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Electrocardiographic and vectorcardiographic changes following surgery in persistent common atrioventricular canal
Electrocardiographic Changes
Following
Common LEONARD
and Vectorcardiographic Surgery
Atrioventricular
in Persistent Canal*
STEINFELD, M.D., ARTHIUR GRISHMAN, M.D., F.A.C.C. and EPHRAIM DONOSO, M.D. New York, New
D
EFECTS of the lower atria1 septum, whether isolated or associated with abnormalities of the atrioventricular valves and ventricular septum, are generally classified as defects of Endocardial or the atrioventricular canal. atrioventricular cushion defects are alternative designations. A wide variety of anatomic lesions are generally regarded as true defects of the atrioventricular canal because some embryologic maldevelopment of the endocardial cushions is common to all.1-3 Current classification of defects of the A-V canal, however, does not include a group of congenital intracardiac lesions which from a clinical standpoint mimic the true lesions and in certain instances appear to have similar embryologic origin.d Congenital aberrations of the mitral and tricuspid Lralves, mitral or tricuspid abnormalities associated with atria1 defects (ostium secundum) and combined atria1 and ventricular septal defects are some of the lesions in reference.5 It is apparent, therefore, that our present understanding of A-V cushion defects is still somewhat fragmentary, and as a result, classification and nomenclature are unsatisfactory. E:or practical purposes, it seems most convenimt at the present time ta adopt a classification which subdivides A-V cushion defects The into complete and incomplete types.4 complete type is characterized by a large crescentic defect in the lower atria1 septum which overlies cleft mitral and tricuspid valves and a defective superior rim of the ventricular septum. The incomplete form of A-V cushion defect includes a variety of lesions in the region of the atrioventricular canal at or above the level of the -4-V.’ valves.
York
Before the elucidation of the characteristic electrocardiographic and vectorcardiographic patterns observed in atrioventricular cushion defects, the clinical diagnosis was frequently confused with atria1 defects of the secundum type, ventricular defects, combined atria1 and ventricular defects and occasionally with rheumatic heart disease. The difficulty arises because the pulmonary and apical systolic murmurs and thrills, the widely split second sound, the enlarged heart and prominent pulmonaryvasculature are clinical features peculiar not only to defects in the region of the atrioventricular canal but also to other intracardiac anomalies associated with left-to-right shunt, or mitral valvular disease with pulmonary congestion. The electrocardiagramG and vectorcardiogram ,7 however, are quite distinct in atrioventricular cushion defects and may ultimately prove to be the most useful tools Except for distinguishing this type of anomaly. for a rare report to the contrary, the electrocardiogram and vectorcardiogram are diagnostic The electrofrom early infancy to adulthood. is characterized by either left cardiogram axis deviation or a concordant S wave in the standard leads and an rS pattern in aVF. The right-sided precordial leads often show an RSR’ pattern, but a variety of other patterns has been observed in proved cases of atriovenFirst degree heart tricular cushion defects. block is a common finding.“,7 While the 12 lead electrocardiogram dcmonstrates a narrow range of variation, the vectorcardiogram assumes a remarkable degree of The vectorcardiographic picture constancy’ demonstrates a superior orientation of the main
* From the Division of Cardiology, Departments of Pediatrics and Medicine, The Mount Sinai Hospital. New York New York. NOVEMBER
1962
643
644
Steinfeld, .VR
(Irishman
and 1)onoso
aVF
““I
FIG. I (hsc 1. r:lcct~“ca~tlir,graIns. /‘,i~/w~~/~i~i. l’irst tlc,qr.w Ilrart block. right atria1 cnlarqrmmt \vith prominent first prak, left axis drviation and rsK ’ in lrad V ,. Po.c/~j~rn~i~c. Notiw shortening of P-K interval. ‘l’hr second prak of the P wavr is now tallrr than thr first. ‘I‘herv is diminrltion of the 1’ and QKS voltage. and rsK’ is no lonqcr prrsent in Icad VI.
FIG. 2. (:asr 1, Vcctorcardiograrns. A-co~~rnlirr~. ‘1‘11~.(>KS loop in the frontal (I:) and sagitt,rl (S) plants is superiorly orirntcad with the terminal sc-,qmrnt mow slowly inscribed. Pos/o,brm~iuc. ‘There: is no chanzc in the inscription of the QRS loop, hlct the loop is more horizontally oricntcd. ‘The terminal QRS apprndagc is much shortrr and orwntc4 mainly postrriorly and superiorly. hotly- of the QRS planes, the
with
QRS
loop
loop
cardiographic
in the l”ronta1 and sagittal
counterclockwise in
the
and
frontal
inscription plane.
vectorcardiographic
of
Elcctroanaly-
in addition. may assist in the clinical evaluation of the completeness or incompleteness of a surgical repair. The following three cases exemplify their use. sis not
only
aid
in
(EASE
diagnosis
hut,
REPORTS
1. J. B., a white female, was regarded as normal until age 2 when respiratory difficulty appeared as the earliest manifestation of congestive heart failure. Administration of digitalis and diuretics produced rapid improvement as long as they were continued. Withholding digitalis for periods in CASE
CKI’SS of twx) weeks resultrd in a reapparance of cxcrtional dyspnea and fdtigability. Cardiac evaluation at another hospital led to a diagnosis of Lutembacher’s s~.ndromr. PhFsicul examination at age 14 revealed a precordial chest prominence and heaving impulses over the pulmonic and apical regions. On auscultation, therr was a grade 3 apical blowing systolic murmur. The second sound at the base was loud and widely split and was followed by a soft diastolic murmur along the left sternal border. The remainder of the physical rsamination was not remarkable. Roentgenographic examination revealed an enlarged heart with prominent pulmonary vascular markings. ‘I’he right atria1 contour and the main pulmonary artery were conspicuous. The electrocardiogram disclosed first degree heart block. The P waves were THE
AMERICAN
JOURNAL
OF CARDIOLOGY
Common
Atrioventricular
B
,A F1o. 3. (:asr 2. angiocartiioqram.
* By I)r. K. E. Gross, Children’s 1962
c
C, retrograde Icft ventricular I\, preoperative rocntgenogram. B, postoperative roentgrnogram. Mitral insufficiency results in visualization of the Note contrast material filling the left ventricle.
notched with the first peak taller than the second. ‘I’here was left axis deviation and an rSR’ complex in lead 1.1 (Fig. 1). 7’hr WCtorcardiogram showed a superior orientation The direction of in the sagittal and frontal planes. inscription in the horizontal and frontal planes was counterclockwise. There was a slow terminal appendagc oriented anteriorly and to the right (Fig. 2). Curdinl. catheterization performed on December 30. 1955. demonstrated a left-to-right atria1 shunt with mild elevation of the pulmonary artery pressure The clinical impression from the (35 5 mm. Hg). foregoing data was ostium primum defect with a cleft mitral valve. The clinical diagnosis was conand a complete repair was firm<-d at operation, accomplished in 1960. * Postoperntive Results: One month after operation no Fluoroscopically. significant murmurs were heard. the heart appeared smaller and less active. The electrocardioyrum presented a number of changes (Fig. 1). The P-R interval was shorter, the P waves were smaller and the second peak was taller than the first. Grnthrall), there was a diminution in QRS voltage. Left axis deviation persisted, but the preoperative rSR ’ \vas no longer apparent. The S waves in leads 1. a\X and \‘,; either disappeared or diminished in depth. ‘l’he amplitude of the R wave in aVR was reduced. and a small g wave appeared in leads Vj and V,;. ‘1%~ ‘1’ 12;avc voltage decreased in the precordial leads. The po.stopwative vectorcardiogram (Fig. 2) demonstrated no change in the direction of inscription in the horizontal and frontal planes. In the sagittal and frontal planes, the QRS loop moved from the superior orientation, seen preoperatively, toward the zero axis. ‘l’he terminal appendage became smaller and assutned a posterior and superior orientation.
NOVtMBER
645
Canal
Hospital,
Boston.
Comrnmf: The electrocardiographic and vectorcardiographic patterns observed in the postoperative period were almost within normal limits. This suggested that surgical correction was responsible for the almost complete normalization of the electrocardiogram and vectorcardiogram. Improved conduction in conjunction with diminished heart size, absence of significant murmurs, and normal exercise tolerance argues strongly in favor of complete correction. In contrast to Case 1, the following case is an example of a patient with proved incomplete repair of an ostium primum defect with a cleft mitral valve. In this instance also, postoperative electrical events did not portray the relatively normal characteristics previously descriljed. CASE 2. B. R., a negro female, was considered a normal infant until 3 months of age when a heart murmur was noted. She remained asymptomatic until age 9 when fatigability was noted. There was no history of decompensation, cyanosis, syncope or squatting. Physical examination at age 12 revealed a grade 3, harsh systolic ejection murmur in the second left intercostal space associated with a thrill. Tht. second sound at the base was loud and widely split and succeeded by a short, early, blowing diastolic murmur. The edge of the liver was palpable two centimeters below the costal margin. The remainder of the physical examination was unremarkable. Roentgenographic examination (Fig. 3A) shelved the heart slightly enlarged in its transverse diameter. The main pulmonary artery was prominent, and the pulmonary vascular markings were increased. The
646
FIG. 4. Case 2. TO/I,the prcoperativc Postoperative serial electrocardiograms
Steinfeld,
Irishman
and Donoso
electrocardiogram shows an SI, Sz, Ss and rS pattern in the precordial Icads. show smaller S WBVPSin lcad I and taller K waves in thr left precordial Icads.
e/e&ocardiogran~ (Fig. 4) showed left axis deviation of the P waves and a concordant S wave in standard leads I, II and III. A clR configuration was seen in lead aVR. In leads V, to \:a therr was an rS pattern. and in CrGa deep S wave. 7%e vectorcnrdio,qram(Fig. 5) was oriented superiorly and anteriorly. ‘l‘he direction of inscription in the horizontal plane >vas clockwise. Cardiac cathrferization performed on hlarch 25. 1957, demonstrated a large left-to-right atria1 shunt. ‘[‘he pressure in the right ventricle was mildly clrvated (45 7 mm. Hg). The rlirrictrl impression was ostium primum defect with a cleft mitral valve. At operation, a large inferiorly placed atria1 septal defect was repaired. No abnormality of the atrioventricular valves was observed at surgery. Early in the postoperative period, signs of decompensation that appeared rcsponded to digitalis. Except for the persistence of harsh systolic and mid-diastolic murmurs, the remainder of the postoperative course was not unusual. Postoperative Results: One year after surgery, the heart was clinically and roentgenographically (Fig. 3B) larger than before operation. A harsh systolic murmur was audible along the lower left sternal
bordrr, and a short, rough, mid-diastolic murmur \vas present in the third intercostal space. Cardiac rathetcrization and dye dilution studies failed to dcmonstrate a left-to-right shunt. Retrograde left venrriculography, however, clearly revealed the presence of mitral insufficiency (Fig. 3C). Several postoperative electrocardiograms [Fig. 3) shvwed progressive diminution in depth of the S \
AMERICAN
JOURNAL
OF
CARDIOLOGY
Common
FIG. 5. Case 2. The preoperative vectorcardiogram Thr diwction of inscription in the horizontal plane a constant counterclockwise inscription of the QRS
Atrioventricular
CASE -3. G. T,, a Puerto Rican male, was well until age 9 when a heart murmur and enlarged heart A year later rheumatic were noted for the first time. heart disease was diagnosed, penicillin prophylaxis was instituted, and he was placed in a convalescent home for eight months. There was no preceding history- of ,joint pains, fever or exercise limitation. Physical examination at age 14 revealed an enlarged heart. ‘There was a grade 2 blowing, apical systolic murmur. ‘l‘he second sound at the base was widely A soft mid-diastolic split and of normal intensity. murmur was heard inside the apex. Routtgrnographir examination (Fig. 6A) showed the heart enlarged and the apex displaced downward and laterally-. The main pulmonary artery was prominent, and the pulmonary vascular markings were increased. 1962
647
was oriented mainly superiorly (F and S) and antuiorly (H). is clockwise. Serial postoperative vectorcardiograms demonstrate loop in the horizontal planr and an orientation to the left.
reflected in the electrocardiogram and vector-. cardiogram by a disappearance of the pattern of right ventricular hypertrophy. The residual mitral deformity accounted for the graphic evidence of progressive left ventricular enlargeThe postoperative roentgenograms corment. rotrorated the electrocardiographic evidence of progressive left ventricular enlargement. The following third case is another example of a11 incompletely repaired atrioventricular In this instance, as in the precushion defect. ceding one, the postoperative electrocardiogram and \,ectorcardiogram failed to develop any degree of norrnali;lation.
NO\‘F,MREK
Canal
7.h~ electrocardiogram (Fig. 7) showed enlarged P waves, first degree heart block, marked left axis deviation and an rSr’ in lead Vi. The T waves were The orctorcardiotall and peaked in leads VS and Vf. gram in the horizontal plane was oriented mainly posteriorly and to the left, with a slow right anterior The direction of inscription of terminal appendage. the QRS loop in the horizontal plane was counterIn the sagittal and frontal planes the clockwise. QRS loop was entirely superior. ‘I’he direction of inscription in the frontal plane was counterclockwise. Cardiac catheterization performed on October 15, 1958, revealed a left-to-right shunt at the ventricular level and mild pulmonary hypertension. The catheter was observed passing from the right atrium directly The clinical diagnosis was into the left ventricle. ostium primum defect with cleft mitral valve. ‘I‘he clinical impression was confirmed at operation. A large atria1 defect was closed with the aid of an Ivalons’ prosthesis, and a cleft mitral leaflet was repaired with interrupted silk sutures. The postoperative course was not unusual. Postoperative Results: In comparison to the preoperative electrocardiogram, the early postoperative electrocardiogram (Fig. 7) showed P waves in lead II had lower voltage and became negative in leads V1 to V4. Left axis deviation persisted, but the duration of the QRS in the right-sided precordial leads increased to 0.11 second, and the R’ became much taller. There was increased depth to the T waves in leads V, and V2 and inversion of the T waves in \‘a to Vg. Ten months later, the QRS narrowed and the R’ in V-1 diminished. The left precordial ‘I‘ waves became
indicates first drqrcr .A-\’ block, lrft axis deviation and a QRS of FIG. 7. Preoperative electrocardiogram (lo,;1 7/S) rlcctrocardiogram (l/18/60) &picts lower voltage of the P wave and widening 1%’configuration in VI. Postoprrativc eight months later (O/2/60) shows narrowof the QRS complex with an rsR ’ complex in VT. The electrocardiogram ing of the QRS complex and incrcasc of voltage of the R wave in the left precordial lcads. positive and dcvelopcd a tall peaked configuration. The early postoperatioe octorc.ardiopams showed the QRS loop in the horizontal plane was less posteriorly oriented, but the direction of inscription ‘The terminal appendage was more was unchanged. anteriorly oriented and revealed a slowrr rate ol In other planes the QRS loop remained inscription. unchanged except for a slower inscription of the terminal segment. Ten months later, the QRS loop was However, practically unchanged in the three planes.
there was a Paster inscription of the terminal segment. I%)ostoperntiaP roc-xtgenograms (Fig. 6B) demonstrated a significant increase in heart size as compared with In addithe appearance of the heart preoperatively. tion, there was a residual grade 2, long, harsh murmur at the apex, followed by a mid-diastolic flow murmur. Although postoperative studies have not been performed to date, cardiographic and clinical analyses suggest an incomplete repair with residual mitral insufficiency. THE
AMERICAN
JOURNAL
OF CARDIOLOGY
Common
Atrioventricular
DISCUSSION Despite the aggregate of tests and instrumentation available for the investigation of cardiac abnormalities, the electrocardiogram and vectorcardiogram continue to be the most accurate guides to diagnosis of defects of the atrioventricular canal. Characteristic is the superior orientation and counterclockwise inscription of the vectorcardiographic loop in the frontal plant. The pattern seen on the electrocardiogram: although more variable, is represented b)- left asis deviation or a concordant S wave in leads I, II and III, in conjunction with an rS complex in lead aVF. The number of exceptions to this are few. Of 18 proved cases previousi\. published,7 14 had left axis deviation and 4 clcmonstrated a concordant S pattern in the standard leads; 11 of the 18 cases showed an RSR’ pattern in lead VI; the remaining 7 casts had an rR ‘, Rs, rS, qR or QS pattern in the right precordial leads. Electrocardiographic vectorcardioand graphic observations following surgical correction of atrioventricular cushion defects have Case 1 of this not been reported previously. report demonstrates “normalization” of the path\va)- of conduction after total correction of an ostium primum defect and a cleft mitral valve, which suggests that the genesis of the basic electrocardiographic abnormality, at least in this case, \vas not due to a congenital aberration of the left bundle branch system.” Instead, the left axis deviation and superior orientation may ha\.e been related in part to enlargement of the chamber, which, after correction, resulted in a change in the electrical forces of the heart. In Case 1 the postoperative electrocardiogram continued to show left axis deviation, but there were smaller P waves, a normal P-R interval, diminished QRS voltage in the frontal plane, a disappearance of the RSR’ complex in VI and taller R waves in the left precordial leads. Tht~r findings probably indicate changes in hemod>.namics and a concomitant reduction in heart size incident to anatomic correction of ;II~ intracardiac abnormality. This feature of the postoperative electrocardiogram suggests its possible value in appraising the postoperative result of surgery. In Case 1 complete repair resulted in changes toward “normalization” of the electrocardiogram and vectorcardiogram, while Cases 2 and 3 illustrated instances of
NO\‘E&!BER 1962
Canal
649
incomplete repair with corresponding a bnormalities depicted on the cardiographic tracings. Observations on a larger number of cases with adequate anatomic control should assist in the evaluation of the electrocardioqram and vectorcardiogram for this purpose. SUMMARY The electrocardiogram and vectorcardiogram are probably the most reliable tools in the diagnosis of atrioventricular cushion defects. Our observations require further evaluation. Evidence has been offered suggesting that the electrocardiogram and vectorcardiogram also may assist in the evaluation of the effectiveness of surgical repair. It appears that there is enough evidence to conclude that the electrocardiographic and vectorcardiographic patterns observed in atrioventricular cushion defects are due not only to a congenital aberration of the left bundle but also to cardiac enlarrgement. ACKNOWLEDGMENT We
wish to express our appreciation to Dr. #Sigmund Brahms for permission to publish the angiocardiogram, to Dr. Alvin J. Gordon for use of the catheterization data, and to Miss Ruth .Jaspan for her rontinued cooperation.
REFERENCES 1. ROGERS, H. M. and EDWARDS, J. R. Incomplete division of the atrioventricular canal with patent interatrial foramen primum (persistent common atrioventricular ostium): report of five cases and review of the literature. Am. Heart J., 36: 28, 1948. 2. CAMPBELL, M. and MISSEN, G. A. K. Endocardial cushion defects. &it. Heart J., 19: 403, 1957. 3. WAKAI, C. S. and EDWARDS: J. 15. Pathologic study of persistent common atrioventricular canal. Am. Heart J., 56: 779, 1958. 4. BURCHELL, J. B., DUSHANE, J. W. and BRAXDENBURG, R. 0. The electrocardiogram of patients with atrioventricular cushion defects (defects of the atriovcntricular canal). Am. J. Cardio[., 6: 574. 1960. 5. ESPINO-VELA, J., PORTILLO, B., RUEION, V. and ARANDE, S. Combined auricular and ventricular septal defects; a study of five casrs with postmortem confirmation in three. Am. Hmrt J., 56: 856, 1958. 6. TOSCANO-BARBOZA, E.. BRANDENBURG, R. 0. and BURCWELL, H. B. Electrocardiographic studies of cases with intracardiac malformations of the atrioventricular canal. Pm. &zff .Wwt. Mayo Clin., 31: 513. 1951. 7. BEREGOVICH, J., BLUFFER, S., DONOSO, E. and GRISHMAN, A. The vectorcardiogram and electrocardiogram in persistent common atrioventricular canal, Circulation,21 : 63, 1960.
Following
Common LEONARD
and Vectorcardiographic Surgery
Atrioventricular
in Persistent Canal*
STEINFELD, M.D., ARTHIUR GRISHMAN, M.D., F.A.C.C. and EPHRAIM DONOSO, M.D. New York, New
D
EFECTS of the lower atria1 septum, whether isolated or associated with abnormalities of the atrioventricular valves and ventricular septum, are generally classified as defects of Endocardial or the atrioventricular canal. atrioventricular cushion defects are alternative designations. A wide variety of anatomic lesions are generally regarded as true defects of the atrioventricular canal because some embryologic maldevelopment of the endocardial cushions is common to all.1-3 Current classification of defects of the A-V canal, however, does not include a group of congenital intracardiac lesions which from a clinical standpoint mimic the true lesions and in certain instances appear to have similar embryologic origin.d Congenital aberrations of the mitral and tricuspid Lralves, mitral or tricuspid abnormalities associated with atria1 defects (ostium secundum) and combined atria1 and ventricular septal defects are some of the lesions in reference.5 It is apparent, therefore, that our present understanding of A-V cushion defects is still somewhat fragmentary, and as a result, classification and nomenclature are unsatisfactory. E:or practical purposes, it seems most convenimt at the present time ta adopt a classification which subdivides A-V cushion defects The into complete and incomplete types.4 complete type is characterized by a large crescentic defect in the lower atria1 septum which overlies cleft mitral and tricuspid valves and a defective superior rim of the ventricular septum. The incomplete form of A-V cushion defect includes a variety of lesions in the region of the atrioventricular canal at or above the level of the -4-V.’ valves.
York
Before the elucidation of the characteristic electrocardiographic and vectorcardiographic patterns observed in atrioventricular cushion defects, the clinical diagnosis was frequently confused with atria1 defects of the secundum type, ventricular defects, combined atria1 and ventricular defects and occasionally with rheumatic heart disease. The difficulty arises because the pulmonary and apical systolic murmurs and thrills, the widely split second sound, the enlarged heart and prominent pulmonaryvasculature are clinical features peculiar not only to defects in the region of the atrioventricular canal but also to other intracardiac anomalies associated with left-to-right shunt, or mitral valvular disease with pulmonary congestion. The electrocardiagramG and vectorcardiogram ,7 however, are quite distinct in atrioventricular cushion defects and may ultimately prove to be the most useful tools Except for distinguishing this type of anomaly. for a rare report to the contrary, the electrocardiogram and vectorcardiogram are diagnostic The electrofrom early infancy to adulthood. is characterized by either left cardiogram axis deviation or a concordant S wave in the standard leads and an rS pattern in aVF. The right-sided precordial leads often show an RSR’ pattern, but a variety of other patterns has been observed in proved cases of atriovenFirst degree heart tricular cushion defects. block is a common finding.“,7 While the 12 lead electrocardiogram dcmonstrates a narrow range of variation, the vectorcardiogram assumes a remarkable degree of The vectorcardiographic picture constancy’ demonstrates a superior orientation of the main
* From the Division of Cardiology, Departments of Pediatrics and Medicine, The Mount Sinai Hospital. New York New York. NOVEMBER
1962
643
644
Steinfeld, .VR
(Irishman
and 1)onoso
aVF
““I
FIG. I (hsc 1. r:lcct~“ca~tlir,graIns. /‘,i~/w~~/~i~i. l’irst tlc,qr.w Ilrart block. right atria1 cnlarqrmmt \vith prominent first prak, left axis drviation and rsK ’ in lrad V ,. Po.c/~j~rn~i~c. Notiw shortening of P-K interval. ‘l’hr second prak of the P wavr is now tallrr than thr first. ‘I‘herv is diminrltion of the 1’ and QKS voltage. and rsK’ is no lonqcr prrsent in Icad VI.
FIG. 2. (:asr 1, Vcctorcardiograrns. A-co~~rnlirr~. ‘1‘11~.(>KS loop in the frontal (I:) and sagitt,rl (S) plants is superiorly orirntcad with the terminal sc-,qmrnt mow slowly inscribed. Pos/o,brm~iuc. ‘There: is no chanzc in the inscription of the QRS loop, hlct the loop is more horizontally oricntcd. ‘The terminal QRS apprndagc is much shortrr and orwntc4 mainly postrriorly and superiorly. hotly- of the QRS planes, the
with
QRS
loop
loop
cardiographic
in the l”ronta1 and sagittal
counterclockwise in
the
and
frontal
inscription plane.
vectorcardiographic
of
Elcctroanaly-
in addition. may assist in the clinical evaluation of the completeness or incompleteness of a surgical repair. The following three cases exemplify their use. sis not
only
aid
in
(EASE
diagnosis
hut,
REPORTS
1. J. B., a white female, was regarded as normal until age 2 when respiratory difficulty appeared as the earliest manifestation of congestive heart failure. Administration of digitalis and diuretics produced rapid improvement as long as they were continued. Withholding digitalis for periods in CASE
CKI’SS of twx) weeks resultrd in a reapparance of cxcrtional dyspnea and fdtigability. Cardiac evaluation at another hospital led to a diagnosis of Lutembacher’s s~.ndromr. PhFsicul examination at age 14 revealed a precordial chest prominence and heaving impulses over the pulmonic and apical regions. On auscultation, therr was a grade 3 apical blowing systolic murmur. The second sound at the base was loud and widely split and was followed by a soft diastolic murmur along the left sternal border. The remainder of the physical rsamination was not remarkable. Roentgenographic examination revealed an enlarged heart with prominent pulmonary vascular markings. ‘I’he right atria1 contour and the main pulmonary artery were conspicuous. The electrocardiogram disclosed first degree heart block. The P waves were THE
AMERICAN
JOURNAL
OF CARDIOLOGY
Common
Atrioventricular
B
,A F1o. 3. (:asr 2. angiocartiioqram.
* By I)r. K. E. Gross, Children’s 1962
c
C, retrograde Icft ventricular I\, preoperative rocntgenogram. B, postoperative roentgrnogram. Mitral insufficiency results in visualization of the Note contrast material filling the left ventricle.
notched with the first peak taller than the second. ‘I’here was left axis deviation and an rSR’ complex in lead 1.1 (Fig. 1). 7’hr WCtorcardiogram showed a superior orientation The direction of in the sagittal and frontal planes. inscription in the horizontal and frontal planes was counterclockwise. There was a slow terminal appendagc oriented anteriorly and to the right (Fig. 2). Curdinl. catheterization performed on December 30. 1955. demonstrated a left-to-right atria1 shunt with mild elevation of the pulmonary artery pressure The clinical impression from the (35 5 mm. Hg). foregoing data was ostium primum defect with a cleft mitral valve. The clinical diagnosis was conand a complete repair was firm<-d at operation, accomplished in 1960. * Postoperntive Results: One month after operation no Fluoroscopically. significant murmurs were heard. the heart appeared smaller and less active. The electrocardioyrum presented a number of changes (Fig. 1). The P-R interval was shorter, the P waves were smaller and the second peak was taller than the first. Grnthrall), there was a diminution in QRS voltage. Left axis deviation persisted, but the preoperative rSR ’ \vas no longer apparent. The S waves in leads 1. a\X and \‘,; either disappeared or diminished in depth. ‘l’he amplitude of the R wave in aVR was reduced. and a small g wave appeared in leads Vj and V,;. ‘1%~ ‘1’ 12;avc voltage decreased in the precordial leads. The po.stopwative vectorcardiogram (Fig. 2) demonstrated no change in the direction of inscription in the horizontal and frontal planes. In the sagittal and frontal planes, the QRS loop moved from the superior orientation, seen preoperatively, toward the zero axis. ‘l’he terminal appendage became smaller and assutned a posterior and superior orientation.
NOVtMBER
645
Canal
Hospital,
Boston.
Comrnmf: The electrocardiographic and vectorcardiographic patterns observed in the postoperative period were almost within normal limits. This suggested that surgical correction was responsible for the almost complete normalization of the electrocardiogram and vectorcardiogram. Improved conduction in conjunction with diminished heart size, absence of significant murmurs, and normal exercise tolerance argues strongly in favor of complete correction. In contrast to Case 1, the following case is an example of a patient with proved incomplete repair of an ostium primum defect with a cleft mitral valve. In this instance also, postoperative electrical events did not portray the relatively normal characteristics previously descriljed. CASE 2. B. R., a negro female, was considered a normal infant until 3 months of age when a heart murmur was noted. She remained asymptomatic until age 9 when fatigability was noted. There was no history of decompensation, cyanosis, syncope or squatting. Physical examination at age 12 revealed a grade 3, harsh systolic ejection murmur in the second left intercostal space associated with a thrill. Tht. second sound at the base was loud and widely split and succeeded by a short, early, blowing diastolic murmur. The edge of the liver was palpable two centimeters below the costal margin. The remainder of the physical examination was unremarkable. Roentgenographic examination (Fig. 3A) shelved the heart slightly enlarged in its transverse diameter. The main pulmonary artery was prominent, and the pulmonary vascular markings were increased. The
646
FIG. 4. Case 2. TO/I,the prcoperativc Postoperative serial electrocardiograms
Steinfeld,
Irishman
and Donoso
electrocardiogram shows an SI, Sz, Ss and rS pattern in the precordial Icads. show smaller S WBVPSin lcad I and taller K waves in thr left precordial Icads.
e/e&ocardiogran~ (Fig. 4) showed left axis deviation of the P waves and a concordant S wave in standard leads I, II and III. A clR configuration was seen in lead aVR. In leads V, to \:a therr was an rS pattern. and in CrGa deep S wave. 7%e vectorcnrdio,qram(Fig. 5) was oriented superiorly and anteriorly. ‘l‘he direction of inscription in the horizontal plane >vas clockwise. Cardiac cathrferization performed on hlarch 25. 1957, demonstrated a large left-to-right atria1 shunt. ‘[‘he pressure in the right ventricle was mildly clrvated (45 7 mm. Hg). The rlirrictrl impression was ostium primum defect with a cleft mitral valve. At operation, a large inferiorly placed atria1 septal defect was repaired. No abnormality of the atrioventricular valves was observed at surgery. Early in the postoperative period, signs of decompensation that appeared rcsponded to digitalis. Except for the persistence of harsh systolic and mid-diastolic murmurs, the remainder of the postoperative course was not unusual. Postoperative Results: One year after surgery, the heart was clinically and roentgenographically (Fig. 3B) larger than before operation. A harsh systolic murmur was audible along the lower left sternal
bordrr, and a short, rough, mid-diastolic murmur \vas present in the third intercostal space. Cardiac rathetcrization and dye dilution studies failed to dcmonstrate a left-to-right shunt. Retrograde left venrriculography, however, clearly revealed the presence of mitral insufficiency (Fig. 3C). Several postoperative electrocardiograms [Fig. 3) shvwed progressive diminution in depth of the S \
AMERICAN
JOURNAL
OF
CARDIOLOGY
Common
FIG. 5. Case 2. The preoperative vectorcardiogram Thr diwction of inscription in the horizontal plane a constant counterclockwise inscription of the QRS
Atrioventricular
CASE -3. G. T,, a Puerto Rican male, was well until age 9 when a heart murmur and enlarged heart A year later rheumatic were noted for the first time. heart disease was diagnosed, penicillin prophylaxis was instituted, and he was placed in a convalescent home for eight months. There was no preceding history- of ,joint pains, fever or exercise limitation. Physical examination at age 14 revealed an enlarged heart. ‘There was a grade 2 blowing, apical systolic murmur. ‘l‘he second sound at the base was widely A soft mid-diastolic split and of normal intensity. murmur was heard inside the apex. Routtgrnographir examination (Fig. 6A) showed the heart enlarged and the apex displaced downward and laterally-. The main pulmonary artery was prominent, and the pulmonary vascular markings were increased. 1962
647
was oriented mainly superiorly (F and S) and antuiorly (H). is clockwise. Serial postoperative vectorcardiograms demonstrate loop in the horizontal planr and an orientation to the left.
reflected in the electrocardiogram and vector-. cardiogram by a disappearance of the pattern of right ventricular hypertrophy. The residual mitral deformity accounted for the graphic evidence of progressive left ventricular enlargeThe postoperative roentgenograms corment. rotrorated the electrocardiographic evidence of progressive left ventricular enlargement. The following third case is another example of a11 incompletely repaired atrioventricular In this instance, as in the precushion defect. ceding one, the postoperative electrocardiogram and \,ectorcardiogram failed to develop any degree of norrnali;lation.
NO\‘F,MREK
Canal
7.h~ electrocardiogram (Fig. 7) showed enlarged P waves, first degree heart block, marked left axis deviation and an rSr’ in lead Vi. The T waves were The orctorcardiotall and peaked in leads VS and Vf. gram in the horizontal plane was oriented mainly posteriorly and to the left, with a slow right anterior The direction of inscription of terminal appendage. the QRS loop in the horizontal plane was counterIn the sagittal and frontal planes the clockwise. QRS loop was entirely superior. ‘I’he direction of inscription in the frontal plane was counterclockwise. Cardiac catheterization performed on October 15, 1958, revealed a left-to-right shunt at the ventricular level and mild pulmonary hypertension. The catheter was observed passing from the right atrium directly The clinical diagnosis was into the left ventricle. ostium primum defect with cleft mitral valve. ‘I‘he clinical impression was confirmed at operation. A large atria1 defect was closed with the aid of an Ivalons’ prosthesis, and a cleft mitral leaflet was repaired with interrupted silk sutures. The postoperative course was not unusual. Postoperative Results: In comparison to the preoperative electrocardiogram, the early postoperative electrocardiogram (Fig. 7) showed P waves in lead II had lower voltage and became negative in leads V1 to V4. Left axis deviation persisted, but the duration of the QRS in the right-sided precordial leads increased to 0.11 second, and the R’ became much taller. There was increased depth to the T waves in leads V, and V2 and inversion of the T waves in \‘a to Vg. Ten months later, the QRS narrowed and the R’ in V-1 diminished. The left precordial ‘I‘ waves became
indicates first drqrcr .A-\’ block, lrft axis deviation and a QRS of FIG. 7. Preoperative electrocardiogram (lo,;1 7/S) rlcctrocardiogram (l/18/60) &picts lower voltage of the P wave and widening 1%’configuration in VI. Postoprrativc eight months later (O/2/60) shows narrowof the QRS complex with an rsR ’ complex in VT. The electrocardiogram ing of the QRS complex and incrcasc of voltage of the R wave in the left precordial lcads. positive and dcvelopcd a tall peaked configuration. The early postoperatioe octorc.ardiopams showed the QRS loop in the horizontal plane was less posteriorly oriented, but the direction of inscription ‘The terminal appendage was more was unchanged. anteriorly oriented and revealed a slowrr rate ol In other planes the QRS loop remained inscription. unchanged except for a slower inscription of the terminal segment. Ten months later, the QRS loop was However, practically unchanged in the three planes.
there was a Paster inscription of the terminal segment. I%)ostoperntiaP roc-xtgenograms (Fig. 6B) demonstrated a significant increase in heart size as compared with In addithe appearance of the heart preoperatively. tion, there was a residual grade 2, long, harsh murmur at the apex, followed by a mid-diastolic flow murmur. Although postoperative studies have not been performed to date, cardiographic and clinical analyses suggest an incomplete repair with residual mitral insufficiency. THE
AMERICAN
JOURNAL
OF CARDIOLOGY
Common
Atrioventricular
DISCUSSION Despite the aggregate of tests and instrumentation available for the investigation of cardiac abnormalities, the electrocardiogram and vectorcardiogram continue to be the most accurate guides to diagnosis of defects of the atrioventricular canal. Characteristic is the superior orientation and counterclockwise inscription of the vectorcardiographic loop in the frontal plant. The pattern seen on the electrocardiogram: although more variable, is represented b)- left asis deviation or a concordant S wave in leads I, II and III, in conjunction with an rS complex in lead aVF. The number of exceptions to this are few. Of 18 proved cases previousi\. published,7 14 had left axis deviation and 4 clcmonstrated a concordant S pattern in the standard leads; 11 of the 18 cases showed an RSR’ pattern in lead VI; the remaining 7 casts had an rR ‘, Rs, rS, qR or QS pattern in the right precordial leads. Electrocardiographic vectorcardioand graphic observations following surgical correction of atrioventricular cushion defects have Case 1 of this not been reported previously. report demonstrates “normalization” of the path\va)- of conduction after total correction of an ostium primum defect and a cleft mitral valve, which suggests that the genesis of the basic electrocardiographic abnormality, at least in this case, \vas not due to a congenital aberration of the left bundle branch system.” Instead, the left axis deviation and superior orientation may ha\.e been related in part to enlargement of the chamber, which, after correction, resulted in a change in the electrical forces of the heart. In Case 1 the postoperative electrocardiogram continued to show left axis deviation, but there were smaller P waves, a normal P-R interval, diminished QRS voltage in the frontal plane, a disappearance of the RSR’ complex in VI and taller R waves in the left precordial leads. Tht~r findings probably indicate changes in hemod>.namics and a concomitant reduction in heart size incident to anatomic correction of ;II~ intracardiac abnormality. This feature of the postoperative electrocardiogram suggests its possible value in appraising the postoperative result of surgery. In Case 1 complete repair resulted in changes toward “normalization” of the electrocardiogram and vectorcardiogram, while Cases 2 and 3 illustrated instances of
NO\‘E&!BER 1962
Canal
649
incomplete repair with corresponding a bnormalities depicted on the cardiographic tracings. Observations on a larger number of cases with adequate anatomic control should assist in the evaluation of the electrocardioqram and vectorcardiogram for this purpose. SUMMARY The electrocardiogram and vectorcardiogram are probably the most reliable tools in the diagnosis of atrioventricular cushion defects. Our observations require further evaluation. Evidence has been offered suggesting that the electrocardiogram and vectorcardiogram also may assist in the evaluation of the effectiveness of surgical repair. It appears that there is enough evidence to conclude that the electrocardiographic and vectorcardiographic patterns observed in atrioventricular cushion defects are due not only to a congenital aberration of the left bundle but also to cardiac enlarrgement. ACKNOWLEDGMENT We
wish to express our appreciation to Dr. #Sigmund Brahms for permission to publish the angiocardiogram, to Dr. Alvin J. Gordon for use of the catheterization data, and to Miss Ruth .Jaspan for her rontinued cooperation.
REFERENCES 1. ROGERS, H. M. and EDWARDS, J. R. Incomplete division of the atrioventricular canal with patent interatrial foramen primum (persistent common atrioventricular ostium): report of five cases and review of the literature. Am. Heart J., 36: 28, 1948. 2. CAMPBELL, M. and MISSEN, G. A. K. Endocardial cushion defects. &it. Heart J., 19: 403, 1957. 3. WAKAI, C. S. and EDWARDS: J. 15. Pathologic study of persistent common atrioventricular canal. Am. Heart J., 56: 779, 1958. 4. BURCHELL, J. B., DUSHANE, J. W. and BRAXDENBURG, R. 0. The electrocardiogram of patients with atrioventricular cushion defects (defects of the atriovcntricular canal). Am. J. Cardio[., 6: 574. 1960. 5. ESPINO-VELA, J., PORTILLO, B., RUEION, V. and ARANDE, S. Combined auricular and ventricular septal defects; a study of five casrs with postmortem confirmation in three. Am. Hmrt J., 56: 856, 1958. 6. TOSCANO-BARBOZA, E.. BRANDENBURG, R. 0. and BURCWELL, H. B. Electrocardiographic studies of cases with intracardiac malformations of the atrioventricular canal. Pm. &zff .Wwt. Mayo Clin., 31: 513. 1951. 7. BEREGOVICH, J., BLUFFER, S., DONOSO, E. and GRISHMAN, A. The vectorcardiogram and electrocardiogram in persistent common atrioventricular canal, Circulation,21 : 63, 1960.