*Hypoplastic Left Heart Syndrome DOI: http://dx.doi.org/10.5772/intechopen.104723*

#### **Figure 9.**

*Mitochondrial respiration in SV-CHD patients and* Ohia *HLHS mutant mouse heart. (a, b) Mitochondrial respiration in the PBMCs of SV-CHD patients ≥10 years old with and without HF vs. age-matched controls (a) and BV-CHD patients (b). (c, d) Mitochondrial respiration in the PBMCs of HLHS-CHD patients ≥10 years old with and without HF vs. age-matched controls (c) and BV-CHD patients (d). (e–h) Basal OCR in LV and RV heart tissue from E14.5-16.5* Ohia *line with* Sap130/Pcdha9 *mutations known to cause HLHS. This analysis was obtained using the Seahorse Analyzer. (e, f) Data was obtained from litters comprising wild-type (WT) (n = 7) and HLHS (n = 4). (g, h) Quantitively analysis of 5 Sap130/Pcdha9 mutants with normal cardiac anatomy without HLHS (e, f) and six WT controls. (a–d) Mean ± SEM with one-way ANOVA test. Subjects' numbers are indicated in the legend for the graphs. (e–h) Bar graphs show mean ± SEM with Student's t-test. Each dot represents one mouse embryo's heart tissue (modified with permission from reference [81]).*

basal respiration (**Figure 9e** and **f**). This is also associated with HF, shown by in utero echocardiography observation of poor cardiac contractility, low cardiac output, and severe pericardial effusion in the *Ohia* HLHS fetal mice [5]. In contrast, genetically identical *Ohia* mutants without CHD showed reduced basal respiration but entirely normal cardiac function (**Figure 9g** and **h**). Together these findings suggest intrinsic metabolic defects in patients with HLHS with a shared genetic etiology with their structural heart defects. These results are supported by studies demonstrating that mitochondrial metabolism [91] plays an important role in heart development and the regulation of cardiomyocyte differentiation [85]. These findings suggest systemic defects impact mitochondrial respiration in SV-CHD patients.
