Influence of thyroxin replacement therapy on cardiovascular system in patients with primary hypothyroidism and arterial hypertension

Y. Orlov; D. Kileynikov; V. Mazur; D. Platonov; E. Mazur

Introduction: We investigated short-term influence of thyroxin replacement therapy on blood pressure (BP) and cardiovascular status in patients with first identified primary hypothyroidism (PH) and earlier diagnosed arterial hypertension (AH).

Methods: 52 patients with PH and AH were observed twice: prior to replacement therapy and after reaching euthyroid status. All patients underwent daily BP monitoring, echocardiography, and high frequency ultrasound dopplerography of nail ridge arterioles with detection of maximal systolic and end-diastolic velocity and calculation of Purselo index (PI). Results are presented as delta with 95% confidence intervals.

Results: Decrease in systolic (daytime by 8.9 (5.5–12.3), nighttime by 5.0 (2.5–7.5) mmHg) and diastolic BP (daytime by 9.4 (6.4–12.4) and nighttime by 4.5 (2.3–6.7) mmHg), interventricular septum thickness by 0.08 (0.03–0.13) cm, posterior wall thickness by 0.08 (0.04–0.12) cm, left ventricle diastolic diameter by 0.14 (0.05–0.23) cm, left ventricular mass by 24.5 (13.9–35.1) g, maximal systolic velocity by 2.5 (0.8–4.2) cm/s, and PI by 0.13 (0.06–0.20) CU were observed in patients with PH after reaching euthyroid state.

Conclusion: Compensation of thyroid state in patients with PH and AH leads to decrease in BP and improvement of ultrasound left ventricular and peripheral homodynamic parameters.

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.

**Table 1** Dynamics of cardiovascular parameters in patients with PH and AH after achievement of euthyroid status.
Parameters	Hypothyroid status	Euthyroid status
Systolic BP (daytime; mmHg)	133.4 (130.3–136.5)	124.5 (119.8–129.2)*
Systolic BP (nighttime; mmHg)	118.4 (115.4–121.4)	113.4 (110.5–116.3)*
Diastolic BP (daytime; mmHg)	85.7 (80.0–91.4)	76.3 (71.3–80.3)*
Diastolic BP (nighttime; mmHg)	74.5 (70.3–78.7)	70.0 (66.6–73.4)*
PWT (cm)	1.20 (1.13–1.27)	1.12 (1.05–1.18)*
IVST (cm)	1.12 (1.06–1.17)	1.04 (.99–1.09)*
LV DD (cm)	4.78 (4.69–4.88)	4.64 (4.56–4.72)*
LVM (g)	197.2 (181.6–212.8)	172.7 (159.8–185.6)*
Vs (cm/s)	13.1 (11.2–15.0)	10.6 (8.9–12.3)*
Vd (cm/s)	3.9 (3.0–4.8)	4.3 (3.6–5.0)
PI (CU)	0.72 (0.67–0.77)	0.59 (0.55–0.63)*
PWT, posterior wall thickness; IVST, interventricular septum thickness; LV DD, left ventricular diastolic diameter; Vs, maximal systolic velocity; Vd, end-diastolic velocity; PI, Purselo index. *P value for Δ<0.05.

Endocrine Abstracts

P1702