1 Second Propaedeutic Department of Internal Medicine, Aristotle University of Thessaloniki, General Hospital "Hippokration", Greece.
2 Third Department of Cardiology, Aristotle University of Thessaloniki, General Hospital "Hippokration", Greece.
3 Second Department of Cardiology, Aristotle University of Thessaloniki, General Hospital "Hippokration", Greece.
4 Second Propaedeutic Department of Internal Medicine, Aristotle University of Thessaloniki, General Hospital "Hippokration", Greece; Veterans Affairs Medical Center, George Washington University, Washington, District of Columbia.