“…Several papers have reported the progression of acute idiopathic and acute viral pericarditis to constrictive pericarditis, and this is now widely accepted (Krook, 1954;Rabiner, Specter, Ripstein, and Schlecker, 1954;Connolly and Burchell, 1961;Robertson andArnold, 1962, 1965;Gibbons, Goldbloom, and Dobell, 1965;Harrold, 1968;Howard and Maier, 1968;Matthews, Cameron and George, 1970).…”