FGFR2 and hypertrophic cardiomyopathy: In contrast to the adverse effects of loss of Fgfr1 and Fgfr2, continuously induced expression of a constitutively active FGFR1 in cardiomyocytes resulted in increased contractility within 1 day, and after seven days, hypertrophic cardiomyopathy, left ventricular outflow tract obstruction, diastolic dysfunction and heart failure (28).