Arm-leg Gradient Research Articles

Myocardial strain pattern progress in patients with Coarctation of the Aorta undergoing aortic stenting.

Ventricular function evaluation in coarctation of the aorta (CoA) has become more sophisticated and precise with speckle tracking, revealing subclinical changes. However, CoA stenting treatment effects in on myocardial strain are still controversial. This study aimed to estimate the extent to which changes in left ventricular global longitudinal strain (LV GLS) occur in patients with CoA who undergo stenting. The study included 21 patients with CoA (median age: 15 years [8-39]) and 21 healthy individuals matched by age and gender. Clinical and echocardiographic evaluations were performed 1 day before, 6 months, and 1 year after stenting. Correlations between LV GLS and arm-leg gradient, isthmus gradient on echocardiogram, age at intervention, left ventricular mass, and ejection fraction were tested. Before treatment, patients with CoA had lower LV GLS than the control group (-18.4% ± 1.96 vs -21.5% ± 1.37; P < .01), showing significant increase to -19.4% ± 2.1 at 6 months and -20.7% ± 2.19 at 1 year, P < .001. Only 28.5% (6 patients) had preserved GLS before treatment, improving to 80.9% (17 patients) in 1 year. The only variable correlated with low LV GLS values before treatment was age at intervention (Spearman's index = -0.571; P = .007). Percutaneous therapy showed significant LV GLS improvement 12 months after aortic stenting. Older patients have lower GLS, suggesting that early intervention may have positive effects on preservation of LV systolic function.

Is the burden of late hypertension and cardiovascular target organ damage in children and adolescents with coarctation of the aorta after early successful repair different to healthy controls?

Cardiovascular morbidity is high in patients with coarctation of aorta even after successful repair. This study aimed to assess the frequency of late hypertension and the relationship between ambulatory hypertension and cardiovascular target organ damage in children and adolescents after early and successful repair of coarctation of the aorta. Twenty-five children and adolescents (mean age 13.5 ± 3.43 years) with repaired coarctation of the aorta (median age at repair 4 months, arm-leg gradient <20 mmHg) and 16 healthy controls were included. Office and ambulatory blood pressure, pulse wave velocity, and left ventricular mass index were assessed. Both day- and night-time systolic blood pressure standard deviation score and left ventricular mass index were significantly higher in patients compared to controls (p ≤ 0.001 for all), whereas pulse wave velocity did not differ. The prevalence of masked hypertension, isolated nocturnal hypertension, and left ventricular hypertrophy were 40, 28, and 24%, respectively. Left ventricular mass index was higher in patients with sustained hypertension, masked hypertension, and normotension compared to controls (p < 0.05). In multivariate analysis, higher night-time systolic blood pressure standard deviation score was the only independent predictor of left ventricular mass index. The present study reveals a high prevalence of masked hypertension, isolated nocturnal hypertension, and left ventricular hypertrophy in children and adolescents with coarctation of the aorta even after early and successful repair. Ambulatory blood pressure monitoring should be considered to diagnose hypertension. All coarctation of aorta patients should be followed up lifelong and encouraged to establish a healthy lifestyle starting from childhood.

A Novel and Simple Percutaneous Technique to Treat a Complex Pseudoaneurysm of Post-Aortic Coarctation Patch Aortoplasty

A 49-year-old woman underwent Dacron patch aortoplasty for coarctation of the aorta (CoAo) at 5 years of age. She was under antihypertensive treatment and had a 20-mm Hg right arm-leg gradient in the last clinical visit. Electrocardiogram was normal and transthoracic echocardiography showed a

Aortic coarctation repair in neonates with intracardiac defects: the importance of preservation of the lesser curvature of the aortic arch.

The aim of this study was to evaluate the mid-term outcomes of a strategy for repair of coarctation of the aorta (CoA) and hypoplastic aortic arch (HAA) with a modified, extended end-to-end repair that preserves the lesser curvature of the aortic arch in neonates with intracardiac defects. We studied 21 neonates who underwent CoA repair and remote intracardiac repair (2000-2013). Fifteen patients had HAA, and six patients had no HAA. Follow-up ranged from 0.4 to 12.8 years (median, 7.5 years), and all patients underwent cardiac catheterization and blood pressure measurement in both the arms and legs. The overall median age at the time of CoA repair was seven days and the median age at the time of intracardiac defect repair was 18.6 months. There were no hospital deaths and one case had recoarctation (4.8%). The overall mean pressure gradient at the latest follow-up was 3.4 ± 5.7 mmHg. Critical deformation of arch geometry was not found. No patient had hypertension or an abnormal arm-leg gradient. There was no difference in the cardiac catheterization data or blood pressure between patients with and without HAA. A modified, extended end-to-end repair for CoA and HAA resulted in a low rate of recoarctation, no operative mortality, maintenance of a smooth rounded arch, and normal blood pressures in the arms and legs during mid-term follow-up. These results suggest that this technique may be acceptable for repair of CoA and HAA in neonates with intracardiac defects.

Abstract 19100: Comparison of Exercise Blood Pressure Response in Patients With Coarctation of Aorta: Surgical Repair vs. Endovascular Stent

Background: Percutaneous stent placement has been shown to be a safe and effective treatment option for patients with coarctation of the aorta. Immediate post-procedural and short term hemodynamic assessments comparing stent placement to surgical correction show equivalency. Little is known about the effects of either treatment modality on blood pressure response during exercise. Methods: This study prospectively compares the hemodynamic response to exercise by treadmill testing in patients at least one year after intervention. Patients included were greater than seven years of age without complex congenital heart disease or single ventricle physiology. Patients underwent standard Bruce Protocol treadmill testing with periodic arm leg blood pressure and metabolic measurements. Results: Twenty-five patients underwent treadmill testing: 18 with surgical correction, 7 with stent placement. Median age was 13 years (IQR: 11-15.5yrs). The median arm-leg gradient prior to exercise was 12mmHg (IQR: 9.25-21.75mmHg) for surgical patients and 16mmHg (IQR: 3 - 25mmHg) for stented patients. The median peak exercise arm-leg gradient was 28mmHg (IQR:16 - 44mmHg) for surgical patients and 30mmHg (IQR:17.5 - 40mmHg) for stented patients. The median increase in the arm leg gradient with exercise was 16mmHg for surgical patients and 14mmHg for stented patients. Median Actual VO2Max/Predicted VO2Max was 100% for surgical patients compared to 96% for stented patients. Median Actual VO2Max/Predicted VO2Max was 100% for surgical patients compared to 96% for stented patients. Conclusions: Few studies have compared surgery and endovascular stenting for coarctation of the aorta, with only one prior study comparing the effects of exercise on blood pressure. Stenting and surgery offer excellent hemodynamic results acutely and at maximal exercise. Stent placement demonstrates equivalent results in blood pressure response during exercise testing when compared to surgical therapy.

Exercise Evaluation of Upper- versus Lower-Extremity Blood Pressure Gradients in Pediatric and Young-Adult Participants

The aim of this study was to provide a normal reference for arm-leg blood pressure gradients in normal pediatric and young-adult patients before and after exercise. We assessed 216 normal participants by physical or echocardiographic exam, maximally tested using the James Cycle Protocol, with arm and leg blood pressures taken pre- and postexercise. Arm-leg gradients significantly increased from -5 mmHg at rest to 4, 2, and 1 mmHg 1, 3, and 4 min postexercise (p < .05). There was a small, statistically significant increase in arm-leg blood pressure with exercise, which is probably clinically insignificant. These data serve as a normal reference.

Exercise Hemodynamics in Pediatric Patients After Repair of Coarctation

PURPOSE: Patients with coarctation of the aorta are often treated by surgical resection and end to end anastamosis. More recently, this lesion has been remedied by percutaneous stent placement. We compared the exercise hemodynamics of stent treatment versus end to end anastamosis repair. METHODS: We evaluated 10 patients (7 males, median age 13.3 yrs, STENT group) treated with a stent versus 18 patients (12 males, median age 13.7 yrs, SURGERY group) repaired by end to end anastamosis and compared them to 16 normal patients (7 males, median age 13.9 yrs, CONTROL group). All patients were exercised with the James cycle ergometer protocol to volitional fatigue. Arm-leg blood pressures were taken supine at rest and 1 minute post exercise. RESULTS: There was no significant difference in the height, weight and age between the three groups. The STENT group was 1.17 +/− 0.7 years post-op and the SURGERY group was 11.2 +/− 4.0 years post op. Total working capacity (TWC), Exercise Time, maximal HR, maximal VO2, and maximal Cardiac Output were not significantly different between the groups. Maximal systolic blood pressure and arm-leg gradient 1 minute post exercise in STENT and SURGERY were significantly increased when compared to CONTROL, but not from each other.TableCONCLUSION: Coarctation repair by stent placement avoids the risk of a thoracotomy, and yields post-repair exercise hemodynamics similar to that of surgery patients. However, there is a significantly higher systolic blood pressure at max exercise and a greater arm-leg gradient one minute post exercise in coarctation patients compared to controls. Regardless of the type of corrective procedure, patients with coarctation of the aorta demonstrate similar responses to exercise.

Use of Partial Cardiopulmonary Bypass for Coarctation Repair Through a Left Thoracotomy in Children Without Collaterals

Paraplegia is a devastating complication of coarctation of the aorta (COA) repair. Since 1990 we have used left atrium-to-descending aorta cardiopulmonary bypass (CPB) for COA repair in patients with inadequate collaterals. We reviewed the results with that strategy and compared this CPB group with COA repairs in which CPB was not used to see whether there was any increase in morbidity or delay in recovery. From 1990 to 2006, 11 patients with COA were identified to have inadequate collaterals based on preoperative examination and intraoperative arterial monitoring and test clamp. Left thoracotomy with left atrium-to-descending aorta CPB was used in all. Age ranged from 4.2 to 17.4 years (mean, 8.7 +/- 4.6 years). Two were reoperations for recurrent COA, 3 patients had four prior transcatheter balloon dilatations. One patient had aberrant origin of the right subclavian artery. Operative techniques included resection with extended end-to-end anastomosis (n = 6), interposition graft (n = 4), and patch repair (n = 1). During the same period 71 patients older than 1 year of age had COA repair without CPB. Age ranged from 1.1 to 46.1 years (mean, 7.6 +/- 7.1 years; p = 0.6). Preoperative imaging of CPB patients demonstrated absence of collaterals (n = 7), possible collaterals (n = 2), small collaterals (n = 1), and anomalous origin of the right subclavian artery (n = 1). Preoperative arm leg gradient in CPB patients was 36.0 +/- 9.0 mm Hg versus 49.9 +/- 15 mm Hg in non-CPB patients (p < 0.01). Mean distal femoral artery pressure with aortic test clamp was 34.3 +/- 4.8 mm Hg in CPB patients versus 49.8 +/- 12.4 mm Hg in non-CPB patients (p < 0.01). Mean CPB flow was 53% +/- 7.3% of calculated total flow. Cardiopulmonary bypass time ranged from 17 to 46 minutes (mean, 27.5 +/- 9.7 minutes). Aortic clamp time in CPB patients ranged from 15 to 33 minutes (mean, 21.6 +/- 6.3 minutes). In the non-CPB group aortic clamp time ranged from 10 to 50 minutes (mean, 23.4 +/- 7.5 minutes; p = 0.5). In the CPB group length of stay ranged from 3 to 7 days (mean, 4.9 +/- 1.3 days), and in the non-CPB group length of stay ranged from 3 to 12 days (mean, 4.7 +/- 1.4 days; p = 0.5). No patient had a neurologic complication. There were no other major complications in the CPB group (eg, bleeding, recurrent laryngeal nerve injury, re-COA). Preoperative imaging and a lower arm-to-leg gradient in this series of COA patients suggested inadequate collateral circulation with the potential need for CPB. A femoral artery pressure of less than 45 mm Hg during test clamp was used as an indication for partial CPB. The use of left atrium-to-descending aorta CPB with just over 50% calculated total flow protected the spinal cord in a safe and expeditious fashion. Use of left heart bypass did not affect morbidity or recovery time as compared with COA repair in non-CPB patients.

Development of exercise-induced arm-leg blood pressure gradient and abnormal arterial compliance in patients with repaired coarctation of the aorta

Often, the lack of systemic arterial hypertension and the lack of a resting arm-leg blood pressure gradient are used to assess the adequacy of the anatomic result after intervention for coarctation of the aorta (CoA). Some patients with no arm-leg gradient at rest may develop a gradient with exercise, leading caregivers to question the success of the repair. It is not clear what the prevalence is of patients who have undergone a successful intervention for CoA and have no arm-leg gradient at rest but develop a significant gradient with exercise and which factors may predict the development of an arm-leg gradient with exercise. This study evaluates the prevalence and predictors of an exercise-induced arm-leg gradient in subjects who have undergone an apparently successful intervention for CoA.

Effects of morphologic restenosis, defined by MRI after coarctation repair, on blood pressure and arm-leg and Doppler gradients.

Ten years after coarctation repair, 36 adolescents and young adults were studied in order to evaluate the relationship of anatomy at the resection site to blood pressure and arm-leg and Doppler gradients. The patients underwent magnetic resonance imaging (MRI), exercise testing, and continuous wave (CW) Doppler echocardiography. On MRI, residual narrowing at the resection site was measured as 1-(phi anastomosis/ phi descending aorta) and expressed as percent stenosis. Residual stenosis on MRI was negatively correlated with the leg pressure at rest (P = 0.0003) and during exercise (P = 0.002). Residual stenosis correlated positively with the arm-leg gradient at rest (P < 0.0001) and during exercise (P < 0.0001) and with the peak CW Doppler gradient across the anastomosis (P < 0.0001). However, residual stenosis was not related to the systolic blood pressure of the arm at rest or during exercise. The systolic arm pressures did not differ between patients with residual stenosis of less than 30% (group I), patients with residual stenosis of equal to or greater than 30% but less than 45% (group II), and patients with residual stenosis of equal to or greater than 45% (group III). In conclusion residual anatomic stenosis influences blood pressure in the legs, the arm-leg gradient, and the Doppler gradient across the anastomosis. Arm hypertension late after coarctation repair seems not to be related to residual stenosis, and the benefit of reintervention in these patients remains questionable.

Arm-leg pressure gradients on late follow-up after coarctation repair. Possible causes and implications.

Seventeen years after coarctation repair, 36 patients were studied by magnetic resonance imaging and exercise testing to measure residual anatomical stenosis and hormonal response to exercise, and to evaluate their effect on arm-leg gradients and on exercise hypertension. The systolic arm pressure, leg pressure and arm-leg gradient were measured at rest and during exercise. Active renin and catecholamines were measured in the plasma at rest and after peak exercise. On magnetic resonance imaging 18 patients had residual stenosis of less than 30% (group I) and 18 had residual stenosis of equal to or more than 30% (group II). At peak exercise, the arm pressure was 235 (133-296) mmHg in group I and 241 (157-286) mmHg in group II (ns), the leg pressure was 138 (111-173) mmHg in group I and 114 (75-154) mmHg in group II (P = 0.002). The adrenalin increase from rest to exercise was 32.7 +/- 9.1 pg.ml-1 in the patients with exercise hypertension and 3.1 +/- 4.7 pg.ml-1 in the patients who remained normotensive during exercise (P = 0.02). In conclusion, residual anatomical stenosis leads to a pressure drop in the legs, which influences the arm-leg gradient. Arm hypertension is not related to anatomical narrowing but to interaction of enhanced sympathetic nerve activity and structural and functional abnormality of the precoarctation vessels.

Reoperation for recurrent aortic coarctation

Recurrence of stenosis is a complication of coarctation repair associated with major long-term morbidity. Persistent or exercise-provoked hypertension may indicate recurrent coarctation. Patients failing or not amenable to balloon dilation should be managed surgically. A retrospective chart review was performed. Forty-three patients were identified as having undergone repeat surgical intervention for recurrent aortic coarctation between the years 1976 and 1993 at The Hospital for Sick Children in Toronto. Seventy percent of the children had other congenital cardiac anomalies. Eighty-six percent of patients initially treated by subclavian flap aortoplasty or end-to-end anastomosis were managed at reoperation by patch aortoplasty, and 26% of patients also required augmentation of the transverse arch (under hypothermic circulatory arrest) for accompanying hypoplasia. Three patients underwent a second reoperation; all were treated at this reoperation with tube graft interposition. No ischemic spinal injury occurred in patients managed with either simple proximal aortic cross-clamping or cardiopulmonary bypass. No patient treated with transverse arch augmentation required further surgical intervention. Mortality at reoperation was 7% (3 patients), similar to that of first-time coarctation repair. At follow-up (mean duration, 4.5 years), 57% of patients are normotensive, with no measurable arm-leg gradient.

Exercise-induced hypertension in the arms due to impaired arterial reactivity after successful coarctation resection

Exercise-induced hypertension of the arms is a wellknown late complication after coarctation repair. Residual narrowing at the anastomosis site as well as abnormalities of the precoarctation arterial system may be the cause of this problem. Blood pressure response to exercise and flow-mediated arterial dilatation of the arms and legs were studied in 29 young adults after successful coarctectomy in childhood and compared with 13 control subjects. Peak exercise systolic blood pressure was significantly higher in patients than in control subjects: 238 versus 199 mm Hg (p = 0.007). Both groups had a positive systolic arm-leg gradient during exercise: 59 versus 37 mm Hg (p = 0.05). Flow-mediated dilatation of the brachial artery was significantly reduced in patients compared with that in control subjects: 4.2% (range 0% to 9.4%) versus 9.4% (range 3.7% to 16%) (p < 0.0001). Flow-mediated dilatation of the femoral artery was similar in both groups. Dilatation of the brachial artery was inversely correlated to peak exercise systolic pressure in the study patients (r = −0.427, p = 0.02). A positive arm-leg exercise gradient partly represents physiologic circulatory adaptation to ergometry and is therefore not appropriate for evaluation of residual narrowing. Exercise-induced hypertension of the arms late after coarctation repair is caused by impaired arterial reactivity, which results from structural or functional abnormality, or both.

Long-term follow-up of coarctation of the aorta repaired by patch angioplasty

The long-term complications of patch plasty repair for coarctation of the aorta were assessed retrospectively in 119 patients who were operated upon from 4 days to 13 years of age. There were 7 late deaths and 17 patients were lost to follow-up. Thus 95 patients were followed up for a minimum period of 3 years (mean 6.3 years). In addition, graded exercise tests were performed on 15 patients and 11 normal controls, measuring systolic blood pressure response and arm-leg blood pressure gradients. In this series, 16 patients (17%) were hypertensive, while 25 (26%) had a resting systolic arm-leg gradient > 20 mm Hg. Re-coarctation occurred more frequently when surgery had been undertaken under 1 month of age. Review of chest X-rays revealed calcification in the patch in 4 patients, one of whom subsequently went on to aneurysm formation. In a second child aneurysm formation was detected at repeat operation. Exercise tests showed a significantly higher systolic arm pressure in patients (mean: 165.3 mm Hg) when compared to controls (mean: 139.2 mm Hg) ( P = 0.017) and a significant increase in arm-leg systolic gradient viz. 36 and 5.9 mm Hg, respectively ( P = 0.0016). A good correlation was found between the systolic arm pressure and the systolic arm-leg gradient after exercise ( r = 0.822; P = 0.0001). We conclude that the most important long-term complication following an aortic patch plasty, is re-stenosis. The development of an aneurysm was observed only twice. We believe that this apparently rare occurrence, as assessed on chest radiographs; is related to the young age (53% under 1 year) at which the repairs were carried out. Another possible reason may be that the follow-up period is not yet long enough.

Altered systolic and diastolic function in children after “successful” repair of coarctation of the aorta

We investigated whether left ventricular (LV) structural or functional abnormalities persist in children on long-term follow-up after successful correction of coarctation of the aorta. Two-dimensional directed M-mode and Doppler echocardiographic examinations were performed on 11 such subjects and 22 age-matched control subjects. Digitized tracings were made from M-mode recordings of the LV and Doppler mitral valve inflow recordings to measure septal, posterior wall, and LV dimensions, LV mass, shortening fraction, peak shortening and lengthening velocities, diastolic filling time, peak E velocity, peak A velocity, and velocity time integrals. Despite group similarities in age, body size, and systolic blood pressure, greater fractional shortening ( p = 0.0001), indexed peak shortening velocity ( p < 0.001), and greater LV mass index ( p < 0.05) were seen in the coarctation group in the face of lower LV wall stress ( p = 0.0001). LV mass index correlated with the resting arm-leg gradient, which ranged from −4 to +10 mm Hg. The coarctation group had decreased early filling ( p < 0.006) with compensatory increased late diastolic filling ( p < 0.05). Diastolic filling abnormalities were prominent in the older coarctation subjects and were related to both systolic blood pressure ( p < 0.001) and LV mass index ( p < 0.01). Despite apparently successful repair of coarctation of the aorta, persistent alterations in both systolic and diastolic LV function and LV mass are present in children at long-term follow-up, which are related to the resting arm-leg gradient. We speculate that these small measured arm-leg gradients represent persistent alterations in flow, which may result in LV hypertrophy and hyperkinesia.

Utility of Exercise Testing to Assess Aortic Recoarctation.

Because it is not known how often and how uniformly exercise testing is used to "unmask" recurrent or persistent coarctation of the aorta, this study was designed to determine (a) the frequency with which exercise testing is used by the clinician to evaluate patients after coarctation repair, and (b) the hemodynamic measures obtained with exercise that are considered to be indicative of significant persistent or recurrent coarctation. Questionnaires were sent to 80 randomly selected pediatric cardiologists; 49 were returned completed. About half of the respondents performed exercise testing (ET) on all of their patients after coarctation repair and 75 % tested at least half. Those who supervised an exercise laboratory used ET for a significantly greater number of their patients. In descending order, rest arm-leg gradient (ALG), maximal exercise systolic blood pressure (MXBP), and postexercise ALG were considered the most important indicators of significant recoarctation. The majority of respondents made decisions based on data from the ET that were consistent with published guidelines.

Cuff pressures and Doppler gradients after coarctectomy. A long-term follow-up.

Fourty-six adult patients operated on as children with resection and end to end anastomosis because of coarctation of the aorta were studied. The age at operation was 7 to 13 years (mean age 10 years) and at follow-up 18 to 28 years (mean age 21 years). Arm and thigh cuff pressure was measured at rest, during and immediately after submaximal exercise. The systolic gradients were also estimated using continuous wave Doppler. Systolic blood pressure at rest was 150 mmHg or more in 12 patients (26%). The cuff pressure at rest correlated well with arm-leg gradients at rest and at work, and also with the Doppler gradients at rest. Doppler gradients slightly underestimated invasively measured gradients. The results imply that postoperative hypertension was explained by residual mechanical obstruction.

Exercise-induced hypertension after repair of coarctation of the aorta: Arm versus leg exercise

The etiology of exercise-induced upper limb hypertension after repair of coarctation of the aorta is unknown. We hypothesized that blood flow across the coarctation repair site is a major determinant of such exercise-induced hypertension. Because arm ergometry should produce a smaller increase in descending aortic blood flow than treadmill exercise, we compared the changes in upper limb pressure and the coarctation gradient produced by each type of exercise at equivalent levels of heart rate and peak oxygen consumption in 28 children with repaired coarctation of the aorta. The children were classified into three groups: Group I, resting gradient less than 15 mm Hg and treadmill gradient less than 20 mm Hg; Group II, resting gradient less than 15 mm Hg and treadmill gradient greater than 20 mm Hg; and Group III, resting gradient greater than or equal to 15 mm Hg. Twelve children with no heart disease served as control subjects. All children were exercised to exhaustion with 45 minutes' rest between the two exercise protocols. There were no differences in maximal heart rate and oxygen consumption between the two types of exercise. In all groups, treadmill exercise produced a larger increase in arm systolic blood pressure and arm-leg gradient than did arm exercise. With treadmill exercise coarctation Groups II and III developed a greater rise in both arm-leg gradient and arm systolic pressure than was observed in the control subjects (p less than 0.05). However, with arm exercise, Group III developed a significantly greater rise in both arm pressure and arm-leg gradient (p less than 0.05) than was observed in the control subjects.

Changing Trends in the Surgical Treatment of Coarctation of the Aorta

From 1974 through 1983, 107 patients 4 days to 27 years old underwent 115 operations for treatment of coarctation of the aorta. Thirty-two patients were infants (1 year old or younger), and 28 of them were newborns. All newborns were seen with congestive heart failure. Seventy-one patients were seen with hypertension. Associated anomalies were present in 72 patients (67%). Resection was performed in 48 patients, patch aortoplasty in 16, bypass of the coarcted segment in 15, and left subclavian artery flap angioplasty (LSAFA) in 36. Ligation of a patent ductus arteriosus was simultaneously performed in 28 patients and pulmonary artery banding, in 4. Follow-up was 6 months to 9.2 years. There was a significant difference in aortic cross-clamp time between 26 patients who had resection (37.9 ± 12.9 minutes) (mean ± standard deviation) and 32 patients who had LSAFA (22.9 ± 7.7 minutes) ( p < 0.05). Six patients died within thirty days after operation; 5 of them had resection, and 1 had bypass. Major postoperative complications included bleeding requiring exploration in 3 patients (2 after resection and 1 after LSAFA) and paraplegia in 1 patient after reoperation (resection) for recurrent coarctation 3 years after patch aortoplasty. Paradoxical hypertension was observed in 13 patients, and sustained systemic postoperative hypertension developed in 11 after effective repair of coarctation. There was no significant difference in early postoperative arm-leg pressure gradients between the types of operation or the various age groups. Among patients operated on in infancy, arm-leg gradients at latest follow-up were significantly lower in 11 patients after LSAFA (6.7 ± 9.4 mm Hg) than in 4 patients after resection (32 ± 27.1 mm Hg) ( p < 0.025). In older patients, no significant difference in late gradients was observed. Left subclavian artery flap angioplasty is effective and safe for the treatment of coarctation of the aorta in newborns and infants.

Digital blood pressure in patients with peripheral arterial disease.

Reproducibility of indirect measurements of systolic blood pressure at ankle and toes by means of the strain gauge technique has been assessed in 20 patients with peripheral arterial disease. S.D difp between first and second determinations in double measurements lies between 4 and 6 mm Hg. The variation in gradient arm-leg was a little higher (S.D.difp about 7 mm Hg). In spite of very accurate procedure, day-to-day variation was between 7 and 10 mm Hg according to both distal pressures and arm-leg gradients. No difference in reproducibility was demonstrated, when patients with very low distal pressures and patients with moderately reduced pressures were compared. During measurements on a tilt table in several positions, it was demonstrated in 5 patients with severe peripheral arterial disease that the measured systolic toe blood pressures in the different positions deviated only a few mm Hg from the expected blood pressures, calculated from the changes in hydrostatic levels of arm and toe, and the change...