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.

Reproducibility of aortic intima-media thickness in infants using edge-detection software and manual caliper measurements

Background

Aortic intima-media thickness measured by transabdominal ultrasound (aIMT) is an intermediate phenotype of cardiovascular risk. We aimed to (1) investigate the reproducibility of aIMT in a population-derived cohort of infants; (2) establish the distribution of aIMT in early infancy; (3) compare measurement by edge-detection software to that by manual sonographic calipers; and (4) assess the effect of individual and environmental variables on image quality.

Methods

Participants were term infants recruited to a population-derived birth cohort study. Transabdominal ultrasound was performed at six weeks of age by one of two trained operators. Thirty participants had ultrasounds performed by both operators on the same day. Data were collected on environmental (infant sleeping, presence of a sibling, use of sucrose, timing during study visit) and individual (post-conception age, weight, gender) variables. Two readers assessed image quality and measured aIMT by edge-detection software and a subset by manual sonographic calipers. Measurements were repeated by the same reader and between readers to obtain intra-observer and inter-observer reliability.

Results

Aortic IMT was measured successfully using edge-detection in 814 infants, and 290 of these infants also had aIMT measured using manual sonographic calipers. The intra-reader intra-class correlation (ICC) (n = 20) was 0.90 (95% CI 0.76, 0.96), mean difference 1.5 μm (95% LOA −39, 59). The between reader ICC using edge-detection (n = 20) was 0.92 (95% CI 0.82, 0.97) mean difference 2 μm (95% LOA −45.0, 49.0) and with manual caliper measurement (n = 290) the ICC was 0.84 (95% CI 0.80, 0.87) mean difference 5 μm (95% LOA −51.8, 61.8). Edge-detection measurements were greater than those from manual sonographic calipers (mean aIMT 618 μm (50) versus mean aIMT 563 μm (49) respectively; p < 0.001, mean difference 44 μm, 95% LOA −54, 142). With the exception of infant crying (p = 0.001), no associations were observed between individual and environmental variables and image quality.

Conclusion

In a population-derived cohort of term infants, aIMT measurement has a high level of intra and inter-reader reproducibility. Measurement of aIMT using edge-detection software gives higher inter-reader ICC than manual sonographic calipers. Image quality is not substantially affected by individual and environmental factors.

Favourable anatomy after end-to-side repair of interrupted aortic arch

OBJECTIVE

To evaluate cardiovascular outcomes in patients with aortic arch repair and their possible correlation with arch geometry.

METHODS

Ten patients who underwent end-to-side repair for aortic arch interruption (IAA), older than 10 years were compared to a cohort of 10 post coarctation (CoA) repair patients matched for age, sex and age at repair. Mean age at operation was 9.7±6.5 days. Patients underwent a resting and 24 h blood pressure measurements, exercise study, MRI, transthoracic echocardiography and vascular studies.

RESULTS

Seven patients developed hypertension, two from IAA group and five from CoA group. Nine patients (45%) had gothic arch geometry, three from IAA group and six from CoA group. Despite differences in arch geometry, both groups had normal LV mass, LV function and vascular function.

CONCLUSION

No differences in functional or morphologic outcomes could be demonstrated between the end-to-side repair of the arch by sternotomy and the conventional coarctation repair by thoracotomy. A favourable arch geometry can be achieved after the end-to-side repair of the aortic arch. In the present study, we could not correlate adverse arch geometry with any adverse cardio-vascular outcomes. After neonatal arch repair, the contributive role of aortic arch geometry to late hypertension remains uncertain.

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.