Primary hypertension in untreated adolescents and young adults was associated with higher cardiac output compared to normotensive controls (7.8 vs 6.2 L/min; P<0.001), driven by higher heart rate.
Cross-Sectional (n=92)
What are the underlying haemodynamic circulatory changes in adolescents and young adults with untreated primary hypertension compared to normotensive controls?
In adolescents and young adults, primary hypertension is driven by increased cardiac output due to higher heart rates rather than vascular remodeling, suggesting early autonomic nervous system derangement.
Absolute Event Rate: 7.8% vs 6.2%
p-value: p=<0.001
Abstract Background Primary hypertension is increasingly prevalent in adolescents and young adults, but the underlying circulatory changes in this age group are poorly understood. We examined the haemodynamic aetiology of hypertension in untreated young people using cardiac magnetic resonance imaging. Methods Participants aged 10–30 years were prospectively recruited into an observational cross-sectional study. Hypertensive untreated participants were recruited from paediatric and adult hypertension clinics and compared with normotensive controls. Hypertension was defined using standard clinical guidelines. Cardiac magnetic resonance imaging was used to determine cardiac geometry and aortic dimensions using a 1.5 Tesla Siemens Scanner. Key haemodynamic variables were derived from left ventricular volumes acquired during a short-axis stack sequence and from post processing analysis. Blood pressure was measured at the time of cardiac magnetic resonance imaging using a validated oscillometric blood pressure monitor. Findings Results from 92 participants are presented, 41 normotensive and 51 hypertensive, similar in age and sex with higher body mass index in the hypertensive compared to normotensive group (Table 1). Mean (±SD) cardiac output was higher in hypertensive versus normotensive groups (7.8 ± 1.8 versus 6.2 ± 1.7 L/min; P 0.001), driven by higher heart rate rather than by higher stroke volume. There were no differences in systemic vascular resistance or proximal aortic pulse wave velocity. Conclusion These results suggest that in overweight/obese adolescents and young adults, higher cardiac output is a key determinant of hypertension. They implicate derangement of the autonomic nervous system rather than vascular remodelling as the earliest mechanism underlying hypertension in this age group.
Haseler et al. (Wed,) conducted a cross-sectional in Primary hypertension (n=92). Primary hypertension vs. Normotensive controls was evaluated on Cardiac output (L/min) (p=<0.001). Primary hypertension in untreated adolescents and young adults was associated with higher cardiac output compared to normotensive controls (7.8 vs 6.2 L/min; P<0.001), driven by higher heart rate.