Inagaki S, Sugihara H, Nakagawa T, Katahira T, Kubota Y, Katsume H, Adachi H, Nakagawa M, Ikegaya K, Matsui S
Kaku Igaku. 1989 Feb;26(2):177-87.
Pressure-volume (PV) loop is of great value for the assessment of left ventricular (LV) function, but its clinical application has been limited by methodological complexity. A new system was developed to make accurate loop with simplified procedure, and was applied to clinical and interventional study. The system constitutes of a mobile gamma camera, a poly-amplifier and a data processor (GMS-550U, Toshiba Medical) installed in cardiac catheterization labo for simultaneous raw data handling and successive analysis. Since LV time activity curve (TAC) obtained by usual ECG gating is not fully reliable for a entire cardiac cycle, radionuclide data acquired in list mode was formatted forward and backward from ECG trigger together with analog data of LV pressure, ECG and PCG. PV loops were drawn in 10 patients (OMI, AP, MR, HCM) and 5 normals before and after infusion of angiotensin-II (AII), and Emax and LV work (systolic; SW, diastolic; DW, net; NW = SW - DW) were measured. Radionuclide ventriculography was safely performed with cardiac catheterization even in patients with congestive heart failure. Satisfactory PV loops were obtained by the advantage of simultaneous acquisition of RNV and analog data. Changes of ECG, PCG, volume, pressure and derived indices through one cardiac cycle were readily comparable each other. Peak LV pressure (mmHg) increased from 134 to 159 and then 182 by infusion of AII, but no change in heart rate was observed Emax was higher in normals and AP (mean 1.96 mmHg/ml/m2) than in OMI and MR (range of 0.85-1.36). SW increased in response to rise of LV pressure in all subjects. NW increased in normals and AP, but decreased in OMI and MR with relative increase in DW. In conclusion, this new system is feasible for repetitive studies under drug intervention, since it makes accurate PV loop under physiologic state, i.e. without pacing and volume overloading. Variable changes of SW, DW, and NW in response to afterloading were clarified, which may be useful for the evaluation of cardiac reserve in normal and diseased heart.
压力-容积（PV）环对于评估左心室（LV）功能具有重要价值，但其临床应用一直受到方法复杂性的限制。开发了一种新系统，可通过简化程序绘制精确的环，并应用于临床和介入研究。该系统由一台移动γ相机、一个多放大器和一个数据处理器（GMS-550U，东芝医疗）组成，安装在心脏导管实验室中，用于同时处理原始数据和进行连续分析。由于通过常规心电图门控获得的左心室时间-活性曲线（TAC）在整个心动周期中并不完全可靠，因此以列表模式采集的放射性核素数据与左心室压力、心电图和心音图的模拟数据一起从心电图触发点向前和向后进行格式化。在10例患者（心肌梗死、主动脉瓣关闭不全、二尖瓣反流、肥厚型心肌病）和5例正常受试者中，在输注血管紧张素-II（AII）前后绘制PV环，并测量Emax和左心室作功（收缩期；SW，舒张期；DW，净功；NW = SW - DW）。即使在充血性心力衰竭患者中，放射性核素心室造影也能与心脏导管检查安全地同时进行。通过同时采集放射性核素心室造影（RNV）和模拟数据的优势，获得了令人满意的PV环。一个心动周期中心电图、心音图、容积、压力和派生指标的变化很容易相互比较。输注AII后，左心室峰值压力（mmHg）从134升高至159，然后升至182，但心率未观察到变化。正常人和主动脉瓣关闭不全患者的Emax较高（平均1.96 mmHg/ml/m2），高于心肌梗死和二尖瓣反流患者（范围为0.85 - 1.36）。所有受试者的SW均随左心室压力升高而增加。正常人和主动脉瓣关闭不全患者的NW增加，而心肌梗死和二尖瓣反流患者的NW减少，DW相对增加。总之，这种新系统对于药物干预下的重复性研究是可行的，因为它能在生理状态下（即无需起搏和容量超负荷）绘制精确的PV环。明确了SW、DW和NW对后负荷变化的不同反应，这可能有助于评估正常和患病心脏的心脏储备。
