Increased pulse wave velocity and blood pressure in children who have undergone cardiac transplantation.

BACKGROUND: Arterial hypertension and premature coronary artery disease are poorly understood complications of cardiac transplantation in children. Arterial stiffness is associated with cardiovascular risk in adults. Pulse wave velocity (PWV) may be used as a surrogate for arterial rigidity. In this study we investigate PWV in children after cardiac transplantation.

METHODS: Sitting blood pressure was measured in 22 children (>6 months after transplantation) and 95 controls and PWV was measured using the SphygmoCor device by high-fidelity applanation tonometry at the carotid, radial and femoral arteries.

RESULTS: The transplant group was significantly older than the control group (13.4 years vs 11.1 years; p = 0.006), but there was no significant height or weight difference. The diastolic (but not systolic) pressure was significantly higher in the transplant group (75 mm Hg vs 65 mm Hg; p = 0.003). Aortic (carotid/femoral) PWV was significantly associated with age, height, weight (in the control group only) and systolic blood pressure according to univariate analysis, whereas brachial (carotid/radial) PWV was unrelated to these. According to multivariate analysis, height accounted best for all relationships with aortic PWV, and age and weight for brachial PWV. Using multivariate analysis, PWV was significantly higher in the cardiac transplant group for brachial (7.6 m/s vs 6.6 m/s; p < 0.01) and aortic (5.3 m/s vs 4.7 m/s; p < 0.001) measurements. The relation between length of time since transplantation and aortic PWV was statistically significant (p < 0.01).

CONCLUSIONS: Arterial rigidity is increased in children after cardiac transplantation. An improved understanding of blood pressure and arterial stiffness may help inform the choice of blood pressure medication in these patients.