Use of carnosine in the prevention of cardiometabolic risk factors in overweight and obese individuals: study protocol for a randomised, double-blind placebo-controlled trial.

INTRODUCTION: Carnosine, an over the counter food supplement, has been shown to improve glucose metabolism as well as cardiovascular risk factors in animal and human studies through its anti-inflammatory, antioxidative, antiglycating and chelating properties. The aim of this study is to establish if carnosine supplementation improves obesity, insulin sensitivity, insulin secretion, cardiovascular risk factors including arterial stiffness and endothelial function, and other risk factors related to diabetes and cardiovascular disease in the overweight and obese population. METHODS AND ANALYSIS: Fifty participants will be recruited to be enrolled in a double-blind randomised controlled trial. Eligible participants with a body mass index (BMI) between 25 and 40 kg/m2 will be randomly assigned to the intervention or placebo group. Following a medical review and oral glucose tolerance test to check eligibility, participants will then undergo testing. At baseline, participants will have anthropometric measurements (BMI, dual X-ray absorptiometry and peripheral quantitative CT scan), measurements of glucose metabolism (oral glucose tolerance test, intravenous glucose tolerance test and euglycaemic hyperinsulinaemic clamp), cardiovascular measurements (central blood pressure, endothelial function and arterial stiffness), a muscle and fat biopsy, physical activity measurement, liver fibroscan, cognitive function and questionnaires to assess dietary habits, sleep quality, depression, and quality of life. Following baseline assessments, participants will be randomised to either 2 g carnosine or placebo for 15 weeks. In the 15th week, all assessments will be repeated. The preplanned outcome metric is the change between baseline and follow-up measures. ETHICS AND DISSEMINATION: This study is approved by the Human Research Ethics Committee of Monash Health and Monash University, Australia. TRIAL REGISTRATION NUMBER: NCT02686996.

Comparison of diagnostic performance between quantitative flow ratio, non-hyperemic pressure indices and fractional flow reserve.

BACKGROUND: Quantitative flow ratio (QFR) is an estimate of fractional flow reserve (FFR) and is derived from 3-dimensional quantitative coronary angiography. The DILEMMA score is an angiographic technique developed to predict FFR. Unlike other diastolic indices such as instantaneous wave-free ratio (iFR), diastolic pressure ratio (dPR) and dPR25-75, neither QFR nor DILEMMA score require pressure wires. This study sought to compare the diagnostic performance of QFR, diastolic indices and DILEMMA score to predict FFR. METHODS: Between January 2010 and December 2013, patients who underwent invasive coronary angiography and FFR assessments were retrospectively studied. iFR and dPR were derived from FFR pressure tracings. QFR was computed using commercial software. RESULTS: Eighty-five lesions (25% FFR significant) were included in this study. Median FFR was 0.88 (0.81-0.92). QFR (rs=0.801), iFR (rs=0.710), dPR (rs=0.716), dPR25-75 (rs=0.715) and DILEMMA score (rs=-0.623) significantly correlated with FFR (P<0.001). QFR ≤0.8 had a specificity, sensitivity, positive predictive value (PPV) and negative predictive value (NPV) of 95%, 86%, 86% and 95% respectively of predicting significant FFR (P<0.001). Receiver-operating characteristic (ROC) analysis revealed the AUC to predict significant FFR for QFR (0.947), iFR (0.880), dPR (0.883), dPR25-75 (0.880) and DILEMMA score (0.916) were not significantly different. However, QFR was a better predictor of FFR than iFR (0.947 vs. 0.770, P<0.01). CONCLUSIONS: QFR had excellent correlation and accuracy as measured against FFR. When compared to other diastolic indices and DILEMMA score, QFR performed at least as well as the other indices. QFR predicts FFR better than it predicts iFR. QFR is a convenient tool to assess significance of coronary stenosis and a reliable alternative to pressure-wire based indices. Prospective studies are required to investigate the performance and cost-effectiveness of QFR when independently used to guide clinical decision making.

The Natural history of Epicardial Adipose Tissue Volume and Attenuation: A long-term prospective cohort follow-up study.

Epicardial adipose tissue (EAT) is associated with cardiovascular risk. The longitudinal change in EAT volume (EATv) and density (EATd), and potential modulators of these parameters, has not been described. We prospectively recruited 90 patients with non-obstructive coronary atherosclerosis on baseline computed tomography coronary angiography (CTCA) performed for suspected coronary artery disease to undergo a repeat research CTCA. EATv in millilitres (mL) and EATd in Hounsfield units (HU) were analysed and multivariable regression analysis controlling for traditional cardiovascular risk factors (CVRF) performed to assess for any predictors of change. Secondary analysis was performed based on statin therapy. The median duration between CTCA was 4.3years. Mean EATv increased at follow-up (72 ± 33 mL to 89 ± 43 mL, p < 0.001) and mean EATd decreased (baseline -76 ± 6 HU vs. -86 ± 5 HU, p < 0.001). There were no associations between baseline variables of body mass index, age, sex, hypertension, hyperlipidaemia, diabetes or smoking on change in EATv or EATd. No difference in baseline, follow-up or delta EATv or EATd was seen in patients with (60%) or without baseline statin therapy. In this select group of patients, EATv consistently increased and EATd consistently decreased at long-term follow-up and these changes were independent of CVRF, age and statin use. Together with the knowledge of strong associations between EAT and cardiac disease, these findings may suggest that EAT is an independent parameter rather than a surrogate for cardiovascular risk.

Off- vs. On-Pump Coronary Artery Bypass Grafting Long-Term Survival is Driven by Incompleteness of Revascularisation.

BACKGROUND: Off-pump coronary artery bypass grafting (CABG) negates the requirement for extracorporeal circulation used with the traditional on-pump approach. However, off-pump CABG is technically more challenging and may theoretically lead to less complete revascularisation. Recent data suggests a prognostic benefit for traditional on-pump CABG, but the mechanism for this remains unclear. We hypothesised that the inferior outcomes with off-pump CABG could be driven by the need for repeat revascularisation, with this benefit only becoming clear at long-term follow-up. We therefore evaluated short, medium and long-term outcomes of patients undergoing revascularisation with on vs. off-pump CABG. METHODS: Electronic databases were searched to identify suitable randomised controlled trials enrolling ≥100 patients in each arm. Clinical outcomes were extracted at 30-days, 12-months or >4years. The primary outcome was long-term all-cause death, while secondary outcomes included 30-day, 12-month and >4-year cardiac death, stroke, myocardial infarction or revascularisation. RESULTS: Thirteen (13) studies comprising 13,234 patients were included. Off-pump CABG was associated with an increased risk of all-cause death (Odds Ratio [OR] 1.18, 95% confidence interval [CI] 1.02-1.32, p=0.01) and repeat bypass surgery (OR 2.57, 95%CI 1.23-5.39, p=0.01) at long-term follow-up. A significant, increased requirement for revascularisation in off-pump was seen at 12-month follow-up (OR 1.59, 95%CI 1.09-2.33, p=0.02). No differences were noted between groups at 30-days, 12-months and >4years for myocardial infarction or stroke. CONCLUSIONS: Off-pump CABG is associated with significantly higher rates of all-cause mortality rate at long-term follow-up. These outcomes demonstrate a temporal relationship that may be driven by a greater requirement for repeat revascularisation at 1- and 5-year follow-up. STUDY REGISTRATION: CRD42018102019 (PROSPERO).

The utility of coronary computed tomography angiography in elderly patients.

BACKGROUND: Coronary computed tomography angiography (CCTA) is often avoided in elderly patients due to a presumption that a high proportion of patients will have heavily calcified plaque limiting an accurate assessment. We sought to assess the image quality, luminal stenosis and utility of CCTA in elderly patients with suspected coronary artery disease (CAD) and stable chest pain. METHODS: Retrospective analysis of elderly patients (> 75 years) who underwent 320-detector row CCTA between 2012-2017 at MonashHeart. The CCTA was analysed for degree maximal coronary stenosis by CAD-RADS classification, image quality by a 5-point Likert score (1-poor, 2-adequate, 3-good, 4-very good, 5-excellent) and presence of artefact limiting interpretability. RESULTS: 1011 elderly patients (62% females, 78.8 ± 3.3 years) were studied. Cardiovascular risk factor prevalence included: hypertension (65%), hyperlipidaemia (48%), diabetes (19%) and smoking (21%). The CCTA was evaluable in 68% of patients which included 52% with non-obstructive CAD (< 50% stenosis), 48% with obstructive CAD (> 50%) stenosis. Mean Likert score was 3.1 ± 0.6 corresponding to good image quality. Of the 323 (32%) of patients with a non-interpretable CCTA, 80% were due to calcified plaque and 20% due to motion artefact. Male gender (P = 0.009), age (P = 0.02), excess motion (P < 0.01) and diabetes mellitus (P = 0.03) were associated with non-interpretable CCTA. CONCLUSION: Although CCTA is a feasible non-invasive tool for assessment of elderly patients with stable chest pain, clinicians should still be cautious about referring elderly patients for CCTA. Patients who are male, diabetic and >78 years of age are significantly less likely to have interpretable scans.

Non-invasive CT-derived fractional flow reserve and static rest and stress CT myocardial perfusion imaging for detection of haemodynamically significant coronary stenosis.

Computed tomography derived fractional flow reserve (FFRCT) and computed tomography stress myocardial perfusion imaging (CTP) are techniques to assess haemodynamic significance of coronary stenosis. To compare the diagnostic performance of FFRCT and static rest/stress CTP in detecting fractional flow reserve (FFR) defined haemodynamically-significant stenosis (FFR ≤ 0.8). Fifty-one patients (96 vessels) with suspected coronary artery disease from a single institution planned for elective invasive-angiography prospectively underwent research indicated 320-detector-CT-coronary-angiography (CTA) and adenosine-stress CTP and invasive FFR. Analyses were performed in separate core-laboratories for FFRCT and CTP blinded to FFR results. Myocardial perfusion was assessed visually and semi-quantitatively by transmural perfusion ratio (TPR). Invasive FFR ≤ 0.8 was present in 33% of vessels and 49% of patients. FFRCT, visual CTP and TPR analysis was feasible in 96%, 92% and 92% of patients respectively. Overall per-vessel sensitivity, specificity and diagnostic accuracy for FFRCT were 81%, 85%, 84%, for visual CTP were 50%, 89%, 75% and for TPR were 69%, 48%, 56% respectively. Receiver-operating-characteristics curve analysis demonstrated larger per vessel area-under-curve (AUC) for FFRCT (0.89) compared with visual CTP (0.70; p < 0.001), TPR (0.58; p < 0.001) and CTA (0.70; p = 0.0007); AUC for CTA + FFRCT (0.91) was higher than CTA + visual CTP (0.77, p = 0.008) and CTA + TPR (0.74, p < 0.001). Per-patient AUC for FFRCT (0.90) was higher than visual CTP (0.69; p = 0.0016), TPR (0.56; p < 0.0001) and CTA (0.68; p = 0.001). Based on this selected cohort of patients FFRCT is superior to visually and semi-quantitatively assessed static rest/stress CTP in detecting haemodynamically-significant coronary stenosis as determined on invasive FFR.

Familial Hypercholesterolemia With Coexisting Renovascular Stenosis and Premature Coronary Artery Disease.

Familial hypercholesterolemia (FH) is a common hereditary lipid disorder associated with substantial risk of premature atherosclerotic cardiovascular disease. We report an interesting newly diagnosed index case of FH in a 31-year-old man who presented to the hospital with an ST-elevated myocardial infarction. He had a background of inadequately treated hypertension and hypercholesterolemia. Further investigations raised the possibility of secondary hypertension after the identification of renal artery stenosis, in addition to other areas of mesenteric arterial stenoses. Our patient's case highlights that early-onset hypertension and hypercholesterolemia in a young individual may be an early manifestation of FH requiring high clinical vigilance and awareness.

Drug eluting versus bare metal stents for percutaneous coronary intervention of saphenous vein graft lesions: An updated meta-analysis of randomized controlled trials.

BACKGROUND/PURPOSE: Percutaneous coronary intervention (PCI) is the preferred strategy for treatment of saphenous vein graft (SVG) disease. However, there remains ongoing debate on whether drug-eluting stents (DES) or bare-metal stents (BMS) should be used during SVG-PCI. METHODS/MATERIALS: We performed a meta-analysis of randomized controlled trials (RCTs) comparing DES and BMS for SVG-PCI. The primary end point was major adverse cardiac events (MACE), defined as composite of all-cause death, myocardial infarction (MI) or repeat revascularization. Secondary end points included individual MACE components, cardiac death and stent thrombosis (ST). RESULTS: Six RCTs including 1582 patients (50% receiving DES) met inclusion criteria. MACE occurred in 31% (244/797) patients receiving DES and 36% (281/785) patients receiving BMS (median follow-up, 12-35 months). There was no significant difference in MACE between DES and BMS (Odds Ratio (OR) 0.62, 95%CI 0.36-1.09, p = 0.10, I2 = 77%). However, for individual components of MACE, DES was associated with a significant reduction in repeat revascularization (OR 0.53, 95%CI 0.29-0.97, p = 0.04, I2 = 73%). There was no difference in all-cause death (OR 1.30, 95%CI 0.77-2.20, p = 0.33, I2 = 40%), MI (OR 0.68, 95%CI 0.38-1.25, p = 0.22, I2 = 56%), cardiac death (OR 1.08, 95%CI 0.45-2.64, p = 0.86, I2 = 42%) or ST (OR 0.89, 95%CI 0.37-2.17, p = 0.80, I2 = 35%) between stents. CONCLUSIONS: Although there was no significant difference in MACE, DES is associated with a reduction in repeat revascularization compared with BMS in pooled randomized trials for SVG-PCI. The high occurrence of MACE in both stent platforms highlights the need for novel therapeutic approaches to improve clinical outcomes following SVG intervention. SUMMARY: We performed a meta-analysis of randomized controlled trials comparing DES and BMS for SVG-PCI. There was no significant difference in MACE between DES and BMS. However, for individual components of MACE, DES was associated with a significant reduction in repeat revascularization. The high occurrence of MACE in both stent platforms highlights the need for novel therapeutic approaches to improve clinical outcomes following SVG intervention.

Association of Epicardial Adipose Tissue and High-Risk Plaque Characteristics: A Systematic Review and Meta-Analysis.

BACKGROUND: Epicardial adipose tissue (EAT) is hypothesized to alter atherosclerotic plaque composition, with potential development of high-risk plaque (HRP). EAT can be measured by volumetric assessment (EAT-v) or linear thickness (EAT-t). We performed a systematic review and random-effects meta-analysis to assess the association of EAT with HRP and whether this association is dependent on the measurement method used. METHODS AND RESULTS: Electronic databases were systematically searched up to October 2016. Studies reporting HRP by computed tomography or intracoronary imaging and studies measuring EAT-v or EAT-t were included. Odds ratios were extracted from multivariable models reporting the association of EAT with HRP and described as pooled estimates with 95% confidence intervals (CIs). Analysis was stratified by EAT measurement method. Nine studies (n=3772 patients) were included with 7 measuring EAT-v and 2 measuring EAT-t. Increasing EAT was significantly associated with the presence of HRP (odds ratio: 1.26 [95% CI, 1.11-1.43]; P<0.001). Patients with HRP had higher EAT-v than those without (weighted mean difference: 28.3 mL [95% CI, 18.8-37.8 mL]; P<0.001). EAT-v was associated with HRP (odds ratio: 1.19 [95% CI, 1.06-1.33]; P<0.001); however, EAT-t was not (odds ratio: 3.09 [95% CI, 0.56-17]; P=0.2). Estimates remained significant when adjusted for small-study effect bias (odds ratio: 1.13 [95% CI, 1.03-1.28]; P=0.04). CONCLUSIONS: Increasing EAT is associated with the presence of HRP, and patients with HRP have higher quantified EAT-v. The association of EAT-v with HRP is significant compared with EAT-t; however, a larger scale study is still required, and further evaluation is needed to assess whether EAT may be a potential therapeutic target for novel pharmaceutical agents. CLINICAL TRIAL REGISTRATION: URL: https://www.crd.york.ac.uk/. Unique identifier: CRD42017055473.

Optical Coherence Tomography Guided Percutaneous Coronary Intervention.

Optical coherence tomography (OCT) is an increasingly available intracoronary imaging modality that provides high-resolution imaging of coronary arteries. Its fundamental reliance on the emission and reflection of light enables rapid data acquisition without compromise of image resolution. As such, OCT can inform operators planning percutaneous coronary intervention (PCI) by accurately defining luminal geometry and detailing plaque composition. Following PCI, OCT imaging delivers a thorough assessment of the treated arterial segment and can identify specific features not always visible on alternate imaging modalities, including stent edge-related dissection, plaque tissue prolapse, incomplete stent apposition and the presence of intra-coronary thrombus. Clinical trials highlight that procedural strategy is frequently altered based on OCT findings, while concerns over final stent dimensions have been mitigated through use of a sizing protocol based on external elastic lamina dimensions in the reference arterial segment. Randomised trials are now warranted to definitively ascertain whether OCT-guidance improves clinical outcomes when utilised during PCI.

Impact of heart rate on diagnostic accuracy of second generation 320-detector computed tomography coronary angiography.

OBJECTIVE: To assess the impact of elevated heart rate (HR) on the diagnostic accuracy and image quality of second-generation 320-detector computed tomography coronary angiography (320-CTCA). METHODS: Consecutive patients with suspected coronary disease referred for invasive coronary angiography (ICA) were prospectively recruited and underwent 320-CTCA. Pre-scan beta-blockers were administered if native HR>80 bpm and post-scan cohorts stratified by traditional (HR ≤60 bpm) and elevated HR (61-80 bpm). A wider phase window was used for the elevated HR group (30-80%). 320-CTCA and ICA were analyzed by independent readers blinded to other data. Significant disease was defined as ≥50% visual stenosis on ICA. Uninterpretable segments by 320-CTCA were considered to be significant on an intention-to-diagnose principle. Image quality was assessed by 5-point Likert score. RESULTS: Of 107 patients studied (1,662 segments), there was no significant difference in sensitivity, specificity, positive and negative predictive value between patients with HR ≤60 bpm (n=55) vs. HR 61-80 bpm (n=52): 97%, 88%, 95%, 94% vs. 100%, 88%, 95%, 100%; Receiver operator characteristic-area under the curve 0.93 vs. 0.94, P=0.82). Overall per-patient diagnostic accuracy was 96% in both groups with no significant difference in interpretable segments (Likert ≥2) or median radiation dose (2.4 mSv vs. 2.7 mSv, P=0.35). Only 4/1,662 (0.2%) segments were uninterpretable by motion artefact in the whole cohort. CONCLUSIONS: In patients with HR >60 and up to 80bpm, second generation 320-CTCA provides comparably adequate diagnostic accuracy to HR ≤60 without significantly impacting upon overall segmental evaluability.

Epicardial adipose tissue and myocardial ischemia assessed by computed tomography perfusion imaging and invasive fractional flow reserve.

BACKGROUND: Epicardial adipose tissue (EAT) is a metabolically active fat depot that is associated with incident coronary artery disease (CAD) and major adverse cardiovascular events. The relationship between EAT and myocardial ischemia remains unclear. This study investigated the relationship between EAT volume and the presence of perfusion defects on myocardial computed tomographic perfusion imaging (CTP) and functional stenoses on invasive fractional flow-reserve (FFR). METHODS: Data were obtained from a previous prospective cross-sectional study in patients with suspected CAD. Patients underwent combined coronary computed tomography angiography (coronary CTA) and CTP followed by invasive coronary angiogram (ICA) and FFR within 14 days. FFR was performed in all major epicardial vessels unless they were angiographically smooth or occluded, with a threshold of <0.8 considered significant. EAT volume was quantified semi-automatically on coronary CTA. RESULTS: There were 38 patients included for analysis, mean age 62.5 ± 10.0 years, 68.4% male. Median EAT volume was 82.8 mL (interquartile range (IQR) 49.3 mL). FFR was interrogated in 73/114 (64%) vessels. There was no difference in EAT volumes in patients with and without CTP defects (84.4 mL, IQR: 35.6 mL vs 81.1 mL, IQR: 53.1 mL, p = 0.7). There was also no difference in EAT volumes in patients with and without FFR-significant vessels (86.5 mL IQR: 36.6 mL vs 79.1 mL IQR: 54.5 mL, p = 0.7) and no difference when analysed by number of CTP positive territories or FFR-significant vessels (p = 0.4 and p = 0.8 respectively). CONCLUSION: This study demonstrated no observable relationship between EAT volume and perfusion defects on myocardial CT perfusion imaging or functional stenosis on invasive FFR.

Percutaneous Coronary Intervention Using Drug-Eluting Stents Versus Coronary Artery Bypass Grafting for Unprotected Left Main Coronary Artery Stenosis: A Meta-Analysis of Randomized Trials.

BACKGROUND: Current guidelines suggest that coronary artery bypass grafting (CABG) should be the preferred revascularization method for unprotected left main coronary artery stenosis. In light of evidence from recent randomized trials, we assessed whether percutaneous coronary intervention (PCI) using drug-eluting stents is as safe and effective as CABG for the treatment of unprotected left main coronary artery disease. METHODS AND RESULTS: Digital databases and manual searches were performed for randomized trials comparing PCI and CABG for unprotected left main coronary artery stenosis. Among 3887 potentially relevant studies, 5 met inclusion criteria. The primary safety end point was defined as the composite of all-cause death, myocardial infarction, or stroke. Secondary end points included a clinical effectiveness composite, which was defined as all-cause death, myocardial infarction, stroke, or repeat revascularization. Summary estimates were obtained using random-effects modeling. In total, 4594 patients were included in the analysis. There was no significant difference in the primary safety end point between the revascularization strategies (odds ratio [OR], 0.97; 95% confidence interval [CI], 0.79-1.17; P=0.73). However, when compared with CABG, PCI was less effective (OR, 1.36; 95% CI, 1.18-1.58; P<0.001) because of significantly higher rates of repeat revascularization (OR, 1.85; 95% CI, 1.53-2.23; P<0.001). The incidence of all-cause death (OR, 1.03; 95% CI, 0.78-1.35; P=0.61), myocardial infarction (OR, 1.46; 95% CI, 0.88-2.45; P=0.08), and stroke (OR, 0.88; 95% CI, 0.39-1.97; P=0.53) did not differ between PCI and CABG. CONCLUSIONS: PCI using drug-eluting stents and CABG are equally safe methods of revascularization for patients at low surgical risk with significant unprotected left main coronary artery stenosis. However, CABG is associated with significantly lower rates of repeat revascularization.

Percutaneous Coronary Intervention Enhances Accelerative Wave Intensity in Coronary Arteries.

BACKGROUND: The systolic forward travelling compression wave (sFCW) and diastolic backward travelling decompression waves (dBEW) predominantly accelerate coronary blood flow. The effect of a coronary stenosis on the intensity of these waves in the distal vessel is unknown. We investigated the relationship between established physiological indices of hyperemic coronary flow and the intensity of the two major accelerative coronary waves identified by Coronary Wave Intensity analysis (CWIA). METHODOLOGY / PRINCIPAL FINDINGS: Simultaneous intracoronary pressure and velocity measurement was performed during adenosine induced hyperemia in 17 patients with pressure / Doppler flow wires positioned distal to the target lesion. CWI profiles were generated from this data. Fractional Flow Reserve (FFR) and Coronary Flow Velocity Reserve (CFVR) were calculated concurrently. The intensity of the dBEW was significantly correlated with FFR (R = -0.70, P = 0.003) and CFVR (R = -0.73, P = 0.001). The intensity of the sFCW was also significantly correlated with baseline FFR (R = 0.71, p = 0.002) and CFVR (R = 0.59, P = 0.01). Stenting of the target lesion resulted in a median 178% (interquartile range 55-280%) (P<0.0001) increase in sFCW intensity and a median 117% (interquartile range 27-509%) (P = 0.001) increase in dBEW intensity. The increase in accelerative wave intensity following PCI was proportionate to the baseline FFR and CFVR, such that stenting of lesions associated with the greatest flow limitation (lowest FFR and CFVR) resulted in the largest increases in wave intensity. CONCLUSIONS: Increasing ischemia severity is associated with proportionate reductions in cumulative intensity of both major accelerative coronary waves. Impaired diastolic microvascular decompression may represent a novel, important pathophysiologic mechanism driving the reduction in coronary blood flow in the setting of an epicardial stenosis.

Anatomic characteristics and outcome of adults with coronary arteries arising from an anomalous location detected with coronary computed tomography angiography.

We sought to determine the anatomic characteristics of coronary arteries arising from an anomalous location (CAAL) detected on coronary computed tomography angiography (CTA) and assess the impact of high-risk anatomic characteristics on patient management and outcomes. We reviewed 9,774 consecutive CTA studies performed in adults between 2008-2013 and identified 114 with CAAL. CTA examinations were analysed to determine CAAL type, CAAL course (pre-pulmonary, interarterial, septal or retroaortic) and whether additional high-risk anatomic characteristics were present (luminal compression, intramural course, slit-like ostium and acute takeoff angle). Patients were contacted at mean 27.1-months to determine safety outcomes. The prevalence of CAAL was 1.14 % (114 of 9,974), with 36 (32 %) having anomalous right coronary artery from left coronary sinus, 71 (62 %) having anomalous left coronary artery from right coronary sinus and 7 (6 %) having a coronary artery arising outside coronary sinuses. Fifty-six patients (49 %) had ≥1 high-risk anatomic characteristic on CTA. Ten patients (9 %) underwent surgical intervention. Patients with high-risk anatomic features more frequently underwent functional testing (46 vs. 12 %, P = 0.01) and surgical intervention (14 vs. 3 %; P = 0.04) compared to patients without high-risk features. Patients undergoing surgery were more likely to have obstructive coronary disease on CTA than patients managed conservatively (50 vs. 13 %, P = 0.01). There was no cardiac death or ACS at follow-up (100 % complete). High-risk anatomic features on CTA in patients with CAAL more frequently lead to surgical management. Regardless of CAAL type, presence of high-risk anatomic characteristics or management strategy, the medium-term outcome of adults with CAAL is excellent.

Superior CT coronary angiography image quality at lower radiation exposure with second generation 320-detector row CT in patients with elevated heart rate: a comparison with first generation 320-detector row CT.

BACKGROUND: This study aims to compare the image quality of second generation versus first generation 320-computed tomography coronary angiography (CTCA) in patients with heart rate ≥65 bpm as it has not been specifically reported. METHODS: Consecutive patients who underwent CTCA using second-generation-320-detector-row-CT were prospectively enrolled. A total of 50 patients with elevated (≥65 bpm) heart rate and 50 patients with controlled (<65 bpm) heart rate were included. Age and gender matched patients who were scanned with the first-generation-320-detector-row-CT were retrospectively identified. Image quality in each coronary artery segment was assessed by two blinded CT angiographers using the five-point Likert scale. RESULTS: In the elevated heart rate cohorts, while there was no significant difference in heart rate during scan-acquisition (66 vs. 69 bpm, P=0.308), or body mass index (28.5 vs. 29.6, P=0.464), the second generation scanner was associated with better image quality (3.94±0.6 vs. 3.45±0.8, P=0.001), and with lower radiation (2.8 vs. 4.3 mSv, P=0.009). There was no difference in scan image quality for the controlled heart rate cohorts. CONCLUSIONS: The second generation CT scanner provides better image quality at lower radiation dose in patients with elevated heart rate (≥65 bpm) compared to first generation CT scanner.