Dietary nicotine: Won't mislead on passive smoking…: New insight into myocardial protection

Tuberculous pericarditis ED1TOR,-The case of tuberculous pericarditis presented by C P Clifford and G J Davies' contained a misleading characterisation of the findings on admission as classic tamponade.Kuss- maul's sign and an abnormal third heart sound are inconsistent with the physiology of classic tamponade.'Indeed, it is the virtual elimination of the rapid filling period necessary to produce a third heart sound that is a classic feature of tamponade.It is far more likely that this patient already had, under the tamponading fluid, an epicardial con- striction with its typically mixed picture; a pulsus paradoxus with a 20 mm Hg fall in blood pressure is unusual while a third heart sound and Kussmaul's sign are the rule in constriction.2Although acute tuberculous pericarditis can progress rapidly to acute or subacute constriction, this was not such a case.34Finally, I wish to argue against the term "peri- cardial knock."The abnormal early diastolic sound of constrictive pericarditis does not usually present an auscultatory knocking quality.More importantly, this description clouds concepts even if this form of the third heart sound did always "knock."The early diastolic sound of constrictive pericarditis is an especially early and often loud third heart sound with all necessary abnormal dynamics-accelerated early ventricular filling, with abrupt deceleration, into ventricles made abnormally stiffby pericardial scarring.'