Prevalence and outcome of dual aortic stenosis and cardiac amyloid pathology in patients referred for transcatheter aortic valve implantation.

AIMS: Cardiac amyloidosis is common in elderly patients with aortic stenosis (AS) referred for transcatheter aortic valve implantation (TAVI). We hypothesized that patients with dual aortic stenosis and cardiac amyloid pathology (AS-amyloid) would have different baseline characteristics, periprocedural and mortality outcomes. METHODS AND RESULTS: Patients aged ≥75 with severe AS referred for TAVI at two sites underwent blinded bone scintigraphy prior to intervention (Perugini Grade 0 negative, 1-3 increasingly positive). Baseline assessment included echocardiography, electrocardiogram (ECG), blood tests, 6-min walk test, and health questionnaire, with periprocedural complications and mortality follow-up. Two hundred patients were recruited (aged 85 ± 5 years, 50% male). AS-amyloid was found in 26 (13%): 8 Grade 1, 18 Grade 2. AS-amyloid patients were older (88 ± 5 vs. 85 ± 5 years, P = 0.001), with reduced quality of life (EQ-5D-5L 50 vs. 65, P = 0.04). Left ventricular wall thickness was higher (14 mm vs. 13 mm, P = 0.02), ECG voltages lower (Sokolow-Lyon 1.9 ± 0.7 vs. 2.5 ± 0.9 mV, P = 0.03) with lower voltage/mass ratio (0.017 vs. 0.025 mV/g/m2, P = 0.03). High-sensitivity troponin T and N-terminal pro-brain natriuretic peptide were higher (41 vs. 21 ng/L, P < 0.001; 3702 vs. 1254 ng/L, P = 0.001). Gender, comorbidities, 6-min walk distance, AS severity, prevalence of disproportionate hypertrophy, and post-TAVI complication rates (38% vs. 35%, P = 0.82) were the same. At a median follow-up of 19 (10-27) months, there was no mortality difference (P = 0.71). Transcatheter aortic valve implantation significantly improved outcome in the overall population (P < 0.001) and in those with AS-amyloid (P = 0.03). CONCLUSIONS: AS-amyloid is common and differs from lone AS. Transcatheter aortic valve implantation significantly improved outcome in AS-amyloid, while periprocedural complications and mortality were similar to lone AS, suggesting that TAVI should not be denied to patients with AS-amyloid.

Transcatheter aortic valve implantation in acute decompensated aortic stenosis.

OBJECTIVES: To assess the safety and efficacy of first-line transcatheter aortic valve implantation (TAVI) in patients presenting with acute decompensated aortic stenosis (ADAS). BACKGROUND: ADAS is common and is often treated medically or using balloon aortic valvuloplasty in the first instance. This temporizing measure results in suboptimal outcomes. In the current era, TAVI provides an alternative option. METHODS: Consecutive patients who had either a TAVI for ADAS or electively were included in the study. The primary outcome was procedural and 30-day mortality and hospital length of stay (LOS). Secondary outcomes included 1-year mortality and procedural complications. RESULTS: Of note, 893 patients (mean age 83 ± 7, 50.5% male) underwent TAVI (19% ADAS, 81% elective). ADAS patients were more unwell with worse echocardiographic parameters than elective patients. ADAS patients of 55.9% were known to have significant aortic stenosis prior to their decompensation. Procedural mortality was not different between the ADAS and elective cohorts (1.2 vs. 0.7%; p = .62). The ADAS cohort had a higher 30-day mortality (5.3 vs. 1.1%; p = .002) and longer LOS (31.9 ± 20.7 days vs. 6.1 ± 6.5 days; p < .001). Multivariate analysis identified acute kidney injury and ADAS as significant predictors of 30-day mortality. CONCLUSIONS: TAVI for ADAS is safe and effective with procedural outcomes similar to elective patients. However, compared to elective patients, they have worse physiological baseline features, poorer prognosis at 30 days, and longer hospital admissions. Majority of patients who presented with ADAS were known to have AS prior to admission.

Patterns of solid particle embolization during transcatheter aortic valve implantation and correlation with aortic valve calcification.

OBJECTIVES: To evaluate solid embolization during transcatheter aortic valve implantation (TAVI) and correlate this with aortic valve calcification. BACKGROUND: There is a known stroke risk with TAVI, thought partly to be due to dislodgement of native aortic valve particles during implantation. However, to date there is little evidence that aortic valve calcification actually impacts embolic risk. METHODS: Transcranial Doppler (TCD) was performed on consecutive suitable patients undergoing TAVI, using hardware and software enabling differentiation between solid and gaseous emboli. Data was analyzed by time points during the TAVI procedure. These results were correlated with aortic valve calcification. RESULTS: TCD was successfully performed on 63 patients. The median number of solid emboli was 76.0. The most common time point for solid embolization was during valve positioning. Forty-five of these patients had an appropriate CT scan which could be analyzed for an Agatston calcium score. The mean scores in the aortic valve and aortic root were 3382.4 and 754.9. There were significant correlations between the total number of solid emboli and valve calcium score (P = 0.033) and solid emboli during valve positioning and valve calcium score (P = 0.035). There was no relationship between gaseous emboli and valve calcium score. CONCLUSIONS: TAVI is associated with significant solid particle embolization, with the most common time point being during valve positioning. Solid embolization correlates with aortic valve calcium score, suggesting that valve calcification is a factor in embolic risk. This should be taken into consideration along with other clinical factors when assessing embolic risk.

Balloon-Expandable Transcatheter Aortic Valves Can Be Successfully and Safely Implanted Transfemorally Without Balloon Valvuloplasty.

OBJECTIVES: To assess the necessity for balloon aortic valvuloplasty (BAV) during transfemoral transcatheter aortic valve implantation (TAVI) when using balloon-expandable valves. BACKGROUND: BAV is a usual part of TAVI procedures, prior to valve implantation. However, the benefits and necessity of this are unknown and recent evidence in self-expanding valves suggests it may not be necessary. METHODS: Retrospective single-center study of 154 patients undergoing first-time, transfemoral TAVI for native aortic valve stenosis, with (N = 76), and without (N = 78), BAV as part of the procedure. Data collected included demographic, procedural, and outcome data. RESULTS: BAV did not alter VARC-2 defined procedural success or early safety compared to not performing a BAV, including mortality, degree of aortic regurgitation, or need for post-TAVI balloon dilatation, although there was a strong trend to reduced stroke when not performing a BAV. There was a significantly reduced procedural time (P = 0.01) and fluoroscopic time (P < 0.001) without performing a BAV. There were no differences in cerebral embolization (solid, gaseous, or total emboli) noted between the 2 groups, as measured on transcranial doppler (TCD). CONCLUSIONS: TAVI can be effectively and safely performed without a BAV and this results in reduced procedural and fluoroscopic times, although embolization to the brain is not reduced. There is a trend toward reduced stroke risk. (J Interven Cardiol 2016;29:319-324).

Differences in vascular nitric oxide and endothelium-derived hyperpolarizing factor bioavailability in blacks and whites.

OBJECTIVE: Abnormalities in nitric oxide (NO) bioavailability have been reported in blacks. Whether there are differences in endothelium-derived hyperpolarizing factor (EDHF) in addition to NO between blacks and whites and how these affect physiological vasodilation remain unknown. We hypothesized that the bioavailability of vascular NO and EDHF, at rest and with pharmacological and physiological vasodilation, varies between whites and blacks. APPROACH AND RESULTS: In 74 white and 86 black subjects without known cardiovascular disease risk factors, forearm blood flow was measured using plethysmography at rest and during inhibition of NO with N(G)-monomethyl-L-arginine and of K(+) Ca channels (EDHF) with tetraethylammonium. The reduction in resting forearm blood flow was greater with N(G)-monomethyl-L-arginine (P=0.019) and similar with tetraethylammonium in whites compared with blacks. Vasodilation with bradykinin, acetylcholine, and sodium nitroprusside was lower in blacks compared with whites (all P<0.0001). Inhibition with N(G)-monomethyl-L-arginine was greater in whites compared with blacks with bradykinin, acetylcholine, and exercise. Inhibition with tetraethylammonium was lower in blacks with bradykinin, but greater during exercise and with acetylcholine. CONCLUSIONS: The contribution to both resting and stimulus-mediated vasodilator tone of NO is greater in whites compared with blacks. EDHF partly compensates for the reduced NO release in exercise and acetylcholine-mediated vasodilation in blacks. Preserved EDHF but reduced NO bioavailability and sensitivity characterizes the vasculature in healthy blacks. CLINICAL TRIAL REGISTRATION URL: http://clinicaltrials.gov/. Unique identifier: NCT00166166.

Contribution of endothelium-derived hyperpolarizing factor to exercise-induced vasodilation in health and hypercholesterolemia.

The role of endothelium-derived hyperpolarizing factor (EDHF) in either the healthy circulation or in those with hypercholesterolemia is unknown. In healthy and hypercholesterolemic subjects, we measured forearm blood flow (FBF) using strain-gauge plethysmography at rest, during graded handgrip exercise, and after sodium nitroprusside infusion. Measurements were repeated after l-NMMA, tetraethylammonium (TEA), and combined infusions. At rest, l-NMMA infusion reduced FBF in healthy but not hypercholesterolemic subjects. At peak exercise, vasodilation was lower in hypercholesterolemic compared to healthy subjects (274% vs 438% increase in FBF, p=0.017). TEA infusion reduced exercise-induced vasodilation in both healthy and hypercholesterolemic subjects (27%, p<0.0001 and -20%, p<0.0001, respectively). The addition of l-NMMA to TEA further reduced FBF in healthy (-14%, p=0.012) but not in hypercholesterolemic subjects, indicating a reduced nitric oxide and greater EDHF-mediated contribution to exercise-induced vasodilation in hypercholesterolemia. In conclusion, exercise-induced vasodilation is impaired and predominantly mediated by EDHF in hypercholesterolemic subjects. CLINICAL TRIAL REGISTRATION IDENTIFIER NCT00166166:

Endothelium-derived hyperpolarizing factor mediates bradykinin-stimulated tissue plasminogen activator release in humans.

AIMS: Bradykinin (BK) stimulates tissue plasminogen activator (t-PA) release from human endothelium. Although BK stimulates both nitric oxide and endothelium-derived hyperpolarizing factor (EDHF) release, the role of EDHF in t-PA release remains unexplored. This study sought to determine the mechanisms of BK-stimulated t-PA release in the forearm vasculature of healthy human subjects. METHODS: In 33 healthy subjects (age 40.3 ± 1.9 years), forearm blood flow (FBF) and t-PA release were measured at rest and after intra-arterial infusions of BK (400 ng/min) and sodium nitroprusside (3.2 mg/min). Measurements were repeated after intra-arterial infusion of tetraethylammonium chloride (TEA; 1 µmol/min), fluconazole (0.4 µmol·min(-1)·l(-1)), and N(G)-monomethyl-L-arginine (L-NMMA, 8 µmol/min) to block nitric oxide, and their combination in separate studies. RESULTS: BK significantly increased net t-PA release across the forearm (p < 0.0001). Fluconazole attenuated both BK-mediated vasodilation (-23.3 ± 2.7% FBF, p < 0.0001) and t-PA release (from 50.9 ± 9.0 to 21.3 ± 8.9 ng/min/100 ml, p = 0.02). TEA attenuated FBF (-14.7 ± 3.2%, p = 0.002) and abolished BK-stimulated t-PA release (from 22.9 ± 5.7 to -0.8 ± 3.6 ng/min/100 ml, p = 0.0002). L-NMMA attenuated FBF (p < 0.0001), but did not inhibit BK-induced t-PA release (nonsignificant). CONCLUSION: BK-stimulated t-PA release is partly due to cytochrome P450-derived epoxides and is inhibited by K(+)Ca channel blockade. Thus, BK stimulates both EDHF-dependent vasodilation and t-PA release.

Thrombus Burden and Outcomes in Patients With COVID-19 Presenting With STEMI Across the Pandemic.

BACKGROUND: It has been previously reported during the first COVID-19 outbreak that patients presenting with ST-segment elevation myocardial infarction (STEMI) and concurrent COVID-19 infection have increased thrombus burden and poorer outcomes. To date, there have been no reports comparing the outcomes of COVID-19-positive STEMI patients across all waves of the pandemic. OBJECTIVES: This study compared the baseline demographic, procedural, and angiographic characteristics alongside the clinical outcomes of patients presenting with STEMI and concurrent COVID-19 infection across the COVID-19 pandemic in the United Kingdom. METHODS: This was a single-center, observational study of 1,269 consecutive patients admitted with confirmed STEMI treated with percutaneous coronary intervention (between January 3, 2020 and October 3, 2022). COVID-19-positive patients were split into 3 groups based upon the time course of the pandemic, and a comparison was made between waves. RESULTS: A total of 154 COVID-19-positive patients with STEMI were included in the present analysis and were compared with 1,115 COVID-19-negative patients. Early during the pandemic (wave 1), STEMI patients presenting with concurrent COVID-19 infection had high rates of cardiac arrest, evidence of increased thrombus burden, bigger infarcts, and worse outcomes. However, by wave 3, no differences existed in outcomes between COVID-19-positive and -negative patients, with significant differences compared with earlier COVID-19-positive patients. Poor outcomes later in the study period were predominantly in unvaccinated individuals. CONCLUSIONS: Significant changes have occurred in the clinical characteristics, angiographic features, and outcomes of STEMI patients with COVID-19 infection treated by primary percutaneous coronary intervention during the course of the pandemic. Importantly, outcomes of recent waves and in vaccinated individuals are no different to a non-COVID-19 population.

An exploration of the early discharge approach for low-risk STEMI patients following primary percutaneous coronary intervention.

Recently, there has been growing interest in the early discharge strategy for low-risk patients who have undergone primary percutaneous coronary intervention (PCI) to treat ST-segment elevation myocardial infarction (STEMI). So far findings have suggested there are multiple advantages of shorter hospital stays, including that it could be a safe way to be more cost- and resource-efficient, reduce cases of hospital-acquired infection and boost patient satisfaction. However, there are remaining concerns surrounding safety, patient education, adequate follow-up and the generalisability of the findings from current studies which are mostly small-scale. By assessing the current research, we describe the advantages, disadvantages and challenges of early hospital discharge for STEMI and discuss the factors that determine if a patient can be considered low risk. If it is feasible to safely employ a strategy like this, the implications for healthcare systems worldwide could be extremely beneficial, particularly in lower-income economies and when we consider the detrimental impacts of the recent COVID-19 pandemic on healthcare systems.

Endothelium-derived hyperpolarizing factor determines resting and stimulated forearm vasodilator tone in health and in disease.

BACKGROUND: We assessed the contribution of endothelium-derived hyperpolarizing factors to resting and agonist-stimulated vasodilator tone in health and disease. Tetraethylammonium chloride (TEA) was used to inhibit K(+)(Ca) channel activation and fluconazole was used to inhibit cytochrome P450 2C9-mediated epoxyeicosatrienoic acid synthesis. We hypothesized that endothelium-derived hyperpolarizing factors contribute to resting vascular tone by K(+)(Ca) channel activation and epoxyeicosatrienoic acid release and that endothelium-derived hyperpolarizing factors compensate for reduced nitric oxide bioavailability at rest and with endothelium-dependent vasodilators. METHODS AND RESULTS: In 103 healthy subjects and 71 nonhypertensive subjects with multiple risk factors, we measured resting forearm blood flow (FBF) using venous occlusion plethysmography before and after intra-arterial infusions of N(G)-monomethyl-l-arginine (L-NMMA), TEA, fluconazole, and their combination. The effects of these antagonists on resting FBF and on bradykinin- and acetylcholine-mediated vasodilation were studied. Resting FBF decreased with TEA and L-NMMA in all subjects (P<0.001); however, the vasoconstrictor response to L-NMMA was greater (P=0.04) and to TEA was lower (P=0.04) in healthy subjects compared with those with risk factors. Fluconazole decreased resting FBF in all subjects, and the addition of TEA further reduced FBF after fluconazole, suggesting that cytochrome P450 metabolites and other hyperpolarizing factor(s) activate K(+)(Ca) channels. Both L-NMMA and TEA attenuated bradykinin-mediated vasodilation in healthy and hypercholesterolemic subjects (P<0.001). In contrast, acetylcholine-mediated vasodilation remained unchanged with TEA in healthy subjects but was significantly attenuated in hypercholesterolemia (P<0.04). CONCLUSIONS: First, by activating TEA-inhibitable K(+)(Ca) channels, endothelium-derived hyperpolarizing factors, together with nitric oxide, contribute to resting microvascular dilator tone. The contribution of K(+)(Ca) channel activation compared with nitric oxide is greater in those with multiple risk factors compared with healthy subjects. Second, activation of K(+)(Ca) channels is only partly through epoxyeicosatrienoic acid release, indicating the presence of other hyperpolarizing mechanisms. Third, bradykinin, but not acetylcholine, stimulates K(+)(Ca) channel-mediated vasodilation in healthy subjects, whereas in hypercholesterolemia, K(+)(Ca) channel-mediated vasodilation compensates for the reduced nitric oxide activity. Thus, enhanced endothelium-derived hyperpolarizing factor activity in conditions of nitric oxide deficiency contributes to maintenance of resting and agonist-stimulated vasodilation. Clinical Trial Registration- URL: http://www.clinicaltrials.gov. Unique identifier: NCT00166166.

Minimising permanent pacemaker implantation (PPI) after TAVI.

Increased demand for transcatheter aortic valve implantation (TAVI) procedures for patients with severe aortic stenosis has not been matched with a proportional increase in available resources in recent years. This article highlights the importance of developing integrated care pathways for TAVI, which incorporate standardised protocols for permanent pacemaker implantation (PPI) to ensure best practice, increase service efficiency and reduce rates of PPI post-TAVI.

Validation of the CREST score for predicting circulatory-aetiology death in out-of-hospital cardiac arrest without STEMI.

AIMS: The CREST tool was recently developed to stratify the risk of circulatory-aetiology death (CED) in out-of-hospital cardiac arrest (OHCA) patients without ST-elevation myocardial infarction (STEMI). We aimed to validate the CREST score using an external cohort and determine whether it could be improved by the addition of serum lactate on admission. METHODS: The study involved the retrospective analysis of consecutive patients admitted to a single tertiary centre with OHCA of presumed cardiac origin over a 51-month period. The CREST score was calculated by attributing points to the following variables: Coronary artery disease (CAD), non-shockable Rhythm, Ejection fraction <30%, cardiogenic Shock at presentation and ischaemic Time ≥25 minutes. The primary endpoint was CED vs neurological aetiology death (NED) or survival. RESULTS: Of 500 patients admitted with OHCA, 211 did not meet criteria for STEMI and were included. 115 patients died in hospital (71 NED, 44 CED). When analysed individually, CED was associated with all CREST variables other than a previous diagnosis of CAD. The CREST score accurately predicted CED with excellent discrimination (C-statistic 0.880, 95% CI 0.813-0.946) and calibration (Hosmer and Lemeshow P=0.948). Although an admission lactate ≥7 mmol/L also predicted CED, its addition to the CREST score (the C-AREST score) did not significantly improve the predictive ability (CS 0.885, 0.815-0.954, HS P=0.942, X2 difference in -2 log likelihood =0.326, P=0.850). CONCLUSION: Our study is the first to independently validate the CREST score for predicting CED in patients presenting with OHCA without STEMI. Addition of lactate on admission did not improve its predictive ability.

Prevalence and Outcomes of Concomitant Aortic Stenosis and Cardiac Amyloidosis.

BACKGROUND: Older patients with severe aortic stenosis (AS) are increasingly identified as having cardiac amyloidosis (CA). It is unknown whether concomitant AS-CA has worse outcomes or results in futility of transcatheter aortic valve replacement (TAVR). OBJECTIVES: This study identified clinical characteristics and outcomes of AS-CA compared with lone AS. METHODS: Patients who were referred for TAVR at 3 international sites underwent blinded research core laboratory 99mtechnetium-3,3-diphosphono-1,2-propanodicarboxylic acid (DPD) bone scintigraphy (Perugini grade 0: negative; grades 1 to 3: increasingly positive) before intervention. Transthyretin-CA (ATTR) was diagnosed by DPD and absence of a clonal immunoglobulin, and light-chain CA (AL) was diagnosed via tissue biopsy. National registries captured all-cause mortality. RESULTS: A total of 407 patients (age 83.4 ± 6.5 years; 49.8% men) were recruited. DPD was positive in 48 patients (11.8%; grade 1: 3.9% [n = 16]; grade 2/3: 7.9% [n = 32]). AL was diagnosed in 1 patient with grade 1. Patients with grade 2/3 had worse functional capacity, biomarkers (N-terminal pro-brain natriuretic peptide and/or high-sensitivity troponin T), and biventricular remodeling. A clinical score (RAISE) that used left ventricular remodeling (hypertrophy/diastolic dysfunction), age, injury (high-sensitivity troponin T), systemic involvement, and electrical abnormalities (right bundle branch block/low voltages) was developed to predict the presence of AS-CA (area under the curve: 0.86; 95% confidence interval: 0.78 to 0.94; p < 0.001). Decisions by the heart team (DPD-blinded) resulted in TAVR (333 [81.6%]), surgical AVR (10 [2.5%]), or medical management (65 [15.9%]). After a median of 1.7 years, 23% of patients died. One-year mortality was worse in all patients with AS-CA (grade: 1 to 3) than those with lone AS (24.5% vs. 13.9%; p = 0.05). TAVR improved survival versus medical management; AS-CA survival post-TAVR did not differ from lone AS (p = 0.36). CONCLUSIONS: Concomitant pathology of AS-CA is common in older patients with AS and can be predicted clinically. AS-CA has worse clinical presentation and a trend toward worse prognosis, unless treated. Therefore, TAVR should not be withheld in AS-CA.

An observational study assessing the impact of a cardiac arrest centre on patient outcomes after out-of-hospital cardiac arrest (OHCA).

BACKGROUND: Out-of-hospital cardiac arrest (OHCA) is a major cause of death worldwide. Recent guidelines recommend the centralisation of OHCA services in cardiac arrest centres to improve outcomes. In 2015, two major tertiary cardiac centres in London merged to form a large dedicated tertiary cardiac centre. This study aimed to compare the short-term mortality of patients admitted with an OHCA before-and-after the merger of services had taken place and admission criteria were relaxed, which led to managing OHCA in higher volume. METHODS: We retrospectively analysed the data of OHCA patients pre- and post-merger. Baseline demographic and medical characteristics were recorded, along with factors relating to the cardiac arrest. The primary endpoint was in-hospital mortality. RESULTS: OHCA patients (N =728; 267 pre- and 461 post-merger) between 2013 and 2018 were analysed. Patients admitted pre-merger were older (65.0 vs. 62.4 years, p=0.027), otherwise there were similar baseline demographic and peri-arrest characteristics. There was a greater proportion of non-acute coronary syndrome-related OHCA admission post-merger (10.1% vs. 23.4%, p=0.0001) and a corresponding decrease in those admitted with ST-elevation myocardial infarction (80.2% vs. 57.0%, p=0.0001) and those treated with percutaneous coronary intervention (78.8% vs. 54.0%, p=0.0001). Despite this, in-hospital mortality was lower post-merger (63.7% vs. 44.3%, p=0.0001), which persisted after adjustment for demographic and arrest-related characteristics using stepwise logistic regression (p=0.036) between the groups. CONCLUSION: Despite an increase in non-acute coronary syndrome-related OHCA cases, the formation of a centralised invasive heart centre was associated with improved survival in OHCA patients. This suggests there may be a benefit of a cardiac arrest centre model of care.

Optical coherence tomography enables more accurate detection of functionally significant intermediate non-left main coronary artery stenoses than intravascular ultrasound: A meta-analysis of 6919 patients and 7537 lesions.

OBJECTIVE: Fractional flow reserve (FFR) is regarded as the gold standard for the physiological assessment of intermediate coronary artery stenoses. However, FFR does not allow assessment of plaque morphology and lesion geometry. Intracoronary imaging techniques such as intravascular ultrasound (IVUS) and optical coherence tomography (OCT) can help treatment planning by optimising stent implantation, which can improve patient outcomes. The aim of this meta-analysis is to compare the efficacy of IVUS and OCT-derived metrics in detecting flow limiting stenoses in non-left main stem lesions. METHODS: A systematic review of PubMed, Medline, and Cochrane databases was performed and identified studies examining the diagnostic accuracy of IVUS and OCT in detecting significant stenoses when compared to FFR. RESULTS: A total of 33 (7537 lesions) studies (24 IVUS, 7 OCT and 2 IVUS & OCT studies) were included in the meta-analysis. Pooled analysis showed that IVUS- and OCT-derived minimum lumen area (MLA) had a similar sensitivity in predicting haemodynamically significant lesions (IVUS-MLA: 0.747 vs OCT-MLA 0.732, p = 0.519). However, OCT-MLA had a higher specificity (0.763 vs 0.665, p < 0.001) and diagnostic accuracy in detecting flow-limiting stenoses than IVUS-MLA (AUC 0.810 vs 0.754, p = 0.045). Sub-analysis of the studies with the clinically significant FFR cut-off value of 0.80 yielded similar results demonstrating that OCT-MLA has a better accuracy than IVUS-MLA in detecting haemodynamically significant stenoses (AUC 0.809 vs 0.750, p = 0.034). CONCLUSIONS: OCT with its superior image resolution appears to be the preferable intravascular imaging modality for the detection of haemodynamically significant stenoses in non-left main stem lesions.

Identifying Cardiac Amyloid in Aortic Stenosis: ECV Quantification by CT in TAVR Patients.

OBJECTIVES: The purpose of this study was to validate computed tomography measured ECV (ECVCT) as part of routine evaluation for the detection of cardiac amyloid in patients with aortic stenosis (AS)-amyloid. BACKGROUND: AS-amyloid affects 1 in 7 elderly patients referred for transcatheter aortic valve replacement (TAVR). Bone scintigraphy with exclusion of a plasma cell dyscrasia can diagnose transthyretin-related cardiac amyloid noninvasively, for which novel treatments are emerging. Amyloid interstitial expansion increases the myocardial extracellular volume (ECV). METHODS: Patients with severe AS underwent bone scintigraphy (Perugini grade 0, negative; Perugini grades 1 to 3, increasingly positive) and routine TAVR evaluation CT imaging with ECVCT using 3- and 5-min post-contrast acquisitions. Twenty non-AS control patients also had ECVCT performed using the 5-min post-contrast acquisition. RESULTS: A total of 109 patients (43% male; mean age 86 ± 5 years) with severe AS and 20 control subjects were recruited. Sixteen (15%) had AS-amyloid on bone scintigraphy (grade 1, n = 5; grade 2, n = 11). ECVCT was 32 ± 3%, 34 ± 4%, and 43 ± 6% in Perugini grades 0, 1, and 2, respectively (p < 0.001 for trend) with control subjects lower than lone AS (28 ± 2%; p < 0.001). ECVCT accuracy for AS-amyloid detection versus lone AS was 0.87 (0.95 for 99mTc-3,3-diphosphono-1,2-propanodicarboxylic acid Perugini grade 2 only), outperforming conventional electrocardiogram and echocardiography parameters. One composite parameter, the voltage/mass ratio, had utility (similar AUC of 0.87 for any cardiac amyloid detection), although in one-third of patients, this could not be calculated due to bundle branch block or ventricular paced rhythm. CONCLUSIONS: ECVCT during routine CT TAVR evaluation can reliably detect AS-amyloid, and the measured ECVCT tracks the degree of infiltration. Another measure of interstitial expansion, the voltage/mass ratio, also performed well.

DPD Quantification in Cardiac Amyloidosis: A Novel Imaging Biomarker.

OBJECTIVES: To assess whether single-photon emission computed tomography (SPECT/CT) quantification of bone scintigraphy would improve diagnostic accuracy and offer a means of quantifying amyloid burden. BACKGROUND: Transthyretin-related cardiac amyloidosis is common and can be diagnosed noninvasively using bone scintigraphy; interpretation, however, relies on planar images. SPECT/CT imaging offers 3-dimensional visualization. METHODS: This was a single-center, retrospective analysis of 99mTc-3,3-diphosphono-1,2-propanodicarboxylic acid (DPD) scans reported using the Perugini grading system (0 = negative; 1 to 3 = increasingly positive). Conventional planar quantification techniques (heart/contralateral lung, and heart/whole-body retention ratios) were performed. Heart, adjacent vertebra, paraspinal muscle and liver peak standardized uptake values (SUVpeak) were recorded from SPECT/CT acquisitions. An SUV retention index was also calculated: (cardiac SUVpeak/vertebral SUVpeak) × paraspinal muscle SUVpeak. In a subgroup of patients, SPECT/CT quantification was compared with myocardial extracellular volume quantification by CT imaging (ECVCT). RESULTS: A total of 100 DPD scans were analyzed (patient age 84 ± 9 years; 52% male): 40 were Perugini grade 0, 12 were grade 1, 41 were grade 2, and 7 were grade 3. Cardiac SUVpeak increased from grade 0 to grade 2; however, it plateaued between grades 2 and 3 (p < 0.001). Paraspinal muscle SUVpeak increased with grade (p < 0.001), whereas vertebral SUVpeak decreased (p < 0.001). The composite parameter of SUV retention index overcame the plateauing of the cardiac SUVpeak and increased across all grades (p < 0.001). Cardiac SUVpeak correlated well (r2 = 0.73; p < 0.001) with ECVCT. Both the cardiac SUVpeak and SUV retention index had excellent diagnostic accuracy (area under the curve [AUC]: 0.999). The heart to contralateral lung ratio performed the best of the planar quantification techniques (AUC: 0.987). CONCLUSIONS: SPECT/CT quantification in DPD scintigraphy is possible and outperforms planar quantification techniques. Differentiation of Perugini grade 2 or 3 is confounded by soft tissue uptake, which can be overcome by a composite SUV retention index. This index can help in the diagnosis of cardiac amyloidosis and may offer a means of monitoring response to therapy.

Effect of evidence-based therapy for secondary prevention of cardiovascular disease: Systematic review and meta-analysis.

BACKGROUND: The combination pharmacotherapy of antiplatelet agents, lipid-modifiers, ACE inhibitors/ARBs and beta-blockers are recommended by international guidelines. However, data on effectiveness of the evidence-based combination pharmacotherapy (EBCP) is limited. OBJECTIVES: To determine the effect of EBCP on mortality and Cardiovascular events in patients with Coronary Heart Disease (CHD) or cerebrovascular disease. METHODS: Publications in EMBASE and Medline up to October 2018 were searched for cohort and case-control studies on EBCP for the secondary prevention of cardiovascular disease. The main outcomes were all-cause mortality and major cardiovascular events. Meta-analyses were performed based on random effects models. RESULTS: 21 studies were included. Comparing EBCP to either monotherapy or no therapy, the pooled risk ratios were 0.60 (95% confidence interval 0.55 to 0.66) for all-cause mortality, 0.70 (0.62 to 0.79) for vascular mortality, 0.73 (0.64 to 0.83) for myocardial infarction and 0.79 (0.68 to 0.91) for cerebrovascular events. Optimal EBCP (all 4 classes of drug prescribed) had a risk ratio for all-cause mortality of 0.50 (0.40 to 0.64). This benefit became more dilute as the number of different classes of drug comprising EBCP was decreased-for 3 classes of drug prescribed the risk ratio was 0.58 (0.49 to 0.69) and for 2 classes, the risk ratio was 0.67 (0.60 to 0.76). CONCLUSIONS: EBCP reduces the risk of all-cause mortality and cardiovascular events in patients with CHD or cerebrovascular disease. The different classes of drugs comprising EBCP work in an additive manner, with optimal EBCP conferring the greatest benefit.

Tetrahydrobiopterin.

The endothelium plays a pivotal role in vascular physiology through a variety of factors, foremost of which is nitric oxide (NO). However, the biochemical mechanisms leading to reduced NO availability and subsequent endothelial dysfunction are not clearly understood. Tetrahydrobiopterin (BH(4)) is an essential cofactor for endothelial NO synthase. Recent preclinical and clinical studies in patients with cardiovascular risk and disease support the central role of reduced BH(4) availability in decreased NO production. This has led to BH(4) supplementation emerging as a possible therapy for conditions characterized by endothelial dysfunction (eg, hypertension, hypercholesterolemia, diabetes, and vascular disease states), and those caused by smoking and aging. Recent advances in drug formulation of BH(4) now offer the potential for better clinical understanding of endothelial function in human health and disease.

Neointima and neoatherosclerotic characteristics in bare metal and first- and second-generation drug-eluting stents in patients admitted with cardiovascular events attributed to stent failure: an optical coherence tomography study.

AIMS: The aim of this study was to assess neoatherosclerotic plaque morphology in bare metal (BMS) and first- and second-generation drug-eluting stents (DES) in patients presenting with an event attributed to stent failure. METHODS AND RESULTS: Thirty-five patients (11 implanted with BMS, 13 with a first-generation and 11 with a second-generation DES) admitted with an event due to stent failure who had neoatherosclerotic lesions on optical coherence tomography were included in the analysis. The lumen and stent borders were detected and the lipid and calcific tissue were identified in the neointima and their burden was estimated. The neointima attenuation and backscatter indices were computed and compared between the different stent types. Although there were no differences in the neointima burden, the BMS group exhibited thinner fibrous caps (p<0.001), and a numerically increased incidence of lipid-rich plaques (p=0.052) and macrophage accumulation (p=0.012). Neointima discontinuities (p=0.009) and thrombus (p=0.032) were seen more often in first-generation DES. In all stent types, neoatherosclerosis had focal manifestations. In neoatherosclerotic lesions the attenuation and backscatter indices were increased in BMS (p=0.031 and p=0.018, respectively) compared to DES; however, there were no differences between stents in the attenuation indices in subsegments located distally to neoatherosclerotic lesions which had low values in all stent types. CONCLUSIONS: Although there are differences in lipid burden and neointima characteristics in different stent types, in all stents neoatherosclerosis has focal manifestations indicating that, irrespective of the stent type, focal triggers are involved in the generation of vulnerable neolesions.