Heartbeat signal is an emerging biometric modality which is getting attention for its robustness against spoof attack. Introducing heartbeat into a fingerprint biometric system can yield promising results in two ways. First, it may increase the accuracy of the biometric system and second it may increase its robustness against spoof attacks. In this paper, a score level fusion is used based on the information content of the unimodal biometrics to enhance the information content of fingerprint biometrics. We measure the gain of information content of the multimodal biometric system obtained from fusion of fingerprint and heartbeat signal captured from fingers. Experimental results show that fusion of these two modalities increases the information content of the multimodal biometric system, consequently, increasing its accuracy and robustness against spoof attacks.