Surgical treatment of atrial septal defect under hypothermiathorax.bmj.com/content/thoraxjnl/19/6/481.full.pdf · S. Zellos ANATOMICAL TYPE OFDEFECT It is customary to classify atrial

Thiorax (19(4), 19, 481.

Surgical treatment of atrial septal defectunder hypothermia

S. ZELLOS'

From the Newcastle Regional Chest Surgery Centre

Since the development of cardiac surgery, defectsof the atrial septum have been recognized withincreased frequency. During the past 15 years,various surgical techniques have been used, andeven to-day the surgical treatment of this lesionis not uniform. In 1948, Murray first closed anatrial septal defect, suturing together the anteriorand posterior atrial walls in the septal plane.S0ndergaard, G0tzshe, Ottosen, and Schultz(1955) introduced his circumclusion suture, appliedafter dissection of the interatrial groove betweenthe cavae and the right pulmonary veins. Bailey,Bolton, Jamison, and Neptune (1953) describedhis technique of atriopexy, and the following yearGross, Pomeranz, Watkins, and Goldsmith (1952)reported his atrial wall operation. Lewis andTaufic (1953) were the first to close an atrial septaldefect with direct vision under hypothermiafollowing the experimental work of Bigelow, andsoon after Swan (1953) applied this technique toa large series. The modem management of atrialseptal defects has been with the use of extra-corporeal circulation, first achieved by Gibbon in1954, by Lillehei, Cohen, Warden, and Varco(1955), and subsequently used by many workers.Although it is now generally agreed that closed

operative techniques are unsatisfactory, there isconsiderable disagreement as to whether hypo-thermia or cardiopulmonary bypass should be themethod of choice for dealing with theuncomplicated, simpler type of atrial septal defect.Many surgeons, for example C. A. Hufnagel (per-sonal communication, 1960), Gross (1962), and anumber of surgeons in this country, recommendbypass for every case of atrial septal defect. Theyconsider the main disadvantage of conventionalhypothermia at 30° C. to be the time limit ofcirculatory arrest thereby imposed, usuallyaccepted as eight to 10 minutes. On the otherhand, this should be an adequate period for simplesuture of an atrial septal defect, and the use of

1 Present address: Georgetown University Medical Center.Washington 7. D.C., U.S.A.

hypothermia avoids heparinization, the consider-able volume of donor blood, and the moreelaborate apparatus involved in the use of bypass.

In the Department of Thoracic Surgery, New-castle upon Tyne between 1956 and 1961, 158patients were treated for an atrial septal defectassociated with or without partial anomalousvenous drainage and valvular pulmonary stenosis.Of these, 133 were operated on under hypo-thermia, and two patients with an ostium primumdefect were treated under extracorporeal circula-tion using the AGA, Senning Crawford apparatus.It is the purpose of this paper to present the'findings and results in this series of cases treated:by this method of open-heart surgery, and todiscuss the place of hypothermia in the surgicaLtreatment of atrial septal defect.

THE SERIES

The age and sex distribution of the patients isshown in Table I.

TABLE IAGE AND SEX OF 135 PATIENTS WITH ATRIAL SEPTAL

DEFECT

Age (years)

Females

Males

Total

0-10

21

19

40

11-20 2

21

18

39

21-30

17

7

24

31-40

18

8

26

4C-S04

2

6

As in other reports in the literature, it will beseen that the lesion was more common in thefemale and that most of the patients were underthe age of 20 years. Atrial septal defect was thecommonest single cardiac anomaly seen in theUnit, and this corresponds with the experience ofPaul Wood (1956), of Bedford and Sellors (1960),and of Nadas (1963).

481

_1__I__I_I_

_-1_ __ __ _

_,____1

on 29 April 2018 by guest. P

rotected by copyright.http://thorax.bm

j.com/

Thorax: first published as 10.1136/thx.19.6.481 on 1 N

ovember 1964. D

ownloaded from

http://thorax.bmj.com/

S. Zellos

ANATOMICAL TYPE OF DEFECT

It is customary to classify atrial septal defects intofour main categories: secundum or fossa ovalisdefect; sinus venosus defect; ostium primumdefect; and atrio-ventricularis communis.

SECUNDUM TYPE This is the commonest type ofatrial septal defect and accounts for 85 to 90%of cases in all published series. It includes twosub-types. The commonest type is the fossa ovalisdefect, which occupies part or whole of the fossaovalis and which may be fenestrated. The inferiorcava form has no lower border so that the inferiorcava opens directly into both atria.

SINUS VENOSUS DEFECT This is embryologicallydistinct; it lies at the upper end of the atrialseptum and is associated with an abnormalconnexion of the right, upper, and middle lobeveins. The fossa ovalis may be intact or maycontain a second defect. We have seen only onecase of sinus venosus defect with a second lowdefect of the foramen ovale variety. Seven othercases of sinus venosus defects were encounteredin the present series. It has been described byLewis (1958), Brock and Ross (1959), andMcCormack, Marquis, Julian, and Griffiths (1960).

OSTIUM PRIMUM DEFECT This defect lies low inthe atrial septum in front of the coronary sinus,and its inferior margin is formed by a ridge ofendocardium between the septal cusps of the atrio-ventricular valves and lying immediately above thesuperior edge of the ventricular septum. Themitral and tricuspid valves are normal. This defectaccounts for 5 to 10% of atrial septal defects.

ATRIO-VENTRICULARIS COMMUNIS This is the leastcommon type of defect and the most complicated.There is an ostium primum and it is associatedwith a cleft in the septal cusp of the mitral valveand sometimes also with a similar cleft in theseptal cusp of the tricuspid valve. In the mostserious abnormality, the ostium primum and thesetwo valve clefts are associated in addition with adefect in the upper part of the ventricular septum.

ASSOCIATED ANOMALIES As in other series, it wasfound that the two commonest associated defectswere pulmonary valvular stenosis and partialanomalous connexion of the pulmonary veins.This occurred in four and in 16 patients respec-tively in this series. A less common associate wasmitral stenosis (Lutemabacher's syndrome), andthere were only two examples. However, Bedford

TABLE IIANATOMICAL VARIETIES OF ATRIAL SEPTAL DEFECT

TOGETHERWITH ASSOCIATED MALFORMATIONS

Type of Defect No.

Simple secundum type defectFossa ovalis 81Inferior type .31

Sinus venosus defect. 8A.S.D. with partial anomalous venous drainage of the

rightlung. 8A.S.D. and pulmonarystenosis.. 4A.S.D. and mitral stenosis.Ostium primum defect.2

Total .. .. .. .. .. .. 135

and Sellors (1960) found an incidence of rheumaticmitral stenosis of 8.5% in atrial septal defects.The anatomical types of the defect aresummarized in Table II.

FUNCTIONAL EFFECTS OF THE DEFECT

The important functional effect of an atrial septaldefect is the occurrence of the left-to-right shuntof blood at atrial level. This shunt occurs becausethe right ventricle is more easily distended, andit has been described by Dexter (1956). As a resultof the shunt, the right ventricular output andpulmonary blood flow are increased, commonlyto two to four times that of the systemic flow.Pulmonary vasodilatation usually prevents aserious rise of pulmonary arterial pressure, butBedford and Sellors (1960) reported the develop-ment of pulmonary arterial obliterative changesin about 12% of cases. The left-to-right shunt isincreased when any of the pulmonary veins con-nect directly to the right side of the heart or tothe cavae. Mitral stenosis increases the left-to-right shunt. The result of the right ventricularoverload is progressive hypertrophy of the rightside of the heart and eventually right-sided failure.

CLINICAL FEATURES

All the patients in this series presented the typicalclinical features of an atrial septal defect firstdescribed by Bedford, Papp, and Parkinson (1941).The soft pulmonary systolic murmur of rela-

tive pulmonary stenosis was associated with fixedsplitting of the pulmonary second sound, and inthose with a fairly large shunt a mid-diastolictricuspid flow murmur was heard. Those withlarge shunts were under-developed and had mildperipheral cyanosis. In uncomplicated cases, thejugular venous pulse had a normal configuration.The right ventricle was hyperdynamic dependingupon the degree of shunt. In cases complicated

482



j.com/


ovember 1964. D

ownloaded from


Surgical treatment of atrial septal defect under hypothermia 483

.A.........

*-; -r^<r w w .i ......................... a .....................-........e..

00~~~~~~~7

1 1 e 1 - . -- ----.AO

no 1t|.vPre-operativehE.G of a patien wit an ostium secnu deet whc shw

-.-...

-. t A. tr....

......,-. -.,.

..

FiG. 1. Pre-operative E.C.G. ofa patient with an ostium secundum defect which showsright axis deviation and right ventricular hypertrophy. There is a QR in Vn,whichis seen in20lg ofpatients. An rSR' inV. would be the more typical finding.

1 11 111 ~~~ ~ ~~~ ~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~AVRAVI{ AVF~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ '77e1'VI V2 'V3 V4 V5 V6

FIG. 2. Typical E.C.G. of a patient with an ostium primum defect. Note the left axis deviation and rSR' in VI.There is evidence of biventricular hypertrophy. The broad P wave in lead II and deeply negative P in lead V,suggest left atrial enlargement.



j.com/


ovember 1964. D

ownloaded from


with pulmonary stenosis, the above signs per-sisted, but the right ventricle was heaving and thesystolic murmur was of grade 3 to 4 with a systolicthrill felt in the pulmonary area.The two patients with ostium primum defects

had the following, in addition to the signs of thosewith uncomplicated atrial septal defects. The leftventricle was hyperdynamic and there was amarked systolic murmur, usually of grade 2 to 3,best heard in the mitral area. This was eitherpansystolic or late systolic.

Fifty of the patients presented without symp-toms. Of the remainder, the commonest present-ing symptom was exertional dyspnoea, present in65 patients, and others complained of recurrentbronchitis, fatigue, or pain and tightness in thechest. Three patients were in cardiac failure whenfirst seen; one of these had an ostium primumdefect. The electrocardiogram showed incompleteright bundle branch block with right axis devia-tion in almost all patients, and in those withelevation of pulmonary arterial pressure or inthose with an associated pulmonary stenosis, therewas E.C.G. evidence of right ventricular hyper-trophy (Fig. 1). In the two cases of primum defect,there was left ventricular hypertrophy and leftaxis deviation (Fig. 2). The characteristic radio-logical features consisted of enlargement of theright atrium, right ventricle, and main pulmonaryartery and considerable pulmonary plethora.These appearances were not seen in those withsmall shunts and were, as would be expected, mostmarked in the patients with the largest shunts.

INDICATIONS FOR SURGICAL INTERVENTION

Our recent increase of knowledge of the naturalhistory of atrial septal defect, the risks of opera-tion, and the results achieved has given us aclearer understanding of the indications forsurgical treatment. We have accepted the prin-ciple that, when a diagnosis of atrial septal defectis made and when the pulmonary/systemic bloodflow ratio is more than 2: 1, the defect should berepaired. We have followed the advice of Bedfordand Sellors (1960), Wood (1956), Brom andKalsbeek (1959), Gross (1962) and others whohave stated that the proper time to close an atrialseptal defect is before the age of 20, i.e., beforethe heart and pulmonary vessels have sufferedirreversible changes. This allows operative treat-ment to be undertaken with the smallest risk andthe greatest chance of subsequent success. Theonly absolute contra-indication to surgery isobstructive pulmonary hypertension with a

vascular resistance exceeding 4 to 5 units and apulmonary to systemic ratio of less than 2: 1.However, in patients over 40 with marked cardiacenlargement, pulmonary hypertension, atrialfibrillation, and cardiac failure, operative mor-tality is high, probably in the region of 15% ormore. Although many of these patients are stillsuitable for operation, the risk is greater and theresults are less good.

PRE-OPERATIVE INVESTIGATIONS In addition tothe standard clinical examination and radiographicfilms of the heart and lungs, all patients had anelectrocardiogram made and underwent cardiaccatheterization. Angiography was performed onlyin cases associated with partial anomalous venousdrainage or pulmonary valvular stenosis. Aleft-to-right shunt was calculated in all patientswith a simple atrial septal defect. Four patientswith associated pulmonary valvular stenosis hada right-to-left shunt. A pulmonary artery meansystolic pressure of 50 mm. Hg was present inonly 12 patients, and none had a significantlyincreased pulmonary vascular resistance.

OPERATIVE TECHNIQUE After induction with thiopen-tone, anaesthesia was continued with a nitrous oxideoxygen mixture, and a relaxant was routinely used.The anaesthetic was maintained through an endo-tracheal tube, and controlled ventilation was usedthroughout. The temperature was monitored withthermocouples in the mid-oesophagus and in the naso-pharynx, and a continuous E.C.G. tracing was main-tained throughout the procedure.Hypothermia was induced by surface cooling

achieved by ice packs placed on the skin in the re-covery room where the patient remained until hisoesophageal temperature had reached 320 C. There-after the patient was transferred to a re-warmingblanket on the operating table through which waterat 37' C. circulated. By this method it was almostalways possible to have the patient's temperature veryclose to 30' C. at the time of inflow occlusion.The operative approach was through the bed of

the fifth rib with division of the sternum. Both in-ternal mammary arteries were divided between liga-tures and the pericardium was cleared. The peri-cardium was opened and retracted to the right overthe lung. The heart was inspected for associatedanomalies and the atrial septal defect was palpatedthrough the atrial wall. Preliminary trans-auricularexploration has not been practised. Tapes were placedaround the cavae, and blood samples were taken fromthe cavae and atria for oxygen saturation measure-ments. A 5 cm. incision was made in the wall of theright atrium within the jaws of a Satinsky clamp.The caval tapes were tightened, and, after a few beatsto allow cardiac emptying, the great arteries were

S. Zellos484



j.com/


ovember 1964. D

ownloaded from


Surgical treatment of atrial septal defect under hypothermia

suP

v. C.

FIG. 3. Atrial septal defect, secundum type, of 20-year-oldpatient closed by suture under direct vision using theinflow-outflow occlusion 300 C. hypothermic technique.

occluded with a clamp through the transverse sinus.The Satinsky clamp was then removed and the rightatrium was cleared of blood by suction. The lowermargin of the defect was sutured first with a 3-0suture of silk. A similar stitch was then passedthrough the upper margin, and the defect was closedwith a double layer of everting stitches (Fig. 3). In thecase of the inferior vena caval defect, care was alwaystaken to ensure closure of the defect to the left of thecava. Before completing closure of the defect, theanaesthetist inflated the lungs, thereby filling the leftatrium with blood and expelling all air from it. Afterclosure of the defect, the inferior caval tape wasreleased to demonstrate that the inferior cava wasflowing into the right atrium. When the right atriumhad filled with blood, the Satinsky clamp was re-applied to the atrial incision, and the superior cavaltape and the transverse sinus clamp were removed.Normal heart action usually resumed spontaneously.The atrial wall was closed with a double evertingsuture. In order to determine whether the defect hadbeen completely closed, 10 minutes after restorationof the circulation blood samples were taken from thesuperior vena cava and from the right and left atriaand were analysed for oxygen content. The peri-cardium was closed and the chest wall was closedwith pleural drainage.

No case of secundum defect has required aprosthesis for its closure, and there has been noobserved breakdown of the suture line.The size and site of the simple secundum defects

were as follows. All were of the fossa ovalisvariety. There were 94 between 3 and 4 cm. insize -occupying the fossa ovalis, eight of whichwere fenestrated; 31 were a large defect of theinferior type of 5 to 7 cm., and 16 of these hadno posterior septal ring. Surface cooling was

applied in all but one patient, in whom veno-venous cooling was performed according toBrock's technique.

Associated partial anomalous pulmonary venousdrainage In all 16 patients with partial anomalouspulmonary venous connexion, operative correctionwas undertaken under hypothermia. Eight patientshad a sinus venosus defect and the characteristicassociated anomaly, so that the right upper andmiddle pulmonary lobes drained into the dilatedlower part of the superior vena cava. In five ofthese the technique of caval partitioning was used(Bahnson, Spencer, and Neill, 1958). In twopatients the technique described by Brock andRoss (1959) was used; in this the crescentic loweredge of the defect is sutured horizontally to theposterior caval wall above the anomalous veins.In the remaining patient the right upper vein wascut off from the superior vena cava and anasto-mosed to the lower vein. During this patient'sconvalescence there was radiological evidence ofpulmonary infarction, but a satisfactory recoverywas made. The importance of occlusion of theappropriate pulmonary artery during the venousanastomosis was not at that time appreciated, andthis may have contributed to the occurrence ofinfarction.

In eight patients there was either partial orcomplete anomalous connexion of t;he right pul-monary veins to the right atrium, and in all ofthese the pulmonary venous drainage was cor-rected by suturing the medial edge of the atrialseptal defect to the right atrial wall in front ofthe anomalous venous openings.

Atrial septal defect combined with pulmonaryvalvular stenosis The four patients who had bothpulmonary valvular stenosis and an atrial septaldefect have had both anomalies corrected at thesame operation through a vertical sternotomy.The valvulotomy was performed first and thecirculation was re-established for 10 minutes toallow cardiac recovery. The atrial septal defectwas then repaired during a second period ofinflow occlusion. The valvular stenosis was mostoften due to a funnel shape, and two cuts weremade converting it to a bicuspid valve. We havethe clinical impression that less insufficiency mayresult if two cuts are made. The pressure gradientacross the valve was recorded before and aftervalvulotomy.Ostium primum defects The two patients whohad a primum defect were operated upon with thestandard technique of extracorporeal circulationcombined with hypothermia at 180 C. bodytemperature. In both, a teflon prosthesis was usedto close the defect, and in one the cleft mitral

485



j.com/


ovember 1964. D

ownloaded from


S. Zellos

A

MITRAL

VALVE

FIG. 4. (A) Operative view of ostium primum defect of11-year-old boy, showing a cleft mitral valve through theatrial septal defect; (B) repair of mitral valve; (C)closure ofatrial defect using teflon prosthesis.

valve was repaired (Fig. 4). Convalescence was

uneventful in both.Arrhythmia during operation The only impor-

tant arrhythmia was ventricular fibrillation, andthis occurred in 18 patients, in all but one immedi-ately after the atrial closure. No patient who ulti-mately developed ventricular fibrillation had a

temperature below 280 C., and most were keptbetween 29 and 300 C. All patients who developedventricular fibrillation had undergone circulatoryarrest for six and a half minutes or longer. Fourpatients died as a result of ventricular fibrillation.In three, normal rhythm was never re-established,and in the fourth, although the rhythm eventuallyreverted to normal after some two hours ofmassage, the patient never regained consciousnessand died from cerebral anoxia. In the remaining16 patients, normal rhythm was re-established bymeans of a period of cardiac massage followed byelectrical defibrillation and sometimes associatedwith re-warming of the heart with warm saline.Ventricular fibrillation occurred more often in our

early experience with hypothermic anaesthesia. Itis well known that the lower the temperature themore likely is the complication; 300 C. is prob-ably the safest lower limit. Other factors inducingventricular fibrillation are the prolongation of theperiod of inflow occlusion and probably the over-

distension of the right side of the heart by thesimultaneous release of the venae cavae. Ourexperience indicated that there is good correla-tion between low temperature, period of inflowocclusion, and ventricular fibrillation.

The use of coronary perfusion for protectingthe myocardium during the inflow occlusion hasnot been practised; we do not believe that coro-nary perfusion is necessary. Experience with extra-corporeal circulation has shown that 10 to 15minutes hypoxic cardiac arrest is well toleratedby the myocardium. If cardiac arrest of longerthan eight minutes is required, then the inter-mittent inflow occlusion is advisable. As experi-ence has grown, the incidence of ventricularfibrillation has decreased, so that it is now a rareoccurrence.

OPERATIVE MORTALITY There were six deaths inthe series. Apart from one 6-year-old child, allthe deaths occurred in adults, and the commonestcause of death was ventricular fibrillation occur-ring during operation. As detailed above, threepatients died on the operating table with irre-versible ventricular fibrillation, and a fourth diedof cerebral anoxia after a long period ofventricular fibrillation. One 42-year-old patientdied of cerebral embolism on the day afteroperation, never having regained consciousness,and the remaining patients died on the seventhpost-operative day of staphylococcal septicaemiauncontrolled by antibiotics.

POST-OPERATIVE COMPLICATIONS Apart from thefatalities, the only important complication wasempyema, which developed in three patients, twoof whom subsequently needed drainage by ribresection. Atrial fibrillation was a common occur-rence and appeared post-operatively in more thanhalf of the patients. It was usually of short dura-tion, but in three patients it persisted for sixmonths. In two, a sinus tachycardia of 160 perminute persisted for six months. Two patients hadtransient atrial flutter, and c,ne had heart blockfor 24 hours.

DISCUSSION

Though the surgical management of atrial septaldefect has become increasingly satisfactory, surgi-cal opinion is still divided as to whether the bestapproach is visual closure of the defect under300 C. hypothermia or with the use of extra-corporeal circulation.

Several clinics in the United States of Americaand in Europe have effectively used moderatehypothermia alone without the additional use ofcardiopulmonary bypass for the surgical correc-tion of an atrial septal defect and pulmonaryvalvular stenosis.

486



j.com/


ovember 1964. D

ownloaded from


FIG. 5. Postero-anterior view of the chest showing the cardiac silhouettes of a patient who underwent open-heartsurgery for the closure of a secundum type defect: (above) pre-operative, (below) two years post-operatively.

.;Z:...

.-i



j.com/


ovember 1964. D

ownloaded from


S. Zellos

Although an efficient pump oxygenator foropen-heart surgery has been in use in our clinicsince 1959, we have continued to use the inflowocclusion technique under 300 C. hypothermia forall patients with an atrial septal defect of thesecundum variety, whether or not it is associatedwith partial abnormal insertion of the pulmonaryveins and pulmonary valvular stenosis.When the clinical, radiological, E.C.G., and

haemodynamic studies were all consistent with thepresence of a secundum defect, this diagnosis wasinvariably substantiated at operation. If any of thefeatures suggest a primum defect, operation shouldbe performed using extracorporeal circulation.We believe that the surgical correction of an

atrial septal defect of the secundum variety caneasily be achieved under 300 C. hypothermiawithout the use of prosthetic materials. Theexpulsion of air from the left atrium might beeasier with the use of cardiopulmonary bypass butthis has not been a problem in our series.The unexpected discovery of partial anomalous

venous drainage at operation does not give caus-for concern, for the operation is the same, and thetechnique described by Brock and Ross (1959),Bahnson et al. (1958), and Risch and Hahn (1958)can be used effectively with minimal operativerisk and good results. When pulmonary valvularstenosis is present it is not necessary to use theheart-lung machine. The hypothermia techniquewith intermittent inflow occlusion can be usedsuccessfully for the correction of both anomaliesin one operation within the time limits imposedby hypothermia at 300 C.Our experience indicates that the technique of

inflow occlusion under 300 C. hypothermia has anacceptable low operative mortality with goodclinical results and is applicable to all atrial septaldefects of the secundum variety with the associatedanomalies.

This method has the merits of simplicity andeconomy, and requires minimal personnel; in thisrespect it offers distinct advantages over extra-corporeal circulation. We believe that cardio-pulmonary bypass is necessary for the correctionof the most complicated defects of the primumvariety.

After operation almost all symptomatic patientsnoticed an improvement in their physical conditionwith a lessening or disappearance of breathlessnessand fatigue. Underdeveloped children showed animprovement in growth, weight gain, and exercisetolerance. Clinical examination revealed thatsplitting of the second sound usually becamecloser on expiration but in some cases did notbecome single on expiration. The tricuspid dia-

stolic murmur always disappeared, and a pul-monary systolic ejection sound, when present,always persisted. Post-operative cardiac catheter-ization was performed in five patients two yearsafter operation. In none of these patients weresigns of communication between the atria found.Radiological examination showed that large heartsbecame smaller in one-third of the cases, and theright atrium was also less prominent (Fig. 5). Inthe remaining patients the size of the heart wasunchanged. Of the patients who developed atrialfibrillation and atrial flutter, post-operative E.C.G.reports showed that both the atrial fibrillation andthe atrial flutter had reverted to normal rhythmwithin 48 hours in the majority of patients. Allpatients were treated with digitalis. However,normal reversion in three patients took sixmonths, and in one patient paroxysmal tachy-cardia occasionally develops.

SUMMARY

The technique of inflow occlusion under 30° C.hypothermia was adopted for direct visual correc-tion in 133 consecutive cases of atrial septal defectof the secundum variety and the associatedanomalies.The use of extracorporeal circulation combined

with hypothermia was reserved for the repair oftwo cases of ostium primum defects.The over-all operative mortality was 4%.Post-operative evaluation showed that the results

have been good in almost all patients, includingthose with pulmonary hypertension.

Since an ostium primum defect requires cardio-pulmonary bypass for its closure, the pre-operativerecognition of the defect is highly desirable in theselection of patients for operation and in planningthe procedure itself.The information derived from the clinical

examination and appropriate diagnostic studieshas been found to be consistently accurate in thepre-operative differentiation of the primum fromthe secundum defect. Therefore, the unexpecteddiscovery of a primum defect at operation was nota problem.

In our experience, open-heart surgery under300 C. hypothermia for the repair of an atrialseptal defect of the secundum type and the associ-ated anomalies is a safe and practical techniqueand effectively corrects the anomaly with minimalrisk.

My thanks are due to Mr. George Mason, seniorsurgeon who operated on these cases, to Dr. Joan

488



j.com/


ovember 1964. D

ownloaded from


Surgical treatment of atrial septal defect under hypothermia

Millar, senior anaesthetist, and to Dr. C. B.Henderson, cardiologist to the Regional ThoracicSurgical Clinic at Shotley Bridge General Hospital,Newcastle upon Tyne, for their help and advice inreporting these cases. I also wish to thank Dr.Khakoo for the follow-up of the cases.

REFERENCES

Bahnson, H. T., Spencer, F. C., and Neill, C. A. (1958). Surgicaltreatment of thirty-five cases of drainage of pulmonary veinsto the right side of the heart. J. thorac. Surg., 36, 777.

Bailey, C. P., Bolton, H. E., Jamison, W. L., and Neptune, W. B.(1953). Atrio-septopexy for interatrial septal defects. Ibid., 26,184.

Bedford, D. Evan, Papp, C., and Parkinson, J. (1941). Atrial septaldefect. Brit. Heart J., 3, 37.

-and Sellors, T. Holmes (1960). Atrial Septal Defect, In ModernTrends in Cardiology, ed. A. M. Jones, p. 138. Butterworths,London.

Brock, R., and Ross, D. N. (1959). The sinus venosus type of atrialseptal defect. Guy's Hosp. Rep., 108, 291.

Brom, A. G. and Kalsbeek, H. (1959). Die chirurgische Behandlungder Pulmonalstenose. Thoraxchirurgie, 7, 229.

Dexter, L. (1956). Atrial septal defect. Brit. Heart J., 18, 209.

Gibbon, J. H., Jr. (1954). Discussion on controlled cross circulationfor open intra-cardiac surgery. J. thorac. Surg., 28, 343.

Gross, R. E. (1962). Atrial septal defects of the secundum type.Progr. cardiovasc. Dis., 4, 301.Pomeranz, A. A., Watkins, E., Jr., and Goldsmith, E. I. (1952).Surgical closure of defects of the interauricular septum by useof the atrial well. New Engl. J. Med., 247, 455.

Lewis, F. J. (1958). High defects of the atrial septum. J. thorac.Surg., 36, 1.and Taufic, M. (1953). Closure of atrial septal defects with theaid of hypothermia, experimental accomplishments and reportof one successful case. Surgery, 33, 52.

Lillehei, C. W., Cohen, M., Warden, H. E., and Varco, R. L. (1955).The direct-vision intracardiac correction of congenital anomaliesby controlled cross circulation. Surgery, 38, 11.

McCormack, R. J. M., Marquis, R. M., Julian, D. G., and Griffiths,H. W. C. (1960). Partial anomalous pulmonary venous drainageand its surgical correction. Scot. med. J., 5, 367.

Murray, G. (1948). Closure of defects in cardiac septa. Ann. Surg.,128, 843.

Nadas, A. S. (1963). Pediatric Cardiology, 2nded., p. 463. Saunders,Philadelphia and London.

Risch, F. and Hahn, C. (1958). The technique of surgical correctionof anomalies of the pulmonary veins in a series of twenty-fivecases. Thorax, 13, 251.

Sondergaard, T., Gotzsche, H., Ottosen, P., and Schultz, J. (1955).Surgical closure of interatrial septal defects by circumclusion.Acta chir. scand., 109, 188.

Swan, H. (1953). Surgical closure of interauricular septal defects.J. Amer. med. Ass., 151, 792.

Wood, P. (1956). Diseases of the Heart and Circulation, 2nd ed.,p. 370. Eyre and Spottiswoode, London.

489



j.com/


ovember 1964. D

ownloaded from


Documents

Surgical treatment of atrial septal defect under hypothermiathorax.bmj.com/content/thoraxjnl/19/6/481.full.pdf · S. Zellos ANATOMICAL TYPE OFDEFECT It is customary to classify atrial