Institute of Cardiovascular and Medical Sciences, British Heart Foundation Glasgow Cardiovascular Research Centre (M.M.Y.L., K.J.M.B., K.M., G.R., R.T.C., C.B., L.C., K.F.D., N.N.L., C.J.P., J.R.P., P.W., A.R., P.B.M., J.J.V.M., P.S.J., M.C.P., N.S.), University of Glasgow, United Kingdom. Queen Elizabeth University Hospital, Glasgow, United Kingdom (M.M.Y.L., K.M., G.R., R.T.C., C.B., K.F.D., N.N.L., R.W., P.B.M., J.J.V.M., P.S.J.). Glasgow Royal Infirmary, United Kingdom (M.M.Y.L., G.R., J.R.P., M.C.P., N.S.). Robertson Centre for Biostatistics (K.W., A.M.), University of Glasgow, United Kingdom. Golden Jubilee National Hospital, Glasgow, United Kingdom (R.T.C., C.B., J.G.D., M.C.P.). University Hospital Crosshouse, Kilmarnock, United Kingdom (V.C.). Forth Valley Royal Hospital, Larbert, United Kingdom (C.L.). University Hospital Ayr, United Kingdom (V.L.). Royal Alexandra Hospital, Paisley, United Kingdom (C.L.M.). University Hospital Monklands, Airdrie, United Kingdom (C.J.P.). West Glasgow Ambulatory Care Hospital, United Kingdom (I.A.S.). University of Sheffield, United Kingdom (S.S.).