Clinical-Echocardiographic Correlation of Myocardial Infarction with Extension to Right Chambers

Clinical-Echocardiographic Correlation of Myocardial Infarction with Extension to Right Chambers JESUS VARGAS-BARRON, M.D., NILDA ESPINOLA-ZAVALETA, M.D., ANGEL ROMERO-ChDENAS, M.D., SILVINO SIMON-RUIZ, M.D., CANDACE KEIRNS, M.D., MARC0 PENA-DUQUE, M.D., MARIA RIJLAARSDAM, M.D., and EULO LUPI-HERRERA, M.D. Department of Echocardiography, Instituto Nacional de Cardiologia “Ignacio Chavez,” Tlalpan, Mexico

I n order to determine the transesophageal echocardiographic characteristics in patients with acute myocardial infarction of right ventricle and establish the relationship between these findings, the clinical condition, and their prognostic value, 38patients consecutively admitted to the Instituto Na- cional de Cardiologia with a diagnosis of acute left ventricular myocardial infarction with extension to right ventricle and lor atrium were retrospectively studied. Of the left ventricular infarctions, 37 were posteroinferior and one anterior. Significant elevations of CPK and DHL were found in 35. I n 30 patients (78%) electrocardiographic evidence of extension of infarction to the right ventricle was found, and in 3, evidence of right atrial infarction. Twenty-one patients presented clinical data compatible with right ventricular infarction. I n 19, cardiac rhythm and atrioventricular conduction disturbances were documented. Coronary angiograms practiced on 34 patients demonstrated single- vessel (right coronary) disease in 12, affection of two vessels i n 14, and lesions in three or more in 6. Coronary arteries presented no significant lesions in two cases. With TEE, alterations of right ventricular segmental mobility were demonstrated in all patients, and in 6, alterations of right atrial mobility as well. As respects the ventricular wall movement index, 68.5% had total scores (RV + LV) of < 5. The other 31.5% had scores 2 5. I n 26%, the right ventricular wall movement index was 2 4. The RVDDILVDD ratio was 1 or less in 30 patients (78%) and > 1 in only 8 (22%). The conclusions from these findings are that: (1) TEE is an excellent diagnostic means of identifying right ventricular and lor atrial infarction; and (2) a relationship exists between the magnitude of right ventricular damage and a wall movement index of 5 or more or an RVILV diastolic diameter ratio > 1 postinfarction hemodynamic deterioration is significantly greater and the incidence of intrahospi- talary complications higher. (ECHOCARDIOGRAPHY, Volume 15, February 1998)

transesophageal echocardiography, myocardial infarction, enzymatic activity, functional class, right chambers

Over the last few years, interest in identifying right ventricular myocardial infarctions has grown, since these have been shown to be

frequently associated with left ventricular inferior infarction with an ample spectrum of clinical presentations. The repercussions of right ventricular damage may be minimal and masked by the manifestations of left ventricular infarction. However, in some cases right ventricular necrosis may be associated with atrioventricular conduction disturbances; it is not unusual for thrombi to form in right cavi-

Address for correspondence and reprints: Jesus Vargas- Barrbn, M.D., Department of Echocardiography, Instituto Nacional de Cardiologia “Ignacio Chavez,” Juan Badiano N ~ . 1, c0l. seccibn m - y a l p a n , 14080 ~ b ~ i ~ ~ , D.F., M ~ ~ - ico. Fax: 573-09-94.

Vol. 15, No. 2, 1998 ECHOCARDIOGRAPHY: A Jrnl. of CV Ultrasound & Allied Tech. 171

VARGAS-BARRON, ET AL.

172 ECHOCARDIOGRAPHY: A Jml. of CV Ultrasound & Allied Tech. Vol. 15, No. 2, 1998

ties, and right ventricular infarction can occa- sionally be responsible for cardiogenic shock.

From the point of view of noninvasive diagnosis, the ECG may show ST segment elevation of more than 1 mm in V4R. The sensitivity of this sign is 73% and the specificity

With radionuclide ventriculography, images of hemodynamically significant right ventricular infarction have been identified by the presence of abnormalities in wall movement with diminished ejection fraction. The sensitivity of these findings is 92% and the specificity 82%.2

When two-dimensional (2-D) echocardiography was limited to parasternal, apical, and subcostal images, the diagnostic criteria for right ventricular infarction were based on dilatation of the cavity and wall akinesis with abnormal movement of the interventricular septum because of the inversion of the pressure Doming of the interatrial septum toward the left atrium was correlated with the appearance of arterial hypotension, atrioventricular block, and increased mortality. More recent studies have demonstrated that 2- D echocardiographic findings that aid in estab- lishing the hemodynamic significance of right ventricular infarction are the percentage of col- lapse of the inferior vena cava during inspira- tion as well as quantification of the descent of the base of the right ~en t r i c l e .~

Today, transesophageal echocardiography (TEE) has become a technique of great value for identifylng the extension of a left ventricular infarction into the right ventricle and atrium?’ It provides more information than is available from transthoracic echocardiography (TTE) and is particularly useful for locating intracav- itary thrombi and abnormalities of atrial and ventricular segmental wall movement.

The purpose of this article is to describe the findings obtained from TEE in patients with acute right ventricular myocardial infarction, define the relationship between these findings and the clinical state of the patient, and establish their prognostic value.

Materials and Methods

The study included 38 patients who were admitted to the Coronary Care Unit of the Insti-

tuto Nacional de Cardiologia “Ignacio Chavez” between January 1990 and May 1995. Their clinical follow-up after release from the hospital varied from 6-60 months. A diagnosis of left ventricular myocardial infarction with extension to right ventricle and/or atrium was established in all. In 37, the location of the infarction was posteroinferior and in the other anterior.

The diagnosis of myocardial infarction was established on the basis of a history of chest pain, Q waves, and an ST elevation of at least one mm in different derivations of the ECG, in- cluding V4R and dorsal derivations. The diagnosis of atrial infarction was based on the exis- tence of PR segment abnormalities or the appearance of a negative deflection at the beginning of the P wave. Another finding used as a criterion for acute myocardial infarction was elevation of serum enzymes CPK and DHL. The group of patients included 35 men and 3 women with an average age of 56 years (range 38-75 years).

The variables evaluated in all patients included clinical data related to right atrial infarction, rhythm and atrioventricular conduction disturbances, and location and degree of obstruction of coronary arteries. Cardiac catheter- ization with coronary angiogram was performed in 34 patients between the second and thir- teenth day &r infarction. Coronary obstruction of 75% or more was considered significant.

Echocardiographic Study

TEES were performed between the seventh and twelfth day after infarctions. Two ma- chines were used; in 31 cases, it was a Siemens Sonoline CF with color-coded Doppler and a 5- MHz biplanar transducer. The subsequent seven studies were practiced with a Hewlett- Packard machine with a multiplanar transducer. Studies were carried out in the Coro- nary Care Unit with continuous monitoring of heart rate and blood pressure. A surface ECG was recorded during the echocardiographic study. Patients were lightly sedated with mi- dazolam for the procedure, which had an ap- proximate duration of 15 minutes.

Because of the limitations of biplanar TEE

CLINICAL-ECHOCARDIOGRAPHIC CORRELATION OF MYOCARDIAL INFARCTION

in visualizing the right ventricular apex and because this was a retrospective study, only transverse plane transgastric images at the level of papillary muscles (Fig. 1) and four- chamber transesophageal images were used for the general analysis of wall movement of both ventricles. With these recordings, left ventricular posteroinferior, anterior, and lateral walls and septum, and right ventricular inferior, lateral, and anterior walls were evaluated. Only in the seven cases performed with the multiplanar transducer was it possible to evaluate basal, middle, and apical thirds of right ventricular inferior and anterior walls in the transgastric long-axis image. However, for scoring alterations in wall movement (Wall Movement Index = WMI) only transgastric images at the level of papillary muscles and transesophageal four-chamber images were considered. Recordings were also obtained at the level of the atria in transverse and longitudinal planes; with simultaneous projection of 2-D images and pulsed wave Doppler spectra, the flow curves through the tricuspid and mitral valves were analyzed.

Alterations in wall movement supported right or left ventricular infarction. Depending on the amplitude of systolic movement, scores were given to the different walls. Normal wall movement was given a score of 0; hypokinesis

or diminished systolic wall thickening was scored as +l; akinesis or absence of systolic wall thickening as +2; dyskinesis or paradoxi- cal systolic movement as +3; and hyperkinesis or compensatory systolic movement of a wall without infarction as -1.

Another variable examined in both ventricles was end-diastolic diameter, which was measured using transverse plane recordings of four chambers at the level of the atrioventricular annulus. The relationship between the diastolic diameters of the ventricles was calcu- lated (RVDDaVDD).

Echocardiographic findings supporting right atrial infarction included akinesis of the atrial wall, thrombosis at the site of akinesis, dilatation of the atrial cavity with spontaneous contrast, and absence of atrial contribution to right ventricular filling in the presence of left atrial contraction.

The echocardiographic studies were analyzed separately by two expert cardiologist- echocardiographers who were unaware of the clinical, electrocardiographic, and hemodynamic data of the patients. The conclusions were reached by consensus.

Statistical Analysis

Statistical analysis of the relationship of right ventricular wall movement index, total

L

Figure 1. Diagram of transgastric image at the level of the papillary muscles showing the right Ventricular wall. A = anterior; I = inferior; L = lateral.

Vol. 15, No. 2,1998 ECHOCARDIOGRAPHY: A Jml. of CV Ultrasound & Allied Tech. 173


wall movement index, and the ratio of the diastolic diameters of the ventricles to NYHA functional class was performed using Student’s t- and Mann-Whitney U tests. The level of significance was P I 0.05.

Results

Clinical Findings

In 21 cases (55%) clinical data compatible with right ventricular infarction were present. These included arterial hypotension, right gal- lop rhythm, jugular plethora, and bradycar- dia. In all cases important enzymatic elevation was documented, CPK had values from 300 mg% to 3785 mg% (mean 2042 mg%), and DHL was increased to 170 mg% to 1762 mg% (mean 966 mg%).

The enzymatic activity in the remaining patients was the following: 14 had CPK between 55 mg% and 1687 mg% (mean 871 mg%) and DHL between 121 mg% and 1088 mg% (mean 604 mg%). Enzymatic activity was not deter- mined in three patients because they were hos- pitalized on the fifth and eighth day after infarction (Table I).

Electrocardiographic Signs

All of the patients had ECG evidence of left ventricular infarction. In 37 cases, the location of the infarction was posteroinferior and was associated with Q waves with a duration of > 0.04 seconds and elevation of the ST segment of 1 mm or more in leads DII, DIII, and aW. In only one case, the location was anterior with Q waves and elevation of the ST segment in leads

Of the 38 patients, in 30 (78%) ECG evidence of extension of the infarction to right ventricle characterized by elevation of the ST segment of 1 mm or more in leads V,R and V,R was found. In 3 cases, right atrial infarction was diag- nosed; 1 showed a negative deflection at the beginning of the P wave and the other 2 elevation of the PR segment (Table I).

In 19 of the 38 patients cardiac rhythm and atrioventricular conduction disturbances were documented. In 13 first- or second-degree atrioventricular blocks appeared; in 2 of these,

V,-V,.

right bundle branch blocks coexisted. In 3 patients, atrioventricular junction rhythm was identified; in 2, atrial fibrillation; and in 1, right bundle branch block. It was necessary to use pacemakers in 11 of the 16 patients with atrioventricular conduction disturbances, 9 provisional and 2 definitive.

Coronary Angiogram

The findings of the coronary angiograms practiced on 34 patients (89%) appear in Table 11. In two cases, no significant coronary obstructions were observed. In 12 patients, lesions in a single vessel were identified, corre- sponding to the right coronary artery. In 14 patients, lesions were found in two vessels; in 13 of them, obstructions existed in the right coronary and anterior descending branch, while in the other they were found in the right and circumflex coronary arteries. Lesions of three or more vessels were observed in six patients.

Obstruction of the right coronary artery was demonstrated in the 34 coronary angiograms performed. The right coronary lesion was in the proximal third in 19 patients, in the middle third in 10, and in the distal third in 3. Right atrial circulation was evaluated and was considered adequate because the atrial branches of the right coronary and/or circumflex artery were patent in 29 patients. In five cases, significant obstructions of atrial circulation were found. In two patients, atrial circulation had obstructions of 100%. Two patients only had one patent atrial branch from the circumflex artery and the other a very small branch from the right coronary artery.

Transesophageal Echocardiography

Alterations in left ventricular posteroinferior wall movement were found in 37 cases and in the anterior wall in 1. All of the patients (38) had extension to right ventricle with alterations of inferior wall movement in 26 cases, inferior and lateral wall movement in 8, inferior wall and septal movement in 1, inferior and lateral wall and septal movement in 1, and alterations of movement of all right ventricular walls (anterior, inferior, lateral, and septal) in 2 (Figs. 2 and 3).

174 ECHOCARDIOGRAPHY: A Jml. of CV Ultrasound & Allied Tech. Vol. 15, No. 2, 1998

TABLE

I

Cha

ract

eris

tics

of P

atie

nts

~ ~

Ele

ctro

card

iogr

am

Enz

ymes

T

rans

esop

hage

al E

choc

ardi

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phy

(mgO

/oo)

Func

tion

al

Loc

atio

n of

R

hyth

m a

nd A

V

RV

/LV

N

o.

Infa

rctio

n C

ondu

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n D

istu

rban

ces

Cp

mH

L

rati

o T

WM

I R

V-W

MI

RA

Ext

C

ompl

icat

ions

C

lass

1

2 3 4 5 6 7 8

9 10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

LV

PI

LV

PI+R

V

LV

PI + R

V

LV

PI+R

V

LV

PI + R

V +

RA

LV

PI+R

V

LV

PI+R

V

LV

PI+R

V

LV

PI+R

V

LV

PI

LW

I L

VPI

+RV

L

VPI

+RV

L

VPI

L

VPI

+RV

L

VPI

L

VPI

+RV

L

VPI

+RV

L

VPI

+ RV

+ RA

L

VPI

+R

V

LV

PI+R

V

LV

PI+R

V

LV

PI+R

V

LV

PI+R

V+R

A

LV

PI + R

V

LV

PI

LV

PI+R

V

LV

PI+R

V

LV

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LV

PI+R

V

LV

PI+R

V

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LV

PI +

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L

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LV

PI+R

V

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+ 1" &

2"

AV

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RB

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2" A

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lock

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& 2

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Atr

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Atr

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ibri

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2650

/539

13

05/2

49

1817

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97

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8 16

89/1

87

443/

524

2000

/479

20

00/3

90

1500

/899

37

85/1

265

662/

252

2636

/504

63

7/16

8 20

38/4

03

1080

/360

31

8/27

3 33

8717

35

2000

/529

60

0/28

9 17

56/2

53

3040

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25

38/1

762

-/- 55/1

70

7131

268

2311

205

544/

279

1687

/345

-/

- 20

4/12

1 11

52/3

44

1500

/321

30

0/28

2 -/

- 12

5813

87

1488

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8 11

61/3

96

330/

297

1.77

1.

10

1.13

1.

90

1.20

1.

21

0.66

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92

0.70

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88

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1.0

0.69

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0.91

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98

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0.92

0.

93

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1.77

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0.85

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74

0.92

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73

0.76

13

8 5

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= A

trio

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LV

= L

eft v

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B =

Pos

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= P

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roin

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or; R

A E

xt =

Rig

ht A

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BB

B =

Rig

ht B

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ranc

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lock

; RV

= R

ight

ven

tric

le; R

V-

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I =

Rig

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entr

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all M

ovem

ent I

ndex

; SE

C =

Spo

ntan

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Ech

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ast;

TWMI =

Tot

al W

all M

ovem

ent I

ndex

.


TABLE I1

Coronary Angiogram

Right Coronary Anterior Descending Circumflex Atrial Circulation

No. Segment ‘7c Obstruction L7C Obstruction 8 Obstruction % Obstruction

1 2 3 4 5 6 7 8 9

10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38

Proximal Proximal Vertical Proximal Proximal Proximal - -

-

Proximal Distal Vertical Vertical Vertical Vertical Distal Proximal Proximal Proximal Proximal Vertical Proximal Proximal

Proximal Vertical Proximal Proximal Proximal Proximal Proximal Vertical

-

- -

Vertical Vertical Distal Proximal

100 90 50

100 100 100

Not Performed 0

Not Performed 90 50 60 75 35

100 80 60 85

100 90

100 99

100 Not Performed

100 90

100 100 100 100 40 50 0

Not Performed 100 100 100 90

70 90 75

100 90

0 Not Performed

0 Not Performed

0 90 40

Diffuse 25 60 30 50

0 0 0

75 0 0

Not Performed 70 0

85 99 95

Diffuse 40 50 0

Not Performed 0 0 0 0

0 0 0 0 0 0

Not Performed 0

Not Performed 0

100 0

75 0 0 0 0

20 0 0 0 0 0

Not Performed 40 0

Diffuse 75 0

70 0 0 0

0 0 0 0

Not Performed

0 0 0

100 Small Circumflex Branch

100 Not Performed

0 Not Performed

0 0 0 0 0 0 0 0 0

0 0 0

Small Right Coronary Branch

Small Circumflex Branch Not Performed

0 0 0 0 0 0 0 0 0

0 0 0 0

Not Performed

As respects scoring of the severity of alterations in mobility of both ventricles (WMI), 26 patients (68.5%) were found to have total scores (RV + LV) of < 5 and the remaining 12 (31.5%) of 5 or more. The right ventricular WMI L 4 in 10 patients (26%). Included in these were the four patients who died in the hospital phase and two who are still alive in functional Class III/IV. Only four patients with

RV-WMI of 4 are in functional Class I. The remaining 28 patients (74%) had right ventricular WMI of < 4. The RVDDLVDD ratio obtained in the four-chamber transverse plane was 1 or less in 30 patients (78%) and > 1 in only 8 (22%).

In 6 patients, alterations in right atrial wall movement were documented, 2 with hypokinesis (Fig. 4) and 2 with akinesis. In four of these

176 ECHOCARDIOGRAPHY. A Jml. of CV Ultrasound & Allied Tech. Vol. 15, No. 2,1998


Figure 2. Four-chamber transesophageal recording in diastole in a patient with infarction of right cavities. Dilatation and generalized ventricular hypokinesis with akinesis of the atrial wall can be seen. There is doming of both interventricular and interatrial septa toward the left. LA = left atrium; LV = left ventricle; RA = right atrium; RV = right ventricle.

cases, spontaneous contrast was observed, and in only one patient a thrombus was found on the akinetic atrial wall (Fig. 5) . In the two patients with right atrial akinesis, pulsed wave Doppler showed the loss of atrial contribution to right ventricular filling (Fig. 6) in the presence of left atrial contraction (Fig. 7). In 31 patients (81.6%) tricuspid regurgitation, mild in 30 cases and severe in 1, was documented.

In 29 cases (76.3%), mitral regurgitation was demonstrated. It was mild in 27, moderate in 1, and of important hemodynamic repercussion in 1. The mitral insufficiency in the last two cases resulted from partial rupture of the pos- teromedial papillary muscle. These patients underwent coronary artery bypass grafts and implantation of mechanical prosthetic valves. In one patient, rupture of interventricular septum was evident; treatment consisted of coronary artery bypass graft and closure of the septal defect. However, the patient succumbed 19 days after surgery. In one case, a foramen ovale was found to be patent, and color Doppler demonstrated a right-to-left shunt. In seven patients, mild pericardial effusion was found. In two patients, left ventricular posterobasal aneurysms were evident (Table I).

Figure 3. Transesophageal four-chamber image in systole in a patient with right atrial and ventricular infarction. Abbreviations as before.

Clinical Evolution

The clinical follow-up of 31 patients varied from 6 to 60 months (average 33 months). Of these, 24 were in functional Class I, 5 in functional Class 11, 1 in functional Class 111, and 1 in functional Class III/IV. The last two patients are in global heart failure, and both have per- manent pacemakers because of atrioventricular conduction disturbances. In four cases, fol-

Figure 4. Transesophageal image with M-mode recording in a longitudinal plane at the basal level perpendicular to the interatrial septum. The right atrium is dilated, and spontaneous echo contrast can be observed as well as significantly diminished wall movement (arrows). Abbreviations as before.

Vol. 15, No. 2, 1998 ECHOCARDIOGRAPHY: A Jml. of CV Ultrasound & Allied Tech. 177


Figure 5. Transesophageal echocardiographic image in a transverse plane at the level of the atria. A thrombus can be seen adhering to the akinetic right atrial wall (arrows). Abbreviations as before.

low-up was < 1 month. Two of these patients died in cardiogenic shock and two during surgery, one for removal of an aneurysm and the other for closure of a ventricular septa1 rupture. Three patients were lost to follow-up; in these, functional class could not be established.

Statistical Analysis

Statistical analysis was performed on the findings from 35 patients. A significant differ-

Figure 6. Transesophageal recording with pulsed Doppler spectrum of tricuspid diastolic flow. There is no atrial contribution to right ventricular filling (arrows). Abbreviations as before.

Figure 7. Transesophageal four-chamber image in a patient with infarction of right cavities. Doppler analysis shows left atrial contraction (arrows). Ab- breviations as before.

ence with P = 0.057 for Student’s t-test and P I 0.03 for Mann-Whitney U test was found for NYHA Functional Class I/II and a total WMI of > 5; and NYHA Class I I W and a total WMI of 5 or more.

The association of NYHA Functional Class I/II and an RV-WMI of c 4; and Functional Class I I W and an RV-WMI of 4 or more showed significance with P = 0.005 for Student’s t-test and P 5 0.01 for the Mann-Whitney U test.

Statistical significance also existed for the relationship of Functional Class 141 and an RVDDLVDD ratio of one or less; and Func- tional Class I I W and an RVDDLVDD > one with P = 0.022 for Student’s t-test and P I 0.001 for the Mann-Whitney U test.

Discussion

In this group of patients with left ventricular infarction, extension of the necrosis to right ventricle was suspected on the basis of clinical findings in only 21 (55%). As respects elevation of enzymes, we found that all patients with hemodynamic consequences of right ventricular infarction had significantly increased levels of CPK and DHL. However, similar enzymatic elevations were observed in patients with small right ventricular infarctions.

The diagnosis of right ventricular infarction

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by electrocardiography was achieved in only 30 cases (78%), a value in agreement with that reported in the literature. Those cases without electrocardiographic diagnosis could probably be explained by the transient nature of the ST elevation. In one series, 48% of the patients had resolution of electrocardiographic changes within 10 hours of the onset of symptoms.8 Moreover, the ECG showed evidence of right atrial infarction in only 3 of the 6 patients in which TEE demonstrated dyssynergy of the atrial wall. This indicates that correct diagnosis requires a complete EGG with all of the right precordial leads as soon as possible.

It is noteworthy that half of the patients had rhythm or atrioventricular conduction disturbances, particularly atrioventricular block. This supports the high incidence of the finding reported in the l i t e r a t~ re .~ In our series, conduction disturbances occurred in 16 cases, or 42%. Of these, 13 were first- or second-degree atrioventricular blocks and in the other 3, complete blocks with junction rhythm. This high incidence of A-V block is not seen in patients with left ventricular posterior infarction without extension to right ventricle.

It was possible to evaluate the coronary angiogram in only 34 of the 38 patients. In two cases, no significant atherosclerotic lesions could be found, while in the remaining 32, important obstruction of the right coronary artery was seen. In 19 cases, there was coexistent obstruction of the anterior descending artery, and in 7 patients of the circumflex artery.

When the right coronary artery lesion was proximal (19 cases), the patients had torpid evolution with arterial hypotension, right gal- lop rhythm, and atrioventricular conduction disturbances in 53% of the cases (10 patients).

When the total wall movement index was 5 or more, the RV-WMI 4 or more, and the RVDD/ LVDD ratio > 1, patients were in a worse functional Class (III/IV).

TEE was the diagnostic technique that best demonstrated the extension of the infarction to right chambers. In all 38 patients, it showed alterations of right inferior wall movement and in some cases dyssynergy that extended to lateral, septal, and even anterior walls. It also made it possible to demonstrate the extension

of the ischemic process to the right atrium. Atrial wall hypokinesis was evident in four cases and akinesis in two. In four of these cases, spontaneous contrast could be identified in the atrial cavity, and in one a thrombus adhering to the akinetic wall. In the two patients with right atrial akinesis, the tricuspid flow “a” wave could not be detected, confirming the lack of atrial contraction. The hemodynamic deterioration associated with extension of ischemia to the right atrium may be important; 3 of the 6 patients with atrial dyssynergy in TEE were in functional Class III/IV.

When alterations of right atrial wall movement were compared to findings from coronary angiograms, patients with right atrial akinesis (2) proved to have total occlusion of the atrial circulation, while those with hypokinesis received some blood supply from a small atrial branch of the circumflex (2) or right coronary artery (1). In one patient with right atrial hypokinesis, a coronary angiogram was not performed.

In one patient, TEE showed sudden right-to- left shunting through a previously unsus- pected patent foramen ovale; as right ventricular function improved, the shunt diminished. This finding has been described in other re- p o r t ~ ~ ~ and may adversely affect the patient’s clinical course.

Color Doppler showed that regurgitation of atrioventricular valves is frequent. In 31 patients (81.6%) tricuspid insufficiency, mild or moderate in all but one, was documented. In 29 cases (76.3%) mitral insufficiency was identified, which was mild to moderate in 27. In the two cases with severe mitral regurgitation, TEE demonstrated partial rupture of the posterome- dial papillary muscle. TEE also confirmed the rupture of the interventricular septum in another patient. In all three, the transesophageal echocardiographic findings provided the surgical indications.

Finally, as respects prognosis, the results of our series are in agreement with published re- ports. Mortality during hospitalization was 10%; in other series it has been as high as 31%.“ This contrasts dramatically with myocardial infarction limited to the left ventricular posteroinferior wall, in which the mortality is e 6%.

Vol. 15, No. 2,1998 ECHOCARDIOGWHY: A Jrnl. of CV Ultrasound & Allied Tech. 179

VARGAS-BARRON, ET AL

Morbidity is also more important during hospitalization. In our series, rhythm and atrioventricular conduction disturbances were frequent, and in 11 of 16 patients with A-V conduction disturbances, it was necessary to use pacemakers. Fortunately, in nine the require- ment was transitory. In only two were perma- nent pacemakers implanted.

On the basis of the results the following conclusions were reached.

TEE is an excellent diagnostic technique for identifying myocardial infarction of the right ventricular inferior wall as well as its extension to other walls. Likewise, TEE can docu- ment the extension of ischemia to the right atrium. A relationship exists between the magnitude of right ventricular damage and variables available from transesophageal recordings. A total WMI of 5 or more and a RV-WMI of 4 or more, or a ratio of RVLV diastolic diameters of > 1 are associated with greater hemodynamic deterioration after ventricular infarction and a higher incidence of intrahospi- talary complications. I n these patients, short- or intermediate-term cardiac function will be more affected.

Extension of the ischemic process to right atrium is associated with greater intrahospital- ary morbidity.

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Clinical-Echocardiographic Correlation of Myocardial Infarction with Extension to Right Chambers