Abstract
Background
Patients with severe aortic stenosis (AS) are at risk of both bleeding and thrombotic events. The high shear and flow rates across the stenotic aortic valve (AV) degrade von ...Willebrand factor high molecular weight multimers increasing bleeding risk, but can also lead to platelet activation. The overall effect on thrombotic and endogenous fibrinolytic status remains unclear. We aimed to assess the relationship between AS severity and thrombotic and fibrinolytic profile.
Materials and methods
In a prospective, observational study, thrombotic and thrombolytic status was assessed in venous blood taken from patients with severe AS using the Global Thrombosis Test. This point-of-care technique measures the time for occlusive thrombus formation under high shear (OT), and the time for spontaneous lysis of the thrombus (LT). We related these parameters to indices of AS severity.
Results and conclusions
Our cohort comprised of 86 patients (age 79 ± 9 years, 58% male), of whom 25% were on single and 28% on dual antiplatelet medication, 47% on no antithrombotic therapy, and 1% on oral anticoagulation.
Lysis time was inversely related to AV peak (r = −0.242, P = 0.04) and mean (r = −0.286, P = 0.012) gradients. The severity of AS, by gradient or valve area, was not related to OT, although OT was inversely related to platelet count (r = −0.248, P = 0.029). Heterogeneity in antithrombotic medications may have masked a relationship between AS severity and OT.
We report that increasing severity of AS is related to more effective endogenous fibrinolysis, which may contribute to the increased propensity to bleeding.
Severe coronavirus disease 2019 is associated with an extensive pneumonitis and frequent coagulopathy. We sought the true prevalence of thrombotic complications in critically ill patients with severe ...coronavirus disease 2019 on the ICU, with or without extracorporeal membrane oxygenation.
We undertook a single-center, retrospective analysis of 72 critically ill patients with coronavirus disease 2019-associated acute respiratory distress syndrome admitted to ICU. CT angiography of the thorax, abdomen, and pelvis were performed at admission as per routine institution protocols, with further imaging as clinically indicated. The prevalence of thrombotic complications and the relationship with coagulation parameters, other biomarkers, and survival were evaluated.
Coronavirus disease 2019 ICUs at a specialist cardiorespiratory center.
Seventy-two consecutive patients with coronavirus disease 2019 admitted to ICU during the study period (March 19, 2020, to June 23, 2020).
None.
All but one patient received thromboprophylaxis or therapeutic anticoagulation. Among 72 patients (male:female = 74%; mean age: 52 ± 10; 35 on extracorporeal membrane oxygenation), there were 54 thrombotic complications in 42 patients (58%), comprising 34 pulmonary arterial (47%), 15 peripheral venous (21%), and five (7%) systemic arterial thromboses/end-organ embolic complications. In those with pulmonary arterial thromboses, 93% were identified incidentally on first screening CT with only 7% suspected clinically. Biomarkers of coagulation (e.g., d-dimer, fibrinogen level, and activated partial thromboplastin time) or inflammation (WBC count, C-reactive protein) did not discriminate between patients with or without thrombotic complications. Fifty-one patients (76%) survived to discharge; 17 (24%) patients died. Mortality was significantly greater in patients with detectable thrombus (33% vs 10%; p = 0.022).
There is a high prevalence of thrombotic complications, mainly pulmonary, among coronavirus disease 2019 patients admitted to ICU, despite anticoagulation. Detection of thrombus was usually incidental, not predicted by coagulation or inflammatory biomarkers, and associated with increased risk of death. Systematic CT imaging at admission should be considered in all coronavirus disease 2019 patients requiring ICU.
Midwall myocardial fibrosis on cardiovascular magnetic resonance (CMR) is a marker of early ventricular decompensation and adverse outcomes in aortic stenosis (AS). We aimed to develop and validate a ...novel clinical score using variables associated with midwall fibrosis.
One hundred forty-seven patients (peak aortic velocity (Vmax) 3.9 3.2,4.4 m/s) underwent CMR to determine midwall fibrosis (CMR cohort). Routine clinical variables that demonstrated significant association with midwall fibrosis were included in a multivariate logistic score. We validated the prognostic value of the score in two separate outcome cohorts of asymptomatic patients (internal: n = 127, follow-up 10.3 5.7,11.2 years; external: n = 289, follow-up 2.6 1.6,4.5 years). Primary outcome was a composite of AS-related events (cardiovascular death, heart failure, and new angina, dyspnoea, or syncope). The final score consisted of age, sex, Vmax, high-sensitivity troponin I concentration, and electrocardiographic strain pattern c-statistic 0.85 (95% confidence interval 0.78-0.91), P < 0.001; Hosmer-Lemeshow χ(2) = 7.33, P = 0.50. Patients in the outcome cohorts were classified according to the sensitivity and specificity of this score (both at 98%): low risk (probability score <7%), intermediate risk (7-57%), and high risk (>57%). In the internal outcome cohort, AS-related event rates were >10-fold higher in high-risk patients compared with those at low risk (23.9 vs. 2.1 events/100 patient-years, respectively; log rank P < 0.001). Similar findings were observed in the external outcome cohort (31.6 vs. 4.6 events/100 patient-years, respectively; log rank P < 0.001).
We propose a clinical score that predicts adverse outcomes in asymptomatic AS patients and potentially identifies high-risk patients who may benefit from early valve replacement.
Background
The ease of implantation of the rapid deployment (RD) and sutureless valves has contributed to the adoption of anterior right thoracotomy (ART) approach for aortic valve replacement (AVR).
...Aim of the study
This study evaluates the safety and haemodynamic performance of minimally invasive AVR through ART using the RD valves.
Methods
This is a retrospective, single‐center review of a total of 50 consecutive patients who received RD‐AVR through ART.
Results
The median age of patients was 75 years (interquartile range IQR: 69‐80), and median Euroscore II was 5.1 (IQR: 2.4‐7.5). ART RD‐AVR was successfully performed in all cases with no conversion to sternotomy, paravalvular leaks or need for valve explantation. The mean size of the implanted valve was 23.2 ± 2.3 mm. In‐hospital mortality was 2%. The mean and maximum pressure gradients across the aortic prosthesis were 10 mm Hg (IQR: 9‐12) and 19 mm Hg (IQR: 16‐23).
Conclusions
Rapid deployment aortic valve replacement can be safely performed through anterior right thoracotomy wit excellent haemodynamic performance and low postoperative complications rate.
Abstract
Aims
CT calcium scoring (CTCS) and CT cardiac angiography (CTCA) are widely used in patients with stable chest pain to exclude significant coronary artery disease (CAD). We aimed to resolve ...uncertainty about the prevalence of obstructive coronary artery disease and long-term outcomes in patients with a zero-calcium score (ZCS).
Methods and results
Consecutive patients with stable cardiac symptoms referred for CTCS or CTCS and CTCA from chest pain clinics to a tertiary cardiothoracic centre were prospectively enrolled. In those with a ZCS, the prevalence of obstructive CAD on CTCA was determined. A follow-up for all-cause mortality was obtained from the NHS tracer service. A total of 3914 patients underwent CTCS of whom 2730 (69.7%) also had a CTCA. Half of the patients were men (50.3%) with a mean age of 56.9 years. Among patients who had both procedures, a ZCS was present in 52.2%, with a negative predictive value of 99.5% for excluding ≥70% stenosis on CTCA. During a mean follow-up of 5.2 years, the annual event rate was 0.3% for those with ZCS compared with 1.2% for CS ≥1. The presence of non-calcified atheroma on CTCA in patients with ZCS did not affect the prognostic value (P = 0.98).
Conclusion
In patients with stable symptoms and a ZCS, obstructive CAD is rare, and prognosis over the long-term is excellent, regardless of whether non-calcified atheroma is identified. A ZCS could reliably be used as a ‘gatekeeper’ in this patient cohort, obviating the need for further more expensive tests.
This study assessed the utility of dual-energy pulmonary CT angiography (CTA) for noninvasive assessment of regional pulmonary perfusion in patients with chronic thromboembolic pulmonary hypertension ...(CTEPH). Regional perfusion abnormalities were correlated with hemodynamic parameters and structural abnormalities on pulmonary CTA.
Twenty patients with CTEPH (11 men and nine women; mean age, 61.5 years) underwent pulmonary CTA with a dual-energy technique. Right heart catheterization data were available in 15 cases. Scan parameters were as follows: tube A, 140 kV (75 mA); tube B, 80 kV (300 mA); gantry rotation, 500 milliseconds; pitch, 0.5; and collimation, 14 × 1.2 mm. An iodine map was generated via three-material-decomposition and was scored for extent of hypoperfusion. Correlation was made with mosaic attenuation pattern, extent of vascular obstruction, and right heart hemodynamics. Iodine attenuation values were analyzed within completely occluded, partially occluded, and disease-free lobes.
A strong correlation existed between dual-energy CT-derived perfusion and mosaic attenuation pattern when both lobar (r > 0.6; n = 20; p < 0.006) and whole-lung scores were assessed (r = 0.77; n = 20; p < 0.001). There was no statistically significant correlation between dual-energy CT perfusion and vascular obstructive index, mean pulmonary artery pressure, or pulmonary vascular resistance (p > 0.08). Of 42 completely occluded lobes, 27 (64%) had demonstrable residual perfusion (mismatching), suggesting that blood supply was maintained via systemic collaterals.
Dual-energy CT can offer a "one-stop" assessment of anatomy and perfusion in CTEPH. The additional information provided by dual-energy CT could have a future role in helping guide patient selection for thromboendarterectomy surgery.
Fractional flow reserve-computed tomography (FFR-CT) is endorsed by UK and U.S. chest pain guidelines, but its clinical effectiveness and cost benefit in real-world practice are unknown.
The purpose ...of this study was to audit the use of FFR-CT in clinical practice against England's National Institute for Health and Care Excellence guidance and assess its diagnostic accuracy and cost.
A multicenter audit was undertaken covering the 3 years when FFR-CT was centrally funded in England. For coronary computed tomographic angiograms (CCTAs) submitted for FFR-CT analysis, centers provided data on symptoms, CCTA and FFR-CT findings, and subsequent management. Audit standards included using FFR-CT only in patients with stable chest pain and equivocal stenosis (50%-69%). Diagnostic accuracy was evaluated against invasive FFR, when performed. Follow-up for nonfatal myocardial infarction and all-cause mortality was undertaken. The cost of an FFR-CT strategy was compared to alternative stress imaging pathways using cost analysis modeling.
A total of 2,298 CCTAs from 12 centers underwent FFR-CT analysis. Stable chest pain was the main symptom in 77%, and 40% had equivocal stenosis. Positive and negative predictive values of FFR-CT were 49% and 76%, respectively. A total of 46 events (2%) occurred over a mean follow-up period of 17 months; FFR-CT (cutoff: 0.80) was not predictive. The FFR-CT strategy costs £2,102 per patient compared with an average of £1,411 for stress imaging.
In clinical practice, the National Institute for Health and Care Excellence criteria for using FFR-CT were met in three-fourths of patients for symptoms and 40% for stenosis. FFR-CT had a low positive predictive value, making its use potentially more expensive than conventional stress imaging strategies.
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