Delineating postinfarct ventricular tachycardia substrate with dynamic voltage mapping in areas of omnipolar vector disarray.

Background: Defining postinfarct ventricular arrhythmic substrate is challenging with voltage mapping alone, though it may be improved in combination with an activation map. Omnipolar technology on the EnSite X system displays activation as vectors that can be superimposed onto a voltage map. Objective: The study sought to optimize voltage map settings during ventricular tachycardia (VT) ablation, adjusting them dynamically using omnipolar vectors. Methods: Consecutive patients undergoing substrate mapping were retrospectively studied. We categorized omnipolar vectors as uniform when pointing in one direction, or in disarray when pointing in multiple directions. We superimposed vectors onto voltage maps colored purple in tissue >1.5 mV, and the voltage settings were adjusted so that uniform vectors appeared within purple voltages, a process termed dynamic voltage mapping (DVM). Vectors in disarray appeared within red-blue lower voltages. Results: A total of 17 substrate maps were studied in 14 patients (mean age 63 ± 13 years; mean left ventricular ejection fraction 35 ± 6%, median 4 [interquartile range 2-8.5] recent VT episodes). The DVM mean voltage threshold that differentiated tissue supporting uniform vectors from disarray was 0.27 mV, ranging between patients from 0.18 to 0.50 mV, with good interobserver agreement (median difference: 0.00 mV). We found that VT isthmus components, as well as sites of latest activation, isochronal crowding, and excellent pace maps colocated with tissue along the DVM border zone surrounding areas of disarray. Conclusion: DVM, guided by areas of omnipolar vector disarray, allows for individualized postinfarct ventricular substrate characterization. Tissue bordering areas of disarray may harbor greater arrhythmogenic potential.

Catheter-Related Right Atrial Endocarditis in a Dialysis Patient.

Hemodialysis catheters are frequently used for vascular access in end-stage chronic kidney disease patients lacking mature arteriovenous fistula. The incidence of infective endocarditis in hemodialysis patients is higher than in the general population and is associated with severe and potentially life-threatening complications. A high index of suspicion is imperative for early diagnosis and timely intervention to enhance the prognosis of this high-mortality condition. Imaging studies, like transthoracic and transesophageal echocardiography, are crucial for prompt diagnosis. We present a case of a 36-year-old woman undergoing hemodialysis, whose prolonged use of a permanent catheter led to the development of infective endocarditis complicated with septic pulmonary embolism. Our case report presents an example of right atrial endocarditis with a poor outcome due to delayed diagnosis.

Underuse of reperfusion therapy with systemic thrombolysis in high-risk acute pulmonary embolism in a Portuguese center.

INTRODUCTION: Reperfusion therapy is generally recommended in acute high-risk pulmonary embolism (HR-PE), but several population-based studies report that it is underused. Data on epidemiology, management and outcomes of HR-PE in Portugal are scarce. OBJECTIVE: To determine the reperfusion rate in HR-PE patients, the reasons for non-reperfusion, and how it influences outcomes. METHODS: In this retrospective cohort study of consecutive HR-PE patients admitted to a thromboembolic disease referral center between 2008 and 2018, independent predictors for non-reperfusion were assessed by multivariate logistic regression. PE-related mortality and long-term MACE (cardiovascular mortality, PE recurrence and chronic thromboembolic disease) were calculated according to the Kaplan-Meier method. Differences stratified by reperfusion were assessed using the log-rank test. RESULTS: Of 1955 acute PE patients, 3.8% presented with hemodynamic instability. The overall reperfusion rate was 50%: 35 patients underwent systemic thrombolysis, one received first-line percutaneous embolectomy and one rescue endovascular treatment. Independent predictors of non-reperfusion were: age, with >75 years representing 12 times the risk of non-treatment (OR 11.9, 95% CI 2.7-52.3, p=0.001); absolute contraindication for thrombolysis (31.1%), with recent major surgery and central nervous system disease as the most common reasons (OR 16.7, 95% CI 3.2-87.0, p<0.001); and being hospitalized (OR 7.7, 95% CI 1.4-42.9, p=0.020). At a mean follow-up of 2.5±3.3 years, the survival rate was 33.8%. Although not reaching statistical significance for hospital mortality, mortality in the reperfusion group was significantly lower at 30 days, 12 months and during follow-up (relative risk reduction of death of 64% at 12 months, p=0.013). Similar results were found for MACE. CONCLUSIONS: In this population, the recommended reperfusion therapy was performed in only 50% of patients, with advanced age and absolute contraindications to fibrinolysis being the main predictors of non-reperfusion. In this study, thrombolysis underuse was associated with a significant increase in short- and long-term mortality and events.

Percutaneous versus surgical revascularization of unprotected left main coronary artery: Data from the Portuguese Registry of Acute Coronary Syndromes (ProACS).

BACKGROUND: In acute coronary syndromes (ACS), the optimal revascularization strategy for unprotected left main coronary artery (ULMCA) culprit lesion has been under-investigated. Therefore, we compared clinical characteristics and short- and medium-term outcomes of percutaneous and surgical revascularization in ACS. METHODS AND RESULTS: Of 31886 patients enrolled in a multicenter, national, prospective registry study between October 2010 and December 2020, 246 (0.8%) had ULMCA as a culprit lesion and underwent percutaneous coronary intervention (PCI) alone (n=133, 54%) or coronary artery bypass grafting (CABG) alone (n=113, 46%). Patients undergoing PCI presented more frequently ongoing chest pain (68% versus 41%, p<0.001) and cardiogenic shock (25% versus 1%, p<0.001). Time from admission to revascularization was higher in surgical group with a median time to CABG of 4.5 days compared to 0 days to PCI (p<0.001). Angiographic success rate was 93.2% in patients who underwent PCI. Primary endpoint (all-cause death, non-fatal reinfarction and/or non-fatal stroke during hospitalization) occurred in 15.9% of patients and was more frequent in the PCI group (p<0.001). After adjustment, surgical revascularization was associated with better in-hospital prognosis (odds ratio (OR) 0.164; 95% confidence interval (CI), 0.04-0.64; p=0.009). Similar results were achieved after propensity score matching. No difference was found at one-year all-cause death. CONCLUSION: Percutaneous coronary intervention was the most common revascularization strategy in the ACS with ULMCA culprit lesion. PCI was preferred in unstable patients and presented a high angiographic success. CABG was often delayed and preferred in low-risk patients. At one-year follow-up, PCI and CABG conferred a similar prognosis. The two approaches appear complementary in this high risk cohort.