Patient-Level Pooled Analysis of Endovascular Ultrasound Renal Denervation or a Sham Procedure 6 Months After Medication Escalation: The RADIANCE Clinical Trial Program

BACKGROUND

The randomized, sham-controlled RADIANCE-HTN (A Study of the Recor Medical Paradise System in Clinical Hypertension) SOLO, RADIANCE-HTN TRIO, and RADIANCE II (A Study of the Recor Medical Paradise System in Stage II Hypertension) trials independently met their primary end point of a greater reduction in daytime ambulatory systolic blood pressure (SBP) 2 months after ultrasound renal denervation (uRDN) in patients with hypertension. To characterize the longer-term effectiveness and safety of uRDN versus sham at 6 months, after the blinded addition of antihypertensive treatments (AHTs), we pooled individual patient data across these 3 similarly designed trials.

METHODS

Patients with mild to moderate hypertension who were not on AHT or with hypertension resistant to a standardized combination triple AHT were randomized to uRDN (n=293) versus sham (n=213); they were to remain off of added AHT throughout 2 months of follow-up unless specified blood pressure (BP) criteria were exceeded. In each trial, if monthly home BP was ≥135/85 mm Hg from 2 to 5 months, standardized AHT was sequentially added to target home BP <135/85 mm Hg under blinding to initial treatment assignment. Six-month outcomes included baseline- and AHT-adjusted change in daytime ambulatory, home, and office SBP; change in AHT; and safety. Linear mixed regression models using all BP measurements and change in AHT from baseline through 6 months were used.

RESULTS

Patients (70% men) were 54.1±9.3 years of age with a baseline daytime ambulatory/home/office SBP of 150.5±9.8/151.0±12.4/155.5±14.4 mm Hg, respectively. From 2 to 6 months, BP decreased in both groups with AHT titration, but fewer uRDN patients were prescribed AHT (P=0.004), and fewer additional AHT were prescribed to uRDN patients versus sham patients (P=0.001). Whereas the unadjusted between-group difference in daytime ambulatory SBP was similar at 6 months, the baseline and medication-adjusted between-group difference at 6 months was -3.0 mm Hg (95% CI, -5.7, -0.2; P=0.033), in favor of uRDN+AHT. For home and office SBP, the adjusted between-group differences in favor of uRDN+AHT over 6 months were -5.4 mm Hg (-6.8, -4.0; P<0.001) and -5.2 mm Hg (-7.1, -3.3; P<0.001), respectively. There was no heterogeneity between trials. Safety outcomes were few and did not differ between groups.

CONCLUSIONS

This individual patient-data analysis of 506 patients included in the RADIANCE trials demonstrates the maintenance of BP-lowering efficacy of uRDN versus sham at 6 months, with fewer added AHTs.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifiers: NCT02649426 and NCT03614260.

Systematic review of multiple versus single device closure of Secundum atrial septal defects in adults

INTRODUCTION

Multiple device closure (MDC) strategy has been used in treating of complex Atrial septal defects (ASDs) in adults. The safety profile of MDC compared to conventional single device closure (SDC) is unknown in this population. This report represents the first review examining the outcomes of single versus multiple device ASD closure in adults with ostium secundum defects.

METHODS

Literature databases and manual search from their inception until June 30th, 2017 followed the Preferred Reporting Items of Systemic Review and Meta-Analysis (PRISMA) guideline. Main outcomes are 1) overall complication incidence, 2) arrhythmia incidence, 3) residual shunt rate. Each outcome profile was pooled by MDC and SDC, respectively and chi-square analysis was applied to examine statistical significance between MDC and SDC strategies (two-sided and p < .050).

RESULTS

A total of 1806 + studies were initially screened, and 20 studies were finally selected (MDC group, 147 patients; SDC group, 1706 patients). There was no difference in overall complication incidence (χ2 = 1.269; p = .259) and arrhythmia incidence (χ2 = 0.325; p = .568) between MDC and SDC. There was no difference in residual shunt rate between the SDC (4.10 %; 70/1706) and MDC groups (6.80 %; 10/147; χ2 = 2.387; p = .122).

CONCLUSIONS

The outcomes of percutaneous multiple ASD closure (MDC) seem to be safe and effective as compared to conventional single ASD (SDC) closure in terms of device - related complications and technical success of the procedure. Prospective registry data and randomized trials are needed to determine the long-term outcomes of percutaneous ASD closure using MDC.

Patient-Level Pooled Analysis of Ultrasound Renal Denervation in the Sham-Controlled RADIANCE II, RADIANCE-HTN SOLO, and RADIANCE-HTN TRIO Trials

Importance

Ultrasound renal denervation (uRDN) was shown to lower blood pressure (BP) in patients with uncontrolled hypertension (HTN). Establishing the magnitude and consistency of the uRDN effect across the HTN spectrum is clinically important.

Objective

To characterize the effectiveness and safety of uRDN vs a sham procedure from individual patient-level pooled data across uRDN trials including either patients with mild to moderate HTN on a background of no medications or with HTN resistant to standardized triple-combination therapy.

Data Sources

A Study of the ReCor Medical Paradise System in Clinical Hypertension (RADIANCE-HTN SOLO and TRIO) and A Study of the ReCor Medical Paradise System in Stage II Hypertension (RADIANCE II) trials.

Study Selection

Trials with similar designs, standardized operational implementation (medication standardization and blinding of both patients and physicians to treatment assignment), and follow-up.

Data Extraction and Synthesis

Pooled analysis using individual patient-level data using linear regression models to compare uRDN with sham across the trials.

Main Outcomes and Measures

The primary outcome was baseline-adjusted change in 2-month daytime ambulatory systolic BP (dASBP) between groups.

Results

A total of 506 patients were randomized in the 3 studies (uRDN, 293; sham, 213; mean [SD] age, 54.1 [9.3]; 354 male [70.0%]). After a 1-month medication stabilization period, dASBP was similar between the groups (mean [SD], uRDN, 150.3 [9.2] mm Hg; sham, 150.8 [10.5] mm Hg). At 2 months, dASBP decreased by 8.5 mm Hg to mean (SD) 141.8 (13.8) mm Hg among patients treated with uRDN and by 2.9 mm Hg to 147.9 (14.6) mm Hg among patients treated with a sham procedure (mean difference, -5.9; 95% CI, -8.1 to -3.8 mm Hg; P < .001 in favor of uRDN). BP decreases from baseline with uRDN vs sham were consistent across trials and across BP parameters (office SBP: -10.4 mm Hg vs -3.4 mm Hg; mean difference, -6.4 mm Hg; 95% CI, -9.1 to -3.6 mm Hg; home SBP: -8.4 mm Hg vs -1.4 mm Hg; mean difference, -6.8 mm Hg; 95% CI, -8.7 to -4.9 mm Hg, respectively). The BP reductions with uRDN vs sham were consistent across prespecified subgroups. Independent predictors of a larger BP response to uRDN were higher baseline BP and heart rate and the presence of orthostatic hypertension. No differences in early safety end points were observed between groups.

Conclusions and Relevance

Results of this patient-level pooled analysis suggest that BP reductions with uRDN were consistent across HTN severity in sham-controlled trials designed with a 2-month primary end point to standardize medications across randomized groups.

Trial Registration

ClinicalTrials.gov Identifier: NCT02649426 and NCT03614260.

Endovascular Ultrasound Renal Denervation to Treat Hypertension: The RADIANCE II Randomized Clinical Trial

Importance

Two initial sham-controlled trials demonstrated that ultrasound renal denervation decreases blood pressure (BP) in patients with mild to moderate hypertension and hypertension that is resistant to treatment.

Objective

To study the efficacy and safety of ultrasound renal denervation without the confounding influence of antihypertensive medications in patients with hypertension.

Design, Setting, and Participants

Sham-controlled, randomized clinical trial with patients and outcome assessors blinded to treatment assignment that was conducted between January 14, 2019, and March 25, 2022, at 37 centers in the US and 24 centers in Europe, with randomization stratified by center. Patients aged 18 years to 75 years with hypertension (seated office systolic BP [SBP] ≥140 mm Hg and diastolic BP [DBP] ≥90 mm Hg despite taking up to 2 antihypertensive medications) were eligible if they had an ambulatory SBP/DBP of 135/85 mm Hg or greater and an SBP/DBP less than 170/105 mm Hg after a 4-week washout of their medications. Patients with an estimated glomerular filtration rate of 40 mL/min/1.73 m2 or greater and with suitable renal artery anatomy were randomized 2:1 to undergo ultrasound renal denervation or a sham procedure. Patients were to abstain from antihypertensive medications until the 2-month follow-up unless prespecified BP criteria were exceeded and were associated with clinical symptoms.

Interventions

Ultrasound renal denervation vs a sham procedure.

Main Outcomes and Measures

The primary efficacy outcome was the mean change in daytime ambulatory SBP at 2 months. The primary safety composite outcome of major adverse events included death, kidney failure, and major embolic, vascular, cardiovascular, cerebrovascular, and hypertensive events at 30 days and renal artery stenosis greater than 70% detected at 6 months. The secondary outcomes included mean change in 24-hour ambulatory SBP, home SBP, office SBP, and all DBP parameters at 2 months.

Results

Among 1038 eligible patients, 150 were randomized to ultrasound renal denervation and 74 to a sham procedure (mean age, 55 years [SD, 9.3 years]; 28.6% female; and 16.1% self-identified as Black or African American). The reduction in daytime ambulatory SBP was greater with ultrasound renal denervation (mean, -7.9 mm Hg [SD, 11.6 mm Hg]) vs the sham procedure (mean, -1.8 mm Hg [SD, 9.5 mm Hg]) (baseline-adjusted between-group difference, -6.3 mm Hg [95% CI, -9.3 to -3.2 mm Hg], P < .001), with a consistent effect of ultrasound renal denervation throughout the 24-hour circadian cycle. Among 7 secondary BP outcomes, 6 were significantly improved with ultrasound renal denervation vs the sham procedure. No major adverse events were reported in either group.

Conclusions and Relevance

In patients with hypertension, ultrasound renal denervation reduced daytime ambulatory SBP at 2 months in the absence of antihypertensive medications vs a sham procedure without postprocedural major adverse events.

Trial Registration

ClinicalTrials.gov Identifier: NCT03614260.

Effects of Renal Denervation vs Sham in Resistant Hypertension After Medication Escalation: Prespecified Analysis at 6 Months of the RADIANCE-HTN TRIO Randomized Clinical Trial

Importance

Although early trials of endovascular renal denervation (RDN) for patients with resistant hypertension (RHTN) reported inconsistent results, ultrasound RDN (uRDN) was found to decrease blood pressure (BP) vs sham at 2 months in patients with RHTN taking stable background medications in the Study of the ReCor Medical Paradise System in Clinical Hypertension (RADIANCE-HTN TRIO) trial.

Objectives

To report the prespecified analysis of the persistence of the BP effects and safety of uRDN vs sham at 6 months in conjunction with escalating antihypertensive medications.

Design, Setting, and Participants

This randomized, sham-controlled, clinical trial with outcome assessors and patients blinded to treatment assignment, enrolled patients from March 11, 2016, to March 13, 2020. This was an international, multicenter study conducted in the US and Europe. Participants with daytime ambulatory BP of 135/85 mm Hg or higher after 4 weeks of single-pill triple-combination treatment (angiotensin-receptor blocker, calcium channel blocker, and thiazide diuretic) with estimated glomerular filtration rate (eGFR) of 40 mL/min/1.73 m2 or greater were randomly assigned to uRDN or sham with medications unchanged through 2 months. From 2 to 5 months, if monthly home BP was 135/85 mm Hg or higher, standardized stepped-care antihypertensive treatment starting with aldosterone antagonists was initiated under blinding to treatment assignment.

Interventions

uRDN vs sham procedure in conjunction with added medications to target BP control.

Main Outcomes and Measures

Six-month change in medications, change in daytime ambulatory systolic BP, change in home systolic BP adjusted for baseline BP and medications, and safety.

Results

A total of 65 of 69 participants in the uRDN group and 64 of 67 participants in the sham group (mean [SD] age, 52.4 [8.3] years; 104 male [80.6%]) with a mean (SD) eGFR of 81.5 (22.8) mL/min/1.73 m2 had 6-month daytime ambulatory BP measurements. Fewer medications were added in the uRDN group (mean [SD], 0.7 [1.0] medications) vs sham (mean [SD], 1.1 [1.1] medications; P = .045) and fewer patients in the uRDN group received aldosterone antagonists at 6 months (26 of 65 [40.0%] vs 39 of 64 [60.9%]; P = .02). Despite less intensive standardized stepped-care antihypertensive treatment, mean (SD) daytime ambulatory BP at 6 months was 138.3 (15.1) mm Hg with uRDN vs 139.0 (14.3) mm Hg with sham (additional decreases of -2.4 [16.6] vs -7.0 [16.7] mm Hg from month 2, respectively), whereas home SBP was lowered to a greater extent with uRDN by 4.3 mm Hg (95% CI, 0.5-8.1 mm Hg; P = .03) in a mixed model adjusting for baseline and number of medications. Adverse events were infrequent and similar between groups.

Conclusions and Relevance

In this study, in patients with RHTN initially randomly assigned to uRDN or a sham procedure and who had persistent elevation of BP at 2 months after the procedure, standardized stepped-care antihypertensive treatment escalation resulted in similar BP reduction in both groups at 6 months, with fewer additional medications required in the uRDN group.

Trial Registration

ClinicalTrials.gov Identifier: NCT02649426.

Vertebral artery stenosis

Symptomatic vertebral artery stenosis is associated with high risk of early recurrent stroke. Vertebral artery stenosis can be treated with angioplasty and stenting with good technical results. In this review we outline the framework for the diagnosis and management of vertebral artery disease with focus on the emerging benefits of angiography and endovascular interventions.

Novel Göttingen Miniswine Model of Heart Failure With Preserved Ejection Fraction Integrating Multiple Comorbidities

A lack of preclinical large animal models of heart failure with preserved ejection fraction (HFpEF) that recapitulate this comorbid-laden syndrome has led to the inability to tease out mechanistic insights and to test novel therapeutic strategies. This study developed a large animal model that integrated multiple comorbid determinants of HFpEF in a miniswine breed that exhibited sensitivity to obesity, metabolic syndrome, and vascular disease with overt clinical signs of heart failure. The combination of a Western diet and 11-deoxycorticosterone acetate salt-induced hypertension in the Göttingen miniswine led to the development of a novel large animal model of HFpEF that exhibited multiorgan involvement and a full spectrum of comorbidities associated with human HFpEF.

Elective Percutaneous Paravalvular Leak Closure Under Conscious Sedation: Procedural Techniques and Clinical Outcomes

BACKGROUND

Paravalvular leaks (PVLs) are a well-recognized complication of prosthetic valves that are detected up to 18% of all implanted surgical valves. Perioperative morbidity is thought to be lower in percutaneous compared to surgical PVL repair. However, a direct comparison of PVL closure techniques has never been performed. Our study is the first to demonstrate that elective PVL closure with monitored anesthesia care can be achieved with high success and low complications rates resulting in short hospital stays.

METHODS

This is a retrospective cohort of patients admitted electively for catheter-based treatment of symptomatic prosthetic paravalvular regurgitation from Jan 2013 to April 2018. Both mitral and aortic PVLs were included. Patients' demographics, risk factors, procedural outcomes, In-hospital and thirty-day mortality were all reported. We followed the Valve Academic Research Consortium (VARC) criteria to define device and procedural technical success. In-hospital and 30- day outcomes were assessed by retrospective chart review.

RESULTS

A total of 54 PVLs in thirty-seven patients were repaired (65% aortic & 35% mitral). The mean-age in the mitral cohort was lower than the aortic cohort (61 vs 72years, P<0.0001) but the two groups shared similar clinical risk factors (P>0.05). Average hospital stay was 1-2days (<1.5days overall cohort) which was significantly lower in the aortic compared to the mitral cohort (P=0.009). All procedures were guided by TEE under conscious sedation with monitored anesthesia care. Procedural technical success defined as any significant residual shunt was 81% in the overall cohort and 88% in the aortic group. No procedural deaths were reported. Short-term mortality during the first 30days was 5.4% (two patients).

CONCLUSION

Elective catheter-based repair of symptomatic prosthetic paravalvular regurgitation appears to be safe and effective. The use of conscious sedation with monitored anesthesia care resulted in short hospital stay.

A multiplanet system of super-Earths orbiting the brightest red dwarf star GJ 887

The closet exoplanets to the Sun provide opportunities for detailed characterization of planets outside the Solar System. We report the discovery, using radial velocity measurements, of a compact multiplanet system of super-Earth exoplanets orbiting the nearby red dwarf star GJ 887. The two planets have orbital periods of 9.3 and 21.8 days. Assuming an Earth-like albedo, the equilibrium temperature of the 21.8-day planet is ~350 kelvin. The planets are interior to, but close to the inner edge of, the liquid-water habitable zone. We also detect an unconfirmed signal with a period of ~50 days, which could correspond to a third super-Earth in a more temperate orbit. Our observations show that GJ 887 has photometric variability below 500 parts per million, which is unusually quiet for a red dwarf.

Renal denervation: Alternative treatment options for hypertension?

Hypertension affects millions of Americans and has adverse long-term consequences increasing morbidity and mortality. Resistant hypertension (RH) continues to be difficult to treat with medications alone which may be associated with significant side effects. Alternate therapies have been evaluated for treating RH and renal denervation has been investigated extensively. We review the data from renal denervation trials and other novel technologies which are not FDA approved to date.

Renal Denervation Prevents Heart Failure Progression Via Inhibition of the Renin-Angiotensin System

BACKGROUND

Previously, we have shown that radiofrequency (RF) renal denervation (RDN) reduces myocardial infarct size in a rat model of acute myocardial infarction (MI) and improves left ventricular (LV) function and vascular reactivity in the setting of heart failure following MI.

OBJECTIVES

The authors investigated the therapeutic efficacy of RF-RDN in a clinically relevant normotensive swine model of heart failure with reduced ejection fraction (HFrEF).

METHODS

Yucatan miniswine underwent 75 min of left anterior descending coronary artery balloon occlusion to induce MI followed by reperfusion (R) for 18 weeks. Cardiac function was assessed pre- and post-MI/R by transthoracic echocardiography and every 3 weeks for 18 weeks. HFrEF was classified by an LV ejection fraction <40%. Animals who met inclusion criteria were randomized to receive bilateral RF-RDN (n = 10) treatment or sham-RDN (n = 11) at 6 weeks post-MI/R using an RF-RDN catheter.

RESULTS

RF-RDN therapy resulted in significant reductions in renal norepinephrine content and circulating angiotensin I and II. RF-RDN significantly increased circulating B-type natriuretic peptide levels. Following RF-RDN, LV end-systolic volume was significantly reduced when compared with sham-treated animals, leading to a marked and sustained improvement in LV ejection fraction. Furthermore, RF-RDN improved LV longitudinal strain. Simultaneously, RF-RDN reduced LV fibrosis and improved coronary artery responses to vasodilators.

CONCLUSIONS

RF-RDN provides a novel therapeutic strategy to reduce renal sympathetic activity, inhibit the renin-angiotensin system, increase circulating B-type natriuretic peptide levels, attenuate LV fibrosis, and improve left ventricular performance and coronary vascular function. These cardioprotective mechanisms synergize to halt the progression of HFrEF following MI/R in a clinically relevant model system.

Non-arrhythmic causes of sudden death: A comprehensive review

Sudden cardiac death (SCD) is a major public health issue in the United States and worldwide. It is estimated to affect between 1 and 1.5 million patients worldwide annually, with the global burden expected to rise due to the concomitant rise in coronary artery disease in the developing world. Although arrhythmic causes of SCD such as ventricular tachycardia and ventricular fibrillation are common and well-studied, non-arrhythmic causes are also important, with diverse etiologies from ischemia-related structural heart disease to non-ischemic heart diseases, non-atherosclerotic coronary pathologies, and inflammatory states. Recent research has also found that risk factors and/or demographics predispose certain individuals to a higher risk of non-arrhythmia-related SCD. This review discusses the epidemiology, mechanisms, etiologies, and management of non-arrhythmic SCD.

Effects of a novel hydrogen sulfide prodrug in a porcine model of acute limb ischemia

OBJECTIVE

Previous studies have shown that hydrogen sulfide (H₂S) exerts potent proangiogenic properties under in vitro conditions and in rodent models. We sought to determine whether a novel H₂S prodrug promotes peripheral revascularization in a swine model of acute limb ischemia (ALI).

METHODS

ALI was induced in 17 female miniswine via intravascular occlusion of the external iliac. At day 7 after ALI induction, miniswine (n = 17) were randomized to received placebo or the H₂S prodrug, SG-1002 (800 mg per os twice a day), for 35 days. At day 35 SG-1002 increased circulating levels of H₂S (5.0 ± 1.2 μmol/L vs 1.8 ± 0.50 μmol/L; P < .05), sulfane sulfur (10.6 ± 2.3 μmol/L vs 2.6 ± 0.8 μmol/L; P < .05), and nitrite (0.5 ± 0.05 μmol/L vs 0.3 ± 0.03 μmol/L; P < .005) compared with placebo. SG-1002 therapy increased angiographic scoring in ischemic limb vessel number (27.6 ± 1.6 vs 22.2 ± 1.8; P < .05) compared with placebo. Treatment with SG-1002 preserved existing capillaries in ischemic limbs (128.3 ± 18.7 capillaries/mm² vs 79.0 ± 9.8 capillaries/mm²; P < .05) compared with placebo. Interestingly, treatment with SG-1002 also improved coronary vasorelaxation responses to bradykinin and substance P in miniswine with ALI.

CONCLUSIONS

Our results suggest that daily administration of the H₂S prodrug, SG-1002, leads to an increase in circulating H₂S and nitric oxide signaling and preserves vessel number and density in ischemic limbs. Furthermore, SG-1002 therapy improved endothelial-dependent coronary artery vasorelaxation in the setting of ALI. Our data demonstrate that SG-1002 preserves the vascular architecture in ischemic limbs and exerts vascular protective effects in the coronary vasculature in a model of peripheral vascular disease.

Effects of Arginine Vasopressin (AVP) Infusions on Circulating Concentrations of Platelet AVP, Factor VIII: C and von Willebrand Factor

To study the possible role of arginine vasopressin (AVP) in the control of haemostasis AVP infusions at 3 doses (0.1, 0.2 and 0.3 mU/kg/min) were performed in 6 male volunteers. Both plasma and platelet AVP concentrations rose in a dose-related manner. At doses of 0.2 and 0.3 mU/kg/min there was an increase in the plasma concentrations of both plasma Factor VIII and von Willebrand factor. The data support the hypothesis that AVP, by interacting with platelets and stimulating factor VIII and von Willebrand factor release, plays a role in the control of haemostasis.

Zofenopril Protects Against Myocardial Ischemia-Reperfusion Injury by Increasing Nitric Oxide and Hydrogen Sulfide Bioavailability

Background

Zofenopril, a sulfhydrylated angiotensin‐converting enzyme inhibitor (ACEI), reduces mortality and morbidity in infarcted patients to a greater extent than do other ACEIs. Zofenopril is a unique ACEI that has been shown to increase hydrogen sulfide (H₂S) bioavailability and nitric oxide (NO) levels via bradykinin‐dependent signaling. Both H₂S and NO exert cytoprotective and antioxidant effects. We examined zofenopril effects on H₂S and NO bioavailability and cardiac damage in murine and swine models of myocardial ischemia/reperfusion (I/R) injury.

Methods and Results

Zofenopril (10 mg/kg PO) was administered for 1, 8, and 24 hours to establish optimal dosing in mice. Myocardial and plasma H₂S and NO levels were measured along with the levels of H₂S and NO enzymes (cystathionine β‐synthase, cystathionine γ‐lyase, 3‐mercaptopyruvate sulfur transferase, and endothelial nitric oxide synthase). Mice received 8 hours of zofenopril or vehicle pretreatment followed by 45 minutes of ischemia and 24 hours of reperfusion. Pigs received placebo or zofenopril (30 mg/daily orally) 7 days before 75 minutes of ischemia and 48 hours of reperfusion. Zofenopril significantly augmented both plasma and myocardial H₂S and NO levels in mice and plasma H₂S (sulfane sulfur) in pigs. Cystathionine β‐synthase, cystathionine γ‐lyase, 3‐mercaptopyruvate sulfur transferase, and total endothelial nitric oxide synthase levels were unaltered, while phospho‐endothelial nitric oxide synthase¹¹⁷⁷ was significantly increased in mice. Pretreatment with zofenopril significantly reduced myocardial infarct size and cardiac troponin I levels after I/R injury in both mice and swine. Zofenopril also significantly preserved ischemic zone endocardial blood flow at reperfusion in pigs after I/R.

Conclusions

Zofenopril‐mediated cardioprotection during I/R is associated with an increase in H₂S and NO signaling.

Vascular brachytherapy versus drug-eluting stents in the treatment of in-stent restenosis: A meta-analysis of long-term outcomes

INTRODUCTION

Clinical trials have shown a short-term benefit of drug-eluting stents (DES) compared to vascular brachytherapy (VBT) for treatment of in-stent restenosis (ISR). The long-term benefits of DES vs. VBT are conflicting in the literature. This study aimed to do a meta-analysis of long-term outcomes of DES compared to VBT for treatment of ISR.

METHODS

PubMed, EMBASE, Cochrane Central and unpublished data were searched for cohort studies and randomized controlled trials (RCTs) that directly compared VBT to DES for the treatment of ISR. We evaluated the following outcomes at 2-5 years of follow-up: target lesion revascularization (TLR), target vessel revascularization (TVR), myocardial infarction (MI), stent thrombosis, cardiovascular (CV) mortality, and overall mortality. Heterogeneity was defined as I(2) values > 25%. Review Manager 5.1 was used for statistical analysis.

RESULTS

We included 1,375 patients from five studies, of which three were RCTs. VBT was used to treat ISR in 685 (49.8%) patients. After a 2-5 year follow-up, no significant differences were found between treatment groups regarding MI (P = 0.49), stent thrombosis (P = 0.86), CV mortality (P = 0.35), and overall mortality (P = 0.71). TLR (OR 2.37; CI 1.55-3.63; P < 0.001) and TVR (OR 2.23; CI 1.01-4.94; P = 0.05) were significantly increased in patients who received VBT.

CONCLUSION

This study suggests that DES are associated with decreased long-term revascularization procedures when compared to VBT for the treatment of ISR. This benefit does not appear to be associated with a significant reduction in mortality or myocardial infarction.

The Evolving Role of Percutaneous Mitral Valve Repair

BACKGROUND

Mitral regurgitation (MR) is the second leading cause of valvular heart disease in the United States behind aortic stenosis. The percutaneous repair of the mitral valve (MitraClip, Abbott, Inc.) has been approved in the United States since 2013 as an alternative to traditional mitral valve surgery. However, many questions are left unanswered about when to perform this procedure and whom to perform it on.

METHODS

We reviewed major published literature on the MitraClip from 2003-2016 to help guide clinical decision-making. A PubMed search was conducted using the phrase "mitraclip" or "percutaneous mitral valve repair" to identify relevant articles pertaining to the clip as well as surgical valve repair.

RESULTS

The clinical trials EVEREST I and EVEREST II (Endovascular Valve Edge-to-Edge Repair Study) demonstrated the safety and efficacy of the MitraClip but did not prove its superiority to surgical repair in the population studied. Numerous subsequent registries have suggested that the success of the MitraClip varies with the patient population studied. The currently enrolling Cardiovascular Outcomes for Assessment of the MitraClip Percutaneous Therapy for Heart Failure Patients with Functional MR (COAPT) trial hopes to answer some of these questions.

CONCLUSION

The MitraClip is a new and exciting technology for percutaneously treating disease processes traditionally managed with surgery. The future of the clip and its patient population is dependent on further studies.

Cilostazol increases patency and reduces adverse outcomes in percutaneous femoropopliteal revascularisation: a meta-analysis of randomised controlled trials

Background

Cilostazol is an oral antiplatelet agent currently indicated for treatment of intermittent claudication. There is evidence that cilostazol may reduce femoropopliteal restenosis after percutaneous endovascular intervention.

Methods

We searched PubMed, Scopus and Cochrane databases from 1966 through September 2013 for randomised controlled trials (RCTs) evaluating the addition of cilostazol to standard care in patients receiving femoropopliteal endovascular treatment. Restenosis, target lesion revascularisation and combined adverse outcomes (death, revascularisation and amputation) within 1–2 years postprocedure were evaluated.

Results

Of 205 articles, three RCTs were included in the analysis. The pooled data provided a total of 396 patients, 195 of whom received cilostazol. When compared to standard medical therapy alone, cilostazol significantly reduced the risk of restenosis (risk difference −0.20; 95% CI −0.29 to −0.11; p<0.0001; number needed to treat 5), target lesion revascularisation (risk difference −0.17; 95% CI −0.25 to −0.09; p<0.0001; number needed to treat 6). Death and amputation were not different in between groups.

Conclusions and limitation

Cilostazol significantly increases femoropopliteal patency and decreases adverse outcomes in percutaneous endovascular intervention. However, further RCTs are needed because of limited sample size; this meta-analysis represents the best current evidence.

Percutaneous Treatment of Vertebral Artery Stenosis

Endovascular treatment of the ostial and proximal portions of the vertebral artery is a safe and effective technique for alleviating symptoms and improving cerebral blood flow to the posterior circulation. Vertebral artery angioplasty can be performed with high technical and clinical success rates, low complication rates, and durable long-term results. Although restenosis rates range from 0% to 48%, the durability of vertebral artery angioplasty is evidenced by low restenosis rates in multiple large series reported in the literature using multiple treatment options, including balloon angioplasty alone, bare metal stents, and drug-coated stents.

Deep Venous Thrombosis: An Interventionalist's Approach

BACKGROUND

Deep venous thrombosis (DVT) of the lower extremity has traditionally been anatomically categorized into proximal DVT (thrombosis involving the popliteal vein and above) and distal DVT (isolated calf vein thrombosis). Proximal DVT involving the common femoral and/or iliac veins, referred to as iliofemoral DVT (IFDVT), represents a disease process with a worse prognosis and higher risk for poor clinical outcomes compared to proximal DVT not involving the common femoral or iliac draining veins.

METHODS

This review discusses therapeutic options for treatment of lower extremity IFDVT, including adjuvant anticoagulation and catheter-based invasive therapies; literature supporting current acute interventional techniques; and the recommendations from the recently published American Heart Association guidelines.

RESULTS

Patients with IFDVT represent an opportune subset of patients for acute interventional management with currently available techniques. This subset of patients with proximal DVT has a worse prognosis, is less well studied, and benefits more from acute intervention compared to patients with proximal DVT or distal DVT.

CONCLUSION

Invasive catheter-based therapies that remove thrombus and correct venous outflow obstructions improve outcomes and morbidity in patients with IFDVT. Future trials that address IFDVT specifically will improve our understanding and the proper management of this higher-risk subset of patients with DVT.

Carotid artery stenting: patient, lesion, and procedural characteristics that increase procedural complications

From the earliest experiences with carotid artery stenting (CAS) presumptive high risk features have included thrombus-containing lesions, heavily calcified lesions, very tortuous vessels, and near occlusions. In addition patients have been routinely excluded from CAS trials if they have contra-indications to dual antiplatelet therapy (aspirin and thienopyridines), a history of bleeding complications and severe peripheral arterial disease (PAD) making femoral artery vascular access difficult. Variables that increase the risk of CAS complications can be attributed to patient characteristics, anatomic or lesion features, and procedural factors. Clinical features such as older age (≥80 years), decreased cerebral reserve (dementia, multiple prior strokes, or intracranial microangiopathy) and angiographic characteristics such as excessive tortuosity (more than two 90° bends within 5 cm of the target lesion) and heavy calcification (concentric calcification ≥ 3 mm in width) have been associated with increased CAS complications. Other high risk CAS features include those that prolong catheter or guide wire manipulation in the aortic arch, make crossing a carotid stenosis more difficult, decrease the likelihood of successful deployment or retrieval of an embolic protection device (EPD), or make stent delivery or placement more difficult. Procedure volume for the operator and the catheterization laboratory team are critical elements in reducing the risk of the procedure. In this article, we help CAS operators better understand procedure risk to allow more intelligent case selection, further improving the outcomes of this emerging procedure.

Effect of angiotensin-converting enzyme inhibitor on response of plasma renin activity and aldosterone to tilting in man

1 The effect of an angiotensin-converting enzyme inhibitor (SQ 20,881; 0.5 mg/kg) on the response to tilting of plasma renin activity (PRA), plasma aldosterone and cortisol was studied in five normal subjects. 2 PRA rose significantly in both the supine and upright positions following administration of SQ 20,881; no significant effect on aldosterone or cortisol was observed.

Factors related to a clinically silent peri-procedural drop in hemoglobin with coronary and peripheral vascular interventions

Clinically evident and subclinical peri-procedural bleeding following interventional therapies are associated with adverse cardiovascular outcomes. The risk factors for clinically evident bleeding have been well described. Despite the well-documented association of adverse outcomes for patients with a subclinical peri-procedural hemoglobin drop, the clinical predictors have not yet been defined. We identified 1176 consecutive patients with a subclinical drop in hemoglobin (fall of ≥ 1 g/dl in patients without clinical bleeding) following percutaneous coronary interventions (PCI) and peripheral vascular interventions (PVI). Multivariate logistic regression analysis was performed. A subclinical peri-procedural hemoglobin drop ≥ 1 g/dl was identified in 41% (400/972) of PCI and in 49% (213/435) of PVI. More than one access site predicted a higher risk of a subclinical drop in hemoglobin in both groups. A body mass index ≥ 30 predicted a lower risk of a subclinical drop in hemoglobin in both groups. For PCI, creatinine clearance < 60 ml/min was associated with a higher risk of a subclinical drop in hemoglobin. In conclusion, clinically silent peri-procedural hemoglobin fall ≥ 1 g/dl is common in patients undergoing both coronary and peripheral percutaneous intervention. Predictors identified in our study will need prospective validation.

Catheter-based therapy of common femoral artery atherosclerotic disease

The objective of this paper is to describe outcomes of endovascular therapy in patients with symptomatic common femoral artery (CFA) lesions. Symptomatic atherosclerotic disease of the common femoral artery is an uncommon clinical entity, and there is no consensus regarding the suitability of catheter-based therapy. We reviewed the records of 26 consecutive patients treated with catheter-based therapy for symptomatic CFA lesions between 1994 and 2009. Angiographic success and procedure success were obtained in all vessels and in all patients. At 1 year, 100% (16/16) of the claudication patients and 70% (7/10) of the critical limb ischemia (CLI) patients maintained clinical success. The ankle— brachial index (ABI) significantly improved from a baseline of 0.47 ± 0.18 to 0.77 ± 0.18 ( p < 0.001) after the procedure. At their most recent clinic visit (31 months ± 14 months), clinical success was maintained in 100% of the claudication patients and in 70% (7/10) of the CLI patients. During the follow-up period, femoral vascular access for an unrelated procedure was obtained through the CFA stent. In conclusion, patients with symptomatic CFA atherosclerotic disease obtained excellent clinical outcomes with angioplasty with stenting. We found that angioplasty with stenting of the CFA did not preclude future CFA vascular access. Our data suggest that catheter-based therapies should be considered as an option to open surgery in selected patients with symptomatic CFA disease.

Management of massive and submassive pulmonary embolism, iliofemoral deep vein thrombosis, and chronic thromboembolic pulmonary hypertension: a scientific statement from the American Heart Association

Venous thromboembolism (VTE) is responsible for the hospitalization of >250 000 Americans annually and represents a significant risk for morbidity and mortality. Despite the publication of evidence-based clinical practice guidelines to aid in the management of VTE in its acute and chronic forms, the clinician is frequently confronted with manifestations of VTE for which data are sparse and optimal management is unclear. In particular, the optimal use of advanced therapies for acute VTE, including thrombolysis and catheter-based therapies, remains uncertain. This report addresses the management of massive and submassive pulmonary embolism (PE), iliofemoral deep vein thrombosis (IFDVT),and chronic thromboembolic pulmonary hypertension (CTEPH). The goal is to provide practical advice to enable the busy clinician to optimize the management of patients with these severe manifestations of VTE. Although this document makes recommendations for management, optimal medical decisions must incorporate other factors, including patient wishes, quality of life, and life expectancy based on age and comorbidities. The appropriateness of these recommendations for a specific patient may vary depending on these factors and will be best judged by the bedside clinician.

Endovascular stenting for vertebral artery stenosis

OBJECTIVES

The aim of this study was to demonstrate the safety and long-term durability of catheter-based therapy for symptomatic vertebral artery stenosis (VAS).

BACKGROUND

Symptomatic VAS carries with it a 5-year 30% to 35% risk of stroke. The 2-year mortality approaches 30% for medically managed strokes involving the posterior circulation. Surgical bypass is rarely performed, due to high morbidity and mortality. Endovascular revascularization with primary stenting offers an attractive treatment option for these patients.

METHODS

One-hundred five consecutive symptomatic patients (112 arteries, 71% male) underwent stent placement for extracranial (91%) and intracranial (9%) VAS from 1995 to 2006. Fifty-seven patients (54%) had bilateral VAS, 71 patients (68%) had concomitant carotid disease, and 43 patients (41%) had a prior stroke.

RESULTS

Procedural and clinical success was achieved in 105 (100%) and 95 (90.5%) patients, respectively. One-year follow-up was obtained in 87 (82.9%) patients, of which 69 patients (79.3%) remained symptom-free. At 1 year, 6 patients (5.7%) had died and 5 patients (5%) had a posterior circulation stroke. Target vessel revascularization occurred in 7.4% at 1 year. At a median follow-up of 29.1 months (interquartile range 12.8 to 50.9 months), 13.1% underwent target vessel revascularization, 71.4% were alive, and 70.5% remained symptom-free.

CONCLUSIONS

In experienced hands, stenting for symptomatic VAS can be accomplished with a very high success rate (100%), with few periprocedural complications, and is associated with durable symptom resolution in the majority (approximately 80%) of patients. We conclude that endovascular stenting of vertebral artery atherosclerotic disease is safe and effective compared with surgical controls and should be considered first-line therapy for this disease.

Acute stroke intervention by interventional cardiologists

OBJECTIVES

To report the technical success and clinical outcomes of catheter-based therapy (CBT) for acute ischemic stroke in patients ineligible for intravenous thrombolysis.

BACKGROUND

Acute ischemic stroke is common but undertreated. CBT for acute ischemic stroke is a therapeutic option in selected patients who are not candidates for intravenous thrombolysis.

METHODS

Consecutive stroke patients who were ineligible for intravenous thrombolysis and underwent CBT were identified by retrospective chart review. Demographic information, National Institutes of Health Stroke Scale (NIHSS), procedural characteristics, and clinical outcomes during hospitalization and at 90 days follow up were collected. Experienced interventional cardiologists with the consultative support of stroke neurologists were on call for acute strokes.

RESULTS

A total of 33 acute ischemic stroke patients underwent emergency cerebral angiography, with 26 patients undergoing CBT. Successful "culprit" artery recanalization was achieved in 23 (88%) of the 26 patients. In-hospital adverse events occurred in 4 (15%) patients, with intracerebral hemorrhage (ICH) (12%) representing the most common adverse event. The baseline NIHSS for patients who underwent intervention was 16.5 +/- 9.9 (median 16) and improved significantly to 9.9 +/- 8.7 (median 9) (P < 0.001) at hospital discharge. A modified Rankin score of two or less (indicating mild disability) was achieved in half (n = 13) of the CBT treated patients. All cause mortality at 90 days was 8% (2/26).

CONCLUSIONS

In selected patients, CBT provided by qualified interventional cardiologists supported by stroke neurologists, offers a safe and effective option for patients with acute stroke who are not eligible for intravenous thrombolysis.

Carotid artery stent placement is safe in the very elderly (> or =80 years)

BACKGROUND

Carotid artery stent (CAS) placement is an alternative to carotid endarterectomy (CEA) for stroke prevention. Clinical adoption of CAS depends on its safety and efficacy compared to CEA. There are conflicting reports in the literature regarding the safety of CAS in the elderly. To address these safety concerns, we report our single-center 13-year CAS experience in very elderly (> or =80 years of age) patients.

METHODS

Between 1994 and 2007, 816 CAS procedures were performed at the Ochsner Clinic Foundation. Very elderly patients, those > or =80 years of age, accounted for 126 (15%) of all CAS procedures. Independent neurologic examination was performed before and after the CAS procedure.

RESULTS

The average patient age was 82.9 +/- 2.9 years. Almost one-half (44%) were women and 40% were symptomatic from their carotid stenoses. One-third of the elderly patients met anatomic criteria for high surgical risk as their indication for CAS. The procedural success rate was 100% with embolic protection devices used in 50%. The 30-day major adverse coronary or cerebral events (MACCE) rate was 2.7% (n = 3) with all events occurring in the symptomatic patient group [death = 0.9% (n = 1), myocardial infarction = 0%, major (disabling) stroke = 0.9% (n = 1), and minor stroke = 0.9% (n = 1)].

CONCLUSION

Elderly patients, > or =80 years of age, may undergo successful CAS with a very low adverse event rate as determined by an independent neurological examination. We believe that careful case selection and experienced operators were keys to our success.

Diabetes mellitus does not preclude stabilization or improvement of renal function after stent revascularization in patients with kidney insufficiency and renal artery stenosis

OBJECTIVE

To assess the impact of stent revascularization on the renal function of diabetic and nondiabetic patients with renal insufficiency.

BACKGROUND

Renal artery revascularization has been shown to stabilize or improve renal function in patients with significant renal artery stenosis and impaired renal function. However, some studies have suggested negligible or no benefit of renal function in diabetic patients with the same condition.

METHODS

We retrospectively compared data from 50 consecutive patients undergoing renal artery stent placement with renal insufficiency (serum creatinine > or = 1.5-4.0 mg/dl) and global ischemia (bilateral or solitary [single] kidney renal artery stenosis) There were 17 diabetic (DM) and 33 nondiabetic (NDM) patients. The endpoints included the follow-up measurements of renal function, blood pressure, and number of antihypertensive medications.

RESULTS

After stent placement, at a mean follow-up of 42 +/- 18 months (range: 6-62 months), 79% NDM (N = 26), and 76% DM patients (N = 13) (P = NS) had improvement in the slope of the reciprocal of creatinine (1/SCr), indicating a beneficial effect in renal function in many patients.

CONCLUSION

Renal artery stent placement appears to be equally beneficial in preserving renal function in DM and NDM patients with ischemic nephropathy and global renal ischemia.

Endovascular therapy for chronic mesenteric ischemia

OBJECTIVES

We sought to describe the outcomes of a consecutive series of patients with chronic mesenteric ischemia (CMI) who were treated with percutaneous stent revascularization.

BACKGROUND

Historically, the treatment for CMI has been surgical revascularization. However, surgery carries a significant procedural complication rate and mortality.

METHODS

Fifty-nine consecutive patients with CMI underwent stent placement in 79 stenotic (>70%) mesenteric arteries. All patients had clinical follow-up and 90% had anatomical follow-up with angiography (computed tomography or conventional) or ultrasound at > or =6 months after the procedure.

RESULTS

Procedural success was obtained in 96% (76 of 79 arteries) and symptom relief occurred in 88% (50 patients). At a mean follow-up of 38 +/- 15 months (range, 6 to 112 months), 79% of the patients remained alive, and 17% (n = 10) experienced a recurrence of symptoms. Angiography or ultrasound obtained at 14+/- 5 months after the procedure demonstrated a restenosis rate of 29% (n = 20). All patients with recurrent symptoms had angiographic in-stent restenosis and were successfully revascularized percutaneously.

CONCLUSIONS

Percutaneous stent placement for the treatment of CMI can be performed with a high procedural success and a low complication rate. The long-term freedom from symptoms and vascular patency are comparable with surgical results. The inherent lower procedural morbidity and mortality makes the endovascular approach the preferred revascularization technique for these patients.

Elevated Brain Natriuretic Peptide Predicts Blood Pressure Response After Stent Revascularization in Patients With Renal Artery Stenosis

Background— A significant number (20% to 40%) of hypertensive patients with renal artery stenosis will not have blood pressure improvement after successful percutaneous revascularization. Identifying a group of patients with refractory hypertension and renal artery stenosis who are likely to respond to renal stent placement would be beneficial.

Methods and Results— Brain natriuretic peptide (BNP) was measured in 27 patients with refractory hypertension and significant renal artery stenosis before and after successful renal artery stent placement. This neuropeptide was elevated (median, 187 pg/mL; 25th to 75th percentiles, 89 to 306 pg/mL) before stent placement and fell within 24 hours of the successful stent procedure (96 pg/mL; 25th to 75th percentiles, 61 to 182 pg/mL; P =0.002), remaining low (85 pg/mL; 25th to 75th percentiles, 43 to 171 pg/mL) at follow-up. Clinical improvement in hypertension was observed in the patients with a baseline BNP >80 pg/mL (n=22) in 17 patients (77%) compared with 0% of the patients with a baseline BNP ≤80 pg/mL (n=5) ( P =0.001). After correction for glomerular filtration rate, BNP was strongly correlated with improvement in hypertension.

Conclusions— BNP is increased in patients with severe renal artery stenosis and decreases after successful stent revascularization. In addition, an elevated baseline BNP level of >80 pg/mL appears to be a good predictor of a blood pressure response after successful stent revascularization.

Catheter-Based Treatment for Patients With Acute Ischemic Stroke Ineligible for Intravenous Thrombolysis

BACKGROUND AND PURPOSE

We present our single-center experience using catheter-based therapy for acute ischemic stroke patients who were not candidates for intravenous thrombolytic therapy.

METHODS

Neurologic outcomes were assessed in patients with acute ischemic stroke, ineligible for intravenous thrombolysis, treated with an emergent catheter-based therapy.

RESULTS

Nonparametric analysis of neurological outcomes demonstrated a benefit in National Institutes of Health Stroke Scale (NIHSS) at long-term follow-up (P=0.036). Independence in daily activities and improvement in NIHSS of > or =4 points were achieved in 38% and 56% of patients, respectively. Four patients (25%) died, including 2 patients (12.5%) who died from intracranial hemorrhage.

CONCLUSIONS

Catheter-based treatment offers a promising treatment strategy in patients with acute ischemic stroke ineligible for intravenous thrombolysis.

Percutaneous revascularization of the common femoral artery for limb ischemia

We performed percutaneous transluminal intervention in 20 consecutive patients (21 limbs) with common femoral artery (CFA) lesions causing symptomatic limb ischemia. In 12 limbs, concurrent additional percutaneous intervention proximal or distal to the target CFA lesion was performed. Angiographic success was obtained in 100%, with procedural success (angiographic success without a major in-hospital complications) in 90% and clinical success (procedural success and in-hospital improvement by at least one Fontaine functional class) in 81% of the limbs. The in-hospital Fontaine class improved by at least one functional class in 17 of 19 patients (89%), and the overall in-hospital event-free survival was 90% (18 of 20 patients). At follow-up (11.4 +/- 6 months), the overall event-free survival was 90% (18 of 20 patients) and 17 of 19 patients (89%) continue to show improvement by at least one functional (Fontaine) class. Percutaneous intervention of the CFA can be performed with a rate of high technical success and a low complication rate. It provides excellent clinical results at mid-term follow-up and appears to be a reasonable alternative to surgical therapy in patients at high risk for surgery.

Vertebral and intracranial artery angioplasty

Cerebral ischemia is due to either embolic or cerebrovascular occlusive disease, which most commonly occurs as a manifestation of atherosclerosis. Although carotid endarterectomy has been proven more effective than medical therapy in the treatment of cervical carotid disease, there are no effective surgical strategies for the management of vertebral artery or intracranial carotid disease. Management of patients with these conditions is well suited to a multidisciplinary team with the combined skills to provide optimal care. Percutaneous revascularization techniques with balloon angioplasty and stenting can be used to successfully treat occlusive disease of the vertebral and intracranial arteries. Percutaneous revascularization of intracranial and vertebral vessels with angioplasty and stenting is an effective strategy. The outcomes in this difficult to manage cohort of patients appears to be markedly improved over the natural history of this disease with medical therapy alone.

Treatment of coronary stent thrombosis with rheolytic thrombectomy: results from a multicenter experience

The objective of this study was to assess the feasibility, efficacy, and safety of rheolytic thrombectomy (RT) for treatment of coronary stent thrombosis. Stent thrombosis is an infrequent but potentially devastating complication. Conventional treatment with balloon angioplasty and/or thrombolysis has yielded suboptimal results. RT was used to treat 18 patients (mean age, 62 +/- 8 years; 72% male) with in-stent thrombosis (mean time to stent thrombosis, 2.4 +/- 1.8 days). Device success, procedure success, in-hospital and 30-day major cardiovascular events (MACE) were assessed in the hospital and at 30 days. Device success was obtained in 94% and procedure success was achieved in 100% of patients. Following RT, 11 patients underwent balloon angioplasty and 7 patients received additional stents. TIMI 3 coronary flow was obtained in 94.4% and all (100%) patients achieved either TIMI 2 or 3 coronary flow. The angiographic thrombus area decreased from 113.7 +/- 79 to 5.5 +/- 5.7 mm(2) after RT, and to 0.9 +/- 2.1 mm(2) (P < 0.001) after final treatment. Procedural complications were limited to transient no-reflow in five patients. Only one patient evolved a Q-wave MI. At 30 days of follow-up, no patients suffered death, emergent bypass surgery, or stroke. Our data suggest that the adjunctive use of rheolytic thrombectomy offers improved outcomes compared to prior results of intervention after coronary stent thrombosis and should be strongly considered as a treatment option for this complication.

Carotid stents to prevent stroke: a nonsurgical option

Angioplasty and stent placement have become accepted alternatives to surgery in many vascular territories. The most recent application of percutaneous intervention has been to explore its clinical utility and safety for stroke prevention in carotid arteries. Over the past 8 years, from January 1994 until Nov 2002, we performed 449 elective carotid stent procedures in 426 patients and in 481 vessels. Informed consent was obtained from each patient. Success was achieved in 97.3% of the patients treated. After one month of follow-up, 12 (2.8%) patients experienced stroke or death. After an average of 2.8 ± 1.7 years (range 1 month to 8.8 years) of follow-up, restenosis was found in 11 (2.6%) patients and was treated with balloon angioplasty. Our results, in a predominantly high-risk surgery group of patients, suggest that carotid stent placement is a viable treatment alternative to conventional surgery. It is likely that as the technology continues to evolve, the procedural risks of stroke and death will be minimized by embolic protection devices, making carotid stenting an option for low-risk surgical patients.

Induction of mild systemic hypothermia with endovascular cooling during primary percutaneous coronary intervention for acute myocardial infarction

OBJECTIVES

The purpose of this study was to evaluate the safety and feasibility of endovascular cooling during primary percutaneous coronary intervention (PCI) for acute myocardial infarction (AMI).

BACKGROUND

In experimental models of AMI, mild systemic hypothermia has been shown to reduce metabolic demand and limit infarct size.

METHODS

In a multi-center study, 42 patients with AMI (<6 h from symptom onset) were randomized to primary PCI with or without endovascular cooling (target core temperature 33 degrees C). Cooling was maintained for 3 h after reperfusion. Skin warming, oral buspirone, and intravenous meperidine were used to reduce the shivering threshold. The primary end point was major adverse cardiac events at 30 days. Infarct size at 30 days was measured using (99m)Tc-sestamibi SPECT imaging.

RESULTS

Endovascular cooling was performed successfully in 20 patients (95%). All achieved a core temperature below 34 degrees C (mean target temperature 33.2 +/- 0.9 degrees C). The mean temperature at reperfusion was 34.7 +/- 0.9 degrees C. Cooling was well tolerated, with no hemodynamic instability or increase in arrhythmia. Nine patients experienced mild episodic shivering. Major adverse cardiac events occurred in 0% vs. 10% (p = NS) of treated versus control patients. The median infarct size was non-significantly smaller in patients who received cooling compared with the control group (2% vs. 8% of the left ventricle, p = 0.80).

CONCLUSIONS

Endovascular cooling can be performed safely as an adjunct to primary PCI for AMI. Further clinical trials are required to determine whether induction of mild systemic hypothermia with endovascular cooling will limit infarct size in patients undergoing reperfusion therapy.

Endovascular Treatment for Vertebrobasilar Insufficiency

Endovascular management of supra-aortic atherosclerotic vascular disease is becoming relatively common in the innominate, subclavian, and carotid arteries. However, revascularization of vertebral artery disease is an infrequently used treatment option due to several reasons: 1) stroke etiology and prevention is generally considered with respect to carotid disease as posterior circulation ischemia is poorly defined; 2) the limited success and excessive morbidity have made surgery an unattractive option for vertebral artery revascularization; 3) routine screening for posterior circulation disease as an etiology for stroke is rarely performed; and 4) endovascular treatment of vertebrobasilar insufficiency is not routinely performed in peripheral interventional programs. Randomized data comparing medical therapy, endovascular treatment, or surgical treatment do not exist. Due to infrequent identification of vertebral artery disease as the etiology of posterior circulation symptomatology, randomized comparisons will be difficult to obtain. Balloon angioplasty alone, provisional stenting, or primary stent placement for the treatment of vertebral artery stenosis is associated with low restenosis rates and high success rates. The available literature demonstrates angioplasty with stent placement of posterior circulation, symptomatic, vertebrobasilar atherosclerotic disease is a safe and effective approach that avoids the morbidity associated with major surgery. We believe primary stent placement is the treatment of choice for vertebral artery revascularization due to the high technical success rate, low incidence of morbidity and mortality, and long-term durability.