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BRIEF REPORTS
pericardial fistula because of carcinomatous erosion of the pericardial cavity; in only 3 cases has this mechanism been demonstrated.6 A valve mechanism between the bronchial tree and the pericardium may allow continued inflation of the pericardial sac without significant deflation and consequent cardiovascular compromise, as occurred in our patient.3 The pneumopericardium alone in the absence of tension does not usually produce symptoms. On frontal arid lateral chest roentgenograms, the heart is partially or completely surrounded by air extending up to the anatomic level of the pericardial reflection. Although air in the pericardium will shift according to the patient’s position, when the patient is upright there Will be more air in the left side of the pericardium because this space is more extensive than the right, where the pericardium is anchored by its reflections onto the superior and inferior caval veins. Pneumopericardium and a small heart should alert the physician to the presence of cardiac tamponade, as occurred in a patient with the “small heart sign.‘17The relatively small heart in this situation is presumably due to cardiac compression and low cardiac output. The incidence of tamponade due to pneumopericardium has been found to be up to 37%. Initially, it
was thought that air introduced into the pericardium was innocuous, but later studies showed that both the amount of gas and the rate of instillation are major factors in the production of tamp0nade.l Neonates and adults with pneumopericardium who are being mechanically ventilated are prone to rapid deterioration. Pericardial drainage by a tube should be maintained until mechanical ventilation is discontinued. When there is evidence of cardiac tamponade, immediate aspiration is required. In conclusion, the plain chest roentgenogram is the primary tool for diagnosing pneumopericardium. The presence of a small heart suggests cardiac tamponade. If Swan-Ganz findings confirm tamponade, intervention should be undertaken immediately. 1. Cummings RG, Wesly RLR, Adams DH, Lowe JE. Pneumopericardium resulting in cardiac tamponade. Ann Thorac Surg 1384;37:511-518. 2. Lynn RB. Delayed post-traumatic pneumopericardium producing acute cardiac tamponode. Can r Surg 1983;26:62. 3. Damp MH, Angorn IB. Air tamponade. S Afr Med 1 1984;66:416-417. 4. Baydur A, Gottlieb LS. Pneumopericardium and pneumothorax complicating bronchogenic carcinoma. West 1 Med 1976;124:144-146. 5. Harris RD, Kostiner AI. Pneumopericardium associated with bronchogenic carcinoma. Chest 1975;67:115-116, 6. Reeve TS. Pyopneumopericardium: report of a case. Med r Aust 13%; 2:376-378. 7. Cimmino CV. Some radio-diagnostic notes on pneumomediastinum, pneu-
mothorax, and pneumopericardium. Va Med Monthly 1367;34:205-212.
pulmonary vascular disease was an important determinant of symptoms in patients with mitral stenosis. This study contains numerous p and r values and thus WILLIAM C. ROBERTS, MD has the best statistics appearing in the AJC during its first 5 years of publication. he AJC in December 1962 contained 21 articles, ocThe 8 case reports included patients with the folcupying 127 pages, including 11 clinical studies, 1 ex- lowing conditions: left-sided hemodynamic studies perimental s‘tudy, 1 historic study and 8 case reports. during intermittent left bundle branch block2; cardiThis piece mentions 9 articles. ac sarcoidosis causing ventricular tachycardia3; right The lead article was by Hugenholtz and associates* ventricular sarcoma operatively successfully excised4; from Boston, Massachusetts, and it correlated clinical complete atrioventricular heart block due to gumma of symptoms to hemodynamic observations in 44 patients the ventricular septum5; carcinoma of the lung metawith mitral stenosis with or without mild mitral regur- static to the heart and electrocardiographically simugitation and without aortic valve dysfunction. Of the 44 lating left atria1 infarctio&; atria1 flutter in myotonic patients, 6 were asymptomatic (class I]; 20 had no’ dystrophy7; hemodynamic studies in progressive mussymptoms during their usual activities but were symp- cular dystrophy? and partial anomalous pulmonary tomatic on unusual exertion (class II); and 18 had se- venous drainage with intact atria1 septum in mitral vere limitation of activities and dyspnea after minimal stenosis.g exertion (class III). None of the 44 patients had overt 1. Hugenholtz PG. Ryan TJ, Stein SW, Abelmann WH. The spectrum of pure congestive heart failure. Inverse relations w&-e found mitrai stenosis. Hemodynamic studies in relation to clinical disability. Am r betwe& both left atria1 and pulmonary arterial pres- CardioJ 1962;10:773-784. sures and mitral valve area and between left atrial-left 2. Bourassa MC, Boiteau GM, Allenstein BJ. Hemodynamic studies during ventricular mean diastolic pressure gradient and mi- intermittent left bundle branch block. Am [ CordioJ 1962;10:792-799. 3. Stein HM, Gross JM, Shulman H. A case of cardiac sarcoidosis manifested tral valve area. Cardiac index and mitral valve area by uncontrollable ventricular tochycardia. Review of cardiac manifestations also ha’d a positive relation. Mitral valve areas <1.5 in sixteen cases of sarcoidosis. Am J CardioJ 1962:10:864-870. cm2 were present in all 18 patients in functional class 4. Dong E Jr, Hurley EJ, Shumway NE. Primary cardiac sarcoma. Am [ 1962;10:871-878. III and 17 (65%) of the 26 patients in functional classes CardioJ 5. Ramamoorthy K, Sahiar KH, Golwalla AF. Complete atrioventricular heart I and II. Cardiac output (2.8 liters/min/m2], left atria1 block due to gamma of the interventricular septum. Am [ CardioJ 1962;10:879881. mean pressure (18 and 19 mm Hg) and mean diastolic 6. Rothfeld EL, Zirkin RM. UnusuoJ electrocardiographic evidence of metapressure gradient (11 and 13 mm Hg) were similar static cardiac tumor resembling atrial infarction. Am 1 Cardiol 1962;10:882between the 26 patients in classes I and II and the 18 885. 7. Spurny OM, Wolf JW. Prolonged atrial flutter in myotonic dystrophy. Am J patients in class III. In comparison to the class I and II CardioJ 1962;10:886-889. patients, however, the class III patients had higher 8. Rubeiz GA, Saab NG. Hemodynamic study in a case of progressive muscumean pulmonary arterial pressure (36 vs 22 mm Hg] Jar dystrophy involving the heart. Am J Cardiol 1962;10:890-893. Wassermil M, Hoffman MS. Partial anomalous pulmonary venous drainage and higher pulmonary arteriolar resistance (425 vs 105 9. associated with mitral stenosis with an intact atrial septum. A distinctive dynes s cm+), a finding suggesting that the degree of hemodynamic syndrome. Am J CordioJ 1962;10:894-899.
The AJCin December 1962
T