Milrinone Acts as a Vasodilator But Not an Inotrope in Children After Cardiac Surgery-Insights From Wave Intensity Analysis.

OBJECTIVES: Milrinone is an inodilator widely used in the postoperative management of children undergoing cardiac surgery. The literature supporting its inotropic effect is sparse. We sought to study the effect of milrinone on the vasculature and its effects on the ventricular function using wave intensity analysis. We also intended to evaluate the feasibility of using wave intensity analysis by the bedside. DESIGN: prospective single-center observational study. SETTING: PICU of a tertiary children's hospital. PATIENTS: Children (< 18 yr) admitted to PICU following cardiac surgery who required to be commenced on a milrinone infusion. INTERVENTIONS: Echocardiography and Doppler ultrasound assessments for wave intensity analysis were performed prior to commencing milrinone and 4-6 hours after milrinone infusion. MEASUREMENTS AND MAIN RESULTS: Wave intensity analysis was successfully performed and analyzed in 15 of 16 patients (94%). We identified three waves-a forward compression wave, backward compression wave, and forward decompression wave. The waves were described with their cumulative intensity and wave-related pressure change. There was a 26% reduction in backward compression wave cumulative intensity following the introduction of milrinone. Other variables (backward compression wave cumulative intensity/forward compression wave cumulative intensity ratio, backward compression wave wave-related pressure change, backward compression wave wave-related pressure change/forward compression wave wave-related pressure change ratio) consistent with vasodilation also decreased after milrinone. It also decreased the vascular wavespeed by 7.1% and increased the distensibility of the vessels by 14.6%. However, it did not increase forward compression wave cumulative intensity, a variable indicating the systolic force generated by the ventricle. Forward decompression wave cumulative intensity indicating ventricular early diastolic relaxation also did not change. CONCLUSIONS: In a cohort of children recovering in PICU after having undergone cardiac surgery, we found that milrinone acted as a vasodilator but did not demonstrate an improvement in the contractility or an improved relaxation of the left ventricle as assessed by wave intensity analysis. We were able to demonstrate the feasibility and utility of wave intensity analysis to further understand ventriculo-vascular interactions in an intensive care setting.

A Cross-Sectional Study of the Prevalence of Exercise-Induced Hypertension in Childhood Following Repair of Coarctation of the Aorta.

BACKGROUND: Exercise-testing may be a more tolerable method of detecting hypertension in children after coarctation repair compared to gold-standard 24-hour ambulatory blood pressure (BP) monitoring (ABPM). This study aims to determine the prevalence of exercise-induced hypertension and end-organ damage in children after coarctation repair, and the effectiveness of exercise-testing compared to 24-hour ABPM in this population. METHODS: Exercise-testing (Bruce protocol), transthoracic echocardiogram, 24-hour ABPM, and pulse wave velocity were performed in 41 patients aged 8 to 18 years with previous coarctation repair. Median age at repair was 13 days. Exercise-testing data were compared to healthy paediatric controls. Hypertension was defined as BP >95th percentile on 24-hour ABPM compared to normalised data, and systolic BP (SBP) arbitrarily >200mmHg on exercise-testing. RESULTS: After 13±3years, 39% (14/36) were hypertensive on 24-hour ABPM and 12% (5/41) on exercise-testing. Coarctation patients had a higher peak exercise SBP and reduced endurance compared to controls (164±26mmHg vs. 148±19mmHg, p=0.003; and 13.0±1.7mins vs. 14.2±2.4mins, p=0.007; respectively). All patients with a peak exercise SBP >190mmHg were hypertensive on 24-hour ABPM. Pulse wave velocity was higher in hypertensive patients on exercise-testing and 24-hour ABPM compared to normotensive patients (p=0.004 and p=0.06; respectively). CONCLUSIONS: Exercise-testing may be a useful tool to detect hypertension in children and young adults after coarctation repair, particularly in those who do not tolerate 24-hour ABPM. Normative peak exercise BP data for age should be obtained to improve the accuracy of exercise-testing in detecting hypertension.

Elevated Blood Pressure with Reduced Left Ventricular and Aortic Dimensions in Adolescents Born Extremely Preterm.

OBJECTIVE: To evaluate the long-term cardiovascular effects of extremely preterm birth in a cohort of adolescents followed prospectively, who were largely free from intrauterine growth restriction. STUDY DESIGN: Central blood pressures, aortic and cardiac dimensions, left ventricle (LV) function, pulse wave velocity, augmentation index, and microvascular reactive hyperemia were measured in 18-year-old subjects born extremely preterm at <28 weeks' gestation (n = 109) and term-born controls (n = 81). RESULTS: Compared with controls, preterm adolescents had higher systolic (124 ± 13 vs 118 ± 10 mm Hg, P = .002) and diastolic (72 ± 8 vs 67 ± 7 mm Hg, P < .001) blood pressures, but lower ascending aortic z-scores (0.13 ± 0.89 vs 0.42 ± 0.78, P = .02), LV diastolic (48.5 ± 4 vs 50.3 ± 4.5 mm, P = .007) and systolic (30.2 ± 3.5 vs 31.9 ± 4.0 mm, P = .003) diameters, and a reduced LV mass (130 ± 34 vs 145 ± 41 g, P = .01) and mass index (75 ± 14 vs 81 ± 16 g/m(2), P = .02). However, LV relative wall thickness, LV function, pulse wave velocity, augmentation index, and microvascular reactive hyperemia were similar. Within the ex-preterm group, there were no significant relationships between birthweight z-scores and any cardiovascular measures, once the latter were adjusted for current body size. CONCLUSIONS: Extremely preterm birth had relatively minor cardiovascular effects in late-adolescence, with increased blood pressures, decreased LV, and aortic size, but preserved LV function, macrovascular properties, and microvascular function. In utero growth was not independently related to cardiovascular function within the ex-preterm cohort.

Kawasaki disease and cardiovascular risk: a comprehensive review of subclinical vascular changes in the longer term.

UNLABELLED: Studies of subclinical vascular changes post-Kawasaki disease indicate that, in general, individuals with a history of coronary artery aneurysms have increased carotid intima-media thickness, evidence of endothelial dysfunction, and increased arterial stiffness, possibly indicative of heightened cardiovascular risk. The results are less consistent for low-risk groups. CONCLUSION: Until data are available from larger prospective studies, it is prudent to advise families of individuals with a history of Kawasaki disease to minimise traditional modifiable cardiovascular risk factors.

Superiority of a Representative MRI Flow Waveform over Doppler Ultrasound for Aortic Wave Reflection Assessment in Children and Adolescents With/Without a History of Heart Disease.

Wave separation analysis (WSA) reveals the impact of forward- and backward-running waves on the arterial pressure pulse, but the calculations require a flow waveform. This study investigated (1) the variability of the ascending aortic flow waveform in children and adolescents with/without a childhood heart disease history (CHD); (2) the accuracy of WSA obtained with a representative flow waveform (RepFlow), compared with the triangulation method and published ultrasound-derived adult representative flow; (3) the impact of limitations in Doppler ultrasound on WSA; and (4) generalizability of results to adults with a history of CHD. Phase contrast MRI was performed in youth without (n = 45, Group 1, 10-19 years) and with CHD (n = 79, Group 2, 7-18 years), and adults with CHD history (n = 29, Group 3, 19-59 years). Segmented aortic cross-sectional area was used as a surrogate for the central pressure waveform in WSA. A subject-specific virtual Doppler ultrasound was performed on MRI data by extracting velocities from a sample volume. Time/amplitude-normalized ascending aortic flow waveforms were highly consistent amongst all groups. WSA with RepFlow therefore yielded errors < 10% in all groups for reflected wave magnitude and return time. Absolute errors were typically 1.5-3 times greater with other methods, including subject-specific (best-case/virtual) Doppler ultrasound, for which velocity profile skewing introduced waveform errors. Our data suggest that RepFlow is the optimal approach for pressure-only WSA in children and adolescents with/without CHD, as well as adults with CHD history, and may even be more accurate than subject-specific Doppler ultrasound in the ascending aorta.

Safety and feasibility of adjunct autologous cord blood stem cell therapy during the Norwood heart operation.

BACKGROUND: We conducted this phase I, open-label safety and feasibility trial of autologous cord blood (CB) stem cell (CBSC) therapy via a novel blood cardioplegia-based intracoronary infusion technique during the Norwood procedure in neonates with an antenatal diagnosis of hypoplastic left heart syndrome (HLHS). CBSC therapy may support early cardiac remodeling with enhancement of right ventricle (RV) function during the critical interstage period. METHODS: Clinical grade CB mononucleated cells (CBMNCs) were processed to NetCord-FACT International Standards. To maximize yield, CBSCs were not isolated from CBMNCs. CBMNCs were stored at 4 °C (no cryopreservation) for use within 3 days and delivered after each cardioplegia dose (4 × 15 mL). RESULTS: Of 16 patients with antenatal diagnosis, 13 were recruited; of these 13 patients, 3 were not treated due to placental abruption (n = 1) or conditions delaying the Norwood for >4 days (n = 2) and 10 received 644.9 ± 134 × 106 CBMNCs, representing 1.5 ± 1.1 × 106 (CD34+) CBSCs. Interstage mortality was 30% (n = 3; on days 7, 25, and 62). None of the 36 serious adverse events (53% linked to 3 deaths) were related to CBMNC therapy. Cardiac magnetic resonance imaging before stage 2 (n = 5) found an RV mass index comparable to that in an exact-matched historical cohort (n = 22), with a mean RV ejection fraction of 66.2 ± 4.5% and mean indexed stroke volume of 47.4 ± 6.2 mL/m2 versus 53.5 ± 11.6% and 37.2 ± 10.3 mL/m2, respectively. All 7 survivors completed stage 2 and are alive with normal RV function (6 with ≤mild and 1 with moderate tricuspid regurgitation). CONCLUSIONS: This trial demonstrated that autologous CBMNCs delivered in large numbers without prior cryopreservation via a novel intracoronary infusion technique at cardioplegic arrest during Norwood palliation on days 2 to 3 of life is feasible and safe.

Galactose treatment of a PGM1 patient presenting with restrictive cardiomyopathy.

We report a patient diagnosed with PGM1-CDG at 11 years of age after two biallelic likely pathogenic variants in PGM1 were found on research genomic sequencing. To our knowledge, he is the first patient with PGM1-CDG to be reported with a restrictive cardiomyopathy. Other clinical manifestations included cleft palate, asymptomatic elevated transaminases, intellectual disability and myopathy resulting in exercise intolerance. He was trialed on oral galactose therapy in increasing doses for 18 weeks to assess if there was any biochemical and clinical benefit. His galactose was continued for a further 9 months beyond the initial galactose treatment period due to improvements in exercise tolerance and myopathy. Treatment with galactose demonstrated an improvement in liver function and myopathy with improved exercise tolerance. Treatment with galactose for 15 months did not change heart function and exercise stress test results were stable.

Measurement, Analysis and Interpretation of Pressure/Flow Waves in Blood Vessels.

The optimal performance of the cardiovascular system, as well as the break-down of this performance with disease, both involve complex biomechanical interactions between the heart, conduit vascular networks and microvascular beds. 'Wave analysis' refers to a group of techniques that provide valuable insight into these interactions by scrutinizing the shape of blood pressure and flow/velocity waveforms. The aim of this review paper is to provide a comprehensive introduction to wave analysis, with a focus on key concepts and practical application rather than mathematical derivations. We begin with an overview of invasive and non-invasive measurement techniques that can be used to obtain the signals required for wave analysis. We then review the most widely used wave analysis techniques-pulse wave analysis, wave separation and wave intensity analysis-and associated methods for estimating local wave speed or characteristic impedance that are required for decomposing waveforms into forward and backward wave components. This is followed by a discussion of the biomechanical phenomena that generate waves and the processes that modulate wave amplitude, both of which are critical for interpreting measured wave patterns. Finally, we provide a brief update on several emerging techniques/concepts in the wave analysis field, namely wave potential and the reservoir-excess pressure approach.

Comparison of invasive and non-invasive aortic wave intensity and wave power analyses in sheep.

OBJECTIVE: Wave intensity (WI) and wave power (WP) analyses are powerful approaches for assessing ventricular-vascular interactions and arterial dynamics using invasive and non-invasive methods. However, in vivo comparison of these methods for large arteries is lacking. This study assessed agreement, correlation and relative changes in wave size in invasive and non-invasive aortic WI/WP analyses, and associated sources of error. APPROACH: The proximal descending thoracic aorta (DTA) of nine wethers was instrumented with a micromanometer and perivascular transit-time flow probe to measure high-fidelity blood pressure (P) and flow (Q) for invasive WI/WP analyses at baseline and during haemodynamic perturbations produced by cardiac pacing, distal DTA constriction and dobutamine-induced inotropic stimulation. In 212 experimental runs, concurrent echocardiographic DTA diameter and velocity (U) data were acquired for non-invasive WI/WP analyses, with measurement of forward compression wave (FCW), backward compression wave (BCW) and forward decompression wave (FDW) cumulative intensity (CI), cumulative power (CP) and wave-related pressure changes (ΔP). MAIN RESULTS: Although agreement between invasive and non-invasive FCW, BCW and FDW CI/CP measures was variable (bias -84% to +7%), correlation was good (R = 0.66-0.84), with lower bias and higher correlation for ΔP variables and similar relative changes in FCW and BCW CI/ΔP during haemodynamic perturbations. Main error sources were overestimation of invasive U due to assumed fixed vessel diameter, inaccuracies in non-invasive Q, and non-invasive underestimation of peak P/U and Q rates of change. SIGNIFICANCE: Despite variable agreement, non-invasive CI/CP indices correlate well with invasive measurements, and detect relative changes in major waves induced by haemodynamic perturbations.

Reduced Aortic Distensibility is Associated With Higher Aorto-Carotid Wave Transmission and Central Aortic Systolic Pressure in Young Adults After Coarctation Repair.

Background The long-term prognosis of patients with repaired aortic coarctation is characterized by high rates of cardiovascular and cerebrovascular disease related to hypertension, the basis of which remains unclear. To define potential underlying mechanisms, we investigated aortic and carotid arterial biomechanics and wave dynamics, and determinants of aortic systolic blood pressure, in young adults after coarctation repair. Methods and Results Aortic arch and carotid biomechanics, wave intensity and wave power, and central aortic blood pressure, were derived from echocardiography and brachial blood pressure in 43 young adults after coarctation repair and 42 controls. Coarctation subjects had higher brachial and central systolic blood pressure ( P=0.04), while aortic compliance was lower and characteristic impedance (Zc) higher. Although carotid intima-media thickness was higher ( P<0.001), carotid biomechanics were no different. Carotid forward compression wave power was higher and was negatively correlated with aortic compliance ( R2=0.42, P<0.001) and distensibility ( R2=0.37, P=0.001) in coarctation subjects. Aortic wave power and wave reflection indices were no different in control and coarctation patients, but coarctation patients with elevated aortic Zc had greater aorto-carotid transmission of forward compression wave power ( P=0.006). Aortic distensibility was the only independent predictor of central aortic systolic blood pressure on multivariable analysis. Conclusions Young adults following coarctation repair had a less compliant aorta, but no change in carotid biomechanics. Reduced aortic distensibility was related to greater transmission of aortic forward wave energy into the carotid artery and higher central aortic systolic blood pressure. These findings suggest that reduced aortic distensibility may contribute to later cardiovascular and cerebrovascular disease after coarctation repair.

Increased aortic wave reflection contributes to higher systolic blood pressure in adolescents born preterm.

OBJECTIVE: To evaluate the wave reflection characteristics in the aortic arch and common carotid artery of ex-preterm adolescents and assess their relationship to central blood pressure in a cohort followed prospectively since birth. METHODS: Central blood pressures, pulse wave velocity, augmentation index, microvascular reactive hyperemia, arterial distensibility, compliance and stiffness index, and also aortic and carotid wave intensity were measured in 18-year-olds born extremely preterm at below 28 weeks' gestation (n = 76) and term-born controls (n = 42). RESULTS: Compared with controls, ex-preterm adolescents had higher central systolic (111 ±â€Š11 vs. 105 ±â€Š10 mmHg; P < 0.001) and diastolic blood pressures (73 ±â€Š7 vs. 67 ±â€Š7 mmHg; P < 0.001). Although conventional measures of arterial function and biomechanics such as pulse wave velocity and augmentation index were no different between groups, wave intensity analysis revealed elevated backward compression wave area (-0.39 ±â€Š0.21 vs. -0.29 ±â€Š0.17 W/m/s × 10; P = 0.03), backward compression wave pressure change (9.0 ±â€Š3.5 vs. 6.6 ±â€Š2.5 mmHg; P = 0.001) and reflection index (0.44 ±â€Š0.15 vs. 0.32 ±â€Š0.08; P < 0.001) in the aorta of ex-preterm adolescents compared with controls. These changes were less pronounced in the carotid artery. On multivariable analysis, forward and backward compression wave areas were the only biomechanical variables associated with central systolic pressure. CONCLUSIONS: Ex-preterm adolescents demonstrate elevated wave reflection indices in the aortic arch, which correlate with central systolic pressure. Wave intensity analysis may provide a sensitive novel marker of evolving vascular dysfunction in ex-preterm survivors.

Beyond the aorta: partial transmission of reflected waves from aortic coarctation into supra-aortic branches modulates cerebral hemodynamics and left ventricular load.

Wave reflection from the site of aortic coarctation produces a reflected backward compression wave (BCW) that raises left ventricular (LV) afterload. However, not all reflected wave power will propagate back to the LV. This study investigated the hypothesis that the BCW is partially transmitted into supra-aortic vessels as a forward wave and explored the consequences of this phenomenon for cerebral and LV haemodynamic load. In eight sheep, high fidelity pressure and flow were measured in the aortic trunk (AoT) and brachiocephalic trunk (BCT, the single supra-aortic vessel present in sheep) at baseline and during two levels of proximal descending aortic constriction. Wave power analysis showed that aortic constriction produced not only a BCW in the AoT, but also a second forward compression wave ([Formula: see text] in the BCT that augmented pressure and flow after the initial forward compression wave ([Formula: see text]. Mathematical analysis and a one-dimensional model of the human systemic arteries and aortic coarctation suggested that the relative transmission of waves into supra-aortic vessels versus the aorta was determined by the relative admittances of these vessels. Reducing supra-aortic admittance (1) increased pressure and flow pulsatility in cerebral arteries, (2) produced carotid and middle cerebral arterial flow waveforms with an older adult phenotype, (3) promoted transmission of reflected wave power towards the LV and (4) substantially increased mid- to late-systolic myocardial stress, which may promote LV hypertrophy. These findings suggest that wave transmission into supra-aortic branches has an important impact on both cerebral hemodynamics and LV load in aortic coarctation.

Robust and practical non-invasive estimation of local arterial wave speed and mean blood velocity waveforms.

OBJECTIVE: Local arterial wave speed, a surrogate of vessel stiffness, can be estimated via the pressure-velocity (PU) and diameter-velocity (ln(D)U) loop methods. These assume negligible early-systolic reflected waves (RWes) and require measurement of cross-sectionally averaged velocity (U mean), which is related to volumetric blood flow. However, RWes may not always be negligible and Doppler ultrasound typically provides maximum velocity waveforms or estimates of mean velocity subject to various errors (U raw). This study investigates how these issues affect wave speed estimation and explores more robust methods for obtaining local wave speed and U mean. APPROACH: Using aortic phase-contrast MRI (PCMRI, n = 34) and a simulated virtual cohort (n = 3325), we assessed errors in calculated wave speed caused by RWes and use of U raw rather than true U mean. By combining PU raw and ln(D)U raw loop wave speed values, (i) a corrected wave speed (ln(D)P), insensitive to RWes and velocity errors, was derived; and (ii) a novel method for estimating U mean from U raw was proposed (where U raw can be any scaled version of U mean). MAIN RESULTS: Proof-of-principle was established via PCMRI data and in the ascending aorta, carotid, brachial and femoral arteries of the virtual cohort, with acceptably low wave speed and U mean errors obtained even when local pressure was estimated from diameter and mean/diastolic brachial pressures. SIGNIFICANCE: Given a locally measured diameter waveform and brachial cuff pressures, (i) the velocity- and RWes-independent ln(D)P method can be applied non-invasively and is likely more robust than ln(D)U and PU loop methods; and (ii) U mean can be estimated from routinely-acquired U raw.

Risk factors and clinical features of acute pulmonary embolism in children from the community.

BACKGROUND AND AIMS: Current clinical decision rules for pulmonary embolism are based on adult populations and have not been validated in children. The objective was to identify and evaluate clinical features for a first lifetime episode of pulmonary embolism in children presenting to the emergency department. MATERIALS AND METHODS: We present a case-control study of children (≤18years) presenting to the emergency department of the Royal Children's Hospital, Melbourne between November 2007 and February 2015. Children with radiologically proven pulmonary embolism formed the case group, whilst children in whom there was a clinical suspicion of pulmonary embolism but negative diagnostic imaging formed the control group. Charts, electronic medical and imaging records of both cases and controls were reviewed and analysed. RESULTS: There were a total of 50 patients in this study (11 cases and 39 controls). Current or recent (within three months) use of the oral contraceptive pill was the most significant risk factor in our study (odds ratio 14.667, 95% confidence interval 3.001-71.678, P<0.001). Most other features failed to discriminate between cases and controls, although there was a trend towards increased heart rate in cases. CONCLUSIONS: Pulmonary embolism is perhaps the most common presenting spontaneous venous thromboembolism in the community and teenage girls on the oral contraceptive pill are most at-risk amongst children. The clinical signs and symptoms are often non-specific. Additional larger studies are required to determine the significance and magnitude of potential clinical predictors identified in this study. This may lead to derivation of a paediatric-specific pre-test probability tool.

High Prevalence of Hypertension and End-Organ Damage Late After Coarctation Repair in Normal Arches.

BACKGROUND: To (1) determine the prevalence of hypertension late after coarctation repair in patients with normal-sized transverse arches, and (2) evaluate the potential for end-organ damage related to hypertension after coarctation repair. There are no studies specifically investigating end-organ damage and hypertension after coarctation repair using noninvasive techniques. METHODS: Eighty-two patients aged 10 years or greater with a coarctation repair and a normal-sized arch operated on between 1978 and 2010, underwent a transthoracic echocardiogram, 24-hour blood pressure (BP) monitoring, and retinal imaging. Median age at repair was 1 year (interquartile range, 0 to 6); 45% (37 of 82) were operated in the first year of life. RESULTS: After a follow-up of 24 ± 7 years, 27% (22 of 82) and 50% (41 of 82) suffered resting hypertension and resting prehypertension, respectively. On 24-hour BP monitoring, 61% (49 of 80) and 21% (17 of 80) suffered hypertension and prehypertension, respectively. Arch reobstruction (echo gradient > 25 mm Hg) was present in only 15% (12 of 82), and in only 15% (7 of 47) with 24-hour hypertension. Resting hypertension was associated with a smaller central retinal artery equivalent (average width of arterioles) and central retinal vein equivalent (average width of venules) (p = 0.0006 and p = 0.003, respectively). Left ventricular hypertrophy on echocardiography was present in 63% (31 of 49) with 24-hour hypertension compared with only 42% (13 of 31) with normal 24-hour BP (p = 0.06). CONCLUSIONS: There is a high rate of hypertension late after coarctation repair, even in patients with unobstructed arches. The presence of retinal imaging abnormalities and left ventricular hypertrophy signals the presence of end-organ damage in this young adult population. Regular follow-up with 24-hour BP monitoring is warranted.

Ross procedure in children: 17-year experience at a single institution.

BACKGROUND: The Ross procedure in children carries substantial mortality and reoperation rate. Aortic root dilatation is of concern. To prevent dilatation of the neoaortic root, but permit normal growth, we began to apply an absorbable poly-(p-dioxanone)-filaments (PDS) band at the sino-tubular (ST)-junction. METHODS AND RESULTS: All children (n=100) who underwent Ross procedure during 1995-2012 were studied. Mean age at operation was 8.6±6.1 years (median 8.3 years, range 3 days to 18 years); 19 patients were younger than 1 year of age. The root replacement (n=91, Ross-Konno procedure in 29 patients), root inclusion (n=6), and subcoronary implantation (n=3) techniques were used. Operative mortality was 6% (6/100, 4 neonates, 2 infants). Age of <1-year at time of operation was a risk factor for early death (P<0.001). Mean follow-up time was 7.0±4.8 years (median 7.4 years, range 5 days to 16 years). Late mortality was 4.3% (4/94). Freedom from moderate or greater neoaortic valve insufficiency (AI) at 5 and 10 years was 89% and 83%, respectively. Freedom from neoaortic valve reoperation at 5 and 10 years was 96% and 86%, respectively. Aortic dilatation to Z-score >4 was greatest at the ST-junction (23%, 11/48) compared to the aortic annulus (17%, 11/66) and sinuses (14%, 7/50). Since 2001, a PDS band was placed around the ST-junction in 19 patients. Survivors with the PDS band had less AI (0 versus 20%, P=0.043) compared to survivors (n=35) without the PDS at 4.1±3 years. CONCLUSIONS: The Ross procedure in children can be performed with acceptable results. Children younger than 1 year of age have higher mortality, but not an increased autograft reoperation rate. Stabilization of the ST-junction may reduce AI.

Twenty-four-hour ambulatory blood pressure monitoring detects a high prevalence of hypertension late after coarctation repair in patients with hypoplastic arches.

OBJECTIVES: To determine by 24-hour blood pressure monitoring the risk of hypertension late after coarctation repair in patients with arch hypoplasia. METHODS: Sixty-two of 116 consecutive patients (age, ≥10 years) who had coarctation repair and were quoted subjectively by the surgeon or the cardiologist to have arch hypoplasia at the time of the repair underwent a transthoracic echocardiogram and 24-hour blood pressure monitoring. Median age at repair was 11 days (range, 6-48 days). Mean preoperative z score of the proximal transverse arch was -2.43 ± 0.46. Eight patients had a repair via sternotomy (6 end-to-side anastomoses, 2 patch repairs) and 54 had a conventional repair via thoracotomy. RESULTS: After a follow-up of 18 ± 5 years, 27% of the patients (17/62) had resting hypertension and 60% (37/62) had abnormal ambulatory blood pressure. Sensitivity of high resting blood pressure in detecting an abnormal 24-hour ambulatory blood pressure was 41%. Twenty patients had arch obstruction at last follow-up. Eighteen of them (90%) had abnormal ambulatory blood pressure. None of the patients operated on with end-to-side repair via sternotomy had reobstruction compared with 33% (18/54) of those repaired via thoracotomy. CONCLUSIONS: Patients with a hypoplastic arch operated via thoracotomy have an alarming prevalence of hypertension. Regular follow-up with 24-hour ambulatory blood pressure monitoring is warranted, especially in patients who have had a smaller aortic arch at the time of the initial operation.

Moderately hypoplastic arches: do they reliably grow into adulthood after conventional coarctation repair?

UNLABELLED: To determine whether conventional coarctation repair results in sustained growth of hypoplastic transverse arches, we examined the follow-up of 20 patients operated through a thoracotomy between 1990 and 1995 who had available serial echocardiographic examinations. Mean age at operation was 8.6+/-5.7 days. In the distal transverse arch, maximum change was observed in the early postoperative period and sustained growth was observed thereafter. At last follow-up, no patients had Z-scores of less than -2. In contrast, only minimal growth occurred in the proximal transverse arch (mean Z-score diameter before and after repair: -1.87+/-0.12 vs. -1.66+/-0.09; P=0.05) in the postoperative period. At last follow-up, seven patients (35%) kept a diameter Z-score of less than -2, and 5 of them had a gradient of 15 mmHg (P=0.01). No correlation was found between the size of the proximal arch at last follow-up and its size before repair or technique used. CONCLUSION: Patients with moderately hypoplastic arch treated by conventional coarctation repair have adequate growth of the distal arch demonstrated at long-term follow-up, but one-third of them keep a small proximal arch. This subset of patients is at risk of developing hypertension and may warrant further investigation.