  In the framework of the $N_f = 2+1$ flavor (axial)vector meson extended
Polyakov quark meson model we investigate the QCD phase diagram at finite
temperature and density. We use a $\chi^2$ minimization procedure to
parameterize the model based on tree\,-\,level decay widths and vacuum scalar
and pseudoscalar curvature masses which incorporate the contribution of the
constituent quarks. Using a hybrid approximation (mesons at tree level,
fermions at one\,-\,loop level) for the grand potential we determine the phase
boundary both on the $\mu_B-T$ and $\rho-T$ planes. We also determine the
location of the critical end point of the phase diagram. Moreover by
calculating the pressure and other thermodynamical quantities derived from it,
we determine a set of isentropic curves in the crossover region. We show that
the curves behave very similarly as their counterparts obtained from the
lattice in the crossover regime.
