Jones J W, Izzat N N, Rashad M N, Thornby J I, McLean T R, Svensson L G, Beall A C
Cora and Webb Mading Department of Surgery, Baylor College of Medicine, Houston, Texas.
Ann Thorac Surg. 1992 Jul;54(1):44-9. doi: 10.1016/0003-4975(92)91138-y.
Early diagnosis of postoperative cardiac tamponade is impeded by its clinical similarity to left ventricular failure. Moreover, the hemodynamic changes necessary to diagnose cardiac tamponade are detected by conventional monitoring technique only after clinical compromise. Early signs of cardiac tamponade and left ventricular failure were studied with emphasis on right ventricular function in anesthetized dogs. One group (n = 20) had cardiac tamponade produced by incrementally increasing pericardial pressure (2 to 20 mm Hg), and another group (n = 20) had acute left ventricular failure produced by successive ligation of the anterior descending coronary artery at the lower, middle, and upper thirds. Besides standard hemodynamic measurements, right ventricular function was examined with a rapid-response thermodilution catheter. During cardiac tamponade, cardiac output, right ventricular ejection fraction, right ventricular stroke volume, and right ventricular end-diastolic volume were significantly decreased from baseline values after a pericardial pressure of 8 mm Hg or more (p less than 0.05). Right atrial and pulmonary arterial pressures were not significantly elevated until 14 and 20 mm Hg of pericardial pressure, respectively. Although cardiac function in the left ventricular failure group was reduced after each ligation, right ventricular ejection fraction remained unchanged. This study suggests that right ventricular indices may facilitate earlier diagnosis of cardiac tamponade with greater accuracy.
术后心脏压塞的早期诊断因与左心室衰竭在临床上相似而受到阻碍。此外，诊断心脏压塞所需的血流动力学变化仅在出现临床失代偿后才能通过传统监测技术检测到。在麻醉犬身上研究了心脏压塞和左心室衰竭的早期体征，重点关注右心室功能。一组（n = 20）通过逐渐增加心包压力（2至20毫米汞柱）造成心脏压塞，另一组（n = 20）通过在冠状动脉前降支的下、中、上三分之一处连续结扎造成急性左心室衰竭。除了标准的血流动力学测量外，还使用快速响应热稀释导管检查右心室功能。在心脏压塞期间，当心包压力达到8毫米汞柱或更高时，心输出量、右心室射血分数、右心室搏出量和右心室舒张末期容积与基线值相比显著降低（p < 0.05）。右心房和肺动脉压力分别在心包压力达到14和20毫米汞柱时才显著升高。虽然左心室衰竭组在每次结扎后心脏功能均降低，但右心室射血分数保持不变。这项研究表明，右心室指标可能有助于更准确地早期诊断心脏压塞。
