The use of non-invasive imaging to identify ruptured or high-risk coronary atherosclerotic plaques would represent a major clinical advance for prevention and treatment of coronary artery disease. We ...used combined PET and CT to identify ruptured and high-risk atherosclerotic plaques using the radioactive tracers 18F-sodium fluoride (18F-NaF) and 18F-fluorodeoxyglucose (18F-FDG).
In this prospective clinical trial, patients with myocardial infarction (n=40) and stable angina (n=40) underwent 18F-NaF and 18F-FDG PET-CT, and invasive coronary angiography. 18F-NaF uptake was compared with histology in carotid endarterectomy specimens from patients with symptomatic carotid disease, and with intravascular ultrasound in patients with stable angina. The primary endpoint was the comparison of 18F-fluoride tissue-to-background ratios of culprit and non-culprit coronary plaques of patients with acute myocardial infarction.
In 37 (93%) patients with myocardial infarction, the highest coronary 18F-NaF uptake was seen in the culprit plaque (median maximum tissue-to-background ratio: culprit 1·66 IQR 1·40–2·25 vs highest non-culprit 1·24 1·06–1·38, p<0·0001). By contrast, coronary 18F-FDG uptake was commonly obscured by myocardial uptake and where discernible, there were no differences between culprit and non-culprit plaques (1·71 1·40–2·13 vs 1·58 1·28–2·01, p=0·34). Marked 18F-NaF uptake occurred at the site of all carotid plaque ruptures and was associated with histological evidence of active calcification, macrophage infiltration, apoptosis, and necrosis. 18 (45%) patients with stable angina had plaques with focal 18F-NaF uptake (maximum tissue-to-background ratio 1·90 IQR 1·61–2·17) that were associated with more high-risk features on intravascular ultrasound than those without uptake: positive remodelling (remodelling index 1·12 1·09–1·19 vs 1·01 0·94–1·06; p=0·0004), microcalcification (73% vs 21%, p=0·002), and necrotic core (25% 21–29 vs 18% 14–22, p=0·001).
18F-NaF PET-CT is the first non-invasive imaging method to identify and localise ruptured and high-risk coronary plaque. Future studies are needed to establish whether this method can improve the management and treatment of patients with coronary artery disease.
Chief Scientist Office Scotland and British Heart Foundation.
Vascular Effects of Apelin In Vivo in Man Japp, Alan G., MRCP; Cruden, Nicholas L., PhD; Amer, David A.B ...
Journal of the American College of Cardiology,
09/2008, Letnik:
52, Številka:
11
Journal Article
Recenzirano
Odprti dostop
Vascular Effects of Apelin In Vivo in Man Alan G. Japp, Nicholas L. Cruden, David A. B. Amer, Vivienne K. Y. Li, Ewan B. Goudie, Neil R. Johnston, Sushma Sharma, Ilene Neilson, David J. Webb, Ian L. ...Megson, Andrew D. Flapan, David E. Newby Using the Aellig hand vein technique and forearm venous occlusion plethysmography, we aimed to establish the direct vascular effects of apelin in vivo in man. Apelin-36 and (Pyr1 )apelin-13 had no effect on dorsal hand vein diameter (p = 0.2) but both isoforms caused vasodilation in forearm resistance vessels (p < 0.0001). Apelin-mediated vasodilation was attenuated by the nitric oxide clamp (a balanced coinfusion of the nitric oxide synthase inhibitor, L- NG -monomethylarginine, and nitric oxide donor, sodium nitroprusside; p = 0.004) but unaffected by aspirin (p = 0.7). Although having no apparent effect on venous tone, apelin causes nitric oxide-dependent arterial vasodilation in vivo in man.
Aims We sought to investigate the impact of body mass index (BMI) on long-term all-cause mortality in patients following first-time elective percutaneous coronary intervention (PCI). Methods and ...results We used the Scottish Coronary Revascularisation Register to undertake a cohort study of all patients undergoing elective PCI in Scotland between April 1997 and March 2006 inclusive. We excluded patients who had previously undergone revascularization. There were 219 deaths within 5 years of 4880 procedures. Compared with normal weight individuals, those with a BMI ≥27.5 and <30 were at reduced risk of dying (HR 0.59, 95% CI 0.39–0.90, 95%, P = 0.014). There was no attenuation of the association after adjustment for potential confounders, including age, hypertension, diabetes, and left ventricular function (adjusted HR 0.59, 95% CI 0.39–0.90, P = 0.015), and there were no statistically significant interactions. The results were unaltered by restricting the analysis to events beyond 30 days of follow-up. Conclusion Among patients undergoing percutaneous intervention for coronary artery disease, increased BMI was associated with improved 5 year survival. Among those with established coronary disease, the adverse effects of excess adipose tissue may be offset by beneficial vasoactive properties.
First-phase ejection fraction (EF1) is a novel measure of early left ventricular systolic dysfunction. We investigated determinants of EF1 and its prognostic value in aortic stenosis.
EF1 was ...measured retrospectively in participants of an echocardiography/cardiovascular magnetic resonance cohort study which recruited patients with aortic stenosis (peak aortic velocity of ≥2 m/s) between 2012 and 2014. Linear regression models were constructed to examine variables associated with EF1. Cox proportional hazards were used to determine the prognostic power of EF1 for aortic valve replacement (AVR, performed as part of clinical care in accordance with international guidelines) or death.
Total follow-up of the 149 participants (69.8% male, 70 (65-76) years, mean gradient 33 (21-42) mm Hg) was 238 029 person-days. Sixty-seven participants (45%) had a low baseline EF1 (<25%) despite normal ejection fraction (67% (62%-71%)). Patients with low EF1 had more severe aortic stenosis (mean gradient 39 (34-45) mm Hg vs 24 (16-35) mm Hg, p<0.001) and more myocardial fibrosis (indexed extracellular volume (iECV) (24.2 (19.6-28.7) mL/m
vs 20.6 (16.8-24.3) mL/m
, p=0.002; late gadolinium enhancement (LGE) prevalence 52% vs 20%, p<0.001). Zva, iECV and infarct LGE were independent predictors of EF1. EF1 improved post-AVR (n=57 with post-AVR EF1 available, baseline 16 (12-24) vs follow-up 27% (22%-31%); p<0.001). Low baseline EF1 was an independent predictor of AVR/death (HR 5.6, 95% CI 3.4 to 9.4), driven by AVR.
EF1 quantifies early, potentially reversible systolic dysfunction in aortic stenosis, is associated with global afterload and myocardial fibrosis, and is an independent predictor of AVR.
Rates of myocardial infarction in firefighters are increased during fire suppression duties, and are likely to reflect a combination of factors including extreme physical exertion and heat exposure. ...We assessed the effects of simulated fire suppression on measures of cardiovascular health in healthy firefighters.
In an open-label randomized crossover study, 19 healthy firefighters (age, 41±7 years; 16 males) performed a standardized training exercise in a fire simulation facility or light duties for 20 minutes. After each exposure, ex vivo thrombus formation, fibrinolysis, platelet activation, and forearm blood flow in response to intra-arterial infusions of endothelial-dependent and -independent vasodilators were measured.
After fire simulation training, core temperature increased (1.0±0.1°C) and weight reduced (0.46±0.14 kg,
<0.001 for both). In comparison with control, exposure to fire simulation increased thrombus formation under low-shear (73±14%) and high-shear (66±14%) conditions (
<0.001 for both) and increased platelet-monocyte binding (7±10%,
=0.03). There was a dose-dependent increase in forearm blood flow with all vasodilators (
<0.001), which was attenuated by fire simulation in response to acetylcholine (
=0.01) and sodium nitroprusside (
=0.004). This was associated with a rise in fibrinolytic capacity, asymptomatic myocardial ischemia, and an increase in plasma cardiac troponin I concentrations (1.4 0.8-2.5 versus 3.0 1.7-6.4 ng/L,
=0.010).
Exposure to extreme heat and physical exertion during fire suppression activates platelets, increases thrombus formation, impairs vascular function, and promotes myocardial ischemia and injury in healthy firefighters. Our findings provide pathogenic mechanisms to explain the association between fire suppression activity and acute myocardial infarction in firefighters.
URL: http://www.clinicaltrials.gov. Unique identifier: NCT01812317.
Noncardiac surgery performed after coronary stent implantation is associated with an increased risk of stent thrombosis, myocardial infarction, and death. The influence of stent type and period of ...risk still have to be defined.
We linked the Scottish Coronary Revascularisation Register with hospital admission data to undertake a Scotland-wide retrospective cohort study examining cardiac outcomes in all patients who received drug-eluting or bare-metal stents between April 2003 and March 2007 and subsequently underwent noncardiac surgery. Of 1953 patients, 570 (29%) were treated with at least 1 drug-eluting stent and 1383 (71%) with bare-metal stents only. There were no differences between drug-eluting and bare-metal stents in the primary end point of in-hospital mortality or ischemic cardiac events (14.6% versus 13.3%; P=0.3) or the secondary end points of in-hospital mortality (0.7% versus 0.6%; P=0.8) and acute myocardial infarction (1.2% versus 0.7%; P=0.3). Perioperative death and ischemic cardiac events occurred more frequently when surgery was performed within 42 days of stent implantation (42.4% versus 12.8% beyond 42 days; P<0.001), especially in patients revascularized after an acute coronary syndrome (65% versus 32%; P=0.037). There were no temporal differences in outcomes between the drug-eluting and bare-metal stent groups.
Patients undergoing noncardiac surgery after recent coronary stent implantation are at increased risk of perioperative myocardial ischemia, myocardial infarction, and death, particularly after an acute coronary syndrome. For at least 2 years after percutaneous coronary intervention, cardiac outcomes after noncardiac surgery are similar for both drug-eluting and bare-metal stents.
Patients with chronic heart failure (CHF) have a continuing high mortality. Autonomic dysfunction may play an important role in the pathophysiology of cardiac death in CHF. UK-HEART examined the ...value of heart rate variability (HRV) measures as independent predictors of death in CHF.
In a prospective study powered for mortality, we recruited 433 outpatients 62+/-9.6 years old with CHF (NYHA functional class I to III; mean ejection fraction, 0.41+/-0.17). Time-domain HRV indices and conventional prognostic indicators were related to death by multivariate analysis. During 482+/-161 days of follow-up, cardiothoracic ratio, SDNN, left ventricular end-systolic diameter, and serum sodium were significant predictors of all-cause mortality. The risk ratio for a 41.2-ms decrease in SDNN was 1.62 (95% CI, 1.16 to 2.44). The annual mortality rate for the study population in SDNN subgroups was 5.5% for >100 ms, 12.7% for 50 to 100 ms, and 51.4% for <50 ms. SDNN, creatinine, and serum sodium were related to progressive heart failure death. Cardiothoracic ratio, left ventricular end-diastolic diameter, the presence of nonsustained ventricular tachycardia, and serum potassium were related to sudden cardiac death. A reduction in SDNN was the most powerful predictor of the risk of death due to progressive heart failure.
CHF is associated with autonomic dysfunction, which can be quantified by measuring HRV. A reduction in SDNN identifies patients at high risk of death and is a better predictor of death due to progressive heart failure than other conventional clinical measurements. High-risk subgroups identified by this measurement are candidates for additional therapy after prescription of an ACE inhibitor.
This article briefly discusses the cardiac status of liver transplant recipients and their preoperative cardiac evaluation. It describes in detail perioperative and early and late postoperative ...complications as well as the cardiac problems associated with immunosuppression. The preoperative cardiovascular status of patients is important in determining how they cope with the stresses imposed by liver transplantation. Minor early cardiac events are common and may influence longer term cardiac morbidity. Immunosuppressive therapy may have short term effects but is likely to adversely affect long term cardiac risk. (Liver Transpl 2004;10:1441–1453.)
Abstract
Background
Transcatheter aortic valve implantation (TAVI) has revolutionised the treatment of severe aortic stenosis, but is still associated with a risk of major vascular complication.
Case ...summary
An elective transfemoral TAVI was undertaken for severe aortic stenosis. During delivery of a 26mm Sapien S3 valve, the delivery system sheath (eSheath) split prematurely. The valve could not be advanced, and lay parallel to the sheath body. Following advice, an attempt was made to remove the system en bloc but this was unsuccessful. After careful consideration of alternative options, the valve was advanced with reasonable force and the case was completed successfully. The femoral artery was closed with parclose sutures without major vascular complication.
Discussion
Early recognition of a split sheath with effective communication between lab team members and the manufacturer allowed us to successfully navigate this case, with a good outcome for our patient.
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