Marked discordance between dynamic and passive diastolic pressure-volume relations in idiopathic hypertrophic cardiomyopathy.
Marked discordance between dynamic and passive diastolic pressure-volume relations in idiopathic hypertrophic cardiomyopathy.
复制标题
特发性肥厚型心肌病的动态和被动舒张压-容积关系之间存在显着不一致。
DOI：
10.1161/01.cir.94.1.52
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发表时间：
1996
期刊：
影响因子：
37.8
通讯作者：
Kass,DA
中科院分区：
文献类型：
--
作者：
Pak,PH;Maughan,L;Baughman,KL;Kass,DA
背景：特发性肥厚性心肌病（HCM）患者在充盈（PVRfill）期间测量的动态舒张压-容积曲线通常比假设高腔刚度时预期的要浅得多。我们假设这些曲线明显偏离被动舒张末期压力-容积关系（EDPVR），并探讨了这种不一致的机制。方法与结果采用有创压力-容积分析和导管方法对42例患者进行研究。9例HCM，其余患者分为3个对照组：11例左室（LV）功能正常，13例左室肥厚继发于慢性高血压（LVH-HTN）， 9例特发性扩张型心肌病（DCM）。记录球囊导管阻塞下腔静脉流入时的EDPVRs。在正常受试者、LVH-HTN患者和DCM患者中，pvrfill曲线仅略微偏离被动EDPVR。与之形成鲜明对比的是，HCM患者显示平坦的pvr填充，这与陡峭的EDPVR非常不同。在减少预负荷时，HCM患者的pvrfill关系平行向下移动，在相同的腔室容积下，净压力下降为- 10±4 mm Hg。其他患者组的这种阶梯状移动要小得多（- 2±2 mm Hg；P<.001）。HCM的异常行为不能直接归因于黏度增加、心包约束增强或等容松弛的预负荷依赖性。松驰的区域异质性可能起作用；然而，我们推测主要机制与HCM独特的纤维和室结构有关，可能与心室相互作用增强有关。结论HCM的左室充注压力升高不仅仅是由于腔体僵硬，还反映了随腔体负荷变化的偏置压力的主要影响。充盈期间平坦的压力-容积关系和舒张末期陡峭的关系之间的巨大差异似乎是HCM独有的。这表明在解释由稳态数据得出的刚度结果时应谨慎使用，并表明改变腔体几何形状和/或减少相互作用的治疗可能显著影响HCM的左室舒张压。
BackgroundDynamic diastolic pressure-volume curves measured during filling (PVRfill) in patients with idiopathic hypertrophic cardiomyopathy (HCM) are often considerably shallower than would be anticipated if one assumed high chamber stiffness. We hypothesized that these curves deviate markedly from the passive end-diastolic pressure-volume relation (EDPVR) and explored the mechanisms for such a discordance.Methods and ResultsWe used invasive pressure-volume analysis and conductance catheter methodology to study 42 patients. Nine had HCM, and the remaining patients comprised three comparison groups: 11 with normal left ventricular (LV) function, 13 with LV hypertrophy secondary to chronic hypertension (LVH-HTN), and 9 with idiopathic dilated cardiomyopathy (DCM). EDPVRs were recorded during balloon catheter obstruction of inferior vena cava inflow. In normal subjects, LVH-HTN patients, and DCM patients, PVRfillcurves deviated only slightly from the passive EDPVR. In striking contrast, HCM patients displayed a flat PVRfillthat was very different from the steep EDPVR. On reduction of preload, PVRfillrelations in HCM shifted downward in parallel, with a net pressure decline at the same chamber volume of −10±4 mm Hg. This staircaselike shift was much less in the other patient groups (−2±2 mm Hg;P<.001). The unusual behavior in HCM could not be attributed directly to increased viscosity, enhanced pericardial constraint, or preload dependence of isovolumic relaxation. Regional heterogeneity of relaxation may play a role; however, we speculate that the major mechanism relates to the unique fiber and chamber architecture seen with HCM and possibly to enhanced ventricular interaction.ConclusionsElevated LV filling pressures in HCM are not due simply to a stiff cavity but also reflect a major influence of offset pressures that vary with chamber loading. The large disparity between flat pressure-volume relations during filling and steep end-diastolic relations appears unique to HCM. This indicates that caution should be used in the interpretation of stiffness results derived from steady-state data and suggests that therapies that alter cavity geometry and/or reduce interaction may markedly influence LV diastolic pressures in HCM.