Left Ventricular Volume Measurements in Man by Thermodilution*

Abstract

A safe, rapid method for estimating left ventricular volume in man during the course of hemodynamic studies should prove helpful in the assessment of cardiac disease and useful in physiological research. It is the purpose of this report to present left ventricular volume measurements in man that were obtained by an indicator dilution method which employs cold as the indicator. This circulatory indicator has been studied by several workers (1-4) and has been used for left ventricular volume determinations in animals previously (5-10). The method employed was adapted from those used by Rapaport and his co-workers for left ventricular volume measurements in the dog (7) and right ventricular studies in man (11). MethodsThirty-eight patients were studied during diagnostic left heart catheterization. The left ventricle was catheterized by the percutaneous transseptal method, utilizing a Teflon catheter which has four side holes near its tip (12). Left atrial pressure was measured before and after ventricular catheterization. A brachial artery was cannulated percutaneously with a 15-cm length of polyethylene tubing. A 6F Teflon catheter was introduced percutaneously into the right femoral artery and advanced until its tip was slightly above the aortic valve, as judged fluoroscopically. Left heart pressures were measured with a P-23G strain gage' and systemic arterial pressure with a P-23D gage.' These pressures and the electrocardiogram were recorded with a direct-writing four channel oscillograph. system and that it present an exponential series of decreasing, steplike concentrations. In these studies cold was used as the indicator and was delivered rapidly into the left ventricle by injections of 5 ml of cooled saline. Rarely, 10-to 15-ml injections were given in patients with extremely large ventricular volumes. A bead thermistor in the proximal aorta served as the sampling system. The thermistor catheter was of nylon (o. d., 0.97 mm) with a closed end and had a rapidly responding thermistor bead mounted at its tip.3 This catheter was 1 cm longer than the radiopaque aortic catheter and was inserted into the latter when thermodilution curves were to be recorded. This placed the thermistor into the blood stream just above the aortic valve. Immediately after recording the thermodilution curves and cardiac output by dye dilution, the aortic catheters were removed to avoid the possibility of thrombosis.The thermistor was employed as one arm of a Wheatstone bridge that was activated by a mercury battery. Approximately 0.1 v was presented to the thermistor itself. The resulting signal was amplified by a type 53/54 D preamplifier4 and displayed with a type RM 565 oscilloscope.4 The electrocardiogram was displayed simultaneously by a type 3 A 74 amplifying electronic switch.4 Records were made by photographing the oscilloscope screen with 35-mm film.The thermistors were calibrated against known temperature in a water bath. The peak change in aortic blood temperature produced by the cold inj ections was usually between 0.3°an...

Left ventricular volume in aortic stenosis measured by an angiocardiographic and a thermodilution method.

“…However, 6 of our patients studied by thermodilution had enddiastolic volumes within the normal range. These results are in close agreement with the findings of other workers who also report abnormally large enddiastolic volumes in some patients when measured by indicator dilution Bristow et al, 1964;Folse and Braunwald, 1962) and by angiocardiography (Jones et al, 1964). Linden and Mitchell (1960) have shown that in dogs the end-diastolic length of a ventricular muscle segment is related to end-diastolic pressure, and Braunwald et al (1960) have demonstrated that this also applies in man.…”

Left heart haemodynamics at rest and during exercise in patients with mitral stenosis.

“…It is still debatable, however, whether an increase in left ventricular end-diastolic pressure is an accurate sign of left heart failure (Braunwald and Ross, 1963), since no correlation has been found between the end-diastolic pressure and the blood volume in the left ventricle in patients with mitral stenosis. The diastolic left ventricular volume in patients with mitral stenosis did not differ from that in the controls (Folse and Braunwald, 1962;Bristow et al, 1964;Gorlin et al, 1964). Dye dilution techniques, commonly used for estimating end-diastolic blood volume, give excessively high results (Bartle and Sanmarco, 1966;Carleton, Bowyer, and Graettinger, 1966).…”

The effects of posture and isoproterenol on the velocity of left ventricular contraction in man

“…It is also possible in such studies to construct indices of ventricular wall force and of velocity of ventricular wall shortening during systole utilizing measurements of left ventricular volume and pressure (18)(19)(20)(21). The present investigation was undertaken to determine whether or not it is feasible, utilizing thermodilution to measure left ventricular end-diastolic (LVEDV) and end-systolic (LVESV) volumes (22)(23)(24)(25), to apply the concepts of force-velocity and length-velocity relations of isolated cardiac muscle to the assessment of left ventricular adaptation in conscious normal human subjects. In this study, mean left ventricular wall force (MFE) and mean rate of circumferential shortening (MRCS) during ejection were calculated, assuming that the ventricle behaves as a contracting, thin-walled sphere.…”