Barriers and facilitators to interhospital transfer of acute pulmonary embolism: An inductive qualitative analysis.

Background: Interhospital transfer (IHT) of patients with acute life-threatening pulmonary embolism (PE) is necessary to facilitate specialized care and access to advanced therapies. Our goal was to understand what barriers and facilitators may exist during this transfer process from the perspective of both receiving and referring physicians. Methods: This qualitative descriptive study explored physician experience taking care of patients with life threatening PE. Subject matter expert physicians across several different specialties from academic and community United States hospitals participated in qualitative semi-structured interviews. Interview transcripts were subsequently analyzed using inductive qualitative description approach. Results: Four major themes were identified as barriers that impede IHT among patients with life threatening PE. Inefficient communication which mainly pertained to difficulty when multiple points of contact were required to complete a transfer. Subjectivity in the indication for transfer which highlighted the importance of physicians understanding how to use standardized risk stratification tools and to properly triage these patients. Delays in data acquisition were identified in regards to both obtaining clinical information and imaging in a timely fashion. Operation barriers which included difficulty finding available beds for transfer and poor weather conditions inhibiting transportation. In contrast, two main facilitators to transfer were identified: good communication and reliance on colleagues and dedicated team for transferring and treating PE patients. Conclusion: The most prominent themes identified as barriers to IHT for patients with acute life-threatening PE were: (1) inefficient communication, (2) subjectivity in the indication for transfer, (3) delays in data acquisition (imaging or clinical), and (4) operational barriers. Themes identified as facilitators that enable the transfer of patients were: (1) good communication and (2) a dedicated transfer team. The themes presented in our study are useful in identifying opportunities to optimize the IHT of patients with acute PE and improve patient care. These opportunities include instituting educational programs, streamlining the transfer process, and formulating a consensus statement to serve as a guideline regarding IHT of patients with acute PE.

Technological Advances in Stent Therapies: a Year in Review.

Stent technology has rapidly evolved since the first stainless steel bare metal stents with substantial developments in scaffolding, polymer, drug choice, drug delivery, and elution mechanisms. Most recently, there has been the evolution of bioabsorbable vascular scaffolds, potentially eliminating the need for long-term foreign object retention. These rapid developments have led to an ever-expanding selection of new stents, making the choice of which to use in which patient challenging. Operators must balance potential short- and long-term clinical ramifications, namely stent thrombosis, in-stent restenosis, target lesion revascularization, and target lesion failure. In this review, we hope to provide insight for interventional cardiologists on the details of stent technology and how this impacts outcomes, stent selection, and duration of dual-antiplatelet therapy duration post drug-eluting stent implantation.

Antithrombotic Selection in ST-Segment Elevation Myocardial Infarction: a Year in Review.

OPINION STATEMENT: In ST-segment elevation myocardial infarction (STEMI), interventional cardiologists must move quickly to safely re-establish blood flow while choosing an antithrombotic to preclude wire thrombosis, aid in the restoration of flow, minimize thrombus propagation, and reduce the risk of stent thrombosis. Currently, operators have a choice between heparin and bivalirudin with the possible addition of glycoprotein IIb/IIIa inhibitors (GPIs). Prior studies have shown that bivalirudin use lowers rates of bleeding, but with a clear risk of acute stent thrombosis. Recent studies have examined this question in the modern era of radial access and newer antiplatelet agents. Despite these studies, there remains a question regarding which antithrombotic agent is to be selected in STEMI.

Cardiovascular mortality prediction in veterans with arm exercise vs pharmacologic myocardial perfusion imaging.

BACKGROUND: No data exist comparing outcome prediction from arm exercise vs pharmacologic myocardial perfusion imaging (MPI) stress test variables in patients unable to perform treadmill exercise. METHODS: In this retrospective study, 2,173 consecutive lower extremity disabled veterans aged 65.4 ± 11.0years (mean ± SD) underwent either pharmacologic MPI (1730 patients) or arm exercise stress tests (443 patients) with MPI (n = 253) or electrocardiography alone (n = 190) between 1997 and 2002. Cox multivariate regression models and reclassification analysis by integrated discrimination improvement (IDI) were used to characterize stress test and MPI predictors of cardiovascular mortality at ≥10-year follow-up after inclusion of significant demographic, clinical, and other variables. RESULTS: Cardiovascular death occurred in 561 pharmacologic MPI and 102 arm exercise participants. Multivariate-adjusted cardiovascular mortality was predicted by arm exercise resting metabolic equivalents (hazard ratio [HR] 0.52, 95% CI 0.39-0.69, P < .001), 1-minute heart rate recovery (HR 0.61, 95% CI 0.44-0.86, P < .001), and pharmacologic and arm exercise delta (peak-rest) heart rate (both P < .001). Only an abnormal arm exercise MPI prognosticated cardiovascular death by multivariate Cox analysis (HR 1.98, 95% CI 1.04-3.77, P < .05). Arm exercise MPI defect number, type, and size provided IDI over covariates for prediction of cardiovascular mortality (IDI = 0.074-0.097). Only pharmacologic defect size prognosticated cardiovascular mortality (IDI = 0.022). CONCLUSIONS: Arm exercise capacity, heart rate recovery, and pharmacologic and arm exercise heart rate responses are robust predictors of cardiovascular mortality. Arm exercise MPI results are equivalent and possibly superior to pharmacologic MPI for cardiovascular mortality prediction in patients unable to perform treadmill exercise.

The path of least resistance to success in chronic hypertension?

The ROX Coupler is a stented arterial-venous anastomosis intended for implantation in the external iliac artery and vein. Prior studies of the ROX Coupler show that it increases cardiac output, oxygen delivery, and decreases systemic vascular resistance, thereby lowering blood pressure. Clinical data for the ROX Coupler demonstrates significant reduction in blood pressure but proximal venous stenoses have been seen post-implantation requiring treatment.

Dual antiplatelet therapy duration after the placement of a drug-eluting stent: what are the data?

OPINION STATEMENT: The data supporting the immediate use of dual antiplatelet therapy (DAPT) post implantation of drug-eluting stents (DESs) is irrefutable. DAPT in this early period is necessary to prevent stent thrombosis during endothelialization of the stent, a process known to be delayed when DESs are placed. In addition, DAPT helps prevent thrombosis from plaque rupture that occurs outside of the initial stented area and/or at neo-atherosclerotic lesions within a previously coated stent. The ACC/AHA current guidelines (Levine et al. J Am Coll Cardiol. 58(24):e44-122, 2011) recommend 12 months of DAPT post DES implantation. As the result of several randomized clinical trials (Task Force on Myocardial Revascularization of the European Society of Cardio-Thoracic Surgery (EACTS) et al. Eur Heart J. 31(20):2501-55, 2010) showing the safety of a shorter duration of DAPT, the European Heart Society altered their recommendations to 6-12 months of DAPT post DES implantation. However, recent data from the DAPT trial (Mauri et al. N Engl J Med. 371(23):2156-66, 2014) clearly demonstrated less ischemic events with 30 months of DAPT. This trial and others have established that an increased DAPT duration increases bleeding risk which, in turn, increases subsequent morbidity and mortality. The current conundrum lies in defining the optimal time of DAPT post DES to adequately reduce ischemic events while minimizing bleeding risks. Future studies are required to better stratify patients into low and high risk for both ischemic and bleeding risks to assess whether shorter or longer courses of DAPT are the most appropriate for any specific patients. Until then, instead of a "one size fits all" approach to patients who receive DESs, the treating physician must consider both procedural and patient factors when deciding the optimal duration of DAPT for each patient.

Anomalous left circumflex artery from the right coronary cusp: a benign variant?

OBJECTIVE: To determine the incidence of angiographically evident coronary artery disease (CAD) of the anomalous left circumflex artery (ALCx). BACKGROUND: Due to the acute angulation of its origin from the aorta and its retroaortic course, some have proposed an increase in CAD in these vessels. METHODS: We performed a retrospective cohort study of all patients (n = 5205) presenting for left heart catheterization at the St Louis Veterans Affairs hospital from 2006-2012. Quantitative coronary angiography (QCA) was performed by two independent operators for all cases identified as having ALCx (n = 18). RESULTS: We identified 18 patients (0.346%) with this anomaly. Sixteen of 18 cases (89%) had atherosclerosis involving the ALCx. QCA performed on the ALCx for all 18 patients resulted in a mean stenosis of 61% (range, 10%-100%). Seven out of 18 patients (39%) had obstructive CAD of the ALCx with the majority (n = 6; 86%) also having concomitant obstructive disease in the left anterior descending (LAD) or right coronary artery (RCA). In the 5 cases where the ALCx underwent intervention, the mean diameter stent was 2.25 mm, with a mean length of 15 mm, indicating that these vessels were small in caliber with focal disease. At a mean follow-up of 18 months for all patients, there was 1 non-cardiac death in the non-intervened group, with the 17 remaining patients (94.7%) free of major adverse cardiovascular events (target lesion revascularization, target vessel revascularization, or death). CONCLUSIONS: This study suggests that indeed this most common anomaly appears to be benign in that its unique origin and/or retroaortic course do not increase the occurrence of atherosclerosis relative to the LAD and RCA.

Pre-procedural planning for percutaneous atrial septal defect closure: transesophageal echocardiography compared with cardiac computed tomographic angiography.

BACKGROUND: The safety and efficacy of percutaneous closure of atrial septal defects (ASDs) is determined by several variables, including defect size, presence of adequate rim tissue, relationship to other cardiac structures, and associated congenital anomalies. OBJECTIVE: We sought to determine the accuracy of computed tomographic angiography (CTA) in predicting a defect's size compared with pre-procedural transesophageal echocardiography (TEE) and to the current "gold standard" balloon sizing by intracardiac echocardiography (ICE). METHODS: Thirty-five consecutive patients referred for possible percutaneous closure of suspected secundum ASD were evaluated with gated multislice CTA after initial TEE screening. Axial and sagittal image planes of the ASD from the CTA multiplanar reformation (MPR) images were used to measure the defect size and surface area. RESULTS: Of the 35 patients with secundum-type ASDs, 5 subjects had disqualifying anatomy by CTA and 2 had an unsuccessful closure, resulting in a procedural success rate of 93%. Measurement of defect area by gated MPR images provided the strongest correlate to ICE balloon size. In large ASDs, TEE was less well correlated to the maximum defect size and identification of the inferior/inferoposterior rims than CTA. CONCLUSIONS: Cardiac CTA is an accurate and useful technique for pre-procedural assessment of ASDs and may be superior to conventional TEE in large defects that have deficient inferior rims.

Clinical feasibility of a fully automated 3D reconstruction of rotational coronary X-ray angiograms.

BACKGROUND: Although fixed view x-ray angiography remains the primary technique for anatomic imaging of coronary artery disease, the known shortcomings of 2D projection imaging may limit accurate 3D vessel and lesion definition and characterization. A recently developed method to create 3D images of the coronary arteries uses x-ray projection images acquired during a 180 degrees C-arm rotation and continuous contrast injection followed by ECG-gated iterative reconstruction. This method shows promise for providing high-quality 3D reconstructions of the coronary arteries with no user interaction but requires clinical evaluation. METHODS AND RESULTS: The reconstruction strategy was evaluated by comparing the reconstructed 3D volumetric images with the 2D angiographic projection images from the same 23 patients to ascertain overall image quality, lesion visibility, and a comparison of 3D quantitative coronary analysis with 2D quantitative coronary analysis. The majority of the resulting 3D volume images were rated as having high image quality (66%) and provided the physician with additional clinical information such as complete visualization of bifurcations and unobtainable views of the coronary tree. True-positive lesion detection rates were high (90 to 100%), whereas false-positive detection rates were low (0 to 8.1%). Finally, 3D quantitative coronary analysis showed significant similarity with 2D quantitative coronary analysis in terms of lumen diameters and provided vessel segment length free from the errors of foreshortening. CONCLUSIONS: Fully automated reconstruction of rotational coronary x-ray angiograms is feasible, produces 3D volumetric images that overcome some of the limitations of standard 2D angiography, and is ready for further implementation and study in the clinical environment.

Rotational coronary angiography.

The numerous well-documented limitations of standard fixed-acquisition coronary angiography led to the development of rotational angiography. This acquisition method uses automated gantry movements while numerous angiographic projections are obtained, and thus overcomes many of the limitations of standard angiography. This article highlights the techniques, advantages, and disadvantages of each type of rotational angiography currently commercially available. Also included is a discussion of the evolution of rotational angiography, from its initial conception and pilot studies to its latest step forward on the developmental road towards enhanced coronary imaging.