  In this article, we extend our previous work to study the $\Sigma$-type heavy
baryons $\Sigma_c$ and $\Sigma_b$ in the nuclear matter using the QCD sum
rules, and obtain three coupled QCD sum rules for the masses $M_{\Sigma_Q}^*$,
vector self-energies $\Sigma_v$ and pole residues $\lambda^*_{\Sigma_Q}$ in the
nuclear matter. Then we take into account the effects of the unequal pole
residues from different spinor structures, and normalize the masses from the
QCD sum rules in the vacuum to the experimental data, and obtain the
mass-shifts $\delta M_{\Sigma_c}=-123\,\rm{MeV}$ and $\delta
M_{\Sigma_b}=-375\,\rm{MeV}$ in the nuclear matter.
