1. Department of Cardiology, Essex Cardiothoracic Centre, Basildon, United Kingdom (K.K., T.R.K., J.R.D., R.A.G., K.H.T., O.A., P.A.K., G.J.C., G.V.K.).
2. School of Medicine, Anglia Ruskin University, United Kingdom (K.K., T.R.K., O.A., G.J.C., G.V.K.).