A medical closure device that is configured to be inserted into a patient's LAA (left atrial appendage) cavity comprises a closure member and at least one fixing member, wherein the closure member comprises a lid part and a body part one following the other in a proximal-distal direction. The lid part comprises a cover portion and a ring portion, the ring portion being configured to be circumferentially disposed along the rim of an individual LAA ostium, thus sealing the LAA ostium completely. The medical closure device is designed individually for each patient. A method of manufacturing the medical closure device includes the step of forming an LAA model based on computer graphic data of the patient. The LAA model is made by 3-D printing and is an exact reproduction of the patient's LAA. The medical closure device is then preformed using the LAA model.
