Outcomes of retrograde chronic total occlusion percutaneous coronary intervention: A report from the OPEN-CTO registry.

OBJECTIVES: We sought to assess in-hospital and long-term outcomes of retrograde compared with antegrade-only percutaneous coronary intervention for chronic total occlusion (CTO PCI). BACKGROUND: Procedural and clinical outcomes following retrograde compared with antegrade-only CTO PCI remain unknown. METHODS: Using the core-lab adjudicated OPEN-CTO registry, we compared the outcomes of retrograde to antegrade-only CTO PCI. Primary endpoints included were in-hospital major adverse cardiac and cerebrovascular events (MACCE) (all-cause death, stroke, myocardial infarction [MI], emergency cardiac surgery, or clinically significant perforation) and MACCE at 1-year (all-cause death, MI, stroke, target lesion revascularization, or target vessel reocclusion). RESULTS: Among 885 single CTO procedures from the OPEN-CTO registry, 454 were retrograde and 431 were antegrade-only. Lesion complexity was higher (J-CTO score: 2.7 vs. 1.9; p < .001) and technical success lower (82.4 vs. 94.2%; p < .001) in retrograde compared with antegrade-only procedures. All-cause death was higher in the retrograde group in-hospital (2 vs. 0%; p = .003), but not at 1-year (4.9 vs. 3.3%; p = .29). Compared with antegrade-only procedures, in-hospital MACCE rates (composite of all-cause death, stroke, MI, emergency cardiac surgery, and clinically significant perforation) were higher in the retrograde group (10.8 vs. 3.3%; p < .001) and at 1-year (19.5 vs. 13.9%; p = .03). In sensitivity analyses landmarked at discharge, there was no difference in MACCE rates at 1 year following retrograde versus antegrade-only CTO PCI. Improvements in Seattle Angina Questionnaire Quality of Life scores at 1-year were similar between the retrograde and antegrade-only groups (29.9 vs 30.4; p = .58). CONCLUSIONS: In the OPEN-CTO registry, retrograde CTO procedures were associated with higher rates of in-hospital MACCE compared with antegrade-only; however, post-discharge outcomes, including quality of life improvements, were similar between technical modalities.

A CHIP fellow's transition into practice: Building a complex coronary therapeutics program.

BACKGROUND: Both the prevalence and complexity of coronary artery disease are on the rise in the United States, leading to a resurgence in novel techniques and equipment utilized to treat complex coronary disease. However, declining percutaneous coronary intervention (PCI) volumes and lack of formal post-graduate education opportunities have created a gap in treatment delivery for this patient population. Several complex, high-risk, and indicated PCI (CHIP) fellowships have been developed in an attempt to bridge this disparity. We present data from the first year of practice from a former CHIP fellow during development of a formal complex coronary therapeutics program. METHODS: Data was prospectively collected for PCIs performed during the first 12 months of practice for the lead author and compared to procedures performed in the 12 months prior to the study period. RESULTS: Out of 371 PCIs performed during the study period, 53.4% (198/371) were considered complex, including 126 chronic total occlusion (CTO) procedures. Compared to the previous 12 months, there was a significant increase in the number and complexity (median J-CTO score 2.1 vs. 1.3, p .04) of CTOs performed during the study period. CTO procedural characteristics and complication rates were similar to those previously published in large U.S. registries, with technical success in 93.4% (118/126) and procedural success in 85.7% (108/126). CONCLUSION: Following dedicated CHIP fellowship training and establishment of a formal CHIP program, procedural success and complication rates were achieved similar to those published in prior studies evaluating CTO PCI at high volume centers.

Point-of-Care Troponin Testing during Ambulance Transport to Detect Acute Myocardial Infarction.

Objective: Use of point-of-care (POC) troponin (cTn) testing in the Emergency Department (ED) is well established. However, data examining POC cTn measurement in the prehospital setting, during ambulance transport, are limited. The objective of this study was to prospectively test the performance of POC cTn measurement by paramedics to detect myocardial infarction (MI) among patients transported to the ED for acute chest pain. Methods: A prospective cohort study of adults with non-traumatic chest pain was conducted in three Emergency Medical Services agencies (December 2016 to January 2018). Patients with ST-elevation MI on ECG were excluded. During ambulance transport paramedics initiated intravenous access, collected blood, and used a POC device (i-STAT; Abbott Laboratories) to measure cTn. Following ED arrival, participants received standard evaluations including clinical blood draws for cTn measurement in the hospital central lab (AccuTnI +3 assay; Beckman Coulter, or cTnI-Ultra assay; Siemens). Blood collected during ambulance transport was also analyzed for cTn in the central lab. Index visit MI was adjudicated by 3 experts using central lab cTn measures from the patient's clinical blood draws. Test characteristics (sensitivity, specificity, and predictive values) for detection of MI were calculated for POC and central lab cTn measurement of prehospital blood and compared with McNemar's test. Results: During the study period prehospital POC cTn results were obtained on 421 patients, of which 5.0% (21/421) had results >99th percentile upper reference limit. MI was adjudicated in 16.2% (68/421) during the index visit. The specificity and positive predictive value of the POC cTn measurement were 99.2% (95% CI 97.5-99.8%) and 85.7% (95% CI 63.7-97.0%) for MI. However, the sensitivity and NPV of prehospital POC cTn were 26.5% (95% CI 16.5-38.6%) and 87.5% (95% CI 83.9-90.6%). Compared to POC cTn, the central lab cTn measurement of prehospital blood resulted in a higher sensitivity of 67.9% (95% CI 53.7-80.1%, p < 0.0001), but lower specificity of 92.4% (95% CI 88.4-95.4%, p = 0.0001). Conclusions: Prehospital POC i-STAT cTn measurement in patients transported with acute chest pain was highly specific for MI but had low sensitivity. This suggests that prehospital i-STAT POC cTn could be useful to rule-in MI, but should not be used to exclude MI.

Intravascular lithotripsy-assisted Impella insertion: A case report.

Coronary and peripheral arterial calcification increases the complexity of percutaneous treatment strategies in both coronary and peripheral interventions. The first use of intravascular lithotripsy (IVL) using the Shockwave IVL device (Shockwave Medical Inc) in femoropopliteal arteries for modification of calcified plaque was recently described. We present a case illustrating use of the device to deliver a 14 French sheath for delivery of an Impella mechanical circulatory device prior to high-risk percutaneous coronary intervention (PCI). This case illustrates that IVL may be used to facilitate a broadening array of procedures in the catheterization laboratory, including the delivery of large bore sheathes.

Algorithmic solutions to common problems encountered during chronic total occlusion angioplasty: The algorithms within the algorithm.

Improved technical equipment, dissemination of best practices, and the importance of complete coronary revascularization have led to a renewed interest in coronary chronic total occlusion (CTO) PCI. In particular, the hybrid algorithm has been associated with increasing procedural success rates in the US. However, the hybrid algorithm only covers overarching strategies in the overall approach to these lesions. Several technical challenges can occur during execution of these approaches, each of which has several potential solutions. A systematic or algorithmic approach to dealing with these challenges could contribute to improved procedural efficiency and higher procedural success. While there have been isolated attempts in the past to codify approaches to each of these situations, there has not been a contemporary, comprehensive review of the potential solutions to these problems. We present 10 common problems encountered during CTO PCI and a consensus hierarchical approach to them.

Impella-assisted chronic total occlusion percutaneous coronary interventions: A multicenter retrospective analysis.

INTRODUCTION: Patients with coronary chronic total occlusions (CTO) often have concurrent higher-risk anatomy and physiology (significant calcium, left ventricular dysfunction, multivessel disease) that increase their procedural risk. We present a retrospective multicenter case series describing use of the Impella percutaneous ventricular assist device (p-VAD) during CTO PCI. METHODS: We performed a retrospective analysis of self-reported data from five large referral centers from 2013 to 2017 and identified patients that underwent elective, hemodynamically supported CTO PCI with the Impella p-VAD device (2.5 or CP). Preprocedural demographics, procedural invasive hemodynamics and characteristics, and in-hospital outcomes were reported. RESULTS: About 57 patients (2% of the overall CTO volume of these centers) were included in this retrospective cohort. The primary indication in the majority (78.9%) of cases was chronic angina; in 21.1% the primary indication was for chronic congestive heart failure because of an ischemic cardiomyopathy. The median LVEF was 20% (15%, 30%) and 63.2% were surgical turndowns. Significant proportions of the group underwent multivessel PCI (91.2%), intervention on an unprotected left main or last remaining conduit vessel (35.1%), and/or atherectomy (17.5%). Technical success was 87.7%. In-hospital procedural complications included: vascular injury (5.3%), all-cause death (5.3%), major bleeding (3.5%), stroke (1.8%), and coronary perforation resulting in tamponade (1.8%). CONCLUSION: Impella-assisted CTO PCI can be performed with high technical success rates. However, assiduous attention to appropriate case selection is critical, given the periprocedural complication rates reported in this patient population.

Subadventitial stenting around occluded stents: A bailout technique to recanalize in-stent chronic total occlusions.

OBJECTIVES: To evaluate the outcomes of subadventitial stenting (SS) around occluded stents for recanalizing in-stent chronic total occlusions (IS-CTOs). BACKGROUND: There is little evidence on the outcomes of SS for IS-CTO. METHODS: We examined the outcomes of SS for IS-CTO PCI at 14 centers between July 2011 and June 2017, and compared them to historical controls recanalized using within-stent stenting (WSS). Target-vessel failure (TVF) on follow-up was the endpoint of this study, and was defined as a composite of cardiac death, target-vessel myocardial infarction, and target-vessel revascularization. RESULTS: During study period, 422 IS-CTO PCIs were performed, of which 32 (7.6%) were recanalized with SS, usually when conventional approaches failed. The most frequent CTO vessel was the right coronary artery (72%). Mean J-CTO score was 3.1 ± 0.9. SS was antegrade in 53%, and retrograde in 47%. Part of the occluded stent was crushed in 37%, while the whole stent was crushed in 63%. Intravascular imaging was used in 59%. One patient (3.1%) suffered tamponade. Angiographic follow-up was performed in 10/32 patients: stents were patent in six cases, one had mild neointimal hyperplasia, and three had severe restenosis at the SS site. Clinical follow-up was available for 29/32 patients for a mean of 388 ± 303 days. The 24-month incidence of TVF was 13.8%, which was similar to historical controls treated with WSS (19.5%, P = 0.49). CONCLUSIONS: SS is rarely performed, usually as last resort, to recanalize complex IS-CTOs. It is associated with favorable acute and mid-term outcomes, but given the small sample size of our study additional research is warranted.

Update on the Management of Chronic Total Occlusions in Coronary Artery Disease.

PURPOSE OF THE REVIEW: Chronic total occlusions (CTOs) are found in about a third of patients with coronary artery disease (CAD) and can pose a significant challenge during percutaneous revascularization. However, advances in CTO percutaneous coronary intervention (PCI) strategies, devices, and algorithms have led to significant improvements in successful treatment of CTOs. This review summarizes current management of CTOs in the context of modern PCI techniques and current evidence. RECENT FINDINGS: The hybrid algorithm now provides a standardized, teachable approach to CTO PCI, and success rates are approximately 90% in experienced hands. The first randomized controlled trial in patients with CTOs recently reported that patients with ST elevation myocardial infarction (STEMI) and a CTO in the non-culprit vessel showed an improvement in ejection fraction in patients undergoing CTO PCI of the LAD, but not other vessels. Updated data from the SYNTAX trial showed a benefit with complete revascularization in patients with coronary artery disease (CAD). Incomplete revascularization of CTOs in the PCI group may explain some of the benefit seen with CABG over PCI in patients with complex coronary disease. Contemporary CTO registries have reported success rates of approximately 90%, and the OPEN-CTO registry updates our understanding of CTO PCI complication rates and outcomes. The available evidence highlights the potential benefits of CTO PCI in patients with an indication for revascularization. Technological advancements have paved the way for success rates approaching 90% at high-volume centers, but further studies evaluating outcomes following CTO PCI are needed, with several currently underway.

Cost analysis of the History, ECG, Age, Risk factors, and initial Troponin (HEART) Pathway randomized control trial.

INTRODUCTION: The HEART Pathway is a diagnostic protocol designed to identify low-risk patients presenting to the emergency department with chest pain that are safe for early discharge. This protocol has been shown to significantly decrease health care resource utilization compared with usual care. However, the impact of the HEART Pathway on the cost of care has yet to be reported. METHODS AND RESULTS: We performed a cost analysis of patients enrolled in the HEART Pathway trial, which randomized participants to either usual care or the HEART Pathway protocol. For low-risk patients, the HEART Pathway recommended early discharge from the emergency department without further testing. We compared index visit cost, cost at 30 days, and cardiac-related health care cost at 30 days between the 2 treatment arms. Costs for each patient included facility and professional costs. Cost at 30 days included total inpatient and outpatient costs, including the index encounter, regardless of etiology. Cardiac-related health care cost at 30 days included the index encounter and costs adjudicated to be cardiac-related within that period. Two hundred seventy of the 282 patients enrolled in the trial had cost data available for analysis. There was a significant reduction in cost for the HEART Pathway group at 30 days (median cost savings of $216 per individual), which was most evident in low-risk (Thrombolysis In Myocardial Infarction score of 0-1) patients (median savings of $253 per patient) and driven primarily by lower cardiac diagnostic costs in the HEART Pathway group. CONCLUSIONS: Using the HEART Pathway as a decision aid for patients with undifferentiated chest pain resulted in significant cost savings.

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.

Intravascular Imaging During Percutaneous Coronary Intervention: JACC State-of-the-Art Review.

Coronary angiography has historically served as the gold standard for diagnosis of coronary artery disease and guidance of percutaneous coronary intervention (PCI). Adjunctive use of contemporary intravascular imaging (IVI) technologies has emerged as a complement to conventional angiography-to further characterize plaque morphology and optimize the performance of PCI. IVI has utility for preintervention lesion and vessel assessment, periprocedural guidance of lesion preparation and stent deployment, and postintervention assessment of optimal endpoints and exclusion of complications. The role of IVI in reducing major adverse cardiac events in complex lesion subsets is emerging, and further studies evaluating broader use are underway or in development. This paper provides an overview of currently available IVI technologies, reviews data supporting their utilization for PCI guidance and optimization across a variety of lesion subsets, proposes best practices, and advocates for broader use of these technologies as a part of contemporary practice.

Impact of Calcium Eccentricity on the Safety and Effectiveness of Coronary Intravascular Lithotripsy: Pooled Analysis From the Disrupt CAD Studies.

BACKGROUND: Coronary intravascular lithotripsy (IVL) safely facilitates successful stent implantation in severely calcified lesions. This analysis sought to determine the relative impact of lesion calcium eccentricity on the safety and effectiveness of IVL using high-resolution optical coherence tomography imaging. METHODS: Individual patient-level data (n=262) were pooled from 4 distinct international prospective studies (Disrupt CAD I, II, III, and IV) and analyzed by an independent optical coherence tomography core laboratory. IVL performance in eccentric versus concentric calcification was analyzed by dividing calcified lesions into quartiles (≤180° [most eccentric], 181°-270°, 271°-359°, and 360° [concentric]) by maximum continuous calcium arc. RESULTS: In the 230 patients with clear imaging field on optical coherence tomography, there were no differences in preprocedure minimum lumen area, diameter stenosis, or maximum calcium thickness. The calcium length and volume index increased progressively with increasing mean and maximum continuous calcium arc (ie, concentricity). Conversely, the minimum calcium thickness decreased progressively with increasing concentricity. Post-procedure, the number of calcium fractures, fracture depth, and fracture width increased with increasing concentricity, with a 4-fold increase in the number of fractures in lesions with 360° of calcium arc compared with ≤180°. This increase in IVL-induced calcium fracture with increasing calcium burden and concentricity facilitated stent expansion and luminal gain such that there were no significant differences across quartiles. CONCLUSIONS: IVL induced calcium fractures proportional to the magnitude of coronary artery calcium, including in eccentric calcium, leading to consistent improvements in stent expansion and luminal gain in both eccentric and concentric calcified coronary lesions.