9 research outputs found
A physically based model for evaluating the Photon DetectionEfficiency and the Temporal Response of SPAD detectors
We present a physically-based model aimed at calculating the Photon Detection Efficiency (PDE) and the temporal response of a Single-Photon Avalanche Diode (SPAD) with a given structure. A comparison between simulation and experimental results is also reported in order to confirm the model accuracy
How do cardiologists select patients for dual antiplatelet therapy continuation beyond 1 year after a myocardial infarction? Insights from the EYESHOT Post-MI Study
Background: Current guidelines suggest to consider dual antiplatelet therapy (DAPT) continuation for longer than 12 months in selected patients with myocardial infarction (MI). Hypothesis: We sought to assess the criteria used by cardiologists in daily practice to select patients with a history of MI eligible for DAPT continuation beyond 1 year. Methods: We analyzed data from the EYESHOT Post-MI, a prospective, observational, nationwide study aimed to evaluate the management of patients presenting to cardiologists 1 to 3 years from the last MI event. Results: Out of the 1633 post-MI patients enrolled in the study between March and December 2017, 557 (34.1%) were on DAPT at the time of enrolment, and 450 (27.6%) were prescribed DAPT after cardiologist assessment. At multivariate analyses, a percutaneous coronary intervention (PCI) with multiple stents and the presence of peripheral artery disease (PAD) resulted as independent predictors of DAPT continuation, while atrial fibrillation was the only independent predictor of DAPT interruption for patients both at the second and the third year from MI at enrolment and the time of discharge/end of the visit. Conclusions: Risk scores recommended by current guidelines for guiding decisions on DAPT duration are underused and misused in clinical practice. A PCI with multiple stents and a history of PAD resulted as the clinical variables more frequently associated with DAPT continuation beyond 1 year from the index MI
Design-oriented simulation of the Photon Detection Efficiency and temporal response of Single Photon Avalanche Diodes
We present a physically-based model aimed at calculating the photon detection efficiency (PDE) and the temporal response of a single-photon avalanche diode (SPAD) with a given structure. A comparison between simulation and experimental results is also reported in order to confirm the model accuracy
Modeling photon detection efficiency and temporal response of single photon avalanche diodes
In this paper we present a physically-based model aimed at calculating the Photon Detection Efficiency (PDE) and the
temporal response of a Single-Photon Avalanche Diode (SPAD) with a given structure. In order to calculate these quantities, it is necessary to evaluate both the probability and the delay with which a photon impinging on the detector area triggers an avalanche. Three tasks are sequentially performed: as a first step, the electron-hole generation profile along the device is calculated according to the silicon absorption coefficient at the considered wavelength; successively, temporal evolution of the carriers distribution along the device is calculated by solving drift diffusion equations; finally, the avalanche triggering probability is calculated as a function of the photon absorption point.
Validation of the model has been carried out by comparing simulation and experimental results of a few generations of detectors previously realized in our laboratory. Photon detection efficiency has been measured and calculated for wavelengths ranging from 400nm to 1000nm and for excess bias voltages ranging from 2 to 8V. Similarly, temporal response has been investigated at two different wavelengths (520 and 820nm). A remarkable agreement between experimental and simulation results has been obtained in the entire characterization domain simply starting from the measured doping profile and without the need of any fitting parameter. Consequently, we think that this model will be a valuable tool for the development of new detectors with improved performances
How do cardiologists select patients for dual antiplatelet therapy continuation beyond 1 year after a myocardial infarction? Insights from the EYESHOT Post-MI Study
Background: Current guidelines suggest to consider dual antiplatelet therapy (DAPT) continuation for longer than 12 months in selected patients with myocardial infarction (MI). Hypothesis: We sought to assess the criteria used by cardiologists in daily practice to select patients with a history of MI eligible for DAPT continuation beyond 1 year. Methods: We analyzed data from the EYESHOT Post-MI, a prospective, observational, nationwide study aimed to evaluate the management of patients presenting to cardiologists 1 to 3 years from the last MI event. Results: Out of the 1633 post-MI patients enrolled in the study between March and December 2017, 557 (34.1%) were on DAPT at the time of enrolment, and 450 (27.6%) were prescribed DAPT after cardiologist assessment. At multivariate analyses, a percutaneous coronary intervention (PCI) with multiple stents and the presence of peripheral artery disease (PAD) resulted as independent predictors of DAPT continuation, while atrial fibrillation was the only independent predictor of DAPT interruption for patients both at the second and the third year from MI at enrolment and the time of discharge/end of the visit. Conclusions: Risk scores recommended by current guidelines for guiding decisions on DAPT duration are underused and misused in clinical practice. A PCI with multiple stents and a history of PAD resulted as the clinical variables more frequently associated with DAPT continuation beyond 1 year from the index MI
How do cardiologists select patients for dual antiplatelet therapy continuation beyond 1 year after a myocardial infarction? Insights from the EYESHOT Post-MI Study
Background: Current guidelines suggest to consider dual antiplatelet therapy (DAPT) continuation for longer than 12 months in selected patients with myocardial infarction (MI). Hypothesis: We sought to assess the criteria used by cardiologists in daily practice to select patients with a history of MI eligible for DAPT continuation beyond 1 year. Methods: We analyzed data from the EYESHOT Post-MI, a prospective, observational, nationwide study aimed to evaluate the management of patients presenting to cardiologists 1 to 3 years from the last MI event. Results: Out of the 1633 post-MI patients enrolled in the study between March and December 2017, 557 (34.1%) were on DAPT at the time of enrolment, and 450 (27.6%) were prescribed DAPT after cardiologist assessment. At multivariate analyses, a percutaneous coronary intervention (PCI) with multiple stents and the presence of peripheral artery disease (PAD) resulted as independent predictors of DAPT continuation, while atrial fibrillation was the only independent predictor of DAPT interruption for patients both at the second and the third year from MI at enrolment and the time of discharge/end of the visit. Conclusions: Risk scores recommended by current guidelines for guiding decisions on DAPT duration are underused and misused in clinical practice. A PCI with multiple stents and a history of PAD resulted as the clinical variables more frequently associated with DAPT continuation beyond 1 year from the index MI
Contemporary antithrombotic strategies in patients with acute coronary syndromes managed without revascularization: Insights fromthe EYESHOT study
Aims Patients with acute coronary syndromes (ACSs) whoare managed without coronary revascularization represent a mixed and understudied population that seems to receive suboptimal pharmacological treatment. Methods and results We assessed patterns of antithrombotic therapies employed during the hospitalization and in-hospital clinical events of medically managed patients withACS enrolled in the prospective, multicentre, nationwideEYESHOT(EmploYEd antithrombotic therapies in patients with acute coronary Syndromes HOspitalized in Italian cardiac care units) registry.Among the 2585 consecutive ACS patients enrolled in EYESHOT, 783 (30.3%) did not receive any revascularization during hospital admission. Of these, 478 (61.0%) underwent coronary angiography (CA), whereas 305 (39.0%) did not. The median GRACE and CRUSADE risk scores were significantly higher among patients who did not undergo CA compared with those who did (180 vs. 145, P, 0.0001 and 50 vs. 33, P, 0.0001, respectively). Antithrombotic therapies employed during hospitalization significantly differ between patients who received CA and those who did not with unfractioned heparin and novel P2Y12 inhibitors more frequently used in the first group, and low-molecular-weight heparins and clopidogrel in the latter group. During the index hospitalization, patients who did not receive CA presented a higher incidence of ischaemic cerebrovascular events and of mortality compared with those who underwent CA (1.6 vs. 0.2%, P = 0.04 and 7.9 vs. 2.7%, P = 0.0009, respectively). Conclusion Almost one-third of ACS patients are managed without revascularization during the index hospitalization. In this population, a lower use of recommended antiplatelet therapy and worse clinical outcome were observed in those who did not undergo CA when compared with those who did
Antithrombotic strategies in the catheterization laboratory for patients with acute coronary syndromes undergoing percutaneous coronary interventions: Insights from the EmploYEd antithrombotic therapies in patients with acute coronary Syndromes HOspitalized in Italian cardiac care units Registry
Aims: In the last decades, several new therapies have emerged for the treatment of acute coronary syndromes (ACS). We sought to describe real-world patterns of use of antithrombotic treatments in the catheterization laboratory for ACS patients undergoing percutaneous coronary interventions (PCI). Methods: EmploYEd antithrombotic therapies in patients with acute coronary Syndromes HOspitalized in Italian cardiac care units was a nationwide, prospective registry aimed to evaluate antithrombotic strategies employed in ACS patients in Italy. Results: Over a 3-week period, a total of 2585 consecutive ACS patients have been enrolled in 203 cardiac care units across Italy. Among these patients, 1755 underwent PCI (923 with ST-elevation myocardial infarction and 832 with non-ST-elevation ACS). In the catheterization laboratory, unfractioned heparin was the most used antithrombotic drug in both ST-elevation myocardial infarction (64.7%) and non-ST-elevation ACS (77.5%) undergoing PCI and, as aspirin, bivalirudin and glycoprotein IIb/IIIa inhibitors (GPIs) more frequently employed before or during PCI compared with the postprocedural period. Any crossover of heparin therapy occurred in 36.0% of cases, whereas switching from one P2Y12 inhibitor to another occurred in 3.7% of patients. Multivariable analysis yielded several independent predictors of GPIs and of bivalirudin use in the catheterization laboratory, mainly related to clinical presentation, PCI complexity and presence of complications during the procedure. Conclusion: In our contemporary, nationwide, all-comers cohort of ACS patients undergoing PCI, antithrombotic therapies were commonly initiated before the catheterization laboratory. In the periprocedural period, the most frequently employed drugs were unfractioned heparin, leading to a high rate of crossover, followed by GPIs and bivalirudin, mainly used during complex PCI