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Introduction Severe aortic stenosis (AS) poses an increased anesthetic risk for noncardiac surgery [1]. Although an echocardiogram provides a definitive diagnosis of AS, clinical findings are important as clues for [...], Purpose A pulsus parvus et tardus of the carotid artery, i.e., a small weak pulse with a delayed systolic peak, is a well-recognized clinical finding of aortic stenosis (AS). However, the diagnostic value of radial arterial pressure curves has not been specifically investigated. In this study, we investigated whether the radial arterial curves of patients with AS had distinguishable characteristics. Methods We studied 17 AS patients (valve area less than 0.8 [cm.sup.2]) and 17 control patients. The durations for the following intervals were measured, from the ECG-R to the beginning of the arterial pressure wave upstroke ([PTT.sub.Up]), from the ECG-R to the peak of the arterial pressure ([PTT.sub.peak]), and the difference between [PTT.sub.peak] and [PTT.sub.Up] ([T.sub.Upstroke]). Results The radial arterial pulse pressures did not differ significantly, indicating absence of a pulsus paruvus in the radial pressure of the AS patients. The [PTT.sub.Up] and [PTT.sub.peak] in the AS patients were 134 ± 18 and 337 ± 44 ms, respectively, while these values in the control patients were 143 ± 21 and 286 ± 64 ms. As a result of the differences in [PTT.sub.Up] and [PTT.sub.peak], the [T.sub.Upstroke] in the AS patients was greater than that in the control patients. The [T.sub.Upstroke] cutoff point that gave the maximal sensitivity (0.93) and specificity (0.65) was 156 ms. Conclusion Our study using the radial arterial curve validated a pulsus tardus as a diagnostic sign for severe AS, while the validity of a pulsus parvus as a diagnostic sign was not confirmed. Keywords Aortic stenosis * Pulse contour * Arterial pressure transit time * Monitoring

Objective: The information derived from central venous catheters is underused. We developed an EKG-R synchronization and averaging system to obtained distinct CVP waveforms and analyzed components of these., Methods: Twenty-five paralyzed surgical patients undergoing CVP monitoring under mechanical ventilation were studied. CVP and EKG signals were analyzed employing our system, the mean CVP and CVP at end-diastole during expiration were compared, and CVP waveform components were measured using this system., Results: CVP waveforms were clearly visualized in all patients. They showed the a peak to be 1.8+/- 0.7 mmHg, which was the highest of three peaks, and the x trough to be lower than the y trough (-1.6+/- 0.7 mmHg and -0.9+/- 0.5 mmHg, respectively), with a mean pulse pressure of 3.4 mmHg. The difference between the mean CVP and CVP at end-diastole during expiration was 0.58+/- 0.81 mmHg., Conclusions: The mean CVP can be used as an index of right ventricular preload in patients under mechanical ventilation with regular sinus rhythm. Our newly developed system is useful for clinical monitoring and for education in circulatory physiology.