心疾患における心血管内圧の一次微分の臨床応用

Studies on the First Derivatives of Cardiovascular Pressure Pulse in Heart Diseases; Clinical Application

緒言

　心室内圧の一次微分すなわち速度脈波（dp／dt）の大きさは心筋収縮力を示す一つのparameterと考えられ，種々の薬物，静脈還流，拡張終期心室内圧および容量，血圧などの心筋収縮力に及ぼす影響を検討する場合，しばしば用いられている（Reevesら^1），Nealら^2），Gle—asonら^3），Wallaceら^4），Schaperら^5））。また末梢動脈のdp／dtから左室流出路障害の鑑別をする試みもなされている（Masonら^6））。

　dp／dtの大きさはもちろん心血管内圧の原波形の傾斜から作図的に近似値を算出しうるが^7），操作が煩雑であり，またdp／dtの変動を連続的に観察しようとする場合にも不利である。血圧測定用preampとD．　C．　ampの間にFig．　1に示したような微分回路（CR回路）を挿入することにより，dp／dt波形が連続的に記録でき，観察にきわめて便利である。われわれは心臓カテーテル検査または心臓血管造影検査時に，心血管内圧と同時に一次微分波形を記録して種々の知見を得たので，微分回路の原理，装置および方法，微分波形のpattern，血行動態との関係を述べる。

The first derivatives of intracardiovascular pressure pulse were recorded at routine car-diac catheterization and angiocardiography in the Department of Thoracic Surgery of Tokyo University. The recording apparatus, method, theoretical considerations and he-modynamic implication of the first derivative curves were discussed. The results obtainedare summarized as follows ;

1) Although there is the positive correla-tion between the right ventricular systolic pressure and the maximal rise of pressure pulse (peak dp/dt), the various patterns of the first derivative curves in the same level of right ventricular systolic pressure were recorded according to hemodynamic states.

2) There is also the positive correlation between the pressure pulse of peripheral artery and its peak dp/dt, but the severity of aortic insufficiency assessed by angiocar-diography seems better reflected in the inc-rease of peak dp/dt than the mere widening of pulse pressure.

3) The changes of dp/dt in various con-ditions, such as changes of heart rate, exer-cise, corrective or replacement surgery, and catecholamine administration were illustrat-ed.