Fill in the Blanks insuficiencia cardiacaOnline version corazopn venahdsuiad by Juan Sebastian Padilla mendoza 1 ventricles blood However efficiently muscle heart dilate Heart failure usually occurs after other conditions have damaged or weakened the . , the heart does not have to be weakened to cause heart failure . This can also happen if the heart becomes too stiff . In heart failure , the heart's main pumping chambers ( ) can become stiff and not fill properly between beats . In some cases of heart failure , the heart can become damaged and weak , and the ventricles stretch ( ) to the point where the heart cannot pump throughout the body .