2021 ACC/AHA/SCAI Guideline for Coronary Artery Revascularization: Executive Summary: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines.

AIM: The executive summary of the American College of Cardiology/American Heart Association/Society for Cardiovascular Angiography and Interventions coronary artery revascularization guideline provides the top 10 items readers should know about the guideline. In the full guideline, the recommendations replace the 2011 coronary artery bypass graft surgery guideline and the 2011 and 2015 percutaneous coronary intervention guidelines. This summary offers a patient-centric approach to guide clinicians in the treatment of patients with significant coronary artery disease undergoing coronary revascularization, as well as the supporting documentation to encourage their use. METHODS: A comprehensive literature search was conducted from May 2019 to September 2019, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Collaboration, CINHL Complete, and other relevant databases. Additional relevant studies, published through May 2021, were also considered. Structure: Recommendations from the earlier percutaneous coronary intervention and coronary artery bypass graft surgery guidelines have been updated with new evidence to guide clinicians in caring for patients undergoing coronary revascularization. This summary includes recommendations, tables, and figures from the full guideline that relate to the top 10 take-home messages. The reader is referred to the full guideline for graphical flow charts, supportive text, and tables with additional details about the rationale for and implementation of each recommendation, and the evidence tables detailing the data considered in the development of this guideline.

Association of ACEI/ARB and statin prescribing patterns with mortality after Transcatheter Aortic Valve Replacement (TAVR): Findings from real-world claims data.

BACKGROUND: Transcatheter aortic valve replacement (TAVR) has become the standard of care for most patients with severe aortic stenosis (AS), but the impact of medical therapy prescribing patterns on post-TAVR patients has not been thoroughly investigated. METHODS: We analyzed Optum claims data from 9,012 adults who received TAVR for AS (January 2014-December 2018). Pharmacy claims data were used to identify patients who filled ACEI/ARB and/or statin prescriptions during the study's 90-day landmark period post-TAVR. Kaplan-Meier and adjusted Cox Proportional Hazards models were used to evaluate the association of prescribing patterns with mortality during the 3-year follow-up period. Subgroup analyses were performed to examine the impact of 11 potential confounders on the observed associations. RESULTS: A significantly lower adjusted 3-year mortality was observed for patients with post-TAVR prescription for ACEI/ARBs (hazard ratio [HR] = 0.82, 95% confidence interval [CI] 0.74-0.91, P = .0003) and statins (HR = 0.85, 95% CI 0.77-0.94, P = .0018) compared to patients who did not fill prescriptions for these medications post-TAVR. Subgroup analyses revealed that the survival benefit associated with ACEI/ARB prescription was not affected by any of the potential confounding variables, except preoperative ACEI/ARB prescription was associated with significantly lower risk of mortality vs postoperative prescription only. No other subgroup variables had significant interactions associated with survival benefits, including preoperative use of statins. CONCLUSIONS: In this large-scale, real-world analysis of patients undergoing TAVR, the prescription of ACEI/ARB and statins was associated with a significantly lower risk of mortality at 3-years, especially in those where the medications were initiated preoperatively.

Increased prescription dose for large vessel intravascular brachytherapy.

BACKGROUND: Most randomized studies testing the effectiveness of IVBT were limited to vessels less than 4 mm diameter. In fact, it is now common to treat vessels larger than 4 mm. Accordingly, the authors instituted a prescription dose increase to 34 Gy at 2 mm from source center for vessels greater than 4.0 mm. The increase in prescription dose to 34 Gy at 2 mm from center is substantial, being 50% higher than the conventional maximum of 23 Gy. AIM: To take a close look at group of patients treated to 34 Gy, and for whom follow-up angiograms are available. METHODS: Ten patients treated for ISR with a prescription dose of 34 Gy and for whom follow-up angiograms were available were studied. Beta-radiation brachytherapy was performed with a Novoste Beta-Cath System using a strontium-90 (beta) source (Best Vascular, Springfield, VA). Source lengths of 40 or 60 mm were used. A dose of 34 Gy was prescribed at 2 mm from the source center. RESULTS: Patients were re-catheterized from 2 to 21 months (median: 16 months) following IVBT, all for symptoms suggested of restenosis. All patients had some degree of ISR of the target vessel, but no IVBT-treated vascular segment showed angiographic signs of degeneration, dissection or aneurysm. CONCLUSION: The authors' clinical impression, along with detailed review of the 10 cases, suggest that using a 34 Gy prescription dose at 2 mm from source center does not result in increased toxicity.

ACGME Interventional Cardiology Milestones 2.0-an overview: Endorsed by the Accreditation Council for Graduate Medical Education.

This document provides an overview of the rationale, development, interpretation, and practical suggestions for implementation of the new Accreditation Council for Graduate Medical Education (ACGME) Interventional Cardiology (IC) Milestones 2.0. Previously, IC programs used the general ACGME Milestones for internal medicine. The IC Milestones version 2.0 updates the ACGME competencies to be specific to training in IC. In 2019 an ACGME working group consisting of IC program directors, a lay representative, and representatives from the American Board of Internal Medicine met to develop the IC Milestones version 2.0. The ACGME IC Milestones 2.0 establishes a framework for formative feedback for trainees within domains of patient care, medical knowledge, systems-based practice, practice-based learning and improvement, professionalism, and interpersonal and communication skills. The 2021 IC Milestones 2.0 provides a framework for IC mentors and trainees to identify areas for improvement or commendation help stimulate meaningful educational discussions, and provide the basis for self-reflection and self-improvement.

Failure patterns after intravascular brachytherapy for in-stent coronary restenosis.

INTRODUCTION: One strategy to improve the effectiveness of intravascular brachytherapy (IVBT) is to study its failures. Previous investigations described mostly discrete, focal recurrences, typically at the proximal or distal edges of the irradiated segment after plain angioplasty or bare metal stents. We reviewed failure patterns of 30 unselected drug-eluting stent (DES) patients who had follow-up angiograms for recurrence within their IVBT-treated vessel. METHODS: Records of 53 unselected IVBT patients treated between 2016 and 2021 were reviewed. Thirty of the 53 patients had at least one subsequent percutaneous intervention (PCI) for in-stent restenosis (ISR) after IVBT. Angiographic findings of those 30 patients with ISR within their previously irradiated vessel are reported here. RESULTS: Of the 30 patients, 21 (70%) developed recurrent ISR within the irradiated segment. Six of the 21 patients who failed within the irradiated segment also experienced ISR proximal or distal to the irradiated segment. Only 15 patients (50%) failed exclusively within the irradiated segment. In nine patients (30%), restenosis occurred proximally and/or distally to the irradiated segment, but not inside of the irradiated segment itself. CONCLUSIONS: We have shown here that 50% of failures after coronary IVBT for DES ISR occur exclusively within the irradiated segment. An additional 20% of patients had failure within and outside of the irradiated segment. These percentages suggest that a higher radiation dose might improve the long-term patency rates, a conclusion that should be tempered by the lack of universal follow-up.

Interventional cardiologists' perceptions of percutaneous coronary intervention quality measurement and feedback.

BACKGROUND: Interventional cardiologists receive feedback on their clinical care from a variety of sources including registry-based quality measures, case conferences, and informal peer interactions. However, the impact of this feedback on clinical care is unclear. METHODS: We interviewed interventional cardiologists regarding the use of feedback to improve their care of percutaneous coronary intervention (PCI) patients. Interviews were assessed with template analysis using deductive and inductive techniques. RESULTS: Among 20 interventional cardiologists from private, academic, and Department of Veterans Affairs practice, 85% were male, 75% performed at least 100 PCIs annually, and 55% were in practice for 5 years or more. All reported receiving feedback on their practice, including formal quality measures and peer learning activities. Many respondents were critical of quality measure reporting, citing lack of trust in outcomes measures and poor applicability to clinical care. Some respondents reported the use of process measures such as contrast volume and fluoroscopy time for benchmarking their performance. Case conferences and informal peer feedback were perceived as timelier and more impactful on clinical care. Respondents identified facilitators of successful feedback interventions including transparent processes, respectful and reciprocal peer relationships, and integration of feedback into collective goals. Hierarchy and competitive environments inhibited useful feedback. CONCLUSIONS: Despite substantial resources dedicated to performance measurement and feedback for PCI, interventional cardiologists perceive existing quality measures to be of only modest value for improving clinical care. Catherization laboratories should seek to integrate quality measures into a holistic quality program that emphasizes peer learning, collective goals and mutual respect.

Outcomes of urgent/emergent transcatheter mitral valve repair (MitraClip): A single center experience.

OBJECTIVES: To describe the outcomes of urgent/emergent transcatheter edge-to-edge mitral valve repair (TMVr) and compare the clinical, echocardiographic, and procedural characteristics of survivors and nonsurvivors. BACKGROUND: TMVr is a treatment strategy for select patients with severe primary or secondary mitral regurgitation. However, knowledge regarding outcomes for urgent/emergent TMVr is limited. METHODS: All urgent or emergent TMVr procedures using MitraClip performed at the University of Washington Medical Center between January 2018 and March 2019 were identified and clinical, echocardiographic, hemodynamic, procedural, and outcomes data were obtained by chart review. Outcomes included all-cause mortality, hospital mortality, procedural success, periprocedural complications, and hospital readmission. RESULTS: Of the 20 patients who underwent urgent/emergent TMVr, eight were treated for cardiogenic shock (CS), four for acute decompensated heart failure (ADHF) with hypoxemic respiratory failure requiring mechanical ventilation, and eight for ADHF with failure of inpatient medical therapy. Mechanical circulatory support (MCS) was used in six patients; preceding TMVr in three patients and immediately post-TMVr in three patients. Overall, 30-day mortality and hospital readmission rates were 21 and 13%, respectively. Over a median 153 days (IQR 20-491) of follow-up, 10 patients (50%) died. Preprocedure CS, new or ongoing MCS post-TMVr, refractory respiratory failure post-TMVr, and acute kidney injury post-TMVr were associated with mortality. CONCLUSIONS: In a single-center retrospective analysis, urgent/emergent TMVr in high-risk patients with ADHF or CS was associated with high short-term mortality and periprocedural complications. Prospective studies are warranted to inform patient selection and periprocedural management for urgent/emergent TMVr.

Feasibility and safety of orbital atherectomy for the treatment of in-stent restenosis secondary to stent under-expansion.

BACKGROUND: Debulking and ablative techniques are sometimes used for the treatment of in-stent restenosis (ISR) secondary to resistant stent under-expansion (SU). The safety and effectiveness of orbital atherectomy (OA) in this cohort of patients has not been reported. METHODS: We retrospectively evaluated consecutive patients treated with OA for ISR secondary to balloon undilatable SU at two academic tertiary care centers between October 2016 and June 2019. Angiographic or intravascular imaging identified SU. Technical success was defined as residual 0% stenosis with TIMI III flow. RESULTS: A total of 41 patients were included in the study. Patients had an average age of 65 ± 12 years; 73% male, 61% diabetic, 41% with prior coronary artery bypass grafting, 61% with a prior incident of ISR, 51% presented with stable angina, 17% unstable angina, and 32% non-ST elevation myocardial infarction (MI). Implantation of the under-expanded stents occurred between 2 months and 22 years prior to the index procedure. A total of 27% of patients had multiple layers of stents in the target lesion and 32% of patients had in-stent chronic total occlusion. Technical success was achieved in 40 (98%) patients. There were 2 (5%) major adverse cardiovascular events; both of them were periprocedural MI from the no-reflow phenomenon. There were 2 (5%) Ellis type II coronary perforations that required no intervention. CONCLUSIONS: OA can be effectively performed as an adjunctive tool in the treatment of ISR with balloon undilatable SU. The use of OA for SU is not approved by the U.S. Food and Drug Administration and is "off label" and caution must be used to limit any device/stent interaction.

Distribution of C-arm projections in native and bioprosthetic aortic valves cusps: Implication for BASILICA procedures.

OBJECTIVES: We sought to document aortic cusps fluoroscopic projections and their distributions using leaflet alignment which is a novel concept to optimize visualization of leaflets and for guiding BASILICA (bioprosthetic or native aortic scallop intentional laceration to prevent coronary artery obstruction) and determine whether these projections were feasible in catheter laboratory. BACKGROUND: Optimal fluoroscopic projections of aortic valve cusps have not been well described. METHODS: A total of 128 pre-transcatheter aortic valve replacement (pre-TAVR) computed tomographies (CT) (72 native valves and 56 bioprosthetic surgical valves) were analyzed. Using CT software (3Mensio, Pie medical imaging, the Netherlands), leaflet alignment was performed and the feasibility of these angles, which were defined as rate of obtainable with efforts (within LAO/RAO of 85° and CRA/CAU of 50°) were evaluated. RESULTS: High feasibility was seen in right coronary cusp (RCC) front view (100%) and left coronary cusp (LCC) side view (99.2%), followed by noncoronary cusp side view (95.3%). In contrast, low feasibility of RCC side view (7.8%) and LCC front view (47.6%) was observed. No statistical differences were seen between the distribution of native valves and bioprosthetic surgical valves. With patient/table tilt of 20°LAO and 10°CRA, the feasibility of RCC side view and LCC front view increased to 43.7 and 85.2%, respectively. CONCLUSION: Distributions of each cusp's leaflet alignment follows "sigmoid curve" which can provide better understanding of aortic valve cusp orientation in TAVR and BASILICA. RCC side view used in right cusp BASILICA is commonly unachievable in catheter laboratory and may improve with patient/table tilt.

Human embryonic-stem-cell-derived cardiomyocytes regenerate non-human primate hearts.

Pluripotent stem cells provide a potential solution to current epidemic rates of heart failure by providing human cardiomyocytes to support heart regeneration. Studies of human embryonic-stem-cell-derived cardiomyocytes (hESC-CMs) in small-animal models have shown favourable effects of this treatment. However, it remains unknown whether clinical-scale hESC-CM transplantation is feasible, safe or can provide sufficient myocardial regeneration. Here we show that hESC-CMs can be produced at a clinical scale (more than one billion cells per batch) and cryopreserved with good viability. Using a non-human primate model of myocardial ischaemia followed by reperfusion, we show that cryopreservation and intra-myocardial delivery of one billion hESC-CMs generates extensive remuscularization of the infarcted heart. The hESC-CMs showed progressive but incomplete maturation over a 3-month period. Grafts were perfused by host vasculature, and electromechanical junctions between graft and host myocytes were present within 2 weeks of engraftment. Importantly, grafts showed regular calcium transients that were synchronized to the host electrocardiogram, indicating electromechanical coupling. In contrast to small-animal models, non-fatal ventricular arrhythmias were observed in hESC-CM-engrafted primates. Thus, hESC-CMs can remuscularize substantial amounts of the infarcted monkey heart. Comparable remuscularization of a human heart should be possible, but potential arrhythmic complications need to be overcome.

Outcomes of Emergency Transcatheter Aortic Valve Replacement.

OBJECTIVE: To identify outcomes of patients undergoing emergency transcatheter aortic valve replacement (TAVR) and determine predictors of in-hospital mortality. BACKGROUND: Emergency TAVR has emerged as a viable treatment strategy for patients with decompensated severe aortic stenosis and/or regurgitation; however, data on patients undergoing emergency TAVR are limited. METHODS: All emergency TAVR procedures were identified from a single tertiary academic center between January 2015 and August 2018. RESULTS: 31 patients underwent emergency TAVR due to cardiogenic shock (26 patients), electrical instability with incessant ventricular tachycardia (2 patients), severe refractory angina (2 patients), and decompensated heart failure with hypoxemic respiratory failure requiring mechanical ventilation (1 patient). Mechanical circulatory support (MCS) was used in 16 (51.6%). MCS initiation occurred immediately prior to TAVR in 10 patients and placed post-TAVR in 6 patients. 6 patients died before hospital discharge (in-hospital mortality 19.4%). 1-year and 2-year survival rates were 61.0% and 55.9%, respectively. Univariate predictors of in-hospital mortality were preprocedural pulmonary artery pulsatility index (PAPi) ≤1.8 (66.7% vs. 20.0%, p=0.01), intraprocedural cardiopulmonary resuscitation (CPR) (83.3% vs 4.0%, p ≤ 0.001), acute kidney injury post-TAVR (80.0% vs. 4.2%, p ≤ 0.001), initiation of dialysis post-TAVR (60.0% vs. 4.2%, p ≤ 0.001), and MCS initiation post-TAVR (50.0% vs. 12.0%, p=0.03). MCS initiation before TAVR was associated with improved survival compared with post-TAVR initiation. CONCLUSION: Emergency TAVR in extreme risk patients with acute decompensated heart failure or cardiogenic shock secondary to severe aortic valve disease is associated with high in-hospital mortality rates. Careful patient selection taking into account right heart function, assessed by PAPi, and early utilization of MCS may improve survival following emergency TAVR.

Reversible thrombotic aortic valve restenosis after valve-in-valve transcatheter aortic valve replacement.

Thrombotic aortic valve restenosis following transcatheter aortic valve replacement (TAVR) has not been extensively reported and the rates of TAVR valve thrombosis are not known. We present three cases of valve-in-valve (VIV) restenosis following TAVR with the balloon expandable transcatheter heart valves, presumably due to valve thrombosis that improved with anticoagulation. © 2016 Wiley Periodicals, Inc.

Overexpansion of the 29 mm SAPIEN 3 transcatheter heart valve in patients with large aortic annuli (area > 683 mm2 ): A case series.

OBJECTIVES: To evaluate overexpanded 29 mm SAPIEN (S3) transcatheter heart valves in patients with aortic annuli area >683 mm2 . BACKGROUND: The largest valve area the 29 mm S3 is specified for is 683 mm2 . Valve overexpansion has been performed in patients with larger aortic annuli, but data are limited. Moreover, feasibility in areas >740 mm2 is unknown. METHODS: All 29 mm S3 transcatheter aortic valve replacements (TAVR) at a single center over 23-months were retrospectively reviewed. Patients with annulus areas >683 mm2 were included. Immediate post-TAVR hemodynamics and transthoracic echocardiography (TTE) findings on post-TAVR day-1 and day-30 were recorded. RESULTS: Of 81 29 mm S3 TAVR cases, 3 (3.7%) met inclusion criteria (patients 1, 2, and 3 had CT-scan derived areas of 748.1 mm2 , 793 mm2 , and 787 mm2 , respectively). Annular eccentricity index ranged from 0.12 to 0.25. All underwent transfemoral TAVR with 29 mm S3 valves overexpanded using +4 mL of contrast. Post-dilatation with +5 mL was performed in patient 2. The average valve shortening was 10.68 mm. On day 1, patients 1 and 2 had trace and mild paravalvular leak (PVL) (respectively), whereas, patient 3 had mild-moderate PVL. Patient 1 was also noted to have trace central AR on day 1. No other central AR was noted. Immediate post-procedure aortic regurgitation (AR) index in patients 1, 2, and 3 was 43, 34, and 33 respectively. At 30 days, AR was completely resolved in patient 1, whereas AR severity in patients 2 and 3 remained similar. No patients had > moderate AR at any point during follow-up. No valve migration or embolization occurred. Patient 1 required a permanent pacemaker. No other major complications were noted. All patients were clinically stable at 30 days. CONCLUSIONS: TAVR using overexpanded 29 mm S3 in valve areas >740 mm2 (up to 793 mm2 ) seemed to be safe and feasible in our small series. Further study in a larger series is needed to determine clinical outcomes in this patient population.

Left ventricular end-diastolic pressure as an independent predictor of outcome during balloon aortic valvuloplasty.

OBJECTIVES: In this study, we examined the predictive value of the left ventricular end-diastolic pressure (LVEDP) in patients undergoing balloon aortic valvuloplasty (BAV). BACKGROUND: The LVEDP is a useful indicator of hemodynamic status in patients with severe aortic stenosis. In BAV, decompensated heart failure is associated with worse outcomes. METHODS: We identified all consecutive patients with severe symptomatic aortic stenosis who underwent retrograde BAV at the Massachusetts General Hospital from 2004 to 2008. Patients were stratified and compared according to their baseline LVEDP into ≤15 mm Hg, 16-20 mm Hg, 21-25 mm Hg, and ≥26 mm Hg. Procedural and in-hospital outcomes and adverse events were compared. Multivariate logistic regression was used for the adjusted analysis. RESULTS: A total of 111 patients with a mean age of 83±11 years underwent BAV. Of these, the LVEDP was ≤15 mm Hg in 29 (26%), 16-20 mm Hg in 41 (37%), 21-25 mm Hg in 16 (14%), and ≥26 mm Hg in 25 (23%) patients. Baseline characteristics were similar among the four groups. Noticeably, patients with high LVEDP levels had significantly higher rates of the combined endpoint of in-hospital death, myocardial infarction (MI), cardiopulmonary arrest, and tamponade was P = 0.02. Periprocedural MI was more common among those with higher LVEDP (16% vs. 2.3%; P = 0.04). Multivariate analysis revealed LVEDP (OR 1.08, for each mm Hg increase in pressure, 95 % CI 1.02-1.14), small LV chamber size, and New York Heart Association class as independent predictors of adverse outcomes. CONCLUSIONS: The LVEDP is an important independent predictor of poor in-hospital outcome during BAV. In these patients, the immediate hemodynamic status may be more important than the baseline left ventricular systolic function. Hemodynamic optimization before or during BAV should be considered and may be beneficial.

Extreme coronary radiation doses from intravascular brachytherapy.

PURPOSE: To evaluate coronary artery integrity after very high radiation doses from intravascular brachytherapy (IVBT) in the setting of source asymmetry. METHODS: Ten patients treated for right coronary artery (RCA) in-stent restenosis (ISR) between 2017 and 2021 and for whom follow-up angiograms were available were identified from departmental records. Procedural angiograms, taken to document source position, were used to estimate vascular wall doses. The 2.5 mm proximal source marker was used to estimate the distance from source center to the media and adventitia. Distances were converted to dose (Gy) using the manufacturers' dose fall-off table, measured in water. Follow-up films were scrutinized for any sign of late vascular damage. RESULTS: The average minimal distance from catheter center to the adjacent media and the adventitia was 0.9 mm (±0.2) mm and 1.4 mm (±0.2), respectively. The average maximum media and adventitial doses adjacent to the source were 75 Gy (±26) and 39 Gy (±14), respectively. Follow-up angiograms were available from 0.6 years to 3.9 years following IVBT (median: 1.6 years). No IVBT-treated vascular segment showed signs of degeneration, dissection or aneurysm. CONCLUSION: IVBT vascular wall doses are frequently far higher than prescribed. The lack of complications in this unselected group of patients gives a modicum of reassurance that raising the prescription dose is unlikely to lead to a sudden appearance of complications.

Improving survival and efficacy of pluripotent stem cell-derived cardiac grafts.

Human embryonic stem cells (hESCs) can be differentiated into structurally and electrically functional myocardial tissue and have the potential to regenerate large regions of infarcted myocardium. One of the key challenges that needs to be addressed towards full-scale clinical application of hESCs is enhancing survival of the transplanted cells within ischaemic or scarred, avascular host tissue. Shortly after transplantation, most hESCs are lost as a result of multiple mechanical, cellular and host factors, and a large proportion of the remaining cells undergo apoptosis or necrosis shortly thereafter, as a result of loss of adhesion-related signals, ischaemia, inflammation or immunological rejection. Blocking the apoptotic signalling pathways of the cells, using pro-survival cocktails, conditioning hESCs prior to transplant, promoting angiogenesis, immunosuppressing the host and using of bioengineered matrices are among the emerging techniques that have been shown to optimize cell survival. This review presents an overview of the current strategies for optimizing cell and host tissue to improve the survival and efficacy of cardiac cells derived from pluripotent stem cells.

Diagnostic time course, treatment, and in-hospital outcomes for patients with ST-segment elevation myocardial infarction presenting with nondiagnostic initial electrocardiogram: a report from the American Heart Association Mission: Lifeline program.

BACKGROUND: Prior studies indicate that a subset of patients diagnosed as having ST-segment elevation myocardial infarction (STEMI) will have an initial non-diagnostic electrocardiogram (ECG) during evaluation. However, the timing of diagnostic ECG changes in this group is unknown. Our primary aim was to describe the timing of ECG diagnosis of STEMI in patients whose initial ECG was non-diagnostic. Secondarily, we sought to compare the delivery of American College of Cardiology/American Heart Association guidelines-based care and in-hospital outcomes in this group compared with patients diagnosed as having STEMI on initial ECG. METHODS: We analyzed data from 41,560 patients diagnosed as having STEMI included in the National Cardiovascular Data Registry ACTION Registry-GWTG from January 2007 to December 2010. We divided this study population into 2 groups: those diagnosed on initial ECG (N = 36,994) and those with an initial non-diagnostic ECG that were diagnosed on a follow-up ECG (N = 4,566). RESULTS: In general, baseline characteristics and clinical presentations were similar between the 2 groups. For patients with an initial non-diagnostic ECG, 72.4% (n = 3,305) had an ECG diagnostic for STEMI within 90 minutes of their initial ECG. There did not appear to be significant differences in the administration of guideline-recommended treatments for STEMI, in-hospital major bleeding (P = .926), or death (P = .475) between these groups. CONCLUSIONS: In a national sample of patients diagnosed as having STEMI, 11.0% had an initial non-diagnostic ECG. Of those patients, 72.4% had a follow-up diagnostic ECG within 90 minutes of their initial ECG. There did not appear to be clinically meaningful differences in guidelines-based treatment or major inhospital outcomes between patients diagnosed as having STEMI on an initial ECG and those diagnosed on a follow-up ECG.

Image-guided intravascular brachytherapy dose escalation.

PURPOSE: Coronary stents reduce IVBT radiation dose with a single layer by 10-30%. However, the impact of multiple stent layers and stent expansion remains unexplored. Individualized dose adjustments considering variations in stent layers and expansion could improve radiation delivery effectiveness. METHODS: EGSnrc was used to compute the delivered vessel wall dose in various IVBT scenarios. Stent effects were modeled for the stent density of 25%, 50%, and 75% with 1, 2, and 3 layers respectively. Doses were calculated at 1.75 to 5.00 mm away from the source center, normalized to 100% at 2 mm. RESULTS: Dose fall-off increased with increasing stent density. With a single layer, the dose at 2 mm from source fell from 100% of prescription to 92%, 83% and 73% at 25%, 50% and 75% density, respectively. The computed dose to points with increasing radial distance from the source decreased progressively with increasing stent layers. With three layers, at 75% stent density, the dose at 2 mm from source center fell to 38%. CONCLUSIONS: A schema for image-guided IVBT dose adjustment is described. While it would be an improvement over current standard of care, myriad factors remain to be addressed in a comprehensive effort to optimize IVBT.

Rapid-exchange guide catheter extension for extending the reach of an AL3 guide in a patient with a long, dilated ascending aorta.

We describe the use of a rapid-exchange style guide catheter extension to facilitate diagnostic coronary angiography in a patient with a long, dilated ascending aorta. The guide catheter extension is an easy to use device that can extend the reach of 110 cm catheters. There are several advantages to this "mother and child" guide catheter extension over the traditional telescoping catheter approach.