On the detection of myocardial scar based on ECG/VCG analysis

In this paper, we address the problem of detecting the presence of myocardial scar from standard ECG/VCG recordings, giving effort to develop a screening system for the early detection of scar in the point-of-care. Based on the pathophysiological implications of scarred myocardium, which results in disordered electrical conduction, we have implemented four distinct ECG signal processing methodologies in order to obtain a set of features that can capture the presence of myocardial scar. Two of these methodologies: a.) the use of a template ECG heartbeat, from records with scar absence coupled with Wavelet coherence analysis and b.) the utilization of the VCG are novel approaches for detecting scar presence. Following, the pool of extracted features is utilized to formulate an SVM classification model through supervised learning. Feature selection is also employed to remove redundant features and maximize the classifier's performance. Classification experiments using 260 records from three different databases reveal that the proposed system achieves 89.22% accuracy when applying 10- fold cross validation, and 82.07% success rate when testing it on databases with different inherent characteristics with similar levels of sensitivity (76%) and specificity (87.5%)

Is It Really Safe to Discontinue Antiplatelet Therapy 12 Months After Percutaneous Coronary Intervention in Patients with Atrial Fibrillation?

The prevalence of AF in patients with coronary artery disease is high. The guidelines from many professional groups, including the European Society of Cardiology, American College of Cardiology/American Heart Association and Heart Rhythm Society, recommend a maximum duration of 12 months of combination single antiplatelet and anticoagulation therapy in patients who undergo percutaneous coronary intervention and who have concurrent AF, followed by anticoagulation alone beyond 1 year. However, the evidence that anticoagulation alone without antiplatelet therapy adequately reduces the well-documented attritional risk of stent thrombosis after coronary stent implantation is relatively sparse, particularly given that very late stent thrombosis (>1 year from stent implantation) is the commonest type. By contrast, the elevated risk of bleeding from combined anticoagulation and antiplatelet therapy is clinically important. The aim of this review is to assess the evidence for long-term anticoagulation alone without antiplatelet therapy 1 year post-percutaneous coronary intervention in patients with AF

Point-of-care platelet function assays demonstrate reduced responsiveness to clopidogrel, but not aspirin, in patients with Drug-Eluting Stent Thrombosis whilst on dual antiplatelet therapy

BackgroundTo test the hypothesis that point-of-care assays of platelet reactivity would demonstrate reduced response to antiplatelet therapy in patients who experienced Drug Eluting Stent (DES) ST whilst on dual antiplatelet therapy compared to matched DES controls. Whilst the aetiology of stent thrombosis (ST) is multifactorial there is increasing evidence from laboratory-based assays that hyporesponsiveness to antiplatelet therapy is a factor in some cases.MethodsFrom 3004 PCI patients, seven survivors of DES ST whilst on dual antiplatelet therapy were identified and each matched with two patients without ST. Analysis was performed using (a) short Thrombelastogram PlateletMapping™ (TEG) and (b) VerifyNow Aspirin and P2Y12 assays. TEG analysis was performed using the Area Under the Curve at 15 minutes (AUC15) as previously described.ResultsThere were no differences in responses to aspirin. There was significantly greater platelet reactivity on clopidogrel in the ST group using the Accumetrics P2Y12 assay (183 ± 51 vs. 108 ± 31, p = 0.02) and a trend towards greater reactivity using TEG AUC15 (910 ± 328 vs. 618 ± 129, p = 0.07). 57% of the ST group by TEG and 43% of the ST cases by Accumetrics PRU had results > two standard deviations above the expected mean in the control group.ConclusionThis study demonstrates reduced platelet response to clopidogrel in some patients with DES ST compared to matched controls. The availability of point-of-care assays that can detect these responses raises the possibility of prospectively identifying DES patients at risk of ST and manipulating their subsequent risk

Sensitivity and specificity of the subcutaneous implantable cardioverter defibrillator pre-implant screening tool

BackgroundThe sensitivity and specificity of the subcutaneous implantable cardioverter defibrillator (S-ICD) pre-implant screening tool required clinical evaluation.MethodsBipolar vectors were derived from electrodes positioned at locations similar to those employed for S-ICD sensing and pre-implant screening electrodes, and recordings collected through 80-electrode PRIME®-ECGs, in six different postures, from 40 subjects (10 healthy controls, and 30 patients with complex congenital heart disease (CCHD); 10 with Tetralogy of Fallot (TOF), 10 with single ventricle physiology (SVP), and 10 with transposition of great arteries (TGA)). The resulting vectors were analysed using the S-ICD pre-implant screening tool (Boston Scientific) and processed through the sensing algorithm of S-ICD (Boston Scientific). The data were then evaluated using 2 × 2 contingency tables. Fisher exact and McNemar tests were used for a comparison of the different categories of CCHD, and p < 0.05 vs. controls considered to be statistically significant.Results57% of patients were male, mean age of 36.3 years. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the S-ICD screening tool were 95%, 79%, 59% and 98%, respectively, for controls, and 84%, 79%, 76% and 86%, respectively, in patients with CCHD (p = 0.0001).ConclusionThe S-ICD screening tool was comparatively more sensitive in normal controls but less specific in both CCHD patients and controls; a possible explanation for the reported high incidence of inappropriate S-ICD shocks. Thus, we propose a pre-implant screening device using the S-ICD sensing algorithm to minimise false exclusion and selection, and hence minimise potentially inappropriate shocks

Fractional flow reserve versus angiography in guiding management to optimize outcomes in non–ST-elevation myocardial infarction (FAMOUS-NSTEMI): rationale and design of a randomized controlled clinical trial

<p>Background: In patients with acute non–ST-elevation myocardial infarction (NSTEMI), coronary arteriography is usually recommended; but visual interpretation of the angiogram is subjective. We hypothesized that functional assessment of coronary stenosis severity with a pressure-sensitive guide wire (fractional flow reserve [FFR]) would have additive diagnostic, clinical, and health economic utility as compared with angiography-guided standard care.</p> <p>Methods and design: A prospective multicenter parallel-group 1:1 randomized controlled superiority trial in 350 NSTEMI patients with ≥1 coronary stenosis ≥30% severity (threshold for FFR measurement) will be conducted. Patients will be randomized immediately after coronary angiography to the FFR-guided group or angiography-guided group. All patients will then undergo FFR measurement in all vessels with a coronary stenosis ≥30% severity including culprit and nonculprit lesions. Fractional flow reserve will be disclosed to guide treatment in the FFR-guided group but not disclosed in the “angiography-guided” group. In the FFR-guided group, an FFR ≤0.80 will be an indication for revascularization by percutaneous coronary intervention or coronary artery bypass surgery, as appropriate. The primary outcome is the between-group difference in the proportion of patients allocated to medical management only compared with revascularization. Secondary outcomes include the occurrence of cardiac death or hospitalization for myocardial infarction or heart failure, quality of life, and health care costs. The minimum and average follow-up periods for the primary analysis are 6 and 18 months, respectively.</p> <p>Conclusions: Our developmental clinical trial will address the feasibility of FFR measurement in NSTEMI and the influence of FFR disclosure on treatment decisions and health and economic outcomes.</p&gt

Impact of incomplete percutaneous revascularization in patients With multivessel coronary artery disease: a systematic review and meta-analysis

Background: Up to half of patients undergoing percutaneous coronary intervention have multivessel coronary artery disease (MVD) with conflicting data regarding optimal revascularization strategy in such patients. This paper assesses the evidence for complete revascularization (CR) versus incomplete revascularization in patients undergoing percutaneous coronary intervention, and its prognostic impact using meta‐analysis. Methods and Results: A search of PubMed, EMBASE, MEDLINE, Current Contents Connect, Google Scholar, Cochrane library, Science Direct, and Web of Science was conducted to identify the association of CR in patients with multivessel coronary artery disease undergoing percutaneous coronary intervention with major adverse cardiac events and mortality. Random‐effects meta‐analysis was used to estimate the odds of adverse outcomes. Meta‐regression analysis was conducted to assess the relationship with continuous variables and outcomes. Thirty‐eight publications that included 156 240 patients were identified. Odds of death (OR 0.69, 95% CI 0.61‐0.78), repeat revascularization (OR 0.60, 95% CI 0.45‐0.80), myocardial infarction (OR 0.64, 95% CI 0.50‐0.81), and major adverse cardiac events (OR 0.63, 95% CI 0.50‐0.79) were significantly lower in the patients who underwent CR. These outcomes were unchanged on subgroup analysis regardless of the definition of CR. Similar findings were recorded when CR was studied in the chronic total occlusion (CTO) subgroup (OR 0.65, 95% CI 0.53‐0.80). A meta‐regression analysis revealed a negative relationship between the OR for mortality and the percentage of CR. Conclusion: CR is associated with reduced risk of mortality and major adverse cardiac events, irrespective of whether an anatomical or a score‐based definition of incomplete revascularization is used, and this magnitude of risk relates to degree of CR. These results have important implications for the interventional management of patients with multivessel coronary artery disease

Impact of Social Vulnerability on Diabetes-Related Cardiovascular Mortality in the United States

Background: Social vulnerability impacts the natural history of diabetes as well as cardiovascular disease (CVD). However, there are little data regarding the social vulnerability association with diabetes-related CVD mortality. Methods and Results County-level mortality data (where CVD was the underlying cause of death with diabetes among the multiple causes) extracted from the Centers for Disease Control multiple cause of death (2015-2019) and the 2018 Social Vulnerability Index databases were aggregated into quartiles based on their Social Vulnerability Index ranking from the least (first quartile) to the most vulnerable (fourth quartile). Stratified by demographic groups, the data were analyzed for overall CVD, as well as for ischemic heart disease, hypertensive disease, heart failure, and cerebrovascular disease. In the 5-year study period, 387 139 crude diabetes-related cardiovascular mortality records were identified. The age-adjusted mortality rate for CVD was higher in the fourth quartile compared with the first quartile (relative risk [RR], 1.66 [95% CI, 1.64-1.67]) with an estimated 39 328 excess deaths. Among the youngest age group (<55 years), those with the highest social vulnerability had 2 to 4 times the rate of cardiovascular mortality compared with the first quartile: ischemic heart disease (RR, 2.07 [95% CI, 1.97-2.17]; heart failure (RR, 3.03 [95% CI, 2.62-3.52]); hypertensive disease (RR, 3.79 [95% CI, 3.45-4.17]; and cerebrovascular disease (RR, 4.39 [95% CI, 3.75-5.13]). Conclusions Counties with greater social vulnerability had higher diabetes-related CVD mortality, especially among younger adults. Targeted health policies that are designed to reduce these disparities are warranted

Safety of guidewire-based measurement of fractional flow reserve and the index of microvascular resistance using intravenous adenosine in patients with acute or recent myocardial infarction

Aims: Coronary guidewire-based diagnostic assessments with hyperemia may cause iatrogenic complications. We assessed the safety of guidewire-based measurement of coronary physiology, using intravenous adenosine, in patients with an acute coronary syndrome. Methods: We prospectively enrolled invasively managed STEMI and NSTEMI patients in two simultaneously conducted studies in 6 centers (NCT01764334; NCT02072850). All of the participants underwent a diagnostic coronary guidewire study using intravenous adenosine (140 μg/kg/min) infusion for 1–2 min. The patients were prospectively assessed for the occurrence of serious adverse events (SAEs) and symptoms and invasively measured hemodynamics were also recorded. Results: 648 patients (n = 298 STEMI patients in 1 hospital; mean time to reperfusion 253 min; n = 350 NSTEMI in 6 hospitals; median time to angiography from index chest pain episode 3 (2, 5) days) were included between March 2011 and May 2013. Two NSTEMI patients (0.03% overall) experienced a coronary dissection related to the guidewire. No guidewire dissections occurred in the STEMI patients. Chest symptoms were reported in the majority (86%) of patient's symptoms during the adenosine infusion. No serious adverse events occurred during infusion of adenosine and all of the symptoms resolved after the infusion ceased. Conclusions: In this multicenter analysis, guidewire-based measurement of FFR and IMR using intravenous adenosine was safe in patients following STEMI or NSTEMI. Self-limiting symptoms were common but not associated with serious adverse events. Finally, coronary dissection in STEMI and NSTEMI patients was noted to be a rare phenomenon

Burden of 30-Day Readmissions After Percutaneous Coronary Intervention in 833,344 Patients in the United States:Predictors, Causes, and Cost: Insights From the Nationwide Readmission Database

Objectives This study aimed to examine the 30-day unplanned readmissions rate, predictors of readmission, causes of readmissions, and clinical impact of readmissions after percutaneous coronary intervention (PCI). Background Unplanned rehospitalizations following PCI carry significant burden to both patients and the local health care economy and are increasingly considered as an indicator of quality of care. Methods Patients undergoing PCI between 2013 and 2014 in the U.S. Nationwide Readmission Database were included. Incidence, predictors, causes, and cost of 30-day unplanned readmissions were determined. Results A total of 833,344 patients with PCI were included, of whom 77,982 (9.3%) had an unplanned readmission within 30 days. Length of stay for the index PCI was greater (4.7 vs. 3.9 days) and mean total hospital cost ($23,211 vs.$37,524) was higher for patients who were readmitted compared with those not readmitted. The factors strongly independently associated with readmissions were index hospitalization discharge against medical advice (odds ratio [OR]: 1.91; 95% confidence interval [CI]: 1.65 to 2.22), transfer to short-term hospital for inpatient care (OR: 1.62; 95% CI: 1.38 to 1.90), discharge to care home (OR: 1.57; 95% CI: 1.51 to 1.64), and chronic kidney disease (OR: 1.50; 95% CI: 1.44 to 1.55). Charlson Comorbidity Index score (OR: 1.28; 95% CI: 1.27 to 1.29) and number of comorbidities (OR: 1.18; 95% CI: 1.17 to 1.18) were independently associated with unplanned readmission. The majority of readmissions were due to noncardiac causes (56.1%). Conclusions Thirty-day readmissions after PCI are relatively common and relate to baseline comorbidities and place of discharge. More than one-half of the readmissions were due to noncardiac causes