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Page 1: Surgical treatment of congenital valvular aortic stenosis · Surgical treatment of congenital valvular aortic stenosis PATIENTS AND METHODS Between September 1967 and July 1975, 22

Thorax (1976), 31, 398.

Surgical treatment of congenital valvularaortic stenosis

LUIGI CHIARIELLO, PETER VLAD,and S. SUBRAMANIAN

Departments of Paediatric Cardiology and Cardiovascular Surgery, Children's Hospital,Buffalo, New York, USA

Chiarieflo, L., Vlad, P., and Subamanian, S. (1976). Thorax, 31, 398-404. Surgicaltreatment of congenital valvular aortic stenosis. Twenty-two patients with congenitalvalvular aortic stenosis were surgically treated between 1967 and July 1975. Five (23%)were under 1 year of age (group I) and 17 (77%) were between 2 and 24 years (group II).All infants exhibited severe congestive heart failure and electrocardiographic (ECG)evidence of left ventricular hypertrophy (LVH) with strain pattern. In group II, anginawas present in three cases, syncope and fatigue in two; the ECG indicated LVH in 10cases (59%) with strain pattern in five (29%). A bicuspid aortic valve was present in77% (17/22) of the cases; 32% had other cardiac anomalies. Aortic valvotomy wasperformed on cardiopulmonary bypass in 20 cases, and with deep hypothermia andcirculatory arrest in two.Three infants under 1 month of age with associated anomalies died (hospital mortality

14%). Intraoperative average peak left ventricular-aortic systolic pressure gradientdecreased from 86 to 21 mmHg (P<0 001). Late clinical (in all cases) and haemo-dynamic (26%) follow-up showed severe restenosis in two patients of group II; one ofthem had a second operation, the other one died three and a half years postoperatively.Results assessed on the basis of symptoms, ECG changes, aortic valve function, and/orhaemodynamic findings were fair in the two surviving infants. Results in group II wereexcellent in three, satisfactory in seven, fair in four, and poor in two cases. In infants,aortic valvotomy is a palliative procedure which carries a high risk. In the older agegroup, early and latc results are more gratifying.

Valvular aortic stenosis comprises approximately50% of all forms of congenital left ventricularoutflow tract obstruction reported in several largeseries (Morrow, Sharp, and Braunwald, 1958;Braunwald et al., 1963; Keith, Rowe, and Vlad,1967; Bertranou et al., 1971; Lambert et al., 1971).The malformation is usually discovered in the firstfive years of life. Auscultation discloses a systolicejection murmur, commonly maximal at the secondright interspace and frequently associated with anearly systolic click. When indicated by deteriorat-ing clinical and haemodynamic conditions, a com-missurotomy is performed for relief of the obstruc-tion. In the favourable cases of simple fusion ofrelatively normal cusps, surgical treatment wouldappear curative. However, in many instances, thevalve apparatus is grossly abnormal because of

rudimentary, thick, and deformed cusps. A com-missurotomy in these cases would result in a pallia-tive relief of obstruction, control of symptoms,and prevention of sudden death.

In infants, isolated valvular stenosis is rarelyseen. Usually it is associated with other congenitalcardiovascular defects. Symptomatic patients inthis age group have an operative risk that is dis-turbingly high, although lower than non-operativetreatment (Coran and Bernhard, 1969; Vlad et al.,1971; Bernhard et al., 1973).These problems indicate that surgical treatment

of valvular aortic stenosis still presents less thanoptimal results. In this report we present ourseries of patients, the concepts of management wehave followed, and the results obtained in a seven-year period at the Buffalo Children's Hospital.

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Page 2: Surgical treatment of congenital valvular aortic stenosis · Surgical treatment of congenital valvular aortic stenosis PATIENTS AND METHODS Between September 1967 and July 1975, 22

Surgical treatment of congenital valvular aortic stenosis

PATIENTS AND METHODS

Between September 1967 and July 1975, 22patients underwent intracardiac repair of valvularaortic stenosis at the Buffalo Children's Hospital.At operation five infants (23%) ranged in agefrom 2 days to 6 months (group I) and 17 (77%)from 2 years to 24 years (group II). Age distribu-tion is reported in Table I. In none of the caseswas there a previous history of rheumatic heartdisease. All but two patients underwent preopera-tive cardiac catheterization and selective angiocar-diography. Indications for haemodynamic studywere a history of heart failure, syncope or angina,and/or evidence of electrocardiographic (ECG)changes in patients with clinical findings consis-tent with aortic stenosis. Left ventricular hyper-trophy on ECG was evaluated according to themethod of Keith et al. (1967).

TABLE 1AGE DISTRIBUTION AND MORTALITY IN 22 PATIENTS

WITH VALVULAR AORTIC STENOSIS

No. of HospitalAge Patients Percent Deaths Percent

<3 mth 4 8 3 753 mth-6 mth 1 5 - -

2 yr-5 yr 2 9> 5 yr 15 68 - -

Total 22 100 3 14

Indications for surgery consisted of any of thesymptoms listed, even with normal electrocardio-graphic findings and irrespective of the catheter-ization data. Haemodynamic parameters onlywere used in the asymptomatic patients with nor-mal electrocardiograms. A left ventricular-aorticpeak systolic pressure gradient of 50 mmHg or

more was considered to be an indication for sur-

gery. We adopted the 50 mmHg pressure gradientas reported by Lambert et al. (1971) to separatemild from moderate aortic stenosis and 75 mmHgto separate moderate from severe stenosis. Aortic

regurgitation was considered haemodynamicallysignificant when the pulse pressure was over 60mmHg (Lambert et al., 1971). Follow-up data byclinical and/or haemodynamic assessment in our

cardiology department have been obtained in allcases from two months to seven years afteroperation (mean follow-up time 35 months). Lateresults were arbitrarily graded on the basis of thefollowing criteria:Excellent result-patient asymptomatic, normalelectrocardiogram, left ventricular-aortic peaksystolic pressure gradient equal to or less than25 mmHg, no aortic insufficiencySatisfactory result-patient asymptomatic, stableelectrocardiogram with no strain pattern, mild leftventricular-aortic pressure gradient (26-50 mmHg), mild aortic insufficiency (pulse pressure lessthan 60 mmHg)Fair result-patient slightly symptomatic (FC II,

NYHA classification), electrocardiogram stablewith or without strain pattern, moderate left ven-tricular-aortic pressure gradient (51-75 mmHg),significant aortic insufficiency (pulse pressureequal to or greater than 60 mmHg)Poor result-patient symptomatic (FC III-IV,NYHA classification), further operation necess-ary, impaired electrocardiogram with appearanceof a strain pattern, severe left ventricular-aorticpressure gradient (greater than 75 mmHg), signifi-cant aortic insufficiency (pulse pressure greaterthan 60 mmHg).

In evaluating the surgical results, each patientwas assigned to the poorest category in which hisclinical data could be located.

GROUP I Five infants were included in this group.Three were males and two females. They rangedin age from 2 days to 6 months, four being lessthan 3 months old (Table I). All the infants pre-sented with congestive heart failure and one ofthem was cyanotic (Table II).

Electrocardiograms indicated left ventricularhypertrophy with a strain pattern in all instances(Table III). Preoperative cardiac catheterization

TABLE IIPREOPERATIVE SYMPTOMS IN 22 PATIENTS WITH VALVULAR AORTIC STENOSIS

Symptomatic SymptomNo. of

Group Patients No. % Angina Syncope Fatigue Heart Failure Cyanosis

I 5 5 100 - - - 5 1II 17 7 41 3 2 2 - -Total 22 12 55 3 2 2 5 1

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L. Chiariello, P. Vlad, and S. Subramanian

TABLE IIIPREOPERATIVE AND POSTOPERATIVE ELECTROCARDIOGRAM IN 22 PATIENTS WITH

VALVULAR AORTIC STENOSIS

Preoperative ECG Postoperative ECG

LVH and LVH andGroup No. of Normal LVH Strain No. of Normal LVH Strain Strain

Patients PatientsNo. % No. % No. % No. % No. % No. % No. %

I 5 _- - - 5 100 2 - - 1 50 1 50 - -II 17 7 41 5 29 5 29 16 8 50 3 19 3 19 2 12Total 22 7 32 5 23 10 45 18 8 44 4 22 4 22 2 11

ECG=electrocardiogram; LVH =left ventricular hypertrophy.

and selective angiocardiography were carried outin three cases.Two infants were operated upon as emergency

operations after clinical assessment only. The leftventricular-aortic peak systolic pressure gradientwas 70, 45, and 30 mmHg in the three infantsstudied.Four patients had a bicuspid aortic valve and

one a tricuspid valve. All bicuspid valves pre-sented with rudimentary myxomatous cusps andan eccentric orifice. A coronary artery arose frombehind each cusp. The raphe representing a vesti-gial commissure was located in two instances inthe anterior cusp and in two in the posterior one(Fig. l). In the only infants with a tricuspid valvethe cusps appeared relatively normal with com-plete fusion of the right and non-coronary cuspsand partial fusion of the other two commissures.

Valvular stenosis presented as an isolated car-diac anomaly in two cases; the remaining threeinfants had associated defects, that is, patent duc-tus arteriosus, endocardial fibroelastosis, andmitral insufficiency in two cases each (Table IV).

;.7 I t p I S ly-OY I

LI i \-. 8Z3)

2

7

GROUP II Seventeen patients ranging in age from2 to 24 years are included in this group. Twopatients were below 5 years of age (Table I). Tenwere males and seven females. One patient hadhad a previous operation eight years earlier.Seven patients were symptomatic. Angina waspresent in three cases and episodes of syncopeand easy fatiguability in two cases each (Table II).Electrocardiograms showed a normal pattern inseven patients and left ventricular hypertrophy in10, five of which were associated with a strainpattern (Table III). Haemodynamic studies wereperformed in all instances. The left ventricular-aortic peak systolic pressure gradient ranged from50 to 145 mmHg with an average of 86 mmHg.A bicuspid aortic valve was observed in 13

patients of this group. In nine, the two cusps werelocated anteriorly and posteriorly, one coronaryartery arising from behind each cusp. The raphein seven cases was observed in the anterior cuspand in one in the posterior. One patient presentedtwo false commissures, one in the anterior and theother in the posterior cusp. In four cases, both

tnber of P ueL.2I 1 4

.

t ('.I ciJ --I)..A I.- t, k-. |. a -

FIG. 1. Anatomical variations observed in 17 patients with bicuspid aortic valve.

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Surgical treatment of congenital valvular aortic stenosis

TABLE IVINCIDENCE OF BICUSPID AORTIC VALVE AND ASSOCIATED CARDIAC ANOMALIES IN 22 PATIENTS

WITH VALVULAR AORTIC STENOSIS

Bicuspid ValveGroup No. of PDA EFE Al MI

Patients No. %I 5 4 80 2 2 0 2II 17 13 76 0 0 3 0Total 22 17 77 2 2 3 2

AI=aortic insufficiency; EFE=endocardial fibroelastosis; MI =mitral insufficiency; PDA=patent ductus arteriosus.

coronary arteries arose from the left anterior cuspand the raphe was visible between the two orifices(Fig. 1). In four instances, the aortic valve wastricuspid with thick and nodular margins (Fig. 2).Moderate calcification was observed in two bi-cuspid and two tricuspid valves.Three patients presented with mild aortic in-

sufficiency (Table IV).

OPERATIVE T'ECHNIQUES

Twenty patients have been operated upon usingtemporary cardiopulmonary bypass under normo-thermia or moderate hypothermia at 300C. Since1969 two infants have been operated on usingsurface-induced deep hypothermia and total cir-culatory arrest.A patent ductus arteriosus, when present, was

ligated. An oblique incision was made anteriorlyin the ascending aorta and extended into the non-coronary sinus of Valsalva. With a knife, one tothree incisions were used to open the stenoticvalvular orifice (Fig. 3). The extent and numberof incisions were related to the anatomical find-ings. In those cases in which relatively normal,although fused, cusps could be identified, a pre-cise division of the cusps was made to one milli-

* ~ ~''';Ah'Iit

metre from the aortic annulus. However, in fourinstances, marked deformity of the valve de-manded a more cautious attitude, and a less ex-tensive commissurotomy was performed. Thus aresidual pressure gradient was preferred to signifi-cant valvular incompetence. In one of the caseswith a tricuspid aortic valve an incision was per-formed in only one of the two fused commissures,creating a functional bicuspid valve. In onepatient, residual aortic insufficiency was managedand a valvuloplasty performed.

RESULTS

GROUP I Three of the five infants with valvularaortic stenosis died in the postoperative period(Table V). These three were operated on whenthey had severe congestive heart failure and onewas cyanotic. Two had been operated upon usingdeep hypothermia and circulatory arrest. In thethird case, cardiopulmonary bypass had been used.They all had other associated cardiac anomalies,confirmed at necropsy, consisting of a ligated duc-tus arteriosus in two instances, endocardial fibro-elastosis in two, and an insufficient mitral valve intwo. The immediate cause of death was consideredto be acute heart failure in all three patients.

2 2

...I

ixt t > t * t.) ^I

FIG. 2. Anatomical variations observed in five patients with tricuspid aortic valve, one fromgroup I and four from group 11.

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L. Chiariello, P. Vlad, and S. Subramanian

FIG. 3. Aortic valvotomy perforined with a knife,separating in the bicuspid valve only the larger uni-cusp from the other cutsp. The incision is extendedout to 1 mm (a and b) from the aortic annulus, thusaccepting some degree of residual aortic stenosis.

In only one of the two surviving infants arepreoperative and intraoperative post-repair pres-sure measurements available. The peak systolicleft ventricular-aortic pressure gradient droppedfrom 70 mmHg to 0 (Fig. 4). The two survivingpatients are alive 30 months and two months afteroperation. The first has a fair result because mildsymptoms and clinical evidence of aortic stenosisand insufficiency persist. The follow-up time is tooshort for evaluation in the second child.

GROUP II All 17 patients in this group survivedoperation and were discharged from hospital ingood condition.

Pressure measurements obtained during theoperation after repair showed relief of the ob-struction (Fig. 4). The mean left ventricular peaksystolic gradient decreased significantly (P<0-001)from 86 mmHg (range 145-50 mmHg) to 21 mmHg (range 60-0 mmHg). The only major earlycomplication was haemorrhage requiring reex-

Preop Introop i1 2 3 4 5post repair Years

FIG. 4. Peak systolic left ventricular-aortic pressure

gradients obtained before and after repair in 16patients with congenital valvular aortic stenosis.

ploration in one case. One late death occurredsuddenly in a 20-year-old man three years after a

second operation for correction of residual val-vular stenosis. The first operation had been per-

formed elsewhere at the age of 9 years. Thesecond operation, at the age of 17 years, was

undertaken because of a left ventricular-aorticsystolic pressure gradient of 100 mmHg andelectrocardiographic evidence of left ventricularhypertrophy with a strain pattern. The gradientwas reduced to 40 mmHg but at cardiac catheter-ization, performed two months before his death, ithad increased to 70 mmHg. At the follow-up ex-

amination, 11 (69%) of the 16 survivors wereasymptomatic and three (19%) presented withmild fatiguability. A basal ejection murmur wasdetected in all patients. Clinically, nine had mildto moderate residual aortic stenosis and four hadaortic insufficiency. This was mild in three casesand significant (pulse pressure 65 mmHg) in one,a boy with aortic regurgitation before operation.

TABLE VCLINICAL DATA ON THREE HOSPITAL DEATHS AFTER COMMISSUROTOMY FOR

VALVULAR AORTIC STENOSISPatient Sex Age Preoperative Symptom Associated Lesion Technique Cause of Death

I F 2 d CHF EFE, PDA DH-CCA Heart failure2 M 2 d CHF MI, PDA DH-CCA Heart failure3 F I mth CHF/cyanosis EFE, MI CPBP Heart failure

CHF=congestive heart failure; EFE=endocardial fibroelastosis; PDA=patent ductus arteriosus; DH-CCA=deep hypothermia, cardio-circulatory arrest; MI =mitral insufficiency; CPBP=cardiopulmonary bypass.

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Surgical treatment of congenital valvular aortic stenosis

TABLE VIPOSTOPERATIVE RESULTS IN 22 PATIENTS WITH VALVULAR AORTIC STENOSIS

ResultNo. of

Group Patients Deaths Excellent Satisfactory Fair Poor

No. % No. % No. % No. % No. %

I 5 3 60 - - - - 2 40 - -II 17 1 6 3 18 7 41 4 23 2 12Total 22 4 18 3 14 7 32 6 27 2 9

The postoperative electrocardiogram (Table III)was normal in eight patients, showed left ventri-cular hypertrophy in three, left ventricular hyper-trophy with strain pattern in three, and an isolatedstrain pattern in two. Late haemodynamic studieswere performed in five patients who had symp-

toms or persistent left ventricular strain in theECG (Fig. 4). An increase of the left ventricular-aortic pressure gradient was evident in all of themand was severe in two. The death of one of thesetwo has already been described. The other one

had a second commissurotomy three and a halfyears after the first with early complete disappear-ance of the pressure gradient. Thirty months afterthe reoperation the patient was asymptomatic.

According to the criteria adopted, results were

considered excellent in three cases, satisfactory inseven, fair in four, and poor in two (Table VI).

DISCUSSION

The results of the present series indicate that thesurgical treatment of congenital valvular aorticstenosis has a different prognosis for infants thanfor older patients. In infants, even with the benefitof improved techniques allowing adequate expo-sure (that is, cardiopulmonary bypass, deep hypo-thermia with circulatory arrest), the surgical riskis high.

Three out of five of our infant patients died atoperation. The two infants who survived had a

successful early result, but the future for them isuncertain. Recently, Lakier et al. (1974) postulatedthat aortic stenosis in infants represents a differentspectrum of disease as compared with that occur-

ring in older children. They considered thesepatients as an intermediate group between infantswith aortic atresia and hypoplastic heart syndromeon the one hand and aortic stenosis occurringlater in life on the other. Our series confirms thatthese patients have anatomical and clinical fea-tures which mitigate against successful surgicaltreatment. Before operation all were in severe

congestive heart failure with electrocardiographic

evidence of left ventricular hypertrophy andstrain. Operation was performed as an emergencyprocedure. In four instances (all the infants witha bicuspid aortic valve) the cusps of the valve wererudimentary, myxomatous, and rigid. Surgical re-pair, although providing a more adequate valvularorifice, cannot change the poor quality and mo-bility of the cusps. Associated cardiac anomaliesare other factors which may affect the prognosis.The three infants who died all had additional de-fects, two of them endocardial fibroelastosis con-firmed at necropsy.Although the operative risk is high and the late

results are poor, we feel that surgical palliationstill has to be attempted in selected cases. Vladet al. (1971) report that in isolated valvularstenosis, when surgery could be expected to help,only a minority of patients can survive throughinfancy when treated medically. With endocardialfibroelastosis, prolonged survival is exceptional(Vlad et al., 1971). Since the presence of this ano-maly is not predictable, all babies with aorticstenosis who fail to respond promptly to medicaltreatment should be considered for surgicaltreatment.

Results of surgery in the older age group arein sharp contrast with those in infants. Althoughless than curative, surgical treatment is a safe andeffective procedure. In our series, no hospitaldeaths or major complications occurred exceptfor one reexploration for bleeding. Approximately80% of the patients of group IL became asympto-matic or slightly symptomatic and were able toengage in normal activities. Postoperative electro-cardiograms showed some early improvement inthe asymptomatic patients and support the view ofVlad et al. (1971) that the ECG may return tonormal or near normal over a period of years andmay indicate a good result. Residual aortic insuffi-ciency is a possible postoperative complicationwhich may require a valve replacement later.Special care was taken to stop commissurotomy atleast at one millimetre from the aortic annulus; an

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L. Chiariello, P. Vlad, and S. Subramanian

incomplete relief of the obstruction was preferredto an incompetent valve. In our series only oneboy with preoperative aortic insufficiency showedsignificant regurgitation after surgery.

Relief of the obstruction at the time of surgeryis effective, as demonstrated by early post-repairpressure measurements. These measurements ob-tained under abnormal physiological conditionsshould be accepted with caution. However, thehigh significance (P<0001) of the pressure gradi-ent relief at operation justifies the intraoperativemeasurements at least as a practical guide. Indeed,intraoperative pressure measurements had demon-strated inadequate or incomplete relief of theobstruction in the two patients who presented im-portant late complications (sudden death andsevere aortic stenosis requiring reoperation).In conclusion, in patients beyond infancy, aortic

commissurotomy provides better results than ininfants. Although surgery cannot be consideredcurative in all instances, approximately 60% ofthe cases demonstrated excellent or good results.In the patients with fair or poor results, reopera-tion may be anticipated to prevent further deteri-oration and sudden death. In these patients aorticvalve replacements may become necessary.

REFERENCES

Bernhard, W. F., Keane, J. F., Fellows, K. E., Litwin,S. B., and Gross, R. E. (1973). Progress and prob-lems in the surgical management of congenitalaortic stenosis. Journal of Thoracic and Cardio-vascular Surgery, 66, 404.

Bertranou, E., Davignon, A., Chartrand, C., Kratz, C.,and Stanley, P. (1971). Congenital aortic stenosis:

Follow-up of surgical management. CanadianMedical Association Journal, 105, 583.

Braunwald, E., Goldblatt, A., Aygen, M. M., Rockoff,S. D., and Morrow, A. G. (1963). Congenitalaortic stenosis: I. Clinical and hemodynamicfindings in 100 patients. Circulation, 27, 426.

Coran, A. G. and Bernhard, W. F. (1969). The surgi-cal management of valvular aortic stenosis duringinfancy. Journal of Thoracic and CardiovascularSurgery, 58, 401.

Keith, J. D., Rowe, R. D., and Vlad, P. (1967). HeartDisease In Infancy And Childhood, 2nd edition.MacMillan, New York.

Lakier, J. B., Lewis, A. B., Heymann, M. A., Stanger,P., Hoffman, J. I. E., and Rudolph, A. M. (1974).Isolated aortic stenosis in the neonate. Naturalhistory and hemodynamic considerations.Circulation, 50, 801.

Lambert, E. C., Colombi, M., Wagner, H. R., andVlad, P. (1971). The clinical outlook of congenitalaortic stenosis (valvar and discrete subvalvar)prior to surgery. In The Natural History andProgress in Treatment of Congenital HeartDefects, edited by B. S. L. Kidd and J. D. Keith,pp. 205-213. Thomas, Springfield, Illinois.

Morrow, A. G., Sharp, E. H., and Braunwald, E.(1958). Congenital aortic stenosis. Circulation,18, 1091.

Vlad, P., Wagner, H. R., Colombi, M., and Lambert,E. C. (1971). The clinical outlook of congenitalaortic stenosis (valvar and discrete subvalvar)after surgery. In The Natural History and Pro-gress in Treatment of Congenital Heart Defects,edited by B. S. L. Kidd and J. D. Keith, pp 214-220. Thomas, Springfield, Illinois.

Request for reprints to: Dr. S. Subramanian, Chief,Division of Cardiovascular Surgrry, State Universityof New York at Buffalo, New York, USA.

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