Digitalization have increasingly penetrated in healthcare. Generative artificial intelligence (AI) is a type of AI technology that can generate new content. Patients can use AI-powered chatbots to get medical information. Heart failure is a syndrome with high morbidity and mortality. Patients search about heart failure in many web sites commonly. This study aimed to assess Large Language Models (LLMs) -ChatGPT 3.5, GPT-4 and GPT-4.o- in terms of their accuracy in answering the questions about heart failure (HF). Thirteen questions regarding to the definition, causes, signs and symptoms, complications, treatment and lifestyle recommendations of the HF were evaluated. These questions to assess the knowledge and awareness of medical students about heart failure were taken from a previous study in literature. Of the students who participated in this study, 158 (58.7%) were first-year students, while 111 (41.3%) were sixth-year students and were taking their cardiology internship in their fourth year. The questions were entered in Turkish language and 2 cardiologists with over ten years of experience evaluated the responses generated by different models including GPT-3.5, GPT-4 and GPT-4.o. ChatGPT-3.5 yielded “correct” responses to 8/13 (61.5%) of the questions whereas, GPT-4 yielded “correct” responses to 11/13 (84.6%) of the questions. All of the responses of GPT-4.o were accurate and complete. Performance of medical students did not include 100% correct answers for any question. This study revealed that performance of GPT-4.o was superior to GPT-3.5, but similar with GPT-4