Rebecca Torguson

Late thrombosis in drug-eluting coronary stents after discontinuation of antiplatelet therapy

Although the safety profiles of coronary stents eluting sirolimus or paclitaxel do not seem to differ from those of bare metal stents in the short-to-medium term, concern has arisen about the potential for late stent thromboses related to delayed endothelialisation of the stent struts. We report four cases of angiographically-confirmed stent thrombosis that occurred late after elective implantation of polymer-based paxlitaxel-eluting (343 and 442 days) or sirolimus-eluting (335 and 375 days) stents, and resulted in myocardial infarction. All cases arose soon after antiplatelet therapy was interrupted. If confirmed in systematic long-term follow-up studies, our findings have potentially serious clinical implications.

Correlates and Long-Term Outcomes of Angiographically Proven Stent Thrombosis With Sirolimus- and Paclitaxel-Eluting Stents

Background— Stent thrombosis (ST) is a serious complication of drug-eluting stent (DES) implantation regardless of the timing (acute, subacute, or late). The correlates of ST with DES are not yet completely elucidated. Methods and Results— From a total cohort of 2974 consecutive patients treated with DES since April 2003, we identified 38 patients who presented with angiographic evidence of ST (1.27%). The ST occurred acutely in 5 patients, subacutely (≤30 days) in 25 patients, and late (>30 days) in 8 patients. The clinical, angiographic, and procedural variables of these patients were compared with the remaining 2936 consecutive patients who underwent DES implantation and did not experience ST during a follow-up of 12 months. Logistic regression analysis was conducted to determine the correlates of ST. Compared with patients without ST, patients with ST had a higher frequency of diabetes, acute postprocedural renal failure, and chronic renal failure. There were more bifurcation lesions, type C lesions, and a trend for smaller-diameter stents. Discontinuation of clopidogrel was higher in these patients (36.8% versus 10.7%; P<0.0001). The mean duration to ST from the stent implantation was 8.9±8.5 days in subacute and 152.7±100.4 days in late thrombosis cases. Mortality was significantly higher in patients with ST compared with those without ST at 6 months (31% versus 3%; P<0.001). Multivariate analysis detected cessation of clopidogrel therapy, renal failure, bifurcation lesions, and in-stent restenosis as significant correlates of ST (P<0.05). Conclusions— ST continues to be a serious complication of contemporary DES use. Careful management is warranted in patients with renal failure and in those undergoing treatment for in-stent restenosis and bifurcations. Special focus on clopidogrel compliance may minimize the incidence of ST after DES implantation.

Complications and Outcome of Balloon Aortic Valvuloplasty in High-Risk or Inoperable Patients

OBJECTIVES This study aimed to determine the success, complications, and survival of patients after balloon aortic valvuloplasty (BAV). BACKGROUND The introduction of transcatheter aortic valve implantation (TAVI) BAV has led to a revival in the treatment of patients with severe aortic stenosis. METHODS A cohort of 262 patients with severe aortic stenosis underwent 301 BAV procedures. Of these, 39 (14.8%) patients had ≥2 BAV procedures. Clinical, hemodynamic, and follow-up mortality data were collected. RESULTS The cohort mean age was 81.7 ± 9.8 years, and the mean Society of Thoracic Surgeons and logistic EuroSCORE (European System for Cardiac Operative Risk Evaluation) was 13.3 ± 6.7 and 45.6 ± 21.6, respectively. BAV was performed as a bridge to TAVI or to surgical aortic valve replacement in 28 patients (10.6%) and for symptom relief in 234 (89.4%). The mean aortic valve area (AVA) increased from 0.58 ± 0.3 cm(2) to 0.96 ± 0.3 cm(2) (p < 0.001). Of these, 111 (45.0%) had final AVA >1 cm(2), and in 195 patients (79%), AVA increased by >40%. De novo BAV resulted in a higher mean increase in AVA 0.41 ± 0.24 cm(2) versus 0.28 ± 0.24 cm(2) in redo BAV (p = 0.003). Serious adverse events occurred in 47 patients (15.6%), intraprocedural death in 5 (1.6%), stroke in 6 (1.99%), coronary occlusion in 2 (0.66%), severe aortic regurgitation in 4 (1.3%), resuscitation/cardioversion in 5 (1.6%), tamponade in 1 (0.33%), and permanent pacemaker in 3 (0.99%). A vascular complication occurred in 21 patients (6.9%); 34 (11.3%) had a post-procedure rise in creatinine >50%; and 3 (0.99%) required hemodialysis. During median follow-up of 181 days, the mortality rate was 50% (n = 131). The mortality rate in the group with final AVA >1 cm(2) was significantly lower than in the group with final AVA of <1 cm(2) (36.4% vs. 57.9%, p < 0.001). Final AVA was associated with lower mortality (hazard ratio: 0.46, p = 0.03). BAV as a bridge to TAVI or surgical aortic valve replacement had a better outcome compared with BAV alone: mortality rate 7 (25%) versus 124 (52.9%), respectively (p < 0.0001). CONCLUSIONS Long-term survival is poor after BAV alone. BAV as a bridge to percutaneous or surgical aortic valve replacement is feasible, safe, and associated with better outcome than BAV alone.

A First-in-Man, Randomized, Placebo-Controlled Study to Evaluate the Safety and Feasibility of Autologous Delipidated High-Density Lipoprotein Plasma Infusions in Patients With Acute Coronary Syndrome

OBJECTIVES This study aimed to determine whether serial autologous infusions of selective high-density lipoprotein (HDL) delipidated plasma are feasible and well tolerated in patients with acute coronary syndrome (ACS). BACKGROUND Low HDL is associated with increased risk of cardiovascular disease. Plasma selective delipidation converts alphaHDL to prebeta-like HDL, the most effective form of HDL for lipid removal from arterial plaques. METHODS ACS patients undergoing cardiac catheterization with >or=1 nonobstructive native coronary artery atheroma were randomized to either 7 weekly HDL selective delipidated or control plasma apheresis/reinfusions. Patients underwent intravascular ultrasound (IVUS) evaluation of the target vessel during the catheterization for ACS and up to 14 days following the final apheresis/reinfusion session. 2-D gel electrophoresis of delipidated plasmas established successful conversion of alphaHDL to prebeta-like HDL. The trial was complete with 28 patients randomized. RESULTS All reinfusion sessions were tolerated well by all patients. The levels of prebeta-like HDL and alphaHDL in the delipidated plasma converted from 5.6% to 79.1% and 92.8% to 20.9%, respectively. The IVUS data demonstrated a numeric trend toward regression in the total atheroma volume of -12.18 +/- 36.75 mm(3) in the delipidated group versus an increase of total atheroma volume of 2.80 +/- 21.25 mm(3) in the control group (p = 0.268). CONCLUSIONS In ACS patients, serial autologous infusions of selective HDL delipidated plasma are clinically feasible and well tolerated. This therapy may offer a novel adjunct treatment for patients presenting with ACS. Further study will be needed to determine its ability to reduce clinical cardiovascular events.

Outcomes of Coronary Artery Bypass Grafting Versus Percutaneous Coronary Intervention With Drug-Eluting Stents for Patients With Multivessel Coronary Artery Disease

Background— Advances in coronary artery bypass grafting (CABG) surgery and percutaneous coronary intervention (PCI) with drug-eluting stents have dramatically improved results of these procedures. The optimal treatment for patients with multivessel coronary artery disease is uncertain given the lack of prospective, randomized data reflecting current practice. This study represents a “real-world” evaluation of current technology in the treatment of multivessel coronary artery disease. Methods and Results— A total of 1680 patients undergoing revascularization for multivessel coronary artery disease were identified. Of these, 1080 patients were treated for 2-vessel disease (196 CABG and 884 PCI) and 600 for 3-vessel disease (505 CABG and 95 PCI). One-year mortality, cerebrovascular events, Q-wave myocardial infarction, target vessel failure, and composite major adverse cardiovascular and cerebrovascular events were compared between the CABG and PCI cohorts. Outcomes were adjusted for baseline covariates and reported as hazard ratios. The unadjusted major adverse cardiovascular and cerebrovascular event rate was reduced with CABG for patients with 2-vessel disease (9.7% CABG versus 21.2% PCI; P<0.001) and 3-vessel disease (10.8% CABG versus 28.4% PCI; P<0.001). Adjusted outcomes showed increased major adverse cardiovascular and cerebrovascular event with PCI for patients with 2-vessel (hazard ratio 2.29; 95% CI 1.39 to 3.76; P=0.01) and 3-vessel disease (hazard ratio 2.90; 95% CI 1.76 to 4.78; P<0.001). Adjusted outcomes for the nondiabetic subpopulation demonstrated equivalent major adverse cardiovascular and cerebrovascular event with PCI for 2-vessel (hazard ratio 1.77; 95% CI 0.96 to 3.25; P=0.07) and 3-vessel disease (hazard ratio 1.70; 95% CI 0.77 to 3.61; P=0.19). Conclusions— Compared with PCI with drug-eluting stents, CABG resulted in improved major adverse cardiovascular and cerebrovascular event in patients with 2- and 3-vessel coronary artery disease, primarily in those with underlying diabetes. Coronary artery bypass surgery may be the preferred revascularization strategy in diabetic patients with multivessel coronary artery disease.

The impact of proprotein convertase subtilisin-kexin type 9 serine protease inhibitors on lipid levels and outcomes in patients with primary hypercholesterolaemia: a network meta-analysis.

AIMS We performed a network meta-analysis of randomized controlled trials (RCTs) in patients with primary hypercholesterolaemia to compare the impact of proprotein convertase subtilisin-kexin type 9 serine protease (PCSK9) inhibitors with placebo and ezetimibe on lipid levels and outcomes. METHODS AND RESULTS MEDLINE/PubMed, Cochrane CENTRAL, and ClinicalTrials.gov were searched for RCTs assessing PCSK9 inhibitors vs. other therapies in patients with primary hypercholesterolaemia. Network meta-analysis with both a frequentist approach and a Bayesian framework was performed to directly and indirectly compare PCSK9 inhibition on lipid levels with ezetimibe and placebo. Odds ratios with 95% confidence intervals (OR [95% CIs]) were generated with random-effects models to compare outcomes. Our meta-analysis included 17 RCTs with 13 083 patients that were randomized to PCSK9 inhibitors (n = 8250), placebo (n = 3957), ezetimibe (n = 846), or PCSK9 inhibitors and ezetimibe (n = 30). The mean age was 59 ± 10, 52% were male, 34% had coronary artery disease, 51% had hypertension, 19% had diabetes mellitus, baseline LDL of 122 ± 36 mg/dL, total cholesterol of 199 ± 39 mg/dL, and HDL of 51 ± 14 mg/dL. inhibitors significantly reduced LDL cholesterol by 57% relative to placebo (P < 0.001) and 36.1% relative to ezetimibe (P < 0.001). Proprotein convertase subtilisin-kexin type 9 serine protease inhibitors reduced the incidence of all-cause mortality [OR 0.43 (95% CI 0.22-0.82), P = 0.01] but was associated with an increased incidence of neurocognitive adverse events [OR 2.34 (95% CI 1.11-4.93), I(2) = 4%, P = 0.02] when compared with placebo. CONCLUSION Proprotein convertase subtilisin-kexin type 9 serine protease inhibition significantly improved lipid profiles and reduced the incidence of all-cause mortality compared with placebo but had a higher rate of neurocognitive adverse events. Thus, PCSK9 inhibitor therapy may serve as an alternative for patients with statin intolerance and for those who do not respond to other lipid reduction therapy.

FIRST: Fractional Flow Reserve and Intravascular Ultrasound Relationship Study.

OBJECTIVES FIRST (Fractional Flow Reserve and Intravascular Ultrasound Relationship Study) aimed to determine the optimal minimum lumen area (MLA) by intravascular ultrasound (IVUS) that correlates with fractional flow reserve (FFR) and to assess the correlation between virtual histology IVUS and FFR for intermediate coronary lesions. BACKGROUND FFR is considered the gold standard for assessing intermediate coronary lesions. Measurements of ≤0.8 are considered clinically significant and indicative of physiological ischemia. METHODS FIRST is a multicenter, prospective, international registry of patients with intermediate coronary lesions, defined as 40% to 80% stenosis by angiography. In total, 350 patients (367 lesions) were enrolled at 10 U.S. and European sites. Patients were followed through hospital discharge. RESULTS Overall, an MLA <3.07 mm(2) (64.0% sensitivity, 64.9% specificity, area under curve [AUC] = 0.65) was the best threshold value for identifying FFR <0.8. The accuracy improved when reference vessel-specific analyses were performed. An MLA <2.4 mm(2) (AUC = 0.66) was best for reference vessel diameters <3.0 mm, an MLA <2.7 mm(2) (AUC = 0.71) for reference vessel diameters of 3.0 to 3.5 mm, and an MLA <3.6 mm(2) (AUC = 0.68) for reference vessel diameters >3.5 mm. FFR correlated with plaque burden (r = -0.220, p < 0.001) but not with other plaque morphology. CONCLUSIONS Anatomic measurements by IVUS show a moderate correlation with the FFR values. The optimal cutoff for an MLA to FFR <0.8 is vessel dependent. Plaque morphology characteristics do not correlate with FFR. The utility of IVUS MLA as an alternative to FFR to guide intervention in intermediate lesions may be limited in accuracy and should be tested clinically. (Fractional Flow Reserve and Intravascular Ultrasound Relationship Study [FIRST]; NCT01153555).

Intracoronary radiation therapy improves the clinical and angiographic outcomes of diffuse in-stent restenotic lesions: Results of the Washington Radiation for In-Stent Restenosis Trial for long lesions (Long WRIST) studies

Background—The Washington Radiation for In-Stent Restenosis Trial for long lesions (Long WRIST) was designed to determine the safety and efficacy of vascular brachytherapy for the treatment of diffuse in-stent restenosis. Methods and Results—A total of 120 patients with diffuse in-stent restenosis in native coronary arteries (lesion length, 36 to 80 mm) were randomized for either radiation with 192Ir with 15 Gy at 2 mm from the source axis or placebo. After enrollment, 120 additional patients with the same inclusion criteria were treated with 192Ir with 18 Gy and included in the Long WRIST High Dose registry. Antiplatelet therapy was initially prescribed for 1 month and was extended to 6 months in the last 60 patients of the Long WRIST High Dose registry. At 6 months, the binary angiographic restenosis rate was 73%, 45%, and 38% in the placebo, 15 Gy, and 18 Gy radiated groups, respectively (P <0.05). At 1 year, the primary clinical end point of major cardiac events was 63% in the placebo group and 42% in the radiated group with 15 Gy (P <0.05). The major cardiac event rate was further reduced with 18 Gy (22%;P <0.05 versus 15 Gy). Late thrombosis was 12%, 15%, and 9% in the placebo group, 15 Gy group with 1 month of antiplatelet therapy, and 18 Gy group with 6 months of antiplatelet therapy, respectively. Conclusions—Vascular brachytherapy with 192Ir is safe and reduces the rate of recurrent restenosis in diffuse in-stent restenosis. The efficacy of vascular brachytherapy on angiographic and clinical outcomes is enhanced with a radiation dose of 18 Gy and prolonged antiplatelet therapy.

Clinical profile, prognostic implication, and response to treatment of pulmonary hypertension in patients with severe aortic stenosis.

The incidence, correlates, and prognostic implications of pulmonary hypertension (PH) are unclear in patients with severe aortic stenosis (AS). We studied 509 patients with severe AS evaluated for transcatheter aortic valve implantation (TAVI). Patients were divided into groups based on pulmonary artery systolic pressure (PASP): group I, 161 (31.6%) with PASP <40 mm Hg; group II, 175 (34.3%) with PASP 40 to 59 mm Hg; and group III, 173 (33.9%) with PASP ≥ 60 mm Hg. Group III patients were more symptomatic and had higher creatinine levels and higher left ventricular end-diastolic pressure. Transpulmonary gradient was >12 mm Hg in 17 patients (10.5%), 31 patients (17.7%), and 80 patients (46.2%) in groups I through III, respectively. In a median follow-up of 202 days (73 to 446) mortality rates were 35 (21.7%), 69 (39.3%), and 85 (49.1%) in groups I through III, respectively (p <0.001). Immediately after TAVI, in patients with PASP >40 mm Hg there was significant decrease in PASP (63.1 ± 16.2 to 48.8 ± 12.4 mm Hg, p <0.0001), which remained at 1 year (50.1 ± 13.1 mm Hg, p = 0.04). After surgical aortic valve replacement there was a significant immediate decrease in PASP (66.1 ± 16.3 to 44.7 ± 14.2 mm Hg, p <0.0001), which persisted at 3 to 12 months (44.8 ± 20.1 mm Hg, p <0.001). In patients who underwent balloon aortic valvuloplasty, PASP decreased immediately after the procedure (63.2 ± 14.8 to 51.8 ± 17.1 mm Hg, p <0.0001), yet at 3 to 12 months pressure returned to baseline levels (57.4 ± 17.0 mm Hg, p = 0.29). In conclusion, patients with severe AS have a high prevalence of PH, and in patients with severe AS increased PASP is associated with increased mortality. Surgical aortic valve replacement and TAVI are effective treatments for these patients and result in a significant PASP decrease.

Scaffold Thrombosis After Percutaneous Coronary Intervention With ABSORB Bioresorbable Vascular Scaffold: A Systematic Review and Meta-Analysis

OBJECTIVES The aim of this study was to determine the risk of scaffold thrombosis (ST) after percutaneous coronary intervention (PCI) with placement of an ABSORB bioresorbable vascular scaffold (BVS) (Abbott Vascular, Santa Clara, California) by conducting a systematic review and meta-analysis. BACKGROUND PCI with BVS placement holds great potential, but concern has recently been raised regarding the risk of ST. METHODS MEDLINE/PubMed, Cochrane CENTRAL, and meeting abstracts were searched for all studies that included outcomes data for patients after PCI with BVS placement. For studies comparing BVSs with drug-eluting stents (DES), pooled estimates of outcomes, presented as odds ratios (ORs) with 95% confidence intervals (CIs), were generated with random-effects models. RESULTS Our analysis included 10,510 patients (8,351 with a BVS and 2,159 with DES) with a follow-up of 6.4 ± 5.1 months and 60 ± 11 years of age; 78% were male, 36% had stable angina, and 59% had acute coronary syndrome (ACS). Among patients with a BVS, cardiovascular death occurred in 0.6%, myocardial infarction (MI) in 2.1%, target lesion revascularization in 2.0%, and definite/probable ST in 1.2% of patients. Of BVS patients, 0.27% had acute ST and 0.57% had subacute ST. Meta-analysis demonstrated that patients who received a BVS were at a higher risk of MI (OR: 2.06, 95% CI: 1.31 to 3.22, p = 0.002) and definite/probable ST (OR: 2.06, 95% CI: 1.07 to 3.98, p = 0.03) compared with patients who received DES, whereas there was a trend toward decreased all-cause mortality with a BVS (OR: 0.40, 95% CI: 0.15 to 1.06, p = 0.06). CONCLUSIONS Patients undergoing PCI with a BVS had increased definite/probable ST and MI during follow-up compared with DES. Further studies with long-term follow-up are needed to assess the risk of ST with a BVS.