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Background: Prehypertension predicts established hypertension. In this study, the aim was to analyze left ventricular (LV) mechanics in borderline prehypertensive (pre-HT) and hypertensive (HT) subjects through two-dimensional (2D)-strain echocardiography and then evaluate possible relations between cardiac parameters and insulin metabolism (homeostasis model assessment of insulin resistance (HOMA(IR))., Methods: Seventy-four consecutive newly diagnosed, untreated HT were divided, on the basis of their office blood pressure (BP) measurements, confirmed by ambulatory BP monitoring (ABPM), in 41 borderline pre-HT (ABPM: 122.5 +/- 6.7/76.2 +/- 5.2 mm Hg) and 33 never-treated mild HT (ABPM: 138.3 +/- 7.3/87.6 +/- 7.1 mm Hg). Thirty-three healthy normotensive (NT) controls (ABPM: 114.8 +/- 6.3/73.1 +/- 6.1 mm Hg) (P < 0.0001) were also studied (NT). All subjects performed 2D color Doppler and pulsed-wave tissue Doppler imaging (PW-TDI)., Results: Left ventricular mass (LVM) was significantly higher in pre-HT (39.2 +/- 8.7 g/m(2.7)) and in HT (43.6 +/- 8.5 g/m(2.7)) compared with NT (30.9 +/- 7.4 g/m(2.7)) (P < 0.0001). A mild LV diastolic dysfunction was found both with Doppler mitral flow velocity and PW-TDI at mitral annulus level analysis. Longitudinal 2D strain in pre-HT (-18.9% +/- 3.4) and in HT (-18.0% +/- 3.3) was significantly lower than in NT (-23.9% +/- 3.0) (P < 0.002). These LV abnormalities were associated with systolic ABPM, LVM, and HOMA(IR)., Conclusions: Early abnormalities of LV longitudinal systolic deformation were found both in pre-HT and HT, together with a mild LV diastolic dysfunction. In both groups this early cardiac systolic and diastolic dysfunction is associated to insulin resistance, systolic pressure load, and cardiac remodeling.

The aim of the present study was to evaluate cardiac function and texture in patients with subclinical hypothyroidism (sHT) both by conventional and new ultrasonic intramyocardial tissue techniques. sHT was characterized by normal serum free tetraiodotironine and free triiodotironine levels and slightly increased serum TSH level. Twenty-four patients affected by sHT and 24 sex- and age-matched healthy volunteers were studied. All subjects were submitted to conventional two-dimensional (2D)-color Doppler echocardiography, pulsed wave tissue Doppler imaging (PWTDI) for the analysis of the diastolic function, color Doppler myocardial imaging (CDMI) for the analysis of regional strain and strain-rate and integrated backscatter (IBS) for the evaluation of intrinsic contractility and tissue characterization. The results of the present study were: (a) the detection in sHT subjects of a lower cyclic variation index (CVI) indicating an altered myocardial intrinsic contractility; (b) a higher ultrasonic myocardial reflectivity indicating an altered myocardial texture; (c) the detection of lower systolic strain and strain-rate indicating an alteration of myocardial regional deformability; (d) an initial impairment of left ventricular diastolic function indicated by a decrease of peak E mitral flow velocity and an increase of peak A mitral flow velocity. All parameters studied with conventional 2D-echo in sHT patients were comparable with controls, except for a mild alteration in diastolic function. A significant correlation among systo-diastolic modifications detected by CDMI and IBS and serum TSH levels were found. The CVI at septum, the PWDTI S-peak wave and the systolic strain at septum were inversely related to the serum TSH levels. In conclusion, the new intramyocardial ultrasonic techniques confirm and extend the previous knowledge on the effect of the sHT on the heart, allowing the detection of early ultrastructural and regional functional systolic and diastolic abnormalities.

The mitral annulus velocities of Doppler transmitral flow and pulsed-wave tissue Doppler imaging (TDI) were sampled by echocardiography for the assessment of left ventricular (LV) diastolic function in 118 never-treated essential hypertensive patients with normal systolic function and compared with those of 59 normotensive healthy subjects matched for age and sex. A selected group (n = 26) of the hypertensive study population was observed after 1 year of pharmacologic antihypertensive treatment to determine the behavior of TDI parameters in relation to eventual regression of LV hypertrophy (LVH). We found that the TDI early myocardial diastolic wave (E(m)) was significantly lower both in concentric and eccentric LVH. In addition, TDI late myocardial diastolic wave (A(m)) was significantly higher in concentric remodeling and concentric and eccentric hypertrophy. The TDI E(m)/A(m) ratio was significantly lower in all geometric remodeling subgroups. The E/A ratio Doppler transmitral flow velocity measured showed that of the 118 patients, only 32 (25%) could really be discriminated from normal, whereas individual analysis for TDI E(m)/A(m) at the mitral annulus septal level showed that of 118 patients 108 (91%) could be discriminated from normal P < .001). The LV mass was significantly less after 1 year of treatment (LVH regression), and TDI parameters showed a trend toward normalization, in particular of TDI E(m)/A(m) at the annular septal level. Pulsed-wave TDI analysis could enable not only the early assessment of whether a patient is still in an adaptive or compensatory phase before transition to irreversible damage (pathologic phase) but also the detection of precocious LV global diastolic dysfunction. With regard to this, more extensive randomized studies are needed to evaluate the effect of different pharmacologic treatments (calcium antagonists, beta-blockers, angiotensin I and II inhibitors) on TDI parameters.

Aim: To investigate the effect of abciximab on microvascular integrity and left ventricular (LV) functional recovery in patients with acute myocardial infarction (MI) treated by primary coronary angioplasty (PTCA)., Methods and Results: Thirty-one patients (27 males; age 39-76 years) with first, acute MI (<6 h after onset) were randomized to receive either abciximab+primary PTCA (n=17) or primary PTCA alone (n=14). Baseline characteristics of the two groups were similar. Myocardial reperfusion was studied shortly after PTCA by corrected TIMI frame count (cTFC) and intracoronary myocardial contrast echocardiography (MCE), after 48 h by intravenous MCE using intermittent, harmonic power Doppler, and after 1 month by intravenous MCE and 99 mTc-tetrofosmin SPECT. The patients treated with abciximab showed a shorter cTFC (23+/-4 vs 30+/-9 frames; P<0.05), a more preserved microvascular integrity shortly after PTCA (77% vs 55%; P<0.01), after 48 h (86% vs 50%; P<0.005) and at 1-month follow-up (86% vs 54% by MCE, P<0.001, and 68% vs 60% by SPECT, P<0.005) than patients treated with PTCA alone. Abciximab patients also showed a better recovery of LV function, as demonstrated by greater reduction in wall motion score index (1.4+/-0.3 vs 1.5+/-0.2; P<0.05) and increase in LV ejection fraction (53+/-7% vs 48+/-5%; P<0.001)., Conclusions: Abciximab improves microvascular perfusion and LV functional recovery in primary PTCA.

Aims: The aims of the present study were: (a) to demonstrate whether quantitative myocardial contrast echocardiography can detect the increase in coronary flow induced by dipyridamole infusion vasodilation through the myocardial opacification due to the transit of microbubbles, both at rest and after dipyridamole induced vasodilation; (b) to explore the coronary microcirculatory function before and after dipyridamole in two different models: asymptomatic and relatively young hypertensive patients with a mild degree of left ventricular hypertrophy, and healthy controls., Methods and Results: Two groups of strictly age-matched males were studied (case-control study): 10, relatively young and asymptomatic essential hypertensive patients with a mild degree of left ventricular hypertrophy with a normal left ventricular function, and 10 healthy controls. The main findings were: the microbubbles' appearance area was significantly lower in hypertensive patients than in controls (P<0.05) because of a significantly lower time to peak. The peak intensity at rest was higher in hypertensives than in controls (P<0.05); but the per cent increase after vasodilatory stimulus was significantly higher in controls (+71% in controls vs +31% in hypertensives; P<0.05). The microbubbles' disappearance area was comparable in both groups at rest; the per cent increase of this parameter after dipyridamole was significantly higher in controls (+124%) than in hypertensives (+90%) (P<0.05). The results achieved in this study documented that the coronary microcirculation in hypertensive patients presenting a mild degree of left ventricular hypertrophy, explored with quantitative myocardial contrast echocardiography, showed a different behaviour in comparison with controls, in the vasodilatory response to dipyridamole., Conclusion: The coronary microcirculation in hypertensives showed a reduced vasodilation capacity of the resistance arterioles under dipyridamole induced vasodilatation, and a possible impairment of the endothelium dependent vasodilation. This happened despite an increase in the left ventricular mass, where the relation between capillary bed distribution and hypertrophied myocardium (rarefaction phenomenon) is not completely respected., (Copyright 2002 The European Society of Cardiology. Published by Elsevier Science Ltd. All rights reserved.)