Histopathologic Characterization of Chronic Total Occlusions by Directional Atherectomy: The HIPACT Study.

BACKGROUND: Chronic total occlusions (CTOs) and long lesions have been associated with higher reocclusion rates in femoropopliteal arteries and increased need for revascularization. While several studies have analyzed atherectomy samples, no study to date has correlated the tissue characteristics of CTOs with clinical outcomes. This pilot study assessed lesions in order to predict clinical outcomes based on lesion characteristics. METHODS: Patients presenting with femoropopliteal (FP) CTO lesions, including in-stent restenosis and de novo lesions, were enrolled in a prospective, observational study. With patient consent, CTOs were crossed using a crossing catheter guided by optical coherence tomography (OCT) imaging. Atherectomy was performed with a directional atherectomy device and tissue samples were collected and subjected to histopathological analysis for the presence of adventitial tissue and thrombus, and the amounts of hypercellular cells, fibrocellular material, fibrous tissue, and lipid-rich tissue in the excised tissue were measured. The compiled data were correlated with clinical outcomes, as recorded at each patient's clinical follow-up visit. RESULTS: All CTO lesions (n = 19) were successfully crossed, with no dissections or perforations. Adventitial tissue was found in excised tissue from all 19 lesions (up to 57% of total lesion area), and thrombus was found in 15 lesions (up to 34% of total lesion area). The amount of hypercellular cells, fibrocellular material, fibrous tissue, and lipid-rich tissue present in the excised tissue did not correlate with the incidence of target-lesion revascularization (TLR). At 6-month follow-up exam, 79% of the treated lesions had TLR. Risk of TLR was assessed based on weighted risk of each variable; the results determined that occurrence of TLR was associated with elevated levels of adventitia and thrombus in the lesions and with lesions >15 cm in length. There was a significant correlation (P<.05) between TLR and the lesion characterization as set forth in the present study. CONCLUSIONS: Pairing the histological analysis, including content of adventitia and thrombus, with lesion length and binary clinical outcomes enabled the predictive incidence of TLR in this pilot study. Further work needs to be conducted to validate these findings in larger studies.

Facilitated Intravascular Ultrasound-Guided Balloon-Assisted Re-Entry Technique for Complex Lower-Extremity Chronic Total Occlusions: The FIBRE Technique.

PURPOSE: To examine the efficacy and safety of the facilitated intravascular ultrasound (IVUS)-guided balloon assisted-re-entry (FIBRE) technique in the treatment of complex, chronic total occlusion (CTO) peripheral arterial lesions. METHODS: A retrospective analysis of 150 patients undergoing peripheral intervention for lower extremity CTO was performed from 2014 to 2017 at two institutions. From the selected population, 10 patients with complex CTOs were identified using the FIBRE technique. Procedural success, 30 day and 6 month patency rates, ankle brachial index improvement, and complications were analyzed. RESULTS: Ten out of 150 patients had the FIBRE technique utilized to attempt revascularization of a complex CTO of a femoropopliteal artery. Technical success was achieved in all 10 patients (100%). There were no intra-operative or peri-procedural complications reported including vessel perforation, bleeding, distal embolization, infrapopliteal vessel compromise, or infection. Arterial studies were obtained at 30 days and 6 months to assess patency in 9/10 patients (90%), with 1 patient being lost to follow up. Of the 9 patients, all 9 (100%) had documented arterial patency at both 30 days and 6 months. All patients reported improvement in symptoms. There were also no reports of re-intervention, amputation, or death at 6-month follow up. CONCLUSIONS: The FIBRE technique is a safe and feasible strategy with excellent technical success in experienced hands for revascularization of complex lower extremity CTO when conventional modalities fail.

Predictors of reduced cardiac index in patients with acute submassive pulmonary embolism.

OBJECTIVES: Determine the baseline clinical, laboratory, and echocardiographic values that predict reduced cardiac index (CI) among subjects with acute submassive pulmonary embolism (PE). BACKGROUND: Submassive PE represents a large portion of acute PE population and there is controversy regarding optimal treatment strategies for these patients. There is significant heterogeneity within the submassive PE population and further refinement of risk stratification may aid clinical decision-making. METHODS: We identified subjects with normotensive acute PE who underwent echocardiogram and right heart catheterization (RHC) prior to catheter-directed thrombolysis (CDT). We sought to determine the predictors of reduced CI, defined as CI < 2.2 L min-1 m-2 . RESULTS: Thirty-two subjects met the inclusion criteria and 41% had reduced CI. Baseline variables did not distinguish subjects with reduced versus normal CI. Brain natriuretic peptide (BNP) was significantly different between the reduced versus normal CI groups (BNP 440 vs. 160 pg/ml, p = .004, respectively). Univariate logistic regression identified BNP, right ventricular (RV):left ventricular (LV) diameter ratio, tricuspid annular plane systolic excursion (TAPSE), and right ventricular systolic pressure as predictors of reduced CI. In a multivariate logistic regression model, only TAPSE was an independent predictor of reduced CI. ROC curve analysis identified the following optimal cut points for prediction of reduced CI: BNP > 216 pg/ml, RV:LV ratio > 1.41, or TAPSE <1.6 cm. CONCLUSIONS: Almost half of subjects with acute submassive PE have reduced CI, despite normal systemic blood pressure. Optimal cut points for BNP, RV:LV ratio, and TAPSE were identified to predict reduced CI among patients with acute PE. These findings may aid in clinical decision-making and risk stratification of patients with acute submassive PE.

Femoral Artery Chronic Total Occlusion Revascularization (FACTOR) Score and Algorithm: Feasibility and Validation in a Single-Center Study of Femoropopliteal Occlusions.

OBJECTIVES: To develop and validate a hybrid algorithm to approach complex superficial femoral artery (SFA) chronic total occlusions (CTOs) in a step-wise fashion. BACKGROUND: SFA-CTO represents one of the most challenging subsets of lower-extremity peripheral arterial disease. Depending on lesion characteristics, successful percutaneous crossing of the occluded segment may prove to be very difficult. METHODS: We retrospectively evaluated all consecutive patients with SFA-CTO at our institution. The included patients had baseline Rutherford category (2-4) symptoms and were graded using the femoral artery chronic total occlusion revascularization (FACTOR) score. Multiple modalities (wire-based strategies, CTO devices, re-entry devices) were used to cross the occlusions based on the proposed FACTOR algorithm. Primary endpoint was technical success, defined as successful CTO crossing. RESULTS: A total of 150 patients (mean age, 71 years) with SFA-CTO were retrospectively reviewed to evaluate the feasibility and utility of the FACTOR score and algorithm in a single center across multiple experienced operators. Following the FACTOR algorithm, overall procedural success was achieved in 143 out of 150 patients (95%). Successful antegrade CTO crossing occurred in 59%; success rates increased to 85% when additional retrograde popliteal, tibiopedal, and direct SFA accesses were used. In multivariate analysis, retrograde wire crossing, stent placement, and atherectomy were independent predictors of successful revascularization. CONCLUSIONS: The results of our study show that utilization of the FACTOR score and algorithm can result in high rates of successful SFA-CTO revascularization.

Effect of hemostatic device on radial artery occlusion: A randomized comparison of compression devices in the radial hemostasis study.

BACKGROUND: Asymptomatic radial artery occlusion (RAO) is a major limitation of transradial catheterization (TRC). Two radial compression hemostatic devices are compared for their respective effects on RAO. METHODS: In a prospective, randomized, single center, blinded trial, 320 patients were randomly treated with a TR band (Terumo Corporation) or Safeguard Radial (Merit Medical). Institution wide protocols consisting of anticoagulation, patent hemostasis, duration of compression, and use of 6 French slender sheaths (Terumo Corporation) were observed. Patient discomfort related to the device was recorded using the universal pain scale. Radial artery patency was evaluated by reverse Barbeau's test prior to discharge (1-hour post-diagnostic catheterization or 6-24 hour post-intervention) and at 30-days. RESULTS: Of the 320 patients, 155 were randomized to the TR group (TRG) and 159 to the Safeguard group (SGG). 6 patients were excluded due to the inability to insert 6 Fr slender sheaths or patient withdrawing consent. Demographic and procedural characteristics were similar with the exception of the type of coronary procedure performed. Both bands were equally effective in achieving patent hemostasis. Despite having a higher rate of post-procedure hematoma (1.29% TRG vs. 3.1% SGG, p = 0.04) and acute RAO (3.8% TRG vs. 6.28% SGG, p = 0.05) with the Safeguard band, at 30 days RAO was similar in both groups (1.9% TRG vs. 2.5% SGG; p = 0.21). Patients in the SGG reported significantly less band discomfort and were found to require less air to achieve patent hemostasis. CONCLUSION: Evidence-based contemporary TRC protocols of using smaller diameter access, anticoagulation, and use of just enough pressure for the shortest duration of time to achieve hemostasis is associated with very low RAO rate at 30 days irrespective of the radial compression device used.

Diastolic Compression of the Left Anterior Descending Artery.

The patient underwent mitral valve replacement with a bioprosthetic porcine valve, tricuspid valve annuloplasty, and left atrial appendage ligation with good result and an uncomplicated postoperative course.

Randomized Comparison of a CrossBoss First Versus Standard Wire Escalation Strategy for Crossing Coronary Chronic Total Occlusions: The CrossBoss First Trial.

OBJECTIVES: The authors performed a multicenter, randomized-controlled, clinical trial comparing upfront use of the CrossBoss catheter versus antegrade wire escalation for antegrade crossing of coronary chronic total occlusions. BACKGROUND: There is equipoise about the optimal initial strategy for crossing coronary chronic total occlusions. METHODS: The primary endpoints were the time required to cross the chronic total occlusion or abort the procedure and the frequency of procedural major adverse cardiovascular events. The secondary endpoints were technical and procedural success, total procedure time, fluoroscopy time required to cross and total fluoroscopy time, total air kerma radiation dose, total contrast volume, and equipment use. RESULTS: Between 2015 and 2017, 246 patients were randomized to the CrossBoss catheter (n = 122) or wire escalation (n = 124) at 11 U.S. centers. The baseline clinical and angiographic characteristics of the study groups were similar. Technical and procedural success were 87.8% and 84.1%, respectively, and were similar in the 2 groups. Crossing time was similar: 56 min (interquartile range: 33 to 93 min) in the CrossBoss group and 66 min (interquartile range: 36 to 105 min) in the wire escalation group (p = 0.323), as was as the incidence of procedural major adverse cardiovascular events (3.28% vs. 4.03%; p = 1.000). There were no significant differences in the secondary study endpoints. CONCLUSIONS: As compared with wire escalation, upfront use of the CrossBoss catheter for antegrade crossing of coronary chronic total occlusions was associated with similar crossing time, similar success and complication rates, and similar equipment use and cost.

The Medusa Multi-Coil Versus Alternative Vascular Plugs for Iliac Artery Aneurysm Embolization (MVP-EMBO) Study.

Transcatheter embolization has evolved from the use of autologous clot as the embolic agent, to stainless-steel coils, to braided-nitinol vascular plugs. However, there are disadvantages to platinum and metal coils, including procedural time, radiation exposure, mass effect, risk of distal embolization, recanalization, imaging artifacts, and cost. Therefore, a large vessel-occluding device is needed to mitigate these current disadvantages. The Medusa Multi-Coil (MMC; EndoShape, Inc) is a Food and Drug Administration (FDA)-approved embolization device constructed primarily of radioopaque coils with synthetic fibers to promote thrombogenicity, and a unique delivery platform with both proximal and distal attachment to assist with precise placement. We report our experience with the endovascular treatment of internal iliac artery aneurysms using platinum coils vs MMCs.

Intracardiac echocardiography: evolving use in interventional cardiology.

Intracardiac echocardiography (ICE) uses a catheter-based steerable ultrasound probe that is passed into the right heart chambers to image intracardiac structures. The transducer can be variably positioned for optimal imaging: in the inferior vena cava to visualize the abdominal aorta; in the right atrium for the interatrial septum, aortic, mitral, and tricuspid valves, and pulmonary veins; or in the right ventricle for the left ventricular function, outflow tract, or pulmonary artery. Intracardiac echocardiography is primarily used for imaging during an invasive cardiac procedure using conscious sedation, when transthoracic image quality would likely be inadequate, and transesophageal imaging would require general anesthesia. Intracardiac echocardiography is generally well tolerated and provides adequate images and sufficient information for the procedure performed. In the cardiac catheterization laboratory, ICE is routinely used for patent foramen ovale, atrial septal defect, and ventricular septal defect closures, allowing adequate percutaneous placement of septal occluders. It is now being considered in the current era of transcatheter aortic valve implantation necessitating improved imaging approaches for accurate placement. It is also routinely used for trans-septal punctures during mitral valvuloplasty and, more recently, with the advent of left atrial appendage closure devices. This article provides a comprehensive review of the current technology for ICE and its growing applications in the realm of interventional cardiology.

Purulent pericarditis caused by Haemophilus influenzae type B.

Purulent pericarditis, once a common entity associated with intrathoracic infections, such as pneumonia and empyema, has become an infrequent illness in the post-antibiotic era. Prompt recognition and therapy are vital in improving disease-related mortality. Herein, we describe a rare case of Haemophilus influenzae type B purulent pericarditis and associated cardiac tamponade. Antibiotic therapy, pericardial drainage, and subsequent pericardiectomy were performed with resolution of illness.

Regional cardiac tamponade resulting in hypoxia from acute right to left inter-atrial shunting.

Loculated pericardial effusion, as a cause of acute hypoxia, is an unusual finding. Here, we describe the case of a patient who underwent percutaneous coronary intervention, complicated by a localized pericardial hematoma compressing the right atrium, resulting in right to left shunting of blood through a patent foramen ovale and subsequent hypoxia. Evacuation of the hematoma was eventually performed via a pericardial window with resolution of hypoxia.