Cardiac sympathetic dysfunction in left ventricular hypertrophy caused by arterial hypertension and degenerative aortic stenosis

Background: To evaluate cardiac sympathetic innervation in hypertensive patients with left ventricular (LV) hypertrophy (H) and aortic stenosis (AS) submitted to transcatheter aortic valve implantation (TAVI).

Methods and results: Twenty-two hypertensive elders (82 ± 5 years) with severe AS and significant LVH (> 122 g·m^-2 in women and > 149 g·m^-2 in men) were compared with 14 patients with uncomplicated essential hypertension (HT) with similar degree of LVH and 10 controls. ¹²³I-metaiodobenzylguanidine (MIBG) and ^99mTc-tetrofosmin SPECT acquisitions were obtained to assess sympathetic innervation and LV perfusion. The innervation/perfusion mismatch score was taken as an indicator of cardiac sympathetic dysfunction. The imaging protocol was repeated 6 months after TAVI. Regional MIBG uptake was more heterogeneous in HT and AS patients than controls, and therefore, innervation/perfusion mismatch score was higher in both AS (9 ± 8) and HT (5 ± 2) than controls (1 ± 1, P < .001). On multivariate analysis, significant LVH was the major predictor of impaired LV sympathetic innervation (OR 19.45, 95% CI 1.87-201.92; P = .013). After TAVI, no differences in measures of LV sympathetic innervation were evident, although only a marginal LV mass reduction was observed (- 5.4 ± 2.4 g).

Conclusions: Cardiac sympathetic innervation is impaired in patients with LVH, either with AS or not, and is not impacted significantly by TAVI procedure.