Trial of a Novel Radiation Shielding Device to Protect Staff in the Cardiac Catheter Laboratory.

Continuous exposure to low-level scattered radiation to staff performing cardiac angiography and intervention is of concern. A novel shielding solution (NSS) (Rampart IC M1128) has the potential to provide greater shielding for staff present at the table-side. This study aimed to investigate the effectiveness of the NSS compared with a traditional shielding solution (TSS) in a randomized controlled trial that enrolled 100 patients who underwent cardiac angiography and/or intervention which were randomized to the NSS or TSS. Baseline patient characteristics and radiation dose data were collected. Staff who were scrubbed at the table-side wore 5 real-time dosimeters on the head, collar, waist, ankle, and under the apron. The median primary operator radiation dose was significantly lower (p <0.001) for all dosimeter locations with the NSS when compared with the TSS, being reduced by 86%, 80.0%, 100%, and 50.0% for the head, collar, waist, and leg respectively. Median under-apron dose was 0.0 µSv for both NSS and TSS. Median second operator dose was reduced by 100%, 100%, and 100% for the head, collar, and waist respectively (p <0.001). Median NSS and TSS dose at the ankle and under apron was 0.0 µSv. Median scrub nurse dose was reduced by 50% and 100% for the head and collar respectively (p <0.001). Median NSS and TSS dose at the waist, ankle, and under apron was 0.0 µSv. In conclusion, the NSS tested in this study demonstrates a significant decrease in radiation dose to operators and scrub nurses when compared with traditional radiation protection measures.

Coronary plaque and clinical characteristics of South Asian (Indian) patients with acute coronary syndromes: An optical coherence tomography study.

BACKGROUND: South Asians, and Indians in particular, are known to have a higher incidence of premature atherosclerosis and acute coronary syndromes (ACS) with worse clinical outcomes, compared to populations with different ethnic backgrounds. However, the underlying pathobiology accounting for these differences has not been fully elucidated. METHODS: ACS patients who had culprit lesion optical coherence tomography (OCT) imaging were enrolled. Culprit plaque characteristics were evaluated using OCT. RESULTS: Among 1315 patients, 100 were South Asian, 1009 were East Asian, and 206 were White. South Asian patients were younger (South Asians vs. East Asians vs. Whites: 51.6 ± 13.4 vs. 65.4 ± 11.9 vs. 62.7 ± 11.7; p < 0.001) and more frequently presented with ST-segment elevation myocardial infarction (STEMI) (77.0% vs. 56.4% vs. 35.4%; p < 0.001). On OCT analysis after propensity group matching, plaque erosion was more frequent (57.0% vs. 38.0% vs. 50.0%; p = 0.003), the lipid index was significantly greater (2281.6 [1570.8-3160.6] vs. 1624.3 [940.9-2352.4] vs. 1303.8 [1090.0-1757.7]; p < 0.001), and the prevalence of layered plaque was significantly higher in the South Asian group than in the other two groups (52.0% vs. 30.0% vs. 34.0%; p = 0.003). CONCLUSIONS: Compared to East Asians and Whites, South Asians with ACS were younger and more frequently presented with STEMI. Plaque erosion was the predominant pathology for ACS in South Asians and their culprit lesions had more features of plaque vulnerability. CLINICAL TRIAL REGISTRATION: http://www.clinicaltrials.gov, NCT03479723.

Radiation Exposure of Operators Performing Transesophageal Echocardiography During Percutaneous Structural Cardiac Interventions.

BACKGROUND: Transesophageal echocardiography operators (TEEOP) provide critical imaging support for percutaneous structural cardiac intervention procedures. They stand close to the patient and the associated scattered radiation. OBJECTIVES: This study sought to investigate TEEOP radiation dose during percutaneous structural cardiac intervention. METHODS: Key personnel (TEEOP, anesthetist, primary operator [OP1], and secondary operator) wore instantly downloadable personal dosimeters during procedures requiring TEE support. TEEOP effective dose (E) and E per unit Kerma area product (E/KAP) were calculated. E/KAP was compared with C-arm projections. Additional shielding for TEEOP was implemented, and doses were measured for a further 50 procedures. Multivariate linear regression was performed to investigate independent predictors of radiation dose reduction. RESULTS: In the initial 98 procedures, median TEEOP E was 2.62 µSv (interquartile range [IQR]: 0.95 to 4.76 µSv), similar to OP1 E: 1.91 µSv (IQR: 0.48 to 3.81 µSv) (p = 0.101), but significantly higher than secondary operator E: 0.48 µSv (IQR: 0.00 to 1.91 µSv) (p < 0.001) and anesthetist E: 0.48 µSv (IQR: 0.00 to 1.43 µSv) (p < 0.001). Procedures using predominantly right anterior oblique (RAO) and steep RAO projections were associated with high TEEOP E/KAP (p = 0.041). In a further 50 procedures, with additional TEEOP shielding, TEEOP E was reduced by 82% (2.62 µSv [IQR: 0.95 to 4.76] to 0.48 µSv [IQR: 0.00 to 1.43 µSv] [p < 0.001]). Multivariate regression demonstrated shielding, procedure type, and KAP as independent predictors of TEEOP dose. CONCLUSION: TEE operators are exposed to a radiation dose that is at least as high as that of OP1 during percutaneous cardiac intervention. Doses were higher with procedures using predominantly RAO projections. Radiation doses can be significantly reduced with the use of an additional ceiling-suspended lead shield.

Retrospective Study of First-Generation Drug-Eluting Stents, Second-Generation Drug-Eluting Stents and Non-Drug Eluting Stent Methods in the Treatment of Native Vessel In-Stent Restenosis in Real-World Clinical Practice.

BACKGROUND: The efficacy of second-generation drug-eluting stents (DES) in treating in-stent restenosis (ISR) compared to first-generation DES and non-DES treatment methods in real-world cohorts has not yet been adequately addressed. This research intends to examine optimum treatment of in-stent restenosis, considering first-generation DES, second-generation DES and non-DES treatment methods in a real-world cohort. METHODS: Retrospective analysis was performed on 114 patients treated for native-vessel BMS or DES ISR. Thirty-two were treated with a first-generation DES (81% sirolimus, 19% paclitaxel), 32 with a second-generation DES (72% everolimus, 28% zotarolimus) and 28 with non-DES methods (32% bare-metal stent, 39% balloon angioplasty, 29% cutting balloon). The composite primary endpoint was total adverse cardiac events, recurrent stable angina, unstable angina, myocardial infarction (MI), target vessel revascularisation (TVR) and cardiac death at minimum clinical follow-up of six months. RESULTS: Primary endpoint rates were significantly higher in the non-DES and second-generation DES treatment groups than in first-generation DES (42.9%, 25.9%, 6.2%; p=0.004). Rates of MI and TVR were significantly higher in the non-DES treatment group, compared to first and second-generation DES (MI: 17.9%, 0%, 5.6%; p=0.018; TLR: 21.4%, 3.1%, 7.4%; p=0.041). CONCLUSIONS: First-generation DES may be superior to second-generation DES and non-DES in treating BMS or DES ISR with regard to overall adverse cardiac events.

Quantitative analysis of the side-branch orifice after bifurcation stenting using en-face processing of OCT images: a comparison between Xience V and Resolute Integrity stents.

OBJECTIVE: Methods for intravascular assessment of the side-branch (SB) orifice after stenting are not readily available. The aim of this study was to assess the utility of an en-face projection processing for optical coherence tomography (OCT) images for SB evaluation. METHODS: Measurements of the SB orifice obtained using en-face OCT images were validated using a phantom model. Linear regression modeling was applied to estimated area measurements made on the en-face images. The SB orifice was then analyzed in 88 patients with bifurcation lesions treated with either Xience V (everolimus-eluting stent) or Resolute Integrity [zotarolimus-eluting stent (ZES)]. The SB orifice area (A) and the area obstructed by struts (B) were calculated, and the %open area was evaluated as (A-B)/A*100. RESULTS: Linear regression modeling demonstrated that the observed departures of the intercept and slope were not significantly different from 0 (-0.12 ± 0.22, P=0.59) and 1 (1.01 ± 0.06, R(2)=0.88, P=0.87), respectively. In cases without SB dilatation, the %open area was significantly larger in the everolimus-eluting stent group (n=25) than in the ZES group [n=32; 89.2% (83.7-91.3) vs. 84.3% (78.9-87.8), P=0.04]. A significant difference in %open area between cases with and those without SB dilatation was demonstrated in the ZES group [91.4% (86.1-94.0) vs. 84.3% (78.9-87.8), P=0.04]. CONCLUSION: The accuracy of SB orifice measurement on an en-face OCT image was validated using a phantom model. This novel approach enables quantitative evaluation of the differences in SB orifice area free from struts among different stent types and different treatment strategies in vivo.

Factors Contributing to Acute Kidney Injury and the Impact on Mortality in Patients Undergoing Transcatheter Aortic Valve Replacement.

BACKGROUND: Transcatheter aortic valve replacement (TAVR) patients are at a high risk of acute kidney injury (AKI). This study aimed to investigate AKI and the relationship with iodinated contrast media (ICM), whether there are significant pre- or peri- procedural variables predicting AKI, and whether AKI impacts on hospital length of stay and mortality. METHODS: Serum creatinine (SC) levels pre- and post- (peak) TAVR were recorded in 209 consecutive TAVR patients. AKI was defined by the Valve Academic Research Consortium 2 (VARC2) criteria. Baseline characteristics, procedural variables, hospital length of stay (LOS) and mortality at 72hours, 30 days and one year were analysed. RESULTS: Eighty-two of 209 (39%) patients suffered AKI. Mean ICM volume was 228cc, with no difference between patients with AKI and those with no AKI (227cc (213-240(95%CI)) vs 231cc (212-250) p=0.700)). Univariate and multivariate analysis demonstrated that chronic kidney disease, respiratory failure, previous stroke, the need for blood transfusion and valve repositioning were all predictors of AKI. Acute kidney injury increased LOS (5.6 days (3.8 - 7.5) vs 3.2 days (2.6 - 3.9) no AKI (P=0.004)) but was not linked to increased mortality. Mortality rates did increase with AKI severity. CONCLUSION: Acute kidney injury is a common complication of TAVR. The severity of AKI is important in determining mortality. Acute kidney injury appears to be independent of ICM use but pre-existing renal impairment and respiratory failure were predictors for AKI. Transcatheter aortic valve replacement device repositioning or retrieval was identified as a new risk factor impacting on AKI.

The effect of X-ray beam distortion on the Edwards Sapien XT(™) trans-catheter aortic valve replacement prosthesis.

INTRODUCTION: Profiling the Aortic root perpendicular to the fluoroscopic image plane will achieve a more successful implant position for trans-catheter aortic valve replacement (TAVR). This study aimed to investigate whether the divergent nature of the X-ray beam from the C-arm altered the appearance of the TAVR device. METHODS: Under bench-top testing, a 23, 26 and 29 mm Edwards Sapien XT valve was positioned coaxially at the bottom of a fluoroscopic image utilising 22 and 32 cm fields of view (FOV). The table was then moved so that the valve was positioned at the top of the image. The valve's appearance was scored using a previously published three tier classification tool (excellent, satisfactory and poor) and quantified with measurements. The number of degrees of C-arm rotation that were required to bring the valve back to a coaxial appearance was recorded. RESULTS: When using the 32 cm FOV, the valve's appearance changes from excellent to satisfactory. When a 22 cm FOV was used, the change is less marked. More C-arm rotation is required to bring the appearance back to coaxial with the 32 cm FOV. CONCLUSION: Not maintaining the valve in the centre of the image can distort the valves appearance. This has the potential to affect the final implantation depth.

Using DynaCT for the assessment of ilio-femoral arterial calibre, calcification and tortuosity index in patients selected for trans-catheter aortic valve replacement.

Adequate vascular access for femoral trans-catheter aortic valve replacement is fundamental to the success of the procedure. Assessment of vascular calibre, tortuosity and calcification is performed by angiography and multi-slice computed tomography (MSCT). Can DynaCT provide the same information as MSCT? 15 Patients underwent MSCT, angiography and DynaCT. Vessel diameter measurements were taken in three positions of the left and right ilio-femoral arteries. Tortuosity was assessed using an index of the direct distance and the distance taken by the artery between two points. Calcification was assessed in MSCT and DynaCT using a simple scoring system. Concordance correlation coefficient of arterial calibre between angiography and MSCT was 0.96 (95 % CI 0.94-0.97). DynaCT and angiography was 0.94 (95 % CI 0.91-0.96) and Dyna CT and MSCT, 0.95 (95 % CI 0.92-0.97). Bland-Altman tests demonstrate a mean difference between the angiogram and the MSCT of 0.06 mm (+0.97, -1.42), angiogram and DynaCT, 0.13 mm, (+1.00, -0.87), DynaCT and MSCT, 0.2 mm, (+1.15, -0.76). Tortuosity comparisons gave a median tortuosity index for MSCT 1.29 and DynaCT 1.23 (p = 0.472). Calcification comparisons of MSCT and DynaCT using correlation coefficients demonstrate a correlation of 0.245 (p = 0.378). Effective radiation doses were: DynaCT; 3.63 ± 0.65 mSv and angiography; 0.57 ± 0.72 mSv, MSCT; 7.15 ± 2.58 mSv. DynaCT is equal to MSCT and angiography in assessing femoral artery calibre. Like MSCT, it can assess tortuosity and can produce 3D images but is inferior in the assessment of calcification.

In vivo diagnosis of plaque erosion and calcified nodule in patients with acute coronary syndrome by intravascular optical coherence tomography.

OBJECTIVES: The aim of this study was to characterize the morphological features of plaque erosion and calcified nodule in patients with acute coronary syndrome (ACS) by optical coherence tomography (OCT). BACKGROUND: Plaque erosion and calcified nodule have not been systematically investigated in vivo. METHODS: A total of 126 patients with ACS who had undergone pre-intervention OCT imaging were included. The culprit lesions were classified as plaque rupture (PR), erosion (OCT-erosion), calcified nodule (OCT-CN), or with a new set of diagnostic criteria for OCT. RESULTS: The incidences of PR, OCT-erosion, and OCT-CN were 43.7%, 31.0%, and 7.9%, respectively. Patients with OCT-erosion were the youngest, compared with those with PR and OCT-CN (53.8 ± 13.1 years vs. 60.6 ± 11.5 years, 65.1 ± 5.0 years, p = 0.005). Compared with patients with PR, presentation with non-ST-segment elevation ACS was more common in patients with OCT-erosion (61.5% vs. 29.1%, p = 0.008) and OCT-CN (100% vs. 29.1%, p < 0.001). The OCT-erosion had a lower frequency of lipid plaque (43.6% vs. 100%, p < 0.001), thicker fibrous cap (169.3 ± 99.1 µm vs. 60.4 ± 16.6 µm, p < 0.001), and smaller lipid arc (202.8 ± 73.6° vs. 275.8 ± 60.4°, p < 0.001) than PR. The diameter stenosis was least severe in OCT-erosion, followed by OCT-CN and PR (55.4 ± 14.7% vs. 66.1 ± 13.5% vs. 68.8 ± 12.9%, p < 0.001). CONCLUSIONS: Optical coherence tomography is a promising modality for identifying OCT-erosion and OCT-CN in vivo. The OCT-erosion is a frequent finding in patients with ACS, especially in those with non-ST-segment elevation ACS and younger patients. The OCT-CN is the least common etiology for ACS and is more common in older patients. (The Massachusetts General Hospital Optical Coherence Tomography Registry; NCT01110538).

Hyperglycemia on admission predicts larger infarct size in patients undergoing percutaneous coronary intervention for acute ST-segment elevation myocardial infarction.

AIMS: To determine if hyperglycemia on admission correlates to infarct size measured by single-photon emission computed tomography (SPECT) in patients with acute ST-segment elevation myocardial infarction (STEMI) treated with primary percutaneous coronary intervention (PCI). METHODS: We evaluated 347 STEMI patients who underwent primary PCI. Infarct size was determined by SPECT on Day 5. The population was divided into: hyperglycemia (glycemia on admission >11mmol/L) or non-hyperglycemia (

Non-invasive assessment of myocardial ischaemia by using low amplitude oscillations of the conventional ECG signals (ECG dispersion mapping) during percutaneous coronary intervention.

OBJECTIVE: The HeartVue 6S System is a recently developed novel technology that may provide non-invasive assessment of myocardial ischaemia by analysing low amplitude oscillations of the conventional ECG signals (ECG dispersion mapping). The available data to validate this new technology is limited. Therefore we performed a prospective study to assess the HeartVue 6S System for the detection of myocardial ischaemia during coronary occlusion in patients undergoing percutaneous coronary intervention (PCI). METHODS: A total of 101 patients undergoing cardiac catheterization were prospectively enrolled. HeartVue 6S System ECG dispersion mapping was obtained at baseline, and during the first balloon inflation and at the end of the procedure if PCI was performed. Parameters provided by the HeartVue 6S System were analysed. RESULTS: Fifty patients who underwent PCI comprised the final study population. The mean age was 63.7 +/- 10 years and 58% were men. In 58% of cases the indication was acute coronary syndrome. In 98% of patients, PCI was successful. There were significant differences in the G7+G9 values between the first inflation and the end of the procedure, which reflect changes in ventricular depolarization (P = 0.02 by Wilcoxon signed rank test). CONCLUSIONS: The HeartVue 6S System may have potential for a non-invasive assessment of ischaemia in patients with suspected coronary artery disease. Larger studies are warranted to confirm these preliminary findings.

Pilot study to assess the influence of beta-blockade on mitral regurgitant volume and left ventricular work in degenerative mitral valve disease.

BACKGROUND: A medical treatment that decreases the likelihood of left ventricular (LV) dysfunction or symptoms would benefit patients with moderate to severe degenerative mitral regurgitation. The aim of this pilot study was to determine the short-term effects of a beta-blocker on mitral regurgitant volume and LV work in these patients. METHODS AND RESULTS: Twenty-five patients with moderate or severe degenerative mitral regurgitation were randomized in a double-blind crossover study to the beta(1)-selective adrenergic blocker metoprolol (mean daily dose, 119 mg; range 23.75 to 190 mg) and placebo for 14+/-3 days. At the end of each treatment period, ascending aortic flow and LV stroke volume were measured by cardiac magnetic resonance imaging, and mitral regurgitant volume was calculated. On beta-blocker, heart rate decreased from 65+/-10 by 10+/-7 bpm (mean+/-SD) and systolic blood pressure decreased from 138+/-18 by 16+/-12 mm Hg (P<0.0001 for both). No significant change occurred in LV ejection fraction (from 65+/-5%; change, -0.6+/-2.7%; P=0.3) or mitral regurgitant volume (from 59+/-36 mL; change, 3+/-13 mL; P=0.3), but forward stroke volume increased from 89+/-21 by 5+/-11 mL (P=0.03). Because heart rate was lower on metoprolol, cardiac output decreased from 5.68+/-1.04 by 0.56+/-0.78 L/min (P=0.001), but a greater decrease occurred in LV output, from 9.51+/-2.22 by 1.30+/-1.08 L/min (P<0.0001). Mitral regurgitant volume per minute decreased from 3.83+/-2.41 by 0.74+/-1.00 L/min (P=0.001). The decrease in LV work on beta-blocker (mean, 21%; 95% confidence interval, 15 to 27) was greater (P=0.001) than the decrease in cardiac output (mean, 9%; 95% confidence interval, 3 to 15). CONCLUSIONS: In this pilot study, short-term treatment with a beta-blocker did not change mitral regurgitant volume per beat but decreased LV work in patients with moderate to severe degenerative mitral regurgitation. Further research is needed to determine whether longer-term treatment with beta-blockers will decrease progressive LV dysfunction and symptomatic deterioration.

Mapping of mitral regurgitant defects by cardiovascular magnetic resonance in moderate or severe mitral regurgitation secondary to mitral valve prolapse.

PURPOSE: In mitral valve prolapse, determining whether the valve is suitable for surgical repair depends on the location and mechanism of regurgitation. We assessed whether cardiovascular magnetic resonance (CMR) could accurately identify prolapsing or flail mitral valve leaflets and regurgitant jet direction in patients with known moderate or severe mitral regurgitation. METHODS: CMR of the mitral valve was compared with trans-thoracic echocardiography (TTE) in 27 patients with chronic moderate to severe mitral regurgitation due to mitral valve prolapse. Contiguous long-axis high temporal resolution CMR cines perpendicular to the valve commissures were obtained across the mitral valve from the medial to lateral annulus. This technique allowed systematic valve inspection and mapping of leaflet prolapse using a 6 segment model. CMR mapping was compared with trans-oesophageal echocardiography (TOE) or surgical inspection in 10 patients. RESULTS: CMR and TTE agreed on the presence/absence of leaflet abnormality in 53 of 54 (98%) leaflets. Prolapse or flail was seen in 36 of 54 mitral valve leaflets examined on TTE. CMR and TTE agreed on the discrimination of prolapse from flail in 33 of 36 (92%) leaflets and on the predominant regurgitant jet direction in 26 of the 27 (96%) patients. In the 10 patients with TOE or surgical operative findings available, CMR correctly classified presence/absence of segmental abnormality in 49 of 60 (82%) leaflet segments. CONCLUSION: Systematic mitral valve assessment using a simple protocol is feasible and could easily be incorporated into CMR studies in patients with mitral regurgitation due to mitral valve prolapse.