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Amiodarone-induced thyroid dysfunction occurs in about 15-20% of patients under amiodarone therapy. Amiodarone-induced hypothyroidism (AIH) can develop in patients with an apparently normal thyroid gland or in those with an underlying chronic autoimmune thyroiditis. On a clinical ground, AIH is not challenging and can be easily treated with L-thyroxine therapy. Amiodarone-induced thyrotoxicosis (AIT) can occur in patients with (AIT 1) or without (AIT 2) an underlying thyroid disease. AIT 1 is a true iodine-induced hyperthyroidism occurring in patients with an underlying thyroid autonomy while AIT 2 is a drug-induced destructive thyroiditis. According to the different pathogenetic mechanism, AIT 2 is treated with glucocorticoids while AIT 1 usually responds to thionamides. Thyroidectomy should be considered when AIT represents an imminent risk for cardiac conditions, when patients require a prompt resolution of thyrotoxicosis or when they do not respond to the medical therapy. An effective collaboration between cardiologists and endocrinologists is crucial in each part of the management of AIT patients, including the evaluation of cardiological conditions with regard to thyroid hormone excess and whether, or not, it is necessary to continue amiodarone therapy.

Congenital heart disease is the most frequent neonatal malformation, with an estimated prevalence between 0.8% and 1%. Echocardiography is an important tool for diagnosis and follow-up in cardiology, because it is easy to use, inexpensive, and noninvasive. The study of fetal heart by means of echocardiography allows early diagnosis and treatment of fetal heart anomalies and dysfunction, and such a technique is increasingly used. This exam is often required after morphological fetal echography, when a congenital heart disease is suspected or when there is an increased risk of congenital heart disease. Fetal echocardiography allows to evaluate the cardiac anatomy and function or cardiac rhythm. The purpose of this review is to summarize the main parameters and echocardiographic techniques for the assessment of heart rhythm and function: two-dimensional echocardiography, Doppler, tissue Doppler, and two-dimensional strain.

The possibilities of applying the laws of dynamics to the study of myocardial mechanics are remarkable and to some extent neglected to characterize ventricular performance by the imaging techniques. There are potentially useful applications derived from the analyses of Doppler flow velocity profiles of left ventricular outflow to be applied to the study of cardiovascular dynamics. They include ejection force, pressure-volume work and ventricular power. All these variables require measurements that are easy to obtain even during a standard examination, like stroke volume, ventricular outflow velocity, and the velocity-time integral.

The objective of this review was to explore the clinical relevance of Doppler echocardiographic techniques in the evaluation of right and left ventricular function. It is well known that echocardiographic and Doppler analysis are able to provide information about several hemodynamic parameters, such as cardiac output, diastolic filling pressure, vascular resistances and pulmonary arterial pressures. This integrated approach, completely reliable and non-invasive, could allow to obtain useful information not only from a diagnostic and prognostic point of view but also for a potential therapeutic management, either pharmacological or surgical. This review summarizes the current knowledge and the emerging applications of echocardiographic and Doppler techniques focusing on the close correlation between Doppler-derived data and those coming from invasive techniques. On the basis of these evidences, the importance, even in daily clinical practice, of a non-invasive catheterization laboratory is clear and able to supply key information about ventricular function and, at the same time, to avoid expensive and unpleasant invasive procedures for patients.

In cardiology, ventricular function has extensively been studied, whereas atrial function received less attention. For such a reason atrial function is less known. The aim of this review was to summarize the role of atrial function and to explain how echocardiography and new echocardiographic-derived techniques may be of help to better study atrial function.

Tissue Doppler is an ultrasound tool representing a useful completion of standard Doppler echocardiographic examination, The placement of pulsed tissue Doppler sample volume at the level of the different sites of the mitral annulus allows to obtain information on left ventricular global longitudinal (systolic and diastolic) function, whereas the sampling of tricuspid lateral annulus gives similar information on the right ventricular chamber. Myocardial early diastolic velocity (Em) is a marker of ventricular diastolic relaxation and the ratio obtainable between transmitral (or transtricuspid) E velocity and annular Em (E/Em ratio) is an accurate index of the level of filling pressure of the assessed ventricular chamber. Myocardial systolic velocity (Sm) as well as the frequency of acceleration of presystolic velocity, occurring during isovolumic contraction time, are indexes of systolic performance and their reduction is evident in several cardiac pathologies. Tissue Doppler-derived systolic and diastolic indexes have a recognized prognostic value in heart failure and after acute myocardial infarction. In these conditions they are able to predict both left ventricular remodeling and mortality.

Background: Based on various epidemiological observations, it has been hypothesized that there is a "diabetic cardiomyopathy" strictly related to diabetes per se and probably due to an increase in the collagen content at the myocardial level, to microangiopathy or to complex alteration of myocardial metabolic pattern. Ultrasonic tissue characterization has recently been applied with different methodological approaches in order to identify early structural alterations of the myocardium., Methods: We used two different methods of myocardial tissue characterization, i.e. integrated backscatter and videodensitometry, to analyze 26 type I diabetics without clinical symptoms, without hypertension or coronary artery disease, which were excluded on the basis of a negative exercise ECG, and in whom conventional echocardiographic parameters were normal. Seventeen healthy age- and sex-matched subjects were evaluated as the control group., Results: Of the common left ventricular functional indexes, only E/A ratio (expression of global diastolic function) was lower in diabetics compared with controls (p < 0.01). The integrated backscatter index (IBI%) at the septum and posterior wall was significantly higher in diabetics as compared to controls, expressing an increased collagen content on a myocardial level. The cyclic variation index (%) of the mean gray level (videodensitometry) was significantly lower in diabetics in comparison with controls, both for the septum (p < 0.0001) and posterior wall (p < 0.002). This probably expresses an altered intrinsic myocardial contractility, due to an increase in myocardial collagen content and/or impairment of micro-circulatory function., Conclusion: In agreement with previous studies, we found an altered behavior in myocardial tissue reflectivity in type I diabetics. The real significance of this finding in the "normal" heart is the subject of intense debate. One hypothesis is that these findings could be considered a very early index of a "diabetic cardiomyopathy".

Subclinical hypothyroidism in characterized by elevated TSH levels in the face of normal thyroid hormone concentrations. The purpose of this study was to evaluate whether these subjects show alterations of neuropsychological and behavioural features and of myocardial contractility as patients with overt hypothyroidism do. We evaluated in 14 subjects the hormonal profile (total and free T3 and T4, TSH), memory ability (Wechsler Memory Scale), behavioural reactivity (Crown & Crisp Experimental Index) and the pre-ejection period (isometric systole). We found an evident impairment of some cognitive functions correlated to memory and a behavioural alteration, perhaps secondary to the disease state, and moreover an early defect of myocardial contractility, represented by prolonged pre-ejection period. These results suggest that these patients should be treated with adequate doses of L-Thyroxine, like in overt hypothyroidism.

Echocardiographic indices of left ventricular volume and mass and electrocardiographic indices of left ventricular hypertrophy have evaluated in 25 patients with chronic aortic regurgitation and in 10 normal subjects. When the patients with aortic regurgitation were subdivided in three groups with increasing evidence of left ventricular hypertrophy, the echocardiographic measures of left ventricular dimension and mass were also found to be increased, with statistically significant differences between patients and controls and among the three groups of patients as well. A specially constructed cumulative electrocardiographic index of left ventricular hypertrophy (Sokolow and Lyon's index plus Lewis' index plus strain pattern) is correlated with the left ventricular end-diastolic diameter (r = 0.65; P less than 0.001), cross-sectional area (r = 0.65; p less than 0.001) and mass (r = 0.75; p less than 0.001) better than the isolated electrocardiographic indexes.

In 40 subjects, 15 mean age 70.7 +/- 5.6 with systolic-diastolic hypertension, 15 mean age 75.5 +/- 6.8 years with systolic hypertension and 10 mean age 73.6 +/- 5.1 normotensive control group we have analyzed with M-mode 2D echocardiography and echophonocardiography the following parameters: diastolic--EDD--and systolic diameter--SD--of left ventricle, diastolic thickness of septum--SSD--and posterior wall--SPPD--of left ventricle, left ventricular ejection fraction--EF--(Theicholtr. formula), radius posterior wall thickness--R/SPPD--, left ventricular mass--LVM--(Devereux' formula), and systolic time intervals (Q-A2, LVET, PEP and PEP/LVET). The differences between groups are: systolic-diastolic hypertensive patients have increased EDD, SPPD and LVM, reduction of EF and increased PEP/LVET ratio in comparison with B and C groups; systolic hypertension doesn't increase EDD; SSD and PEP/LVET increase, while the EF remains within normal limits. In the healthy aged subjects SSD, SPPD and LVM are normal.

The aim of the present study is to analyze variations of external cardiac work and of indices of myocardial oxygen consumption induced by upright tilting and hand-grip in volley-ball athletes (group A) in comparison with a group of normal subjects (group N). For this purpose we have used impedance cardiography, a simple, reproducible and non invasive technique, which is very reliable in evaluating both systolic time intervals and hemodynamic parameters such as stroke volume and cardiac output. No significant differences, of external cardiac work, double and triple product were observed between group A and N upon upright tilting. Hand-grip test, on the other hand, can differentiate the myocardial behaviour of trained people from that of the control group. The double product was significantly reduced in group A in comparison with group N (P less than 0.001 and the end of the test, P less than 0.05 after 30", P less than 0.001 after 1' and 3"). The triple product was significantly reduced in group A in comparison with group N at the end of the test (P less than 0.005). External cardiac work was always higher in group A in comparison with group N (P less than 0.02, at the stop P less than 0.05 after 30", P less than 0.01 after 1', P less than 0.0001 after 3'). Therefore in volleyball athletes the myocardium exhibits better mechanical performance than in normal subjects.

Our aim is to find a way to test the autonomic nervous dysfunction in diabetes mellitus by performing maximal deep-breathings during ECg recording. The subjects underwent ECG recording continously for 2 minutes: during the first minute they breathed regularly, in the second minute they accomplished 6 maximal deep breathings. The R-R intervals in the 1st, as well as the shortest R-R intervals during inspiration and the longest ones during expiration in the second minute were measured and expiration-inspiration ratio (E:I ratio) was calculated. A decreased variation of the R-R intervals from deep-breathings reveals the autonomic nervouis dysfunction . Our data suggest that in diabetes mellitus, R-R intervals show a decreased variation, able to demonstrate earlier autonomic neuropathy.