The role of intravascular imaging in chronic total occlusion percutaneous coronary intervention.

Chronic total occlusions (CTOs) represent the most complex subset of coronary artery disease and therefore careful planning of CTO percutaneous coronary recanalization (PCI) strategy is of paramount importance aiming to achieve procedural success, and improve patient's safety and post CTO PCI outcomes. Intravascular imaging has an essential role in facilitating CTO PCΙ. First, intravascular ultrasound (IVUS), due to its higher penetration depth compared to optical coherence tomography (OCT), and the additional capacity of real-time imaging without need for contrast injection is considered the preferred imaging modality for CTO PCI. Secondly, IVUS can be used to resolve proximal cap ambiguity, facilitate wire re-entry when dissection and re-entry strategies are applied and most importantly to guide stent deployment and optimization post implantation. The role of OCT during CTO PCI is currently limited to stent sizing and optimization, however, due to its high spatial resolution, OCT is ideal for detecting stent edge dissections and strut malapposition. In this review, we describe the use of intravascular imaging for lesion crossing, plaque characterization and wire tracking, extra- or intra-plaque, and stent sizing and optimization during CTO PCI and summarize the findings of the major studies in this field.

Antegrade Dissection Re-entry for Management of Retained Microcatheter Tips During PCI for Chronic Total Occlusion: A Case Series.

Application of the hybrid algorithm for the treatment of coronary chronic total occlusions requires the operator to readily deploy complex techniques and advanced technologies to achieve successful revascularization. Patient-specific factors and limitations in torquability and material strength of low-profile equipment such as microcatheters can result in procedural complications due to device fracture. Using a mini-series of 2 cases to demonstrate the successful application of antegrade dissection re-entry techniques to overcome such challenges, we highlight procedural complexities and risk, and review prior approaches and literature.

Use of Trapping Techniques and a GooseNeck Snare to Retrieve a Fractured Balloon Catheter.

Percutaneous transluminal coronary angioplasty balloon fracture, retention, and embolization are rare complications of percutaneous coronary intervention. The incidence has historically been estimated at <0.8%, which is likely an underestimate given the increasing quantity and complexity of percutaneous procedures. We demonstrate how to avoid emergency surgery by using basic balloon trapping techniques and a snare in the more distal arterial bed.

The Impact of a Dedicated Chronic Total Occlusion PCI Program on Heart Team Decision Making.

BACKGROUND: Guidelines endorse a heart team (HT) approach to standardize the decision-making process for patients with complex coronary artery disease (CAD). With percutaneous treatment options for complex CAD increasing, we hypothesized that practice had changed over the past decade-and that more individuals, previously deemed too high risk for intervention, would now be referred for either surgical or percutaneous revascularization. METHODS: This observational study was conducted at St Thomas' Hospital (London, United Kingdom). All patients discussed at HT meetings were recorded and treatment recommendations audited. A subset of historic cases was selected for blinded, repeat discussion. RESULTS: From April 2018 to 2019, a total of 52 HT meetings discussing 375 cases were held. Patients tended to be male, with a majority demonstrating multivessel CAD in the context of preserved left ventricular function. SYNTAX scores were balanced across the tertiles. Thirty-five percent of patients had at least 1 chronic total occlusion (mean J-CTO, 3 [interquartile range, 2-3]), affecting the right coronary artery in 60%. Fifteen historic patients with isolated CTOs were re-presented an average of 8 years later; only 3 patients received the same outcome, with 80% now receiving a recommendation for revascularization over medical therapy. CONCLUSIONS: A dedicated program supporting complex coronary intervention is associated with a change in treatment recommendations issued by the local HT. In line with international guidelines, this might indicate that any complex or multivessel CAD should be discussed at HT meetings with, ideally, the presence of CTO operators.

Sodium-glucose co-transporter 2 inhibitors in COVID-19: meeting at the crossroads between heart, diabetes and infectious diseases.

Sodium-glucose co-transporter 2 inhibitors (SGLT2i) are a new class of glucose-lowering agents which have changed the landscape of diabetes therapy, due to their remarkable cardiorenal protective properties. The attack of severe acute respiratory syndrome coronavirus 2 on the heart and kidneys shares similarities with diabetes; therefore, the notion that SGLT2i might have a role in the future management of Coronavirus Disease 2019 (COVID-19) is based on a solid pathophysiological hypothesis. SGLT2i have been proved to decrease the expression of proinflammatory cytokines, ameliorate oxidative stress and reduce sympathetic activity, thus resulting in downregulation of both systemic and adipose tissue inflammation. On the other hand, they have been linked to an increased risk of euglycemic diabetic ketoacidosis. Therefore, the efficacy and safety of SGLT2i in COVID-19 are still debatable and remain to be clarified by ongoing randomized trials, to assess whether the benefits of treatment with these drugs outweigh the potential risks.

Impact and Determinants of High-Sensitivity Cardiac Troponin-T Concentration in Patients With COVID-19 Admitted to Critical Care.

Cardiac Troponin (hs-TnT) elevation has been reported in unselected patients hospitalized with COVID-19 however the mechanism and relationship with mortality remain unclear. Consecutive patients admitted to a high-volume intensive care unit (ICU) in London with severe COVID-19 pneumonitis were included if hs-TnT concentration at admission was known. Kaplan-Meier survival analysis performed, with cohorts classified a priori by multiples of the upper limit of normal (ULN). 277 patients were admitted during a 7-week period in 2020; 176 were included (90% received invasive ventilation). hs-TnT at admission was 16.5 (9.0 to 49.3) ng/L, 56% had concentrations >ULN. 56 patients (31.8%) died during the index admission. Admission hs-TnT level was lower in survivors (12.0 (8.0-27.8) vs 28.5 (14.0 to 81.0) ng/L, p = 0.001). Univariate predictors of mortality were age, APACHE-II Score and admission hs-TnT (HR 1.73, p = 0.007). By multivariate regression, only age (HR 1.33, CI: 1.16.to 1.51, p < 0.01) and admission hs-TnT (HR 1.94, CI: 1.22 to 3.10, p = 0.006) remained predictive. Survival was significantly lower when admission hs-TnT was >ULN (log-rank p-value<0.001). Peak hs-TnT was higher in those who died but was not predictive of death after adjustment for other factors. In conclusion, in critically ill patients with COVID-19 pneumonitis, the hs-TnT level at admission is a powerful independent predictor of the likelihood of surviving to discharge from ICU. In most cases, hs-TnT elevation does not represent major myocardial injury but acts as a sensitive integrated biomarker of global stress. Whether stratification based on admission Troponin level could be used to guide prognostication and management warrants further evaluation.

PCSK9 Inhibitors for the Management of Dyslipidemia in People with Type 2 Diabetes: How Low is Too Low?

Diabetic patients are considered to be at high risk for the development of atherosclerotic disease. Management of hypercholesterolemia is of paramount importance to optimize cardiovascular outcomes in this subset of patients and statins are regarded as the mainstay of treatment. However, the recent advent of PCSK-9 inhibitors has provided a useful alternative in the management of dyslipidemia, especially when statins cannot be tolerated or when hypolipidemic targets cannot be achieved. In this review, we discuss current trends in their use, and we focus on their role in the management of diabetic dyslipidemia.

Guide-Extension Facilitated Antegrade Dissection Re-entry: A Case Series.

Treatment of chronic total occlusions poses a specific set of challenges above and beyond those encountered in conventional percutaneous coronary intervention. Antegrade dissection and re-entry (ADR) is an established and safe technique with high success rates in experienced centers. CTO techniques frequently require greater-than-usual guide-catheter support and rapid-exchange technologies. Either can be achieved with separate guide extension and a trapping balloon; in this case series of guide-extension facilitated ADR, we highlight the technical advantages gleaned from the use of combined devices such as the TrapLiner guide-extension catheter (Teleflex).

Long-Term Outcomes Following Heart Team Revascularization Recommendations in Complex Coronary Artery Disease.

Background The Heart Team ( HT ) comprises integrated interdisciplinary decision making. Current guidelines assign a Class Ic recommendation for an HT approach to complex coronary artery disease ( CAD ). However, there remains a paucity of data in regard to hard clinical end points. The aim was to determine characteristics and outcomes in patients with complex CAD following HT discussion. Methods and Results This observational study was conducted at St Thomas' Hospital (London, UK). Case mixture included unprotected left main, 2-vessel (including proximal left anterior descending artery) CAD , 3-vessel CAD , or anatomical and/or clinical equipoise. HT strategy was defined as optimal medical therapy ( OMT ) alone, OMT +percutaneous coronary intervention ( PCI ), or OMT +coronary artery bypass grafting. From April 2012 to 2013, 51 HT meetings were held and 398 cases were discussed. Patients tended to have multivessel CAD (74.1%), high SYNTAX (Synergy between PCI with Taxus and Cardiac Surgery) scores (median, 30; interquartile range, 23-39), and average age 69±11 years. Multinomial logistic regression analysis performed to determine variables associated with HT strategy demonstrated decreased likelihood of undergoing PCI compared with OMT in older patients with chronic kidney disease and peripheral vascular disease. The odds of undergoing coronary artery bypass grafting compared with OMT decreased in the presence of cardiogenic shock and left ventricular dysfunction and increased in younger patients with 3-vessel CAD . Three-year survival was 60.8% (84 of 137) in the OMT cohort, 84.3% (107 of 127) in the OMT + PCI cohort, and 90.2% in the OMT +coronary artery bypass grafting cohort (92 of 102). Conclusions In our experience, the HT approach involved a careful selection process resulting in appropriate patient-specific decision making and good long-term outcomes in patients with complex CAD .

Spinal Hematoma Following Coronary Angioplasty: An Uncommon Complication.

We report an unusual case of post-procedural spontaneous spinal epidural hematoma in a 65 year old man who presented with an acute coronary syndrome and underwent complex coronary intervention with adjunct use of a GPIIb/IIIa inhibitor. Although spontaneous spinal epidural hematoma (SSEH) following coronary intervention is extremely rare, clinicians should be aware of this unusual diagnosis. Prompt investigation with MRI and early referral for neurosurgical input are recommended to prevent potentially significant sequelae.

Stronger correlation with myocardial ischemia of high-sensitivity troponin T than other biomarkers.

BACKGROUND: Acute myocardial infarction (AMI) is considered a major cause of death and disability. Myocardial perfusion scintigraphy (MPS) as a non-invasive diagnostic imaging procedure and certain biomarkers associated with myocardial ischemia (ISCH), such as ischemia-modified albumin (IMA), neuropeptide Y (NPY), N-terminal pro b-type natriuretic peptide (NT-proBNP), and high-sensitivity troponin T (hsTnT) could probably aid in the detection of myocardial infarction. METHODS: Between December 2011 and June 2012, we prospectively analyzed patients who underwent a MPS study with the clinical question of myocardial ISCH. An exercise test was performed along with a MPS. Blood was drawn from the patients before exercise and the within 3 minutes from achieving maximum load and was analyzed for the aforementioned biomarkers. RESULTS: A total of 71 patients (56 men and 15 women) were enrolled with a mean age of 61 ± 12 years. Twenty-six patients (36.6%) showed reduced uptake on stress MPS images that normalized at rest, a finding consistent with ISCH. Between ISCH and non-ISCH groups, only hsTnT levels showed a significant difference with the highest levels pertaining to the former group both before (0.0075 ng/ml vs 0.0050 ng/ml, P = 0.023) and after stress exercise (0.0085 vs 0.0050, P = 0.015). The most prominent differences were seen in higher stages of the Bruce protocol (stress duration > 9.05 minutes - P < 0.017). None of the IMA, NPY, and NP-pro BNP showed significant differences in time between the two groups. CONCLUSIONS: Although IMA, NPY, and NT-pro BNP may not detect minor ischemic myocardial insults, serum hsTnT holds a greater ability of detecting not only myocardial infarction but also less severe ischemia. Further studies with larger cohorts of patients are warranted in order to better define the role of hsTnT as a screening tool for myocardial ischemia.

Outcomes after chronic total occlusion percutaneous coronary interventions: an observational study of 5496 patients from the Pan-London CTO Cohort.

BACKGROUND: Chronic total occlusions (CTO) are commonly encountered in patients undergoing coronary angiography; however, percutaneous coronary intervention (PCI) is infrequently performed owing to technical difficulty, the perceived risk of complications and a lack of randomized data. The aim of this study was to analyse the frequency and outcomes of CTO-PCI procedures in a large contemporary cohort of successive patients. PATIENTS AND METHODS: We undertook an observational cohort study of 48 234 patients with stable angina of which 5496 (11.4%) procedures were performed for CTOs between 2005 and 2015 at nine tertiary cardiac centres across London, UK. Outcome was assessed by in-hospital major adverse cardiac events and all-cause mortality at a median follow-up of 4.8 years (interquartile range: 2.2-6.4 years). RESULTS: Over time, there was an increase in the proportion of elective PCI procedures performed for CTOs, but no increase in the absolute number. Overall success rates increased over time (74.3% in 2005 to 81.5% in 2015; P=0.0003) despite an increase in case complexity (previous myocardial infarction, diabetes, renal failure, previous coronary artery bypass grafting, peripheral vascular disease and left ventricular impairment) that correlated with procedural advancements. Successful CTO PCI was associated with lower mortality [9.5%, 95% confidence interval (CI): 8.1-11.6 vs. 15.3%, 95% CI: 13.7-20.6, P<0.0001] that persisted after multivariate cox analysis (hazard ratio: 0.37, 95% CI: 0.25-0.62) and propensity matching (hazard ratio=0.36, 95% CI: 0.18-0.73, P=0.0005). CONCLUSION: Successful procedures were associated with lower mortality suggesting that the greater uptake of CTO PCI may improve clinical outcomes in a wider population than are currently being offered therapy.

Balloon-assisted tracking: A practical solution to avoid radial access failure due to difficult anatomical challenges.

AIM: The balloon assisted tracking (BAT) technique is utilised to overcome various anatomical difficulties during radial procedures when standard measures such as adequate sedation, pain relief, vasodilators and use of hydrophilic guidewires, fail. The aim of this study was to evaluate the success rates of the BAT technique in overcoming anatomical difficulties during radial coronary interventional procedures. METHODS: We retrospectively reviewed 1100 consecutive patients undergoing coronary procedures from the transradial approach (TRA) between May 2015 and May 2017. Anatomic variations and equipment used were recorded from procedure logs. RESULTS: Overall 30 patients (2.72%) required the use of BAT. Mean age was 66.7years, with a range from 48 to 90years (53.3% female). Out of these 30 cases, 86.7% patients underwent percutaneous coronary intervention (PCI) while the remaining patients underwent coronary angiography alone. Acute coronary syndrome cases represented 63.3% of the cases while the remaining patients were elective procedures. Anatomical difficulties included severe, non-resolving radial spasm (66.6%), catheter induced radial or brachial perforation (16.6%), small calibre and/or diseased radial artery (10.0%), severe radial, branchial and/or subclavian tortuosity (3.0%) and radial loops (3.0%). Anatomical difficulties were overcome in all cases (100%). Coronary angiography and/or PCI were successfully completed in all 30 cases without the need for obtaining alternative arterial access. Mean added procedural time was 131s. There were no procedure related complications. CONCLUSION: Balloon assisted tracking is a highly successful and safe technique for overcoming various anatomical difficulties at the level of the radial, brachial or subclavian arteries, which minimises the need for alternative arterial access.

When everything else fails: High-pressure balloon for undilatable lesions.

Heavily calcified lesions are encountered with increasing frequency during percutaneous coronary interventions (PCI). This poses a significant problem as it often leads to suboptimal stent expansion, which in turn is a major cause for stent restenosis and thrombosis. Various technologies have been developed to tackle this. The high-pressure balloon (OPN) seems to be a promising adjunct in treating undilatable lesions. In this concise mini review we highlight the use of HPB and we present the current status of technology implemented in complex PCI cases.

Implementation and consistency of Heart Team decision-making in complex coronary revascularisation.

BACKGROUND: A multidisciplinary team (MDT) approach for decision-making in patients with complex coronary artery disease (CAD) is now a class IC recommendation in the European and American guidelines for myocardial revascularisation. The aim of this study was to evaluate the implementation and consistency of Heart Team HT decision-making in complex coronary revascularisation. METHODS: We prospectively evaluated the data of 399 patients derived from 51 consecutive MDT meetings held in a tertiary cardiac centre. A subset of cases was randomly selected and re-presented with the same clinical data to a panel blinded to the initial outcome, at least 6 months after the initial discussion, in order to evaluate the reproducibility of decision-making. RESULTS: The most common decisions included continued medical management (30%), coronary artery bypass grafting (CABG) (26%) and percutaneous coronary intervention (PCI) (17%). Other decisions, such as further assessment of symptoms or evaluation with further invasive or non-invasive tests were made in 25% of the cases. Decisions were implemented in 93% of the cases. On re-discussion of the same data (n=40) within a median period of 9 months 80% of the initial HT recommendations were successfully reproduced. CONCLUSIONS: The Heart Team is a robust process in the management of patient with complex CAD and decisions are largely reproducible. Although outcomes are successfully implemented in the majority of the cases, it is important that all clinical information is available during discussion and patient preference is taken into account.

Reducing radiation in chronic total occlusion percutaneous coronary interventions.

The field of percutaneous intervention for chronic total occlusion (CTO) has enjoyed significant innovations in the recent years. Novel techniques and technologies have revolutionized the field and have resulted in considerably higher success rates even in patients with high anatomical complexity. Successful CTO recanalization is associated with significant clinical benefits, such as the improvement of angina and quality of life, reduced rates of surgical revascularization, improvement of left ventricular function and decreased mortality rates. However, complex CTO procedures often require prolonged x-ray exposure which have been associated with adverse long term outcomes.

Prevention of contrast-induced acute kidney injury after percutaneous coronary intervention for chronic total coronary occlusions.

Chronic total occlusions (CTOs) represent a major challenge in percutaneous coronary revascularization. The recent advances in strategies and techniques and the development of dedicated equipment, such as microcatheters and wires, have resulted in considerably higher success rates. Although successful CTO recanalization is associated with significant clinical benefits, including improvement of angina, quality of life, reduced need for surgical revascularization, and improvement of left ventricular function, CTO procedures may require prolonged x-ray exposure and use of larger volumes of contrast compared with non-CTO procedures. Large volumes of contrast medium have been associated with increased rates of contrast-induced acute kidney injury (CI-AKI) and adverse short- and long-term outcomes. Application of specific measures and algorithms should be considered by all CTO operators to prevent CI-AKI.