Use of Isosorbide Dinitrate/Hydralazine in the Pediatric Cardiac Population

Abstract

<h3>Purpose</h3> The combination of isosorbide dinitrate/hydralazine (ISDN/HYD) offers direct arterial and venous vasodilation without adversely affecting renal function. It is used as an adjunct to standard heart failure therapies in adults with reduced ejection fraction. ISDN/HYD is an attractive option in pediatric cardiac patients who may not tolerate angiotensin converting enzyme inhibitors due to renal dysfunction from inadequate systemic cardiac output, nephrotoxic medications, or young age. Given the lack of published reports of its use in children, we report our experience with ISDN/HYD in a heterogeneous population of pediatric cardiac patients. <h3>Methods</h3> From an internal database, we identified all patients treated with ISDN/HYD. Patient characteristics at ISDN/HYD initiation, 3-months, discontinuation, and latest follow-up were abstracted from the chart. ISDN/HYD was dosed TID at a dose ratio of 1:2 ISDN:HYD. <h3>Results</h3> There were 59 patients treated with ISDN/HYD for a mean duration of 14 ± 14 months. Patient characteristics are summarized in Table 1. The mean age was 3.8 years, while those with single ventricle anatomy were mostly infants. Over half had a prior diagnosis of acute kidney injury. The majority of patients were initiated during a hospitalization. In addition to heart failure, ISDN/HYD was used in stage 1 single ventricle patients to reduce pulmonary over-circulation. Brain natriuretic peptide decreased from initiation to 3 months (782 vs 312 pg/mL, p=0.0007, n = 42), and left ventricular fractional shortening increased (29 vs 32%, p=0.013, n=32). <h3>Conclusion</h3> As demonstrated in this case series, ISDN/HYD is used across a heterogeneous pediatric cardiac population where acute kidney injury is common. Short-term follow up after ISDN/HYD initiation showed a reduction in BNP and a modest improvement in left ventricular systolic function. Further study is needed to define indications, side effects, and better understand outcomes of ISDN/HYD use in the pediatric cardiac population.