Ferumoxytol-enhanced MR Angiography for Vascular Access Mapping before Transcatheter Aortic Valve Replacement in Patients with Renal Impairment: A Step Toward Patient-specific Care.

Purpose To assess the technical feasibility of the use of ferumoxytol-enhanced (FE) magnetic resonance (MR) angiography for vascular mapping before transcatheter aortic valve replacement in patients with renal impairment. Materials and Methods This was an institutional review board-approved and HIPAA-compliant study. FE MR angiography was performed at 3.0 T or 1.5 T. Unenhanced computed tomographic (CT) images were used to overlay vascular calcification on FE MR angiographic images as composite fused three-dimensional data. Image quality of the subclavian and aortoiliofemoral arterial tree and confidence in the assessment of calcification were evaluated by using a four-point scale (4 = excellent vascular definition or strong confidence). Signal intensity nonuniformity as reflected by the heterogeneity index (ratio between the mean standard deviation of luminal signal intensity and the mean luminal signal intensity), signal-to-noise ratio, and consistency of luminal diameter measurements were quantified. Findings at FE MR angiography were compared with pelvic angiograms. Results Twenty-six patients underwent FE MR angiography without adverse events. A total of 286 named vascular segments were scored. The image quality score was 4 for 99% (283 of 286) of the segments (κ = 0.9). There was moderate to strong confidence in the ability to assess vascular calcific morphology in all studies with complementary unenhanced CT. The steady-state luminal heterogeneity index was low, and signal-to-noise ratio was high. Interobserver luminal measurements were reliable (intraclass correlation coefficient, 0.98; 95% confidence interval: 0.98, 0.99). FE MR angiographic findings were consistent with correlative pelvic angiograms in all 16 patients for whom the latter were available. Conclusion In patients with renal impairment undergoing transcatheter aortic valve replacement, FE MR angiography is technically feasible and offers reliable vascular mapping without exposure to iodine- or gadolinium-based contrast agents. Thus, the total cumulative dose of iodine-based contrast material is minimized and the risk of acute nephropathy is reduced. © RSNA, 2017 Online supplemental material is available for this article.

Defining the common femoral artery: Insights from the femoral arterial access with ultrasound trial.

OBJECTIVE: We sought to establish the typical location of the common femoral artery (CFA) bifurcation, the origin and most inferior reflection of the inferior epigastric artery (IEA) relative to the femoral head (FH) and whether patient demographics predicted anatomical variations. BACKGROUND: In the absence of ultrasound guidance or prior imaging, the precise location of the CFA bifurcation and IEA can only be determined following access site angiography. Fluoroscopic landmarks are commonly used to estimate the location of the CFA bifurcation, but the position of the IEA is less well characterized. METHODS: Prospectively collected data on 989 patients with femoral angiography in the FAUST trial were analyzed. The level of CFA bifurcation and the origin and most inferior reflection of the IEA were classified by angiography. Logistic regression was used to explore whether baseline demographics were associated with anatomic variations. RESULTS: The CFA bifurcation occurs below the middle 1/3rd of the femoral head in 95% of patients, and no patient factors are predictive of a high bifurcation. The IEA origin has a more variable anatomically pattern, with high BSA, male gender, and white race associated with a low IEA origin. CONCLUSION: Operators should attempt to access the CFA at the level of the middle 1/3rd of the FH to maximize the chance of CFA cannulation. However, this location carries an 11% risk of being at or above the IEA origin. Baseline demographics were of limited utility for predicting anatomic variants of the CFA bifurcation and the course of the IEA. © 2016 Wiley Periodicals, Inc.

Acute myocardial infarction caused by multivessel coronary spasm due to calcium channel blocker withdrawal.

Calcium channel blockers are a commonly used class of medications for the management of hypertension, angina, and superventricular tachyarrhythmias. Abrupt withdrawal of these agents can precipitate coronary vasospasm, which may result in myocardial infarction. We present the case of a 47-year-old woman who sustained an acute myocardial infarction mediated by multivessel coronary vasospasm secondary to verapamil withdrawal and the associated interventional management.

Suicide left ventricle following transcatheter aortic valve implantation.

In some patients with aortic stenosis, dynamic intraventricular gradients like those seen in hypertrophic obstructive cardiomyopathy may develop secondary to left ventricular hypertrophy from chronic pressure overload. With the advent of transcatheter aortic valve implantation, many patients with aortic stenosis and advanced age who formerly would be considered "too high risk" for aortic valve replacement are getting treatment for their aortic stenosis. This case highlights the hemodynamic aberrations that can occur with TAVI leading to a cautionary note regarding implementation of this rapidly emerging technique in patients with left ventricles that may be at risk for suicide left ventricle.

Transcatheter closure of a traumatic VSD in an adult requiring an ASD occluder device.

Traumatic ventricular septal defects (VSD) can occur after blunt or penetrating chest trauma or cardiac procedures. There are few publications reporting the safety and efficacy of transcatheter closure of traumatic VSDs. We report a case of a large VSD resulting from penetrating chest trauma that was not repaired at the initial surgical procedure on the disrupted right ventricle. Because of the late identification of the VSD postoperatively, transcatheter closure after the original surgical procedure was recommended and performed requiring an Amplatzer atrial septal defect occluder device because of defect size and configuration. This case describes the technique and postprocedure imaging leading to a cautionary note regarding VSD closure device techniques.

Addressing the hemodynamic dilemma of combined mitral and aortic stenosis.

Accurate assessment of valvular hemodynamics is essential in the decision-making process when referring a patient for cardiac surgery who has suspected coexistent aortic and mitral valve disease. Often times, one valvular lesion is worse than the other, and the question of "prophylactically" replacing the less severe valve at the time of surgery is controversial. In these situations and because of uncertainty regarding noninvasive assessment, hemodynamic evaluation in the cardiac catheterization laboratory provides critical information in guiding therapy.

Importance of electrocardiography in the assessment and management of heart failure: a case report.

Restoring and maintaining optimal electrical activation of the cardiac chambers as well as atrioventricular synchrony are important aspects of heart failure management. The 12-lead electrocardiogram remains a simple and cost-effective diagnostic tool that can provide important clues in achieving this goal. We report a case where careful interpretation of the 12-lead electrocardiogram led to the diagnosis of pacemaker syndrome. This recognition led to a therapeutic intervention that resulted in the resolution of the patient's heart failure symptoms. The importance of electrocardiography and atrioventricular synchrony in the management of heart failure will also be discussed.

Radial haemostasis is facilitated with a potassium ferrate haemostatic patch: the Statseal with TR Band assessment trial (STAT).

AIMS: Haemostasis is a limiting factor for discharge after uncomplicated transradial procedures. The purpose of this study was to determine whether a potassium ferrate haemostatic patch (PFHP) could serve as an adjunct to the air-bladder TR Band (TRB) to facilitate implementation of a rapid deflation protocol. METHODS AND RESULTS: This was a prospective multicentre randomised controlled trial comparing radial haemostatic protocols. Deflation of the TRB was attempted at 40 minutes with PFHP and at 120 minutes without the PFHP. The primary outcome was time to full deflation of the TRB with haemostasis. At four US sites, 180 patients were enrolled after receiving a minimum of 5,000 units of unfractionated heparin or bivalirudin. Interventions comprised 30% of procedures. Successful TRB deflation occurred at 43±14 minutes with PFHP and 160±43 minutes without PFHP (p<0.001). Minor haematomas occurred in nine (10.3%) of the TRB patients and 16 (17.2%) of the PFHP patients (p=0.20). Radial artery occlusion occurred in 2% of patients in the PFHP group (p=NS). Outpatients randomised to PFHP were discharged 51±83.5 minutes earlier than control. CONCLUSIONS: The PFHP haemostatic patch facilitated early deflation of the TRB with a non-significant increase in forearm haematomas. Use of the PFHP may improve patient throughput and allow earlier discharge following transradial procedures.

Acute lymphoblastic leukemia presenting as acute renal failure.

BACKGROUND: A 42-year-old previously healthy man presented with acute-onset headache and facial paralysis. He was treated for Bell's palsy with corticosteroids and valaciclovir. One week later, he developed acute renal failure requiring hospitalization. INVESTIGATION: Physical examination, laboratory tests, urinalysis, renal ultrasound, renal biopsy, bone marrow biopsy, lumbar puncture, CT of the chest, abdomen and pelvis, MRI of the brain, and whole-body PET scan. DIAGNOSIS: Acute lymphoblastic leukemia, bilateral renal enlargement secondary to leukemic infiltration, acute renal failure, tumor lysis syndrome, and leukemic involvement of the facial nerve. MANAGEMENT: The patient was treated with a modified induction chemotherapy regimen. He was given allopurinol for hyperuricemia and hydrated with alkalized intravenous fluids to prevent uric acid precipitation in the renal tubules. The profound tumor lysis that occurred after the cytotoxic chemotherapy required hemodialysis.

Utility of cardiac MRI in guiding revascularization therapy in unprotected left main stenosis: a case report.

Decision to select unprotected left main (ULM) stenting versus coronary artery bypass grafting surgery (CABG) depends on a multiplicity of factors, one of the most critical of which is myocardial viability. Delayed enhancement cardiac magnetic resonance (CMR) imaging has emerged as a useful means of comprehensively evaluating viable myocardium in postmyocardial infarct patients who require further revascularization. We present a patient with ULM stenosis in whom CMR imaging assisted in the decision to perform percutaneous coronary intervention over CABG.

3-D Electrochemical Impedance Spectroscopy Mapping of Arteries to Detect Metabolically Active but Angiographically Invisible Atherosclerotic Lesions.

We designed a novel 6-point electrochemical impedance spectroscopy (EIS) sensor with 15 combinations of permutations for the 3-D mapping and detection of metabolically active atherosclerotic lesions. Two rows of 3 stretchable electrodes circumferentially separated by 120° were mounted on an inflatable balloon for intravascular deployment and endoluminal interrogation. The configuration and 15 permutations of 2-point EIS electrodes allowed for deep arterial penetration via alternating current (AC) to detect varying degrees of lipid burden with distinct impedance profiles (Ω). By virtue of the distinctive impedimetric signature of metabolically active atherosclerotic lesions, a detailed impedance map was acquired, with the 15 EIS permutations uncovering early stages of disease characterized by fatty streak lipid accumulation in the New Zealand White rabbit model of atherosclerosis. Both the equivalent circuit and statistical analyses corroborated the 3-D EIS permutations to detect small, angiographically invisible, lipid-rich lesions, with translational implications for early atherosclerotic disease detection and prevention of acute coronary syndromes or strokes.

Coronary and bypass graft angiography via the right radial approach using a single catheter.

Transradial cardiac catheterization in patients with previous coronary artery bypass graft surgery can be technically challenging. The presence of a left internal mammary artery (LIMA) graft was previously considered a relative contraindication for a right radial procedure, but there are several reports demonstrating the feasibility and safety of LIMA angiography from a right radial access. This case report demonstrates that transradial coronary and bypass graft angiography including LIMA angiography from the right radial approach is technically feasible with a single catheter. Catheter options for LIMA angiography from right radial access will also be discussed.

Quantification of fractional flow reserve based on angiographic image data.

Coronary angiography provides excellent visualization of coronary arteries, but has limitations in assessing the clinical significance of a coronary stenosis. Fractional flow reserve (FFR) has been shown to be reliable in discerning stenoses responsible for inducible ischemia. The purpose of this study is to validate a technique for FFR quantification using angiographic image data. The study was carried out on 10 anesthetized, closed-chest swine using angioplasty balloon catheters to produce partial occlusion. Angiography based FFR was calculated from an angiographically measured ratio of coronary blood flow to arterial lumen volume. Pressure-based FFR was measured from a ratio of distal coronary pressure to aortic pressure. Pressure-wire measurements of FFR (FFR( P )) correlated linearly with angiographic volume-derived measurements of FFR (FFR( V )) according to the equation: FFR( P ) = 0.41 FFR( V ) + 0.52 (P-value < 0.001). The correlation coefficient and standard error of estimate were 0.85 and 0.07, respectively. This is the first study to provide an angiographic method to quantify FFR in swine. Angiographic FFR can potentially provide an assessment of the physiological severity of a coronary stenosis during routine diagnostic cardiac catheterization without a need to cross a stenosis with a pressure-wire.

Real-time ultrasound guidance facilitates femoral arterial access and reduces vascular complications: FAUST (Femoral Arterial Access With Ultrasound Trial).

OBJECTIVES: The aim of this study was to compare the procedural and clinical outcomes of femoral arterial access with ultrasound (US) guidance with standard fluoroscopic guidance. BACKGROUND: Real-time US guidance reduces time to access, number of attempts, and complications in central venous access but has not been adequately assessed in femoral artery cannulation. METHODS: Patients (n = 1,004) undergoing retrograde femoral arterial access were randomized 1:1 to either fluoroscopic or US guidance. The primary end point was successful common femoral artery (CFA) cannulation by femoral angiography. Secondary end points included time to sheath insertion, number of forward needle advancements, first pass success, accidental venipunctures, and vascular access complications at 30 days. RESULTS: Compared with fluoroscopic guidance, US guidance produced no difference in CFA cannulation rates (86.4% vs. 83.3%, p = 0.17), except in the subgroup of patients with CFA bifurcations occurring over the femoral head (82.6% vs. 69.8%, p < 0.01). US guidance resulted in an improved first-pass success rate (83% vs. 46%, p < 0.0001), reduced number of attempts (1.3 vs. 3.0, p < 0.0001), reduced risk of venipuncture (2.4% vs. 15.8%, p < 0.0001), and reduced median time to access (136 s vs. 148 s, p = 0.003). Vascular complications occurred in 7 of 503 and 17 of 501 in the US and fluoroscopy groups, respectively (1.4% vs. 3.4% p = 0.04). CONCLUSIONS: In this multicenter randomized controlled trial, routine real-time US guidance improved CFA cannulation only in patients with high CFA bifurcations but reduced the number of attempts, time to access, risk of venipunctures, and vascular complications in femoral arterial access. (Femoral Arterial Access With Ultrasound Trial [FAUST]; NCT00667381).

Violent hiccups: an infrequent cause of bradyarrhythmias.

A hiccup, or singultus, results from a sudden, simultaneous, vigorous contraction of the diaphragm and inspiratory muscles, accompanied by closure of the glottis. Hiccups can be associated with bradyarrhythmias. The mechanism of this phenomenon is likely hiccup-induced Valsalva maneuver and increased parasympathetic tone. We present a case of a patient with violent hiccups producing a bradyarrhythmia.

Successful catheter ablation of focal ventricular fibrillation originating from the right ventricle.

Sudden cardiac death from ventricular fibrillation (VF) typically occurs in patients with structural heart disease, but in 5 to 10 percent VF is "idiopathic," occurring in normal hearts. Recently, there has been the description and growing recognition of patients with VF that has a focal origin, the common sites being in the right ventricular outflow tract (RVOT) and sites in the left ventricle. A focus within the right ventricle outside the RVOT is rare. We present a case of a woman with VF storm that was localized to the inferobasal right ventricle and was successfully treated with radiofrequency ablation.