C4A and heart failure: Following one-time systemic injection of the AAV9-based viral vector, the decoy oligonucleotide is specifically expressed by cardiomyocytes as a shRNA bearing the consensus binding site of NFATc1-c4, which potently down-regulates expression of NFAT-dependent pro-hypertrophic genes, hence preventing or inhibiting TAC-induced cardiac hypertrophy and subsequent heart failure.