This is about my granny,two days ago,right in the mid night she experienced a thud like sound in her heart and told that she suffocates for a little while after that. Can somebody tell me why is that? What could possibly be the Sound and why was it cause d? She experienced a slight pain in the right side of her chest in the morning. From past two days she was walking on the treadmill at a speed 1.8 or 2 as told by the doctor to workout due to her constantly increasing weigh from past 11month since the time she has started taking insulin doses. She has been not at all well from past 11months.