A comparative study on the effect of music therapy alone and a combination of music and yoga therapies on the psycho-physiological parameters of cardiac patients posted for angiography

Abstract

Background and Objectives: Patients undergoing cardiac catheterization and coronary angiography often experience high levels of anxiety and physiological disturbances. Music therapy and music interventions have been found to be effective in bringing down the anxiety and reducing the physiological disturbances for these patients. However, the efficacy of combination of music and yoga therapies for pre-procedural anxiety and physiological disturbances needs to be studied. We aimed in this study to compare the effect of music therapy with the combination of music and yoga therapies to impact the psycho-physiological responses like anxiety, blood pressure, pulse rate and respiratory rate of patients who were posted for coronary angiography Material and Methods: A total of 45 patients who were posted for coronary angiography were included in the study and randomly divided into three groups. Music therapy group(n=16) received music listening intervention in the form listening to pre-recorded, patient-preferred, relaxing raga improvisational music for 15 minutes 1) on the previous day of angiography and 2) 15 minutes before being taken to the catheterization lab on the day of the angiography. The combination of music and the yoga group received both music therapy and yoga therapy in the form of pranava pranayama together for 15 minutes. The control group received only the standard medical treatment. The state of anxiety was measured by a five point single item Likert scale and the physiological measures such as systolic blood pressure (SBP), diastolic blood pressure (DBP), pulse rate (PR) and respiratory rate (RR) were also recorded for the study Results: Both music therapy alone and the combination of music and yoga therapies resulted in within the group significant reduction in anxiety and respiratory rate and music therapy group recorded additionally significant reduction in SBP, DBP and PR scores during the period of intervention. Conclusion: Our findings indicate that music therapy alone can bring down the anxiety levels and reduce the physiological disturbances of patients posted for angiography. Also, combination of music and yoga therapies can bring down the anxiety levels and improve the deep breathing pattern for these patients posted for angiography. More studies are needed to confirm these findings.

Full text

SBV Journal of Basic, Clinical and Applied Health Science - Volume 2 | Issue 4 | October - December 2018 163
A comparative study on the eect of music therapy alone and
a combination of music and yoga therapies on the psycho-
physiological parameters of cardiac patients posted for angiography
Ajmera S1,*, Sundar S1 , Amirtha Ganesh B2 , Bhavanani A.B3 , Dayanidy G3 ,
Ezhumalai G4
Original Article
1Center for Music Therapy
Education and Research
(CMTER),
2Department of Cardiology,
Mahatma Gandhi Medical
College and Research Institute,
3Center for Yoga Therapy
Education and Research
(CYTER),
4Office of the Deanery of
Research,
Sri Balaji Vidyapeeth,
(Deemed to be University),
Pillaiyarkuppam,
Puducherry-607402.
For Correspondence
*Dr. Sundar S,
Email: sumusundhar@yahoo.com
Date of
Submisssion: 29-08-2018
Acceptance: 03-10-2018
ABSTRACT
Background and Objectives: Patients undergoing cardiac catheterization and
coronary angiography often experience high levels of anxiety and physiological
disturbances. Music therapy and music interventions have been found to be effective
in bringing down the anxiety and reducing the physiological disturbances for these
patients. However, the efficacy of combination of music and yoga therapies for pre-
procedural anxiety and physiological disturbances needs to be studied. We aimed
in this study to compare the effect of music therapy with the combination of music
and yoga therapies to impact the psycho-physiological responses like anxiety,
blood pressure, pulse rate and respiratory rate of patients who were posted for
coronary angiography
Material and Methods: A total of 45 patients who were posted for coronary
angiography were included in the study and randomly divided into three groups.
Music therapy group(n=16) received music listening intervention in the form
listening to pre-recorded, patient-preferred, relaxing raga improvisational music for
15 minutes 1) on the previous day of angiography and 2) 15 minutes before being
taken to the catheterization lab on the day of the angiography. The combination of
music and the yoga group received both music therapy and yoga therapy in the
form of pranava pranayama together for 15 minutes. The control group received
only the standard medical treatment. The state of anxiety was measured by a five
point single item Likert scale and the physiological measures such as systolic blood
pressure (SBP), diastolic blood pressure (DBP), pulse rate (PR) and respiratory
rate (RR) were also recorded for the study
Results: Both music therapy alone and the combination of music and yoga therapies
resulted in within the group significant reduction in anxiety and respiratory rate and
music therapy group recorded additionally significant reduction in SBP, DBP and
PR scores during the period of intervention.
Conclusion: Our findings indicate that music therapy alone can bring down the
anxiety levels and reduce the physiological disturbances of patients posted for
angiography. Also, combination of music and yoga therapies can bring down the
anxiety levels and improve the deep breathing pattern for these patients posted for
angiography. More studies are needed to confirm these findings.
Keywords
Music, Yoga, Cardiac Catheterization, Angiogram, Anxiety
IntroductIon
Patients having acute coronary
syndrome (ACS) and waiting for the
cardiac catheterization and coronary
angiography (CAG) procedures may
experience high levels of anxiety
and stress. Long waiting time, non-
availability of psycho-social support,
first time schedule to angiography
and uncertainty about the procedural
outcome are some of the reasons why
patients in the pre-catheterization
period experience fear, anxiety and
stress. Unrelieved anxiety and stress
during this period may not only lead
to lack of co-operation by the patients.
Patients also suffer physiological
disturbances, reduced immune response
Access this article online
Quick Response Code
https://www.jbcahs.org
E-ISSN: 2581-6039
How to Cite: Ajmera S, Sundar S, Amirtha Ganesh B, Bhavanani AB, Dayanidy G, Ezhumalai G.
A comparative study on the effect of music therapy alone and a combination of music
and yoga therapies on the psycho-physiological parameters of cardiac patients posted
for angiography. J Basic Clin Appl Health Sci. 2018;2:163-8

SBV Journal of Basic, Clinical and Applied Health Science - Volume 2 | Issue 4 | October - December 2018164
Sundar
et al
: Music and yoga therapies on the psycho-physiological parameters of cardiac patients posted for angiography
and altered cardiovascular functioning like tachycardia,
increase in core body temperature, heightened blood
pressure and nausea which may directly impact the
clinical outcomes.1-3 Hence, it becomes important to
adopt a multidisciplinary strategy to minimize anxiety
and physiological disturbances of in-patients posted
for CAG. Use of complementary therapies like music
and yoga as stand- alone adjunct therapies have been
studied to be beneficial in reducing stress and anxiety
by encouraging the patients to relax, slow down the
breathing and activate the para-sympathetic system
and inhibiting the sympathetic nervous system.
4-6
However, we did not come across any study reported
so far on evaluating the eects of the combination of
yoga and music therapies as procedural support in CAG
patients.
A Cochraine systematic review which included 26
studies with the total of 2051 participants published
in the year 2013 concluded that music listening
interventions in which pre-recorded music was used by
health care and allied health care professionals reduced
significantly pre-operative anxiety in medical patients
and hence music could serve as a good alternative
option to sedatives and anti-anxiolytic drugs.5
Pranava Pranayama is slow, deep and rhythmic
breathing where emphasis is placed on making the
sound AAA, UUU and MMM while breathing out for
duration of 2 to 3 times the duration of the inhaled
breath.
6,7
It is a four part technique consisting of
lower chest breathing with the sound of AAA, mid-
chest breathing with the sound of UUU, upper chest
breathing with the sound of MMM and then the union
of the earlier three parts in a complete yogic breath
with the sound of AAA, UUU and MMM.
Previous studies by Bhavanani and colleagues
have reported that pranayama-based breathing and
relaxation is eective in reducing blood pressure and
stress6-8. It was studied in hypertensive and diabetic
patients and found to reduce heart rate and SBP within
five minutes of the practice as well as reduce stress and
anxiety over 12 weeks of training. This was attributed
to normalization of autonomic cardiovascular rhythms
as a result of increased vagal modulation and/or
decreased sympathetic activity and improved baroreflex
sensitivity.
It has been reported that the eects of pranava
relaxation in supine position are strikingly similar to the
deep relaxation technique (DRT) popularized by Swami
Vivekananda Yoga Anusandhana Samsthana (SVYASA)
University, Bangalore.
9
Studies from SVYASA have
reported that DRT improves sustained attention and
reduces the state of anxiety while reducing cardiac
sympathetic activity.9,10
We conducted this trial to compare the eect of
music therapy with that of the combination of music and
yoga therapies on the psycho-physiological parameters
like anxiety, systolic blood pressure, diastolic blood
pressure, pulse rate and respiratory rate in patients
posted for coronary angiography as no studies are
reported on this combination intervention strategy.
We used pre-recorded, patient-preferred, instrumental,
Indian classical music as a music listening intervention.
Though music therapists provide mostly customized
live musical experiences in therapy sessions based
on the context in which they are administering the
therapy, it is not totally uncommon for qualified music
therapists working in hospital settings to use music
listening interventions using pre-recorded music in
their research studies.
11,12
For yoga therapy, we used
pranava pranayama breathing technique.
MaterIal and Methods
The study was approved by the Institutional Human
Ethics Committee of Mahatma Gandhi Medical College
and Research Institute, Pondicherry. This open label,
three-arm, randomized controlled study was carried
out for a period of 4 months in the catheterization
laboratory attached to the Department of Cardiology
of the hospital by a qualified music therapist. All
patients in the age group of 30 to 65 who were posted
for angiography for the first time and gave written
informed consent, understood the local language
and be able to take instructions were enrolled for
the study. Patients who received any psychiatric
treatment or anxiolytic medication, hard of hearing,
having a diagnosis of cerebrovascular accident (CVA) or
scheduled for an emergency angiogram were excluded
from the study.
For sample size calculation, we assumed a type 1
error of 0.05 (95% confidence interval) by keeping α
= 0.01 and type II error of β = 0.02 (a power of 80%).
The sample size computed was 30 in each group with
a total of 90.
In total, 45 patients who fulfilled the inclusion
criteria were randomly assigned by a computer
assisted method in which random numbers were
generated in the system and accordingly the patients
were distributed into the three groups with 16 in the

SBV Journal of Basic, Clinical and Applied Health Science - Volume 2 | Issue 4 | October - December 2018 165
Sundar
et al
: Music and yoga therapies on the psycho-physiological parameters of cardiac patients posted for angiography
music therapy group, 14 in the combination of music
and yoga therapy group and 15 in the control group.
The random allocation sequence was concealed in
sealed opaque covers and kept in the cardiothoracic
and vascular surgery (CTVS) ward. The baseline
characteristics indicated that the three groups were
identical and hence could be compared. The patients
participating in the study were informed about the
study procedure and were free to withdraw from the
study at any point of time they wanted. There were
two interventions for both the groups. The first was on
the previous day to angiography and the second was
on the day of the angiography. The first intervention
was administered in the CTVS ward and the second
intervention was administered in the waiting area of
the catheterization laboratory.
Participants in the music therapy group listened to
preferred, instrumental, Indian classical, relaxing pre-
recorded improvisational raga music for 15 minutes on
the day 1 and also on the day of the angiography for 15
minutes in the presence of a qualified music therapist.
In the combination of music and yoga therapy group,
the patients were engaged in yogic breathing for 7.5
minutes by a qualified yoga therapist followed by 7.5
minutes of music listening intervention as was in the
music group. For both the interventions, the base line
and the end of study measures were recorded. Anxiety
was measured by a single item five point Likert scale
having the options from “no anxiety, mild anxiety,
moderate anxiety, severe anxiety and extremely high
anxiety.” The Likert scale was used as it is useful
to record the anxiety levels easily and quickly and
also when the researchers have very short time or
psychometric tool space and need to reduce the burden
on the patients waiting for an invasive interventional
procedure evoking high levels of anxiety.
13
Blood
pressure and pulse rate were recorded by electronic
sphygmomanometer.
Distribution of data for the study was checked by
performing normality tests and data was found to be
normally distributed. Hence data was analysed by
paired t tests, ANOVA and repeated measures ANOVA.
Wilcoxon test and Friedman’s test was conducted for
anxiety.
Table 1: Comparison of pre and post measures of selected psycho-physiological parameters in all the three groups control (n=15), music
(16) and music and yoga groups(n=14)
Measurement
Groups
Control (n=15) Music (n=16) Music and Yoga (n=14)
Pre
Mean± SD
Post
Mean± SD p-value Pre
Mean± SD
Post
Mean± SD p-value Pre
Mean± SD
Post
Mean± SD p-value
Day 1
SBP 117.53±12.61 114.40±10.29 0.32 133.31±18.56 127.00±19.14 0.32 131.07±27.1 127.14±20.3 0.29
DBP 71.87±12.01 70.27±9.12 0.57 80.38±6.14 76.81±8.53 0.04 80.43±14.16 77.93±12.23 0.23
PR 67.80±10.57 69.13±88.14 0.45 78.12±12.01 67.44±13.32 0.04 73.93±11.45 68.43±19.29 0.12
RR 22.67±4.19 21.40±4.70 0.13 23.93±4.26 22.07±6.02 0.04 23.93±4.27 22.07±4.75 0.02
Anxiety 0.60±0.83 0.67±0.90 0.32 0.88±0.81 0.06±0.25 0.001 0.93±0.99 0.43±0.75 0.04
Day 2
SBP 132.71±29.38 130.79±24.37 0.22 131.62±16.34 126.25±15.64 0.01 132.71±29.38 130.79±24.37 0.42
DBP 76.73±12.38 73.73±11.32 0.09 80.19±4.92 76.81±5.14 0.001 79.57±11.04 78.64±13.48 0.68
PR 73.67±11.81 69.53±9.98 0.12 76.12±11.93 71.31±10.72 0.01 76.12±14.70 71.31±13.87 0.07
RR 22.67±4.189 20.80±3.30 0.12 23.75±4.34 19.69±3.14 0.01 23.93±4.27 20.00±4.08 0.001
Anxiety 0.53±0.74 0.53±0.74 1.00 0.67±0.70 0.25±0.44 0.01 0.64±0.84 0.29±0.61 0.03

SBV Journal of Basic, Clinical and Applied Health Science - Volume 2 | Issue 4 | October - December 2018166
significantly reduced from 132 to 126, 80 to 77, 76
to 71, 23 to 19 and 0.67 to 0.25 respectively (p=0.01,
p=0.001,p=0.01, p=0.01,p=0.01). In the combination
of music and yoga therapy group, RR had marginally
reduced from 24 to 20 and anxiety was reduced from
0.64 to 0.29 and this dierences were significant
(p=0.001, p=0.03). (Table 1)
The mean levels of SBP, DBP, PR, RR and anxiety
at day1 pre, day1 post and day2 post for each group
was analysed to find the variations over these periods.
In control group, the mean reduction of SBP, DBP,
PR, RR were not significantly change in two days,
but anxiety alone was reduced from 0.6 to 0.53 and
significant (p=0.001). In music group, SBP & DBP
were not significantly changed but PR, RR and anxiety
were reduced from 78 to 69, 24 to 20 and 0.88 to 0.25
respectively.(p=0.001, p=0.01, p=0.001). In music
results
The pre and post measurement of SBP, DBP, PR,
RR and anxiety among patients who had undergone
coronary angiography were measured and tested for any
possible dierence. On day1, the level of SBP, DBP,
PR and RR remained unaltered in the control group
which received only routine treatment. In the music
therapy group, the DBP, PR and RR of the patients
had significantly reduced from 80 to 77, 78 to 67, 24
to 22 and 0.88 to 0.06 respectively (p=0,04, p=0.04,
p=0.04, p=0.001). In the combination of music and
yoga therapies group, the RR had marginally reduced
from 24 to 22 and it was significant (p=0.02). In this
group, anxiety was also significantly reduced from
0.93 to 0.43(p=0.04). On day2, the level of SBP,
DBP, PR, RR and anxiety remained unaltered in
the control group. In music therapy group, the SBP,
DBP, PR, RR and anxiety levels of the patients had
Sundar
et al
: Music and yoga therapies on the psycho-physiological parameters of cardiac patients posted for angiography
Table 2: Comparison of SBP, DBP, PR, RR and anxiety levels from baseline to day 2 post for each group.
Parameter Days of
measurement
Groups
Control Music Music and yoga
Mean ±SD p-value Mean ±SD p-value Mean ±SD p-value
SBP
pre Day1 117.53±12.60
0.367
133.31±18.56
0.15
131.07±27.12
0.42post Day1 114.40±10.29 127.00±19.14 127.14±20.33
post Day2 118.40±11.54 126.25±15.64 130.7924.37
DBP
Pre Day 1 71.87±12.01
0.382
80.38±6.14
0.07
80.43±14.16
0.39Post Day1 70.27±9.12 76.81±8.52 77.93±12.23
Post Day2 73.73±11.32 76.81±5.14 78.64±13.48
PR
Pre Day1 67.80±10.51
0.775
78.12±12.01
0.001
73.93±11.45
0.14Post Day 1 69.13±8.85 67.44±13.32 68.43±10.28
Post Day2 69.53±9.97 69.53±9.97 69.57±13.86
RR
Pre Day1 22.67±4.19
0.242
23.75±4.34
0.01
23.93±4.26
0.001Post Day1 21.40±4.70 23.00±6.02 22.07±4.74
Post Day2 20.80±3.30 19.69±3.14 20.00±4.08
Anxiety
Pre Day1 0.60±0.83
0.001
0.88±0.80
0.001
0.94±0.00
0.001Post Day 1 0.67±0.90 0.06±0.25 0.43±0.76
Post Day2 0.53±0.74 0.25±0.45 0.29±0.61

SBV Journal of Basic, Clinical and Applied Health Science - Volume 2 | Issue 4 | October - December 2018 167
Sundar
et al
: Music and yoga therapies on the psycho-physiological parameters of cardiac patients posted for angiography
with yoga group, SBP, DBP & PR were not significantly
changed in two days but RR & anxiety were changed
from 24 to 20 and 0.94 to 0.29 respectively.(p=0.001,
p=0.001).(Table 2).
A post-hoc test for PR and RR for music group and
RR for music with yoga group was administered to
find out the possible combinations of eect occurred
during these two days. Pulse rate was significantly
reduced on day1 post assessment and it was significant
(p=0.01). RR was significantly reduced on second
day post assessment compared to day1 pre assessment
(p=0.04). In music with yoga group, RR was reduced
significantly from day1 pre compared to day1 post
(p=0.04) and also day1 pre compared with day2 post
(p=0.001). (Table 3).
dIscussIon
Music listening has been consistently reported to bring
down anxiety in patients through stress reducing
eects5,14-16 and more specifically in cardiac patients as
per the latest Cochraine review of patients with coronary
heart disease.
17
The results of our study is in consonance
with these findings. Another mechanism put-forth for
music listening to bring down anxiety is that music can
help people focus their attention away from distressing
situations and generate positive moods and emotions
which in turn reduces the anxiety levels.17 Similarly,
the music listening interventions also stabilized the
physiological responses by reducing the SBP, DBP,
PR and RR . Both the reduction of anxiety and the
regularization of the physiological responses could
also be attributed to the music listening intervention
suppressing the sympathetic activity leading to reduced
adrenergic activity and regulation of the autonomic
cardiovascular rhythms.18,19
For this study, the researcher prepared a play list of
Indian classical music in the form of raga improvisation
from which the patient chose one musical piece for the
music listening intervention. All the improvisational
pieces had the common characteristics of slow tempo,
soft timbre (flute), simple melodic phrases in the same
octave without sudden jumps of octaves and with low
emotional intensity. All the patients participated in the
study also were belonging to the same ethnic group.
In our study, the combination of music and the
pranava pranayama intervention also consistently
reduced the anxiety of patients posted for angiography
during the period of intervention. The mechanism for
reduction of stress and anxiety by pranava pranayama is
also the same as that for music. The pranava pranayama
intervention also improved the deep breathing pattern
of the patients facilitating relaxation. The findings
of our study indicated that music therapy as a stand-
alone adjuvant therapy was able to reduce the anxiety
of the patients and also stabilized the physiological
responses. Also, the combination of music and yoga
therapies could produce the desired result of reducing
the anxiety and enhancing deep breathing thereby
facilitating relaxation.
An important limitation of the study was that
though the sample size calculated was 30 in each group,
Table 3: Post-hoc test for music and music with yoga group
Group Parameter Between pairs Mean diff
95% CI for difference p-value
Lower Upper
Music PR
Pre day 1& post day 1 10.68 2.16 19.21 0.01
Pre day 1 &post day 2 6.81 -0.53 14.16 0.07
Post day 1 & post day 2 -3.87 -11.51 3.76 0.58
Music RR
Pre day 1& post day 1 0.750 -1.55 3.05 1.00
Pre day 1 &post day 2 4.06 0.210 7.92 0.04
Post day 1 & post day 2 3.31 -1.23 7.86 0.21
Music with Yoga RR
Pre day 1& post day 1 1.85*0.040 3.67 0.04
Pre day 1 &post day 2 3.92*1.41 6.45 0.001
Post day1 & post day 2 2.07 -0.29 4.44 0.09

SBV Journal of Basic, Clinical and Applied Health Science - Volume 2 | Issue 4 | October - December 2018168
5. Keegan L. Therapies to reduce stress and anxiety. Crit Care Nurs
Clin North Am. 2003;15:321-7
6.
Bradt J, Dileo C, Shim M. Music interventions for preoperative
anxiety. Cochrane Database Syst Rev. 2013;(6) :CD006908
7.
Bhavanani AB, Madanmohan, Sanjay Z, Vithiyalakshmi L.
Immediate cardiovascular eects of pranava relaxation in patients
of hypertension and diabetes. Biomed Hum Kinet.2012; 4:66-9.
8.
Bhavanani AB, Madanmohan, Sanjay Z, Basavaraddi IV. Immediate
cardiovascular eects of pranava pranayama in hypertensive patients.
Indian J Physiol Pharmacol. 2012;56:273-8.
9.
Sharma VK, Trakroo M, Subramaniam V, Rajajeyakumar M,
Bhavanani AB, Sahai A. Eect of fast and slow pranayama on
perceived stress and cardiovascular parameters in young health-
care students. Int J Yoga 2013;6:104-10
10.
Vempati RP, Telles S. Yoga based guided relaxation reduces
sympathetic activity in subjects based on baseline levels. Psychol
Rep. 2002; 90:487-94.
11. Aldridge K. The use of music to relieve pre-operational anxiety in
children attending day surgery. Australian J Music Ther.1993;4:17.
12.
Palmer JB, Lane D, Mayo D, Schluchter M, Leeming R. Eects
of music therapy on anesthesia requirements and anxiety in
women undergoing ambulatory breast surgery for cancer diagnosis
and treatment: A randomized controlled trial. J Clin Oncol.
2015;33:3162-8.
13. Davey HM, Barratt AL, Butow PN, Deeks JJ. A one-item question
with a Likert or visual analog scale adequately measured current
anxiety. J Clin Epidemiol. 2007;60:356-60.
14.
Khemka SS., Rao NH, Nagarathna R. Immediate eects of two
relaxation techniques on healthy volunteers. Indian J.Physiol.
Pharmacol. 2009; 53:67-72.
15. Thoma MV, La Marca R, Brönnimann R, Finkel L, Ehlert U, Nater
UM. The eect of music on the human stress response. PLoS One.
2013; (8):e70156.
16. Ventura T, Gomes MC, Carreira T. Cortisol and anxiety response to
a relaxing intervention on pregnant women awaiting amniocentesis.
Psychoneuroendocrinology. 2012 ;37:148-56
17.
Bradt J, Dileo C, Potvin N. Music for stress and anxiety
reduction in coronary heart disease patients. Cochrane Database
Syst Rev. 2013 Dec 28;(12):CD006577
18.
Nilsson U. The eect of music intervention in stress response
to cardiac surgery in a randomized clinical trial. Heart Lung.
2009;38:201–7.
19.
Gillen E, Biley F, Allen D. Eects of music listening on adult
patients’ pre-procedural state anxiety in hospital. Int J Evid Based
Healthc. 2008;6:24-49.
the required number of samples were not registered in
the cardio-vascular ward for angiography during the
entire study period of 4 months and in total only 45
patients could be recruited for the study.
conclusIon
Music therapy interventions are beneficial to reduce
anxiety and physiological disturbances in patients
undergoing coronary angiography. Combination
of music and yoga therapies can reduce anxiety
and regularize breathing patterns in these patients.
However, more studies are needed to confirm these
findings with the combination of these music and yoga
treatment strategies.
conFlIcts oF Interest
None
acknowledgeMents
We thank Mrs. Bhuvaneswari Ramesh, Tutor, CMTER
for her valuable assistance during the study period
References
1.
Woodyard C. Exploring the therapeutic eects of yoga and its ability
to increase quality of life. Int J Yoga. 2011;4:49-54.
2.
Scott A. Managing anxiety in ICU patients: the role of pre-operative
information provision. NursCrit Care. 2004;9:72-9.
3.
Delewi R, Vlastra W, Rohling WJ, Wagenaar TC, Zwemstra
M, Meesterman MG et al. Anxiety levels of patients undergoing
coronary procedures in the catheterization laboratory. Int J Cardiol.
2017;228:926-30.
4.
Pritchard MJ. Identifying and assessing anxiety in pre-operative
patients. Nurs Stand. 2009;23:35-40.
Sundar
et al
: Music and yoga therapies on the psycho-physiological parameters of cardiac patients posted for angiography