Dicrotic Pulse Research Articles

Gold Nanoparticle Thin Film-Based Strain Sensors for Monitoring Human Pulse

A concise and economical way to build nanoparticle thin-film strain sensors of high gauge factors on a flexible polydimethylsiloxane substrate is developed. The gauge factors for resistance change and capacitance change are much larger than those of many other competing sensors. The small bulk modulus of the substrate provides the sensor a large responsivity for pressure with a frequency bandwidth of kHz. It can be used for tactile sensing that is capable of monitoring human pulse for pre-clinical diagnosis, by resolving minor structures such as peaks of dicrotic pulse and before dicrotic pulse in the waveforms.

Quantification of radial arterial pulse characteristics change during exercise and recovery

It is physiologically important to understand the arterial pulse waveform characteristics change during exercise and recovery. However, there is a lack of a comprehensive investigation. This study aimed to provide scientific evidence on the arterial pulse characteristics change during exercise and recovery. Sixty-five healthy subjects were studied. The exercise loads were gradually increased from 0 to 125 W for female subjects and to 150 W for male subjects. Radial pulses were digitally recorded during exercise and 4-min recovery. Four parameters were extracted from the raw arterial pulse waveform, including the pulse amplitude, width, pulse peak and dicrotic notch time. Five parameters were extracted from the normalized radial pulse waveform, including the pulse peak and dicrotic notch position, pulse Area, Area1 and Area2 separated by notch point. With increasing loads during exercise, the raw pulse amplitude increased significantly with decreased pulse period, reduced peak and notch time. From the normalized pulses, the pulse Area, pulse Area1 and Area2 decreased, respectively, from 38 ± 4, 61 ± 5 and 23 ± 5 at rest to 34 ± 4, 52 ± 6 and 13 ± 5 at 150-W exercise load. During recovery, an opposite trend was observed. This study quantitatively demonstrated significant changes of radial pulse characteristics during different exercise loads and recovery phases.

Wavelet representation of the corneal pulse for detecting ocular dicrotism.

PurposeTo develop a reliable and powerful method for detecting the ocular dicrotism from non-invasively acquired signals of corneal pulse without the knowledge of the underlying cardiopulmonary information present in signals of ocular blood pulse and the electrical heart activity.MethodsRetrospective data from a study on glaucomatous and age-related changes in corneal pulsation [PLOS ONE 9(7),(2014):e102814] involving 261 subjects was used. Continuous wavelet representation of the signal derivative of the corneal pulse was considered with a complex Gaussian derivative function chosen as mother wavelet. Gray-level Co-occurrence Matrix has been applied to the image (heat-maps) of CWT to yield a set of parameters that can be used to devise the ocular dicrotic pulse detection schemes based on the Conditional Inference Tree and the Random Forest models. The detection scheme was first tested on synthetic signals resembling those of a dicrotic and a non-dicrotic ocular pulse before being used on all 261 real recordings.ResultsA detection scheme based on a single feature of the Continuous Wavelet Transform of the corneal pulse signal resulted in a low detection rate. Conglomeration of a set of features based on measures of texture (homogeneity, correlation, energy, and contrast) resulted in a high detection rate reaching 93%.ConclusionIt is possible to reliably detect a dicrotic ocular pulse from the signals of corneal pulsation without the need of acquiring additional signals related to heart activity, which was the previous state-of-the-art. The proposed scheme can be applied to other non-stationary biomedical signals related to ocular dynamics.

Glaucomatous and age-related changes in corneal pulsation shape. The ocular dicrotism.

PurposeTo ascertain whether the incidence of ocular dicrotic pulse (ODP) increases with age, it is more pronounced in glaucomatous than in normal eyes and whether it is related to cardiovascular activity.Methods261 subjects aged 47 to 78 years were included in the study and classified into four groups: primary open angle glaucoma (POAG), primary angle-closure glaucoma (PACG), glaucoma suspects with glaucomatous optic disc appearance (GODA) and the controls (CG). Additionally, in each group, subjects with ODP were divided into two age subgroups around the median age. A non-contact ultrasonic method was used to measure corneal indentation pulse (CIP) synchronically with the acquisition of electrocardiography (ECG) and blood pulse signals. ODP was assessed from the acquired signals that were numerically processed in a custom written program.ResultsODP incidence was about 78%, 66%, 66% and 84% for CG, GODA, POAG, and PACG group, respectively. With advancing age, the ODP incidence increased for all subjects (Δ = 12%), the highest being for the PACG and POAG groups (Δ = 30%). GODA group did not show an age-related increase in the incidence of ODP.ConclusionsThe ocular dicrotism, measured with non-contact ultrasonic method, was found to be a common phenomenon in elderly subjects. The increased ODP incidence in PACG and POAG group may correspond to either higher stiffness of glaucoma eyes, biochemical abnormalities in eye tissues, changes in ocular hemodynamics, may reflect the effect of medications or be a combination of all those factors. The results of GODA group suggest different mechanisms governing their ocular pulse that makes them less susceptible to generating ODP and having decreased predisposition to glaucoma.

Oscillatory structure of the parameters of the pulse signal of the radial artery

The typology analysis of the spectral density curves of time series obtained from various parameters of unit pulse oscillations was performed. The formal classification (typology) of spectral curves was performed using correlations of peak values of the spectral density of VLF, LF, and HF slow waves. To include a spectral density curve into a particular type, the criteria were introduced that characterize the intensity of these oscillatory components. The experimental data was collected during examinations of children and adolescents that were performed to detect the early stage of arterial hypertension (AH). The distribution of the subjects among the types of spectral density based on various parameters of pulse oscillation was evaluated. The results of the comparative analysis of spectral type distribution for various parameters are shown. This analysis has revealed the most informative spectral parameters for differential diagnosis of conditions of two types: type 1, essential hypertension, and type 2, various functional disorders with a normal blood pressure. It has been found that the parameters of the oscillatory components of dicrotic pulse wave time characteristics are the most informative for detecting hypertension in children.

The Dicrotic Pulse: A Common, Non-Ominous Finding After the Ross Operation

We noted a dicrotic pulse in several patients following a Ross operation. Although the etiology of this unique arterial waveform is not completely understood, it has been reported as a sign of low cardiac output and a poor prognosis. We reviewed preoperative echocardiograms and postoperative radial arterial pressure tracings in 33 patients who underwent a Ross procedure between 2000 and 2004. We found a dicrotic pulse to occur commonly (20/33; 61%) following a Ross operation. Moderate to severe preoperative aortic insufficiency was present in 19/20 patients (95%) in whom a dicrotic pulse was noted and in only 3/13 (23%) who did not exhibit a postoperative dicrotic pulse (p<0.001). A dicrotic pulse was not associated with an increased use of vasoactive infusions or longer hospitalization following the Ross operation. The dicrotic pulse should be recognized as a common postoperative finding in Ross patients that does not herald a delayed postoperative convalescence. The mechanism for a dicrotic pulse in these patients is speculative but may result from changes in vascular compliance secondary to chronic aortic insufficiency.

An Unusual Cause of a “Double Pulse”

We report an unusual cause of a dicrotic pulse that was detected in a patient with no underlying cardiac disease. We postulate that this was the result of elastic recoil from a huge abdominal aortic aneurysm. The palpable double pulsation of either a dicrotic pulse or pulsus bisferiens is evidence of significant cardiac disease but may be associated with other cardiovascular pathology. An Unusual Cause of a “Double Pulse”EJVES ExtraVol. 13Issue 5PreviewWe report an unusual cause of a dicrotic pulse that was detected in a patient with no underlying cardiac disease. We postulate that this was the result of elastic recoil from a huge abdominal aortic aneurysm. The palpable double pulsation of either a dicrotic pulse or pulsus bisferiens is evidence of significant cardiac disease but may be associated with other cardiovascular pathology. Full-Text PDF Open Access

An Unusual Cause of a “Double Pulse”

We report an unusual cause of a dicrotic pulse that was detected in a patient with no underlying cardiac disease. We postulate that this was the result of elastic recoil from a huge abdominal aortic aneurysm. The palpable double pulsation of either a dicrotic pulse or pulsus bisferiens is evidence of significant cardiac disease but may be associated with other cardiovascular pathology.

Dicrotic pulse in pericardial tamponade

ANALYSIS OF THE arterial pressure waveform is useful to the clinician in that alterations in the waveform morphology may indicate changes in cardiovascular parameters, such as stroke volume, systemic vascular resistance, or preload. Distinct arterial waveform morphologies, such as pulsus alternans and pulsus paradoxus, may indicate specific conditions and are helpful in directing therapy. The dicrotic pulse is a unique arterial pressure waveform associated with specific physiologic conditions. Recognition and understanding of factors associated with dicrotic pulse formation should aid the clinician in patient management. As opposed to anacrotic and biferious pulses, in which 2 pulsations occur during systole, a dicrotic pulse is characterized by 2 palpable pulsations with 1 upstroke in systole and 1 upstroke in diastole. Meadows et al1 defined a fully dicrotic pulse when the dicrotic wave (peak of the dicrotic wave pressure dicrotic notch pressure) is 30% of the pulse pressure and when the pressure difference between the dicrotic notch and the diastolic pressure is 10% of pulse pressure. A dicrotic pulse historically has been associated with typhoid fever and more recently described with a variety of low cardiac output states.1,2 After mitral or aortic valve replacement, a dicrotic pulse has been correlated with left ventricular dysfunction and is an indicator of a poor postoperative prognosis.3 This case report describes the occurrence of a dicrotic pulse in a patient with cardiac tamponade that resolved after surgical drainage of pericardial fluid.

Mechanism of the dicrotic pulse.

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 proximal aortic haemodynamic function in both strong and weak beats. It was found that the incisural notch of the aortic pressure signal is not strongly dependent on the extent of left ventricular ejection, and is of essentially normal amplitude even in beats having greatly reduced aortic flow. In contrast, the magnitude of the systolic upstroke of the aortic pressure pulse is strongly determined by the magnitude of left ventricular ejection and is considerably reduced in weak beats. With low cardiac output the relative size of the incisural notch becomes exaggerated in comparison with the overall pulsation, thus creating the characteristic M shaped waveform of the dicrotic pulse.

Mechanism of the dicrotic pulse.

Mechanism of the dicrotic pulse.

Dicrotic pulse after open heart surgery.

Pre- and postoperative echophonocardiograms (EPCGs) and preoperative hemodynamic data of 108 patients who underwent valve replacement were reviewed to establish the frequency and significance of a dicrotic pulse (DP) postoperatively. DP occurred almost exclusively in patients who underwent valve replacement for regurgitant lesions (20 of 28 with aortic regurgitation, nine of 25 with mitral regurgitation, and four of six with both aortic and mitral regurgitation). These patients were divided into dicrotic and nondicrotic groups. Preoperatively, the dicrotic group had significantly larger end-diastolic volumes (p < 0.01) and end-systolic volumes (p < 0.01) and significantly lower ejection fractions (p < 0.01). Echocardiographically, the dicrotic group had larger left ventricular dimensions, both systolic (p < 0.01) and diastolic (p < 0.05), reduced percentage fractional shortening of the left ventricular cavity (p < 0.01) and poor thickening properties of the left ventricular posterior wall (% delta Th-LVPW) (p < 0.01). Postoperatively the dicrotic group had a slightly larger end-diastolic dimension (p = NS) and markedly depressed % delta Th-LVPW (p < 0.001) compared with the nondicrotic group. On follow-up EPCG the persistence of a DP correlated with continued left ventricular dysfunction by echocardiographic and hemodynamic studies and an extremely poor clinical course. DP after valve replacement is therefore an important prognostic sign.

Dicrotic pulse following open heart surgery

Dicrotic pulse following open heart surgery

Dicrotism in heart disease: Correlations with cardiomyopathy, pericardial tamponade, youth, tachycardia, and normotension

Dicrotism of the brachial pulse as seen in this laboratory is highly correlated with congestive cardiomyopathy and pericardial tamponade when these diagnoses are made on patients below the age of 40 who have a heart rate over 90 beats per minute (in regular rhythm). When not present otherwise, the phenomenon may be elicited by occlusive pressure at or just distal to the point from which it is being sensed, and under these circumstances age drops out as a major determinant of its occurrence. Observations from the previous literature as well as from this laboratory also indicate that dicrotism probably occurs with much less frequency in the presence of elevated blood pressures. Barner, Willman, and Kaiser's 20 experience during the early period following prosthetic replacement of the regurgitant aortic valve and our own with cardiomyopathy suggest that certain cardiac disease states may be more likely than others to give rise to dicrotism. There is a need for further clarification of this possibility. Such a study should include significant numbers of all types of heart disease, but it should also be done, insofar as is possible, in the presence of all those other factors known to favor dicrotism. Historically the dicrotic pulse appears to have excited the attention of clinicians of the last third of the nineteenth century as a part of the new knowledge obtained from the sphygmograph introduced by Marey in 1863. As the sphygmograph fell into disuse with the appearance of the sphygmomanometer and the string galvanometer, interest in the dicrotic pulse also waned, and it is only now, late in the resurgence of interest in pulses afforded by the introduction of modern electronic transducers, that dicrotism is again presenting itself for study. It should be recognized that many of the factors giving rise to dicrotism were known to writers of this earlier period.

Dicrotic pulse after open heart operation.

A palpable dicrotic pulse was observed in 18 patients after open heart operation, usually after prosthetic replacement for aortic regurgitation (14 of 18 patients). Two patients had a ventricular septal defect, one had aortic stenosis, and one, mitral insufficiency. The ages of the patients ranged from 9 to 63 years, but the dicrotic pulse was more prominent and persisted longer in younger patients. The dicrotic pulse usually appeared within 48 hours of operation, persisted 1 to 60 days and was always in a brachiocephalic distribution. Determinants of the dicrotic pulse include the stroke volume, the duration of systole, the distensibility of the arterial system, the peripheral reflection coefficient, and the systemic blood pressure. Impaired cardiac function with a low cardiac output was probably the most significant factor in the occurrence of a dicrotic pulse in this series of patients.

The dicrotic arterial pulse.

The study consisted of observations on nine male patients with palpable dicrotic as evidenced by cardiomegaly and the presence of prominent atrial and ventricular diastolic gallop sounds. Most of these patients were diagnosed as having primary myocardial disease. The indirect carotid pulse was characterized by a single systolic wave, a low dicrotic notch, and a large dicrotic wave. The direct brachial arterial pressure pulse had a similar configuration with a shortened ejection time index. The hemodynamic data on these patients was characterized by low cardiac output, low stroke volume, elevated pulmonary arterial wedge pressures, and high total systemic resistance. From these observations we conclude that the presence of a marked dicrotic pulse in afebrile patients at rest may indicate severe functional impairment of the myocardium.

Studies on the Dicrotic Pulse : Third Report. On the Relation between the Dicrotic Pulse and the Age, Pulse Rate and Blood Pressure

Studies on the Dicrotic Pulse : Third Report. On the Relation between the Dicrotic Pulse and the Age, Pulse Rate and Blood Pressure

THE PULSE-FLOW IN THE BRACHIAL ARTERY

It is well known that in most tracings from the peripheral arteries various secondary waves follow the principal or primary wave on the descending limb of the pulse. The chief of these is usually spoken of as the dicrotic wave ; and when this wave can be distinctly felt by the palpating finger on the radial artery, the pulse is described as dicrotic. The typical dicrotic pulse is relatively common in typhoid fever, but it occurs not infrequently in all types of infection. It is also occasionally encountered in other conditions, as, for example in cardiac patients with badly broken compensation. Marked instances of dicrotism are frequently but not invariably associated with low blood-pressure. On the other hand, equally low blood-pressures occur without marked dicrotism. In this as in many other conditions the relation between blood-pressure, whether systolic or diastolic, and pulse form is but a loose one.

On a Case of Abdominal Aneurism with Dicrotic Pulse

On a Case of Abdominal Aneurism with Dicrotic Pulse