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Karlo Romano B Gicana - One of the best experts on this subject based on the ideXlab platform.

  • novel approach to assess cardiac function using Systolic performance and myocardial performance indices from simultaneous electrocardiography and phonocardiography recordings in dogs with various stages of myxomatous mitral valve disease
    Frontiers in Veterinary Science, 2021
    Co-Authors: Karlo Romano B Gicana, Tuchakorn Lertwanakarn, Kittipong Tachampa
    Abstract:

    Background and Objective: Myxomatous mitral valve disease (MMVD) progression entails changes in the structural and functional properties of the heart affecting cardiac timings and Intervals within the cardiac cycle. Conventionally, echocardiography is used to determine the cardiac Time Intervals (CTIs) including Systolic and myocardial performance indices (SPI and MPI) in evaluating cardiac function. Alternatively, these CTIs can also be measured using simultaneous recordings of electrocardiography (ECG) and phonocardiography (PCG) but its use in differentiating MMVD stages remains to be elucidated. This study aimed to establish and prove the use of derived SPI and MPI from a dedicated device as a novel approach to assess cardiac function in different stages of MMVD dogs. Materials and Methods: A prospective study in 52 dogs with different MMVD stages measured the CTIs using a novel device. These were compared and correlated with standard echocardiographic parameters. The predictive value of SPI and three new proposed formulas to estimate MPI (i.e., F1, F2, and F3) in association with asymptomatic from symptomatic MMVD dogs were investigated. Results: Our findings revealed that CTI parameters measured from a novel device including QS1, QS2, S1S2, MPI-F1, and MPI-F2 altered at different stages of MMVD. The SPI and all proposed MPI formulas were comparable to the Systolic Time Interval and Tei index from echocardiography. In addition, the SPI, MPI-F1, and MPI-F2 were significantly correlated with the Tei index. However, the SPI was not able to differentiate the various stages of MMVD. Conversely, only the MPI-F1 (i.e. (QS1+S2)/S1S2) demonstrated good predictive accuracy when compared between asymptomatic and symptomatic MMVD dogs similar to the Tei index. This formula was able to differentiate stages B1 and C with remarkable predictive accuracy, higher sensitivity, and high specificity when compared to the Tei index. Conclusion: We have successfully described the CTI parameters in different MMVD stages using simultaneous ECG and PCG recordings in dogs. Furthermore, we have proven the concept of using the newly proposed parameters from a novel device is equivalent to the Tei index. Thus, we established a novel approach to evaluate cardiac function and its supportive use in the diagnosis of MMVD patients.

  • Novel Approach to Assess Cardiac Function Using Systolic Performance and Myocardial Performance Indices From Simultaneous Electrocardiography and Phonocardiography Recordings in Dogs With Various Stages of Myxomatous Mitral Valve Disease
    'Frontiers Media SA', 2021
    Co-Authors: Karlo Romano B Gicana, Tuchakorn Lertwanakarn, Kittipong Tachampa
    Abstract:

    Background and Objective: Myxomatous mitral valve disease (MMVD) progression entails changes in the structural and functional properties of the heart affecting cardiac timings and Intervals within the cardiac cycle. Conventionally, echocardiography is used to determine the cardiac Time Intervals (CTIs) including Systolic and myocardial performance indices (SPI and MPI) in evaluating cardiac function. Alternatively, these CTIs can also be measured using simultaneous recordings of electrocardiography (ECG) and phonocardiography (PCG), but their values in different MMVD stages remain to be established. This study aimed to establish and prove the use of derived SPI and MPI from a dedicated device as a novel approach to assess cardiac function in different stages of MMVD dogs.Materials and Methods: A prospective study in 52 dogs with different MMVD stages measured the CTIs using a novel device. These were compared and correlated with standard echocardiographic parameters. The predictive value of SPI and three new proposed formulas to estimate MPI (i.e., F1, F2, and F3) in association with asymptomatic from symptomatic MMVD dogs were investigated.Results: Our findings revealed that CTI parameters measured from a novel device including QS1, QS2, S1S2, MPI-F1, and MPI-F2 were altered at different stages of MMVD. The SPI and all proposed MPI formulas were comparable with the Systolic Time Interval and Tei index from echocardiography. In addition, the SPI, MPI-F1, and MPI-F2 were significantly correlated with the Tei index. However, the SPI was not able to differentiate the various stages of MMVD. Conversely, only the MPI-F1 (i.e., (QS1 + S2)/S1S2) demonstrated good predictive accuracy when compared between asymptomatic and symptomatic MMVD dogs similar to the Tei index. Moreover, this formula was able to differentiate stages B1 and C with remarkable predictive accuracy, higher sensitivity, and high specificity when compared with the Tei index.Conclusion: We have successfully described the CTI parameters in different MMVD stages using simultaneous ECG and PCG recordings in dogs. Furthermore, we have proven that the concept of using the newly proposed parameters from a novel device is equivalent to the Tei index. Thus, we established a novel approach to evaluate cardiac function and its supportive use in the diagnosis of MMVD patients

Kittipong Tachampa - One of the best experts on this subject based on the ideXlab platform.

  • novel approach to assess cardiac function using Systolic performance and myocardial performance indices from simultaneous electrocardiography and phonocardiography recordings in dogs with various stages of myxomatous mitral valve disease
    Frontiers in Veterinary Science, 2021
    Co-Authors: Karlo Romano B Gicana, Tuchakorn Lertwanakarn, Kittipong Tachampa
    Abstract:

    Background and Objective: Myxomatous mitral valve disease (MMVD) progression entails changes in the structural and functional properties of the heart affecting cardiac timings and Intervals within the cardiac cycle. Conventionally, echocardiography is used to determine the cardiac Time Intervals (CTIs) including Systolic and myocardial performance indices (SPI and MPI) in evaluating cardiac function. Alternatively, these CTIs can also be measured using simultaneous recordings of electrocardiography (ECG) and phonocardiography (PCG) but its use in differentiating MMVD stages remains to be elucidated. This study aimed to establish and prove the use of derived SPI and MPI from a dedicated device as a novel approach to assess cardiac function in different stages of MMVD dogs. Materials and Methods: A prospective study in 52 dogs with different MMVD stages measured the CTIs using a novel device. These were compared and correlated with standard echocardiographic parameters. The predictive value of SPI and three new proposed formulas to estimate MPI (i.e., F1, F2, and F3) in association with asymptomatic from symptomatic MMVD dogs were investigated. Results: Our findings revealed that CTI parameters measured from a novel device including QS1, QS2, S1S2, MPI-F1, and MPI-F2 altered at different stages of MMVD. The SPI and all proposed MPI formulas were comparable to the Systolic Time Interval and Tei index from echocardiography. In addition, the SPI, MPI-F1, and MPI-F2 were significantly correlated with the Tei index. However, the SPI was not able to differentiate the various stages of MMVD. Conversely, only the MPI-F1 (i.e. (QS1+S2)/S1S2) demonstrated good predictive accuracy when compared between asymptomatic and symptomatic MMVD dogs similar to the Tei index. This formula was able to differentiate stages B1 and C with remarkable predictive accuracy, higher sensitivity, and high specificity when compared to the Tei index. Conclusion: We have successfully described the CTI parameters in different MMVD stages using simultaneous ECG and PCG recordings in dogs. Furthermore, we have proven the concept of using the newly proposed parameters from a novel device is equivalent to the Tei index. Thus, we established a novel approach to evaluate cardiac function and its supportive use in the diagnosis of MMVD patients.

  • Novel Approach to Assess Cardiac Function Using Systolic Performance and Myocardial Performance Indices From Simultaneous Electrocardiography and Phonocardiography Recordings in Dogs With Various Stages of Myxomatous Mitral Valve Disease
    'Frontiers Media SA', 2021
    Co-Authors: Karlo Romano B Gicana, Tuchakorn Lertwanakarn, Kittipong Tachampa
    Abstract:

    Background and Objective: Myxomatous mitral valve disease (MMVD) progression entails changes in the structural and functional properties of the heart affecting cardiac timings and Intervals within the cardiac cycle. Conventionally, echocardiography is used to determine the cardiac Time Intervals (CTIs) including Systolic and myocardial performance indices (SPI and MPI) in evaluating cardiac function. Alternatively, these CTIs can also be measured using simultaneous recordings of electrocardiography (ECG) and phonocardiography (PCG), but their values in different MMVD stages remain to be established. This study aimed to establish and prove the use of derived SPI and MPI from a dedicated device as a novel approach to assess cardiac function in different stages of MMVD dogs.Materials and Methods: A prospective study in 52 dogs with different MMVD stages measured the CTIs using a novel device. These were compared and correlated with standard echocardiographic parameters. The predictive value of SPI and three new proposed formulas to estimate MPI (i.e., F1, F2, and F3) in association with asymptomatic from symptomatic MMVD dogs were investigated.Results: Our findings revealed that CTI parameters measured from a novel device including QS1, QS2, S1S2, MPI-F1, and MPI-F2 were altered at different stages of MMVD. The SPI and all proposed MPI formulas were comparable with the Systolic Time Interval and Tei index from echocardiography. In addition, the SPI, MPI-F1, and MPI-F2 were significantly correlated with the Tei index. However, the SPI was not able to differentiate the various stages of MMVD. Conversely, only the MPI-F1 (i.e., (QS1 + S2)/S1S2) demonstrated good predictive accuracy when compared between asymptomatic and symptomatic MMVD dogs similar to the Tei index. Moreover, this formula was able to differentiate stages B1 and C with remarkable predictive accuracy, higher sensitivity, and high specificity when compared with the Tei index.Conclusion: We have successfully described the CTI parameters in different MMVD stages using simultaneous ECG and PCG recordings in dogs. Furthermore, we have proven that the concept of using the newly proposed parameters from a novel device is equivalent to the Tei index. Thus, we established a novel approach to evaluate cardiac function and its supportive use in the diagnosis of MMVD patients

Jan H Meijer - One of the best experts on this subject based on the ideXlab platform.

  • dynamic response of the initial Systolic Time Interval to a breathing stimulus measured with impedance cardiography
    Journal of Physics: Conference Series, 2010
    Co-Authors: Jan H Meijer, Femke Hoekstra, Esther Habers, Rudolf M Verdaasdonk, Thomas W J Janssen
    Abstract:

    The Initial Systolic Time Interval (ISTI) is a measure for the Time delay between the electrical and mechanical activity of the heart. The present study reports about the dynamic response of ISTI to a Valsalva manoeuvre. This response was investigated in 22 young healthy volunteers, having different levels of training in sports. The Time course of the ISTI during the Valsalva manoeuvre was found to follow a distinct pattern and to be analogous to the course of the Pre-Ejection Period (PEP), also obtained from ECG and ICG signals, reported earlier. The recordings show a definite influence of the Frank-Starling mechanism and are to some extent consistent with reports on the Time course of sympathetic activation. The highly trained subjects showed an ISTI that was systematically longer at all moments of the manoeuvre.

  • relationship between the initial Systolic Time Interval and rr Interval during an exercise stimulus measured with impedance cardiography
    Journal of Physics: Conference Series, 2010
    Co-Authors: Femke Hoekstra, Esther Habers, Thomas W J Janssen, Rudolf M Verdaasdonk, Jan H Meijer
    Abstract:

    The Initial Systolic Time Interval (ISTI), obtained from the electrocardiogram and impedance cardiogram, is considered to be a measure for the Time delay between the electrical and mechanical activity of the heart and reflects an active period of the heart cycle. The relationship between ISTI and the total heart cycle (RR-Interval) was studied in three groups of young, healthy volunteers: low, moderately and highly trained subjects. The three groups were exposed to an exercise stimulus on a cycle ergometer with an increasing work load to increase the heart rate. ISTI was decreased with decreasing RR-Interval. However, the relative proportion of ISTI, ISTI/RR, was found to increase with decreasing RR-Interval. This relationship was found to be inversely proportional. The rate of this increase in ISTI/RR was significantly higher in highly trained subjects. Also, over the whole range of heart rates ISTI was longer in these subjects. It is concluded that ISTI can be used to evaluate cardiac performance during physical exercise non-invasively and in an extramural setting.

  • method to measure autonomic control of cardiac function using Time Interval parameters from impedance cardiography
    Physiological Measurement, 2008
    Co-Authors: Jan H Meijer, Sanne Boesveldt, Eskeline Elbertse, Henk W Berendse
    Abstract:

    The Time difference between the electrocardiogram and impedance cardiogram can be considered as a measure for the Time delay between the electrical and mechanical activities of the heart. This Time Interval, characterized by the pre-ejection period (PEP), is related to the sympathetic autonomous nervous control of cardiac activity. PEP, however, is difficult to measure in practice. Therefore, a novel parameter, the initial Systolic Time Interval (ISTI), is introduced to provide a more practical measure. The use of ISTI instead of PEP was evaluated in three groups: young healthy subjects, patients with Parkinson's disease, and a group of elderly, healthy subjects of comparable age. PEP and ISTI were studied under two conditions: at rest and after an exercise stimulus. Under both conditions, PEP and ISTI behaved largely similarly in the three groups and were significantly correlated. It is concluded that ISTI can be used as a substitute for PEP and, therefore, to evaluate autonomic neuropathy both in clinical and extramural settings. Measurement of ISTI can also be used to non-invasively monitor the electromechanical cardiac Time Interval, and the associated autonomic activity, under physiological circumstances.

Karl Swedberg - One of the best experts on this subject based on the ideXlab platform.

  • neuroendocrine activation in relation to left ventricular function in chronic severe congestive heart failure a subgroup analysis from the cooperative north scandinavian enalapril survival study consensus
    Clinical Cardiology, 1994
    Co-Authors: S V Eriksson, Peter Eneroth, John Kjekshus, J Offstad, Karl Swedberg
    Abstract:

    Left ventricular (LV) function and plasma levels of cardiovascular hormones were examined in patients with severe chronic congestive heart failure (CHF), randomized to placebo or enalapril, in addition to conventional therapy. M-mode echocardiography and plasma hormone concentrations were available at baseline and after 6 weeks of treatment. There was a significant relationship between LV Systolic function and levels of angiotensin-II and norepinephrine. Enalapril increased LV fractional shortening (FS%) (13.3 +/- 5.6 to 15.4 +/- 5.8, p < 0.05) and decreased the Systolic Time Interval index (0.58 +/- 0.14 to 0.48 +/- 0.15, p < 0.05) concurrent with a significant decrease in angiotensin-converting enzyme activity and in aldosterone, angiotensin-II, and norepinephrine concentrations after 6 weeks. No changes were found in the placebo group. However, there was no direct relationship between the amount of change in neurohormones and improvement in LV function after 6 weeks. These findings indicate that in patients with severe chronic CHF, severe LV Systolic dysfunction is associated with high plasma levels of angiotensin-II and norepinephrine, which can be favorably modified by enalapril. This may be of importance for prolonging life in severe heart failure. The lack of relationship between changes in individual hormones and Systolic function suggests complex dynamic interaction. It is, therefore, not sufficient to predict changes in LV function by measuring changes in only one hormone.

Kazuo Momma - One of the best experts on this subject based on the ideXlab platform.

  • effective dose and cardiovascular effects of cilazapril in children with heart failure
    American Journal of Cardiology, 2001
    Co-Authors: Kyosuke Hazama, Makoto Nakazawa, Kazuo Momma
    Abstract:

    A enzyme (ACE) inhibitors are effective for the treatment of heart failure, but their pharmacology and precise hemodynamic effects have not yet been well defined in pediatric patients. The purpose of the present study, therefore, was to clarify acute pharmacologic characteristics and to determine the effective dose of cilazapril, an ACE inhibitor, along with its cardiovascular effects. We chose cilazapril because our preliminary experience in children and data in adults has shown that this ACE inhibitor may have a less renotoxic effect. The present study consisted of 2 steps: the first step was to determine the effective dose of cilazapril and the second step was to show its cardiovascular effects by using the stress-velocity index and aortic blood flow pattern. • • • The first step study included 20 patients, age range from 3 months to 13 years (4.5 3.5 years), who were hospitalized for either diagnostic or interventional cardiac catheterization; none had cyanosis. The 20 patients were divided randomly into 3 groups according to cilazapril dose; group 1 included 7 patients who were given 0.01 mg/kg; group 2 included 8 patients who were given 0.02 mg/kg; and group 3 included 5 patients who received 0.04 mg/kg. Age and body weight were not statistically different in these 3 groups. We determined plasma concentration of cilazaprilat, which is a diacid body and active metabolite of cilazapril, and ACE activity by prevalidated radioenzymatic assays, at 2, 6, 12, and 24 hours after a single oral dose of the medicine. The second step study consisted of 13 patients with congestive heart failure. Heart failure was clinically defined as the use of anticongestive medicine, such as diuretics and/or digoxin, because of persistent cardiomegaly, hepatomegaly, or reduced physical activity. Accordingly, all patients were on diuretics, 4 were on digoxin, and 5 were on isosorbide dinitrate. During the present study, doses of these medications were not changed. Twelve patients took part in the study 1 to 2 months after open heart surgery, and the remaining patient had dilated cardiomyopathy (Table 1). They were in stable heart failure with conventional therapy. Their age averaged 5.0 3.6 years. Cilazapril was administered orally twice a day. The dose was initially 0.01 mg/kg/day to avoid unexpected hypotension, which is often seen after the first dose, and it was gradually increased until apparent cardiovascular effects were confirmed or the dose reached 0.04 mg/kg/day. The 0.04 mg/kg/day dose was determined to be effective by the first step study. After 5 days on the final dose, plasma concentration of cilazaprilat, plasma ACE activity, and plasma renin activity were measured 2 hours after oral ingestion of the drug. By Bor M-mode echocardiography, we measured left ventricular (LV) diastolic and Systolic dimensions, end-Systolic LV posterior wall thickness, and LV preejection and ejection Time according to standard methods. The RR Interval was also measured on an electrocardiogram that was recorded simultaneously with echocardiogrpahic recordings. Fractional shortening (FS) and Systolic Time Interval were also calculated as