Heikki V. Huikuri mainly focuses on Internal medicine, Cardiology, Heart rate, Heart rate variability and Myocardial infarction. His Internal medicine study frequently links to other fields, such as Endocrinology. The study incorporates disciplines such as Surgery and Risk factor in addition to Cardiology.

The various areas that Heikki V. Huikuri examines in his Heart rate study include Anesthesia, Physical therapy, Physical exercise and Approximate entropy. His Heart rate variability study which covers Exercise physiology that intersects with Endurance training. His Myocardial infarction research includes themes of T wave alternans, Ventricular tachycardia and Ejection fraction.