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This paper proposes a novel DFT scheme that combines two test techniques—differential power supply current (Δ I DD) monitoring and differential output current (Δ I OUT) checking—in a single analog self-test. The DFT scheme is aimed at fully differential analog circuits. Fault detection is provided by means of differential measurement of the on-chip parameters, such as the I DD and I OUT currents. Due to the differential nature of the test principle used, no reference measurement is required prior to the test, thus the fault detection exhibits a significantly reduced dependency on process parameter variations, variation of temperature during the test as well as outside interference's. Based on measurement results, the realistic tolerance band for fault detection was determined and the fault coverage, resulting from previous simulation experiments, was adjusted. [ABSTRACT FROM AUTHOR]

In the last decades, advances in percutaneous coronary intervention (PCI) strategies have significantly reduced the risk of procedural complications and in-hospital mortality of patients with acute coronary syndromes (ACS), thus increasing the population of stable post-ACS patients. This novel epidemiological scenario emphasizes the importance of implementing secondary preventive and follow-up strategies. The follow-up of patients after ACS or elective PCI should be based on common pathways and on the close collaboration between hospital cardiologists and primary care physicians. However, the follow-up strategies of these patients are still poorly standardized. This SICI-GISE/SICOA consensus document was conceived as a proposal for the long-term management of post-ACS or post-PCI patients based on their individual residual risk of cardiovascular adverse events. We defined five patient risk classes and five follow-up strategies including medical visits and examinations according to a specific time schedule. We also provided a short guidance for the selection of the appropriate imaging technique for the assessment of left ventricular ejection fraction and of non-invasive anatomical or functional tests for the detection of obstructive coronary artery disease. Physical and pharmacological stress echocardiography was identified as the first-line imaging technique in most of cases, while cardiovascular magnetic resonance should be preferred when an accurate evaluation of left ventricular ejection fraction is needed. The standardization of the follow-up pathways of patients with a history of ACS or elective PCI, shared between hospital doctors and primary care physicians, could result in a more cost-effective use of resources and potentially improve patient's long-term outcome.

Context: Although coronary flow reserve (CFR) is reduced in patients with subclinical hypothyroidism (SHypo), the endothelial response of coronary vasomotion has never been explored in this clinical setting., Objective: To investigate the endothelial response of coronary flow in young and middle-aged patients with SHypo, without associated cardiovascular risk factors compared with healthy control subjects., Patients and Methods: The study population consisted of 20 women (mean age 38.4+12.1 years) with newly diagnosed, untreated and persistent SHypo due to Hashimoto's thyroiditis. A total of 15 volunteers served as controls. Age, gender, body surface area, glucose, insulin levels, heart rate, systolic, diastolic, and mean blood pressure were similar in patients and controls. Body mass index was significantly higher in SHypo patients. Total cholesterol and low-density lipoprotein cholesterol, despite not significant, tended to be higher, and high-density lipoprotein cholesterol to be lower in SHypo. Coronary blood flow velocities were recorded in patients at rest and after the cold pressor test (CPT), a stimulus that can be considered totally endothelium-dependent. CFR was calculated as the ratio of hyperemic-to-resting diastolic peak velocities., Results: Coronary diastolic peak velocities at rest did not differ between the two groups but were significantly lower after CPT in patients with SHypo, thereby resulting in a lower CFR. The difference remained significant after adjusting resting and CPT velocities for the respective mean blood pressures. TSH was inversely correlated with CFR in the pooled population., Conclusion: Patients with SHypo without associated cardiovascular risk factors have a coronary endothelial dysfunction that appears in response to a physiological stimulus (the CPT).

Background: Myotonic dystrophy is associated with arrhythmias and risk of sudden death but also with symptoms of heart failure. Our study aimed to identify early biventricular dysfunction in asymptomatic patients with myotonic dystrophy by tissue Doppler., Methods: Thirty-six patients with myotonic dystrophy (M/F=20/16, mean age=36.4 years), asymptomatic for heart failure, and 36 age- and sex-matched healthy controls underwent Doppler echocardiography and pulsed tissue Doppler of lateral mitral annulus and of tricuspid annulus., Results: The two groups had similar body mass index, blood pressure, heart rate, cardiac mass and endocardial shortening. Standard Doppler showed significantly lower transmitral early (E) diastolic peak velocity, longer transmitral deceleration and isovolumic relaxation times and higher tricuspid inflow atrial peak velocity in myotonic dystrophy than in controls. Tissue Doppler of mitral annulus showed lower myocardial systolic velocity (p<0.02), lower early diastolic velocity (E(m)) (p<0.05) and atrial velocity (A(m)) (p<0.005), but no difference of E(m)/A(m) ratio. At tricuspid annulus, E(m) and E(m)/A(m) ratio were lower (p<0.02 and p<0.005, respectively). The ratio between tricuspid inflow E velocity and E(m), index of the degree of right ventricular filling pressure, was higher (p<0.001) than in controls. Tissue Doppler derived left ventricular and right ventricular measurements were all associated with the disease condition, independent of age and heart rate., Conclusions: Tissue Doppler identifies subclinical biventricular involvement in myotonic dystrophy. Early left ventricular myocardial systolic and diastolic changes are evident. Right ventricular dysfunction, involving myocardial relaxation and right ventricular filling pressure, might be the arrhythmogenic substratum of these patients.

New ultrasound technology is mainly represented by tissue Doppler (TD), which allows the quantitative analysis of myocardial function and includes two modalies: pulsed-wave TD and color TD. Strain rate imaging (SRI) is an implementation of color TD. Pulsed-wave TD, performed and analyzed in real time, instantaneously measures myocardial velocities. Color TD, performed offline on digitally stored images, allows the quantification of mean myocardial velocities. The advantage of color TD compared with pulsed TD is the ability to simultaneously analyze multiple myocardial segments. The limit of both these methodologies consists of the myocardial velocity dependence by the base-apex myocardial gradient. SRI measures the rate and percentage of myocardial wall deformation. From digitally recorded color TD cine loops containing velocity data from the entire myocardium, SRI can be derived from regional Doppler velocity gradients. Strain rate is relatively load dependent, and, therefore, can be considered a strong index of myocardial contractility. Due to these favorable characteristics, SRI may potentially overcome the limitations of color TD, discriminating between active and merely passive wall motion. A novel technique is the implementation of 2D SRI, which is not angle dependent, and therefore potentially more feasible and reliable.