Studies on Pulsed-wave Doppler Echocardiographic Parameters of Blood Flow through Mitral, Tricuspid and Aortic Valves in Healthy Indian Spitz Dogs
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B-4256
[1-6]
RESEARCH ARTICLE Indian Journal of Animal Research, Volume Issue : ()
Studies on Pulsed-wave Doppler Echocardiographic Parameters
of Blood Flow through Mitral, Tricuspid and Aortic Valves in
Healthy Indian Spitz Dogs
Deepti Bodh, Mozammel Hoque, Abhishek Chandra Saxena 10.18805/IJAR.B-4256
ABSTRACT
Background: Pulsed-wave Doppler measures blood flow at specific point and provides information on velocity, direction and uniformity
of blood flow throughout cardiac cycle. Till date, there is no published data on study of cardiac parameters using pulsed-wave Doppler
echocardiography in Indian Spitz dogs.
Methods: Twenty-four clinically normal Indian Spitz dogs were subjected to pulsed-wave Doppler echocardiography to determine the
reference intervals for Doppler parameters of blood flow through mitral, tricuspid and aortic valves. Mitral peak E and A-wave velocities,
E/A ratio, deceleration time, isovolumic relaxation time, E and A-wave velocity time integral, E duration and A duration were 0.69±0.09
m/s, 0.43±0.12 m/s, 1.69±0.45, 111.25±35.94 ms, 48.50±24.77 ms, 0.07±0.01 m and 0.04±0.02 m, 196.88±44.38 ms and 181.25±64.89
ms, respectively. Tricuspid peak E and A-wave velocities, E/A ratio and E and A-wave velocity time integral were 0.57±0.11 m/s,
0.38±0.08 m/s, 1.56±0.32 and 0.07±0.02 m and 0.05±0.01 m, respectively. Aortic peak velocity, velocity time integral and ejection
time were 0.87±0.07 m/s, 0.11±0.02 m and 0.25±0.04 s, respectively.
Conclusion: The reference values of flow parameters across mitral, tricuspid and aortic valves using pulsed-wave Doppler
echocardiography were determined. Mitral, tricuspid and aortic valve flow variables were unaffected by gender whereas isovolumic
relaxation correlated positively with body weight.
Key words: Cardiac valves, Echocardiography, Indian spitz, Pulsed-wave doppler
INTRODUCTION
Division of Surgery, ICAR-Indian Veterinary Research Institute,
Doppler echocardiography is a non-invasive means of
Izatnagar, Bareilly-243 122, Uttar Pradesh, India.
demonstrating velocity of blood flow across cardiac valves.
Intracardiac blood flow velocities and variables obtained from Corresponding Author: Deepti Bodh, Department of Surgery and
Radiology, College of Veterinary and Animal Sciences, GBPUAT,
Doppler waveform provide information on systolic as well
Pantnagar-263145, Uttarakhand, India. Email: deeptibodh@yahoo.in
as diastolic ventricular function.
There is wide variation in Doppler echocardiographic How to cite this article: Bodh, D., Hoque, M. and Saxena, A.C.
values derived from mixed population of dogs (Brown et al., (2021). Studies on Pulsed-wave Doppler Echocardiographic
1991; Schober et al., 1998; Pereira et al., 2009; Jeyaraja et al., Parameters of Blood Flow through Mitral, Tricuspid and Aortic
Valves in Healthy Indian Spitz Dogs. Indian Journal of Animal
2016) due to differences in their breed, gender and body
Research. DOI: 10.18805/IJAR.B-4256.
weight. Above reference values when used for a particular
Submitted: 21-07-2020 Accepted: 02-01-2021 Online: 01-03-2021
breed of dog may result in erroneous interpretation of cardiac
data. Thus, there is a need to establish reference limits
Due to lack of reference values of Doppler echocardiography
defining normalcy so as to differentiate between the normal
in Indian Spitz dogs the present study was designed to
and abnormal Doppler findings as well as accurately interpret
determine the reference intervals for pulsed-wave Doppler
Doppler indices of cardiac function.
derived parameters of blood flow through mitral, tricuspid
Pulsed-wave Doppler measures blood flow at a specific
and aortic valves and, to further study the effect of gender
point and provides information on velocity, direction and
and body weight on Doppler echocardiographic variables
uniformity of blood flow throughout the cardiac cycle (Boon,
in Indian Spitz dogs.
2011). Breed specific pulsed-wave Doppler
echocardiographic reference values are available for MATERIALS AND METHODS
German shepherd and Beagle (Kirberger et al., 1992a),
The present study is a part of first authors PhD thesis
Boxer (Schober et al., 2002; Cavalcanti et al., 2007),
submitted in year 2015 to Division of Surgery, ICAR-Indian
Retriever (Kobal and Petric, 2007), Doberman pinscher
Veterinary Research Institute (IVRI), Izatnagar, Bareilly.
(O’Sullivan et al., 2007) and Indian mongrel dogs (Bodh et al.,
2020). The study on cardiac parameters in Indian Spitz dogs Animals
using pulsed-wave Doppler echocardiography has not been Client owned healthy Indian Spitz (12 males and 12 females),
reported so far. aged 3-5 yr (mean age = 4.25±0.54 yr) and weighing 10-13
VOLUME ISSUE () 1Studies on Pulsed-wave Doppler Echocardiographic Parameters of Blood Flow through Mitral, Tricuspid and Aortic...
kg (mean body weight = 11.88±0.68 kg) presented to calculated to determine influence of body weight on Doppler
Referral Veterinary Polyclinics, Indian Veterinary Research echocardiographic variables. Correlation was positive and
Institute for routine clinical check up were studied. All dogs significant when correlation coefficient was 0.40 and
had normal cardiovascular and physical examination significance was 0.05.
findings, no obvious signs of cardiac disease and showing
normal findings of routine six-lead ECG, M-mode, two RESULTS AND DISCUSSION
dimensional and Doppler echocardiography. Owners Data are presented as mean values ± standard deviation
consent was obtained before each examination. (SD). Pulsed-wave Doppler echocardiographic parameters
Echocardiographic examination of blood flow through mitral, tricuspid and aortic valves are
summarized in Table 1. Subjective comparison of reference
Echocardiographic examination was performed using a
values of Indian Spitz dogs with values obtained from mixed
Digital Colour Doppler Ultrasound System (Chison iVis 60
dog population and breed specific reference values are
Expert Vet®), Chison Medical Imaging Co., Ltd. equipped
presented in Table 2 and 3, respectively. Doppler
with a 3.5-5.5 MHz multi frequency phased array transducer.
echocardiographic parameters differed non-significantly
All examinations were performed in non-sedated awake
between male and female dogs. Except isovolumic relaxation
dogs. Standard procedures for Doppler examination, imaging
time, none of the Doppler echocardiographic parameters
plane and sample volume positions were used (Kirberger
correlated significantly with body weight (Table 4).
et al., 1992a).
The pattern of blood flow through mitral valve during
Trans-mitral flow pattern with E and A wave velocities
diastole was positive and laminar with E and A waves, both
were obtained from left caudal (apical) four chamber view
having a spiked triangular appearance. Peak E velocity seen
of heart, with sample volume positioned in the left ventricle
during rapid filling phase of early diastole was similar to
just distal to mitral annulus at the point of maximal opening
values reported by Darke et al. (1993) and Jayaraja et al.
of mitral valves. Doppler curves were traced to determine
(2016) but lower than values reported by Kirberger et al.
peak early and late diastolic filling velocities (E peak and A
(1992a) and Schober et al. (1998).Peak A velocity seen in
peak, respectively), ratio of peak early to peak late diastolic
late diastole due to atrial contraction was similar to value
flow (E/A ratio), velocity time integral of early and late
reported by Darke et al.(1993), but lower than values
diastolic inflow (VTIE and VTIA, respectively), deceleration
reported by Kirberger et al.(1992a), Schober et al.(1998)
time of early diastolic flow (DTE) and duration of early and
and Jayaraja et al. (2016). Mitral E/A ratio was within the
late diastolic inflow waves (E duration and A duration,
reference range published for healthy dogs (Kirberger et
respectively). Isovolumic relaxation time (IVRT) was
al.,1992a), but slightly greater than values reported by Darke
determined from left caudal (apical) parasternal long axis
et al. (1993), Yamamoto et al. (1993), Schober et al. (1998)
five chamber view with sample volume positioned between
and Jayayraja et al. (2016). In normal animals, the E:A ratio
the septal mitral leaflet and left ventricular outflow tract.
is always greater than 1, because the rapid ventricular filling
Imaging planes providing best flow profile with highest
peak (E-wave) is higher than atrial contraction peak (A-
velocities, least spectral broadening and good definition to
wave).In impaired ventricular relaxation, ventricles fail to
E and A peaks were selected.
relax completely until late in diastole and atrial contraction
Tricuspid flow pattern with E and A wave velocities were
contributes more to ventricular filling resulting in higher peak
obtained from left caudal (apical) four chamber view of heart
A velocities and E:A ratio less than 1.In addition, lower peak
with sample volume positioned in right ventricle, just distal
E velocity might also be due to smaller pressure gradients
to tricuspid annulus at the point of maximal opening of
between left atrium and ventricle. In restrictive pattern, high
tricuspid valve. Peak E and A wave velocities and E/A ratio
filling pressures are predominant as most of ventricular filling
was measured from pulsed-wave Doppler tracings of
occurs early in diastole and less occurs during atrial systole
tricuspid inflow.
resulting in very high pressure within left ventricle leading
Aortic flow pattern was obtained from left caudal (apical)
to a high E:A ratio.
long axis view of left ventricular outflow region and
Velocity time integral (VTI) represented area covered
occasionally from an apical five chamber view. Sample
under two velocity peaks measured by manually tracing the
volume was positioned distal to the aortic valve. Aortic peak
modal velocity envelop of Doppler signal. Velocity time
velocity, velocity time integral and ejection time (ET) i.e. time
interval between start to end of aortic blood flow signal were integral of mitral E-wave (VTIE) was similar to value reported
recorded. by Schober et al. (1998), but smaller than value reported by
Yamamoto et al. (1993) in normal dogs. Velocity time integral
Statistical analysis of mitral A-wave (VTIA) was greater than value reported by
Statistical analysis was performed using SPSS version 17 Schober et al. (1998).An increase in VTI represents
(SPSS Inc., Chicago, IL). Mean value of male and female increased volume or restriction to flow whereas decreased
dogs were compared using unpaired Student’s t-test. A value VTI indicates poor blood flow (Boon, 2011). Peak E and A-
of PStudies on Pulsed-wave Doppler Echocardiographic Parameters of Blood Flow through Mitral, Tricuspid and Aortic...
Table 1: Pulsed-wave Doppler echocardiographic parameters of mitral, tricuspid and aortic valve flows in Indian Spitz dogs.
Parameters Male dogs Female dogs Total
Mitral valve
E (m/s)* 0.67±0.09 (0.60-0.75) 0.71±0.09 (0.63-0.79) 0.69±0.09 (0.64-0.74)
A (m/s) 0.47±0.10 (0.38-0.56) 0.39±0.13 (0.28-0.50) 0.43±0.12 (0.36-0.49)
E/A ratio 1.57±0.40 (1.23-1.91) 1.82±0.49(1.42-2.23) 1.69±0.45 (1.46-1.94)
VTIE (m) 0.07±0.01 (0.06-0.08) 0.08±0.01 (0.08-0.08) 0.07±0.01 (0.07-0.08)
VTIA (m) 0.05±0.02 (0.03-0.06) 0.04±0.01 (0.03-0.04) 0.04±0.02 (0.03-0.05)
E dur (ms) 181.25±38.71 (148.89-213.61) 212.50±46.52 (173.61-251.39) 196.88±44.38 (173.23-220.52)
A dur (ms) 186.25±81.93 (117.75-254.75) 176.25±47.49 (136.55-215.95) 181.25±64.89 (146.67-215.83)
DT E (ms) 101.50±18.32 (77.18-107.82) 123.00±40.36 (96.26-163.74) 111.25±35.94 (92.10-130.40)
IVRT (ms) 71.25±20.91 (45.41-97.09) 58.75±16.42 (45.02-72.48) 48.50±24.77 (51.80-78.20)
Tricuspid valve
E (m/s)* 0.57±0.11 (0.48-0.66) 0.58±0.12 (0.47-0.68) 0.57±0.11 (0.51-0.63)
A (m/s) 0.35±0.05(0.30-0.39) 0.40±0.09 (0.33-0.48) 0.38±0.08 (0.33-0.42)
E/A ratio 1.65±0.29 (1.40-1.90) 1.47±0.34 (1.19-1.75) 1.56±0.32 (1.39-1.73)
VTIE (m) 0.07±0.02 (0.05-0.09) 0.07±0.01 (0.06-0.08) 0.07±0.02 (0.06-0.08)
VTIA (m) 0.04±0.01 (0.03-0.05) 0.05±0.01 (0.04-0.06) 0.05±0.01 (0.04-0.05)
Aortic valve
Ao peak(m/s) 0.87±0.08 ( 0.80-0.93) 0.91±0.06 (0.86-0.96) 0.87±0.07 (0.85-0.93)
Ao VTI (m) 0.11±0.01 (0.09-0.12) 0.11±0.02 (0.09-0.13) 0.11±0.02 (0.09-0.12)
Values within parenthesis indicate lower and upper 95% confidence intervals. *P 0.05, significantly different at 5%.
E, peak flow velocity at early diastole; A, peak flow velocity at late diastole; E/A, ratio of early to late diastolic peak flow velocities; VTIE,
velocity time integral of early diastolic flow; VTIA, velocity time integral of late diastolic flow; DTE, deceleration time of early diastolic flow;
IVRT, isovolumic relaxation time; E dur, duration of early diastolic transmitral flow; A dur, duration of late diastolic transmitral flow; Ao
peak, peak aortic flow velocity; Ao VTI, aortic velocity time integral.
Table 2: Subjective comparison of pulsed-wave Doppler echocardiographic parameters of Indian Spitz dogs with reference values
obtained from mixed dog population.
Present study Schober et al. Kirberger et al. Darke et al. Yamamoto et al. Pereira et al. Jayaraja et al.
Parameters
(Indian Spitz) (1998) (1992a) (1993) (1993) (2009) (2016)
Mitral v.
E (m/s)* 0.69±0.09 0.73±0.11 0.91±0.15 0.65-0.08 0.56±0.18 0.75±0.11 0.69±0.02
A (m/s) 0.43±0.12 0.48±0.16 0.63±0.13 0.43±0.13 0.44±0.11 0.49±0.06 0.50±0.03
E/A ratio 1.69±0.45 1.63 ±0.47 1.48±0.31 1.55±0.36 1.30±0.30 1.53±0.19 1.43±0.05
VTIE (m) 0.07±0.01 0.06±0.01 NR NR 0.09±0.03 NR NR
VTIA (m) 0.04±0.02 0.02±0.01 NR NR NR NR NR
E dur (ms) 196.88±44.38 125±21 NR NR NR NR NR
A dur (ms) 181.25±64.89 75±10 NR NR NR NR NR
DT E (ms) 111.25±35.94 81±17 NR NR NR 89±9.2 NR
IVRT (ms) 48.50±24.77 60±20 NR NR NR 80±9.0 NR
Tricuspid v.
E (m/s)* 0.57±0.11 NR 0.86±0.02 NR 0.71±13.38 NR 0.58±0.03
A (m/s) 0.38±0.08 NR 0.58±0.16 NR 0.45±2.35 NR 0.40±0.03
E/A ratio 1.56±0.32 NR 1.60±0.56 NR 1.62±0.29 NR 1.40±0.04
VTIE (m) 0.07±0.02 NR NR NR NR NR NR
VTIA (m) 0.05±0.01 NR NR NR NR NR NR
Aortic v.
Peak vel.(m/s) 0.87±0.07 NR 1.57±0.33 1.19±0.24 NR NR 1.19±0.04
Ao VTI (m) 0.11±0.02 NR NR NR NR NR NR
NR, not reported. E, peak flow velocity at early diastole; A, peak flow velocity at late diastole; E/A, ratio of early to late diastolic peak flow
velocities; VTIE, velocity time integral of early diastolic flow; VTIA, velocity time integral of late diastolic flow; DT E, deceleration time of
early diastolic flow; IVRT, isovolumic relaxation time; E dur, duration of early diastolic transmitral flow; A dur, duration of late diastolic
transmitral flow; Ao VTI, aortic velocity time integral.
VOLUME ISSUE () 34
Table 3: Subjective comparison of pulsed-wave Doppler echocardiographic parameters of Indian Spitz dogs with breed specific reference values from literature.
Present study Schober et al., Muzzi et al., Cavalcanti et al., Kobal and Petric, Kobal and Petric, O’Sullivan et al., Bodh et al.,
Parameters (Indian Spitz) 2002 (Boxer) 2006 (German 2007(Boxer) 2007(Doberman 2007(Retrievers) 2007 (Doberman 2020 (Indian
Shepherd) Pinscher) Pinscher) mongrel dogs)
Mitral valve
E (m/s)* 0.69±0.09 0.76±0.13 0.74±0.08 0.81±0.18 0.82±0.11 0.77±0.15 0.76±0.13 0.73±0.14
A (m/s) 0.43±0.12 0.52±0.12 0.44±0.07 0.51±0.11 0.66±0.11 0.58±0.12 0.55±0.10 0.47±0.11
E/A ratio 1.69±0.45 1.47±0.34 NR 1.58±0.19 1.26±0.19 1.34±0.24 1.4±0.3 1.58±0.37
VTIE (m) 0.07±0.01 NR NR NR NR NR NR 0.11±0.03
VTIA (m) 0.04±0.02 NR NR NR NR NR NR 0.06±0.02
E dur (ms) 196.88±44.38 NR NR NR NR NR NR 276.87±77.69
A dur (ms) 181.25±64.89 NR NR NR NR NR NR 245.0±105.89
DT E (ms) 111.25±35.94 77±14 132.6±16.44 83.04±13.07 142±27 94.1±29.8 131±24 145.63±68.89
IVRT (ms) 48.50±24.77 53±8 NR 93.46±19.98 58±14 60.7±16.76 83±14 55.94±15.83
Tricuspid val.
E (m/s)* 0.57±0.11 NR 0.67±0.12 0.71±0.13 NR NR NR 0.58±0.11
A (m/s) 0.38±0.08 NR NR 0.45±0.12 NR NR NR 0.31±0.09
E/A ratio 1.56±0.32 NR NR 1.62±0.29 NR NR NR 2.01±0.49
VTIE (m) 0.07±0.02 NR NR NR NR NR NR 0.11±0.03
VTIA (m) 0.05±0.01 NR NR NR NR NR NR 0.05±0.03
Aortic valve
Peak vel.(m/s) 0.87±0.07 NR 1.02±0.143 NR NR NR NR 1.03±0.12
Ao VTI (m) 0.11±0.02 NR NR NR NR NR NR 0.12±0.03
NR, not reported.
E, peak flow velocity at early diastole; A, peak flow velocity at late diastole; E/A, ratio of early to late diastolic peak flow velocities; VTIE, velocity time integral of early diastolic flow;
VTIA, velocity time integral of late diastolic flow; DTE, deceleration time of early diastolic flow; IVRT, isovolumic relaxation time; E dur, duration of early diastolic transmitral flow; A dur,
duration of late diastolic transmitral flow; Ao VTI, aortic velocity time integral.
Studies on Pulsed-wave Doppler Echocardiographic Parameters of Blood Flow through Mitral, Tricuspid and Aortic...
Indian Journal of Animal ResearchStudies on Pulsed-wave Doppler Echocardiographic Parameters of Blood Flow through Mitral, Tricuspid and Aortic...
of Pereira et al. (2009) and
In this Bodh etyou
regards al. (2020), but contrary
may please reply greater
of than values
the reviewer reported mail.
comments previously (Schober et al.,
to findings of O’Sullivan et al. (2007) in Doberman Pinschers 1998; O’Sullivan et al., 2007 and Bodh et al., 2020).
where majority of Doppler echocardiographic variables Peak tricuspid E-wave velocity was similar to values
correlated significantly with body weight. reported by Darke et al. (1993) and Jayaraja et al. (2016)
Time interval from peak to end of mitral E-wave but smaller than values reported by Kirberger et al. (1992a)
represented mitral deceleration time (DT E).Value in Indian and Yamamoto et al. (1993).Tricuspid peak A-wave velocity
Spitz were lower than German Shepherd (Muzzi et al., 2006), was similar to value reported by Darke et al. (1993) but lower
Doberman Pinscher (O’ Sullivan et al., 2007) and Indian than values reported by Kirberger et al. (1992a), Yamamoto
mongrel dogs (Bodh et al., 2020).Mitral DTE correlated non- et al. (1993) and Jayaraja et al. (2016). Tricuspid E/A ratio
significantly with gender and body weight similar to findings was within the reference range published for healthy dogs
in Indian mongrel dogs (Bodh et al., 2020). To its, contrary, by Kirberger et al. (1992a) but lower than value reported by
Schober and Fuentes (2001) and O’ Sullivan et al. (2007) Darke et al. (1993). An increase in the right atrial pressure
reported a significant effect of body weight on mitral DTE . or volume secondary to tricuspid insufficiency resulted in
Insignificant effect of body weight on DTE in present study increased tricuspid peak E velocity. The E and A peaks of
might be due to narrow range of body weights used. In tricuspid flow and their VTI’s showed no correlation with
impaired relaxation as in hypertrophic cardiomyopathy, left gender and body weight, similar to finding in normal dogs
ventricle takes longer time to relax and allow filling leading (Kirberger et al., 1992a)
to prolonged deceleration time. W hile in restriction to Peak E velocity of mitral flow was significantly (PStudies on Pulsed-wave Doppler Echocardiographic Parameters of Blood Flow through Mitral, Tricuspid and Aortic...
Similar to findings of Kirberger et al. (1992a), aortic peak Journal of Advanced Veterinary Science and Technology.
velocity did not correlated significantly with gender and body 5: 256-265.
weight. Reduction in peak aortic flow velocity correlates to Kirberger, R.M., Van Den Berg, P.B., Daradz, B. (1992a). Doppler
decreased left ventricular systolic function as seen in severe echocardiography in the normal dog: Part I. Velocity
dilated cardiomyopathy. This could be due to good findings and flow patterns. Veterinary Radiology and
correlation between aortic peak flow velocity and left Ultrasound. 33: 370-379.
Kirberger, R.M., Van Den Berg, P.B., Grimbeek, R.J. (1992b).
ventricular fractional shortening.
Doppler echocardiograpy in the normal dog: Part II.
Factors influencing blood flow velocities and a comparison
CONCLUSION between left and right heart flows. Veterinary Radiology
Reference values of blood flow velocities through mitral, and Ultrasound. 33: 380-386.
tricuspid and aortic valves in healthy Indian Spitz dogs was Kobal, P. and Petric, A.D. (2007). Echocardiographic diastolic
determined using pulsed-wave Doppler echocardiography. indices of left ventricle in normal Doberman Pinschers
Establishing normal values of important pulsed-wave and Retrievers. Slovenian Veterinary Research. 44: 31-40.
Doppler derived blood flow velocities will help clinicians to Muzzi, R.A.L., Muzzi, L.A.L., de Araujo, R.B. and Cherem, M. (2006).
interpret these indices of cardiac function in clinical cases Echocardiographic indices in normal German shepherd
and diagnose a variety of pathological cardiac conditions. dogs. Journal of Veterinary Science. 7: 193-198.
O’Sullivan, M.L., O’Grady, M.R. and Minors, S.L. (2007). Assessment
of diastolic function by Doppler echocardiography in
ACKNOWLEDGEMENT normal Doberman Pinschers and Doberman Pinschers
The authors would like to thank the Director, ICAR-Indian with dilated cardiomyopathy. Journal of Veterinary Internal
Veterinary Research Institute for providing necessary facility Medicine. 21: 81-91.
for the conduct of research work. Pereira, G.G., Santos, L.C., Yamaki, A.L.F. and Larsson, M.H.M.A.
(2009). Evaluation of left ventricular diastolic echocardiographic
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