Considerations in the Surgical Management of Infantile Coarctation of Aorta
JOHN P. CONNORS, MD ALEXIS F. HARTMANN, Jr., MD, FACC CLARENCE S. WELDON, MD, FACC St. Louis, Missouri
From the Divisions of Cardiothoracic Surgery and Pediatric Cardiology, Washington University School of Medicine, St. Louis, Mo. Manuscript accepted March 19, 1975. Address for reprints: John P. Connors, MD, Washington University School of Medicine, Division of Cardiothoracic Surgery, 216 S. Kingshighway, St. Louis, Mo: 63110.
The results of a recent 5 year experience with resection of coarctation of the aorta in infants less than 1 year of age are compared ~vith those of an earlier series from the same institution. The significant improvement in mortality and morbidity statistics is attributed to modifications in operative and postoperative care. Operative mortality has decreased from 38 to 17 percent and the incidence rate of significant restenosis has diminished from 60 to 33 percent. It is suggested that in patients with a large associated intracardiac shunt banding of the main pulmonary artery should be performed before resection of the coarctation. Three of five patients have survived procedures performed in this sequence. Microsurgical techniques and careful approximation of the aortic lumen with interrupted sutures are the major factors responsible for the reduced incidence of recoarctation. Prolonged venUlatory support postoperatively with the occasional addition of controlled positive airway pressure and continued aggressive medical therapy for heart failure are recommended.
Surgical resection of coarctation of the aorta in infants less than 1 year of age remains a challenging endeavor. Nevertheless, there is general agreement that children with uncontrolled congestive heart failure despite aggressive medical management should undergo coarctectomy. 1-5 Factors that unfavorably influence the results in these infants include the degree of left ventricular failure and the presence of severe intracardiac and extracardiac vascular anomalies. It is well established therefore that preparation for resection should include aggressive therapy with digitalis and diuretic agents along with cardiac catheterization and accurate assessment of the associated anomalies. Acceptable mortality figures have ranged between 25 and 45 percent. 1,4,6s The operative mortality rate in the initial series of Patients from this institution was 36 percent (Table I). This report describes the improved results achieved in the last 5 years and attempts to define responsible modifications in the operative and postoperative care of these children. Large cardiac shunts at the ventricular level are among the more common lesions associated with infantile coarctation, and banding of the main pulmonary artery should be carried out at the time of resection. 4,9,1° However, with the initial excision of the coarctation, clamping of the aorta will ~ncrease the impedance to aortic flow which, in the absence of an intraventricular gradient, will increase pulmonary blood flow and, hence, left ventricular diastolic filling. Thus, an excessively afterloaded left ventricle becomes also excessively volume loaded and the result may be acute intraoperative left ventricular failure. We therefore contend that the band should be applied before coarctectomy. The maintenance of aggressive medical therapy and strict attention to ventilatory support in the postoperative period are suggested as further reasons for the improvement in survival rates. The development of stenosis at the site of resection, recreating the
October 6, 1975
The American Journal of CARDIOLOGY
Volume 36
489
E7 AL: pathophysiologic features of coarctation, probably occurs as a consequence of several factors. 11-14 Our recent adaptation of microsurgical techniques similar to those utilized in coronary arterial surgery has significantly diminished the frequency of this complication. With the development of hemodynamically significant stenosis after resection, all patients have remained asymptomatic with medical therapy. The management of recurrent coarctation is safe and effective, and therefore apprehension concerning this complication should not delay the initial procedure in these young children. 11
TABLE I Results of Surgical Resection for Coarctation of Aorta ( 1 9 6 0 - 6 6 and 1969--74)
Patients (no.) Age range tncidence of associated cardiac malformations Incidence of pulmonary arterial banding in association with coarctectomy Early mortality Late mortality
1960-66
1969--74
14 2 days to 11 months 12 of 14 (86%}
18 2 days to 1 year 16 o f 18 (89%)
0 of 14 (0%)
5 of 18 (28%)
4 of 14 (29%) I of 14 (7%)
2 of 18 (12%) 1 of 18 (5%)
Surgical Methods Operative procedures: The coarcted segment was exposed through a left posterior thoracotomy. The third interspace was entered. The pleura overlying the distal arch and proximal descending aorta was incised longitudinally with reflection medially and laterally. The left subclavian artery, distal arch and descending thoracic aorta proximal and distal to the coarctation were looped with tapes. Care was taken to preserve all distal collateral vessels. If catheterization data revealed a large intracardiac shunt with equal systemic and pulmonary arterial pressures, a banding procedure on the main pulmonary artery was performed. The pericardium was opened longitudinally anterior to the left phrenic nerve and the band applied until there was a sustained increase in aortic pressure. A patent ductus arteriosus or ligament was triply ligated. Small coarctation clamps were applied and the involved segment excised. An end to end anastomosis was accomplished in all cases. Frequently the proximal lumen included the origin of the left subclavian artery so that the two aortic ends were nearly equal in size. The anastomoses were carried out with 7-0 and 8-0 suture material in interrupted fashion. Postoperative management: This involved careful attention to ventilatory support as well as continued aggressive therapy of the congestive heart failure. Often these children received respiratory support for 24 to 72 hours, with frequent monitoring of their arterial blood gases. When pulmonary congestion and associated pneumonia developed, controlled positive airway pressure was added to the ventilatory support regimen to improve arterial oxygen saturation. All patients received postoperative antibiotic therapy, usually ampicillin, 11 mg/kg body weight, and kanamycin, 15 mg/kg intramuscularly in divided doses.
Results During the past 5 years, 18 children less than 1 year of age with coarctation of the aorta and associated heart failure were operated upon (Table II). Nine patients were less than 2 weeks of age and the smallest child weighed 1,100 g. Sixteen patients (89 percent) had severe additional intracardiac and extracardiac vascular anomalies, with five patients (28 percent) requiring pulmonary arterial banding at the time of resection (Table I). Mortality: There were no intraoperative deaths. Two early deaths (Cases 1 and 6) occurred at 12 and 14 hours postoperatively. Both infants died with profound cardiac failure. One patient had corrected transposition of the great vessels with atrioventricular communis and underwent banding at the time of
490
October 6, 1975
The American Journal of CARDIOLOGY
resection. T he second child had aortic valvular stenosis and an atretic aortic arch. A late death occurred 31 days postoperatively in a patient (Case 8) with a secundum atrial septal defect, large ventricular septal defect and hypoplastic left ventricle. This patient also had a pulmonary arterial banding as well. T h e other children who underwent pulmonary arterial banding in association with coarctectomy survived (Table II). Follow-up: Information is available on all 15 survival patients (Table III). The majority have had Doppler blood pressure measurements. Five patients (36 percent) have a significant gradient of 20 mm Hg or more between the upper and lower limbs. Only one patient (Case 2) has significant hypertension in the arms, but she remains asymptomatic with medical therapy.
Comments Infants with coarctation of the aorta and congestive heart failure present challenging problems to all involved in their care. More than 75 percent of these children have severe associated cardiac or great vessel anomalies which by reason of shunt or obstructive phenomena place added strain upon the left ventricle. 7,9,15,19 Among the most common abnormal cardiac communications are ventricular septal defect and persistent common atrioventricular (A-V) canal. Becker et al. 9 reported that 36 percent of their cases had these lesions. Tubular hypoplasia of the aorta, underdevelopment of the left heart chambers and obstructive lesions involving the mitral valve and left ventricular outflow tract are often described. Endocardial fibroelastosis is frequently associated with and considered to be secondary to coarctation of the aorta, severe aortic stenosis or aortic atresia. TM When these severe anomalies are present attempts at medical management alone are understandably disastrous, and, indeed, surgical intervention is often futile. There is little doubt that the more advanced the anomaly, the worse the prognosis, whatever the t r e a t m e n t regimen. The mortality rate associated with surgical resection has ranged between 25 and 45 percent. T he results in a group of infants operated upon in an earlier era at our institution were not dissimilar. These figures represent considerable im-
Volume 36
INFANTILE COARCTATION OF AORTA--CONNORS ET AL.
T A B L E II
T A B L E III
Coexisting Cardiac Anomalies and Results of Surgery for Coarctation of Aorta (1969--74)
Follow-Up of Patients (1969--74)
Case Age at no. Operation
Case no.
Age at Resection (too)
Length of Follow-Up (too)
Pressure Gradient Between Upper and Lower Limbs (mm Hg)
2 3 4 5 7 9 10 11 12 13 14 15 16 17 18
3 1 wk 1 wk 2 wk 2 wk 2 wk 3 wk 1 4 12 5 3 3 4 1 wk
2 22 37 37 21 34 36 12 23 37 30 2 2 3 2
None 28 (110/92; 82/60) None 66 (136/104; 70/0) 14 (104/90; 90/40) 44 (126/90; 82/60) 50 (145/90; 95/0) None None 12 (11/84; 98/80) 14 (112/80; 98/84) None None None None
1
2 days
2
3 days
3
5 days
4
7 days
5
9 days
6 10 days
Anatomic Diagnosis
Operation
Coarctation, VSD, Coarctectomy ASD, hypoplasia of ascending aorta Coarctation, PDA Coarctectomy (1,100 g wt) Coarctation, PA banding, ASD, VSD, PDA coarctectomy Coarctation, PA banding, VSD, PDA coarctectomy Coarctation, ASD Coarctectomy Coarctation, corrected TGV, A-V canal Coarctation, PDA
7
2 weeks
8
2 weeks
9
2 weeks
10
3 weeks
Coarctation, ASD, VSD, LV hypoplasia Coarctation, pulmonary hypertension Coarctation VSD
11
1 month
Coarctation, VSD
12
4months Coarctation, EFE
13 14
5 months Coarctation, PDA, EFE 1 year Coarctation EFE
15
1 year
16
3months Coarctation
17
4months Coarctation, EFE
18
7 days
Coarctation, PDA
Coarctation, ASD
Result Early death
Alive and well Alive and well Alive and well Alive and well PA banding, Early coarctectomy death
Coarctectomy PA banding, coarctectomy Coarctectomy
Alive and well Late death Alive and welt
Coarctectomy Alive (1,500 g wt) and well PA banding, Alive coarctectomy and well Coarctectomy Alive and well Coarctectomy Alive and well Coarctectomy Alive and well Coarctectomy Alive and well Coarctectomy Alive and well Coarctectomy Alive and well Coarctectomy Alive and well
ASD = atrial septal defect; A-V = atrioventricular; EFE = endocardial fibroetastosis; LV = left ventricular; PA = pulmonary arterial; PDA = patent ductus arteriosus; TGV = transposition of the great vessels; VSD = ventricular septal defect; wt = weight.
provement over medical therapy alone since most of these ill children die without surgical intervention. Recent modifications in our operative and postoperative technique have contributed to further improvement in the statistics. I n d i c a t i o n s for and timing of p u l m o n a r y arterial banding: Many of these children have a large ventricular septal defect or severe endocardial cushion defect with pulmonary overcirculation and hypertension. Areas of major concern therefore are the indications for and timing of pulmonary arterial banding. Any child with a large intracardiac left to right shunt whose ventricular pressures are equal should undergo coincident banding. This maneuver must precede the resection of the coarctation in order to avoid the acute exacerbation of left ventricular failure due to further volume overload. We disagree with Litwin et al. 1° that "prior aortic resection and anastomosis protects against the possible adverse effects of simultaneously embarrassing both ventri-
cles." On the contrary, it has been our experience t h a t volume overload of the already compromised left ventricle (with the initial resection of the coarctation) has proved consistently detrimental. Five patients in our recent series have had pulmonary arterial banding (Cases 3, 4, 6, 8 and 11, Table II). One (Case 4) died 12 hours postoperatively and was found to have corrected transposition of the great vessels with a complete A-V canal. A second patient (Case 8) died 1 month postoperatively from severe congestive heart failure. Postmortem examination of this patient demonstrated a secundum atrial septal defect, large ventricular septal defect and hypoplasia of the left ventricle. In one patient (Case 10) with a small interventricular gradient (20 mm Hg) a temporary band was placed before coarctectomy and immediately removed after resection. There is currently enthusiasm for the primary repair of congenital heart defects utilizing deep hypothermia techniques, and total correction of a coarctation and ventricular septal defect may be carried out. Again, in the presence of a large shunt, temporary banding of the pulmonary artery should be performed before resection of the coarctation. Indications for surgical resection: Nine children had less significant or no associated malformations. There were no postoperative deaths in this group. Consequently we believe that any child less than 1 year of age with coarctation of the aorta and associated left ventricular failure should have surgical resection. It has been our experience that although some infants manifest improvement in the first 24 to 48 hours of medical therapy, most become even more desperately ill or die suddenly before correction can be performed. Furthermore, persistent hypertension in the arms, multiple hospitalizations, failure to thrive and continued stress upon the left ventricle and arterial system have influenced this decision. We therefore initiate intensive digitalis and diuretic therapy, perform cardiac catheterization, and within 48 hours operate upon all infants with proved coarc-
October 6, 1975
The American Journal of CARDIOLOGY
Volume 36
491
INFANTILE COARCTATION OF AORTA--CONNORS ET AL
ration who have presented with congestive heart failore. Recoarctation: A most important criticism of coarctation resection in infancy is that anastomotic stenosis frequently redevelops. 12-14,16-1s The severity and time sequence for the development of this complication are quite variable. Factors involved in the recreation of the coarctation are probably multiple and include (1) inadequate anastomotic lumen, (2) thrombosis at the anastomotic site, (3) failure of the anastomosis to grow, and (4) retention of abnormal aortic tissues that provide progressive obstruction through the development of proliferative intima or hyperplastic media. Moderate stenosis (gradient between upper and lower limbs of 20 mm Hg or more) may not be associated with hypertension or left ventricular failure. Eight of 20 unselected patients previously reported on were in this category and were followed up. 17 Four additional patients had significant hypertension of the upper limbs and required reoperation. Twelve patients (60 percent) in the earlier series therefore demonstrated some degree of anastomotic stenosis. Simple and safe techniques for the resection of a recurrent coarctation have been developed and the relief of hypertension or pressure gradients between the arms and legs may be reduced or abolished. 11 In the recent group, 5 of 15 children (33 percent) followed up an average of 20.6 months have signifi-
cant blood pressure gradients. Only one child (Case 2) has severe hypertension. She weighed 1,100 g at the time of resection and showed evidence of recurrent coarctation 2 weeks postoperatively. This patient has been followed up for 22 months and is doing well on medical therapy. The four other children have gradients greater than 20 mm Hgl but none is severely hypertensive. The reduction in the incidence of recoarctation may be attributed to modifications in surgical technique. All involved tissue must be removed and the approximated lumens should be of near equal caliber. This often requires that the proximal portion of the left subclavian artery be utilized in the creation of a proximal lumen. The suture material used should be fine, that is 7-0 or 8-0 in size, and placed in interrupted fashion through the entire anastomosis. P o s t o p e r a t i v e m a n a g e m e n t : Since many of these patients have profound heart failure preoperatively we have been most attentive to ventilatory support in the postoperative period. Arterial blood gases are monitored closely and, with the development of pulmonary edema, atelectasis or pneumonia, arterial oxygen saturation may be maintained with the use of controlled positive airway pressure. Antibiotic therapy and frequent suctioning are utilized to control pneumonic infiltrates, and endotracheal tubes are often left for 24 to 72 hours. Aggressive digitalis and diuretic therapy is continued as preoperatively.
References 1. Glass IH, Mustard WT, Keith JS: Coarctation of the aorta in infants. Pediatrics 26:109-121, 1960 2. Campbell M, Bayles JH: The course and prognosis of coarctation of the aorta. Br Heart J 18:475-495, 1956 3. Burford TH, Ferguson TB, Goldring D, et ah Coarctation of the aorta in infants: a clinical and experimental study. J Thorac Cardiovasc Surg 39:47-59, 1960 4. Waldhausen JA, King H, Nahrwold DL, et al: Management of coarctation in infancy. JAMA 187:116-121, 1964 5. Mortensen JD, Cutler PR, Rumel WR, el ah Management of coarctation of the aorta in infancy. J Thorac Cardiovasc Surg 37:502-509, 1959 6. Cooley DA, Hallman GL: Surgery during the first year of life for cardiovascular anomalies. A review of 500 consecutive operations. Am J Surg 107:584-590, 1964 7. Hartmann AF, Goldring D, Staple TW: Coarctation of the aorta in infancy. Hemodynamic studies. J Pediatr 70:95-104, 1967 8. Freundlch E, Engle MA, Goldberg HP: Coarctation of the aorta in infancy. Pediatrics 27:427-439, 1961 9. Becker AE, Mies BJ, Edwards JE: Anomalies associated with coarctation of the aorta, particular reference to infancy. Circulation 41:1067-1075, 1970 10. Litwin SB, Bernhard WF, Rosenthal A, et ah Surgical resection of coarctation of the aorta in infancy. J Pediatr Surg 6:307-313, 1971
492
October 6, 1975
The American Journal of CARDIOLOGY
11. Weldon CS, Hartmann AF, Steinhoff NG, et al: A simple, safe and rapid technique for the management of recurrent coarctation of the aorta. Ann Thorac Surg 15:510-519, 1973 12. Parsons CG, Astley R: Recurrence of aortic coarctation after operation in childhood. Br Meal J 1:573-577, 1966 13. Mulder DG, Linde LM: Recurrent coarctation of the aorta in infancy. Arn Surg 25:908-911, 1959 14. Khoury GH, Hawes CK: Recurrent coarctation of the aorta in infancy and childhood. J Pediatr 72:801-806, 1968 15. Tawes RL, Aberdeen E, Waterston DJ, et ah Coarctation of the aorta in infants and children. Circulation 39, 40:Suppl I: 1-173-1184, 1969 16. Anderson DH, Kelly J: Endocardial fibroelastosis: I. Endocardial fibroelastosis associated with congenital malformation of the heart. II. A clinical and pathologic investigation of those cases without associated cardiac malformations, including report of two familial instances. Pediatrics 18:513-555, 1956 17. Hartmann AF, Goldring D, Hernandez A, et al: Recurrent coarctation of the aorta after successful repair in infancy. Am J Cardiol 25:405-410, 1970 18. Gross RE: Surgery for coarctation of the aorta in infants. Am J Cardiol 25:507-508, 1970 19. Maim JR, Blumenthal S, Jameson AG, et ah Observations on coarctation of the aorta in infants. Arch Surg 86:110-117, 1962
Volume 36
JOHN P. CONNORS, MD ALEXIS F. HARTMANN, Jr., MD, FACC CLARENCE S. WELDON, MD, FACC St. Louis, Missouri
From the Divisions of Cardiothoracic Surgery and Pediatric Cardiology, Washington University School of Medicine, St. Louis, Mo. Manuscript accepted March 19, 1975. Address for reprints: John P. Connors, MD, Washington University School of Medicine, Division of Cardiothoracic Surgery, 216 S. Kingshighway, St. Louis, Mo: 63110.
The results of a recent 5 year experience with resection of coarctation of the aorta in infants less than 1 year of age are compared ~vith those of an earlier series from the same institution. The significant improvement in mortality and morbidity statistics is attributed to modifications in operative and postoperative care. Operative mortality has decreased from 38 to 17 percent and the incidence rate of significant restenosis has diminished from 60 to 33 percent. It is suggested that in patients with a large associated intracardiac shunt banding of the main pulmonary artery should be performed before resection of the coarctation. Three of five patients have survived procedures performed in this sequence. Microsurgical techniques and careful approximation of the aortic lumen with interrupted sutures are the major factors responsible for the reduced incidence of recoarctation. Prolonged venUlatory support postoperatively with the occasional addition of controlled positive airway pressure and continued aggressive medical therapy for heart failure are recommended.
Surgical resection of coarctation of the aorta in infants less than 1 year of age remains a challenging endeavor. Nevertheless, there is general agreement that children with uncontrolled congestive heart failure despite aggressive medical management should undergo coarctectomy. 1-5 Factors that unfavorably influence the results in these infants include the degree of left ventricular failure and the presence of severe intracardiac and extracardiac vascular anomalies. It is well established therefore that preparation for resection should include aggressive therapy with digitalis and diuretic agents along with cardiac catheterization and accurate assessment of the associated anomalies. Acceptable mortality figures have ranged between 25 and 45 percent. 1,4,6s The operative mortality rate in the initial series of Patients from this institution was 36 percent (Table I). This report describes the improved results achieved in the last 5 years and attempts to define responsible modifications in the operative and postoperative care of these children. Large cardiac shunts at the ventricular level are among the more common lesions associated with infantile coarctation, and banding of the main pulmonary artery should be carried out at the time of resection. 4,9,1° However, with the initial excision of the coarctation, clamping of the aorta will ~ncrease the impedance to aortic flow which, in the absence of an intraventricular gradient, will increase pulmonary blood flow and, hence, left ventricular diastolic filling. Thus, an excessively afterloaded left ventricle becomes also excessively volume loaded and the result may be acute intraoperative left ventricular failure. We therefore contend that the band should be applied before coarctectomy. The maintenance of aggressive medical therapy and strict attention to ventilatory support in the postoperative period are suggested as further reasons for the improvement in survival rates. The development of stenosis at the site of resection, recreating the
October 6, 1975
The American Journal of CARDIOLOGY
Volume 36
489
E7 AL: pathophysiologic features of coarctation, probably occurs as a consequence of several factors. 11-14 Our recent adaptation of microsurgical techniques similar to those utilized in coronary arterial surgery has significantly diminished the frequency of this complication. With the development of hemodynamically significant stenosis after resection, all patients have remained asymptomatic with medical therapy. The management of recurrent coarctation is safe and effective, and therefore apprehension concerning this complication should not delay the initial procedure in these young children. 11
TABLE I Results of Surgical Resection for Coarctation of Aorta ( 1 9 6 0 - 6 6 and 1969--74)
Patients (no.) Age range tncidence of associated cardiac malformations Incidence of pulmonary arterial banding in association with coarctectomy Early mortality Late mortality
1960-66
1969--74
14 2 days to 11 months 12 of 14 (86%}
18 2 days to 1 year 16 o f 18 (89%)
0 of 14 (0%)
5 of 18 (28%)
4 of 14 (29%) I of 14 (7%)
2 of 18 (12%) 1 of 18 (5%)
Surgical Methods Operative procedures: The coarcted segment was exposed through a left posterior thoracotomy. The third interspace was entered. The pleura overlying the distal arch and proximal descending aorta was incised longitudinally with reflection medially and laterally. The left subclavian artery, distal arch and descending thoracic aorta proximal and distal to the coarctation were looped with tapes. Care was taken to preserve all distal collateral vessels. If catheterization data revealed a large intracardiac shunt with equal systemic and pulmonary arterial pressures, a banding procedure on the main pulmonary artery was performed. The pericardium was opened longitudinally anterior to the left phrenic nerve and the band applied until there was a sustained increase in aortic pressure. A patent ductus arteriosus or ligament was triply ligated. Small coarctation clamps were applied and the involved segment excised. An end to end anastomosis was accomplished in all cases. Frequently the proximal lumen included the origin of the left subclavian artery so that the two aortic ends were nearly equal in size. The anastomoses were carried out with 7-0 and 8-0 suture material in interrupted fashion. Postoperative management: This involved careful attention to ventilatory support as well as continued aggressive therapy of the congestive heart failure. Often these children received respiratory support for 24 to 72 hours, with frequent monitoring of their arterial blood gases. When pulmonary congestion and associated pneumonia developed, controlled positive airway pressure was added to the ventilatory support regimen to improve arterial oxygen saturation. All patients received postoperative antibiotic therapy, usually ampicillin, 11 mg/kg body weight, and kanamycin, 15 mg/kg intramuscularly in divided doses.
Results During the past 5 years, 18 children less than 1 year of age with coarctation of the aorta and associated heart failure were operated upon (Table II). Nine patients were less than 2 weeks of age and the smallest child weighed 1,100 g. Sixteen patients (89 percent) had severe additional intracardiac and extracardiac vascular anomalies, with five patients (28 percent) requiring pulmonary arterial banding at the time of resection (Table I). Mortality: There were no intraoperative deaths. Two early deaths (Cases 1 and 6) occurred at 12 and 14 hours postoperatively. Both infants died with profound cardiac failure. One patient had corrected transposition of the great vessels with atrioventricular communis and underwent banding at the time of
490
October 6, 1975
The American Journal of CARDIOLOGY
resection. T he second child had aortic valvular stenosis and an atretic aortic arch. A late death occurred 31 days postoperatively in a patient (Case 8) with a secundum atrial septal defect, large ventricular septal defect and hypoplastic left ventricle. This patient also had a pulmonary arterial banding as well. T h e other children who underwent pulmonary arterial banding in association with coarctectomy survived (Table II). Follow-up: Information is available on all 15 survival patients (Table III). The majority have had Doppler blood pressure measurements. Five patients (36 percent) have a significant gradient of 20 mm Hg or more between the upper and lower limbs. Only one patient (Case 2) has significant hypertension in the arms, but she remains asymptomatic with medical therapy.
Comments Infants with coarctation of the aorta and congestive heart failure present challenging problems to all involved in their care. More than 75 percent of these children have severe associated cardiac or great vessel anomalies which by reason of shunt or obstructive phenomena place added strain upon the left ventricle. 7,9,15,19 Among the most common abnormal cardiac communications are ventricular septal defect and persistent common atrioventricular (A-V) canal. Becker et al. 9 reported that 36 percent of their cases had these lesions. Tubular hypoplasia of the aorta, underdevelopment of the left heart chambers and obstructive lesions involving the mitral valve and left ventricular outflow tract are often described. Endocardial fibroelastosis is frequently associated with and considered to be secondary to coarctation of the aorta, severe aortic stenosis or aortic atresia. TM When these severe anomalies are present attempts at medical management alone are understandably disastrous, and, indeed, surgical intervention is often futile. There is little doubt that the more advanced the anomaly, the worse the prognosis, whatever the t r e a t m e n t regimen. The mortality rate associated with surgical resection has ranged between 25 and 45 percent. T he results in a group of infants operated upon in an earlier era at our institution were not dissimilar. These figures represent considerable im-
Volume 36
INFANTILE COARCTATION OF AORTA--CONNORS ET AL.
T A B L E II
T A B L E III
Coexisting Cardiac Anomalies and Results of Surgery for Coarctation of Aorta (1969--74)
Follow-Up of Patients (1969--74)
Case Age at no. Operation
Case no.
Age at Resection (too)
Length of Follow-Up (too)
Pressure Gradient Between Upper and Lower Limbs (mm Hg)
2 3 4 5 7 9 10 11 12 13 14 15 16 17 18
3 1 wk 1 wk 2 wk 2 wk 2 wk 3 wk 1 4 12 5 3 3 4 1 wk
2 22 37 37 21 34 36 12 23 37 30 2 2 3 2
None 28 (110/92; 82/60) None 66 (136/104; 70/0) 14 (104/90; 90/40) 44 (126/90; 82/60) 50 (145/90; 95/0) None None 12 (11/84; 98/80) 14 (112/80; 98/84) None None None None
1
2 days
2
3 days
3
5 days
4
7 days
5
9 days
6 10 days
Anatomic Diagnosis
Operation
Coarctation, VSD, Coarctectomy ASD, hypoplasia of ascending aorta Coarctation, PDA Coarctectomy (1,100 g wt) Coarctation, PA banding, ASD, VSD, PDA coarctectomy Coarctation, PA banding, VSD, PDA coarctectomy Coarctation, ASD Coarctectomy Coarctation, corrected TGV, A-V canal Coarctation, PDA
7
2 weeks
8
2 weeks
9
2 weeks
10
3 weeks
Coarctation, ASD, VSD, LV hypoplasia Coarctation, pulmonary hypertension Coarctation VSD
11
1 month
Coarctation, VSD
12
4months Coarctation, EFE
13 14
5 months Coarctation, PDA, EFE 1 year Coarctation EFE
15
1 year
16
3months Coarctation
17
4months Coarctation, EFE
18
7 days
Coarctation, PDA
Coarctation, ASD
Result Early death
Alive and well Alive and well Alive and well Alive and well PA banding, Early coarctectomy death
Coarctectomy PA banding, coarctectomy Coarctectomy
Alive and well Late death Alive and welt
Coarctectomy Alive (1,500 g wt) and well PA banding, Alive coarctectomy and well Coarctectomy Alive and well Coarctectomy Alive and well Coarctectomy Alive and well Coarctectomy Alive and well Coarctectomy Alive and well Coarctectomy Alive and well Coarctectomy Alive and well
ASD = atrial septal defect; A-V = atrioventricular; EFE = endocardial fibroetastosis; LV = left ventricular; PA = pulmonary arterial; PDA = patent ductus arteriosus; TGV = transposition of the great vessels; VSD = ventricular septal defect; wt = weight.
provement over medical therapy alone since most of these ill children die without surgical intervention. Recent modifications in our operative and postoperative technique have contributed to further improvement in the statistics. I n d i c a t i o n s for and timing of p u l m o n a r y arterial banding: Many of these children have a large ventricular septal defect or severe endocardial cushion defect with pulmonary overcirculation and hypertension. Areas of major concern therefore are the indications for and timing of pulmonary arterial banding. Any child with a large intracardiac left to right shunt whose ventricular pressures are equal should undergo coincident banding. This maneuver must precede the resection of the coarctation in order to avoid the acute exacerbation of left ventricular failure due to further volume overload. We disagree with Litwin et al. 1° that "prior aortic resection and anastomosis protects against the possible adverse effects of simultaneously embarrassing both ventri-
cles." On the contrary, it has been our experience t h a t volume overload of the already compromised left ventricle (with the initial resection of the coarctation) has proved consistently detrimental. Five patients in our recent series have had pulmonary arterial banding (Cases 3, 4, 6, 8 and 11, Table II). One (Case 4) died 12 hours postoperatively and was found to have corrected transposition of the great vessels with a complete A-V canal. A second patient (Case 8) died 1 month postoperatively from severe congestive heart failure. Postmortem examination of this patient demonstrated a secundum atrial septal defect, large ventricular septal defect and hypoplasia of the left ventricle. In one patient (Case 10) with a small interventricular gradient (20 mm Hg) a temporary band was placed before coarctectomy and immediately removed after resection. There is currently enthusiasm for the primary repair of congenital heart defects utilizing deep hypothermia techniques, and total correction of a coarctation and ventricular septal defect may be carried out. Again, in the presence of a large shunt, temporary banding of the pulmonary artery should be performed before resection of the coarctation. Indications for surgical resection: Nine children had less significant or no associated malformations. There were no postoperative deaths in this group. Consequently we believe that any child less than 1 year of age with coarctation of the aorta and associated left ventricular failure should have surgical resection. It has been our experience that although some infants manifest improvement in the first 24 to 48 hours of medical therapy, most become even more desperately ill or die suddenly before correction can be performed. Furthermore, persistent hypertension in the arms, multiple hospitalizations, failure to thrive and continued stress upon the left ventricle and arterial system have influenced this decision. We therefore initiate intensive digitalis and diuretic therapy, perform cardiac catheterization, and within 48 hours operate upon all infants with proved coarc-
October 6, 1975
The American Journal of CARDIOLOGY
Volume 36
491
INFANTILE COARCTATION OF AORTA--CONNORS ET AL
ration who have presented with congestive heart failore. Recoarctation: A most important criticism of coarctation resection in infancy is that anastomotic stenosis frequently redevelops. 12-14,16-1s The severity and time sequence for the development of this complication are quite variable. Factors involved in the recreation of the coarctation are probably multiple and include (1) inadequate anastomotic lumen, (2) thrombosis at the anastomotic site, (3) failure of the anastomosis to grow, and (4) retention of abnormal aortic tissues that provide progressive obstruction through the development of proliferative intima or hyperplastic media. Moderate stenosis (gradient between upper and lower limbs of 20 mm Hg or more) may not be associated with hypertension or left ventricular failure. Eight of 20 unselected patients previously reported on were in this category and were followed up. 17 Four additional patients had significant hypertension of the upper limbs and required reoperation. Twelve patients (60 percent) in the earlier series therefore demonstrated some degree of anastomotic stenosis. Simple and safe techniques for the resection of a recurrent coarctation have been developed and the relief of hypertension or pressure gradients between the arms and legs may be reduced or abolished. 11 In the recent group, 5 of 15 children (33 percent) followed up an average of 20.6 months have signifi-
cant blood pressure gradients. Only one child (Case 2) has severe hypertension. She weighed 1,100 g at the time of resection and showed evidence of recurrent coarctation 2 weeks postoperatively. This patient has been followed up for 22 months and is doing well on medical therapy. The four other children have gradients greater than 20 mm Hgl but none is severely hypertensive. The reduction in the incidence of recoarctation may be attributed to modifications in surgical technique. All involved tissue must be removed and the approximated lumens should be of near equal caliber. This often requires that the proximal portion of the left subclavian artery be utilized in the creation of a proximal lumen. The suture material used should be fine, that is 7-0 or 8-0 in size, and placed in interrupted fashion through the entire anastomosis. P o s t o p e r a t i v e m a n a g e m e n t : Since many of these patients have profound heart failure preoperatively we have been most attentive to ventilatory support in the postoperative period. Arterial blood gases are monitored closely and, with the development of pulmonary edema, atelectasis or pneumonia, arterial oxygen saturation may be maintained with the use of controlled positive airway pressure. Antibiotic therapy and frequent suctioning are utilized to control pneumonic infiltrates, and endotracheal tubes are often left for 24 to 72 hours. Aggressive digitalis and diuretic therapy is continued as preoperatively.
References 1. Glass IH, Mustard WT, Keith JS: Coarctation of the aorta in infants. Pediatrics 26:109-121, 1960 2. Campbell M, Bayles JH: The course and prognosis of coarctation of the aorta. Br Heart J 18:475-495, 1956 3. Burford TH, Ferguson TB, Goldring D, et ah Coarctation of the aorta in infants: a clinical and experimental study. J Thorac Cardiovasc Surg 39:47-59, 1960 4. Waldhausen JA, King H, Nahrwold DL, et al: Management of coarctation in infancy. JAMA 187:116-121, 1964 5. Mortensen JD, Cutler PR, Rumel WR, el ah Management of coarctation of the aorta in infancy. J Thorac Cardiovasc Surg 37:502-509, 1959 6. Cooley DA, Hallman GL: Surgery during the first year of life for cardiovascular anomalies. A review of 500 consecutive operations. Am J Surg 107:584-590, 1964 7. Hartmann AF, Goldring D, Staple TW: Coarctation of the aorta in infancy. Hemodynamic studies. J Pediatr 70:95-104, 1967 8. Freundlch E, Engle MA, Goldberg HP: Coarctation of the aorta in infancy. Pediatrics 27:427-439, 1961 9. Becker AE, Mies BJ, Edwards JE: Anomalies associated with coarctation of the aorta, particular reference to infancy. Circulation 41:1067-1075, 1970 10. Litwin SB, Bernhard WF, Rosenthal A, et ah Surgical resection of coarctation of the aorta in infancy. J Pediatr Surg 6:307-313, 1971
492
October 6, 1975
The American Journal of CARDIOLOGY
11. Weldon CS, Hartmann AF, Steinhoff NG, et al: A simple, safe and rapid technique for the management of recurrent coarctation of the aorta. Ann Thorac Surg 15:510-519, 1973 12. Parsons CG, Astley R: Recurrence of aortic coarctation after operation in childhood. Br Meal J 1:573-577, 1966 13. Mulder DG, Linde LM: Recurrent coarctation of the aorta in infancy. Arn Surg 25:908-911, 1959 14. Khoury GH, Hawes CK: Recurrent coarctation of the aorta in infancy and childhood. J Pediatr 72:801-806, 1968 15. Tawes RL, Aberdeen E, Waterston DJ, et ah Coarctation of the aorta in infants and children. Circulation 39, 40:Suppl I: 1-173-1184, 1969 16. Anderson DH, Kelly J: Endocardial fibroelastosis: I. Endocardial fibroelastosis associated with congenital malformation of the heart. II. A clinical and pathologic investigation of those cases without associated cardiac malformations, including report of two familial instances. Pediatrics 18:513-555, 1956 17. Hartmann AF, Goldring D, Hernandez A, et al: Recurrent coarctation of the aorta after successful repair in infancy. Am J Cardiol 25:405-410, 1970 18. Gross RE: Surgery for coarctation of the aorta in infants. Am J Cardiol 25:507-508, 1970 19. Maim JR, Blumenthal S, Jameson AG, et ah Observations on coarctation of the aorta in infants. Arch Surg 86:110-117, 1962
Volume 36
