Update on coronary artery bioresorbable vascular scaffolds in percutaneous coronary revascularization.

Coronary angioplasty was first introduced in 1977. From plain old balloon angioplasty to the introduction of bare metal stents in 1986 and dual antiplatelet therapy in 1992 to much more later on. Due to the unacceptable rate of stent restenosis, drug eluting stents (DES) were introduced in 2000. The first generation showed an increase in late stent thrombosis which led to the introduction of the second generation DES with biocompatible or biodegradable polymers and thinner platforms. However very late stent thrombosis and late restenosis might still pose problems in the latter. Furthermore, there has been major debate regarding the impact of long-term vessel caging on normal vasomotricity and long-term positive remodeling. To resolve these issues, the bioresorbable vascular scaffolds (BVS) were launched into the real world in 2011, showing promising initial results. Multiple randomized trials, meta-analyses, and registries were performed, mainly with the Absorb Bioresorbable Vascular Scaffold System (Abbott Vascular, Chicago, IL, USA). This new technology is hindered by certain features, such as the BVS radial strength, its strut thickness, and the inflammatory process related to scaffold degradation. Moreover, there is known data indicating higher thrombosis rate with the Absorb BVS compared with the new generation of DES, despite similar cardiovascular death. In this review, we discuss the clinical procedural and technical evidence on BVS, with emphasis on their clinical impact. We finally tackle the future directions on device and procedural improvement while asking: is the bioresorbable technology still the way to the future?

Thoracic aortic disease: Can we safely cover the branches?

Thoracic aortic disease has usually been treated with surgery. Thoracic endovascular aortic repair is challenging if supra-aortic vessels are involved. In situ fenestration of the main graft from a retrograde approach while using bare-metal stents as bridge stents appears to be a safe and practical technique.

Does single-valve surgery cause ischemia?

Isolated valve surgery is associated with a small incidence of postoperative PCI. PCI after single-valve surgery is associated with elevated mortality and morbidity risk. Possible mechanisms for cardiac ischemia include iatrogenic causes (such as suture-related or air embolism), intimal hyperplasia, and immunologic reaction to the valve prosthesis.

TAVI: How to best predict postprocedural outcomes?

Baseline risk scores for TAVI patients, including STS and EuroSCORE, might not predict long-term outcomes. Including postprocedural data might improve risk stratification. The ACEF-7 risk score includes the lowest creatinine clearance in the first 7 postprocedural days and appears to be a good predictor of worse long-term outcomes.

Myocardial fibrosis and MitraClip: Does it even matter?

Preprocedural myocardial fibrosis as identified by magnetic resonance imaging correlates with worse outcomes after MitraClip placement. Post-MitraClip mitral regurgitation gradient >2 or ischemic cardiomyopathy also correlates with worse outcomes. In the literature, other variables are mentioned (e.g., severe tricuspid regurgitation, atrial fibrillation, postoperative mitral valve area and/or gradient) that correlate with worse post-MitraClip outcomes.

Delivery catheters: Do they truly make a difference in transcatheter pulmonary valve replacement?

Transcatheter pulmonary valve replacement (TPVR) is a safe and feasible procedure for treating pulmonary stenosis, failed right ventricular conduits, or failed bioprosthetic valves. The medtronic melody valve and the Edwards Sapien XT and S3 valves have been the main prosthetic valves used in TPVR. Using the GORE DrySeal sheath helps valve delivery and facilitates TPVR.

Aortic dissection: Is the false lumen really important?

Aortic dissection is associated with a high mortality rate and has been increasingly treated with endovascular therapy. False lumen (FL) patency has been shown to be associated with worse outcomes. FL interventions that incorporate the FLIRT (FL intervention to promote remodeling and thrombosis) concept have been associated with improved aortic remodeling that may confer favorable long-term outcomes.

Use of an AFX aortic cuff in the endovascular treatment of aortocaval fistula secondary to abdominal aortic pseudoaneurysm.

Aortocaval fistula (ACF) is rare and lethal and can be either primary (due to an enlarged abdominal aortic aneurysm) or secondary (iatrogenic or secondary to abdominal surgery) in origin. We describe a case of an ACF secondary to a ruptured abdominal aortic pseudoaneurysm that we successfully treated with a planned endovascular approach using an AFX aortic cuff on both the arterial and venous sides.

Peripheral artery disease: How do genes and pharmacology interplay?

In patients with peripheral artery disease, high on-treatment platelet reactivity (HoTPR) might be associated with worse outcomes for those taking clopidogrel, but not for those taking aspirin. Certain genetic polymorphisms might account for HoTPR. Current literature supports the importance of antiplatelet therapy in treating patients with PAD with clopidogrel, aspirin, or both.

Plug vs. suture: Who wins in large bore access closure?

Large Bore Access in increasingly common and surgical closure used to be the gold standard for closure. Novel less invasive closure devices such as the suture based vascular devices offer a safe alternative to surgery. Recent developments provide us with MANTA (Essential Medical Inc., Malvern, Pennsylvania) a vascular closure device that seems to be as safe and associated with less bleeding. Certain genetic polymorphisms might account for HoTPR.

Chronic total occlusion: Does anti-platelet choice impact outcomes?

Chronic total occlusion (CTO) is associated with worse outcomes compared to non CTO percutaneous coronary intervention (PCI). CTO might be associated with vasomotor dysfunction Ticagrelor is a novel P2Y12 inhibitor that increases local adenosine The TIGER-BVS trial plans to assess the impact of using ticagrelor vs. clopidogrel on vasomotor activity and outcomes after successful CTO PCI.

"ICE or not to ICE during LAAO?" What are the benefits and disadvantages of ICE during LAAO?

For left atrial appendage occlusion (LAAO), intracardiac echocardiography (ICE) could be a safe alternative to transesophageal echocardiography (TEE). ICE obviates the need for general anesthesia and can be readily implemented in practice. Randomized controlled trials are needed to assess the noninferiority of ICE to TEE for LAAO.

A cardiologist's nightmare: Coronary obstruction during transcatheter aortic valve implantation: How to identify patients at highest risk for this complication.

Transcatheter aortic valve implantation (TAVI) is associated with several complications including coronary obstruction (CO) CO occurs in ∼1% of patients and mostly in patients receiving the SAPIEN XT valve Possible predictors of CO include coronary height <10 mm and aortic sinus diameter of <30 mm.

Drug-coated balloons: "Do they still have a role in treating coronary artery disease?"

Small vessels with coronary artery disease (CAD) are at high risk of restenosis, despite the use of drug-eluting stents (DESs). Drug-coated balloon (DCB) therapy offers a viable alternative to DESs for the management of small vessel CAD. The literature regarding the use of DCBs in lieu of the newer generation DESs to treat small vessel CAD is controversial.

"To close or not to close?" When should vascular closure devices be used after cardiac catheterization procedures?

Vascular closure devices (VCD) appear to be safe when compared to manual compression or surgical closure. VCDs' main advantage seems to stem from lower time to hemostasis (TTH) and time to mobilization. In anticoagulated patients with 6-Fr femoral sheaths, the new Celt ACT VCD, which uses a stainless-steel permanent implant, seems to be safe and decreases TTH when compared to manual pressure.

Plasmapheresis in severe methemoglobinemia following occupational exposure.

Ferrous iron can be converted to ferric iron by oxidative stress which results in the formation of methemoglobin. Consequently, the oxygen dissociation curve is shifted to the left, which leads to tissue hypoxia and ultimately may cause death. Acquired methemoglobinemia can be due to a host of offending agents and chemicals including nitrites, local anesthetics, aniline and antimalarial drugs. There are several approaches to the management of methemoglobinemia. The first step is to stop the offending agent and initiate supportive measures. Methylene blue can be used successfully provided the patient has no evidence of glucose 6 phosphate deficiency. Hyperbaric oxygen and intravenous ascorbic acid are other treatment options. We present a case of unusually severe methemoglobinemia (82% methemoglobin) secondary to occupational exposure that failed to respond to several lines of management including methylene blue, red cell exchange, intravenous ascorbic acid, and hyperbaric oxygen. However, the patient responded swiftly to plasmapheresis started upon suspicion of concomitant thrombotic thrombocytopenic purpura, and he subsequently recovered completely. Thus, plasmapheresis may have a role in severe methemoglonbinemia unresponsive to standard treatment options.

Accuracy and validation of an automated electronic algorithm to identify patients with atrial fibrillation at risk for stroke.

BACKGROUND: There is no universally accepted algorithm for identifying atrial fibrillation (AF) patients and stroke risk using electronic data for use in performance measures. METHODS: Patients with AF seen in clinic were identified based on International Classification of Diseases, Ninth Revision(ICD-9) codes. CHADS(2) and CHA(2)DS(s)-Vasc scores were derived from a broad, 10-year algorithm using IICD-9 codes dating back 10 years and a restrictive, 1-year algorithm that required a diagnosis within the past year. Accuracy of claims-based AF diagnoses and of each stroke risk classification algorithm were evaluated using chart reviews for 300 patients. These algorithms were applied to assess system-wide anticoagulation rates. RESULTS: Between 6/1/2011, and 5/31/2012, we identified 6,397 patients with AF. Chart reviews confirmed AF or atrial flutter in 95.7%. A 1-year algorithm using CHA(2)DS(2)-Vasc score ≥2 to identify patients at risk for stroke maximized positive predictive value (97.5% [negative predictive value 65.1%]). The PPV of the 10-year algorithm using CHADS(2) was 88.0%; 12% those identified as high-risk had CHADS(2) scores <2. Anticoagulation rates were identical using 1-year and 10-year algorithms for patients with CHADS(2) scores ≥2 (58.5% on anticoagulation) and CHA(2)DS(2)-Vasc scores ≥2 (56.0% on anticoagulation). CONCLUSIONS: Automated methods can be used to identify patients with prevalent AF indicated for anticoagulation but may have misclassification up to 12%, which limits the utility of relying on administrative data alone for quality assessment. Misclassification is minimized by requiring comorbidity diagnoses within the prior year and using a CHA(2)DS(2)-Vasc based algorithm. Despite differences in accuracy between algorithms, system-wide anticoagulation rates assessed were similar regardless of algorithm used.

Cardiac Arrest as First Presentation of Thyroid Storm.

Thyroid storm is a life-threatening condition characterized by a high level of circulating thyroid hormones and harbors high mortality and morbidity, even if diagnosed and treated early. The condition is frequently overlooked and under-recognized in emergency departments owing to its rarity. Here, we present a case of a 24-year-old male patient, previously healthy, who presented with cardiac arrest and was found to have heart failure and high thyroid hormone levels after investigations. Consequently, the presentation was attributed to thyroid storm. His clinical status and cardiac function improved after treatment of the hyperthyroidism.