Left ventricular myocardial impairment in subclinical hypothyroidism assessed by a new ultrasound tool: pulsed tissue Doppler.

Pulsed tissue Doppler (TD) is a new ultrasound tool that allows quantification of myocardial regional wall motion. To investigate the cardiac effects of subclinical hypothyroidism (SH), the present study assessed left ventricular (LV) myocardial regional function in SH by pulsed TD. Twenty women with SH and 20 healthy women underwent standard Doppler echocardiograms and pulsed TD, placing a sample volume at the level of posterior septum and LV mitral annulus. Myocardial systolic and diastolic velocities and time intervals were determined for both levels. Doppler-echocardiographic and TD measurements were adjusted for body surface area and heart rate. Standard Doppler showed an increases in LV preejection period, preejection period/LV ejection time ratio, and isovolumic relaxation time (IVRT) in SH. By TD analysis, myocardial precontraction time (PCT(m)), PCT(m)/myocardial contraction time ratio, and myocardial relaxation time (RT(m)) were prolonged at the level of both posterior septum and mitral annulus in SH. In the whole population, IVRT, PCT(m), and RT(m) were negatively related to FT(4), whereas IVRT, PCT(m)/myocardial contraction time ratio, and RT(m) were positively correlated to TSH. In conclusion, this study underscores the usefulness of TD to detect cardiac functional abnormalities due to stable SH, mainly by changes in myocardial time intervals in several LV segments.

Relations of pulse pressure and other components of blood pressure to preclinical echocardiographic abnormalities.

OBJECTIVE: To evaluate the extent to which pulse pressure (PP) is associated with echocardiographic abnormalities, and in particular to whether PP is related to LV hypertrophy taking into account other blood pressure (BP) components. DESIGN: Cross-sectional. SETTING: University hospital, hypertension outpatient unit. PARTICIPANTS: A total of 275 adults (mean age 47 years, range 19-69, 3% aged > or = 65) with essential hypertension. Overt coronary artery disease, valvular disease and secondary hypertension were exclusion criteria. Subjects were divided in two groups with PP < or = 50 or PP > 50 mmHg. OUTCOME MEASURES: Left ventricular (LV) mass, hypertrophy, LV systolic dysfunction. RESULTS: Prevalence of LV hypertrophy was higher in subjects with clinic PP > 50 mmHg. Subjects with PP > 50 mmHg had higher clinic and ambulatory systolic than subjects with PP < or = 50 mmHg while diastolic BP did not differ between groups. PP and systolic BP, either clinic or ambulatory, showed similar correlation to LV hypertrophy in separate logistic multivariate models. Using different methodologies, PP was not related to LV mass index or hypertrophy when the effect of its component systolic BP was taken into account. In separate analyses, PP was not significantly related to ejection fraction or midwall mechanics. CONCLUSION: Middle-aged clinically healthy hypertensives with PP > 50 mmHg had two-fold higher prevalence of LV hypertrophy than those with PP < or = 50 mmHg, which may contribute to the higher cardiovascular risk in subjects with higher PP. However, in our sample, PP was not related to LV hypertrophy independently of systolic BP, suggesting that systolic BP is the explanatory link of the relation between PP and LV hypertrophy.