This document presents a literature review and comparative analysis of existing machine learning techniques used for heart disease prediction. It discusses several studies that have applied techniques like decision trees, naive Bayes, KNN, random forest, SVM and neural networks to heart disease datasets. The highest prediction accuracies reported range from 85-100%, with random forest and KNN performing best in some studies. The document aims to help researchers develop better heart disease prediction systems by understanding existing methodologies and identifying areas for improvement.