Mean curvature and compactification of surfaces in a negatively curved   Cartan-Hadamard manifold
  We state and prove a Chern-Osserman-type inequality in terms of the volume growth for complete surfaces with controlled mean curvature properly immersed in a Cartan-Hadamard manifold $N$ with sectional curvatures bounded from above by a negative quantity $K_{N}\leq b<0$ 
Antonio Esteve and Vicente Palmer
math.DG