Incidence of left ventricular thrombus following STEMI in the modern era via multimodality imaging: A systematic review and meta-analysis.

Background: Left ventricular thrombus (LVT) is a significant complication in STEMI. Previous studies were conducted prior to modern timely percutaneous reperfusion networks. Current expert opinion suggests incidence in the current era has decreased. We conducted a systematic review and meta-analysis to better understand the incidence and diagnosis of LVT in patients with STEMI treated with timely percutaneous techniques as assessed by multimodality imaging. Methods: Cochrane, EMBASE, LILACS, and MEDLINE were searched over the last 10 years only including studies using contemporary techniques. The primary outcome was detection of LVT in patients via echocardiogram with or without contrast or Cardiac MRI (cMRI) following STEMI (both anterior and any territory) treated with PCI. Data was pooled across studies and statistical analysis was conducted via random effects model. Results: 31 studies were included. 18 studies included data on any territory STEMI, totaling 14,172 patients, and an incidence of 5.6% [95% CI 4.3-7.0]. 18 studies were included in analysis for anterior STEMI, totaling 7382 patients and incidence of 12.7% [95% CI 9.8-15.6]. Relative to cMRI as a gold standard, the sensitivity of non-contrast echocardiography to detect LVT was 58.2% [95% CI 46.6-69.2] with a specificity of 97.8% [95% CI 96.3-98.8]. Conclusions: Incidence of LVT in STEMI patients treated with contemporary timely percutaneous revascularization is in keeping with historical data and remains significant, suggesting this remains an ongoing issue for further investigation. Numerically, both cMRI and contrast echo detected more LVT compared to non-contrast echo in any-territory STEMI patients.

Rationale and Design of the Rivaroxaban Post-Transradial Access for the Prevention of Radial Artery Occlusion Trial (CAPITAL-RAPTOR).

INTRODUCTION: Transradial access (TRA) has rapidly emerged as the preferred vascular access site for coronary angiography and percutaneous coronary intervention. Radial artery occlusion (RAO) remains as an important complication of TRA as it precludes future ipsilateral transradial procedures. While intraprocedural anticoagulation has been studied extensively, the definitive role of postprocedural anticoagulation has not yet been established. METHODS AND ANALYSIS: The Rivaroxaban Post-Transradial Access for the Prevention of Radial Artery Occlusion trial is a multicentre, prospective, randomised, open-label, blinded-endpoint design study investigating the efficacy and safety of rivaroxaban to reduce the incidence of RAO. Eligible patients will undergo randomisation to receive either rivaroxaban 15 mg once daily for 7 days or to no additional postprocedural anticoagulation. Doppler ultrasound to assess radial artery patency will be performed at 30 days. ETHICS AND DISSEMINATION: The study protocol has been approved by the Ottawa Health Science Network Research Ethics Board (approval number 20180319-01H). The study results will be disseminated via conference presentations and peer-reviewed publications. TRIAL REGISTRATION NUMBER: NCT03630055.

The Effect of Sex on Door-to-Balloon Time in Patients Presenting With ST-Elevation Myocardial Infarction and Referred for Primary Percutaneous Coronary Intervention: A Systematic Review.

Timely reperfusion using primary percutaneous coronary intervention (pPCI) is the cornerstone of acute ST-elevation myocardial infarction (STEMI) management. We conducted a systematic review to examine the effect of sex on door-to-balloon (D2B) time and symptom-to-balloon (S2B) time. We observed longer D2B times and S2B times in female patients presenting with STEMI and referred for pPCI when compared to male patients. Future work is required to try and elucidate and mitigate sex-based front-line treatment delays for female STEMI patients.

Femoral plaque burden by ultrasound is a better indicator of significant coronary artery disease over ankle brachial index.

The ankle-brachial index is a commonly used tool for identifying peripheral artery disease for cardiovascular risk stratification. An abnormal ankle-brachial index occurs only following extensive peripheral atherosclerosis occlusion, and thus has poor sensitivity for coronary atherosclerosis. There is a critical need for the development of tools that can detect risk prior to advanced stages of atherosclerosis. We sought to determine the sensitivity of femoral ultrasound for coronary artery disease. In this prospective, cross-sectional study, participants (n = 124) underwent ankle-brachial index measurement and femoral ultrasound for assessment of intima-media thickness, maximal plaque height, and total plaque area following coronary angiography. Receiver operating characteristic areas under the curve were plotted for identifying significant coronary artery disease (≥ 50% stenosis). Logistic regression was utilized to evaluate associations. 64% of participants had significant, angiography-confirmed coronary artery disease. Femoral ultrasound plaque area yielded the highest area under the curve for detecting significant coronary disease (area under the curve = 0.731). In contrast, an abnormal ankle-brachial index (≤ 0.90) produced an area under the curve of 0.568. Femoral ultrasound had a higher sensitivity (85%) than the ankle-brachial index (25%) for ruling out significant coronary artery disease. Both ankle-brachial index and femoral ultrasound have similar capacity to detect peripheral artery disease. Femoral ultrasound has a significantly greater discriminatory power than ankle-brachial index to detect clinically significant coronary artery disease. Ultrasound-captured femoral plaque burden directly delineates the extent of peripheral arterial disease and is better at ruling out significant coronary atherosclerosis than the ankle-brachial index.

Antithrombotic Therapy After Percutaneous Coronary Intervention in Patients With Atrial Fibrillation: Findings From the CONNECT AF+PCI Study.

BACKGROUND: In patients with atrial fibrillation (AF) undergoing percutaneous coronary intervention (PCI), selecting an antithrombotic regimen requires balancing risks of ischemic cardiac events, stroke, and bleeding. METHODS: We studied 467 patients with AF undergoing PCI in the time period from December 2015 to July 2018 identified via a chart audit by 47 Canadian cardiologists in the CONNECT AF+PCI (the Coordinated National Network to Engage Interventional Cardiologists in the Antithrombotic Treatment of Patients With Atrial Fibrillation Undergoing Percutaneous Coronary Intervention) study, to determine patterns of initial antithrombotic therapy selection. RESULTS: The median (25th, 75th percentile) CHADS2 score was 2 (1, 3), and PCI was performed in the setting of acute coronary syndrome in 62.1%. Triple antithrombotic therapy (TAT) was the initial treatment in 62.7%, dual-pathway therapy in 25.7%, and dual antiplatelet therapy in 11.6%, with a temporal increase in use of dual-pathway therapy during the course of the study; median intended TAT duration was 1 (1, 3) month. Compared with patients selected for TAT, patients selected for dual-pathway therapy were less likely to have prior myocardial infarction (35.8% vs 25.8%, P = 0.045) and prior PCI (33.8% vs 23.3%, P = 0.03), and they received shorter total length of stents (38 [23, 56] vs 30 [20, 46] mm, P = 0.03). Patients selected for dual-pathway therapy had a higher prevalence of prior stroke/transient ischemic attack (13.0% vs 23.3%, P = 0.01). There was no difference in prevalence of anemia (21.5% vs 25.8%, P = 0.30). Use of dual-pathway therapy was similar among patients with acute coronary syndrome and those with stable disease (24.1% vs 28.2%, P = 0.32). CONCLUSIONS: Approximately one-quarter of AF patients undergoing PCI are treated with dual-pathway therapy in Canadian practice, with its use increasing during the studied period. Patients selected for dual-pathway therapy have less-complex coronary disease history and intervention.

INTRODUCTION: Les patients atteints de fibrillation auriculaire (FA) qui subissent une intervention coronarienne percutanée (ICP) et choisissent un schéma posologique antithrombotique ont besoin de peser les risques d'événements cardiaques d'origine ischémique, d'accidents vasculaires cérébraux et d'hémorragies. MÉTHODES: Les 467 patients atteints de FA ayant subi une ICP de décembre 2015 à juillet 2018 qui ont fait l'objet de notre étude ont été trouvés lors de la vérification des dossiers par 47 cardiologues canadiens de l'étude CONNECT AF+PCI ( Co ordinated N ational N etwork to E ngage Interventional C ardiologists in the Antithrombotic T reatment of Patients With A trial F ibrillation Undergoing P ercutaneous C oronary I ntervention) pour déterminer les schémas de sélection du traitement antithrombotique initial. RÉSULTATS: Le score CHADS2 médian (25e, 75e percentile) était de 2 (1, 3), et l'ICP avait été réalisée dans le cadre du syndrome coronarien aigu chez 62,1 % des patients. La trithérapie antithrombotique (TTA) était le traitement initial chez 62,7 % des patients, la bithérapie, chez 25,7 % des patients, et la bithérapie antiplaquettaire, chez 11,6 % des patients, mais il y avait une augmentation temporelle dans l'utilisation de la bithérapie durant l'étude; la durée médiane prévue de la TTA était de 1 (1, 3) mois. Comparativement aux patients sélectionnés pour la TTA, les patients sélectionnés pour la bithérapie étaient moins susceptibles d'avoir eu un infarctus du myocarde précédent (35,8 % vs 25,8 %, P = 0,045) et une ICP précédente (33,8 % vs 23,3 %, P = 0,03), et recevaient des endoprothèses de longueur totale plus courte (38 [23, 56] vs 30 [20, 46] mm, P = 0,03). Les patients sélectionnés pour la bithérapie montraient une prévalence plus élevée d'accidents vasculaires cérébraux/accidents ischémiques transitoires (13,0 % vs 23,3 %, P = 0,01). Il n'existait aucune différence dans la prévalence de l'anémie (21,5 % vs 25,8 %, P = 0,30). L'utilisation de la bithérapie était similaire chez les patients atteints d'un syndrome coronarien aigu et chez les patients dont la maladie était stable (24,1 % vs 28,2 %, P = 0,32). CONCLUSIONS: Dans la pratique canadienne, environ le quart des patients atteints de FA qui subissent une ICP sont traités par bithérapie, mais durant la période étudiée, son utilisation avait augmenté. Les patients sélectionnés pour la bithérapie ont des antécédents et des interventions liées aux maladies coronariennes moins complexes.

Preprocedural computed tomography angiography in differentiating chronic total from subtotal coronary occlusions.

INTRODUCTION: Differentiation of chronic total occlusion (CTO) from subtotal coronary occlusions (STOs) is often difficult to make from coronary angiography. These differences are very important, as the technical expertise and tools required are significantly different for revascularization of these lesions. We sought to determine if preprocedural computed tomography angiography (CTA) can help better diagnose and differentiate CTO from STO. METHODS: We searched three databases (Ovid MEDLINE, EMBASE, EBM reviews) from 1 January 1946 to 1 March 2019. Studies reporting on the use of computed tomography (CT) to aid in CTO revascularization were included. Case reports and case series were excluded. RESULTS: We identified 577 articles, and using the Preferred Reporting Items for Systematic Reviews and Meta-analyses method, 4 articles met prespecified inclusion criteria. A total of 669 patients were included. The statistically significant CT-derived parameters determined to help differentiate CTO from STO were found to include longer lesion length (four out of four studies), larger contrast density difference (one out of four studies), presence of collaterals (two out of four studies) and the presence of the reverse attenuation gradient sign (two out of four studies). CONCLUSION: This systematic review shows the utility of preprocedural CTA to help differentiate CTO from STO using a number of CT-derived parameters as above. Further, this study highlights the need for further research to develop specific validated parameters for differentiation of CTO and STO.

The Effect of Transcatheter Mitral Valve Repair on Short-Term Mortality in Patients With Chronic Kidney Disease - A Systematic Review and Meta-Analysis.

Transcatheter Mitral Valve Repair (TMVr) offers clinically significant benefit to select symptomatic patients with severe mitral regurgitation (MR). We conducted a systematic review and meta-analysis of clinical trials and observational studies to identify the effect of pre-procedural Chronic Kidney disease (CKD) on short-term mortality in TMVr. We found CKD is a predictor of 30-day mortality in patients undergoing TMVr. Specifically, a GFR < 30 mL/min conveys a significant increase in 30-day mortality. This is significant for patient selection, prognostication, as well as identifies an area of need for further research. SUMMARY FOR ANNOTATED TABLE OF CONTENTS: A systematic review and meta-analysis looking at short-term mortality in patients undergoing Transcatheter Mitral Valve Repair with chronic kidney disease. Findings show severe renal disease is associated with increased 30-day mortality.

Combined Femoral and Carotid Plaque Burden Identifies Obstructive Coronary Artery Disease in Women.

BACKGROUND: It remains difficult to assess cardiovascular risk in symptomatic women. The development of femoral plaque precedes adverse cardiovascular events. However, associations of femoral plaque burden with coronary artery disease (CAD) severity and extent are unknown. The aim of this study was to determine sex-specific plaque quantification markers by vascular ultrasound for identifying significant, obstructive CAD. METHODS: In this cross-sectional study, 500 participants (34% women) underwent carotid and femoral ultrasound following coronary angiography. Maximal plaque height and total plaque area were quantified. Logistic regression was used to determine associations of plaque burden with significant, obstructive CAD (≥50% stenosis), when adjusted for age and cardiac risk factors. CAD prediction was evaluated using receiver operating characteristic areas under the curve (AUCs). RESULTS: Two hundred thirty-one men (70%) and 78 women (46%) had significant CAD. A combined assessment of femoral bifurcation and carotid maximal plaque height was the most accurate identifier of CAD in men (AUC = 0.773, cutoff ≥ 2.7 mm, 87% sensitivity, 53% specificity) but a poorer indicator of CAD in women (AUC = 0.659, P < .01). In contrast, the strongest identification of CAD in women was achieved by a combined analysis of common femoral and carotid total plaque area (AUC = 0.764, cutoff ≥ 42.0 mm2, 86% sensitivity, 53% specificity). At this value, more than half of women with false-positive stress test results were correctly identified as having no significant CAD. CONCLUSION: Combined femoral and carotid plaque burden assessments effectively ruled out significant disease in both sexes. Vascular ultrasound may have particular value for cardiovascular risk stratification in women, in whom traditional screening tools are less effective.

Carotid intraplaque neovascularization predicts coronary artery disease and cardiovascular events.

AIMS: It is thought that the majority of cardiovascular (CV) events are caused by vulnerable plaque. Such lesions are rupture prone, in part due to neovascularization. It is postulated that plaque vulnerability may be a systemic process and that vulnerable lesions may co-exist at multiple sites in the vascular bed. This study sought to examine whether carotid plaque vulnerability, characterized by contrast-enhanced ultrasound (CEUS)-assessed intraplaque neovascularization (IPN), was associated with significant coronary artery disease (CAD) and future CV events. METHODS AND RESULTS: We investigated carotid IPN using carotid CEUS in 459 consecutive stable patients referred for coronary angiography. IPN was graded based on the presence and location of microbubbles within each plaque (0, not visible; 1, peri-adventitial; and 2, plaque core). The grades of each plaque were averaged to obtain an overall score per patient. Coronary plaque severity and complexity was also determined angiographically. Patients were followed for 30 days following their angiogram. This study found that a higher CEUS-assessed carotid IPN score was associated with significant CAD (≥50% stenosis) (1.8 ± 0.4 vs. 0.5 ± 0.6, P < 0.0001) and greater complexity of coronary lesions (1.7 ± 0.5 vs. 1.3 ± 0.8, P < 0.0001). Furthermore, an IPN score ≥1.25 could predict significant CAD with a high sensitivity (92%) and specificity (89%). The Kaplan-Meier analysis demonstrated a significantly higher proportion of participants having CV events with an IPN score ≥1.25 (P = 0.004). CONCLUSION: Carotid plaque neovascularization was found to be predictive of significant and complex CAD and future CV events. CEUS-assessed carotid IPN is a clinically useful tool for CV risk stratification in high-risk cardiac patients.

2018 Canadian Cardiovascular Society/Canadian Association of Interventional Cardiology Focused Update of the Guidelines for the Use of Antiplatelet Therapy.

Antiplatelet therapy (APT) has become an important tool in the treatment and prevention of atherosclerotic events, particularly those associated with coronary artery disease. A large evidence base has evolved regarding the relationship between APT prescription in various clinical contexts and risk/benefit relationships. The Guidelines Committee of the Canadian Cardiovascular Society and Canadian Association of Interventional Cardiology publishes regular updates of its recommendations, taking into consideration the most recent clinical evidence. The present update to the 2011 and 2013 Canadian Cardiovascular Society APT guidelines incorporates new evidence on how to optimize APT use, particularly in situations in which few to no data were previously available. The recommendations update focuses on the following primary topics: (1) the duration of dual APT (DAPT) in patients who undergo percutaneous coronary intervention (PCI) for acute coronary syndrome and non-acute coronary syndrome indications; (2) management of DAPT in patients who undergo noncardiac surgery; (3) management of DAPT in patients who undergo elective and semiurgent coronary artery bypass graft surgery; (4) when and how to switch between different oral antiplatelet therapies; and (5) management of antiplatelet and anticoagulant therapy in patients who undergo PCI. For PCI patients, we specifically analyze the particular considerations in patients with atrial fibrillation, mechanical or bioprosthetic valves (including transcatheter aortic valve replacement), venous thromboembolic disease, and established left ventricular thrombus or possible left ventricular thrombus with reduced ejection fraction after ST-segment elevation myocardial infarction. In addition to specific recommendations, we provide values and preferences and practical tips to aid the practicing clinician in the day to day use of these important agents.

Radiation safety in the cardiac catheterization lab: A time series quality improvement initiative.

BACKGROUND: Interventional cardiologists have one of the highest annual radiation exposures yet systems of care that promote radiation safety in cardiac catheterization labs are lacking. This study sought to reduce the frequency of radiation exposure, for PCI procedures, above 1.5Gy in labs utilizing a Phillips system at our local institution by 40%, over a 12-month period. METHODS: We performed a time series study to assess the impact of different interventions on the frequency of radiation exposure above 1.5Gy. Process measures were percent of procedures where collimation and magnification were used and percent of completion of online educational modules. Balancing measures were the mean number of cases performed and mean fluoroscopy time. INTERVENTIONS: Information sessions, online modules, policies and posters were implemented followed by the introduction of a new lab with a novel software (AlluraClarity©) to reduce radiation dose. RESULTS: There was a significant reduction (91%, p<0.05) in the frequency of radiation exposure above 1.5Gy after utilizing a novel software (AlluraClarity©) in a new Phillips lab. Process measures of use of collimation (95.0% to 98.0%), use of magnification (20.0% to 14.0%) and completion of online modules (62%) helped track implementation. The mean number of cases performed and mean fluoroscopy time did not change significantly. CONCLUSION: While educational strategies had limited impact on reducing radiation exposure, implementing a novel software system provided the most effective means of reducing radiation exposure.

Impact of a structured referral algorithm on the ability to monitor adherence to appropriate use criteria for transthoracic echocardiography.

BACKGROUND: Many free-form-text referral requisitions for transthoracic echocardiography (TTE) provide insufficient information to adequately evaluate their adherence to Appropriate Use Criteria (AUC). We developed a structured referral requisition algorithm based on requisition deficiencies identified retrospectively in a derivation cohort of 1303 TTE referrals and evaluated the performance of the algorithm in a consecutive series of cardiology outpatient referrals. METHODS: The validation cohort comprised 286 consecutive TTE outpatient cardiology referrals over a 2-week period. The relevant AUC indication was identified from information extracted from the free-form-text requisition. The structured referral algorithm was applied prospectively to the same cohort using information from the free-form-text requisition, electronic medical record and ordering clinicians. Referrals were classified as appropriate, uncertain, non-adherent (inappropriate) or unclassifiable based on the American College of Cardiology Foundation 2011 AUC. RESULTS: Only 28.7 % of free-form-text requisitions provided adequate information to identify the relevant AUC indication, as compared to 94.4 % of referrals using the structured referral algorithm (p < 0.001). The structured algorithm improved identification in the AUC categories of general evaluation of cardiac structure/function (100 % vs. 43.0 %, p < 0.001); valvular function (100 % vs. 23.0 %, p < 0.001); hypertension, heart failure or cardiomyopathy (100 % vs. 20.3 %, p < 0.001); and adult congenital heart disease (100 % vs. 0 %, p < 0.001). By applying the algorithm, the number of identifiable non-adherent studies increased from 2.6 to 10.4 % (p <0.001). CONCLUSIONS: Use of a structured TTE referral algorithm, as opposed to a free-form-text requisition, allowed the vast majority of referrals to be monitored for AUC adherence and facilitated the identification of potentially inappropriate referrals.

Ticagrelor in Triple Antithrombotic Therapy: Predictors of Ischemic and Bleeding Complications.

BACKGROUND: Patients on dual antiplatelet therapy following percutaneous coronary intervention often have indications for concurrent oral anticoagulation or triple antithrombotic therapy (TT). Although TT may decrease ischemic complications, it may confer increased bleeding risk. HYPOTHESIS: We hypothesize that the use of ticagrelor in TT is associated with higher risk of complications; accordingly, we sought to determine predictors of complications in patients on TT. METHODS: Patients discharged on TT after percutaneous coronary intervention were followed prospectively for 12 months. The primary endpoint was a composite of ischemic (death, myocardial infarction, stroke) and major bleeding complications or net adverse clinical event (NACE). A major secondary endpoint was BARC (Bleeding Academic Research Consortium) types 2, 3, or 5 bleeding. Outcomes were compared between ticagrelor- and clopidogrel-treated patients. Multivariable analyses were performed to elucidate predictors of complications. RESULTS: Twenty-seven of 152 patients discharged on TT were on ticagrelor. NACE occurred in 52% of patients and BARC 2, 3, or 5 bleeding occurred in 18%. There was no difference in the primary or secondary outcome between ticagrelor vs clopidogrel subgroup. On logistic regressions, use of TT in patients with acute coronary syndrome (P = 0.002) and bridging in with ticagrelor (P = 0.02) were associated with increased NACE. Low estimated glomerular filtration rate was an independent predictor of bleeding (P = 0.03). CONCLUSIONS: The risk of bleeding and ischemic complications among patients on TT is similar between those on ticagrelor and clopidogrel. However, caution with use of bridging anticoagulation should be taken when using ticagrelor.

A pharmacodynamic comparison of a personalized strategy for anti-platelet therapy versus ticagrelor in achieving a therapeutic window.

BACKGROUND: A therapeutic window in antiplatelet treatment has been associated with concurrent lowering of bleeding and ischemic risks. Prasugrel and ticagrelor provide potent platelet inhibition, but may increase bleeding. No study has evaluated a personalized therapy with selective use of novel P2Y12 inhibitory agents compared to empiric ticagrelor use. The objective of this study was to compare a personalized anti-platelet therapy strategy to empiric ticagrelor in achieving a therapeutic window. METHODS: Using the CAPITAL registry, we performed a retrospective analysis to evaluate a personalized anti-platelet therapy (PAT) strategy, using a pharmacogenetic approach, and compared it to empiric ticagrelor. In the PAT group, carriers of CYP2C19*2 received prasugrel and non-carriers received clopidogrel. The primary outcome was the proportion of patients within a validated therapeutic window, after a steady state treatment (≥48h) of antiplatelet therapy, as measured by a P2Y12 reaction unit (PRU) >85 and <208. RESULTS: Of 199 patients with platelet function measurements, 150 received PAT, while 49 received ticagrelor. Significantly more patients on PAT achieved the primary outcome (50.0% vs. 4.1%, p<0.0001). This was predominantly driven by an increase in low on-treatment reactivity with ticagrelor (95.9% vs. 37.3%, p<0.0001). Multivariable analysis demonstrated PAT to be the strongest predictor of achieving PRU values within the therapeutic window (odds ratio 20.27; 95% CI: 4.33-94.82, p=0.0001). CONCLUSION: Patients treated with PAT were more likely to achieve a therapeutic window compared to a strategy of ticagrelor. Future prospective evaluation of novel PAT strategies will be required to prove clinical utility.

Usefulness of the Agatston score = 0 to exclude ischemic cardiomyopathy in patients with heart failure.

Quantification of coronary artery calcium has prognostic value and is commonly used in asymptomatic patients. Routine clinical use of coronary artery calcium in other populations remains uncertain. We sought to understand the potential application of the Agatston score in patients with heart failure (HF). For this purpose, 3 populations were identified: (1) patients with an Agatston score equal to 0, (2) patients with high-risk coronary artery disease (CAD) defined as 3-vessel, left main, or 2-vessel disease involving the proximal left anterior descending coronary artery, and (3) patients with HF symptoms and left ventricular (LV) ejection fraction <50%. Excluding patients with HF or LV dysfunction, 738 patients (mean age 52 ± 10 years, 43% men) had an Agatston score equal to 0. Of these, 18 (2%) had obstructive CAD (diameter stenosis ≥50%), 8 (1%) had diameter stenoses ≥70%, and none had high-risk CAD. The 74 patients with high-risk CAD without LV dysfunction had high Agatston scores (mean 895 ± 734, median 716, range 50 to 3,210). In total 153 patients with a history of HF and abnormal ejection fraction were identified. All 13 patients with ischemic cardiomyopathy had Agatston scores >0, whereas 46 of 140 patients (30.1%) with nonischemic causes had an Agatston score equal to 0. An Agatston score equal to 0 identified nonischemic causes with a specificity of 100% (confidence interval 90 to 100) and positive predictive value of 100% (confidence interval 90 to 100). Agatston score equal to 0 had incremental value to pretest probability for CAD. In conclusion, an Agatston score equal to 0 confers a very low likelihood of obstructive CAD, appears to rule out high-risk CAD, and thus may be used to rule out ischemic cardiomyopathy in patients with HF.

Effects of mitral valve surgery on myocardial energetics in patients with severe mitral regurgitation.

BACKGROUND: Hemodynamically significant mitral regurgitation (MR) may alter left ventricular (LV) myocardial energy requirements. The effects of MR and subsequent corrective mitral valve (MV) surgery on myocardial energetics are not well understood. A better understanding of myocardial energetics and the LV responses to changes in preload and afterload may assist with the understanding of mitral regurgitation and its effect on the LV. We sought to determine the effects of MV surgery on forward stroke work, myocardial oxidative metabolism, and myocardial efficiency. METHODS AND RESULTS: Prospectively enrolled patients with chronic, severe, nonischemic mitral regurgitation underwent echocardiography, radionuclide angiography, and C-11 acetate positron emission tomography to measure LV volumes, ejection fraction, and oxidative metabolism before and 1 year after MV surgery. Forward and total stroke work corrected for oxidative metabolism was used to estimate efficiency using the work metabolic index. Fourteen patients (age, 59+/- 8 years) with myxomatous MV were enrolled. One year after MV surgery, there was a reduction in LV end-diastolic and end-systolic volumes (231+/-86 to 131+/-21 mL; P<0.01 and 98+/-53 to 55+/-17 mL; P<0.01). Forward stroke volume increased (58.1+/-15.0 to 75.5+/-23 mL; P<0.01), LV ejection fraction was preserved without a significant change in oxidative metabolism. Forward work metabolic index improved (4.99+/-1.32 x 10(6) to 6.59+/-2.45 x 10(6) mm Hg x mL/m(2); P=0.02). This was not at the expense of total work metabolic index, which was preserved. CONCLUSIONS: MV surgery has a beneficial effect on forward stroke volume and forward work metabolic index without adverse effects on oxidative metabolism or total work metabolic index.