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Mitral and Tricuspid Valve Closure
in Congenital Heart Disease
SELWYN MILNER, M.B.B.CH., F.C.P.(S.A.), RICHARD A. MEYER, M.D.,
ALEX W. VENABLES, M.D., M.R.C.P., JOAN KORFHAGEN, ARDMS,
AND SAMUEL KAPLAN, M.D.
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SUMMARY Echocardiography was used to evaluate mitral and
tricuspid valve closure in patients 1 day to 20 years of age. When
possible, simultaneous phonocardiograms were obtained. The
difference in time between the Q wave of the electrocardiogram and
mitral closure and between Q and tricuspid closure was designated
the delta value (A). Four groups of patients were assessed: 1) normals
(40), secundum atrial septal defect (ASD) (10), mitral valve prolapse
syndrome (Barlow's syndrome) (13), pulmonary hypertension (12),
and pulmonic stenosis (6); 2) Ebstein's anomaly (10); 3) transposition of the great vessels (15); 4) right bundle branch block (RBBB)
(25). Ten patients with surgically induced right bundle branch block
were studied by phonocardiography alone.
Group I had delta values of 50 msec or less (-5 to 50 milliseconds)
and served as controls. Ebstein's anomaly showed prolongation of the
delta value to 65 msec or greater in eight out of ten patients. Patients
with transposition of the great vessels showed a striking difference
from the preceding groups in that an average negative delta value was
obtained. Twenty-two patients of group 4 (RBBB) had delta values
within the norinal range.
This study has shown that a delta value greater than 65 msec is
suggestive of Ebstein's anomaly. In addition, if the delta value is
negative, transposition of the great vessels can be suspected.
IN THE NORMAL HEART mitral valve closure precedes
that of the tricuspid valve. These valves may be subjected to
unusual hemodynamics in certain forms of congenital heart
disease (such as transposition of the great arteries) or may
be structurally abnormal (as in Ebstein's anomaly of the
tricuspid valve). Since their precise point of closure can be
recorded echocardiographically, this study was undertaken
to evaluate the diagnostic significance of abnormal atrioventricular valve closure time.
The following groups of patients were assessed:
Group 1. 1) Normals - 40 patients (3 days - 20 years of
age); 2) Secundum atrial septal defect (ASD) - 10 patients
(1 month - 17 years of age); 3) Mitral valve prolapse syndrome or Barlow's syndrome (with mild mitral insufficiency) - 13 patients (8 - 17 years of age); 4) Pulmonary
hypertension - 12 patients (2 months - 21 years); 5)
Pulmonic stenosis - 6 patients.
Group 2: Ebstein's anomaly - 10 patients (1 day - 20
years of age).
Group 3: Transposition of the great vessels - 15 patients
(4 days - 17 years of age). Patients with associated defects
before or after any form of surgery were included.
Group 4: Complete right bundle branch block (RBBB) 25 patients (4 - 14 years of age).
All patients with RBBB had a QRS duration equal to or
greater than 110 msec. Fifteen with RBBB were examined
ultrasonically. In six instances of surgically induced RBBB,
echocardiograms were obtained pre and postoperatively.
Three of the patients had naturally occurring RBBB, the
etiology of which was unknown. Very few simultaneous
phonocardiograms and echocardiograms could be obtained
because the area required by the transducer and microphone
frequently were the same. Therefore, phonocardiographic
analysis of the major components of the first heart sound
(Ml-Tl) was performed in an additional ten patients with
surgically induced RBBB.
Material and Methods
Echocardiograms were obtained from the tricuspid and
mitral valves with a Hoffrel 101 ultrasonoscope. Either a
nonfocused 5 MHz ¼h inch or a focused 2.25 MHz ½/2 inch
transducer was used depending upon the age of the patient
and the ease of recording the structure sought. The echoes
were recorded at 75 or 125 mm/sec with 40 msec time lines.
In only two instances was a paper speed of 50 mm/sec used.
When possible, a simultaneous external phonocardiogram,
using a Cambridge type 72352 amplifier and type 53616
microphone, was obtained and recorded at a frequency and
position that would best display components of the first
heart sound. It was often difficult to record simultaneous
phonocardiograms in younger patients since the microphone placement interfered with transducer position.
All echocardiograms were obtained in the recumbent
position with the patient breathing normally. The transducer
was angled so that both anterior and posterior portions of
the valve could be seen and their point of coaptation identified, which thus defined closure (fig. 1).
Delta Value (A)
The term delta value was used to designate the difference
(in msec) between mitral closure (Mc) and tricuspid closure
(Tc) as determined by echocardiography. This was determined as follows:
The time taken from the Q wave of the ECG to tricuspid
closure and from Q to mitral closure was measured to the
nearest 5 msec (fig. 1). Three complexes with similar
preceding R-R intervals were measured for each value and
From the Department of Pediatrics, College of Medicine, University of
Cincinnati, Children's Hospital, Cincinnati, Ohio.
Supported by NIH Grant 5 TOI HL05728 and the American Heart
Association, Southwestern Ohio Chapter.
Address for reprints: Richard A. Meyer, M.D., Division of Cardiology,
Children's Hospital Medical Center, Cincinnati, Ohio 45229.
Received May 19, 1975; revision accepted for publication October 16,
1975.
513
514
CI RCULATION
VOL. 53, No. 3, MARCH 1976
EKG
EKG
TV
MV
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PHONO
I.z
FIGURE 1. Left) Mitral closure (Mc) occurs when the anterior and posterior mitral leaflets coapt. Right) Similarly, tricuspid closure (Tc) occurs at the point of coaptation. The delta value (Tc-Mc) is 25 msec.
the average taken for Q-Tc and Q-Mc. The difference
between Q-Tc and Q-Mc was then compared in the various
groups. The phase of respiration, per se, was not taken into
account although it was related to some extent by using
cycles with similar preceding R-R intervals.
Parkinson-White (WPW) syndrome (case 5: table 2). It was
possible to diagnose Ebstein's anomaly in an infant soon
after birth by echocardiography because of prolongation of
60 r
A
Results
50
*
Echocardiography
Group 1 Control Group (fig. 2)
The delta values of 40 normal subjects were plotted in
three age groups; 0-2 years, 2-10 years, and 10-20 years.
The mean value was 20 msec (SD =± 14) with a range from
-5 to 50 msec. The mean delta value was not age or rate
dependent although the lower values tended to be found in
younger infants.
Patients with right ventricular systolic hypertension (table
1) and Barlow's syndrome had values within this normal
range, as did cases with ASD, except for one patient with a
value of 60 msec. This group was considered normal and
served as the control group.
*0
-
Group 2 - Ebstein's Anomaly (table 2; fig. 3)
In eight of ten patients with this condition, the delta value
was 65 msec or greater. This value was higher than any other
group and was even seen in the presence of type B Wolff-
0
DO
40
0000*0
*o
30
Anm .. 0
30
-OAQ00
coo
*nb
(3
20
@00
*AA+
ec
e00
ee
l-z"
Do
000
Doo3
10 _leA.a
0
eNormal (N740)
mean = 20 msec.
(±S D -14)
-
gao
6
A.AS D (n 10)
mean = 25 msec.
OM.VPS (n 13)
meon 28 msec.
z
an
oPHT (Nzl2)
*A+
+
+PS (N 6)
-
+
S
-10
L- 0-2
___J
10-20
AGE (YEARS)
2-10
FIGURE 2. The delta values of the control group comprising
normals, secundum atrial septal defect (ASD), mitral valve prolapse
syndrome (M VPS), pulmonary hypertension (PHT) and pulmonic
stenosis (PS).
VALVE CLOSURE IN CONGENITAL HEART DISEASE/Milner et al.
515
TABTLE 1. Summoary of Echographic and Pressure Data in PatieCnts with RV Sylstolic Hypertcnsion
Patient
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
Age (yr)
3
1 4/12
14
8
Ii1
14
1 10/12
iI
21
6/12
3 9/1.2
2 8/12
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17.
2/12
6/12
18.
60
60
80
45
40
60
70
65
75
70
85
20
65
75
VSI)
VSI)
Pl)A
VSI1)
V81)
ASI)
VS1)
VS1-)
10/12
5 9/12
15 4/12
(msec)
PS
PS
Ps
PS
PS
PS
7/12
15.
16.
(.ITc
Dx
DO(RV
A
qMe
(msec)
(Te-Me)
(msec)
35
45
80
25
15
0
10Q3/6
40
40
.5
0
5
130/5
25
.15
41/4
70/5
30/7
20/10
41/14
50
60
75
10
50
60
25
76/9
137/6
110/0
105/5
[0/5
55
45
50
PA,
RV,
(mrm hfg)
(mm Hg)
31/6
87/9
20/12
19/
22/13
140/-2
12/6
40/4
10
0
10(
15
15
70/23
70/42
137/68
No record
95/25)
90/35
70
VSI)
Truncus I
45
45
45
0
1.5
70/5
100/8
80/38
32
ventrictilar septal defect; PHT
Group 3 - Transposition of the Great Vessels (fig. 4; table 3)
These patients were strikingly different from previous
groups. The average delta value for this group was -9 msec,
which denoted earlier closure of the tricuspid valve (situated
in the systemic ventricle) than the mitral valve. In 11/23
recordings the delta value was within the low normal range,
and 6/15 patients had a normal delta value at some state
during their course. Negative values seemed to occur
irrespective of age or associated lesions. This finding, too,
did not seem to be influenced by Mustard's operation. No
patient in this group had tricuspid insufficiency following the
Mustard repair.
Group 4 - Right Bundle Branch Block (figs. 5 & 6)
The delta values in patients with RBBB were within normal limits except for three patients who had values of 55, 60
and 65 msec. The six patients who had echocardiograms
1
2
3
4
5
6
7
8
9
Dclta Values (A) in Ebstein's Anoneady
Commnent
QPc-QQMc (msec)
80
Partial IRBBB
65
RtBBB, proloniged P-R
110
1BBB
80
IIBBB
75
W.P.W., Type B
Mild disease
55
70
55
Mild disease
90
70
10
Average
RBBB
Inifant, died
75
Abbreviations: RISBII
=
Parkinson-White syndlrome.
right bundle branch block; W.P.X.
=
Wolff-
EEisennienger by previous
cath; data not available
Underwent/ PA banding
=
tricuispid closure; VSJ)
the delta value (case 10), and this diagnosis was subsequently confirmed by autopsy. The two patients who had
values of 55 msec had mild disease by clinical estimation.
Case
[)own's synd1orome, PIIT by
clinical exam
92/53
=
D)own's syndrome
70
60
92/5
=
ItBBB
105
40
10
right ventricle; qTe
Ml, IJV dysfunction
Aorta 91/40
4'5
5-3
35
50
=
TABILI: 2.
17
8
15
13
75
60
60
Comrnents
15
VS/1)
Abbreviations: ASI) atrial sel)tal defecfl DOJV doiil)e otutlet right ventricle; LV left ventricle; M I
artery pressture; I'S
ptilinonary stenosis; PA = puilmonary artery; PA), patent dmiettus arteriostus; qoIM
block; ISV
MPA\,
(mm Hg)
initral insthfecieney; AlPA - mean pulmonary
= initral closuire; Il5.1- = right bundlle branch
puilmonary hypertension.
before and after open heart operation with right ventriculotomy had prolongation of the delta value postoperatively as compared to preoperatively. Nevertheless,
there was no increase in these values above normal.
1Phonocardiography
In every case where it was possible to record a
simultaneous phonocardiogram with the echocardiogram,
Mc preceded the initial high frequency components of the
first heart sound (Ml). Similarly, in instances where it was
clear, Tc preceded TI (the second group of high frequency
components of the first heart sound). However, the delta
value by echocardiography and the Ml-TI duration, in
YH
EBSTEINS
Q-T =135 mSec.
Q- M =60 mSec.
G- 75mSec.
FIGURE 3. Simultaneous tricuspid and mitral valve echoes in
Ebstein's anomaly. The delta value is 75 msec in the presence of a
normal P-R interval and QRS duration. Mc= mitral closure;
Tc= tricuspid closure.
5 16
CIRCULATION
p *
-1%,
~
VOL. 53, No. 3, MARCH 1976
p
raA TV--10
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ineraX
er te aelye riusidvlv cosr (c)pecde mralwavecosre
q T0 7OmSec.
c) hnc,th4dl0
q-mMcs8mSec.
ale a
F IGU RF 4. Tricusp id ( TV) and m it ral (M V) val ve ec h oes in a p a tien t with transpos itio n of th e grea t vessels. Th e R-R
intervals were the same, yet tricuspid valve closure (Tc) preceded mitral valve closure (Mc), hence, the delta value was
.-10 msec.
every instance, were the same, thus showing a definite correlation of the major components of the first heart sound to
valve closure. Analysis of the phonocardiograms of ten
patients with RBBB showed that there was some prolongation of MI to TI duration compared to preoperative
values (table 4).
Discussion
Controversy over the genesis of the first heart sound still
exists.1 Recent work has shown a definite correlation
T VTLE 3. Delta Values (msec) in Patients with 7Transposition
of the Great Arteries
Mtustard operation
Post
Case
pre
1
2
-10
-20
3
4
0
10
5
2}0
Later
Commnent
Coaretation
-20
-20
0
6
7
8
9
10
I11
12
13
-25
10(
10
15
-10
-3)0
10
15
-5
14
- :30
15
5
-15
PS (Blalock)
-5,0
PfIT
ASD, VSD
-5
PI-IT
Average -9.2 msec
= atrial sep)tal (lefect; IPT1
= pulmonary hyperpul nonary stenosis; VSD
ventricuilar septal defect.
Abbreviations: ASD
tension; I'S
=
between echocardiographic, phonocardiographic, cineangiographic and hemodynamic closure of the atrioventricular
valves.2 I While recognizing that there are many methods to
determine the precise timing of valve closure, we have taken
echocardiographic closure of the valves to represent actual
closure. Although delayed tricuspid closure has been
demonstrated previously in Ebstein's anomaly,6 8 the role of
RBBB has not been assessed extensively.
All our patients with complete RBBB had delta values less
than 65 msec and, with the exception of three, had values
less than 50 msec (fig. 7). The nature of the delay in these
three patients (55, 60 and 65 msec) is unclear; two of them
were examined postoperatively but not preoperatively and
may have had delayed delta values prior to surgery. The
etiology of the high delta value in the patient with naturally
occurring RBBB was also not apparent. The other two
patients with naturally occurring RBBB had normal delta
values. Furthermore, the five patients who had echocardiograms before and after their surgically induced RBBB had
delta values less than 50 msec. Therefore, it would appear
that RBBB has little effect on closure of the tricuspid valve
and plays a minor role, if any, in the large delta value recorded in Ebstein's anomaly.
Late closure of the tricuspid valve in Ebstein's anomaly
has been ascribed to the large leaflets which somehow cause
a mechanical delay in closure of the valve. Type B WPW9
does not influence the delay in Tc (table 2). As noted in our
mild cases, the delta value may be in the high normal range.
Thus, patients with Ebstein's anomaly may have normal
delta values. Nevertheless, a delta value longer than 65 msec
is strongly suggestive of the condition, since no other situation produced similar large delta values.
t4-cHbM~ e
VALVE CLOSURE IN CONGENITAL HEART DISEASE/Milner
E
4
.
t )
et
al.
517
I 1
~..
TV
Mt2ccpr, ;
.
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Q-T =125
j45 mSec
Q-Mc 80
FIGURE 5. Tricuspid (TV) and mitral (MV) valve echoes from a patient with surgically induced right bundle branch
block. The QRS duration is 120 msec, but the delta value is only 45 msec. Mc = mitral closure; Tc = tricuspid closure.
Rosenquist et al.12 recently described a spectrum of mitral
valve disease in 71% of 163 specimens with transposition of
the great vessels. Only 38 cases (23%) had entirely normal
mitral valves. The abnormalities included normally formed
valves with small mitral annuli (6%), normal valves and
restricted free margins of the anterior leaflets (33%) and
mitral valve anomalies (38%). The mitral valve anomalies
included: 1) underdevelopment of space between papillary
muscles; 2) underdevelopment of space between papillary
muscles and ventricular wall; and 3) indentation of anterior
leaflet and attachment to the ventricular septum. Three of
these specimens were similar to those described by Layman
and Edwards'0 and looked like Ebstein's anomaly. Thus, it
would seem reasonable to speculate that the delayed closure
of the mitral valve (resulting in negative delta values) may be
related to an anatomically abnormal mitral valve. On the
other hand, normal delta values would also be expected since
a large percentage of these patients have normal mitral
valves.
Of great interest was the finding of predominantly
negative delta values in patients with transposition of the
great arteries. Only one other patient (a normal infant in the
control group) had a negative delta value (fig. 7). One
hypothesis to explain this finding may be that the mitral
valve anomalies found in pathologic specimens with com-
plete transposition
of the
great
vessels"
12
in
some manner
affect the timing of closure of the valve. Layman and
Edwards10 found anomalies of the mitral valve in 13 of 88
specimens (I15%) which consisted of: l) cleft anterior leaflet;
2) partial persistent atrioventricularis communis; 3)
"6parachute" mitral valve; 4) abnormal adherence of the
anterior leaflet to the ventricular septum; and 5) "filigree"
of the mitral valve. Elliott et al.1" described an abnormality
of the mitral valve in only one of 60 cases. However, in that
specimen the basal aspect of the medial portion of each
mitral cusp was attached to the ventricular wall in a manner
similar to that observed in cases of Ebstein's malformation
of the tricuspid valve.
TAIBLE 4. Phonocardiogramrs of Patients with RBBIB Following Right Ventriculotomy
1Preop
Case
1
2
3
4
5
6
7
8
9
10
Diagnosis
VSJ) + PS
TOF
TOF + Waterston
TOF
TOF + Waterston
TOF
TOE
TOF
TOF
VSI)
iI I-Ti
(msec)
(mnsec)
30
45
35
30
50
40
60
65
50
55
100
75
QRS
Postop
l11
95
90
80
80
100
70
k2-P'2
(msec)
Il-TI
(msec)
(msec)
55
60
45
45
45
55
40
45
40
35
45
130
120
110
130
150
110
110
115
170
115
60
40
35
40
75
100
100
35
70
106
30
60
35
piu1monary stenosis5; QRS QRS (luration.; TOF
Abbreviations: HR
heart rate; IPS
septal defect; RIBBB= right bundle branch block.
=
QRS
HR'
85
80
110
80
110
115
110
112
80
96
A2-1P2
(msec)
70
80
50
90
75
60
40
35
70
65
tetralogy of Fallot; VSD -ventricular
CIRCULATION
518
VOL. 53, No. 3, MARCH 1976
8Cr
70F
60h
120 r
R.B.B.B.
* T.O.F.
o VS.D.
O OTHER
E
105F
0
0
90 K
50F
A
q Tcq Mc
40F
75
30F
+
A~
+
AL~
60K*-
20h
11)
q)
(t)
10
.j
Z.izr-
0
IZ)PRE-OP
Ave. ORS dur.=71msec.
POST-OP
NO OP
15
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0
++
++
0@0
_
I_
- mm
-
FIGURE 6. The delta values in patients with surgically induced
right bundle branch block (RBBB) did not exceed the normal value
(60 msec). One unoperated patient with RBBB had an unexplained
value of 65 msec. Dur = duration; Mc = mitral closure; Tc = tricuspid closure; T. 0. F. = Tetralogy of Fallot; V.S. D. = ventricular
septal defect.
1. Luisada AA, MacCanon DM, Kumar S, Feigen LP: Changing views on
the mechanism of the first and second heart sounds. Am Heart J 88: 503,
1974
2. Lanaido S, Yellin EL, Miller H, Frater RWM: Temporal relations of the
first heart sound to closure of the mitral valve. Circulation 47: 1006, 1973
3. Pohost GM, Dinsmore RE, Rubenstein JJ, O'Keefe DD, Grantham RN,
Scully HE, Beierholm EA, Frederiksen JW, Weisfelot ML, Daggett
30
14.
Ave. QRS dur. =l18msec.
Another hypothesis is that the negative delta value in
patients with transposition of the great vessels is related to a
change in compliance of the ventricles. Since the resistance
circuits to which the ventricles are exposed have been
reversed (i.e., right ventricle is systemic, left ventricle is
pulmonic), the compliance of the chambers is altered in such
a way that the closure of the atrioventricular valves result in
a negative delta value. Against this hypothesis are the
positive delta values found in all our patients with systolic
hypertension of the right ventricle (fig. 7). However, those
patients are not identical to transposition patients because
their left ventricles remain systemic.
At this time, the mechanism of the negative delta value
found in patients with transposition of the great vessels is
still obscure. Nevertheless, a negative delta value supports
the diagnosis of transposition. In addition, delta values
greater than 65 msec strongly suggest Ebstein's anomaly of
the tricuspid valve, since no other defect had a greater value.
Hopefully, greater experience with echocardiographic determination of atrioventricular valve closures should not only
provide insight into the etiology of abnormal delta values,
but also provide a reliable means by which to investigate the
relationship of atrioventricular valve closure to various
hemodynamic states in disease as well as in the normal
heart.
References
45 _ ...
-
1
++
++
0
0
emum- - --------+_
CC0
-I5
- - -
CO
OD
0
n
0
0
GO
-30
-- 45L
_
CONTROL PRE
POST
RBBB EBSTEINS
TGV
FIGURE 7. The delta values of the four groups of patients are
compared. The patients with transposition of the great vessels
(TG V) are striking because their values are predominantly negative
whereas the patients with right bundle branch block (RBBB) are
normal and those with Ebstein's anomaly are the only values greater
than 65 msec. Pre = preoperative; post = postoperative.
4.
5.
6.
7.
8.
9.
10.
11.
12.
WM: The echocardiogram of the anterior leaflet of the mitral valve:
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Layman TE, Edwards JE: Anomalies of the cardiac valves associated
with complete transposition of the great vessels. Am J Cardiol 19: 247,
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S Milner, R A Meyer, A W Venables, J Korfhagen and S Kaplan
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Circulation. 1976;53:513-518
doi: 10.1161/01.CIR.53.3.513
Circulation is published by the American Heart Association, 7272 Greenville Avenue, Dallas, TX 75231
Copyright © 1976 American Heart Association, Inc. All rights reserved.
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