冠状动脉轻中度狭窄病变的血管内超声特征

通过分析病变的结构特点 ,探讨轻中度狭窄病变斑块不稳定的机制。对冠状动脉造影显示轻中度狭窄(直径狭窄率 2 0 %～ 6 0 % ) 6 2例及重度狭窄 2 6例冠心病患者行血管内超声显像检查 ,分析粥样硬化斑块性质及其狭窄程度。结果发现 ,轻中度狭窄患者中软斑块 (6 8.2 %比 15 .4 % ,P <0 .0 1)、薄纤维帽 (6 5 .9%比 7.7% ,P <0 .0 1)显著多于重度狭窄患者 ,并且斑块破裂 (2 8.2 %比 7.7% ,P <0 .0 1)及正性重构 (5 1.8%比 0 % ,P <0 .0 1)也显著多于重度狭窄患者。轻中度狭窄患者偏心斑块检出率显著多于重度狭窄者 (84 .7%比 30 .1% ,P <0 .0 1) ,但钙化少见 (16 .5 %比 84 .6 % ,P <0 .0 1)。结果提示 ,冠状动脉造影轻中度狭窄患者多数具有不稳定性斑块的结构特点 ,这些特点导致轻中度狭窄者容易发生急性冠状动脉综合征。     

In vivo tomographic assessment of the heart and blood vessels with intravascular ultrasound

Intravascular ultrasound (IVUS) has emerged from being a research tool to becoming an intrinsic part of modern invasive cardiology mainly due to imaging micro anatomy in vivo. For the first time, it is possible to base therapeutic decisions not only on lumenograms but also on vessel wall assessment. IVUS has both diagnostic and intervention associated potential. The diagnostic strength of IVUS is its ability to describe compensatory coronary artery enlargement as a response to arteriosclerosis, to assess intermediate lesions, and to reveal occult left main stem disease and angiographically “silent” arteriosclerosis. The intervention associated potential of IVUS is the optimal device selection, i.e., rotablators in calcified lesions or atherectomy devices in large plaque burden. The effects of PTCA on vessel wall morphology can be studied in great detail and the effect on luminal gain can be assessed. Several groups have shown that the residual plaque area (“plaque burden”) even after angiographically successful PTCA still lies in the range of 60%. A significant reduction in this number may influence long-term outcome after PTCA. Minimal luminal area and residual plaque area after PTCA seem to be indicators of restenosis, while the presence or absence of dissections seems to be less predictive. The main mechanism of restenosis after PTCA is vessel shrinkage, not intimal hyperplasia. Intravascular monitoring of stent expansion led to high-pressure stent deployment with a significant increase in post-procedural luminal diameters and the ability to withhold anticoagulation in patients with optimal stent deployment. In pulmonary and aortic diseases, IVUS contributed significantly to the understanding of aortic dissection and pulmonary hypertension. Additionally, with intracardiac ultrasound left and right ventricular function can be assessed. Intracardiac ultrasound has gained clinical usefulness for guiding transcatheter ablation in patients with conduction system abnormalities. In the future, integrated devices, such as balloons on IVUS catheters, steerable catheters, integrated flow and pressure transducers, tissue characterization, and 0.018” IVUS guide wires will further enhance the usefulness of IVUS. Received: 6 May 1997, Returned for revision: 4 July 1997, Revision received: 29 January 1998, Accepted: 17 February 1998     

The birth,decline, and contemporary re-emergence of endovascular brachytherapy for prevention of in-stent restenosis

Despite the advent of drug-eluting stents and dual antiplatelet therapy in the interventional management of cardiovascular disease, restenosis rates remain high with significant sequelae. Endovascular brachytherapy—popular in the 1990s and early 2000s—has recently resurfaced as a cost-effective treatment option. In this work, we outline the history of endovascular brachytherapy starting with its earliest promise in the 1990s. We discuss the development of drug-eluting stents and dual antiplatelet strategies and their impact on the perceived benefit of endovascular brachytherapy. For the contemporary era, we propose novel roles for endovascular brachytherapy in complex coronary artery disease and in high-risk patients managed with drug-eluting stents. We discuss the impetus for reducing the requirement and duration of dual antiplatelet therapy using endovascular brachytherapy. We also review innovative opportunities for endovascular brachytherapy after bare-metal stent placement in both coronary and noncoronary territories and offer economic arguments in favor of endovascular brachytherapy. Trials of endovascular brachytherapy in these regimes are merited.     

Hemodynamic Instability during Carotid Angioplasty and Stenting-Relationship of Calcified Plaque and Its Characteristics

Purpose

During carotid angioplasty and stenting (CAS), hemodynamic instability (HDI) can occur, possibly causing post-procedural ischemic complications. The goal of this study was to investigate the risk factors of HDI focusing on characteristics of plaque.

Materials and Methods

Thirty nine CAS patients were retrospectively evaluated for HDI. Prolonged HDI that lasted over 30 minutes was analyzed in relation to characteristics of calcified plaque.

Results

Nineteen (48.7%) patients had HDI. Ten of the 19 had both bradycardia and hypotension, and nine had only bradycardia. All bradycardia was treated well with a transcutaneous temporary cardiac pacemaker. But eight patients presented with prolonged hypotension in spite of recovery of bradycardia. Calcified plaque was a related factor associated with HDI (odds ratio, 8.571; 95% confidence interval, 1.321-55.62; p=0.024). Extensive and eccentric type calcified plaques were associated with prolonged hypotension (p=0.04, and p=0.028, respectively).

Conclusion

The calcification of plaque is a predictable factor of HDI during CAS, and its extensive and eccentric calcified plaques may be related to prolonged HDI.     

Microbiology of bile in extrahepatic biliary obstruction: A tropical experience

PurposeBile is considered sterile, but in obstructed biliary system, growth of micro-organisms results in bacteraemia and toxaemia. We analysed bacterial profile of patients undergoing endoscopic retrograde cholangiopancreatography (ERCP) and evaluated antibiotic resistance patterns to formulate strategy for antibiotics in patients undergoing ERCP.Materials and methodsPatients with cholestasis who underwent ERCP were enrolled. Bile, collected aseptically, was cultured. Positive cultures were processed for isolate identification and antibiotic susceptibility.ResultsOne hundred and sixty-three patients (78 females; mean age – 55.1 ± 15.8 years) were enrolled and divided into two groups: Group I (n = 99) were naïve and Group II (n = 64) had undergone ERCP and stenting previously. Positive culture was seen in 68.1% (n = 111) with monomicrobial growth in 74.8% (n = 83) and poly-microbial growth in 25.2% (n = 28). Culture positivity was common in Group II vis-a-vis Group I (84.4% vs. 57.5%). Poly-microbial growth was significantly more common in Group II (35.2% vs. 15.8%, P = 0.028). Gram-negative bacilli were the predominant organisms isolated with Escherichia coli, Pseudomonas aeruginosa and Klebsiella pneumoniae comprising 70% of the isolates. The most sensitive antibiotics were piperacillin-tazobactam and imipenem. The sensitivity of vancomycin, against Enterococcus spp. was in the range of 60%–70%.ConclusionCholestasis leads to bacterial colonisation in most cases, regardless of the presence of a biliary stent. Biliary stent however predisposes to a polymicrobial growth. Most of the commonly used antibiotics continue to have significant sensitivity and may be used empirically. However, previously stented patients may have a higher incidence of infection with Enterococcus spp. and may require specific therapy.     

Optimized strategy of rotational atherectomy of underexpanded coronary stents in patients with acute coronary syndrome

BACKGROUND: Stent under-expansion is a main cause of acute coronary syndrome (ACS), which can lead to serious clinical outcomes. The rotational atherectomy of underexpanded coronary stents (academically called stent ablation, SA) by intravascular ultrasound (IVUS) may provide more visual reference in the intervention. We aim to analyze the procedural and long-term outcomes of the optimized strategy of SA in patients with ACS and to provide real-world data on this technique.     

Cangrelor dose titration using platelet function testing during cerebrovascular stent placement

BackgroundOptimal antiplatelet inhibition is vital during cerebrovascular stenting procedures, yet no standardized recommendation exists for antithrombotic therapy in these scenarios. Cangrelor is an intravenous P2Y12 inhibitor with a favorable pharmacokinetic profile for use during neuroendovascular stenting.MethodsA retrospective review of all neuroendovascular patients who underwent stenting between 1 January 2019 and 22 March 2020 and were treated with cangrelor was conducted. Thirty-seven patients met inclusion criteria.ResultsAll patients were administered a bolus of 5 mcg/kg of cangrelor followed by a maintenance infusion. Antiplatelet effects of cangrelor were monitored using platelet reactivity units (PRU). Based on the initial PRU, seven patients’ doses were adjusted with subsequent PRUs in or near the goal range of 50–150. One patient experienced an acute intraprocedural occlusion likely related to a subtherapeutic PRU which subsequently resolved with cangrelor dose adjustment and intra-arterial tirofiban administration, and one patient experienced a post-procedure stent occlusion which required a thrombectomy and intra-arterial tirofiban administration. No hemorrhagic complications occurred.DiscussionCangrelor utilization during neuroendovascular stenting with maintenance doses of <2 mcg/kg/min with dose adjustments based on platelet function testing has not been previously described. Cangrelor presents many advantages compared to standard therapy in patients undergoing stent placement related to its pharmacokinetic profile, rapid onset of action, ease of transition to oral P2Y₁₂ antiplatelet agents, and measurability.ConclusionCangrelor is a promising alternative to currently available therapies, especially in patients with a high hemorrhagic risk.     

Venous sinus stenting for the treatment of isolated pulsatile tinnitus: Results of a prospective trial

ObjectivesThis prospective study evaluates the effectiveness and safety of venous sinus stenting for patients with isolated pulsatile tinnitus and lateral sinus stenosis.MethodsPatients with isolated pulsatile tinnitus and lateral sinus stenosis with a minimum trans stenotic gradient of 4 mm Hg were treated with stenting. Pulsatile tinnitus before and after treatment was assessed with the Tinnitus Handicap Inventory (THI). Periprocedural adverse events, neurological complications, clinical and radiographic follow-up were also recorded.ResultsA total of 42 patients (41 females and 1 male) were included in the study (median age of 37.5 years). Thirty patients had post-stenotic fusiform and 12 had post-stenotic saccular venous sinus aneurysm. In addition to stenting, coils were used to treat the patients with saccular venous aneurysms. The median follow-up was 5 months (range 1 to 34 months). Most patients had complete (39/42) or near-complete (2/42) resolution of their pulsatile tinnitus post-procedure. There were no serious adverse events.ConclusionStenting of the lateral venous sinus is a safe and effective treatment for patients with isolated pulsatile tinnitus due to venous sinus stenosis.     

Distal radial artery (snuffbox) access for carotid artery stenting – Technical pearls and procedural set-up

PurposeTo report use of distal radial artery (dRA) access for carotid artery stenting (CAS) and to discuss procedural setup and technical considerations for a successful intervention.MethodsA retrospective review of our prospective neurointerventional database of CAS was conducted between May 2019 and March 2020. All CAS cases via dRA in the anatomical snuffbox were identified. Patient demographics, clinical information, procedural and radiographic data was collected.Results22 CAS procedures in 20 patients via dRA were identified. Patients’ mean age was 69.4 years (range 53–87 years). 3 patients were female. Mean radial artery diameter was 2.1 mm (range 1.6–2.8 mm). dRA access was achieved in all cases. Conversion to femoral access was required in 2 cases (9.1%) due to persistent radial artery vasospasm resulting in patient discomfort despite multiple additional doses of intraarterial vasodilators and added intravenous sedation as well as tortuous vessel anatomy and limited support of the catheters in a type 3 aortic arch for left CAS.ConclusionOur preliminary experience with dRA access for CAS suggests this approach to be feasible and safe for patients. Technical considerations are important and preprocedural planning is necessary for a successful intervention. Catheter systems and devices specifically designed for radial access are needed to enable more interventionalists to safely perform neurointerventional procedures via wrist access.