Abstract 15737: Impairment of Myocardial Perfusion Correlates With Heart Failure Progression in Patients With Noncompaction Cardiomyopathy.

Introduction: Noncompaction cardiomyopathy (NCC) is a congenital heart disease characterized by an arrest of the myocardial compaction process. Although NCC patients have impaired formation of microvasculature, the functional impact of these changes remains undefined. Hypothesis: We sought to analyze a potential correlation between myocardial ischemia and heart failure progression in patients with NCC. Methods: We enrolled 20 (12 male, 8 female) patients with NCC, diagnosed by cardiac MRI. The average age was 46±15.3 years. Echocardiography was performed to determine left ventricular end diastolic diameter and volume (EDD and EDV), ejection fraction (LVEF), with global longitudinal strain (GLS) postprocessing. At patient inclusion we also measured serum levels of NT-proBNP. Myocardial SPECT was performed at rest and on stress, determining summed difference score (SDS). Significant myocardial ischemia was defined as SDS≥2. Results: Of 20 patients enrolled, 9 patients (45%) had evidence of myocardial ischemia (Group A), 11 patients (55%) showed no significant ischemic changes (Group B). The two groups did not differ in sex (male 67% in Group A vs. 55% in Group B, P=0.58), age (45±14,6 years vs. 46±14,6 years, P=0.92), creatinine (79±14 μmol/L vs. 74±12 μmol/L, P=0.48) or bilirubin (12±7 μmol/L vs. 11±3 μmol/L, P=0.51). When compared to Group B, Group A had significantly higher EDD (6.3±0.9 cm vs. 5.3±0.6 cm, P=0.018), lower NTproBNP levels (1950±2004 pg/mL vs. 294±429 pg/mL in Group B, P=0.02) and a tendency toward lower LVEF (36.6±16.7% vs. 51.8±16.8% in Group B, P=0.06), higher EDV (179.2±53.9 mL vs. 138.7±47.4 mL, P=0.09), and lower GLS (-11.4±7% vs. -15.4±4%, P=0.12). Overall, higher SDS was associated with lower LVEF (r=-0.46, P=0.04), higher EDV (r=0.53, P=0.02), higher levels of NT-proBNP (r=0,82, P<0.001), and a tendency toward lower GLS (r=0.40, P=0.06). Conclusions: In patients with NCC, the presence of myocardial ischemia is associated with worse left ventricular function, dilation of left ventricle and more pronounced neurohumoral activation. Further studies are needed to investigate whether treatment approaches targeting myocardial ischemia, such as CD34+ cell therapy, may halt the progression of disease in this patient cohort. [ABSTRACT FROM AUTHOR]