Summary
This is an aecount of 2 groups of 10 patients each who received Starr Edwards ball valves in either the mitral (M) or aortic (A) position on average 14.7 ± 3 or 14.9 ± 2.4 years ago, respectively. Non-invasive scintigraphic studies were performed using the first pass of 18 to 20 mCi 99 m-Technetium Pertechnetate. Enddiastolic and endsystolic volumes were found elevated at rest: (M) EDV 135 ± 50 ml, ESV 63 ± 30 ml; (A) EDV 163 ± 41 ml, ESV 69 ± 25 ml. The response to maximum exercise - during which the heart rate increased from 85 ± 23 min-1 to 133 ± 33 min-1 - was abnormal, since none of the volumes changed significantly. During exercise, therefore, the increase of the cardiac Output was totally heart rate dependent: (M) 6.1 ± 2.3 to 9.3 ± 2.3 l/min; (A) 7.0 ± 1.9 to 10.9 ± 3.1 l/min.
The dynamics of the rapid diastolic filling rate of the left ventricle (RFR) and the mean pulmonary transit time (MTT) served as functional Parameters of the Starr Edwards ball valves in the mitral position. The rapid filling rate increased from 205 ± 98 to 321 ± 58 ml/sec, whereas MTT decreased from 7.4 ± 1.4 to 5.4 ± 2.1 sec. In patients with aortic valve replacement the left ventricular ejection rate was assessed, it rose from 233 ± 80 to 459 ± 232 ml/sec. The significant changes of the Parameters proved that the Starr Edwards ball valve mechanism funetions satisfactorily 11 to 19 years post-operatively.
Key words
Artificial valves - Long-term follow-up
