Intrinsic myocardial disease in adults with GH deficiency is characterised by subclinical left ventricular longitudinal dysfunction revealed by tissue Doppler

C. Badiu; S. Mihaila; R. Mincu; R. Dulgheru; S. Jercalau; D. Vinereanu

Purpose: GH deficiency (GHD) is associated with increased cardiovascular events, however, the detailed mechanisms have not been assessed yet extensively. We set up this study in order to evaluate cardiac, arterial, and endothelial function, by conventional echo, TDI, and biomarkers (proBNP and troponin I), in GHD patients by comparison with normal individuals with similar cardiovascular risk factors profile.

Methods: Thirty GHD patients (46±14 years, 18 males) with low cardiovascular risk factors were compared with 30 matched N. Global LV systolic and diastolic functions were assessed from ejection fraction (EF), indexed cardiac output (COi), E/Vp and E/Ea ratios; longitudinal function from global longitudinal strain (GLS), and the sum of all times from the AVC to peak strain (SumTAVC); radial function from global radial strain (GRS); circumferential function from global circumferential strain (GCS); and LV torsion from peak basal (RotB) and apical rotation (RotA), and derived times (time to RotB/RotA), LV torsion (LVtor), twist rate (TR), untwist rate (UTR), time-to-peak twist (TT), and time from the AVC to UTR (AVC-UTR). Arterial function was assessed from intima-media thickening (IMT), local wave speed (LWS), and stiffness index (β); endothelial function from flow mediated dilation (FMD).

Results: GHD patients had all global, longitudinal, and circumferential systolic parameters significantly decreased, but with similar GRS (52±16 vs 52±15%) (Table). They had also higher dyssynchrony, end-diastolic LV pressure, and lower torsion with prolonged AVC-UTR. RotB correlated with GLS (r=0.4, P<0.05). Arterial and endothelial functions were similar to N.

Table 1
	EF	COi	E/Vp	E/Ea	GLS	SumTAVC	GCS	RotB	LVtor	TR
GHD	52±9	1.8±0.5	1.7±0.4	8±1	−16.8±2.5	64±5.0	−16.5±3.3	−5.2±2.5	0.18±0.05	100±32
N	68±7	2.2±0.6	1.5±0.3	6±2	−19.2±2.5	7±5	−19.4±4.0	−6.7±2.0	0.23±0.08	122±42
P value	<0.001	0.03	0.033	0.002	0.001	0.003	0.004	0.02	0.03	0.027

Conclusions: GHD patients have subclinical longitudinal and circumferential LV dysfunction, with maintained radial function; these were correlated with impaired LV torsion. Since arterial and endothelial functions were not affected, our findings suggest that patients with GHD have intrinsic myocardial disease, due probably to insufficient development of the myocardial fibers.

Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.

Funding: This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector.

Endocrine Abstracts

P340