BLALOCK-TAUSSIG ANASTOMOSIS FOR TETRALOGY OF FALLOT. A TEN-TO-FIFTEEN YEAR FOLLOW-UP

Left arm structure and function late after subclavian flap repair of aortic coarctation in childhood

OBJECTIVES

Concerns exist over the long-term consequences of subclavian artery ligation in subclavian flap repair for coarctation of the aorta. We sought to analyse upper limb structural and functional performance in adults who have had surgery in childhood for coarctation of the aorta, using either subclavian flap repair or end to end aortic anastomosis.

METHODS

Two-group observational design using anatomical and upper limb functional performance measures. Purposive sampling from our specialist adult congenital heart disease database of patients who received subclavian flap repair or end to end anastomosis for coarctation of the aorta as children. Upper limb measurements were completed using MRI and blood flow velocity with ultrasound imaging. Bilateral standardised upper limb functional testing of assessment of strength, dexterity and a standardised self-report of upper limb disability was completed.

RESULTS

Eighteen right-handed patients, 9 with subclavian repair, (38 ± 12 years, 78% males) were studied. Age at repair was 4.7 ± 5.9 years; mean time from initial repair 32 ± 9 years. The subclavian group had a larger difference between right and left when compared the end to end anastomosis group in: lower arm muscle mass (94.5 ± 42.3 mls versus 37.8 ± 94.5 mls, p = 0.008), lower arm maximal cross-sectional area, (5.9 ± 2.8 cm2 versus 2.9 ± 2.6 cm2, p = 0.038) and grip strength (14.7 ± 8.3 lbs versus 5.9 ± 5.3 lbs, p = 0.016) There were no significant functional differences between groups.

CONCLUSIONS

In adults with repaired coarctation of the aorta, those with subclavian flap repair had a greater right to left arm muscle mass and grip strength differential when compared to those with end to end anastomosis repair.

Reduced Handgrip Strength in Congenital Heart Disease With Regard to the Shunt Procedure in Infancy

Objective: In many patients with congenital heart disease (CHD) arterial blood flow to the arms is inhibited due to shunt surgery in infancy. This study investigates the handgrip strength of patients with CHD in regard to previous shunt procedures. Patients and Methods: Handgrip was evaluated in 424 patients with various CHD (189 female, age 28.1 ± 13.4 years) including 63 with shunt procedures in infancy; and 123 controls (51 female, 35.6 ± 14.2 years) using a Jamar dynamometer adjusted for hand size. The best of three repetitions was recorded for each side and the right-to-left hand ratio was calculated. The 63 shunted patients were grouped considering the side of the shunt: 14 right, 35 central and 14 left. Results: Patients with CHD, especially shunts, had significantly lower handgrip strength in the dominant hand than controls (controls: 43.2 ± 14.8 kg, CHD: 36.8 ± 14.8 kg, left shunt: 33.6 ± 14.6 kg, central shunt: 30.7 ± 15.2 kg and right shunt 27.8 ± 13.6 kg; p < 0.001). In controls the right hand was 8.3% stronger, comparable to patients with either no shunt or central shunt (controls: 8.3 ± 13.2%; no shunt: 7.9 ± 15.3%; central shunt: 9.5 ± 18.1% p = 0.820). In patients with a left shunt the right hand was 22.5 ± 17.8% stronger than the left (p = 0.027 compared to central) while in those with a right shunt the right hand was 2.3 ± 18.3% weaker (p = 0.049 compared to central). Conclusions: Shunt procedures in infancy cause reduced handgrip strength in adulthood and diminished handgrip strength of the ipsilateral site.

Impaired arm development after Blalock-Taussig shunts in adults with repaired tetralogy of Fallot

BACKGROUND

Many adults with repaired tetralogy of Fallot have had prior Blalock-Taussig shunts. These shunts may theoretically hinder growth and development of the ipsilateral arm.

METHODS

We prospectively enrolled consecutive patients with tetralogy of Fallot in a cross-sectional study to measure arm length and assess handgrip strength. Bilateral handgrip strength was quantified by a dynamometer in a standing position after instructing patients to clench each hand tightly in succession. The maximum force achieved, in kilograms, was measured.

RESULTS

A total of 80 consecutive adults with tetralogy of Fallot, aged 36.0 ± 12.5 years, 49% female, were prospectively enrolled. Thirty-eight (47.5%) patients had prior Blalock-Taussig shunts at a median age of 1.0 year. Twenty-one (55.3%) were left-sided and 23 (60.5%) were classic shunts. All but six patients with right-sided shunts and one without a prior shunt were right-handed. The shunts were present for a median of 4.0 years prior to takedown during corrective surgery. The arm ipsilateral to the shunt was significantly shorter than the contralateral arm (71.5 ± 6.1 versus 73.6 ± 5.6 cm, P<0.0001). Handgrip strength was significantly weaker on the ipsilateral versus contralateral side (median [IQR], 26.5 [14.0-41.5] versus 31.0 [18.0-46.0] kg, P<0.0001) and the ipsilateral-to-contralateral handgrip ratio was lower with classic versus modified shunts (median [IQR], 1.05 [1.02-1.14] versus 1.19 [1.07-1.33] kg, P=0.0541).

CONCLUSION

In patients with tetralogy of Fallot, Blalock-Taussig shunts may impair normal development of the ipsilateral arm with repercussions in adulthood that include shorter limb length and reduced handgrip strength. These changes are most pronounced in patients with classic end-to-side anastomoses.

Evaluation of superficial femoral artery compromise and limb growth retardation after transfemoral artery balloon dilatations

BACKGROUND

Abnormalities of arterial pulse and limb growth after retrograde femoral arterial catheterization have been well documented. However, the magnitude of such complications after transfemoral artery balloon dilatation has not been thoroughly investigated. This study sought to evaluate the prevalence of these abnormalities in children who have undergone transfemoral artery balloon dilatation.

METHODS AND RESULTS

Data on 43 consecutive patients (1 day to 15.5 years old at the time of balloon dilatation) seen on follow-up (42 +/- 23 months) (group 1) were compared with those of 35 patients undergoing retrograde femoral arterial catheterization (group 2) and 47 control patients. Interventional ankle/control ankle blood pressure index (AAI), ratio of interventional/control lower limb length (LLI), and leg length difference (LLD) were measured. Ages and weights at study were similar in all three groups, as were the ages and weights at intervention and duration of follow-up in groups 1 and 2. The AAI was lower (P = .023) in group 1 (0.95 +/- 0.13) than in groups 2 (1.0 +/- 0.1) and 3 (1.01 +/- 0.09). The prevalence of subjects with AAI < or = 0.9 was higher (P = .003) in group 1 than in the other two groups. The LLI and LLD were similar (P > .1) in all three groups. AAI and LLD in the balloon group are not significantly associated with age and weight at intervention, duration of follow-up, or size of the balloon or balloon catheter shaft.

CONCLUSIONS

Transfemoral artery balloon dilatation procedures produce superficial femoral artery compromise, but there was no significant limb growth retardation at a 3.5-year mean follow-up, which may be related to development of collateral circulation. Study of a larger number of children at a longer follow-up interval may be necessary to further confirm these observations.

Does an aortopulmonary shunt before repair of tetralogy of Fallot limit exercise tolerance in long-term survivors?

The purpose of this study was to evaluate the impact of an aortopulmonary shunt on exercise capacity in long-term survivors after total repair of tetralogy of Fallot (17.6(2.0) years' follow-up). Submaximal exercise tests, pulmonary function tests, lund diffusion tests for carbon monoxide, two-dimensional and Doppler echocardiography were performed in 12 patients with an aortopulmonary shunt (group A) and in 21 patients (group B) without a shunt before repair. There were no significant differences in two-dimensional and Doppler echocardiographic findings nor in pulmonary function. Group A showed a significantly lower diffusion capacity of the lung for carbon monoxide at rest (66.2(13.0)% versus 84.1(9.5)%; P < 0.01) and at the anaerobic threshold (71.8(11.0)% versus 87.2(9.8)%; P < 0.01) as well as a significantly reduced physical working capacity at ventilatory anaerobic threshold (1.6)(0.32) W/kg versus 2.41(0.43) W/kg; P < 0.01). A negative correlation was observed between the duration of palliative shunts and diffusion capacity of the lung for carbon monoxide at rest at ventilatory anaerobic threshold (r = -0.8635 and -0.9108 respectively). A shunt placed before definitive repair impairs the long-term working capacity, probably by diminishing the diffusion capacity of the lung for carbon monoxide, especially if the shunt is in place for more than 20 months.

Long-term follow-up of brachial artery ligation in children

Ligation of the brachial artery in the antecubital fossa in children can be performed without limb loss, but the effect on subsequent limb growth is unknown. From 1969 to 1974, brachial artery ligation for insertion of a Scribner shunt was performed in 27 patients with a mean age of 8.4 years (range, 3 to 15 years). We examined 11 patients, all with functional renal transplants, a mean of 15.8 years (range, 13 to 18 years) after ligation. Nine patients had unilateral ligation and two had bilateral ligation. The patients were examined for arm length and circumference, resting blood pressure at the wrist, neurologic function of the arm, and exercise tolerance. A significant difference in resting arterial pressures in the ligated extremity was uniformly noted (mean systolic pressure 106 mmHg versus 123 mmHg in 7 patients, p less than 0.01). Although no patient specifically complained of problems with the ligated side, six of nine patients with unilateral ligation experienced arm discomfort on stress testing. There was no significant difference in limb circumference or length between the ligated and unligated extremity. Ligation of the brachial artery in growing children with renal disease caused diminished resting pressure and mildly decreased exercise tolerance but did not lead to limb loss or subsequent growth abnormalities.

Disruption of a modified Blalock-Taussig shunt by rapid deceleration injury

A case is presented of an 8-year-old child who had tension hemothorax after disruption of a modified Blalock-Taussig shunt 2 weeks postoperatively. A rapid deceleration mechanism was responsible for the injury.

Left subclavian flap aortoplasty for coarctation of the aorta: effects on forearm vascular function and growth

This study evaluated vascular function and growth of the forearm in nine children (mean age 9.2 years) who had undergone left subclavian flap aortoplasty for the infantile type of coarctation of the aorta many years (mean 9.0) earlier. Variables used to investigate bilateral forearm vascular function included forearm blood flow and resistance measured by strain gauge plethysmography under rest conditions, in response to 30 s of static handgrip exercise at 40% maximal voluntary contraction and in response to 10 min of forearm arterial occlusion (that is, the reactive hyperemic blood flow response). Forearm growth was ascertained by measuring right and left forearm volumes, lengths, circumferences and skinfold thickness. Mean arterial pressure at rest in the right and left arms differed by 9% (right 78.2 +/- 2.1, left 71.0 +/- 2.7 mm Hg; p less than 0.05). Forearm blood flow, however, was not significantly different between the surgically altered left arm and the normal right arm under any of the study conditions. Likewise, forearm vascular resistance was not statistically different under any conditions, although the left arm tended to have a lower resistance at rest (right 23.5 +/- 3.2, left 18.7 +/- 2.0 mm Hg.min.100 ml/ml; p = 0.057). Left forearm anthropometric measurements showed a 9% reduction in volume and a 3% reduction in circumference and length. In addition, skinfold thickness tended to be larger on the left arm, suggesting that this limb had a smaller muscle mass. In conclusion, early repair with a subclavian flap does not impair vascular function in the altered limb and is associated with only minor reductions in forearm growth variables. Hence, left subclavian flap aortoplasty appears to be a safe and effective procedure for repair of coarctation of the aorta.

Handgrip strength after the Blalock-Taussig shunt: 14 to 34 year follow-up

To determine the long-term functional impact of the Blalock-Taussig (BT) shunt, we studied handgrip strength in 56 patients (10-28 years) following total repair of tetralogy of Fallot. Of the 56, 16 (29%) had a previous right BT shunt, 5 of 56 (9%) had a previous left BT shunt, and the remaining 35 patients either had a Potts shunt or primary total repair. The mean age at the time of right BT was 2.8 +/- 1.6 (SD) years, left BT 1.7 +/- 1.2 years, and total repair for all patients was 7.1 +/- 2.2 years. Mean age at the time of study was 26 +/- 9 years. Right-and left-handgrip strength were measured with a Jamar dynamometer, averaging the results of grip position 2, 3, and 4 to accommodate variation in hand size. Since absolute values of hand strength were strongly associated with sex (p = 0.006) and body surface area (p = 0.016), we calculated the ratio of right-hand to left-handgrip strength (RL ratio). The RL ratios were: 0.98 +/- 0.13 (right BT), 1.21 +/- 0.11 (left BT), and 1.13 +/- 0.16 (no BT): (p = 0.004 right BT vs. no BT, p = 0.07 left BT vs. no BT, Wilcoxon rank sum test). Thus, although frequently clinically inapparent, handgrip strength tested many years post-BT shunt is reduced on the side of the shunt.

Palliation in cyanotic congenital heart disease. Fifteen years' experience of various shunt procedures

During the past 15 years, 143 systemic pulmonary shunt procedures have been performed in 117 patients. These have been evaluated for their clinical effectiveness, the need for a repeat operation and the mortality; particular attention was paid to the Teflon shunt. Variations were found in shunt performance, depending on the primary defect, the type of shunt that was employed and the year of operation. The overall shunt patency after three years was 77% (85% with the Teflon shunt). Although, in our total experience, mortality at 30 days was 12%, with 16% late deaths, "modified Blalock" (Teflon) shunts had only a 5% hospital mortality and a 5% late mortality within three years. Pulmonary atresia, without a ventricular septal defect, is often insufficiently palliated by a shunt alone. Ten of 82 patients with variations of the tetralogy complex died within 30 days of operation, and a further 11 died in the late follow-up period. Six of these 21 shunts were patent at autopsy. Less common defects, such as univentricular heart, transposition and double-outlet right ventricular connections, that are associated with pulmonary stenosis had no early mortality but led to four late deaths among 27 patients. Two of the four patients had patent shunts. Results in the early part of this experience were less than acceptable owing to inferior shunting techniques, postoperative management errors and, particularly, inadequate follow-up surveillance. With correction of these factors we find that the modified Blalock shunt provides very good early and late mortality results, with excellent clinical palliation and patency rates.

Prognosis of Fallot's tetralogy after palliative operations: 10-25 year follow-up

The condition of 350 patients with Fallot's tetralogy (FT) who had palliative surgery (aortopulmonary shunt or transventricular valvotomy) was reviewed 10-25 years later: 136 patients (38%) are alive without any further operation, 106 (30%) have recovered completely, and 108 (31%) have died. Actuarial survival at 25 years of the patients who had palliation was 50% compared to 83% for the group who subsequently had complete correction. After the first five years the mortality rates became 5% per year. Of the patients who were not reoperated upon, 33% felt that the quality of their life was normal, 40% were limited, and 27% were severely limited. The older the patient at palliative procedure, the better the clinical course and the longer the interval before another operation, if the latter was needed at all. Of the patients who had a Brock procedure, the survival rate at 25 years was 80% and the clinical condition was good in 72% of the patients who had not been reoperated upon. Comparison with the natural history of unoperated FT reported by others indicates that the palliative procedures prolonged life in our series; mortality continued at a steady rate for a few years after palliative surgery, probably as a function of the severity of the anatomical and functional abnormality, and independently of the age at which the palliative procedure was performed. Among the palliative procedures, the Brock operation was followed by the best results both in relieving symptoms and in prolonging life.

Experience with the modified Blalock-Taussig operation using polytetrafluoroethylene (Impra) grafts

Between June 1978 and January 1982, 115 patients underwent 122 subclavian artery-pulmonary artery shunts using polytetrafluoroethylene (PTFE Impra) grafts. Forty-six of the patients had a ductus dependent pulmonary circulation, the patency of which was maintained by an infusion of prostaglandin E2 in 29 cases. There were nine hospital deaths, four of which were related to shunt failure. Five patients underwent a second shunt procedure within one week of the first. There were two cases of late graft occlusion. Twelve shunts were considered to have failed. The actuarial estimate of shunt patency was 90% (+/- 3%) at two years for all patients and 74% (+/- 10%) for neonates. There was no statistically significant difference in two year shunt patency between 4 mm grafts (88 +/- 5%) and 6 mm grafts (96 +/- 3%). The modified Blalock shunt using a PTFE graft is an effective pulmonary-systemic shunt with a good short term patency.

Postoperative angiographic assessment of modified Blalock-Taussig shunts using expanded polytetrafluoroethylene (Gore-Tex)

Thirty-six of 87 modified Blalock-Taussig shunts done with expanded polytetrafluoroethylene (Gore-Tex) were restudied angiocardiographically. In 7 patients the study was carried out within 1 month of the shunt operation because the patients failed to make satisfactory clinical progress. Two shunts were occluded and 1 ws stenosed; all 3 were in neonates. The remaining 29 patients were reinvestigated electively between 5 and 29 months postoperatively and had a 97% shunt patency rate. Because of the rather high incidence of irregular or stenosed shunts among neonates with 4 mm conduits, we now prefer to use a larger conduit even in this age group.

Leg growth following umbilical artery catheter-associated thrombus formation: a 4-year follow-up

Fourteen children were re-examined 4 years following the radiographic demonstration of umbilical artery catheter associated thrombus formation. Positive correlations could not be established between radiographically determined femoral and/or tibial lengths, length differences, pulse pressure differences, and the location of thrombi noted on the 1971 aortograms.

Oxygen uptake arterial blood gases and blood lactate concentration during submaximal and maximal exercise in adult subjects with shunt-operated tetralogy of fallot

Ten female and six male adult subjects with shunt-operated tetralogy of Fallot have been studied at rest and during submaximal and maximal exercise on an average 20 years after the palliative operation. There was a considerable reduction in the aerobic work capacity, maximal oxygen uptake (VO2) being 1.00 1/min STPD. Though ventilation (VE) was out of proportion to VO2 as indicated by an abnormally high ventilation equivalent (52.1), values for VEmax were low (50.81/min BTPS) and of approximately the same order as in a comparable group of totally corrected TOF patients. In spite of increased VE in relation VO2 the PaCO2 increased from 30 mmHg at rest to 49 mmHg during maximal exercise, while PaCO2 decreased from 60 mmHg at rest to 44 mmHg during submaximal exercise I. During heavier exercise no further fall was noted. Base excess decreased from -2.9 to -9.8 mEq/l. Thus a combined respiratory and metabolic acidosis was at hand during exercise, the metabolic component, however, being normal. Maximal blood lactate concentrations were low (5.8 mmol/l) and contrasted with the high intramuscular lactate concentrations earlier reported in some of the patients. The low values found for VO2 max indicate that a palliative operative procedure in TOF is no alternative to an intracardiac repair in the long-term course. The two main factors limiting exercise tolerance were acidosis and accumulation of lactate within the muscle cell.

Ascending aorta to right pulmonary artery anastomosis. Immediate results in 123 patients and one month to six year follow-up in 74 patients

An intrapericardial ascending aorta-to-right pulmonary artery anastomosis was performed in 123 patients with cyanotic congenital heart disease associated with pulmonary stenosis or atresia during the eight year period from 1964 through 1971. While there were 20 early postoperative deaths (16%), 90% (93 patients) of the 103 survivors were symptomatically improved.

In the postoperative evaluation, 74 patients (72% of the survivors) returned for follow-up examination, which included cardiac catheterization in 57. The anastomosis was nonfunctioning in ten (13.5%) of these 74 patients and in an additional 13 (17.5%) patients, clinically silent right pulmonary artery stenosis was demonstrated angiographically at the anastomosis site. Clinical improvement had been maintained in the 64 patients with an open anastomosis (audible continuous murmur or angiographically demonstrated patency) including the 13 patients with acquired pulmonary stenosis at the operative site. Persistent right pulmonary artery stenosis was demonstrated in nine of the 14 patients who had cardiac catheterization after intracardiac repair of the congenital heart defect and closure of the anastomosis, but this was insignificant in four of these nine.

The ascending aorta-to-right pulmonary artery anastomosis provides symptomatic improvement for most patients with cyanotic congenital heart disease associated with pulmonary stenosis but may produce right pulmonary artery obstruction requiring attention at the time of total intracardiac repair.

Systemic-pulmonary arterial shunts in the first year of life

Results of systemic to pulmonary arterial shunts during the first year of life are reported in 86 infants under one year of age. Survival rates were highest in older patients and among infants whose basic cardiac defects were considered to be eventually amenable to surgical repair. Persistent hypoxia accounted for the majority of deaths. Congestive heart failure secondary to too large anastomoses occurred in 32.5% of Waterston shunts, but could be successfully managed medically in the majority of patients. Surgical revision of the shunt was accomplished successfully in two infants with subsequent alleviation of symptoms. Congestive heart failure occurred in only one of 26 patients after a Blalock shunt. Ten of the twelve patients in this series survived open-heart repair for cardiac lesions. It will eventually be necessary to compare these data with the results of single stage corrective surgery in the infant group.

Ascending aorta-right pulmonary artery shunt in infants and older patients with certain types of cyanotic congenital heart disease

A side-to-side anastomosis between the ascending aorta and the right pulmonary artery was created in 80 infants (less than 1 year of age) and in 61 older children with a variety of cyanotic cardiac abnormalities in which there is pulmonary stenosis or atresia. Seventy-one per cent of the infant group and 90% of patients over 1 year of age were long-term survivors (up to 6 years).

Tetralogy of Fallot was the most commonly encountered anomaly in all 141 patients (66%); transposition of the great vessels and pulmonary stenosis occurred in 18%; and tricuspid atresia with pulmonary stenosis in 10%.

The presence of an excessively large shunt anastomosis (55% of deaths) and additional (unrecognized) other anomalies (26%) were major causes of postoperative deaths.

In patients in whom a systemic-pulmonary artery anastomosis is required, this operation is the procedure of choice in infants under 1 year of age. It is also of value in older patients if a Blalock-Taussig shunt cannot be performed.