Selective left heart angiocardiography by the transseptal route

Selective Left Heart Angiocardiography by the Transseptal Route* EUGENE BRAUNWALD, M .D ., EDWIN

C.

BROCKENBROUC,H, M .D .,t TAMES

and S . DAVID Bethesda, Maryland

J . ROI .AND FOLSE, M .D .t

S

FI .ECTIVE angiocargiography is now firmly

established as a technic of major importance in the diagnosis of congenital and acquired heart diseases . The applications of this technic in the assessment of abnormalities involving the left side of the heart have been somewhat limited because of the hazards and technical difficulties associated with the injection of contrast substance into these chambers . The safety and reliability of the transseptal method of left heart catheterization suggested the use of this approach for left heart angiocardiography [1] . Recently, the transseptal technic was modified to permit the selective injection of contrast substance into the left atrium or left ventricle [2] . Selective angiocardiograms have been performed by this method in sixty patients and the present report constitutes a description of this new technic and of its clinical applications . EQUIPMENT' AND TECIINTC

Adult patients undergoing transseptal left heart catheterization and angiocardiography are given pentobarbital orally and children over eight or ten years receive a mixture of meperidine, Phenergan® and promazine . Younger children are usually studied under light general anesthesia [3] . Following percutaneous puncture of the right femoral vein, right heart catheterization is performed and following this, transseptal left atrial puncture is accomplished by the technic described in detail in a previous report [3] . Briefly, a specially curved radiopaque polyethylene or Tefton§ catheter is introduced into the right femoral vein . The catheter is passed into the right atrium, the transseptal needle is introduced into the catheter and the interatrial septum is punctured in

L.

TALBERT, M .D .,'+

ROCKOFF, M .D .

the region of the fossa ovate [1] . After entry of the tip of the needle into the left atrium, the catheter is advanced with the needle until both tips lie within the cavity of the left atrium . The catheter is then passed over the end of the needle and is directed into the left ventricle, and the needle is then withdrawn . If the clinical and hemodynamic data indicate the need for angiocardiographic visualization of the left side of the heart, the catheter may he positioned either in the left atrium or ventricle for the injection of contrast material, It is important that the catheter tip lie freely within the cavity of the chamber to prevent extravasation of the contrast material into the myocardium . Several side holes in the distal 1 .5 cm . of the catheter facilitate the rapid delivery of the contrast medium, and minimize the possibility of recoil of the catheter and the hazard of intramyocardial injection . The contrast material ordinarily employed, DitriokonO brand of sodium diprotrizoate and diatrizoate injection, is administered in a dosage of 0 .8 to 1 .0 nil. per kg. of body weight . The injection is made through the catheter by means of a Gidlund (Elemae') power-injecting syringe at a pressure of 5 to 10 kg . per cm' . Adult patients are awake and maintain a deep inspiration during the injection . Infants and children are maintained in a position of deep inspiration by the anesthesiologist . Roentgenographic exposures are made in the lateral and frontal projections with the aid of a Schonander ® biplane serialographic unit at a rate of 4 to 6 exposures per second, (it with a 16 nun. Kodake tine camera photographing a PickerMorgan' ) image orthocon at a rate of 30 exposures per second . RESULTS

Transseptal left heart angiocardiography has been carried out in sixty patients . The dye was injected into the left ventricle in forty-two patients and into the left atrium in thirteen

§ Manufactured by U . S. Catheter and Instrument Corp ., Glens Falls, New York .

"From the Cardiology Branch and the Clinic of Surgery, National Heart Institute and the Diagnostic Radiology Department, Clinical Center, National Institutes of Health, Bethesda, Maryland, Manuscript received November 10, 1961 . t Present address : University of Washington Medical School, Seattle, Washington . Present address : Department of Surgery, Johns Hopkins Hospital, Baltimore, Maryland . vot. . 33, AUGUST 1962

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patients . During the injection the left ventricular myocardium was perforated by the catheter tip in one patient, resulting in the extravasation of a small amount of contrast material into the myocardium and pericardial space . Fortunately, there were no sequelae ; the patient had no discomfort during or after the injection ; no arrhythmia occurred ; there were no signs of intrapericardial bleeding ; and serial electrocardiograms revealed no changes . This complication was probably avoidable since later review of the scout films suggested that the tip of the catheter was in apposition with the myocardium at the apex of the ventricle rather than lying freely within the ventricular cavity . In two other patients ventricular fibrillation developed immediately following the injection of the test dose (2 ail .) of the contrast substance . Both patients were immediately restored to sinus rhythm with external countershock without sequelae . These two reactions are considered to represent instances of sensitivity to Ditriokon rather than complications of the transseptal technic and recently we have changed the contrast substance to Renovist . COMMENTS

In many patients with malformations involving the left side of the heart, the clinical examination and the measurement of pressures in the left atrium and ventricle, and the recording of indicator-dilution curves provide sufficient information to formulate a diagnosis and a rational plan of therapy . In some patients, however, more precise characterization of the lesion is necessary . Angiocardiography can provide valuable anatomic information and is an important adjunct to the usual cathetcrization studies [4] . Intravenous angiocardiography, despite its acknowledged limitations, still enjoys widespread popularity because of its safety and the ease with which it may be performed . While adequate visualization of the right side of the heart may often be obtained by this means, further dilution of the contrast medium as it passes through the pulmonary circulation, and the opacification of adjacent structures reduce the value of this technic for visualization of the left atrium and ventricle . Introduction of the contrast material directly into the pulmonary artery in order to visualize the left side of the * 35 per cent Na-diatrizoate and glucamine diatrizoate .

34 .3

per cent methyl

el al .

heart represents an improvement over the intravenous technic, but is less satisfactory than direct injection into the chamber under study . The approaches previously employed for selective contrast radiography of the left side of the heart were retrograde left ventricular catheterization and direct transthoracic needle puncture of the left atrium or ventricle . Retrograde catheterization of the left ventricle from the aorta remains a useful technic for the performance of left ventricular angiocardiography in the presence of a normal aortic valve or one that is incompetent [5-7] . In patients with obstruction to left ventricular outflow, however, it may be difficult or even impossible to pass the catheter across the stenotic orifice . The catheter cannot usually be manipulated into the left atrium by this technic, and therefore contrast substances cannot be injected directly into this chamber . Percutaneous puncture of the left ventricle has also been employed for contrast radiography but is associated with significant risk [8,9] . Also, left atrial opacification is not possible with this technic unless gross mitral regurgitation is present . Selective injections into the left atrium may be performed by transthoracic puncture of this chamber, but this technic also carries the hazards of external puncture of the heart [10] and is contraindicated when the left atrium is not significantly enlarged . Experiences with transseptal left heart catheterization in 600 patients studied at the National Heart Institute have demonstrated that this procedure may be performed with ease and safety [1,3] . This technic has recently been modified so that the catheter which is passed into the left side of the heart is of sufficient caliber to permit rapid injection of a large quantity of contrast Indium . Thus, when the hemodynamic data indicate the potential usefulness of such a study, selective left heart angiocardiography or cineangiocardiography may be carried out during the course of the left heart catheterization . This obviates the need for a second procedure and the additional hazards and discomforts which might be associated with it . Other workers [11,12] have also reported the usefulness of transseptal left heart angiocardiography . The following group of patients has been selected to illustrate the applications of transseptal left heart angiocardiography in the assessment of various lesions involving the left side of the heart and great vessels . AMERICAN JOURNAL OF MEDICINE

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Fm . 1 . Case i . Transseptal left ventricular angiocardiogram in patient with congenital valvular aortic stenosis . A and B, frontal projection . C and D, lateral projection . The dome-shaped, thickened aortic valve is indicated by the arrows in D. Poststenotic dilatation of the aorta is also evident . Ao = aorta ; LV = left ventricle . CLINICAL REPORTS Obstruction to Left Ventricular Outflow CASE 1 . J . G . (No . 03-50-96) is an eleven year old boy in whom a heart murmur had been detected at the age of five years . He had no symptoms, however, until the year prior to his admission to the National Heart Institute, when he became aware of precordial pain following exertion . On examination, a left ventricular lift was present and a systolic thrill was palpable at the base of the heart . A grade 4/6 systolic ejection murmur was heard best at the aortic area VOL . 33, AUGUST 1962

and radiated along the carotid vessels ; a soft blowing diastolic murmur was present along the left sternal border . Left ventricular hypertrophy was evident on the electrocardiogram and the chest roentgenogram . Right heart and transseptal left heart catheterization were carried out and the peak systolic pressure gradient between the left ventricle and brachial artery was found to be only 35 mm . Hg . A selective angiocardiogram with left ventricular injection demonstrated the obstruction to be valvular in location and confirmed the presence of significant left ventricular enlargement . (Fig . 1 .) Moderately severe stenosis

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Transseptal Angiocardiography-Braunwald et al. subaortic stenosis is important since the criteria for operation and the surgical technic for correction of these two lesions are also quite different [14] . An example of a selective angiocardiogram with left ventricular injection in a twenty-eight year old woman with congenital subaortic stenosis of the discrete fibrous variety is reproduced in Figure 2 . This diagnosis was subsequently confirmed at open operation . Left ventricular angiocardiography in patients with obstruction to left ventricular outflow not only delineates the site of the obstruction but also indicates the degree of narrowing, the thickness and mobility of the aortic cusps, the thickness of the left ventricular wall, and the degree of dilatation of the left ventricular cavity .

Hypertrop/uc Subaortic Stenosis A heart murmur was discovered in this patient (C . F .) at three months of age . Progressive fatigability and exertional dyspnea developed during childhood and there was roentgenographic evidence of left ventricular hypertrophy . Physical examination at the age of eleven years revealed a left ventricular lift and a grade 4/6 systolic ejection murmur which was maximal along the left sternal border and apex of the heart . The electrocardiogram revealed marked left ventricular hypertrophy, and the chest roentgenogram showed enlargement of the left ventricle without dilatation of the ascending aorta . At transseptal left heart catheterization the patient was found to have a systolic pressure gradient of 185 mm . Hg within the left ventricular outflow tract, and the left ventricular angiocardiogram showed marked narrowing of the outflow tract during systole with relaxation during diastole, confirming the clinical impression of idiopathic hypertrophic subaortic stenosis . At the time of open heart operation, a subaortic ventriculomyotomy [74] was performed by Dr. A . G . Morrow . When the patient was examined eight months later, he was found to be clinically improved and at the time of postoperative transseptal left heart catheterization, it was found that the intraventricular pressure gradient had been reduced to 30 turn . Hg . However, the angiographic features characteristic of hypertrophic subaortic stenosis have persisted . (Fig . 3 .) CASE it .

Fro . 2 . Transseptal left ventricular angiocardiogram in a patient with discrete fibrous subvalvuiar stenosis There is some reflux of contrast material into an enlarged left atrium (LA) . AV = aortic valve ; RCA = right coronary artery ; SVS = site of subvalvular stenosis . of the aortic valve, presumably congenital in origin, was noted at operation .

Comment Although the hemodynamic data in this patient indicated that obstruction of only a mild degree was present, he was symptomatic and bad appreciable left ventricular hypertrophy . Such a disproportion between the pressure gradient and the degree of ventricular enlargement is frequently observed in patients with hypertrophic subaortic stenosis [13] . However, in this patient the left ventricular angiocardiograms conclusively demonstrated the presence of valvular stenosis . In patients with a pressure gradient between the left ventricle and aorta, the roentgenographic demonstration of calcium in the region of the aortic valve almost certainly indicates the presence of val vlar stenosis . In the absence of calcification, however, the stenosis could be one of several anatomic types, and the localization of the site of obstruction is essential for the proper selection of patients for operation . The correction of supravalvular stenosis, for example, is generally associated with a greater risk than the correction of congenital valvular stenosis of the same severity, and different surgical technics are required . The distinction between hypertrophic subaortic stenosis and discrete fibrous

Comment : Systolic narrowing of the left ventricular outflow tract is one of the features of hypertrophic subaortic stenosis which make it possible to distinguish this lesion from the more usual forms of obstruction to left ventricular outflow . Selective left ventricular angiocardiography is the only method short of AMERICAN JOURNAL OF MEDICINE

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Fm . 3 . Case u . Left ventricular angiocardiogram obtained eight months after operation for hypertrophic subaortic stenosis . The arrows delineate the width of the outflow tract in diastole (A and C), and in systole (B and D) . The oblique arrow in D indicates the position of the normally appearing aortic valve (Ao.V'.) . surgical exploration by which this systolic obstruction may be demonstrated [131 .

Left Atrial Angiography in Mitral Stenosis CASE in, F . M . (No. 03-20-07), a forty-five year old white man with rheumatic heart disease, was admitted to the National Heart Institute with a history of progressive disability and of a recent episode of congestive heart failure . Physical examination revealed the classic findings of pure mitral stenosis . The electrocardiogram showed atrial fibrilla-

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tion and digitalis effect, and the chest roentgenogram demonstrated left atria) enlargement and calcification in the region of the mitral annulus . At catheterization the pulmonary artery pressure was slightly elevated (33/19 mm. Hg), the mean left atrial pressure was 15 mm . Hg and it exhibited the contour considered typical of Urinal stenosis ; the mean diastolic pressure gradient across the mitral valve was 10 mm . Hg . To exclude the possibility of thrombotic material within the atrium, a selective left atrial angiocardiogram was performed . (Fig . 4 .) The left atrium filled completely and



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et al .

4B

FIG . 4 . Case m . Transseptal left atrial angiocardiogram in the lateral projection (left) and in the anteroposterior projection (right) . No filling defects are seen in the left atrium (LA) . The arrows indicate the jet of contrast material below the mitral orifice . The thickened mitral valve leaflets are seen just above the arrows .

the jet of contrast material traversing the stenotic mitral valve was evident . At operation the left atrium was free of clot and a thickened and fibrotic valve was opened with a combined digital and transventricular commissurotomy . Comment: It is generally accepted that patients with left atrial thrombi may be operated upon more safely using the open heart technic than by closed mitral valvulotomy. Preoperative left atrial angiocardiograms may prove helpful in patients with a history of long-standing atrial fibrillation and of previous embolization, since the incidence of clot is highest in them . Figure 5 is a preoperative angiocardiograin obtained by the transseptal method in a woman with mitral stenosis and atrial fibrillation who had a history of three distinct embolic episodes . No filling defects were evident either in the left atrium or in the atrial appendage . In addition, this study also provided considerable information regarding the function of the mitral valve itself. Figure 5A, exposed during ventricular systole in the left posterior oblique projection, outlines the thickened mitral valve leaflets, whereas Figure 5B, exposed during ventricular diastole, shows that these leaflets maintain considerable mobility, and form a funnelshaped opening during this phase of the cardiac

cycle . As has recently been shown by Ross and associates [12], left atrial cineangiography is particularly helpful in the evaluation of the structure and function of the mitral valve . Exclusion of Mitral Regurgitation CASE Iv, T . Z . (No . 10-10-40), a twelve. year old girl, had a grade 4/6 holosystolic murmur at the cardiac apex and evidence of left ventricular hypertrophy on the chest roentgenogram . Right heart catheterization on two occasions demonstrated no hemodynamic abnormalities and the presumptive diagnosis was congenital mitral regurgitation . Transseptal left heart catheterization showed that the pressures in the left atrium and ventricle were normalA selective angiocardiogram with left ventricular injection showed no opacification of the left atrium, thus excluding the presence of mitral regurgitation. (Fig . 6 .) Although the position of the left ventricle was more posterior than usual, the patient's heart murmur remains unexplained .

Comment : The presence of a prominent apical pansystolic murmur generally suggests the presence of significant mitral regurgitation . Selective angiocardiography with left ventricular injection is a very sensitive technic for determining the presence or absence of this lesion . This approach is particularly helpful in patients AMERICAN JOURNAL OF MEDICINE



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et al .

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5B

FIG . 5 . Left atrial angiocardiogram in a patient with mitral stenosis, exposed in the left posterior oblique projection . A = systole ; B = diastole ; MV = mitral valve ; App = left atrial appendage ; PM = hypertrophied papillary muscle .

6 . Case tv . Transseptalleft ventricular angiocardiogram . There is no opacification of the left atrium and the left ventricle (LV) is displaced posteriorly . FIG,

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7 . Case v . Selective angiocardiograms in the anteroposterior projection in patient with coaretation of the aorta (white arrow) and aneurysmal dilatation of the sinuses of Valsalva (black arrows) . The injection was made into the left ventricle (LV) . Ao = aorta . FIG .

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Diagnosis of Lesions of the Ascending Aorta and Aortic Arch CASE V . Shortly after his birth D . C . (No . 03-43-92), a thirteen year old schoolboy, was noted to have a heart murmur . His only complaint was mild exertional dyspnea, and he was referred to the National Heart Institute because of the persistent heart murmur and the diminished pulses in his lower extremities . On physical examination left ventricular enlargement was evident and a grade 4/6 harsh systolic murmur was present along the left sternal border and over the back ; the femoral pulses were barely palpable . The chest roentgenogram and electrocardiogram revealed left ventricular hypertrophy . Transseptal left heart catheterization demonstrated a left ventricular pressure of 140/12 mm . Hg . There was no pressure gradient across the aortic valve, but a large pressure gradient between the brachial artery (140/80 mm. Hg) and the femoral artery (90/65 mm . Hg) was present . A moderately severe coarctation of the descending aorta and previously unsuspected aneurysmal dilatation of the sinuses of Valsalva were demonstrated by selective left ventricular angiocardiography . (Fig . 7 .) Subsequently the patient underwent successful surgical correction of the coarctation.

FIG . 8 . Case vi . Lateral view angiocardiogram in patient with a functionally single ventricle (VENT.) .

with rheumatic mitral valve disease in whom the coexistence of stenosis and regurgitation may make the assessment of valve function difficult . A combination of pressure and flow measurements across the mitral valve and of left atria) or left ventricular angiocardiography, all carried out by the transseptal technic, has been helpful in characterizing the anatomic and physiologic abnormalities present in such patients . It is of interest that left ventriculoatrial regurgitation of contrast material is not usually induced by the transseptal catheter in patients in whom the mitral valve is competent . However, the catheter itself may occasionally recoil from the left ventricle into the left atrium during the injection, and in this manner opacify the left atrium and thus prohibit the detection of mitral regurgitation .

Comment . Injection of contrast material into the left atrium or left ventricle produces excellent opacification of the thoracic aorta and is useful in the demonstration of lesions such as aorticopulmonary communications, anomalies of the aortic arch, and aneurysms and occlusive lesions of the great vessels . The transseptal approach obviates the need for retrograde arterial catheterization, which is often difficult in infants and small children and which may be hazardous in adults with obstructive lesions of the aorta . In this patient angiocardiography provided knowledge of the exact position and severity of the coarctation, the degree of formation of collateral vessels, and indicated that the segments of aorta immediately proximal and distal to the coarctation were suitable for direct anastomosis . Aneurysmal dilatation of the sinuses of Valsalva has been described previously in patients with coarctation of the aorta [15] and in one instance has been observed to regress following successful resection of the coarctation [16] .

Assessment of Ventricular Septal Defects CASE vt .

G . S . (No. 03-65-32), a three and a half old boy, was known to have a heart murmur since the age of one year . Although he was under-

year

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FsG . 9 . Left ventricular angiocardiogram in a patient with a ventricular septal defect . RV = right ventricle . The vertical arrows in the film on the left outline the margins of the defect . The film on the right was exposed 1 second later and shows filling of the aorta (Ao) and pulmonary artery (PA) . The lower margin of the defect is outlined by the arrow on this film . developed, he remained asymptomatic . On examination the findings were characteristic of a ventricular septal defect with pulmonary hypertension . Right heart catheterization showed that (1) a large left-toright shunt entered the right ventricle (pulmonary :systemic flow ratio = 4 .8 :1 .0), (2) the pulmonary and systemic arterial pressures were equal, and (3) a small right-to-left shunt originated from the right ventricle . A transseptal left ventricular angiocardiogram revealed a single large ventricular chamber in which the ventricular septum could not be discerned and from which both great vessels arose . (Fig . 8 .) Thus this patient is considered to have either a single ventricle or a large defect involving virtually the entire ventricular septum . In either case the risk of complete repair in this child would appear to be high . In order to diminish the pulmonary blood flow and the pulmonary artery pressure, Dr . A . G . Morrow constricted the pulmonary artery by means of a nylon band. Comment : When the shunt through a ventricular septal communication is primarily from left-to-right, only rarely will injection of contrast material into the right side of the heart outline the defect . At the present time we study the majority of patients with this diagnosis by percutaneous right heart catheterization through the right femoral vein . After the presence of a shunt entering the right ventricle is confirmed, and if the clinical and hemodynamic findings suggest that closure of the defect is indicated, VOL .

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transseptal left heart catheterization and left ventricular angiocardiography are carried out . In this manner the defect may be localized and its size defined . The plan of management of a discrete opening in the ventricular septum which lies just below the aortic valve, shown in Figure 9, differs from that of a functionally single ventricle . (Fig . 8 .) SUMMARY

A technic for performing selective left atrial and left ventricular angiocardiography by means of percutaneous transseptal left heart catheterization is described and the results of such studies performed in sixty patients arc presented . The clinical applications of this technic in the study of patients with various forms of obstruction to left ventricular outflow, various types of mitral valve lesions, defects of the ventricular septum and anomalies of the aortic arch are discussed in detail . REFERENCES 1 . Ross, ii, JR ., BRAUNWALD, E . and MORROW, A. G.

Left heart catheterization by the transseptal route : a description of the technic and its applications . Circulation, 22 : 927, 1960 . 2 . BROCKENBROUGH, E. C . and BRAUNwALn, E . A new technic for left ventricular angiocardiography and transseptal left heart catheterization . Am. J. Cardrof, 6 : 1062, 1960 . 3 . BROCKENBBDUGH, E . C., BRAUNWALD, E. and Row,

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J ., JR . Transseptal left heart catheterization : a review of 450 studies and description of an improved technic. Circulation, 25 : 15, 1962 . 4. KJELLBERG, S . R., MANNHEISaR, E ., Ruonz, V . and JONSSON, B. Diagnosis of Congenital Heart Disease, 2nd ed. Chicago, 1958 . The Year Book Publishers, Inc . 5 . AMPLATZ, K ., ERNST, R ., LESTER, R. G., LILLEHEI, C . W. and LILLIE, A . Retrograde left cardioangiography as test of valvular competence . Radiology, 72 : 268, 1959 . 6. TORY, G. and GARVSI, G. F . Left cardiac ventriculography by means of percutaneous catheterization of Ea femoral artery in the diagnosis of mitral insufficiency. Acta radial., 54 : 170, 1960 . 7 . STARoaiN, 0. E., Lrt-rwANx, D ., SANDERS, C. A. and TURNER, J. D . Retrograde catheterization of the left ventricle and angiography in the diagnosis of mitral valve disease . New England J. Med., 265 : 462, 1961 . 8. BJORE, V. 0 ., CDLL}IED, I ., HALLEN, A., LoDIN, H . and MALERS, E. Sequelae of left ventricular puncture with angiocardiography . Circulation, 24 : 204, 1961 . 9 . LEHMAN, J. S. Cardiac ventriculography . Frogr. Cardiaease. Dis., 2 : 52, 1959.

et al .

10 . BJin, V. 0. and Loom, H . Left heart catheterization and selective left atrial and ventricular angiography in the diagnosis of mitral and aortic valve disease . Progr . Cardiocacc. Dis ., 2 : 116, 1959 . 11 . STEINHART, L. and ENDRYS, J . Die transeptale lavographie. Fortschr . Rontgenstr ., 93 : 753, 1960 . 12 . Ross, R . S., CRILEY, J. M. and MORGAN, R . H . Cineangiocardiography in mitral valve disease . Traits . A . Am . Phys.,74 : 271, 1961 . 13 . BRAUNwALD, E ., MORROW, A . G ., CORNELL, W. P., Avoan, M. M . and HILmsH, T. F . Idiopathic hypertrophic subaortic stenosis : clinical, hemodynamic and angiographic manifestations . Am. J. Med., 29 : 924, 1960 . 14. MORROW, A . G. and BROCEENEROUGH, E . C. Surgical treatment of idiopathic hypertrophic subaortic steams : technique and hemodynamic results of subaortic ventriculomyotomy . Ann . Surg ., 154 : 181, 1961 . 15 . DUBILIER, W., TAYLOR, T. C. and STEINBERG, 1 . Aortic sinus aneurysm associated with coarctation of the aorta. Am . J. Roentgenol., 73 : 10, 1955. 16 . LEIDER, H . J, and STEINBERG, L. Subsidence of dilatation of ascending aorta and aortic sinus after resection of coarctation. Report of a case . J. Thoracic & Cardiornsc . Surg ., 41 : 670, 1961 .

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