Auscultatory Changes Identified through Digital Stethoscope and

Echocardiographic Findings Associated with Healthy Pregnancy

Marilene Miranda Araújo

1,2,3

, Zilma Silveira Nogueira Reis

1,2,3,5

, Renata Baracho Porto

Cláudia Maria Villas Freire

, Vitória Brito Goulart

1,2

, Fabyulla A. Fernandes

, Rosa Celeste Oliveira

and Ricardo Cruz-Correia

Hospital das Clínicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil

Centro de Informática em Saúde, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil

Programa de Pós-graduação em Saúde da Mulher, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil

Escola de Ciência da Informação, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil

CINTESIS Centro de Investigação em Tecnologias e Sistemas de Informação em Saúde, Universidade do Porto,

Porto, Portugal

Keywords: Heart Auscultation, Pregnancy, Medical Informatics, Doppler Echocardiography, Physiological Adaptation.

Abstract: The hyperkinetic hemodynamic pattern and the low viscosity of the blood are typical during pregnancy and

cause a number of auscultatory changes. The main goal of this study was to describe hemodynamic and

auscultatory changes in normal pregnant women and compare them to those of non-pregnant women.

Digital heart auscultation and Doppler echocardiography tests were performed in 29 pregnant and 27 non-

pregnant women, both healthy. Changes in the digital stethoscope auscultation and Doppler

echocardiographic findings were compared between the groups. The low-intensity systolic murmur was

statistically more frequent in the pregnant group (69.0% x 40.7%, p=0.034), as well as B1 Hyperphonesis

(51.7% x 7.4%, p<0.001), B2 Hyperphonesis (69% x 18.5%, p<0.001) and B1 Split (89.7% x 29.6%,

p<0.001). In pregnant women, no associations were found between auscultation findings and Doppler

echocardiogram changes (mitral-murmur x mitral-regurgitation, p=0.675; tricuspid-murmur x tricuspid-

regurgitation, p=1.000; pulmonary-murmur x pulmonary-regurgitation, p=1.000). The digital heart

auscultation of healthy pregnant subjects was able to detect frequent and numerous alterations, confirming

the importance of knowing the physiological changes of pregnancy. The normal Doppler echocardiogram in

all healthy pregnant women with heart murmur indicates that such test has limited applicability for healthy

pregnant subjects, only in cases of suspicion of a heart disease or when it does occur.

1 INTRODUCTION

1.1 The Importance of Tracking and

Diagnosing Heart Diseases during

Pregnancy

Maternal mortality rates are some of the most

critical indicators of quality of life for the population

of any given country, while mainly reflecting on the

quality of health care provided to prenatal pregnant

women. (Cardoso, 2012) Heart disease is universally

considered the main cause of indirect maternal

deaths in the pregnancy-puerperal cycle (Reidy and

Russell, 2011); (Huisman et al., 2013); (Cantwell,

2011). More specifically in Brazil (Saúde., 2006),

failure to eradicate rheumatic disorders contributes

to high incidence of heart disease during pregnancy -

reference centers estimate that up to 4.2% of

pregnant patients are affected, eight times more

when compared to international estimates (Tedoldi,

2009).

Early diagnosis of heart disease during

pregnancy depends a great deal on the understanding

of adaptive physiological alterations during

pregnancy. That assessment is part of the routine in

prenatal care, whose main actions focus on

establishing the distinction between adaptive

physiological processes and pathological conditions

associated to pregnancy. In that context, it is known

Miranda Araújo M., Silveira Nogueira Reis Z., Baracho Porto R., Villas Freire C., Brito Goulart V., A. Fernandes F., Oliveira R. and Cruz-Correia R..

Auscultatory Changes Identiﬁed through Digital Stethoscope and Echocardiographic Findings Associated with Healthy Pregnancy.

DOI: 10.5220/0004637300390046

In Proceedings of the International Congress on Cardiovascular Technologies (CARDIOTECHNIX-2013), pages 39-46

ISBN: 978-989-8565-78-5

 2013 SCITEPRESS (Science and Technology Publications, Lda.)

that the common signs and symptoms in regular

pregnancy may simulate those of heart diseases and,

on the other hand, diagnosing these diseases may

become difficult due to the several transitory and

adaptive physiological hemodynamic changes

during pregnancy (van Mook, 2005).

Heart auscultation is a highly important clinical

tool in diagnosing heart disease (Chizner, 2002);

(Chizner, 2008). In pregnant patients, it can allow

for the early detection of maternal heart disease, as

well as timely interventions that can prevent these

conditions to evolve during the pregnancy, partum

and postpartum periods. However, this detection is

still a challenge for professionals that work directly

in prenatal health care. It is estimated that internal

medicine and family practice physicians were able to

recognize only 20% of the most common heart

sounds and murmurs that could be diagnosed using a

stethoscope (Mangione, 1997).

Instruments that allow for better quality in heart

auscultation, analyzing and classifying sounds with

resources that enhance the human hearing capacity

and at the same time make it easier to detect normal

and abnormal heart sounds, are a great asset to

tracking and diagnosing maternal heart diseases.

1.2 The Origin and Meaning of Heart

Sounds

The vibrations generated by the heart and the great

vessels travel to the surface of the human body. The

sounds and murmurs produced in the cardiovascular

system correspond to sound phenomena with

specific characteristics of intensity (loudness),

frequency (pitch) and quality (timbre). Most sounds

relevant to the heart auscultation process are below

the 20-500 Hz frequency, a range with a relatively

high audibility threshold (Pazin-Filho, 2004).

The origin of human heart sounds is attributed to

a set of hemodynamic changes that occur during the

cardiac cycle. A rhythmic sequence of pressure

variation in the heart chambers, propelled by

myocardium contractions, makes the heart valves

move (Hanifin, 2010).

The first heart tone (B1) features two main sound

components, originated at the atrioventricular

valves: the first one is comprised of intense high-

frequency vibrations caused by the closure of the

mitral valves (M1); while the second one, is also

comprised of high-frequency vibrations caused by

the closure of the tricuspid valve (T1), which takes

place 30 ms later on average. The second tone (B2)

reflects the blocking of the semilunar aortic (A2)

and pulmonary (P2) valves. Most normal individuals

produce a sole sound during expiration, while during

inspiration it is possible to observe its physiological

splitting (Pazin-Filho, 2004).

It is critical to identify and characterize B1 and

B2 in the auscultatory process, since they define the

cardiac cycle intervals: the ventricular systole

interval and the beginning of ventricular diastole,

respectively. The systolic interval is shorter than the

diastolic one, but the difference becomes less

noticeable as the cardiac frequency is elevated.

(Hanifin, 2010) The first tone is more intense in the

apex and the lower-left sternal border, while the

second tone tends to be more prominent at the base.

(Chizner, 2008)

Heart murmurs are the set of much longer

vibrations that arise when the blood changes its flow

standard and becomes turbulent (Hanifin, 2010).

Turbulence may occur as a result of an excessive

increase in blood flow speed in relation to the

dimensions of the structures through which it runs

(Shaver et al., 1985).

Changes of sound intensity in B1 and B2, the

occurrence of B3 and B4, noise, murmurs, clicks,

gallops, place of auscultation and radiation, the

starting point of the cardiac cycle, are all sound

variations used in cardiac semiology to diagnose

cardiovascular diseases (Chizner, 2002).

1.3 The Role of the Stethoscope

The stethoscope is an instrument designed for

capturing and conducting vibrations from the heart

and vascular structures that reach the surface of the

chest and the hearing device of the examiner,

reducing environment noise and helping to diagnose

several heart diseases. (Segall, 1963); (Kindig and

, 1982); (Kindig, 1982). The stethoscope is

relatively inexpensive and widely available, and it

still remains a qualitative and subjective method of

evaluating heart sounds, murmurs and other cardiac

noises. (Zuhlke et al., 2012)

More recently, electronic stethoscopes have

become available, equipped with sound

amplification and environment noise reduction

technology, featuring display, recording, storage and

reproduction of these sounds, as well as transmission

capacity (Hedayioglu et al., 2007); (Tavel, 2010);

(Tavel, 2006).

The signs captured electronically through this

digital auscultation system may be submitted to

objective numeric and visual analysis, transmitted to

local remote places or stored in medical records

(Dahl et al., 2002). Analysis of signs constitutes a

promise that may contribute to clinical application,

CARDIOTECHNIX2013-InternationalCongressonCardiovascularTechnologies

as in the assessment of aortic stenosis and the

classification of physiological murmurs (Tavel and

Katz, 2005). Its real importance and advantages in

comparison to traditional stethoscopes are still to be

determined; however, digital heart auscultation may

potentially tackle current challenges in teaching

heart auscultation.

1.4 Maternal Heart Auscultation and

Physiological Changes of

Pregnancy

The profound cardiovascular adaptive changes that

pregnant women undergo may seriously affect heart

auscultation (Hanifin, 2010). The hyperkinetic

hemodynamic state and low blood viscosity are

characteristic to pregnancy and favor the occurrence

of low-intensity systolic murmurs in over 95% of

pregnant women (Teixeira, 2010). On the other

hand, a similar situation may be observed in other

hyperkinetic conditions such as fever, anemia,

exercise, excitement and hyperthyroidism. In

healthy pregnancies, a low murmur intensity (1- 2/6

in the Levine scale) is frequently observed in the

beginning or the middle of the systole, increasing-

decreasing, many times with a musical, vibrating or

rumbling quality. It is more audible over the

pulmonary area or the medium-left sternal border,

but it may also be heard on the apex or the aortic

area. It is frequently accompanied by an

physiological splitting of S2 (Stout and Otto, 2007);

(Tavel, 1977).

Blood volume increases during pregnancy to

facilitate the delivery of nutrients and oxygen to the

fetus, however, the increase in plasma volume

exceeds the increase in red blood cell mass resulting

in a state of hemodilution with lower average

hemoglobin and hematocrit concentrations

(Chapman et al., 1998). This physiological anemia

tends to be more intense in the second trimester

(Teixeira, 2010), when the systolic murmur is

accentuated (Kaaja and Greer, 2005).

A normal pregnancy also causes frequent tone

(B1 and B2) hyperphonesis, B1 split and the

occurrence of B3 (Silversides, 2007). Diastolic

murmurs during pregnancy are normally associated

with anatomic heart injury (Stout and Otto, 2007);

(Tedoldi, 2009).

Echocardiogram shows left ventricular

hypertrophy with 50% increase muscle mass at full

term. Hypertrophy is eccentric, similar to the one

acquired through physical exercise. An increase may

be observed in the diameter of the mitral, tricuspid

and pulmonary valves. The aortic ring does not

dilate (Campos, 1993). With the cardiac overload

from the great increase in blood volume caused by

pregnancy, this period is particularly prone to show

heart diseases that were previously asymptomatic or

aggravate pre-existing ones (Fujitani and Baldisseri,

2005).

The main goal of this study was to describe

hemodynamic and auscultatory changes in normal

pregnant women detected by digital auscultation

system and to compare them to those of non-

pregnant women. This research also aimed at

creating a library of heart sounds, clinical data and

echocardiogram images obtained during auscultation

of healthy pregnant women, which may be used to

teach heart auscultation and analysis of signs.

2 METHODOLOGY

This is a cross-sectional study in humans, performed

in a Brazilian university hospital. The Ethics

Committee of the institution approved the study and

all the volunteers signed a letter of consent.

2.1 Research Subjects

From January 2012 to April 2013, 30 healthy

pregnant women, in the second trimester of

pregnancy and 30 healthy non-pregnant women,

aged 18 to 40 years old, without any signs or

symptoms of cardiovascular disease or anemia,

treated at the Habitual Risk Prenatal and General

Gynecology Clinic at Hospital das Clínicas of

Universidade Federal de Minas Gerais, were

selected by convenience sample, according to pre-

established eligibility criteria.

Exclusion criteria were poor quality of the

recorded sound signal, presence of cardiac

abnormalities detected by Doppler echocardiography

or anemia (hemoglobin concentration < 10,5mg/dL

(Rasheed et al., 2008) in pregnant women and

12mg/dL in non-pregnant women).

Four women were excluded from the study, one

pregnant woman due to moderate mitral

regurgitation and three non-pregnant women, due to

loss or poor quality of the recorded signal.

Therefore, 56 women, (29 pregnant and 27 non-

pregnant) were included for the statistical analysis.

2.2 Clinical Evaluation and

Complementary Exams

In addition to the routine obstetric consultation, an

experienced cardiologist performed a clinical and

AuscultatoryChangesIdentifiedthroughDigitalStethoscopeandEchocardiographicFindingsAssociatedwithHealthy

Pregnancy

cardiac evaluation with all pregnant women. Healthy

women were also submitted to a specific cardiac

evaluation. During the exam, the specialist carried

out auscultation and described every heart sound

change detected. That evaluation has become the

gold standard for describing abnormal cardiac sound

findings in both groups. On the same day, their

blood pressure was measured with a manual

sphygmomanometer in the right arm, with the

women sitting.

A hemoglobin dosage was achieved in all

pregnant subjects that did not do a blood test

recently. A complete two-dimensional (2-D)

Doppler echocardiography examination was

performed in each participant at the time of

enrollment to ensure normal cardiac structure and

function.

2.3 Digital Auscultation

In order to perform the digital auscultation with

simultaneous recording of the heart sounds, an

electronic stethoscope (Littmann

Model 3200, 3M)

was used. A touchscreen laptop (ASUS EEE PC

T101MT) was used to capture the heart sounds

wirelessly via Bluetooth technology, storing the

sound library and clinical data.

The technique used for auscultation of heart

sounds with the digital system was the same used in

the routine cardiac examination. With women sitting

and reclined, and afterwards in the left lateral

decubitus, the recording sequence took place in the

classic areas of auscultation. For each of these areas

, 2

, 4

and 5

) the recording lasted for about 15

seconds.

The electronic information system used to store

clinical data and heart sounds was developed by the

DigiScope project team (Pereira et al., 2011).

2.4 Echocardiographic Protocol

Cardiac ultrasound examinations were performed

with the women in the left lateral decubitus position

with an M-Turbo portable ultrasound machine

(SonoSite, Bothwell, WA, USA) equipped with 3-5

MHz phased-array transducers. A complete two-

dimensional (2-D) echocardiographic Doppler

evaluation was performed in each participant at the

time of enrollment to ensure normal cardiac

structure and function. The study protocol included

imaging of the LV from standard parasternal long-

and short- axis views and from apical four- and two-

chamber views. Qualitative access of mitral,

tricuspid, aortic, and pulmonary valve competence

by pulsed and color-flow Doppler mapping was

made. In order to assess LV systolic function, 2-D-

directed M-mode tracing of the LV minor axis

between the papillary muscle tips was recorded.

order to determine LV diastolic function, mitral

inflow was sampled by pulsed Doppler from the

apical four-chamber view and analysis of the pulsed

tissue Doppler of the mitral angle. All study images

were video-recorded for further analysis.

2.5 Statistical Method

In order to estimate the sample size, we used the

GPower 3.1.3 statistical software, with a standard

significance and test power α=5% and β=80%,

respectively. Bearing in mind that the expected

prevalence of healthy pregnant subjects with some

functional changes of heart auscultation is 95%

(Tedoldi, 2009), and that the expected prevalence of

functional auscultation sounds of the general

population is 77.9% (Bloch and Jaussi, 2001), these

two populations are expected to be differentiated

with at least 52 women, 26 healthy non-pregnant

women and 26 healthy pregnant subjects.

The variables chosen to compare the both groups

in the study were the clinical findings of the heart

auscultation and the Doppler echocardiographic

abnormalities, both observed by the same

cardiologist.

For the statistical analysis, each variable was

statically described and compared between groups of

study. For quantitative variables, the minimum and

maximum values were observed and means, medians

and standard deviations were calculated. The mean

values obtained in the two groups were compared by

independent samples t-test for normally distributed

variables and the Mann-Whitney U test for not

normally distributed ones. Proportions were

compared using chi-square and/or Fisher's exact test.

The statistical software used was SPSS ® 21.0 for

Macintosh (2013).

The significance level was established at 5%.

3 RESULTS

Some demographic and clinical characteristics of the

study and control groups are summarized in Table 1.

The blood pressure levels in pregnant subjects were

shown to be lower than the ones from the control

group. Changes identified in the clinical auscultation

happen more frequently in pregnant women, except

for the B2 split.

Women aged from 19 to 40 years old, mean age

CARDIOTECHNIX2013-InternationalCongressonCardiovascularTechnologies

(SD) of 29 (5.5) years and the median was 29 years.

With regard to pregnant women, age ranged from 19

and 36 years old, mean (SD) of 27 (5) years and the

median was 27. In non-pregnant women, age ranged

from 21 to 40 years old, mean (SD) age was 30 (5.4)

years and median was 31 years (Table 1).

Weight of the patients ranged from 45.4 kg to

101.5 kg, with a mean (SD) weight of 65.6 (12.78)

kg and a median of 62.5 kg. In pregnant women,

weight ranged from 45.4 kg to 93.3 kg with a mean

(SD) of 67 (12.39) kg and a median of 66 kg and in

non-pregnant women it ranged from 49.3 kg to

101.5 kg, with a mean (SD) weight of 64.1 (13.25)

kg and a median of 62kg.

Height ranged from 1.47m to 1.77m, mean (SD)

height was 1.61 (0.065) and median was 1.62m. In

pregnant women height ranged from 1.47 to 1.77m,

the mean (SD) height was 1.60 (0.067) and median

1.60 m. In non-pregnant women, height varied from

1.50 to 1.72m, mean (SD) was 1.62 (0.062) and

median 1.63m.

Considering all women, mean body mass index

(BMI) was 25 kg/m2 (ranging from 17.7 - 40.3

kg/m2; Median: 24.3 kg/m2). In pregnant women,

the mean value for body mass index (BMI) was 26

kg/m2 (ranging from 18.3 - 40.4 kg/m2; Median:

25.7 kg/m2). In non-pregnant women, the mean

value for body mass index (BMI) was 24.3 kg/m2

(ranging from 17.7 - 36.5 kg/m2 and median 22.6

kg/m2).

No significant differences were found when

comparing the two groups regarding weight, height

and body mass index.

The group of pregnant women had median

(minimum-maximum) values of systolic blood

pressure, and diastolic blood pressure of 102 (90-

128), and 68 (50-78), respectively. Concerning the

mean arterial pressure, it’s mean (SD) value was

79.4 (6.5). The control group had median

(minimum-maximum) values of systolic blood

pressure and diastolic blood pressure of 113 (90-

130) and 80 (60-102), respectively, and the mean

(SD) mean arterial pressure was 89.6 (9.2). Systolic

blood pressure, diastolic pressure and systolic

murmur were seen to have significantly higher

values in the control group (Table 1).

The chance (95% CI) to detect the systolic

murmur was estimated as 3.2 (1.1-9.7) times higher

in pregnant than in non-pregnant women. The

chance (95% CI) to detect B1 hyperphonesis was

13.4 (2.7-67.3) times higher; while for B1 split it

was 20.6 (4.8-88) times higher and for B2

hyperphonesis it was 9.8 (2.8-34.1) times higher.

Regarding Doppler echography, the occurrence

of physiological valvular regurgitation was similar

in the study and control groups. Pulmonary

regurgitation, 25% versus 18.5% (p=0.561);

tricuspid regurgitation, 86.2% versus 92.6%,

(p=0.671); and mitral regurgitation, 72.4% versus

74.1% (p=0.889), respectively.

In healthy pregnant subjects, no significant

association was found among the occurrence of heart

murmur with the digital auscultation system and the

corresponding echocardiogram alterations, mitral

murmur versus mitral regurgitation (p=0.675;

tricuspid murmur versus tricuspid regurgitation,

(p=1.000) and pulmonary murmur versus pulmonary

regurgitation (p=1.000). Even though 20.7% of

pregnant women showed aortic murmur, none of

them had corresponding changes in the

echocardiogram.

4 DISCUSSION

Heart auscultation by means of a stethoscope has

been historically considered a symbol of medical

care.

Table 1: Clinical characteristics, regarding groups of study.

Caracteristics

Healthy pregnant women

(n=29)

Control group

(n=27)

p-value

Mean age (years) (SD) 26.8 (5.0) 30 (5.4) 0.011 *

Mean weight (kg) (SD) 67.0 (12.4) 64.1 (13.3) 0.402 *

Mean height (m) (SD) 1.6 (0.06)

1.6 (0.06)

0.249 *

BMI (kg/m

) median/range 25.7 / 22.1 22.6 / 18.8 0.129 **

Systolic blood pressure (mmHg) median/range 102 / 38 113 / 40 0.009 **

Diastolic blood pressure (mmHg) median/range 66 / 28 80 / 42 <0.001 **

Mean mean arterial pressure (mmHg)

(SD)

79.4 (6.5) 89.6 (9.2) <0.001 *

Systolic murmur n (%) 20 (69.0) 11 (40.7) 0.034

B1 hyperphonesis n (%) 15 (51.7) 2 (7.4) <0.001

B1 split n (%) 26 (89.7) 8 (29.6) <0.001

B2 hyperphonesis n (%) 20 (69.0) 5 (18.5) <0.001

B2 split n (%) 27 (93.1) 27 (100) 0.492

Mean arterial pressure: (Systolic+2Diastolic)/3 *T-mean Test, ** Mann-Whitney Test,

Chi-square Test,

Fisher Test

AuscultatoryChangesIdentifiedthroughDigitalStethoscopeandEchocardiographicFindingsAssociatedwithHealthy

Pregnancy

Even though complementary tests are currently

fundamental to diagnose cardiovascular diseases, the

clinical semiology associated with anamnesis is still

the first step in a complete and accurate

cardiovascular evaluation. During prenatal care, the

auscultation of heart sounds is especially important

to track heart diseases, which are serious pregnancy

complications and a relevant cause of maternal

death.

This study has shown that heart sounds change

significantly in the second trimester of pregnancy -

describing the most relevant adaptive changes.

Echocardiography performed in all studied cases

was critical to discard possible unsuspected diseases.

In addition, a specialist allowing us to infer that

these changes have a physiological nature performed

a complete cardiovascular examination. And even

though they may be mistaken for heart disease

sounds, they are not enough to justify additional

routine tests such as echocardiography for those

cases. This is not a recent notion. In order to avoid

making inappropriate use of echocardiography in

pregnant women showing heart murmur, it is

recommended to limit exam requests only for those

patients with a history of an underlying heart

disease, clear heart symptoms, systolic murmur

equal or over 3/6 in the Levine scale or diastolic

murmur (Bonow et al., 2008) (Stout and Otto, 2007).

Significant findings on echocardiography have

also been reported in other studies. In a longitudinal

Doppler echocardiographic study, in four gestational

periods and the puerperium, a progressive increase

in the prevalence of physiologic tricuspid and

pulmonary regurgitation, as well as the transient

development of trivial mitral regurgitation have been

observed (Campos, 1993). In another study, 79% of

women were clinically thought to have benign flow

murmurs during pregnancy, and the

echocardiographic and Doppler results were normal

in all of them (Mishra, 1992).

However, one of the limitations in the present

approach is related to the design of the transversal

study. It is known that with a longitudinal analysis,

in which a group of pregnant subjects could be

monitored throughout the pregnancy and

puerperium, a more complete and temporary view of

the intense physiological changes through heart

auscultation are more likely to occur. In order to

overcome the current impossibility of the approach,

we chose the second trimester of pregnancy to

perform the evaluation, since that is when blood

volumes hit their highest level, causing a significant

hemodilution and a characteristic hyperdynamic

state associated with the changes in sounds.

But it can still be considered an innovative

evaluation if we consider the fact that a digital

system was used, allowing us to store each pregnant

subject's heart sounds, subsequently to reevaluate

auscultations as often as necessary and to classify

them properly. We hope that the library of sounds,

images and clinical data created with the study can

contribute to the education of health care

professionals, providing better resources to detect

heart diseases. Similarly, the digital sonograms

stored may be used in establishing the difference

between heart disease standards through a study

involving the analysis of digital signals in order to

compare sonograms stored with the ones generated

by heart diseases.

Another important asset was to set up a

multidisciplinary group of medical informatics,

consisting of medical and information technology

researchers from different areas. This variety of

professionals is essential for further analysis, as it

brings important computer tools to help solve some

of the greatest challenges in medicine.

Since Brazil is a country of continental

proportions, and part of the population lives in areas

with no access to health care or specialized health

professionals, the digital heart auscultation

technology would help combine information

technology and the promotion of health care,

shortening distances between isolated populations

and large urban centers. UFMG is connected to the

University Telemedicine Network through Tele-

health System (Ribeiro, 2010), with 817 connection

points available in the state of Minas Gerais

(www.telessaude.hc.ufmg.br), with a potential of

using the results from this investigation to achieve

the goals of telemedicine. With a future perspective

yet to be planned, digital heart auscultation

technology can become part of the propedeutics of

heart diseases in teleconsultations, validating these

findings in a large number of subjects. Early

diagnosis of heart disease during pregnancy using

transmitted digital signs could be a potential

advantage of this technology.

5 CONCLUSIONS

Digital heart auscultation performed in healthy

pregnant subjects was able to detect frequent and

numerous changes and results confirm the

importance of understanding the physiological

changes that take place during pregnancy. The

normal echocardiogram in all healthy pregnant

women with heart murmur indicates that such test

CARDIOTECHNIX2013-InternationalCongressonCardiovascularTechnologies

has limited applicability for healthy pregnancy, only

in cases of suspicion of a heart disease or when it

does occur.

ACKNOWLEDGEMENTS

We would like to thank Hospital das Clínicas of

Universidade Federal de Minas Gerais, CAPES and

FAPEMIG for the financial support.

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CARDIOTECHNIX2013-InternationalCongressonCardiovascularTechnologies