Compressive cardiac and circulatory disorders: Clinical and laboratory correlation

Abstract

Forty patients with primary cardiac compression due to constrictive pericarditis, lax effusion, or cardiac tamponade were studied. An additional 28 patients were presented with spurious evidence of cardiac compression or with pericardial effusion that plays an unimportant role in the circulatory disorder. Rather stringently defined physical findings were sought which might allow discrimination between cardiac disorders. Certain procedures which alter circulatory variables were carried out. The following conclusions are drawn from the results. 1. 1. Constrictive pericarditis is associated with venous and auscultatory phenomena which do not allow separation from other forms of heart disease causing congestive heart failure. Kussmaul's venous sign is present in less than 40 per cent, an x descent is inconstant; pulsus paradoxus, as classically defined, is not observed. Right and left heart filling pressures do not differ greatly and, when varied, retain similarity. Cardiac performance appears independent of wide ranges of venous pressure. 2. 2. In lax pericardial effusion, Kussmaul's sign and Friedreich's sign, along with third heart sounds, are not present. At times, a prominent x descent is seen in venous pressure recordings. Pulsus paradoxus is inconstant with tranquil breathing but is regularly induced by deep inspiration. There is inspiratory decrease in venous pressure and pericardial pressure. Cardiac index is normal and venous pressure is less than 12 mm. Hg. Circulatory distress is not apparent and removal of fluid from the pericardium has little effect on cardiac performance. Tamponade induces signs of circulatory distress and is regularly characterized by pulsus paradoxus and there is frequently a prominent systolic drop in venous pressure (x descent). Friedreich's sign, a third heart sound, and Kussmaul's venous sign, are absent. The venous pressure exceeds 12 mm. Hg. There is an inspiratory decrease in venous pressure and pericardial pressure. The low cardiac index is usually relieved by tap. When aortic stenosis is present, respiratory variation in left ventricular systolic pressure may not be reflected by clinical pulsus paradoxus. 3. 3. Spurious signs of cardiac compression may be due to: (1) respiratory disease, (2) severe myocardial disease and incidental effusion or, (3) obesity. In the first case, there is pulsus paradoxus, normal cardiac index, low venous pressure, and venous and pericardial pressure decrease with inspiration. The second group does not show pulsus paradoxus and the elevated venous pressure, diastolic dip, and third heart sounds are due to heart failure. Obesity may cause pulsus paradoxus and increased peripheral venous pressure, which does not reflect central venous pressure. These findings seem related to inspiratory collapse of extrathoracic vessels, since they are influenced by changes in blood volume or venous tone.