Misare B D, Krukenkamp I B, Lazer Z P, Levitsky S
Department of Surgery, Harvard Medical School, Boston, MA.
Circulation. 1992 Nov;86(5 Suppl):II393-7.
Theoretically, the efficacy of continuous warm blood cardioplegia may be improved when administered retrogradely (RCWBC) rather than antegradely (ACWBC) in the setting of acute regional ischemia because of enhanced oxygen and substrate delivery to myocardial tissue distal to an acute coronary artery occlusion.
Eighteen Yorkshire swine were instrumented for quantification of global left ventricular systolic, diastolic, and regional left anterior descending coronary artery (LAD) zone mechanics before and after 10 minutes of mid-LAD occlusion, followed by 60 minutes of cardiac arrest using continuous warm blood cardioplegia. Initially, 20 ml/kg of 37 degrees C oxygenated blood cardioplegia (hematocrit, 22 +/- 0.6%) was infused antegradely, followed by maintenance of 75 ml/min ACWBC (n = 9) or 60-100 ml/min of RCWBC (n = 9). LAD occlusion was released 20 minutes after cardiac arrest (30 minutes total LAD ischemia), simulating surgical revascularization. Postischemic recovery of global preload recruitable stroke work was nearly complete with RCWBC but significantly depressed with ACWBC (84.9 +/- 9.5% versus 52.4 +/- 5.1%, respectively; p < 0.01). LAD regional stroke work was also well preserved postischemically with RCWBC but showed no functional recovery and systolic bulging after ACWBC (87.4 +/- 13.7% versus -11.36 +/- 7.46% of control values; p < 0.01). Global diastolic stiffness calculated using the beta-coefficient of an exponential end-diastolic pressure-versus-volume relation was unchanged with ACWBC but increased significantly after RCWBC (from 0.027 +/- 0.002 to 0.028 +/- 0.003 mm Hg/ml and from 0.028 +/- 0.003 to 0.036 +/- 0.004 mm Hg/ml, respectively).
These data suggest that with acute regional ischemia, both global and ischemic zone regional systolic function are depressed by ACWBC, whereas RCWBC affords adequate protection of contractile performance. However, a loss of diastolic compliance may result as a consequence of warm retrograde delivery.
从理论上讲，在急性局部缺血的情况下，逆行灌注持续温血心脏停搏液（RCWBC）可能比顺行灌注（ACWBC）更有效，因为这样能增强向急性冠状动脉闭塞远端心肌组织的氧和底物输送。
对18只约克夏猪进行仪器植入，以量化左心室整体收缩、舒张功能以及左前降支冠状动脉（LAD）区域的力学指标，在LAD中段闭塞10分钟前后进行测量，随后使用持续温血心脏停搏液使心脏停搏60分钟。最初，以20ml/kg的37℃氧合血心脏停搏液（血细胞比容，22±0.6%）顺行灌注，随后以75ml/min的速度进行ACWBC灌注（n = 9）或60 - 100ml/min的速度进行RCWBC灌注（n = 9）。心脏停搏20分钟后（LAD总缺血时间30分钟）解除LAD闭塞，模拟外科血管重建。RCWBC灌注后，整体预负荷可招募搏功的缺血后恢复几乎完全，但ACWBC灌注后明显降低（分别为84.9±9.5%和52.4±5.1%；p < 0.01）。LAD区域搏功在RCWBC灌注后缺血后也得到良好保存，但ACWBC灌注后无功能恢复且出现收缩期膨出（分别为对照值的87.4±13.7%和 - 11.36±7.46%；p < 0.01）。使用指数型舒张末期压力 - 容积关系的β系数计算的整体舒张硬度在ACWBC灌注后无变化，但在RCWBC灌注后显著增加（分别从0.027±0.002至0.028±0.003mmHg/ml和从0.028±0.003至0.036±0.004mmHg/ml）。
这些数据表明，在急性局部缺血时，ACWBC会使整体和缺血区区域的收缩功能降低，而RCWBC能为收缩性能提供充分保护。然而，逆行温血灌注可能导致舒张顺应性丧失。
