Index for the Assessment of Cardiac Function in Children with Congestive Heart Failure: A Feasibility Study

Background

The aim of this study was to evaluate the feasibility of an R-wave modified tissue Doppler imaging (TDI) myocardial performance index (MPI), or MPI TDI-R, for the assessment of cardiac function in children with congestive heart failure (CHF).

Material/Methods

Forty children with CHF and 40 normal children were evaluated using the modified pediatric Ross heart failure grading system. TDI recorded the spectrum of diastolic function at the mitral valve annulus to measure the MPI. Twelve-lead electrocardiogram (ECG) measured the R-wave in the QRS complex, resulting in the modified MPI TDI-R. Correlation between the MPI TDI-R, other echocardiographic indices, and the Ross heart failure grades were analyzed, with reproducibility analysis.

Results

Compared with normal children, the MPI TDI and MPI TDI-R were significantly increased in the pediatric CHF group (P<0.01). The MPI TDI-R was significantly correlated with other indices of cardiac function and Ross grading for CHF in children (r=0.769). The MPI TDI-R showed good correlation with the findings of the MPI TDI, calculated by traditional methods. Receiver-operating characteristic (ROC) curve analysis showed that the MPI TDI-R had a sensitivity of 67.5%, and a specificity of 97.5%. The reproducibility of the MPI TDI-R was confirmed to be superior when compared with the non-modified MPI TDI.

Conclusions

This feasibility study showed that the modified MPI TDI-R, formed by combining the MPI TDI with synchronous surface ECG measurements, was simple to perform, reproducible, and provided a specific index for the assessment of cardiac function in children with CHF.