A METHOD FOR REPEATED HIGH-FIDELITY MICROMANOMETER MEASUREMENT OF INTRACARDIAC PRESSURES

Dial-tipped, high-fidelity micromanometers were inserted through polyu rethane catheters to acutely measure blood pressures within the chambe rs of the heart and the great vessels of baboons, rhesus monkeys, and goats. Repeated measurements of atrial, ventricular, aortic, and pulmo nary artery pressure were possible with this method, with calibration of micromanometers accomplished immediately prior to and after pressur e recordings to assure data accuracy. All attempts to pass micromanome ters into the atria in all species were successful. Passage of microma nometers from the left ventricle across the aortic value and into the aorta was successful in 97% of the attempts in baboons, 100% for rhesu s monkeys, and 75% for goats; while insertions into the pulmonary arte ry front the right ventricle were successful in 64% of the baboons, 40 % of the rhesus monkeys, and 75% of rite gents. Advantages of this tec hnique are that a permanent conduct for cardiac vascular access is ava ilable and that high-fidelity pressure signals may be acquired.