Azeem Latib

Bifurcation Disease: What Do We Know, What Should We Do?

The percutaneous treatment of coronary bifurcations has moved past an important milestone in that the 1- versus 2-stent debate appears to have been resolved. The provisional approach of implanting one stent on the main branch should be the default approach in most bifurcations lesions. Selection of the most appropriate strategy for an individual bifurcation is important. Some bifurcations require 1 stent, whereas others require the stenting of both branches. Irrespective of whether a 1- or 2-stent strategy is chosen, the results after bifurcation percutaneous coronary intervention (PCI) have dramatically improved. Dedicated bifurcation stents are an exciting new technology that may further simplify the management of bifurcation PCI and change some of these concepts.

Predictors of moderate-to-severe paravalvular aortic regurgitation immediately after corevalve implantation and the impact of postdilatation†

Objective: To investigate the predictors of moderate‐to‐severe aortic regurgitation (AR≥2+) after CoreValve implantation and evaluate the feasibility and safety of postdilatation in reducing the degree of AR. Background: Although transcatheter aortic valve implantation is an alternative treatment for high surgical risk patients with severe aortic stenosis, post‐implantation paravalvular AR remains a complication. Methods: From July 2008 to July 2010, we enrolled 79 consecutive patients with severe aortic stenosis who underwent CoreValve implantation. Results: On univariable analysis, the predictors of AR≥2+ immediately after CoreValve implantation were: larger annulus size, low implantation, prosthesis mismatch, chronic renal insufficiency, a history of heart failure, and peripheral vascular disease. On multivariable analysis, the independent predictors of AR≥2+ were: larger annulus diameter (OR 1.78, 95%CI 1.25–2.55; P = 0.002), low implantation (OR 3.67, 95%CI 1.01–13.35, P = 0.05), and peripheral vascular disease (OR 3.54, 95%CI 1.19–10.56, P = 0.02). Post‐CoreValve implantation, AR ≥ 2 was seen in 40.5% (32/79). Twenty‐one patients underwent postdilatation with improvement in AR grade in the majority (17/21). Of the four patients who did not respond to postdilatation, two underwent valve‐in‐valve implantation. In one patient, the valve was pulled more proximally by the snare technique. The remaining 10 patients were treated conservatively. Conclusion: The appropriate strategy for treating patients with AR≥2+ depends on the causes and severity of AR post‐TAVI. This study suggests that we should carefully select the size of CoreValve prosthesis to prevent prosthesis mismatch, especially when implanted in larger annulus sizes. For valves implanted in the appropriate position, postdilatation appears effective in reducing the degree of AR.

Clinical features, survival experience, and profile of plakophylin-2 gene mutations in participants of the Arrhythmogenic Right Ventricular Cardiomyopathy Registry of South Africa

Little is known about arrhythmogenic right ventricular cardiomyopathy (ARVC) in Africa. The objective of this study was to delineate the clinical characteristics, survival, and genetics of ARVC in South Africa. Information on clinical presentation, electrocardiographic and cardiac imaging findings, histology, and outcome of cases with suspected ARVC was collected using the standardised form of the ARVC Registry of South Africa. Genomic DNA was screened for mutations in plakophylin-2 (PKP2) gene. Survival and its predictors were analyzed using the Kaplan-Meier and Cox proportional hazards regression methods, respectively. Fifty unrelated cases who met the diagnostic criteria for ARVC were enrolled between January 2004 and April 2009. Clinical presentation was similar to that reported in other studies. Annual mortality rate was 2.82%, five-year cumulative mortality rate 10%, and mean age at death 36.9 +/- 14.7 years. Overall survival was similar to the general South African population (P = 0.25). Independent risk factors for death were syncope (Hazard Ratio [HR] 10.73, 95% Confidence Interval [CI] 1.88-61.18, P = 0.008) and sustained ventricular tachycardia (HR = 22.97, 95%CI 2.33-226.18, P = 0.007). Seven PKP2 gene mutations were found in 9/36 (25%) unrelated participants, five being novel. The novel C1162T mutation occurred in four white South Africans sharing a common haplotype, suggesting a founder effect. Compound heterozygotes exhibited a severe phenotype signifying an allele dose effect. ARVC is associated with early mortality that is no different to the general South Africa population whose lifespan is shortened by HIV/AIDS. PKP2 gene mutations are common, have an allele dose effect, and a novel founder effect in white South Africans.

Clinical Outcomes After Unrestricted Implantation of Everolimus-Eluting Stents

OBJECTIVESnThe aim of this study was to evaluate the efficacy and safety of unrestricted everolimus-eluting stent (EES) implantation in a contemporary cohort of real-world patients.nnnBACKGROUNDnThe randomized SPIRIT (A Clinical Evaluation of the XIENCE V Everolimus Eluting Coronary Stent System in the Treatment of Patients With de Novo Native Coronary Artery Lesions) trials have evaluated the performance of EES, resulting in their approval by the Food and Drug Administration, but data regarding unselected usage, including off-label indications are lacking.nnnMETHODSnConsecutive patients treated with EES (either PROMUS, Boston Scientific Corp., Natick, Massachusetts, or XIENCE-V, Abbott Vascular Devices, Santa Clara, California) between October 2006 and February 2008 were analyzed. End points were cardiac death, myocardial infarction (MI), ischemic-driven target lesion revascularization (TLR), stent thrombosis (ST), and major adverse cardiac events (MACE) (a composite of cardiac death, MI, TLR) during follow-up.nnnRESULTSnWe identified 345 patients (573 lesions) treated with EES. The majority of patients (71.9%) were treated for > or =1 off-label or untested indication. Clinical follow-up was completed in 99%. At a median follow-up of 378 days (interquartile range 334 to 473), MACE occurred in 36 (10.6%) patients, TLR in 27 (7.9%), MI in 7 (2.1%), and cardiac death in 7 (2.1%). Definite and probable ST was observed in 3 (0.9%) cases. Off-label EES implantation was not associated with a statistically significant increased risk of MACE (12.2% vs. 6.3%, p = 0.17), TLR (9.3% vs. 4.2%, p = 0.18), or ST (0.8% vs. 1.1%, p = 1.0). On multivariable analysis, previous bypass surgery (p = 0.002) and diabetes (p = 0.03) were associated with MACE.nnnCONCLUSIONSnIn unrestricted daily practice, EES were implanted predominantly for off-label indications and associated with a relative low rate of MACE and TLR.

Incidence of Bleeding and Compliance on Prolonged Dual Antiplatelet Therapy (Aspirin Thienopyridine) Following Drug-Eluting Stent Implantation

Prolonged periods of dual antiplatelet therapy (DAT), i.e., aspirin plus a thienopyridine, are currently recommended to prevent late drug-eluting stent (DES) thrombosis. The aim of our study was to determine the risk and predictors of bleeding and compliance associated with such prolongation of DAT. In this observational study we examined 2,355 consecutive patients undergoing successful DES implantation at 4 hospitals in Italy from June 2002 to December 2004. Bleeding events occurring on DAT and warfarin or in the first 30 days after stent implantation were excluded. Median duration of DAT was 209 days (interquartile range 178 to 444) and only 158 patients (6.7%) prematurely discontinued DAT. The overall bleeding rate was 1.9% (45), with major bleeding in 19 (0.8%) and minor bleeding in 26 (1.1%). Independent predictors of bleeding were DAT (hazard ratio 19.8, 95% confidence interval [CI] 3.69 to 106.34, p <0.001) and age >65 years (hazard ratio 2.15, 95% CI 1.16 to 4.00, p = 0.02). In patients on DAT, the incidence rate (30 days to 18 months) of any bleeding event was 2.57 per 100 person-years (95% CI 1.85 to 3.48) and major bleeding was 1.10 per 100 person-years (95% CI 0.65 to 1.74). In conclusion, DAT after DES implantation is well tolerated and associated with a very low risk of major bleeding.

Comparison of the Long-Term Safety and Efficacy of Drug-Eluting and Bare-Metal Stent Implantation in Saphenous Vein Grafts

Background—Concerns about the long-term safety of drug-eluting stents (DES) in saphenous vein grafts has become an area of controversy and uncertainty. Methods and Results—In this retrospective registry, we compared the outcomes in 127 patients (143 lesions) treated with DES from April 2002 to June 2006 (DES group) with 131 patients (160 lesions) treated with bare-metal stents in the preceding 36 months (bare-metal stent group). End points analyzed were cumulative death, myocardial infarction, and target vessel revascularization at 2 years after stent implantation. The DES group was significantly (P<0.05) more complex with a greater frequency of diabetes (33.1% versus 15.3%), older grafts (11.6±5.3 years versus 9.6±5.2 years), restenotic lesions (23.8% versus 4.4%), total occlusions (7.7% versus 1.2%), and smaller grafts (3.16±0.66 mm versus 3.44±0.76 mm) treated with longer stents (34.1±25.1 mm versus 22.7±11.6 mm). At 2 years, there was no statistical difference in death (8.7% versus 7.8%), myocardial infarction (6.3% versus 9.4%), or target vessel revascularization (19.7% versus 24.2%) between DES and bare-metal stents, respectively. A propensity analysis to adjust for baseline differences suggested that there was no observed association between DES and increased mortality (hazard ratio, 0.72; 95% CI, 0.21 to 2.44; P=0.60) but possibly an association with a reduction in target vessel revascularization (hazard ratio, 0.31; 95% CI, 0.14 to 0.66; P=0.002). Conclusions—Despite being implanted in patients and lesions more complex than the bare-metal stent group, there was no observed association between DES implantation in saphenous vein grafts and an increase in late mortality. DES may maintain their efficacy in reducing revascularization rates in diseased saphenous vein grafts over a 2-year follow-up period.

Current and future drug-eluting coronary stent technology.

Despite the impressive benefits obtained following the introduction of the drug-eluting stent, safety concerns have been raised over their long-term safety with particular regard to stent thrombosis. Various mechanisms such as delayed endothelialization, local hypersensitivity and endothelial dysfunction owing to the durable polymer coating and/or the drug itself have been suggested as possible causes of this phenomenon. Therefore, to address these concerns, a newer-generation of drug-eluting stents has been developed and they are currently undergoing preclinical and clinical evaluation in order to increase both the safety and biocompatibility by optimizing the three major components of drug-eluting stents: the stent platform, the polymer and the drug. This article critically reviews the key clinical trials and the current status of these new coronary devices as well as preventing future perspectives for their continued development.

Aspirin intolerance and the need for dual antiplatelet therapy after stent implantation: A proposed alternative regimen

BACKGROUNDnDual antiplatelet therapy (DAT, i.e. aspirin+thienopyridine) has been shown to reduce the risk of stent thrombosis (ST) and myocardial infarction (MI) after coronary stent implantation. Data regarding alternative antiplatelet therapy in patients with allergy or intolerance to aspirin are lacking.nnnMETHODSnThis study is a retrospective analysis of consecutive patients with adverse reactions to aspirin who received an alternative combination of DAT (indobufen, trapidil, or triflusal in association with a thienopyridine) after elective implantation of either drug-eluting (DES) or bare-metal stents (BMS). Endpoints analyzed were cardiac death, MI, ST and bleeding.nnnRESULTSnA total of 127 patients undergoing stenting of 267 lesions (DES 84%, BMS 16%), were identified between June99 and November08. Reasons for not taking aspirin included gastrointestinal intolerance (53.5%), allergy (39.4%), non-gastrointestinal bleeding (5.5%) and others (1.6%). Aspirin was substituted with indobufen (64.6%), trapidil (26.8%), triflusal (6.3%), or a combination of indobufen+trapidil (2.4%). Median duration of DAT was 369 days [IQR 273-1053] after DES and 46.5 days [IQR 30-699] after BMS implantation. Only 3.1% of patients prematurely discontinued DAT. During a median follow-up of 1161 days [IQR 781-1538], rates of cardiac death and MI were 3.1% and minor bleeding occurred in 1.5%. There was 1 very late definite ST occurring 2 days after DAT discontinuation and no probable ST.nnnCONCLUSIONSnIn this cohort of patients with aspirin intolerance undergoing coronary stent implantation, the combination of a thienopyridine with indobufen, trapidil, or triflusal was associated with a low rate of cardiac death, ST and MI.

A novel device for true lumen re-entry after subintimal recanalization of superficial femoral arteries: first-in-man experience and technical description.

Subintimal angioplasty (SAP) is frequently performed for the treatment of critical limb ischemia (CLI) and has been recognized as an effective technique for these patients. Nevertheless, this approach is limited by the lack of controlled re-entry into the true lumen of the target vessel. We describe a novel device for true lumen re-entry after subintimal recanalization of superficial femoral arteries (SFA). We report our experience with six patients treated between April 2009 and January 2010 with a novel system designed to facilitate true lumen re-entry. The device was advanced by ipsilateral antegrade approach through a 6-French sheath. Successful reaccess into the true lumen was obtained in five of six patients without complications. The patient in whom the reaccess to the true lumen was not possible underwent successful bypass surgery. At 30xa0days follow-up, the SFA was patent in all patients according to echo-Doppler examination. Our preliminary experience indicates that this novel re-entry device increases the success rate of percutaneous revascularization of chronically occluded SFA.

Clinical Outcomes following Protected Carotid Artery Stenting in Symptomatic and Asymptomatic Patients

Purpose: To evaluate clinical outcomes in patients undergoing carotid artery stenting (CAS) with routine use of a cerebral embolic protection device (EPD). Methods: A retrospective cohort analysis was conducted of 490 consecutive patients (365 men; mean age 70.7±8.5 years) who underwent CAS with EPD between January 1999 and December 2007 at 2 institutions with large referral practices. There were 163 symptomatic patients with stenosis ≥50% and 327 asymptomatic patients with ≥80% diameter stenosis treated in 536 CAS procedures. Nearly a quarter (116, 23.7%) of the cohort had diabetes. High-risk surgical features were present in 141 (28.8%): 73 (14.9%) aged ≥80 years, 25 (5.1%) with significant heart disease, 23 (4.6%) with postsurgical restenosis, and 16 (3.2%) with contralateral carotid occlusion. An EPD was successfully placed in 512 (95.5%) patients. Results: The incidence of any stroke within 30 days was 3.3% (16/490), of which the majority (13, 2.6%) were ipsilateral [5 (1.0%) major and 8 (1.6%) minor]. The incidence of major adverse events (MAE), i.e., any stroke, death or myocardial infarction, within 30 days was 3.7% (18/490); the incidence of 30-day any stroke/death was 3.7% (18/490), while the cumulative incidence of any stroke/death at 1 year was 6.1% (30/490). In symptomatic patients, the 30-day MAE rate was 6.7% (11/163) versus 2.1% (7/237) in the asymptomatic group (p=0.02). A subgroup analysis based on surgical risk showed that the 30-day MAE rate was similar between high-risk and non-high-risk patients [4.9% (7/144) versus 3.2% (11/346); p=0.5]. Conclusion: In this large real-world cohort, CAS with routine use of EPDs was technically feasible, clinically safe, and associated with a low rate of periprocedural and 1-year events; results were similar irrespective of surgical risk.