Stacie VanOosterhout

Large lipid-rich coronary plaques detected by near-infrared spectroscopy at non-stented sites in the target artery identify patients likely to experience future major adverse cardiovascular events

AIMS A recent study demonstrated that intracoronary near-infrared spectroscopy (NIRS) findings in non-target vessels are associated with major adverse cardiovascular and cerebrovascular events (MACCE). It is unknown whether NIRS findings at non-stented sites in target vessels are similarly associated with future MACCE. This study evaluated the association between large lipid-rich plaques (LRP) detected by NIRS at non-stented sites in a target artery and subsequent MACCE. METHODS AND RESULTS This study evaluated 121 consecutive registry patients undergoing NIRS imaging in a target artery. After excluding stented segments, target arteries were evaluated for a large LRP, defined as a maximum lipid core burden index in 4 mm (maxLCBI4 mm) ≥400. Excluding events in stented segments, Cox regression analysis was performed to evaluate for an association between a maxLCBI4 mm ≥400 and future MACCE, defined as all-cause mortality, non-fatal acute coronary syndrome, and cerebrovascular events. NIRS detected a maxLCBI4 mm ≥400 in a non-stented segment of the target artery in 17.4% of patients. The only baseline clinical variable marginally associated with MACCE was ejection fraction (HR 0.96, 95% CI 0.93-1.00, P = 0.054). A maxLCBI4 mm ≥400 in a non-stented segment at baseline was significantly associated with MACCE during follow-up (HR 10.2, 95% CI 3.4-30.6, P < 0.001). CONCLUSION Detection of large LRP by NIRS at non-stented sites in a target artery was associated with an increased risk of future MACCE. These findings support ongoing prospective studies to further evaluate the ability of NIRS to identify vulnerable patients.

Cardiac Perforation and Lead Dislodgement after Implantation of a MR-Conditional Pacing Lead: A Single-Center Experience

The purpose of our study was to determine if the rate of lead‐related complications was increased with the Medtronic CapSureFix MRI™ SureScan™ 5086 MRI pacing lead (5086; Medtronic Inc., Minneapolis, MN, USA) compared to the previous generation of Medtronic CapSureFix Novus™ 5076 pacing lead (5076).

Confirmation of the Intracoronary Near-Infrared Spectroscopy Threshold of Lipid-Rich Plaques That Underlie ST-Segment–Elevation Myocardial Infarction

Objective—In a previous exploratory analysis, intracoronary near-infrared spectroscopy (NIRS) found the majority of culprit lesions in ST-segment–elevation myocardial infarction (STEMI) to contain a maximum lipid core burden index in 4 mm (maxLCBI4mm) of >400. This initial study was limited by a small sample size, enrollment at a single center, and post hoc selection of the maxLCBI4mm ≥400 threshold. This study was designed a priori to substantiate the ability of NIRS to discriminate STEMI culprit from nonculprit segments and to confirm the performance of the maxLCBI4mm ≥400 threshold. Approach and Results—At 2 centers in the United States and Sweden, 75 STEMI patients underwent intracoronary NIRS imaging after establishing thrombolysis in myocardial infarction 3 flow, but before stenting. Blinded core laboratory analysis defined the culprit segment as the 10-mm segment distal to the proximal angiographic culprit margin. The remaining vessel was divided into contiguous 10-mm nonculprit segments. The maxLCBI4mm of culprit segments (median [interquartile range]: 543 [273–756]) was 4.4-fold greater than nonculprit segments (median [interquartile range]: 123 [0–307]; P<0.001). Receiver-operating characteristic analysis demonstrated that maxLCBI4mm differentiated culprit from nonculprit segments with high accuracy (c-statistic=0.83; P<0.001). A threshold maxLCBI4mm ≥400 identified STEMI culprit segments with a sensitivity of 64% and specificity of 85%. Conclusions—This study substantiates the ability of NIRS to accurately differentiate STEMI culprit from nonculprit segments and confirms that a threshold maxLCBI4mm ≥400 is detected by NIRS in the majority of STEMI culprits.

Impact of an emergency department-initiated clinical protocol for the evaluation and treatment of atrial fibrillation.

OBJECTIVE Published data supporting the best practice for patients with atrial fibrillation (AF) presenting to the emergency department (ED) are limited. Our objective was to evaluate the impact of an AF clinical protocol initiated in the ED with early follow-up in a specialty AF outpatient clinic. METHODS This was a single-center prospective study of all consented patients with AF who were discharged from the ED through the AF clinical pathway and were then seen in the AF clinic. The primary endpoint was the rate of 90-day hospitalization/ED visits. Secondary endpoints included adherence to established AF anticoagulation guidelines, rate of thromboembolic events, quality of life, and patient satisfaction. RESULTS One hundred consecutive patients were enrolled in the study. Within 90 days, 15 had ED visits and 4 were hospitalized, whereas none developed thromboembolic complications. There were significant increases in the Atrial Fibrillation Effect on QualiTy of life survey quality of life (67.3 ± 24.8 vs. 89.2 ± 15.7; P < 0.001) and patient satisfaction (66.4 ± 25.3 vs. 77.9 ± 22.8; P < 0.001) scores from baseline to 90 days. Of the 29 patients with CHADS2 score ≥2, 20 (69%) were discharged from the AF clinic with oral anticoagulation. CONCLUSIONS We describe a novel approach to the care of patients with AF presenting to the ED. Usage of the ED-initiated AF clinical pathway with early follow-up in a protocol-driven AF clinic was associated with low readmission rates, no thromboembolic complications at 90 days, improved quality of life, and high patient satisfaction.

Percutaneous coronary intervention using a combination of robotics and telecommunications by an operator in a separate physical location from the patient: an early exploration into the feasibility of telestenting (the REMOTE-PCI study)

AIMS The present study explores the feasibility of telestenting, wherein a physician operator performs stenting on a patient in a separate physical location using a combination of robotics and telecommunications. METHODS AND RESULTS Patients undergoing robotic stenting were eligible for inclusion. All manipulations of guidewires, balloons, and stents were performed robotically by a physician operator located in an isolated separate room outside the procedure room housing the patient. Communication between the operating physician and laboratory personnel was via telecommunication devices providing real-time audio and video connectivity. Among 20 patients who consented to participate, technical success, defined as successful advancement and retraction of guidewires, balloons, and stents by the robotic system without conversion to manual operation, was achieved in 19 of 22 lesions (86.4%). Procedural success, defined as <30% residual stenosis upon completion of the procedure in the absence of death or repeat revascularisation prior to hospital discharge, was achieved in 19 of 20 patients (95.0%). There were no deaths or repeat revascularisations prior to hospital discharge. CONCLUSIONS To the best of our knowledge, the present study is the first to explore the feasibility of telestenting. Additional studies are required to determine if future advancements in robotics will facilitate telestenting over greater geographic distances.

Impact of robotics and a suspended lead suit on physician radiation exposure during percutaneous coronary intervention

BACKGROUND Reports of left-sided brain malignancies among interventional cardiologists have heightened concerns regarding physician radiation exposure. This study evaluated the impact of a suspended lead suit and robotic system on physician radiation exposure during percutaneous coronary intervention (PCI). METHODS Real-time radiation exposure data were prospectively collected from dosimeters worn by operating physicians at the head- and chest-level during consecutive PCI cases. Exposures were compared in three study groups: 1) manual PCI performed with traditional lead apparel; 2) manual PCI performed using suspended lead; and 3) robotic PCI performed in combination with suspended lead. RESULTS Among 336 cases (86.6% manual, 13.4% robotic) performed over 30weeks, use of suspended lead during manual PCI was associated with significantly less radiation exposure to the chest and head of operating physicians than traditional lead apparel (chest: 0.0 [0.1] μSv vs 0.4 [4.0] μSv, p<0.001; head: 0.5 [1.9] μSv vs 14.9 [51.5] μSv, p<0.001). Chest-level radiation exposure during robotic PCI performed in combination with suspended lead was 0.0 [0.0] μSv, which was significantly less chest exposure than manual PCI performed with traditional lead (p<0.001) or suspended lead (p=0.046). In robotic PCI the median head-level exposure was 0.1 [0.2] μSv, which was 99.3% less than manual PCI performed with traditional lead (p<0.001) and 80.0% less than manual PCI performed with suspended lead (p<0.001). CONCLUSIONS Utilization of suspended lead and robotics were observed to result in significantly less radiation exposure to the chest and head of operating physicians during PCI.

Combined Near-Infrared Spectroscopy and Intravascular Ultrasound Imaging of Pre-Existing Coronary Artery Stents Can Near-Infrared Spectroscopy Reliably Detect Neoatherosclerosis?

Background—Neoatherosclerosis is an emerging phenomenon in which lipid-rich plaques (LRPs) develop within pre-existing stents. This study was undertaken to describe near-infrared spectroscopy (NIRS) and intravascular ultrasound findings in pre-existing stents and to compare NIRS findings in pre-existing stents, in which an increased lipid signal has been speculated to indicate neoatherosclerosis, and NIRS findings in a control group of freshly implanted stents, in which any lipid signal originates from fibroatheroma under the stent. Methods and Results—At the site of LRP detected by NIRS in a cohort of pre-existing stents, intravascular ultrasound was used to determine the presence of neointimal tissue. The lipid-core burden index and maximum lipid-core burden index in 4 mm were measured within stented segments. Findings were compared between pre-existing stents and a control group of freshly implanted stents. Among 60 pre-existing stents implanted 5.5±4.0 years earlier, NIRS detected LRP in 33%. At the site of LRP, intravascular ultrasound found no neointimal tissue in 35% of cases. NIRS findings in pre-existing stents were indistinguishable from those of freshly implanted stents (lipid-core burden index: 50±72 versus 42±58; P=0.40 and maximum lipid-core burden index in 4 mm: 156±184 versus 155±203; P=0.69). Conclusions—The detection of LRP in a pre-existing stent by NIRS alone is not reliable evidence of neoatherosclerosis, as the lipid signal may originate from fibroatheroma underlying the stent. By identifying the presence or absence of neointimal tissue at the site of LRP detected by NIRS, intravascular ultrasound may provide some insight into the potential source of the lipid signal in pre-existing stents. Registration Information—URL: http://www.clinicaltrials.gov. Unique identifier: NCT01694368.

Multimodality Intracoronary Imaging With Near-Infrared Spectroscopy and Intravascular Ultrasound in Asymptomatic Individuals With High Calcium ScoresCLINICAL PERSPECTIVE

Background— This study sought to determine the frequency of large lipid-rich plaques (LRP) in the coronary arteries of individuals with high coronary artery calcium scores (CACS) and to determine whether the CACS correlates with coronary lipid burden. Methods and Results— Combined near-infrared spectroscopy and intravascular ultrasound was performed in 57 vessels in 20 asymptomatic individuals (90% on statins) with no prior history of coronary artery disease who had a screening CACS ≥300 Agatston units. Among 268 10-mm coronary segments, near-infrared spectroscopy images were analyzed for LRP, defined as a bright yellow block on the near-infrared spectroscopy block chemogram. Lipid burden was assessed as the lipid core burden index (LCBI), and large LRP were defined as a maximum LCBI in 4 mm ≥400. Vessel plaque volume was measured by quantitative intravascular ultrasound. Vessel-level CACS significantly correlated with plaque volume by intravascular ultrasound (r=0.69; P<0.0001) but not with LCBI by near-infrared spectroscopy (r=0.24; P=0.07). Despite a high CACS, no LRP was detected in 8 (40.0%) subjects. Large LRP having a maximum LCBI in 4 mm ≥400 were infrequent, found in only 5 (25.0%) of 20 subjects and in only 5 (1.9%) of 268 10-mm coronary segments analyzed. Conclusions— Among individuals with a CACS ≥300 Agatston units mostly on statins, CACS correlated with total plaque volume but not LCBI. This observation may have implications on coronary risk among individuals with a high CACS considering that it is coronary LRP, rather than calcification, that underlies the majority of acute coronary events.

Response by Madder et al to Letter Regarding Article, “Multimodality Intracoronary Imaging With Near-Infrared Spectroscopy and Intravascular Ultrasound in Asymptomatic Individuals With High Calcium Scores”

We agree with Drs Shaikh and Budoff on the necessity of additional studies to investigate whether detection of lipid-rich plaque (LRP) by near-infrared spectroscopy (NIRS) can add incremental value to the coronary artery calcium score (CACS) in the prediction of future cardiovascular events. In our recent study, we demonstrated that NIRS adds information on the presence or absence of LRP among individuals with a high CACS.1 A logical next step is to determine if …

Impact of patient obesity on radiation doses received by scrub technologists during coronary angiography

BACKGROUND The impact of patient obesity on scrub technologist radiation dose during coronary angiography has not been adequately studied. METHODS Real-time radiation exposure data were prospectively collected during consecutive coronary angiography cases. Patient radiation dose was estimated by dose area product (DAP). Technologist radiation dose was recorded by a dosimeter as the personal dose equivalent (Hp (10)). Patients were categorized according to their body mass index (BMI): <25.0, lean; 25.0-29.9, overweight; ≥30.0, obese. The study had two phases: in Phase I (N = 351) standard radiation protection measures were used; and in Phase II (N = 268) standard radiation protection measures were combined with an accessory lead shield placed between the technologist and patient. RESULTS In 619 consecutive coronary angiography procedures, significant increases in patient and technologist radiation doses were observed across increasing patient BMI categories (p < 0.001 for both). Compared to lean patients, patient obesity was associated with a 1.7-fold increase in DAP (73.0 [52.7, 127.5] mGy × cm2 vs 43.6 [25.1, 65.7] mGy × cm2, p < 0.001) and a 1.8-fold increase in technologist radiation dose (1.1 [0.3, 2.7] μSv vs 0.6 [0.1, 1.6] μSv, p < 0.001). Compared to Phase I, use of an accessory lead shield in Phase II was associated with a 62.5% reduction in technologist radiation dose when used in obese patients (p < 0.001). CONCLUSIONS During coronary angiography procedures, patient obesity was associated with a significant increase in scrub technologist radiation dose. This increase in technologist radiation dose in obese patients may be mitigated by use of an accessory lead shield.