用于急性缺血性右心室衰竭的改良格林分流术可逆转继发性左心室功能障碍。
Modified Glenn connection for acutely ischemic right ventricular failure reverses secondary left ventricular dysfunction.
作者信息
Danton M H, Byrne J G, Flores K Q, Hsin M, Martin J S, Laurence R G, Cohn L H, Aklog L
机构信息
Department of Cardiac Surgery, Brigham and Women's Hospital/Harvard Medical School, Boston, MA, USA.
出版信息
J Thorac Cardiovasc Surg. 2001 Jul;122(1):80-91. doi: 10.1067/mtc.2001.114632.
BACKGROUND
Right heart failure after cardiopulmonary bypass can result in severe hemodynamic compromise with high mortality, but the underlying mechanisms remain poorly understood. After ischemia-induced right ventricular failure, alterations in the interventricular septal position decrease left ventricular compliance and limit filling but may also distort left ventricular geometry and compromise contractility and relaxation. This study investigated the effect of acute isolated right ventricular ischemia on biventricular performance and interaction and the response of subsequent right ventricular unloading by use of a modified Glenn shunt.
METHODS
In 8 pigs isolated right ventricular ischemic failure was induced by means of selective coronary ligation. A modified Glenn circuit was then established by a superior vena cava-pulmonary artery connection. Ventricular performance was determined by conductance catheter-derived right ventricular pressure-volume loops and left ventricular pressure-segment length loops. Hemodynamic data at baseline, after right ventricular ischemia, and after institution of the Glenn circuit were obtained during inflow occlusion, and the load-independent contractile indices were derived.
RESULTS
Right ventricular free-wall ischemia resulted in acute right ventricular dilation (118 +/- 81 mL vs 169 +/- 70 mL, P =.0008) and impairment of left ventricular contractility indicated by the reduced end-systolic pressure-volume relation slope (50.0 +/- 19 mm Hg/mm vs 18.9 +/- 8 mm Hg/mm, P =.002) and preload recruitable stroke work index slope (69.6 +/- 26 erg x cm(-3) x 10(3) vs 39.7 +/- 13 erg x cm(-3) x 10(3), P =.003). In addition, left ventricular relaxation (tau) was significantly prolonged (33.3 +/- 10 ms vs 53.0 +/- 16 ms, P =.012). Right ventricular unloading with the Glenn shunt reduced right ventricular dilation and significantly improved left ventricular contraction, end-systolic pressure-volume relation slope (18.9 +/- 8 mm Hg/mm vs 35.8 +/- 18 mm Hg/mm, P =.002), preload recruitable stroke work index slope (39.7 +/- 26 erg x cm(-3) x 10(3) vs 63.0 +/- 22 erg x cm(-3) x 10(3), P =.003), and diastolic performance (tau 53.0 +/- 16 ms vs 43.5 +/- 13 ms, P =.001).
CONCLUSIONS
Right ventricular ischemia-induced dilation resulted in acute impairment of left ventricular contractility and relaxation. A modified Glenn shunt attenuated the left ventricular dysfunction by limiting right ventricular dilation and restoring left ventricular cavity geometry.
背景
体外循环后右心衰竭可导致严重的血流动力学损害，死亡率高，但其潜在机制仍知之甚少。缺血性右心室衰竭后，室间隔位置的改变会降低左心室顺应性并限制充盈，但也可能使左心室几何形状变形，损害收缩性和舒张功能。本研究通过使用改良的格林分流术，研究急性孤立性右心室缺血对双心室功能及相互作用的影响，以及随后右心室卸载的反应。
方法
在8头猪中，通过选择性冠状动脉结扎诱导孤立性右心室缺血性衰竭。然后通过上腔静脉-肺动脉连接建立改良的格林循环。通过电导导管获得的右心室压力-容积环和左心室压力-节段长度环来测定心室功能。在基线、右心室缺血后和建立格林循环后，在流入道闭塞期间获取血流动力学数据，并得出与负荷无关的收缩指数。
结果
右心室游离壁缺血导致急性右心室扩张（118±81 mL对169±70 mL，P = 0.0008），左心室收缩功能受损，表现为收缩末期压力-容积关系斜率降低（50.0±19 mmHg/mm对18.9±8 mmHg/mm，P = 0.002）和可招募前负荷搏功指数斜率降低（69.6±26 erg·cm⁻³×10³对39.7±13 erg·cm⁻³×10³，P = 0.003）。此外，左心室舒张期（τ）显著延长（33.3±10 ms对53.0±16 ms，P = 0.012）。格林分流术进行右心室卸载可减少右心室扩张，并显著改善左心室收缩功能、收缩末期压力-容积关系斜率（18.9±8 mmHg/mm对35.8±18 mmHg/mm，P = 0.002）、可招募前负荷搏功指数斜率（39.7±26 erg·cm⁻³×10³对63.0±22 erg·cm⁻³×10³，P = 0.003）和舒张期功能（τ 53.0±16 ms对43.5±13 ms，P = 0.001）。
结论
右心室缺血性扩张导致左心室收缩和舒张功能急性受损。改良的格林分流术通过限制右心室扩张和恢复左心室腔几何形状减轻了左心室功能障碍。
Zotero 插件