Abstract Photoplethysmography signal (PPG) provides information about the cardiovascular, respiratory, or nervous system activity. Recent studies proposed methods of apnea identification from PPG using amplitude baseline modulation, area under curve. We hypothesized that analysis dicrotic notch could improve sensitivity and specificity detection. applied four to detect records experimentally ob...

Arterial blood pressure waveforms contain rich pathophysiological information; hence receive much attention in cardiovascular health monitoring. To assist computerized analysis, an automatic delineator was proposed for the fiducial points of arterial blood pressure waveforms, namely their onsets, systolic peaks and dicrotic notches. The presented delineator characterizes arterial blood pressure...

Dicrotic Notch (DN), one of the most significant and indicative features arterial blood pressure (ABP) waveform, becomes less pronounced thus harder to identify as a matter aging pathological vascular stiffness. Generalizable automatic DN identification for such edge cases is even more challenging in presence unexpected ABP waveform deformations that happen due internal external noise sources o...

Low-amplitude pulses to the vasculature increase pulsatile shear stress to the endothelium. This activates endothelial nitric oxide (NO) synthase (eNOS) to promote NO release and endothelial-dependent vasodilatation. Descent of the dicrotic notch on the arterial pulse waveform and a-to-b ratio (a/b; where a is the height of the pulse amplitude and b is the height of the dicrotic notch above the...

Polygraphic recordings were made before and after o6 mg of sublingual nitroglycerin in 20 normal subjects and in 20 patients with ischaemic heart disease. Thefollowing effects of nitroglycerin were observed in both groups: shortening of ejection time, prolongation of pre-ejection period and also of isometric contraction time unrelated to decrease in systolic blood pressure, and increase in hear...

The aim of the present study was to evaluate the mechanism of cerebrovascular autoregulation in patients with neurocardiogenic syncope using bilateral transcranial Doppler (TCD) monitoring during head upright tilt table testing (HUT). Two hundred and six patients were prospectively studied. One hundred and fifty-nine subjects (77%) had a prior history of syncope and 47 (23%) had presyncope. Nin...

The dicrotic pulse is an abnormal carotid pulse found in conjunction with certain conditions characterised by low cardiac output. It is distinguished by two palpable pulsations, the second of which is diastolic and immediately follows the second heart sound. In the course of open chest canine studies of the second heart sound, micromanometers and an electromagnetic flow meter were used to study...