Rapid Progression Of Stenosis Research Articles

Invited commentary

Invited commentary

Vigencia de la endarterectomía carotídea para el tratamiento de estenosis asintomática en la era de las estatinas

The benefit of carotid endarterectomy in asymptomatic patients is currently questioned, due to an observed reduction in stroke rate with current medical treatment. A review is carried out on the available evidence.The perioperative use of statins, better standardisation of surgical techniques, concentration of endarterectomy by surgeons with a higher surgical volume, and identification of high-risk patients, have led to a parallel decrease in post-endarterectomy stroke. An asymptomatic subpopulation has been identified with an increased risk of developing neurological events: severe carotid stenosis, rapid progression of stenosis, presence of silent hemispherical infarcts, micro-emboli in transcranial doppler, lower cerebrovascular reserve, and unstable plaques.The future of carotid endarterectomy in asymptomatic patients lies in the identification of lesions with increased risk of stroke and performing surgery with minimal morbidity and mortality. Imaging studies have rapidly progress, but better validation is required before changing current management guidelines.

Gefäßscreening zur Schlaganfallprävention

The aim was to identify the risk of impending stroke originating from diseases of the carotid artery. Duplex scanning is the standard method for clinical examination of carotid arteries. By implementing the new standardized German Society for Ultrasound in Medicine (DEGUM) criteria, ultrasound examination enables reliable grading of carotid artery disease and identification of the progression of stenosis. Current guidelines recommend duplex scanning as the standard method. In consequence of finding atherosclerosis, intensive monitoring and therapy of cardiovascular risk factors is mandatory. In cases showing rapid progression of stenosis or a very high degree of stenosis indicating increased risk of stroke, carotid endarterectomy or stenting is warranted. Detection of carotid artery atherosclerosis is uncomplicated and the method is not demanding; however, identification of high-risk carotid disease by exact grading of carotid stenosis requires investigation by an experienced examiner. Screening is recommended for patients exhibiting cardiovascular risk factors but is not recommended for the general population. On detection of carotid stenosis an exact grading of stenosis by an experienced examiner is absolutely essential.

Rapid progression of coronary artery stenosis revealed by stress echocardiography

We present the case of a patient with initially insignifi cant coronary atherosclerosis with rapid progression revealed by dobutamine stress echocardiography, despite the absence of a major risk factor. A 61-year-old woman, complaining of chest pain, palpitations and dyspnoea on exertion, was referred to our department for outpatient assessment. Coronary angiography performed two months earlier revealed an insignifi cant stenosis of the proximal left anterior descending coronary artery. Holter monitoring revealed malignant ventricular arrhythmias during angina episodes. The results of maximal treadmill exercise testing were negative, but those of the dobutamine stress echocardiography were positive. The angiographic re-evaluation revealed a rapid progression of stenosis of the proximal left anterior descending coronary artery. Percutaneous coronary angioplasty with stenting was successfully performed. The outcome of patients with insignifi cant angiographic stenosis and no major risk factor is not necessarily favourable. Therefore, these patients should receive intensive therapy for the management of risk factors and careful clinical monitoring, including dobutamine stress echocardiography.

Intraleaflet haemorrhage as a mechanism of rapid progression of stenosis in bicuspid aortic valve

BackgroundThe mechanisms are unknown why aortic stenosis (AS) progresses faster in patients with bicuspid aortic valve (BAV) than those with tricuspid aortic valve (TAV). The objective of this study is to examine whether neoangiogenesis, haemorrhage in the aortic valve leaflet (intraleaflet haemorrhage) and macrophage infiltration are involved in the mechanisms of rapid progression of AS with BAV. MethodsWe retrospectively examined specimens of aortic valve leaflets obtained from patients who had undergone aortic valve replacement for AS (AS with BAV: n=22, AS with TAV: n=86). The stenotic valve leaflets were examined by immunohistochemistry to detect vascular endothelial cells, red blood cell remnant and macrophage. We assessed the progression of AS by annualized changes in the aortic valve area (ΔAVA: cm2/year) which was evaluated by serial echocardiography with the continuity equation. ResultsNeoangiogenesis, intraleaflet haemorrhage and macrophage infiltration were frequently observed in leaflets obtained from AS patients with BAV (neoangiogenesis: 82%, intraleaflet haemorrhage: 91%, macrophage infiltration 91%). These pathological changes were more severe in AS with BAV than TAV, and they were positively correlated with progression of AS in patients with BAV. Multivariated analysis revealed that bicuspid anatomy was the only factor that predicted neoangiogenesis, intraleaflet haemorrhage and macrophage infiltration when patients with BAV and those with TAV were combined. ConclusionsNeoangiogenesis, intraleaflet haemorrhage and macrophage infiltration are more severe in leaflets from AS with BAV than TAV and associated with rapid progression of AS with BAV. This pathological process may account for rapid progression of AS with BAV.

Revascularization of carotid artery stenosis - a brief update on current evidence

Major and long-awaited trials comparing carotid endarterectomy (CEA) with carotid stenting (CAS) were published in recent years. Both, ICSS and CREST, documented a higher rate of periprocedural stroke and death in CAS, in particular in elderly patients, thereby confirming the results of prior trials and meta-analyses. In CREST, the composite endpoint included myocardial infarction (MI), which led to statistical equipoise between the treatment arms due to a higher rate of MI with CEA. However, whether MI is a relevant endpoint in trials for stroke prevention remains debatable. The stroke preventive benefit seems equally sustained after CEA and CAS, although the significance of restenoses, whose frequency is twice as high after CAS compared to CEA, is unclear in the long range. Emergent CEA in patients with clinically unstable carotid stenosis is associated with a very high complication risk, but the optimal treatment strategy for these patients remains to be elucidated. Recent evidence indicates a very low stroke risk of asymptomatic stenoses with intensive medical treatment, rendering revascularization almost unnecessary. The detection of microembolic signals on transcranial Doppler and rapid stenosis progression by duplex sonography might help to identify patients with higher stroke risk in whom revascularization is warranted.

Asymptomatic central venous stenosis in hemodialysis patients

Conclusion: In patients with a hemodialysis access graft and an asymptomatic central venous stenosis (CVS) of >50%, treatment of the CVS results in more rapid stenosis progression compared with a nontreatment approach. Summary: The authors evaluated the natural history of >50% asymptomatic CVSs in hemodialysis patients. Outcome of serial treatment of CVS with percutaneous catheter-based techniques (PTA) was also evaluated. All patients in this study required maintenance procedures for their dialysis access. Between 1998 and 2004, 35 patients (19 men, 16 women), with a mean age of 58.7 years, were found to have asymptomatic CVS of >50%. CVS was measured by using venograms obtained before and after PTA. Patients with arm swelling, multiple CVSs, or indwelling catheters, were excluded. CVS progression was calculated by comparing degrees of stenoses with serial venographic examinations. The mean severity of CVSs before intervention was 71% (range, 50% to 100%), with 62% of lesions having associated collateral vessels. Twenty eight percent of CVSs were not treated. The mean degree of stenosis in the untreated group was 72% (range, 30% to 100%). Mean progression of stenosis in the untreated group was –0.8% point per day. No untreated CVS progressed to symptoms, stent placement, or developed additional CVS. PTA was used to treat 62 CVS lesions (72%). The mean degree of stenosis in the treated group was 74% (range, 50% to 100%) before and 40% (range, 0% to 75%) after treatment. In the treated group, mean progression of CVS was 0.21% per day after treatment. Six of the 62 treated CVS lesions were monitored, with symptomatic escalation of the CVS as manifested by arm swelling, need for stent placement, or development of additional CVS lesions. Comment: Treatment of an asymptomatic CVS in a dialysis patient is not a good thing. One is reminded of the old adage that it is wise to avoid poking a skunk. A major weakness of this study is that the patients were undergoing maintenance procedures for their dialysis access. We do not know if the CVS contributed to the need for the dialysis access maintenance. It would be interesting to know if there was a higher rate of repeat procedures for maintenance of dialysis access in patients with treated vs untreated CVS.

Asymptomatic Central Venous Stenosis in Hemodialysis Patients

To retrospectively evaluate the natural history of high-grade (>50%) asymptomatic central venous stenosis (CVS) in hemodialysis patients and the outcome of serial treatment of CVS with percutaneous transluminal angioplasty (PTA). The institutional review board granted exemption for this retrospective study, the need for informed consent was waived, and all data collection was in compliance with HIPAA. Patients with hemodialysis access requiring maintenance procedures between 1998 and 2004 and incidentally found to have ipsilateral (> or =50%) CVS were identified from a departmental database. Thirty-five patients (19 men, 16 women; mean age, 58.7 years) with 38 grafts met inclusion criteria, and 86 venograms were reviewed. CVS was measured by using venograms obtained before and after PTA, if performed. Patients with arm swelling, multiple CVS, indwelling catheters, and stents at the first encounter were excluded. CVS progression was calculated by dividing the change in the degree of stenosis by the time between venographic examinations. Wilcoxon rank sum test was used to evaluate differences in rate of CVS progression between treated and nontreated patients. Mean degree of CVS before intervention was 71% (range, 50%-100%). Sixty-two percent (53 of 86) of lesions had associated collateral vessels; 28% (24 of 86) of CVSs were not treated. Mean degree of stenosis in this group was 72% (range, 30%-100%); mean progression was -0.08 percentage point per day. No untreated CVS progressed to symptoms, stent placement, or additional CVS. Seventy-two percent (62 of 86) of CVSs were treated with PTA. Mean degree of stenosis in this group was 74% (range, 50%-100%) before and 40% (range, 0%-75%) after treatment; mean progression was 0.21 percentage point per day after treatment (P = .03). Six (8%) of 62 treatments were followed by CVS escalation; one patient developed arm swelling, four required stents, and four developed additional CVS. PTA of asymptomatic CVS greater than 50% in the setting of hemodialysis access maintenance procedures was associated with more rapid stenosis progression and escalation of lesions, compared with a nontreatment approach.

Increased plasma endothelin levels in angina patients with rapid coronary artery disease progression.

To investigate the association between plasma endothelin levels and rapid coronary artery disease progression, as assessed by quantitative angiography. Changes in diameter were assessed in 224 coronary stenoses of 92 consecutive patients (62 men) with chronic stable angina pectoris who were on a waiting list for routine coronary angioplasty and underwent coronary angiography on two occasions: the first (diagnostic) angiogram was carried out at study entry and the second 5.5+/-3.0 months later, immediately prior to coronary angioplasty. A digital quantitative angiographic analysis system was used to assess differences in stenosis diameter between the first and second angiogram. Plasma immunoreactive endothelin levels were estimated by radioimmunoassay at study entry. Rapid coronary artery disease progression occurred in 29 (31.5%) patients according to pre-established criteria: 12 (41%) had a > or =10% diameter reduction of at least one pre-existing stenosis > or =50%, 10 (34%) had a > or =30% diameter reduction of a pre-existing stenosis <50%, 5 (17%) patients developed a new stenosis and 2 (7%) had progression of a lesion to total occlusion by the second angiogram. Baseline demographic, clinical and angiographic data were similar in patients with and without stenosis progression. Plasma endothelin levels were significantly higher in patients with rapid disease progression than in those without (5.7+/-2.0 pg. ml(-1)vs 3.9+/-1.6 pg. ml(-1), P<0.001). Multiple logistic regression analysis revealed that endothelin was an independent predictor of disease progression (P=0.001). Moreover, endothelin levels above 4.26 pg. ml(-1)(the median of the total endothelin concentrations) were associated with a sixfold increase in the risk of developing rapid stenosis progression. Plasma endothelin is raised in patients with coronary artery disease progression and may be a marker of risk of rapid stenosis progression. Endothelin may also play a pathogenic role in this process.

Restenosis after coronary angioplasty for rapidly progressive coronary stenosis.

We hypothesized that percutaneous transluminal coronary angioplasty performed on coronary stenoses that have demonstrated rapid angiographic progression would be associated with a high risk of restenosis. High rates of restenosis have been documented after percutaneous transluminal coronary angioplasty of unstable lesions and of lesions that recur rapidly after a successful initial angioplasty. This suggests that the "activity' of the plaque at the time of angioplasty may be an important factor determining the risk of restenosis. In our institution we recommend angiographic follow-up for all patients with successful percutaneous transluminal coronary angioplasty. In this way we identified 86 consecutive patients who, at the time of angiographic follow-up had not developed restenosis at the dilated site, but required a further percutaneous transluminal coronary angioplasty at a different site. (which was successful). Based on quantitative angiographic measurements, 45 of these lesions (rapidly progressive lesions) had significantly increased in severity in the interval between the two angiograms (7.7 +/- 3.3 months) while 41 (stable lesions) had not. Rapid progression was defined as a > 0.4 mm decrease in minimal lumen diameter between initial angiography and percutaneous transluminal coronary angioplasty. All 86 patients had further angiographic follow-up 6 months later. Baseline clinical and angiographic variables were similar in both groups except that a higher proportion of patients in the rapid progression group had unstable angina (20% vs 5%; P < 0.05). Late loss during follow-up did not differ statistically between groups (0.31 mm) and minimal lumen diameter at follow-up was also similar (stable lesion group = 1.40 +/- 0.48 mm; rapidly progressive lesion group = 1.30 +/- 0.59 mm). The loss index (late loss divided by acute gain) was also similar in both groups (0.45 +/- 0.52 in the stable lesion group, 0.37 +/- 0.76 in the rapidly progressive lesion group). A strong correlation between acute gain and late loss was observed in the stable lesion group (r = 0.61; P < 0.0001); by contrast, there was no relationship between these two variables in the rapidly progressive lesion group (r = 0.20; P = 0.19). Percutaneous transluminal coronary angioplasty in patients with unstable angina or with early recurrence after a first percutaneous transluminal coronary angioplasty is associated with an increased risk of restenosis. By contrast, this study shows that angiographic instability, as evidenced by rapid stenosis progression, has no deleterious effect on the occurrence of restenosis. Percutaneous transluminal coronary angioplasty thus appears as a reasonable therapeutic option for coronary stenoses that have demonstrated rapid angiographic progression in the months prior to the procedure.