Diabetic cardiomyopathy (DCM), although a distinct clinical entity, is also a part of the diabetic atherosclerosis process. It may be independent of the coexistence of ischemic heart disease, hypertension, or other macrovascular complications. Its pathological substrate is characterized by the presence of myocardial damage, reactive hypertrophy, and intermediary fibrosis, structural and functional changes of the small coronary vessels, disturbance of the management of the metabolic cardiovascular load, and cardiac autonomic neuropathy. These alterations make the diabetic heart susceptible to ischemia and less able to recover from an ischemic attack. Arterial hypertension frequently coexists with and exacerbates cardiac functioning, leading to the premature appearance of heart failure. Classical and newer echocardiographic methods are available for early diagnosis. Currently, there is no specific treatment for DCM; targeting its pathophysiological substrate by effective risk management protects the myocardium from further damage and has a recognized primary role in its prevention. Its pathophysiological substrate is also the objective for the new therapies and alternative remedies.

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The aim of this study was to investigate to what extent the existence of objective signs of diabetic autonomic neuropathy affects the corrected QT interval (QTc) in diabetic subjects. A total of 105 diabetic subjects (type 1, n = 53; type 2, n = 52) as well as 40 matched (by age and sex) control subjects were studied. All subjects underwent the battery of five Ewing tests. Autonomic neuropathy was diagnosed if two of the five tests were abnormal. In addition, the result of each test was considered as normal (grade = 0), borderline (grade = 1) or abnormal (grade = 2), and on the basis of the sum of the scores we calculated a total score for autonomic neuropathy. The QTc interval was measured at rest, and a value > 440 ms was considered abnormal. The QTc interval was significantly more prolonged in diabetic persons with autonomic neuropathy than in those without neutopathy and in control subjects: 408.4 +/- 24.2 ms vs. 394.6 +/- 27.9 ms and 393.6 +/- 25.5 ms respectively (P = 0.001). Furthermore, multivariate analysis controlling for age, sex, systolic and diastolic blood pressure, body mass index (BMI), waist-hip ratio (WHR), smoking, type and duration of diabetes, type of treatment, HBA1c and total score of autonomic neuropathy eliminated the role of all these factors as potential confounders except for the total score of autonomic neuropathy, which was found to affect QTc interval independently and significantly (P = 0.012). In summary, the present study confirmed the well-known relation between autonomic neuropathy and QTc interval; in addition, it showed that QTc prolongation is associated with major degrees of autonomic neuropathy.

The spatial QRS-T angle obtained by vectorcardiography is a combined measurement of the electrical activity of the heart and predicts cardiovascular morbidity and mortality. Disturbances in repolarization and depolarization are common in diabetes. No data, however, exist on the effect of diabetes on QRS-T angle. In this study we examined differences in QRS-T angle between type 2 diabetic and non-diabetic subjects; in addition, the potential relationship between QRS-T angle and left ventricular performance as well as glycaemic control were also examined. A total of 74 subjects with type 2 diabetes and 74 non-diabetic individuals, matched for age and sex with the diabetic subjects were examined. All subjects were free of clinically apparent macrovascular complications. Spatial vectorcardiogaphic descriptors of ventricular depolarization and repolarization were reconstructed from the 12-electrocardiographic leads using a computer-based electrocardiogram. Left ventricular mass and performance were measured using M-mode and Doppler echocardiography. QRS-T angle values were higher (by almost 2-fold) in the diabetic in comparison with the non-diabetic subjects (P < 0.001). After multivariate adjustment, QRS-T angle was independently associated with age (P = 0.01), HbA(1c) (P = 0.003), and low-density lipoprotein cholesterol levels (P = 0.04) in the non-diabetic, and with HbA(1c) (P = 0.03) as well as Tei index (P = 0.003) in the diabetic subjects. The spatial QRS-T angle is high in subjects with type 2 diabetes and is associated with glycaemic control and left ventricular performance. The prognostic importance of the higher spQRS-T angle values in subjects with diabetes remains to be evaluated in prospective studies.

Masked hypertension is defined as low clinic and elevated out-of-clinic pressure (blood pressure, BP) assessed either by patients at home or by ambulatory monitoring. This study compared the cardiovascular status and psychometric characteristics of masked, white coat and sustained hypertensives. Three groups of consecutive subjects with masked (n ¼ 100, age 59 ± 11 years), white coat (n ¼ 100, 60 ± 10 years) and sustained hypertension (n ¼ 100, 60 ± 11 years) diagnosed by ambulatory BP monitoring were compared. Masked hypertensives had higher educational level, exercised more frequently, received fewer drugs and sensed more responsibilities at work than at home. Their left ventricular hypertrophy indexes fall inbetween those with white coat and sustained, the latter having the highest values. The estimated total cardiovascular risk was intermediate between white coat and sustained, whereas their cardiovascular morbidity and renal disease was higher than that of white coat and similar to sustained. Psychological profile analysis showed lower score for type-A personality and their mood behaviour in the hypomania-euthymia range compared with white coat and sustained hypertensives. The cardiovascular risk of masked hypertensives is higher than that of white coat and similar to sustained. Masked hypertensives have higher educational level, better physical training and different personality/mood pattern than white coat and sustained.