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Background: There are discrepancies in the quantitative echocardiographic criteria for the right ventricle (RV) between the revised task force criteria (TFC) for Arrhythmogenic Right Ventricular Cardiomyopathy/Dysplasia (ARVC/D) and the guidelines for RV assessment endorsed by American Society of Echocardiography (ASE). Importantly, these criteria do not take into account potential adaptation of the RV to exercise. The goal of this study was to compare the revised TFC quantitative echocardiographic parameters in patients with ARVC/D, athletes and matched controls., Methods: Echocardiographic parameters of the RV were retrospectively collected in patients who fulfilled the TFC for ARVC/D, an age- matched, sex-matched, and body surface area-matched control population, and athletes (defined as individuals who exercised for more than 7 hours per week). Patients with structural heart disease were excluded in the control and athlete groups., Results: Twenty patients with ARVC/D, 11 athletes and 20 matched controls were included. There was no significant difference between ARVC/D patients and athletes with the exception of the parasternal long axis right ventricular outflow tract diameter. All parameters were significantly different between ARVC/D patients and the control group. Furthermore, when subjects were categorized into meeting 1 major revised TFC/abnormal ASE criteria or not, only ASE criteria were able to differentiate ARVC/D from control population. Both were unable to differentiate ARVC/D from athletes., Conclusions: Right ventricle quantitative echocardiographic criteria in the revised TFC are not specific for ARVC/D. Care should be taken in applying these criteria in athletes., (© 2019 Wiley Periodicals, Inc.)

Clinical management of patients with only moderate aortic stenosis (AS) but symptoms of heart failure with a reduced left ventricular ejection fraction (HFrEF) is challenging. Current guidelines recommend clinical surveillance with multimodality imaging; aortic valve replacement (AVR) is deferred until the stenosis becomes severe. Given the known benefits of afterload reduction in management of patients with HFrEF, it has been hypothesized that AVR may be beneficial in patients with only moderate AS who present with HFrEF. In this article, we first review the current approach for management of patients with moderate AS and HFrEF based on close clinical and imaging surveillance with AVR delayed until AS is severe. We then discuss the case for transcatheter AVR (TAVR) earlier in the disease course, when AS is moderate, based on stress echocardiographic data. We conclude with a detailed summary of the TAVR UNLOAD (Transcatheter Aortic Valve Replacement to UNload the Left Ventricle in Patients With ADvanced Heart Failure) trial, in which patients with moderate AS and HFrEF are randomized to guideline-directed heart failure therapy alone versus guideline-directed heart failure therapy plus TAVR., (Copyright © 2019 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Objective: Transcatheter aortic valve replacement (TAVR) reduces left ventricular (LV) afterload and improves prognosis in aortic stenosis (AS) patients. However, LV afterload consists of both valvular and arterial loads, and the benefits of TAVR may be attenuated if the arterial load dominates. We proposed a new hemodynamic index, the Relative Valve Load (RVL), a ratio of mean gradient (MG) and valvuloarterial impedance (Zva), to describe the relative contribution of the valvular load to the global LV load, and examined whether RVL predicted patient outcome following TAVR., Methods: A total of 258 patients with symptomatic severe AS (indexed aortic valve area (AVA)<0.6cm2/m2, AR≤2+) underwent successful TAVR at the University of Ottawa Heart Institute and had clinical follow-up to 1-year post-TAVR. Pre-TAVR MG, AVA, percent stroke work loss (%SWL), Zva and RVL were measured by echocardiography. The primary endpoint was all cause mortality at 1-year post TAVR., Results: There were 53 deaths (20.5%) at 1-year. RVL≤7.95ml/m2 had a sensitivity of 60.4% and specificity of 75.1% for identifying all cause mortality at 1-year post-TAVR and provided better specificity than MG<40 mmHg, AVA>0.75cm2, %SWL≤25% and Zva>5mmHg/ml/m2 despite equivalent or better sensitivity. In multivariable Cox analysis, RVL≤7.95ml/m2 was an independent predictor of all cause mortality (HR 3.2, CI 1.8-5.9; p<0.0001). RVL≤7.95ml/m2 was predictive of all cause mortality in both low flow and normal flow severe AS., Conclusions: RVL is a strong predictor of all-cause mortality in severe AS patients undergoing TAVR. A pre-procedural RVL≤7.95ml/m2 identifies AS patients at increased risk of death despite TAVR and may assist with decision making on the benefits of TAVR.

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.

Background: Monitoring the adherence to Appropriateness Use Criteria (AUC) has been identified as an important component for the accreditation of echocardiography laboratories. Referral requisitions are a logical tool to rapidly determine the appropriateness of transthoracic echocardiography (TTE) referrals, however data is lacking. We investigated whether standard free-form-text TTE referral requisitions can be used to evaluate AUC adherence., Methods: Consecutive TTE referral requisitions to the University of Ottawa Heart Institute echocardiography laboratory were reviewed over a four-week period. Indication on the requisition was matched with the relevant indication on the 2011 American College of Cardiology Foundation (ACCF) AUC. Requisitions that did not provide sufficient information to identify the relevant AUC indication were identified as inadequate. For inadequate requisitions, reason for the referral was clarified through medical records and referring physicians., Results: Of the 1303 requisitions, 26.2% did not provide adequate information to determine adherence to AUC, despite a non-adherence (inappropriate) rate of only 6.1% in the referral population. Indication for referral, physician specialty, outpatient status, and prior echocardiogram were independent predictors of inadequate requisitions (p < 0.001, respectively). The most common reasons for inadequate requisitions were a failure to report: 1) change in clinical status, 2) date of a prior echocardiogram, and 3) type and/or severity of a valve lesion. Inclusion of this information would have decreased the inadequacy rate by 56%., Conclusion: In a large, academic echocardiography laboratory, over one quarter of free-form-text TTE requisitions are inadequate to evaluate AUC adherence. Structured requisition formats requiring AUC-relevant information are needed to facilitate the practical application of AUC in the echocardiography laboratory.

Takotsubo cardiomyopathy has become a well recognized mimicker of acute coronary syndrome. Patients generally do well, although a minority can develop life-threatening complications. We present a case of 1 such patient in a branched self-assessment format designed to challenge the reader's clinical management skills., (Copyright © 2015 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.)

Purpose of Review: Nearly half of patients presenting with heart failure have a preserved left ventricular ejection fraction (LVEF), previously known as diastolic heart failure. The diagnosis requires fulfillment of three criteria: signs or symptoms of heart failure, presence of a normal LVEF, and evidence of diastolic dysfunction. Two of the criteria can be evaluated by echocardiography. This article reviews the echocardiographic approach to the patient with suspected heart failure with a normal left ventricular ejection fraction (HFNEF)., Recent Findings: Echocardiography is the primary modality for evaluating left ventricular (LV) systolic and diastolic function in heart failure patients. Measurements of LVEF from two-dimensional echocardiography can have significant variability despite the use of quantitative methods. The use of contrast agents and three-dimensional echocardiography can improve the accuracy. Newer modalities of tissue Doppler imaging and deformation imaging are challenging the concept that systolic function is preserved in HFNEF. Evaluation of diastolic function with echocardiography requires a comprehensive approach using multiple modalities to quantitate transmitral flow, pulmonary venous flow, mitral annular motion, myocardial deformation, and cardiac structure. The clinical applicability of parameters used for evaluating diastolic function and filling pressures is dependent on the LVEF, necessitating a unique approach in patients with suspected HFNEF., Summary: A comprehensive examination with knowledge of the potential limitations of echocardiography is required to accurately interpret LV systolic and diastolic function in patients with suspected HFNEF.

Guidelines for the provision of echocardiography in Canada were jointly developed and published by the Canadian Cardiovascular Society and the Canadian Society of Echocardiography in 2005. Since their publication, recognition of the importance of echocardiography to patient care has increased, along with the use of focused, point-of-care echocardiography by physicians of diverse clinical backgrounds and variable training. New guidelines for physician training and maintenance of competence in adult echocardiography were required to ensure that physicians providing either focused, point-of-care echocardiography or comprehensive echocardiography are appropriately trained and proficient in their use of echocardiography. In addition, revision of the guidelines was required to address technological advances and the desire to standardize echocardiography training across the country to facilitate the national recognition of a physician's expertise in echocardiography. This paper summarizes the new Guidelines for Physician Training and Maintenance of Competency in Adult Echocardiography, which are considerably more comprehensive than earlier guidelines and address many important issues not previously covered. These guidelines provide a blueprint for physician training despite different clinical backgrounds and help standardize physician training and training programs across the country. Adherence to the guidelines will ensure that physicians providing echocardiography have acquired sufficient expertise required for their specific practice. The document will also provide a framework for other national societies to standardize their training programs in echocardiography and will provide a benchmark by which competency in adult echocardiography may be measured., (Copyright © 2011 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.)

Recognizing the central role of echocardiographic examinations in the assessment of most cardiac disorders and the need to ensure the provision of these services in a highly reliable, timely, economical and safe manner, the Canadian Cardiovascular Society and Canadian Society of Echocardiography undertook a comprehensive review of all aspects influencing the provision of echocardiographic services in Canada. Five regional panels were established to develop preliminary recommendations in the five component areas, which included the echocardiographic examination, the echocardiographic laboratory and report, the physician, the sonographer and indications for examinations. Membership in the panels was structured to recognize the regional professional diversity of individuals involved in the provision of echocardiography. In addition, a focus group of cardiac sonograhers was recruited to review aspects of the document impacting on sonographer responsibilities and qualification. The document is intended to be used as a comprehensive and practical reference for all of those involved in the provision of echocardiography in Canada.

Aims Severe aortic valve stenosis (AS) is defined by an aortic valve area (AVA) <1 cm2 or an AVA indexed to body surface area (BSA) <0.6 cm/m2, despite little evidence supporting the latter approach and important intrinsic limitations of BSA indexation. We hypothesized that AVA indexed to height (H) might be more applicable to a wide range of populations and body morphologies and might provide a better predictive accuracy. Methods and results In 1298 patients with degenerative AS and preserved ejection fraction from three different countries and continents (derivation cohort), we aimed to establish an AVA/ H threshold that would be equivalent to 1.0 cm2 for defining severe AS. In a distinct prospective validation cohort of 395 patients, we compared the predictive accuracy of AVA/BSA and AVA/ H. Correlations between AVA and AVA/BSA or AVA/ H were excellent (all R 2 > 0.79) but greater with AVA/ H. Regressions lines were markedly different in obese and non-obese patients with AVA/BSA (P  < 0.0001) but almost identical with AVA/ H (P  = 0.16). AVA/BSA values that corresponded to an AVA of 1.0 cm2 were markedly different in obese and non-obese patients (0.48 and 0.59 cm2/m2) but not with AVA/ H (0.61 cm2/m for both). Agreement for the diagnosis of severe AS (AVA < 1 cm2) was significantly higher with AVA/ H than with AVA/BSA (P  < 0.05). Similar results were observed across the three countries. An AVA/ H cut-off value of 0.6 cm2/m [HR = 8.2(5.6–12.1)] provided the best predictive value for the occurrence of AS-related events [absolute AVA of 1 cm2: HR = 7.3(5.0–10.7); AVA/BSA of 0.6 cm2/m2 HR = 6.7(4.4–10.0)]. Conclusion In a large multinational/multiracial cohort, AVA/ H was better correlated with AVA than AVA/BSA and a cut-off value of 0.6 cm2/m provided a better diagnostic and prognostic value than 0.6 cm2/m2. Our results suggest that severe AS should be defined as an AVA < 1 cm2 or an AVA/ H  < 0.6 cm2/m rather than a BSA-indexed value of 0.6 cm2/m2. [ABSTRACT FROM AUTHOR]

Up to 40% of patients with aortic stenosis (AS) harbor discordant Doppler-echocardiographic findings, the most common of which is the presence of a small aortic valve area (≤1.0 cm 2 ) suggesting severe AS, but a low gradient (<40 mm Hg) suggesting nonsevere AS. The purpose of this paper is to present the role of multimodality imaging in the diagnostic and therapeutic management of this challenging entity referred to as low-gradient AS . Doppler-echocardiography is critical to determine the subtype of low-gradient AS: that is, classical low-flow, paradoxical low-flow, or normal-flow. Patients with low-flow, low-gradient AS generally have a worse prognosis compared with patients with high-gradient or with normal-flow, low-gradient AS. Patients with low-gradient AS and evidence of severe AS benefit from aortic valve replacement (AVR). However, confirmation of the presence of severe AS is particularly challenging in these patients and requires a multimodality imaging approach including low-dose dobutamine stress echocardiography and aortic valve calcium scoring by multidetector computed tomography. Transcatheter AVR using a transfemoral approach may be superior to surgical AVR in patients with low-flow, low-gradient AS. Further studies are needed to confirm the best valve replacement procedure and prosthetic valve for each category of low-gradient AS and to identify patients with low-gradient AS in whom AVR is likely to be futile. [ABSTRACT FROM AUTHOR]

Background: Left ventricular global longitudinal strain (LVLS) is a powerful predictor of outcome in patients with low-flow, low-gradient aortic stenosis (LF-LG AS) and low LV ejection fraction (LVEF). However, the impact of right ventricular (RV) function on the outcome of these patients remains unknown.Objectives: The aim of this study was to examine the impact of RV function as evaluated by RV free wall longitudinal strain (RVLS) on mortality in patients with LF-LG AS and low LVEF.Methods: 211 patients with LF-LG AS (mean gradient < 40 mm Hg and indexed aortic valve area (AVA) ≤ 0.6 cm²/m²) and low LVEF (≤ 40%)) were prospectively recruited in the True or Pseudo-severe Aortic Stenosis study. AS severity was assessed using the projected AVA (AVAproj) at normal flow rate. Among the 211 patients, 128 had RVLS measurement available at rest and were included in this analysis. RVLS measurement at dobutamine stress echocardiography (DSE) was available in 58 of the 128 patients.Results: Two-year survival was lower in patients with RVLS < |13|% (53% ± 9%) compared with those with RVLS > |13|% (69% ± 5%) (p = 0.04). In multivariable Cox analysis stratified for the type of treatment (aortic valve replacement vs conservative) and adjusted for age, AS severity, previous myocardial infarction and LVLS, rest RVLS < |13|% (HR = 2.70; 95% CI 1.19 to 6.11; p = 0.018) was independently associated with all-cause mortality. RVLS had incremental prognostic value over baseline risk factors and LVLS (χ² = 20.13 vs 13.56; p = 0.01). Reduced stress RVLS was also associated with increased risk of mortality (stress RVLS <| 14|%: HR = 2.98; 95% CI 1.30 to 6.52; p = 0.01). In multivariable Cox analysis, stress RVLS < |14|% remained independently associated with mortality (HR = 2.94; 95% CI 1.23 to 7.02; p = 0.015). After further adjustment for rest RVLS, stress RVLS < |14|% remained independently associated with mortality (HR = 3.29; 95% CI 1.17 to 9.25; p = 0.024), whereas rest RVLS was not (p > 0.05).Conclusions: In this series of patients with LF-LG AS and low LVEF, reduced RVLS was independently associated with increased risk of mortality. Furthermore, stress RVLS provided incremental prognostic value beyond that obtained from rest RVLS. Thus, RVLS measurement at rest and at DSE may be helpful to enhance risk stratification in this high-risk population.Trial Registration Number: NCT01835028; Results. [ABSTRACT FROM AUTHOR]

Background: The indications for tricuspid valve repair in the setting of mitral valve disease and concomitant tricuspid regurgitation (TR) remain unclear. We examined patients undergoing mitral valve replacement (MVR) to determine the effect of TR and tricuspid valve repair on survival, functional status, and postoperative TR. Methods: Between 1990 and 2005, 624 patients underwent MVR. Data included detailed serial echocardiographic tricuspid valve measurements, functional status, and survival data. Preoperative TR exceeded 2+ in 231: 125 received tricuspid repair and MVR, whereas 106 received MVR alone. Clinical and echocardiographic follow-up were complete (average, 6.8 ± 4.8 years). Parametric and semi-parametric tests were used to analyze outcomes. Results: TR exceeding 2+ at operation was associated with a 53% increase in late death (p = 0.003). Tricuspid repair prevented echocardiographic progression of TR and improved congestive heart failure symptoms (both p < 0.01). Overall survival did not improve (p = 0.3). A trend to worsening TR in patients was noted with a larger tricuspid annulus diameter and without significant (≤ 1+) TR preoperatively (odds ratio, 1.4 per cm increase in annulus diameter; p = 0.5), but this was not associated with worse functional or vital outcomes. Conclusions: In patients undergoing MVR, tricuspid repair is indicated when TR exceeds 2+ to alleviate heart failure symptoms, but without significantly improving survival in this population. TR of 2+ or less may not require repair. Echocardiographic tricuspid annular dimensions alone, in the absence of significant (≤ 1+) TR preoperatively, should not dictate the performance of tricuspid repair. [Copyright &y& Elsevier]

Background: Low rest transaortic flow rate (FR) has been shown previously to predict mortality in low-gradient aortic stenosis. However limited prognostic data exists on stress FR during low-dose dobutamine stress echocardiography. We aimed to assess the value of stress FR for the detection of aortic valve stenosis (AS) severity and the prediction of mortality. Methods: This is a multicenter cohort study of patients with reduced left ventricular ejection fraction and low-gradient aortic stenosis (aortic valve area <1 cm2 and mean gradient <40 mm Hg) who underwent low-dose dobutamine stress echocardiography to identify the AS severity and presence of flow reserve. The outcome assessed was all-cause mortality. Results: Of the 287 patients (mean age, 75+/-10 years; males, 71%; left ventricular ejection fraction, 31+/-10%) over a mean follow-up of 24+/-30 months there were 127 (44.3%) deaths and 147 (51.2%) patients underwent aortic valve intervention. Higher stress FR was independently associated with reduced risk of mortality (hazard ratio, 0.97 [95% CI, 0.94-0.99]; P =0.01) after adjusting for age, chronic kidney disease, heart failure symptoms, aortic valve intervention, and rest left ventricular ejection fraction. The minimum cutoff for prediction of mortality was stress FR 210 mL/s. Following adjustment to the same important clinical and echocardiographic parameters, among the three criteria of AS severity during stress, ie, the guideline definition of aortic valve area <1cm2 and aortic valve mean gradient >=40 mm Hg, or aortic valve mean gradient >=40 mm Hg, or the novel definition of aortic valve area <1 cm2 at stress FR >=210 mL/s, only the latter was independently associated with mortality (hazard ratio, 1.72 [95% CI, 1.05-2.82]; P =0.03). Furthermore aortic valve area <1cm2 at stress FR >=210 mL/s was the only severe aortic stenosis criterion that was associated with improved outcome following aortic valve intervention (P <0.001).> Conclusions: Stress FR during low-dose dobutamine stress echocardiography was useful for the detection of both AS severity and flow reserve and was associated with improved prediction of outcome following aortic valve intervention. [ABSTRACT FROM AUTHOR]

Studies echocardiographic volume flow and stenosis severity measures with changing flow rate in aortic stenosis. Noninvasive echo-Doppler measures of transvalvular volume of flow rate; Stenosis severity during progressive disease evolution.

This study was designed to investigate the dynamic nature of aortic annulus size during the cardiac cycle and to assess the utility of two-dimensional (2D) echocardiographic measurement of annulus diameter in predicting the surgeon's choice of prosthesis size. Preoperative measurements of aortic annulus diameter at end-diastole and mid-systole were compared with implanted prosthesis size in 26 patients. Annulus diameters were larger at mid-systole than end-diastole in all patients (24 ± 3 mm vs. 22 ± 3 mm; P < 0.0001). Both end-diastolic and mid-systolic diameters correlated with the surgeon's choice of prosthesis size (r = 0.74 and 0.71, respectively). However, prosthesis size was underestimated slightly by end-diastolic diameter (1 ± 2 mm; P = 0.03), and overestimated slightly by mid-systolic diameter (1 ± 2 mm; P = 0.01). The 95% limits of agreement for prosthetic size was -3 to +5 mm for enddiastolic diameter, or -5 to +3 mm for mid-systolic diameter. Averaging end-diastolic and mid-systolic diameters resulted in no bias with 95% limits of agreement of ± 4 mm of the averaged diameter. Patients with a small annulus dimension (end-diastole ≤ 20 mm; mid-systole ≤ 22 mm) have a high probability (86% and 78%, respectively) of requiring a small prosthesis (≤ 21 mm). [ABSTRACT FROM PUBLISHER]

Objectives We sought to assess the effect of 2 contemporary pericardial valves on left ventricular mass regression and clinical outcomes after aortic valve replacement (AVR) in patients with aortic stenosis (AS). Methods Patients were followed postoperatively in a dedicated valve clinic. A propensity score was derived for each patient and used to adjust all analyses. Longitudinal analysis was performed using a repeated measures growth curve model. Survival analysis was assessed with a Cox proportional hazards model. Results Since February 2011, 258 patients with AS and left ventricular hypertrophy underwent AVR with the Trifecta (TR) (St Jude Medical, St Paul, Minn) or Perimount Magna Ease (ME) (Edwards LifeSciences, Irvine, Calif) bioprosthesis. There were longer bypass and crossclamp times and the indexed left ventricular outflow tract was smaller in the TR group. For the TR and ME, respectively, peak (14.4 ± 5.1 mm Hg vs 20.9 ± 7.2 mm Hg; P < .001) and mean (7.3 ± 2.7 mm Hg vs 10.9 ± 4.3 mm Hg; P < .001) gradients were significantly smaller postoperatively in the TR group. There was greater total mass regression (44.3 g/m 2 ; 95% confidence interval [CI], 36.3-52.3 vs 29.5; 95% CI, 20.4-38.5 g/m 2 ; P = .020) and mass regression over time in the TR group compared with the ME group ( P = .016). Freedom from readmission, congestive heart failure, and the composite outcome of all-cause mortality, readmission, and congestive heart failure at 2.5 years was significantly improved in the TR group (composite outcome in TR and ME groups, respectively, 90.2; 95% CI, 81.9-94.9 and 78.2; 95% CI, 67.1-86.0; P = .013) Conclusions TR use was associated with significantly increased left ventricular mass regression and improved intermediate-term clinical outcome in patients with left ventricular hypertrophy undergoing AVR for AS, compared with use of the ME. [ABSTRACT FROM AUTHOR]

Background: New-onset or worsening heart failure is the most common extra-pulmonary complication of community-acquired pneumonia (CAP) during the first 30 days after diagnosis.Methods: We evaluated the changes in the right ventricular function amongst adult CAP survivors from the time of acute infection to its resolution. We performed comprehensive transthoracic echocardiographic examinations to assess right heart function during the acute illness and the convalescent period (4 to 6 weeks after hospital discharge).Results: Twenty-six patients underwent acute measurements, of which convalescent measurements were completed in 19 subjects. There was no significant change in any of the right heart function parameters from the acute to convalescent stage of CAP.Conclusions: Our results suggest that right ventricular function does not meaningfully change in the transition from the acute to convalescent stage of CAP in non-critically ill adult CAP survivors. [ABSTRACT FROM AUTHOR]

Background: In the American College of Cardiology/American Heart Association guidelines, patients are considered to have true-severe stenosis when the mean gradient (MG) is ≥40 mm Hg with an aortic valve area (AVA) ≤1 cm2 during dobutamine stress echocardiography (DSE). However, these criteria have not been previously validated.Objectives: The aim of this study was to assess the value of these criteria to predict the presence of true-severe AS and the occurrence of death in patients with low-flow, low-gradient aortic stenosis (LF-LG AS).Methods: One hundred eighty-six patients with low left ventricular ejection fraction (LVEF) LF-LG AS were prospectively recruited and underwent DSE, with measurement of the MG, AVA, and the projected AVA (AVAProj), which is an estimate of the AVA at a standardized normal flow rate. Severity of AS was independently corroborated by macroscopic evaluation of the valve at the time of valve replacement in 54 patients, by measurement of the aortic valve calcium by computed tomography in 25 patients, and by both methods in 8 patients. According to these assessments, 50 of 87 (57%) patients in the study cohort had true-severe stenosis.Results: Peak stress MG ≥40 mm Hg, peak stress AVA ≤1 cm2, and the combination of peak stress MG ≥40 mm Hg and peak stress AVA ≤1 cm2 correctly classified AS severity in 48%, 60%, and 47% of patients, respectively, whereas AVAProj ≤1 cm2 was better than all the previous markers (p < 0.007), with 70% correct classification. Among the subset of 88 patients managed conservatively (47% of the cohort), 52 died during a follow-up of 2.8 ± 2.5 years. After adjustment for age, sex, functional capacity, chronic kidney failure, and peak stress LVEF, peak stress MG and AVA were not predictors of mortality in this subset. In contrast, AVAProj ≤1 cm2 was a strong predictor of mortality under medical management (hazard ratio: 3.65; p = 0.0003).Conclusions: In patients with low LVEF LF-LG AS, the DSE criteria of a peak stress MG ≥40 mm Hg, or the composite of a peak stress MG ≥40 mm Hg and a peak stress AVA ≤1 cm2 proposed in the guidelines to identify true-severe AS and recommend valve replacement, have limited value to predict actual stenosis severity and outcomes. In contrast, AVAProj better distinguishes true-severe AS from pseudo-severe AS and is strongly associated with mortality in patients under conservative management. (Multicenter Prospective Study of Low-Flow Low-Gradient Aortic Stenosis [TOPAS]; NCT01835028). [ABSTRACT FROM AUTHOR]

Background--Heart failure with reduced ejection fraction and obstructive sleep apnea (OSA), 2 states of increased metabolic demand and sympathetic nervous system activation, often coexist. Continuous positive airway pressure (CPAP), which alleviates OSA, can improve ventricular function. It is unknown whether this is due to altered oxidative metabolism or presynaptic sympathetic nerve function. We hypothesized that short-term (6-8 weeks) CPAP in patients with OSA and heart failure with reduced ejection fraction would improve myocardial sympathetic nerve function and energetics. Methods and Results--Forty-five patients with OSA and heart failure with reduced ejection fraction (left ventricular ejection fraction 35.8±9.7% [mean±SD]) were evaluated with the use of echocardiography and 11C-acetate and 11C-hydroxyephedrine positron emission tomography before and ≈6 to 8 weeks after randomization to receive short-term CPAP (n=22) or no CPAP (n=23). Work metabolic index, an estimate of myocardial efficiency, was calculated as follows: (stroke volume indexxheart ratexsystolic blood pressure÷Kmono), where Kmono is the monoexponential function fit to the myocardial 11C-acetate time-activity data, reflecting oxidative metabolism. Presynaptic sympathetic nerve function was measured with the use of the 11C-hydroxyephedrine retention index. CPAP significantly increased hydroxyephedrine retention versus no CPAP (Δretention: +0.012 [0.002,0.021] versus -0.006 [-0.013, 0.005] min-1; P=0.003). There was no significant change in work metabolic index between groups. However, in those with more severe OSA (apnea-hypopnea index >20 events per hour), CPAP significantly increased both work metabolic index and systolic blood pressure (P<0.05). Conclusions--In patients with heart failure with reduced ejection fraction and OSA, short-term CPAP increased hydroxyephedrine retention, indicating improved myocardial sympathetic nerve function, but overall did not affect energetics. In those with more severe OSA, CPAP may improve cardiac efficiency. Further outcome-based investigation of the consequences of CPAP is warranted. [ABSTRACT FROM AUTHOR]