The clinical diagnosis of constrictive pericarditis

Sean Blake, M.D. Dublin, Ireland

Chronic constrictive pericarditis, being an uncom- mon disease, may present problems in diagnosis, especially in cases without pericardial calcification. Consequently, there is frequently a prolonged inter- val between the onset of symptoms and eventual diagnosis, and it is probable that the condition occasionally escapes diagnosis completely. The diag- nostic difficulties are of two types. At one level, the relative rarity of the disease leads to a lack of awareness on the part of the examiner. This is generally the main source of difficulty. Less fre- quently, there is an awareness of the possibility of constriction but there is difficulty in distinguishing it from restrictive cardiomyopathy. This differentia- tion can frequently be made by special techniques,1-3 but it may also be possible to do so by careful bedside examination. An analysis of a series of cases of constrictive pericarditis seen during the past 25 years directed attention to two clinical signs with a high level of specificity. These are precordial systolic retraction and a third sound accentuated by inspira- tion. The majority of previous publications have not referred to these signs; a minority have done so but in a cursory fashion .1,4 In one instance only has a frequency level been provided for one of the signs.5

Of a consecutive series of 34 cases of chronic constrictive pericarditis of a fibrotic or fibrocalcific type, 28 provided information on one or both of these signs. The value of the signs came to be appreciated only gradually so that both were not always assessed in earlier patients. Of the 28 patients, 17 had pericardial calcification on x-ray examination and in these the diagnosis presented little difficulty. Eleven patients lacked calcification and in these the mean interval between the onset of symptoms and final diagnosis was 3.4 years (11 years in one instance). Six patients had been diagnosed as definite cases of cardiomyopathy of unknown cause,

From the Department of Cardiology, Mater Misericordiae Hospital.

Received for publication Oct. 18, 1982; revision received Feb. 7, 1983; accepted March 7. 1983.

Reprint requests: Dr. Sean Blake, Dept. of Cardiology, Mater Misericor- diae Hospital, Dublin 7, Ireland.

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four as probable cases of coronary heart disease, and one, who had presented with massive edema during pregnancy, as a possible case of “renal edema.”

In all patients, as is usual in constriction, the cardiac impulse was relatively unobtrusive, con- trasting strikingly with an elevated jugular venous pressure. In 27 of the 28 the cardiac impulse was palpated with particular attention to the temporal relationship with ventricular systole. In all 27 there was no localized apex beat but rather a diffuse precordial movement which was frequently of slight amplitude but invariably constituted a systolic retraction.

An early third sound (pericardial knock) was audible in 27 patients and inaudible in one. In five of the 27 the effect of respiration on the intensity of the third sound was not noted. In the remaining 22 it was louder with inspiration in 17 (77 % ), louder with expiration in two (9%), and manifested no definite variation with respiration in three (14%). The pres- ence or absence of calcification did not affect these figures significantly.

The presence of both these signs is for practical purposes pathognomonic for constriction. Systolic retraction was found in 100% and a third heart sound accentuated by inspiration was found in 74% of those in whom the signs were assessed. In a consecutive series of five cases of restrictive cardio- myopathy observed during the past 10 years, neither sign was positive. The first of the five patients presented at a time when the specificity of the signs was still open to question. To avoid missing an operable condition, an exploratory thoracotomy was performed, but it demonstrated a normal pericardi- um. There have been no cases with positive signs where surgery subsequently failed to confirm a diagnosis of constriction. Likewise, it is unlikely that there have been cases where constriction was wrong- ly excluded through the absence of these signs, because in the patients where the diagnosis was based essentially on the relatively unequivocal find- ing of pericardial calcification, inspiratory accentua- tion of the third heart sound was usual (9 out of 12), and systolic retraction was invariable (16 out of 16).

Volume 106 Number 2

Most cases of restrictive cardiomyopathy (espe- cially those occurring in Western countries), involve the left ventricle,‘j and this was so in the five cases referred to here. It is therefore to be expected that a third heart sound would be accentuated by expira- tion. In the very rare instance of isolated right ventricular restrictive cardiomyopathy, a third heart sound might well be accentuated in inspiration. The rarity of such a condition excludes it as a practical problem in differential diagnosis from constrictive pericarditis, and there is no a priori reason to expect that there would be precordial systolic retraction.

It is not clear why the third sound of constrictive pericarditis should be louder in inspiration. It may be right ventricular in origin or possibly left ventric- ular but reflecting the paradoxical relationship between left ventricular filling and inspiration that is also exemplified by the pulsus paradoxus. As for the precordial retraction, it is likely that the thick-

Clinical diagnosis of constrictive pericarditis 433

ened rigid pericardium somehow restricts the systo- lic rotation that produces the normal apex beat. This would not be expected in a left ventricle affected by an infiltrative disorder. REFERENCES

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Hancock EW: Constrictive pericarditis: Clinical clues to diagnosis. JAMA 232:176, 1975. Horowitz MS, Rossen R, Harrison DC: Echocardiographic diagnosis of pericardial disease. AM HEART J 97:420, 1979. Moncada R, Baker M, Salinas M, Demos TC, Churchill R, Love L, Reynes C, Hale D, Carodso M, Pifarre R, Gunnar RM: Diagnostic role of computed tomography in pericardial heart disease: Congenital defects, thickening, neoplasms, and effusions. AM HEART J 103:263, 1982. Hirschmann JV: Pericardial constriction. AM HEART J 96:110, 1978. Boicourt OW, Nagle RE, Mounsey JPD: The clinical signifi- cance of systolic retraction of the apical impulse. Br Heart J 27:379, 1965. Wynne J, Braunwald E: The cardiomyopathies and myocar- ditides. In Braunwald E, editor: Heart disease: A textbook of cardiovascular medicine. Philadelphia, London, Toronto, 1980, WB Saunders Company, p 1460.