The present disclosure describes a device that can be implanted into the left atrial appendage for occlusion. The device can prevent or reduce thrombus formation in this anatomic region for patients with atrial fibrillation. This device includes a patient-specific inflatable device that represents a patient's anatomy or morphological class. The inflatable device can be designed by imaging (e.g., computed tomography, magnetic resonance imaging) the patient's anatomy. Through a catheter (or surgically), the inflatable device can be filled with an inflation fluid to occlude the appendage in a patient-specific fashion.