Cost-effectiveness of population screening for aortic stenosis

BACKGROUND AND AIMS

Aortic stenosis (AS) is a progressive disease predominantly affecting elderly patients that carries significant morbidity and mortality without aortic valve replacement, the only proven treatment. Our objective was to determine the cost-effectiveness of AS screening using transthoracic echocardiography (TTE) in a geriatric population from the perspective of the publicly funded healthcare system in Canada.

METHODS

Markov models estimating the cost-effectiveness ratio (ICER) for AS screening with a one-time TTE were developed. The model included diagnosed and undiagnosed AS health states, hospitalizations, TAVR and post-TAVR health states. Primary analysis included screening at 70 and 80 years of age with intervention at symptom onset, with scenario analysis included for early intervention at the time of severe asymptomatic AS diagnosis. Monte Carlo simulation of 5000 replications was completed with a lifetime horizon and 1.5% discount for costs and outcomes.

RESULTS

Screening for AS at the age of 70 years was associated with an ICER of $156,722 and screening at 80 years of age was associated with an ICER of $28,005, suggesting that screening at 80 years of age is cost-effective when willingness-to-pay per QALY is $50,000. Scenario analysis with early intervention was not cost-effective with an ICER of $142,157 at 70 years, and $124,651 at 80 years.

CONCLUSION

Screening for AS at 80 years of age with a one-time TTE, in a Canadian population, improves quality of life and is cost-effective in a publicly funded healthcare system providing TAVR is reserved for symptomatic patients.

Aortic valve replacement for aortic stenosis: Influence of centre volume on TAVR adoption rates and outcomes in France

BACKGROUND

Transcatheter (TAVR) has supplanted surgical (SAVR) aortic valve replacement (AVR).

AIM

To evaluate whether adoption of this technology has varied according to centre volume at the nationwide level.

METHODS

From an administrative hospital-discharge database, we collected data on all AVRs performed in France between 2007 and 2019. Centres were divided into terciles based on the annual number of SAVRs performed in 2007-2009 ("before TAVR era").

RESULTS

A total of 192,773 AVRs (134,662 SAVRs and 58,111 TAVRs) were performed in 47 centres. The annual number of AVRs and TAVRs increased significantly and linearly in low-volume (<152 SAVRs/year; median 106, interquartile range [IQR] 75-129), middle-volume (152-219 SAVRs/year; median 197, IQR 172-212) and high-volume (>219 SAVRs/year; median 303, IQR 268-513) terciles, but to a greater degree in the latter (+14, +16 and +24 AVRs/centre/year and +16, +19 and +31 TAVRs/centre/year, respectively; PANCOVA<0.001). Charlson Comorbidity Index and in-hospital death rates declined from 2010 to 2019 in all terciles (all Ptrend<0.05). In 2017-2019, after adjusting for age, sex and Charlson Comorbidity Index, there was a trend toward lower death rates in the high-volume tercile (P=0.06) for SAVR, whereas death rates were similar for TAVR irrespective of tercile (P=0.27). Similar results were obtained when terciles were defined based on number of interventions performed in the last instead of the first 3years. Importantly, even centres in the lowest-volume tercile performed a relatively high number of interventions (150 TAVRs/year/centre).

CONCLUSIONS

In a centralized public healthcare system, the total number of AVRs increased linearly between 2007 and 2019, mostly due to an increase in TAVR, irrespective of centre volume. Progressive declines in patient risk profiles and death rates were observed in all terciles; in 2017-2019 death rates were similar in all terciles, although lower in high-volume centres for SAVR.

Edge-to-edge with partial band mitral valve repair compared to replacement and undersized restrictive annuloplasty for ischemic mitral regurgitation

Objective

Evidence supports replacement over repair for ischemic mitral regurgitation due to improved durability; however, the latter often involves an undersized ring annuloplasty that does not include edge-to-edge approximation. The objective of this study was to evaluate the outcomes of replacement, edge-to-edge leaflet approximation with mild-undersized annuloplasty and undersized ring annuloplasty for ischemic mitral regurgitation.

Methods

This is a single-center retrospective study of patients undergoing mitral surgery for moderate-severe or greater ischemic mitral regurgitation, between 2004 and 2020, with mild-undersized annuloplasty, mitral valve replacement, or undersized restrictive annuloplasty (undersized ring annuloplasty). The primary outcome was all-cause mortality. Secondary outcomes included first recurrence of mitral regurgitation, heart failure hospitalization, and composite of valve-related events (bleeding, thromboembolism, endocarditis, and mitral valve reoperation).

Results

There were 121, 93, and 78 patients in the mitral valve replacement, mild-undersized annuloplasty, and undersized restrictive annuloplasty groups, respectively, with a median follow-up of 3.1, 5.9, and 3.8 years, respectively. Both mitral valve replacement (hazard ratio, 1.87; 95% CI, 1.029-3.415) and undersized restrictive annuloplasty (hazard ratio, 2.73; 95% CI, 1.480-5.061) were associated with worse survival compared with mild-undersized annuloplasty. At 2 years, the rate of mild-moderate mitral regurgitation was greater in the mild-undersized annuloplasty group compared with the mitral valve replacement group (P = .001) but less than in the undersized restrictive annuloplasty group (P = .001). The rate of recurrent moderate or greater mitral regurgitation at 2 years was similar between mild-undersized annuloplasty and mitral valve replacement groups but significantly higher after undersized restrictive annuloplasty (P < .0001). Mitral valve replacement and undersized restrictive annuloplasty were associated with a significant increase in the incidence of first heart failure hospitalization compared with mild-undersized annuloplasty (P < .001 and P = .001, respectively). Mitral valve replacement was associated with an increased incidence of valve-related events compared with mild-undersized annuloplasty (P = .002).

Conclusions

Surgical edge-to-edge approximation in addition to a mild-undersizing annuloplasty offers similar durability compared with replacement, with a lower rate of hospitalization for heart failure, and may confer a survival advantage.

Impact of the coronavirus disease 2019 pandemic on aortic valve replacement and outcomes in France

BACKGROUND

The coronavirus disease of 2019 (COVID-19) pandemic lockdowns limited access to medical care. The impact on surgical (SAVR) and transcatheter (TAVR) aortic valve replacement (AVR) has been poorly described.

AIM

We sought to evaluate the impact of the COVID-19 pandemic on the number and modalities of AVR, patient demographics and in-hospital outcomes at the nationwide level.

METHODS

Using the French nationwide administrative hospital discharge database, we compared projected numbers and proportions of AVR and hospital outcomes, obtained using linear regressions derived from 2015-2019 trends, with those observed in 2020.

RESULTS

In 2020, 21,382 AVRs were performed (13,051 TAVRs, 5706 isolated SAVRs and 2625 SAVRs combined with other cardiac surgery). Compared with the 2020 projected number of AVRs (24,586, 95% confidence interval [CI] 23,525-25,646), TAVRs (14,866, 95% CI 14,164-15,568), isolated SAVRs (6652, 95% CI 6203-7100) and SAVRs combined with other cardiac surgery (3069, 95% CI 2822-3315), there were reductions of 13.0%, 12.2%, 14.2% and 14.5%, respectively. These trends were similar regardless of sex or age. In 2020, the mean age, Charlson Comorbidity Index and hospital admission duration continued to decline, and the proportion of females remained constant, following 2015-2019 trends. Overall, 2020 in-hospital mortality was higher than projected (2.0% observed vs. 1.7% projected; 95% CI 1.5-1.9%), with no increased pacemaker implantation, but more acute kidney injury and cerebrovascular accidents in some surgical subsets.

CONCLUSIONS

During the COVID-19 pandemic, fewer TAVR and SAVR procedures were performed, with increased in-hospital mortality and periprocedural complications. Extended follow-up will be important to establish the long-term effect of the COVID-19 pandemic on patient management and outcomes.

The Prevalence and Characteristics of Arrhythmic Mitral Valve Prolapse in Patients With Unexplained Cardiac Arrest

BACKGROUND

There is growing evidence that mitral valve prolapse (MVP) is associated with otherwise unexplained cardiac arrest (UCA). However, reports are hindered by the absence of a systematic ascertainment of alternative diagnoses.

OBJECTIVES

This study reports the prevalence and characteristics of MVP in a large cohort of patients with UCA.

METHODS

Patients were enrolled following an UCA, defined as cardiac arrest with no coronary artery disease, preserved left ventricular ejection fraction, and no apparent explanation on electrocardiogram. A comprehensive evaluation was performed, and patients were diagnosed with idiopathic ventricular fibrillation (IVF) if no cause was found. Echocardiography reports were reviewed for MVP. Patients with MVP were divided into 2 groups: those with IVF (AMVP) and those with an alternative diagnosis (nonarrhythmic MVP). Patient characteristics were then compared. The long-term outcomes of AMVP were reported.

RESULTS

Among 571 with an initially UCA, 34 patients had MVP (6%). The prevalence of definite MVP was significantly higher in patients with IVF than those with an alternative diagnosis (24 of 366 [6.6%] vs 5 of 205 [2.4%]; P = 0.03). Bileaflet prolapse was significantly associated with AMVP (18 of 23 [78%] vs 1 of 8 [12.5%]; P = 0.001; OR: 25.2). The proportion of patients with AMVP who received appropriate implantable cardioverter-defibrillator therapies over a median follow-up of 42 months was 21.1% (4 of 19).

CONCLUSIONS

MVP is associated with otherwise UCA (IVF), with a prevalence of 6.6%. Bileaflet prolapse appears to be a feature of AMVP, although future studies need to ascertain its independent association. A significant proportion of patients with AMVP received appropriate implantable cardioverter-defibrillator therapies during follow-up.

Association of Age and Sex With Use of Transcatheter Aortic Valve Replacement in France

BACKGROUND

Current guidelines recommend selecting surgical aortic valve replacement (SAVR) or transcatheter aortic valve replacement (TAVR) based on age, comorbidities, and surgical risk. Nevertheless, reports from the United States suggest a rapid expansion of TAVR in young patients.

OBJECTIVES

The authors sought to evaluate the trends in TAVR uptake at a nationwide level in France according to age and sex.

METHODS

Using a nationwide administrative database, we evaluated age- and sex-related trends in TAVR uptake, patient demographics, and in-hospital outcomes between 2015 and 2020.

RESULTS

A total of 107,397 patients (44.0% female) underwent an isolated aortic valve replacement (AVR) (59.1% TAVR, 40.9% SAVR). In patients <65 years of age, the proportion of TAVR increased by 63.2% (P < 0.001) from 2015 to 2020 but remained uncommon at 11.1% of all AVR by 2020 (12.4% in females, 10.6% in males) while TAVR was the dominant modality in patients ≥65 years of age. In patients undergoing TAVR, the Charlson comorbidity index (CCI) (P = 0.119 for trend) and in-hospital mortality (P = 0.740 for trend) remained unchanged in patients <65 years of age but declined in those ≥65 years of age irrespective of sex (all P < 0.001 for trends). Females were older (P < 0.001), had lower CCI (P < 0.001), were more likely to undergo TAVR (P < 0.001), and experienced higher in-hospital mortality (TAVR, P = 0.015; SAVR, P < 0.001) that persisted despite adjustment for age and CCI.

CONCLUSIONS

In France, the use of TAVR remained uncommon in young patients, predominantly restricted to those at high risk. Important sex differences were observed in patent demographics, selection of AVR modality, and patient outcomes. Additional research evaluating the long-term impact of TAVR use in young patients and prospective data evaluating sex differences in AVR modality selection and outcomes are needed.

Arrhythmic Mitral Valve Prolapse: Risk Assessment and Management

Arrhythmic mitral valve prolapse (MVP) has gained great interest recently because of the increasing recognition of its potential role in unexplained cardiac arrest. Although evidence has accumulated to show the association of arrhythmic MVP (AMVP) with sudden cardiac death (SCD), risk stratification and management remain unclear. Physicians are faced with the challenges of screening for AMVP among MVP patients and the dilemma of when and how to intervene to prevent SCD in these patients. In addition, there is little guidance to help approach MVP patients who present with an otherwise unexplained cardiac arrest to know whether MVP was the primary cause of cardiac arrest or just an innocent bystander. Herein we review the epidemiology and definition of AMVP, the risk and mechanisms of SCD, and summarize the clinical evidence behind risk markers of SCD and therapeutic interventions that could potentially prevent it. We also propose an algorithm that provides guidance as to how to screen for AMVP and what therapeutic interventions to use. Last, we propose a diagnostic algorithm for approaching patients with otherwise unexplained cardiac arrest who are shown to have MVP.

Unmet needs in valvular heart disease

Valvular heart disease (VHD) is the next epidemic in the cardiovascular field, affecting millions of people worldwide and having a major impact on health care systems. With aging of the population, the incidence and prevalence of VHD will continue to increase. However, VHD has not received the attention it deserves from both the public and policymakers. Despite important advances in the pathophysiology, natural history, management, and treatment of VHD including the development of transcatheter therapies, VHD remains underdiagnosed, identified late, and often undertreated with inequality in access to care and treatment options, and there is no medication that can prevent disease progression. The present review article discusses these gaps in the management of VHD and potential actions to undertake to improve the outcome of patients with VHD.

Aortic Stenosis Progression: A Systematic Review and Meta-Analysis

BACKGROUND

Aortic valve stenosis is a progressive disorder with variable progression rates. The factors affecting aortic stenosis (AS) progression remain largely unknown.

OBJECTIVES

This systematic review and meta-analysis sought to determine AS progression rates and to assess the impact of baseline AS severity and sex on disease progression.

METHODS

The authors searched Medline, Embase, and the Cochrane Central Register of Controlled Trials from inception to July 1, 2020, for prospective studies evaluating the progression of AS with the use of echocardiography (mean gradient [MG], peak velocity [PV], peak gradient [PG], or aortic valve area [AVA]) or computed tomography (calcium score [AVC]). Random-effects meta-analysis was performed to evaluate the rate of AS progression for each parameter stratified by baseline severity, and meta-regression was performed to determine the impact of baseline severity and of sex on AS progression rate.

RESULTS

A total of 24 studies including 5,450 patients (40% female) met inclusion criteria. The pooled annualized progression of MG was +4.10 mm Hg (95% CI: 2.80-5.41 mm Hg), AVA -0.08 cm² (95% CI: 0.06-0.10 cm²), PV +0.19 m/s (95% CI: 0.13-0.24 m/s), PG +7.86 mm Hg (95% CI: 4.98-10.75 mm Hg), and AVC +158.5 AU (95% CI: 55.0-261.9 AU). Increasing baseline severity of AS was predictive of higher rates of progression for MG (P < 0.001), PV (P = 0.001), and AVC (P < 0.001), but not AVA (P = 0.34) or PG (P = 0.21). Only 4 studies reported AS progression stratified by sex, with only PV and AVC having 3 studies to perform a meta-analysis. No difference between sex was observed for PV (P = 0.397) or AVC (P = 0.572), but the level of confidence was low.

CONCLUSIONS

This study provides progression rates for both hemodynamic and anatomic parameters of AS and shows that increasing hemodynamic and anatomic baseline severity is associated with faster AS progression. More studies are needed to determine if sex differences affect AS progression. (Aortic Valve Stenosis Progression Rate: A Systematic Review and Meta-Analysis; CRD42021207726).

Metabolic activity of the left and right atria are differentially altered in patients with atrial fibrillation and LV dysfunction

BACKGROUND

Alterations in atrial metabolism may play a role in the perpetuation of atrial fibrillation (AF). This study sought to compare 18F-fluorodeoxyglucose (FDG) uptake on PET, in patients with LV dysfunction versus those without AF.

METHODS

Seventy-two patients who underwent myocardial viability assessment were evaluated. AF patients (36) had persistent or permanent AF based on history and ECG. Patients without AF (36) were matched to AF patients based on sex, diabetes, age, and LVEF. Maximum and mean FDG Standard Uptake Values (SUV) in the left atrial (LA) wall and right atrial (RA) wall were measured. Tissue-to-blood ratios (TBR) were calculated as atrial wall to blood-pool activity. Atrial volumes were measured by echocardiography.

RESULTS

Maximum and mean FDG SUV and TBRs were significantly increased in the RA (but not the LA) of patients with AF compared to those without (P < 0.01). When accounting for changes in atrial volume, the presence of AF remained a significant predictor of higher RAMAX, but not RAMEAN FDG uptake.

CONCLUSION

In patients with LV dysfunction from ischemic cardiomyopathy, LA and RA glucose metabolism are differentially altered in those with persistent atrial fibrillation. Further investigations should elucidate the temporal relationship between AF and glucose metabolic changes, as a potential target for therapy.

Aortic valve replacement for aortic stenosis in France – influence of centers' volumes on TAVR adoption rate and outcomes

Aims

Over the last decade, transcatheter aortic valve replacement (TAVR) became extensively used, now being the recommended as first line procedure for aortic valve replacement (AVR) in selected patients' populations. It is unknown whether TAVR adoption rate and variability in outcomes is influenced by centers' volume.

Methods

From a French administrative hospital-discharge database, we collected all AVR performed in France between 2007 and 2019. Centers were stratified to terciles based on their annual SAVR per year per center during 2007–2009 (“pre TAVR era”).

Results

There was 218,489 AVRs (153,747 SAVR and 74,732 TAVR) performed in 46 centers between 2007–2019. Number of total AVR and even more so number of number of TAVR significantly and linearly increased from 2007 to 2019 in all terciles but faster in the high volume tercile (+17, +17 and +31 AVR/center/year in the low, middle and high terciles respectively, P [ANCOVA]&lt;0.001; +11, + 19 and +33 TAVR/center/year in the low, medium and high tercile respectively, P [ANCOVA] &lt;0.00, Figure 1). The age of patients underwent TAVR remained grossly unchanged in all three terciles, however, the Charlson index declined from 2010 to 2019 (from 1.35±1.42 to 0.65±1.04, from 1.21±1.40 to 0.65±1.05 and from 1.53±1.58 to 0.81±1.21, in the low, middle and high terciles, P for trend &lt;0.001, 0.021, and &lt;0.001, respectively). Charlson score in the years 2017–2019, was higher in the high than middle and low terciles (0.87±1.22, 0.76±1.11 and 0.65±1.04, respectively, P&lt;0.0001). The in-hospital mortality rate for TAVR significantly declined from 2010 to 2019 for TAVR in all terciles (from 8.3% to 2.1%, from 7.5% to 2.5% and from 8.2% to 2.1% for low, middle and high TAVR terciles, respectively; p for trend = 0.002, 0.001 and &lt;0.001, respectively, Figure 2). Average mortality in 2017–2019 was similar in all terciles (2.3%, 2.5% and 2.2% for low, middle and high terciles, respectively, P=0.47). After adjusting for age, sex and Charlson score, mortality was higher in the low tercile compared with middle and high terciles (OR 1.15, P&lt;0.001, confidence interval [CI] 1.0–1.2, and OR 1.18, P&lt;0.001, CI 1.1–1.2, respectively).

Conclusions

From 2007 to 2019 total AVR linearly increased, mostly due to increase in TAVR, irrespective of centers' volume, but increase rate was higher in high volume centers. A constant decline in patients risk profile, with a striking decrease in mortality rate, was observed in all volume terciles. High-volume centers patients' have higher risk profile, with adjusted mortality slightly lower than medium and low volume centers.

Funding Acknowledgement

Type of funding sources: None.

Natural History of Mitral Annulus Calcification and Calcific Mitral Valve Disease

BACKGROUND

The natural history of mitral annular calcification (MAC) and risk for developing calcific mitral valve disease (CMVD) has been poorly defined. We sought to evaluate the progression rate of MAC and of the development of CMVD.

METHODS

Patients with MAC and paired echocardiograms at least one year apart between 2005 and 2019 were included. Progression rates from mild/moderate to severe MAC and to CMVD (defined as severe MAC and significant mitral stenosis and/or regurgitation) were assessed, along with potential association with sex.

RESULTS

A total of 11,605 patients (73±10years, 51%male) with MAC (78% mild, 17% moderate, 5% severe) were included and had a follow up echocardiogram at 4.2±2.7years. In patients with mild/moderate MAC, 33% presented with severe MAC at 10 years. The rate of severe MAC was higher in females than in males (41% vs. 24%, P<0.001, HR=1.3, P<0.001) and in patients with moderate vs. mild MAC (71% vs. 22%, P<0.001, HR=6.1, P<0.001). At 10 years 10% presented with CMVD (4%, 23% and 60% in patients with mild, moderate, and severe MAC respectively) and was predicted by female sex (15% vs. 5%, P<0.0001), even after adjustment for MAC severity (HR=1.9, P<0.001).

CONCLUSION

In this large cohort of patients with MAC, progression to severe MAC was common and frequently results in CMVD. Female sex was associated with higher progression rates. MAC and CMVD are expected to dramatically increase as the population ages highlighting the importance of a better understanding of the pathophysiology of MAC in order to develop effective preventive medical therapies.

Increased myocardial oxygen consumption rates are associated with maladaptive right ventricular remodeling and decreased event-free survival in heart failure patients

BACKGROUND

Reduced left ventricular (LV) function is associated with increased myocardial oxygen consumption rate (MVO2) and altered sympathetic activity, the role of which is not well described in right ventricular (RV) dysfunction.

METHODS AND RESULTS

33 patients with left heart failure were assessed for RV function/size using echocardiography. Positron emission tomography (PET) was used to measure 11C-acetate clearance rate (kmono), 11C-hydroxyephedrine (11C-HED) standardized uptake value (SUV), and retention rate. RV MVO2 was estimated from kmono. 11C-HED SUV and retention indicated sympathetic neuronal function. A composite clinical endpoint was defined as unplanned cardiac hospitalization within 5 years. Patients with (n = 10) or without (n = 23) RV dysfunction were comparable in terms of sex (male: 70.0 vs 69.5%), LV ejection fraction (39.6 ± 9.0 vs 38.6 ± 9.4%), and systemic hypertension (70.0 vs 78.3%). RV dysfunction patients were older (70.9 ± 13.5 vs 59.4 ± 11.5 years; P = .03) and had a higher prevalence of pulmonary hypertension (60.0% vs 13.0%; P = .01). RV dysfunction was associated with increased RV MVO2 (.106 ± .042 vs .068 ± .031 mL/min/g; P = .02) and decreased 11C-HED SUV and retention (6.05 ± .53 vs 7.40 ± 1.39 g/mL (P < .001) and .08 ± .02 vs .11 ± .03 mL/min/g (P < .001), respectively). Patients with an RV MVO2 above the median had a shorter event-free survival (hazard ratio = 5.47; P = .01). Patients who died within the 5-year follow-up period showed a trend (not statistically significant) for higher RV MVO2 (.120 ± .026 vs .074 ± .038 mL/min/g; P = .05).

CONCLUSIONS

RV dysfunction is associated with increased oxygen consumption (also characterized by a higher risk for cardiac events) and impaired RV sympathetic function.

Trends in aortic valve replacement for aortic stenosis: a French nationwide study

AIMS

Transcatheter aortic valve replacement (TAVR) as an alternative to surgical aortic valve replacement (SAVR) has profoundly changed the management of patients with aortic valve stenosis (AS). Large unbiased nationwide data regarding TAVR implementation, impact on SAVR and their respective outcomes are scarce.

METHODS AND RESULTS

Based on a French administrative hospital-discharge database, we collected data on all consecutive aortic valve replacements (AVRs) performed in France for AS between 2007 and 2019 [106 253 isolated SAVR (49%), 46 514 combined SAVR (21%), and 65 651 TAVR (30%)]. The number of AVR linearly increased between 2007 and 2019 (from 10 892 to 23 109, P for trend < 0.0001) due to a marked increase in TAVR (from 253 to 13 030, P for trend < 0.0001), while SAVR increased up to 2013 and then declined (10 892 in 2007, 12 699 in 2013, and 10 079 in 2019). The Charlson index decreased linearly for TAVR, but in two steps for SAVR (2011 and 2017). In-hospital mortality rates of both SAVR and TAVR declined (both P for trend < 0.0001) and were similar or lower for TAVR than for isolated SAVR in patients 75 years or above in the last 3 years (2017-19). Complication rates of TAVR also declined but permanent pacemaker rates remained high and length of stay substantial (16.7% and median 6 days, respectively, in 2017-19).

CONCLUSION

The number of AVR has doubled in a decade and TAVR has become the dominant form of AVR in 2018. The improvement in patient profiles seems to have anticipated the demonstrated benefit of TAVR in intermediate and low-risk patients. In patients 75 years or older, TAVR should be considered as the first option. We also highlight two important areas for improvement, the high permanent pacemaker rates, and the long length of stay even in the contemporary era. Our results may have major implications for clinical practice and policymakers.

Clinical Value of Stress Transaortic Flow Rate During Dobutamine Echocardiography in Reduced Left Ventricular Ejection Fraction, Low-Gradient Aortic Stenosis: A Multicenter Study

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). Guideline-defined stroke volume flow reserve did not predict mortality.

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.

Size-adjusted aortic valve area: refining the definition of severe aortic stenosis

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 R2 > 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.

Clinical implications of left atrial size adjustment: Impact of obesity

BACKGROUND

American and European societies recommend using left atrial (LA) volume adjusted to body surface area (BSA) as the means of indexing LA volume to the patient's body size irrespective of morphometric characteristics.

AIM

To evaluate the impact of obesity on LA volume indexation to BSA on the presence and degree of LA enlargement.

METHODS

From our echocardiography database, we extracted all consecutive adults referred for a transthoracic echocardiography in 2019 (n=28,725; 64±17 years; 55% male; 31% obese [body mass index≥30kg/m²]). LA volume indexed to BSA was calculated using measured weight (LA_Meas) and ideal weight (LA_Ideal) calculated using the Devine Formula.

RESULTS

LA_Meas and LA_Ideal were 35±17mL/m² and 40±19mL/m², respectively (P<0.0001); 13% were classified as having a normal LA_Meas but LA_Ideal enlargement overall, 25% in obese patients and 7% in non-obese patients (P<0.0001). The percentages of patients with no, mild, moderate and severe LA dilatation were 57%, 19%, 9% and 16%, respectively, using LA_Meas, and 45%, 20%, 11% and 24%, respectively, using LA_Ideal (kappa=0.57). Degree of LA enlargement differed in 8194 patients (29%); 96% of the disagreement was related to underestimation of the degree of LA enlargement using LA_Meas. Agreement for the degree of LA enlargement was poor in obese and good in non-obese patients (kappa=0.28 and 0.71, respectively). As illustrative clinical implications, diastolic function grade was modified in 8.3% of patients with preserved ejection fraction and 10.8% of patients with reduced left ventricular ejection fraction/myocardial disease, and timing for intervention was potentially different in 12.9% of patients with primary mitral regurgitation.

CONCLUSIONS

Indexing LA volume to measured BSA versus ideal BSA markedly underestimates the presence and severity of LA enlargement, especially in obese patients, with potential important clinical implications.

Prognostic Value of Peak Exercise Systolic Pulmonary Arterial Pressure in Asymptomatic Primary Mitral Valve Regurgitation

BACKGROUND

The contribution of exercise echocardiography in primary asymptomatic mitral regurgitation (MR) remains debated. The aim of this study was to gain evidence regarding its usefulness in this setting and to investigate the prognostic value of peak exercise systolic pulmonary artery pressure (SPAP).

METHODS

One hundred seventy-seven patients (mean age, 56 ± 13 years; 69% men) with moderate to severe (grade 3+) or severe (grade 4+) degenerative MR and preserved left ventricular ejection fraction, in sinus rhythm, referred for clinically indicated exercise echocardiography were identified. The end point, MR-related events, was a composite of all-cause death or occurrence of symptoms, heart failure, atrial fibrillation, left ventricular ejection fraction < 60%, left ventricular end-systolic diameter ≥ 45 mm, or resting SPAP > 50 mm Hg.

RESULTS

At rest, effective regurgitant orifice area was 48 ± 16 mm², regurgitant volume 74 ± 26 mL, and SPAP 32 ± 7 mm Hg, and MR was severe in 138 patients (78%). Peak exercise SPAP was 55 ± 10 mm Hg. Positive results on exercise testing motivated surgery in 26 patients, 11 underwent prophylactic surgery, 10 were lost to follow-up, and 130 were included in the outcome analysis. During a follow-up period of 19 ± 7 months, 31 MR-related events (24%) were reported. Peak exercise SPAP was predictive of outcomes in univariate analysis (P = .01) and after adjustment for age, gender, MR severity, and resting SPAP (P < .05). Peak exercise SPAP ≥ 50 mm Hg was associated with worse event-free survival (hazard ratio, 5.24; 95% CI, 1.77-15.53; P = .003), but not the threshold of ≥60 mm Hg proposed in previous guidelines (hazard ratio, 1.70; 95% CI, 0.71-4.03; P = .24).

CONCLUSIONS

The present findings support the use of exercise echocardiography for risk stratification in patients with asymptomatic primary MR and suggest a lower peak exercise SPAP threshold (50 mm Hg) than previously recommended to define the timing of intervention. Prospective studies are needed to confirm these findings.

Management and Outcome of Patients Admitted With Tricuspid Regurgitation in France

BACKGROUND

Growing evidence shows a major outcome impact and undertreatment of tricuspid regurgitation (TR), but large and comprehensive contemporary reports of management and outcome at the nationwide level are lacking.

METHODS

We gathered all consecutive patients admitted with a diagnosis of likely functional TR in 2014-2015 in France from the Programme de Médicalisation des Systèmes d'Information national database and collected rate of surgery, in-hospital mortality, 1-year mortality, or heart failure (HF) readmission rates.

RESULTS

In 2014-2015, 17,676 consecutive patients (75 ± 14 years of age, 51% female) were admitted with a TR diagnosis. Charlson index was ≥ 2 in 56% of the population and 46% presented with HF. TR was associated with prior cardiac surgery, ischemic/dilated cardiomyopathy, or mitral regurgitation in 73% of patients. Only 10% of TR patients overall and 67% of those undergoing mitral valve surgery received a tricuspid valve intervention. Among the 13,654 (77%) conservatively managed patients, in-hospital mortality, 1-year mortality, and 1-year mortality or HF readmission rates were 5.1%, 17.8%, and 41%, respectively, overall, and 5.3%,17.2%, and 37%, respectively, among those with no underlying medical conditions (8-fold higher than predicted for age and gender).

CONCLUSIONS

This nationwide cohort of patients admitted with TR included elderly patients with frequent comorbidities/underlying cardiac diseases. In patients conservatively managed, mortality and morbidity were considerably high over a short time span. Despite this poor prognosis, only 10% of patients underwent a tricuspid valve intervention. These nationwide data showing a considerable risk and potential underuse of treatment highlight the critical need to develop strategies to improve the management and outcomes of TR patients.

Presentation and outcomes of mitral valve surgery in France in the recent era: a nationwide perspective

Objectives

Unbiased information regarding the surgical management of patients with mitral regurgitation (MR) at the nationwide level are scarce and mainly US-based. The Programme de Médicalisation des Systèmes d’Information, a mandatory national database, offers the unique opportunity to assess the presentation and outcomes of all consecutive mitral valve (MV) surgeries performed in France in the contemporary era.

Methods

We collected all MV surgeries performed for MR in France in 2014–2016. MR aetiology was classified as degenerative (DMR), secondary (SMR) or Other (rheumatic or congenital disease and infective endocarditis).

Results

During the 3-year period, 18 167 MV surgeries were performed in France (55% repair and 45% replacement; 52% isolated). Age was 66±12 years and 59% were male. Aetiology was DMR in 42%, SMR in 16% and other in 42% including 19% with uncertain aetiologies. Overall, in-hospital mortality was 6.5% and increased with age, female gender, Charlson Comorbidity Index, type of surgery (replacement vs repair), associated surgery (combined vs isolated) and MR aetiology (all p<0.01). In-hospital mortality and rate of death/readmission for heart failure (HF) at 1 year were 3.4% and 13%, respectively for DMR (2.4% and 11% for isolated DMR) and 7.8% and 27%, respectively for SMR (5.5% and 23% for isolated SMR). Repair rate was 55% overall, 68% in DMR and 72% for isolated DMR surgery (70% of all DMR). Repair rates decreased with age, Charlson Comorbidity Index and female sex (all p<0.0001).

Conclusion

In this cross-sectional contemporary prospective nationwide database, in-hospital mortality and 1 year rate of death and HF readmission were considerable overall and in all subsets. Repair rates were suboptimal overall especially in the elderly and women subsets. These results underline the need to develop strategies to improve management and outcomes of patients with both DMR and SMR.

Comparison of Early Surgical or Transcatheter Aortic Valve Replacement Versus Conservative Management in Low-Flow, Low-Gradient Aortic Stenosis Using Inverse Probability of Treatment Weighting: Results From the TOPAS Prospective Observational Cohort Study

Background

No randomized comparison of early (ie, ≤3 months) aortic valve replacement (AVR) versus conservative management or of transcatheter AVR (TAVR) versus surgical AVR has been conducted in patients with low‐flow, low‐gradient (LFLG) aortic stenosis (AS).

Methods and Results

A total of 481 consecutive patients (75±10 years; 71% men) with LFLG AS (aortic valve area ≤0.6 cm²/m² and mean gradient <40 mm Hg), 72% with classic LFLG and 28% with paradoxical LFLG, were prospectively recruited in the multicenter TOPAS (True or Pseudo Severe Aortic Stenosis) study. True‐severe AS or pseudo‐severe AS was adjudicated by flow‐independent criteria. During follow‐up (median [IQR] 36 [11–60] months), 220 patients died. Using inverse probability of treatment weighting to address the bias of nonrandom treatment assignment, early AVR (n=272) was associated with a major overall survival benefit (hazard ratio [HR], 0.34 [95% CI, 0.24–0.50]; P<0.001). This benefit was observed in patients with true‐severe AS but also with pseudo‐severe AS (HR, 0.38 [95% CI, 0.18–0.81]; P=0.01), and in classic (HR, 0.33 [95% CI, 0.22–0.49]; P<0.001) and paradoxical LFLG AS (HR, 0.42 [95% CI, 0.20–0.92]; P=0.03). Compared with conservative management in the conventional multivariate model, trans femoral TAVR was associated with the best survival (HR, 0.23 [95% CI, 0.12–0.43]; P<0.001), followed by surgical AVR (HR, 0.36 [95% CI, 0.23–0.56]; P<0.001) and alternative‐access TAVR (HR, 0.51 [95% CI, 0.31–0.82]; P=0.007). In the inverse probability of treatment weighting model, trans femoral TAVR appeared to be superior to surgical AVR (HR [95% CI] 0.28 [0.11–0.72]; P=0.008) with regard to survival.

Conclusions

In this large prospective observational study of LFLG AS, early AVR appeared to confer a major survival benefit in both classic and paradoxical LFLG AS. This benefit seems to extend to the subgroup with pseudo‐severe AS. Our findings suggest that TAVR using femoral access might be the best strategy in these patients.

Registration

URL: https://www.clinicaltrials.gov; Unique identifier: NCT01835028.

Early Midterm Results After Valve Replacement With Contemporary Pericardial Prostheses for Severe Aortic Stenosis

BACKGROUND

Clinical studies have demonstrated improved gradients after aortic valve replacement with the Trifecta (TR) valve (Abbott Cardiovascular, St Paul, MN) as compared with the Carpentier-Edwards Magna Ease (ME) valve (Edwards Lifesciences, Irvine, CA). Clinical benefits of this strategy have not been demonstrated.

METHODS

Patients undergoing aortic valve replacement for severe aortic stenosis with either valve were included. Patients were excluded if they underwent concomitant procedures other than coronary artery bypass grafting. Inverse proportion treatment weighting was used in the analysis. The primary outcome was a composite of cardiac mortality, need for reintervention, and freedom from first congestive heart failure (CHF). Secondary outcomes were all-cause mortality, the composite components, and cumulative CHF admission. Follow-up echocardiograms were assessed in a cohort of patients to assess structural valve degeneration.

RESULTS

There were 331 patients in the TR group and 360 patients in the ME group. The TR group had more women (48% vs 32%, P < .001) with smaller roots (left ventricular outflow tract diameter: TR, 2.11 cm; ME, 2.17 cm; P < .001). After weighting there was no significant difference in the composite measure between groups (P > .05). There was no difference in all-cause mortality (hazard ratio, 0.82; 95% confidence interval, 0.42-1.59; P = .56), and 5-year survival was 91.9% in the ME group and 93.4% in the TR group. There was no difference in cardiac death, reintervention, or first onset of CHF or incidence of structural valve degeneration between groups. There was no difference in the rate of admissions for CHF per 100 patients between the 2 valve types (P = .19).

CONCLUSIONS

Early hemodynamic benefits have not translated into differences in medium-term clinical outcomes between these 2 valves. Long-term follow-up is necessary.

Dismal Outcomes and High Societal Burden of Mitral Valve Regurgitation in France in the Recent Era: A Nationwide Perspective

Background Although US recent data suggest that mitral regurgitation (MR) is severely undertreated and carries a poor outcome, population-based views on outcome and management are limited. We aimed to define the current treatment standards, clinical outcomes, and costs related to MR at the nationwide level. Methods and Results In total, 107 412 patients with MR were admitted in France in 2014 to 2015. Within 1 year, 8% were operated and 92% were conservatively managed and constituted our study population (68% primary MR and 32% secondary MR). The mean age was 77±15 years; most patients presented with comorbidities. In-hospital and 1-year mortality rates were 4.1% and 14.3%, respectively. Readmissions were common (63% at least once and 37% readmitted ≥2 times). Rates of 1-year mortality or all-cause readmission and 1-year mortality or heart failure readmission were 67% and 34%, respectively, and increased with age, Charlson index, heart failure at admission, and secondary MR etiology; however, the event rate remained notably high in the primary MR subset (64% and 28%, respectively). The mean costs of hospital admissions and of readmissions were 5345±6432 and 10 080±10 847 euros, respectively. Conclusions At the nationwide level, MR was a common reason for admission and affected an elderly population with frequent comorbidities. Less than 10% of patients underwent a valve intervention. All subsets of patients who were conservatively managed incurred high mortality and readmissions rates, and MR represented a major societal burden with an extrapolated annual cost of 350 to 550 million euros (390-615 million US dollars). New strategies to improve the management and outcomes of patients with both primary and secondary MR are critical and warranted.

Presentation and management of calcific mitral valve disease

Little is known about the prevalence, presentation and management of calcific mitral valve disease (CMVD). We identified 167 patients (80 ± 10 years; 79% women) with significant CMVD undergoing transthoracic echocardiography at our institution in 2016. Patients presented with significant co-morbidities, 47% had moderate/severe mitral stenosis, 38% had 3+/4+ mitral regurgitation and 15% had a combination of both. Fifty-eight percent were symptomatic. Most symptomatic patients were managed conservatively and incurred higher mortality and mortality/heart failure admission rates than those managed surgically. These data highlight the importance of gaining mechanistic insights into CMVD to prevent its occurrence and avoid the need for high-risk surgery, which is seldom performed in contemporary practice.

EDUCATIONAL SERIES ON THE SPECIALIST VALVE CLINIC: Challenges in the diagnosis and management of valve disease: the case for the specialist valve clinic

Valvular heart disease (VHD) is responsible for a major societal and economic burden. Incidence and prevalence of VHD are high and increase as the population ages, creating the next epidemic. In Western countries, the etiology is mostly degenerative or functional disease and strikes an elderly population with multiple comorbidities. Epidemiological studies have shown that VHD is commonly underdiagnosed, leading to patients presenting late in their disease course, to an excess risk of mortality and morbidity and to a missed opportunity for intervention. Once diagnosed, VHD is often undertreated with patients unduly denied intervention, the only available curative treatment. This gap between current recommendations and clinical practice and the marked under-treatment is at least partially related to poor knowledge of current National and International Societies Guidelines. Development of a valvular heart team involving multidisciplinary valve specialists including clinicians, imaging specialists, interventional cardiologists and surgeons is expected to fill these gaps and to offer an integrated care addressing all issues of patient management from evaluation, risk-assessment, decision-making and performance of state-of-the-art surgical and transcatheter interventions. The valvular heart team will select the right treatment for the right patient, improving cost-effectiveness and ultimately patients' outcomes.

6097Aminoterminal proB-type natriuretic peptide: a key parameter to optimise therapeutic management of low-flow, low-gradient aortic stenosis

Background

B-type natriuretic peptide (BNP) and aminoterminal-proBNP (NT-proBNP) are well established surrogates of LV function impairment. However, data are scarce regarding their prognostic value to risk-stratify patients with classical low-flow, low-gradient aortic stenosis (LFLG-AS, with low left ventricular [LV] ejection fraction).

Methods

The TOPAS study is a prospective observational cohort of 240 patients with aortic valve area <0.6 cm2/m2, mean gradient<40 mmHg and LVEF<50%. True severe AS was adjudicated using flow independent grading schemes.

Results

BNP significantly predicted one-year (area under the receiver operating-characteristic curve [AUC]) 0.62±0.04, p=0.026) but not three-year mortality. After adjustment for the severity of AS, initial treatment (aortic valve replacement [AVR] vs. conservative management [ConsRx]), age, sex and the EuroSCORE (Model#1), BNP-ratio>550 pg/ml had a trend to predict time to death (HR=2.14 [1.00–4.58], p=0.05). In contrast, NT-proBNP ratio significantly predicted both one and three-year mortality (AUC=0.67±0.04 and 0.66±0.05, both p=0.001), and independently predicted time to death (HR=1.39 per 1 unit of Log transformed NT-proBNP [1.11–1.74], p=0.004). In a head-to-head comparison (108 patients with both biomarkers), the AUCs to predict one and thre-year mortality were significantly higher with NT-proBNP versus BNP (p<0.009). NT-proBNP but not BNP independently predicted mortality and significantly improved Model#1 (Likelihood ratio test Chi2=15.95, p<0.001). The category-free net reclassification index of NT-proBNP was 0.71 (p=0.008) versus 0.38 (p=0.15) for BNP. Furthermore, there was a marked survival benefit associated with AVR in patients with NT-proBNP ≥1700 pg/ml (adjusted hazard ratio (aHR) associated to AVR vs conservative management=0.52 [0.31–0.85], p=0.009), while those<1700 pg/ml had excellent one-year survival under ConsRx (only one death [4.5±4.4%] at one year as compared to 23 [37±6.2%] for ConsRx-NTproBNP>1700, aHR=0.11 [0.01–0.83], p=0.033). The survival benefit associated with AVR interacted with NT-proBNP (p<0.001) but not with true or pseudosevere AS (p=0.53 for interaction), suggesting that NT-proBNP might identify moderate AS patients but sufficiently severe valvulo-ventricular disease to justify AVR.

Survival according to NT-proBNP and AVR

Conclusion

NT-proBNP appears to be an excellent biomarker for the clinical purpose of risk-stratifying classical LFLG-AS. A threshold of 1700 pg/ml i.e. close to the diagnostic threshold for heart failure in acute dyspnea, was a strong independent determinant of the survival benefit associated with aortic valve replacement. Our findings suggest that NT-proBNP should be preferred over BNP.

Acknowledgement/Funding

Canadian Institute of Health Research

6099Impact of aortic valve replacement on outcomes of patients with low-flow, low-gradient moderate aortic stenosis

Background

Aortic valve replacement (AVR) is recommended for patients with low-flow, low-gradient (LFLG) and true-severe aortic stenosis (TSAS). However, there is very few data on the potential benefit of AVR in patients with LFLG pseudo-severe (i.e. moderate) AS (PSAS).

Methods

Consecutive patients with aortic valve area ≤0.6 cm2/m2, mean gradient <40 mmHg were prospectively recruited in a multicenter observational cohort study. The patients were categorized in TSAS vs. PSAS using previously reported thresholds of flow-independent parameters of AS severity (projected valve area at normal flow rate ≤1.0 cm2 and/or aortic valve calcium score by CT >1200 AU in women and >2000 AU in men). To account for between-treatment-group differences, inverse probability-of-treatment weighting was combined to Cox proportional hazards regression.

Results

Among the 430 patients included in this study, 297 (69%) were classified as TSAS and 274 (57%) underwent AVR. Of note, 21% of the patients treated by AVR were classified as PSAS. In patients managed conservatively (ConsRx), 52% had PSAS and 48% TSAS. During a median follow-up of 28 months [8–60], 198 patients died. The adjusted weighted hazard ratio (awHR) of death associated with AVR as compared to ConsRx was 0.42 [0.24–0.73] (p<0.0001, Figure1-Panel-A). This survival benefit associated with AVR was observed not only in patients with TSAS but also in those with PSAS (awHR: 0.29 [0.12–0.70]; p=0.006, Figure1-Panel-B).

Figure 1

Conclusion

The results of this study suggest that AVR is associated with a survival benefit not only in LFLG patients with TSAS but also in those with PSAS. Randomized trials are needed to confirm the benefit of AVR in patients with moderate AS and depressed LV systolic function.

Acknowledgement/Funding

Canadian Institute of Health Research

Repeatable and reproducible measurements of myocardial oxidative metabolism, blood flow and external efficiency using 11C-acetate PET

BACKGROUND

Non-invasive approaches to investigate myocardial efficiency can help track the progression of heart failure (HF). This study evaluates the repeatability and reproducibility of 11C-acetate positron emission tomography (PET) imaging of oxidative metabolism.

METHODS AND RESULTS

Dynamic 11C-acetate PET scans were performed at baseline and followup (47 ± 22 days apart) in 20 patients with stable HF with reduced ejection fraction. Two observers blinded to patients' clinical data used FlowQuant® to evaluate test-retest repeatability, as well as intra- and inter-observer reproducibility of 11C-acetate tracer uptake and clearance rates, for the measurement of myocardial oxygen consumption (MVO2), myocardial external efficiency (MEE), work metabolic index (WMI), and myocardial blood flow. Reproducibility and repeatability were evaluated using intra-class-correlation (ICC) and Bland-Altman coefficient-of-repeatability (CR). Test-retest correlations and repeatability were better for MEE and WMI compared to MVO2. All intra- and inter-observer correlations were excellent (ICC = 0.95-0.99) and the reproducibility values (CR = 3%-6%) were significantly lower than the test-retest repeatability values (22%-54%, P < 0.001). Repeatability was improved for all parameters using a newer PET-computed tomography (CT) scanner compared to older PET-only instrumentation.

CONCLUSION

11C-acetate PET measurements of WMI and MEE exhibited excellent test-retest repeatability and operator reproducibility. Newer PET-CT scanners may be preferred for longitudinal tracking of cardiac efficiency.

A novel echocardiographic hemodynamic index for predicting outcome of aortic stenosis patients following transcatheter aortic valve replacement

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.

Transcatheter Aortic Valve Implantation (TAVI) for Native Aortic Valve Regurgitation - A Systematic Review

BACKGROUND

Transcatheter aortic valve implantation (TAVI) has become the standard of care for management of high-risk patients with aortic stenosis. Limited data is available regarding the performance of TAVI in patients with native aortic valve regurgitation (NAVR).Methods and Results:We performed a systematic review from 2002 to 2016. The primary outcome was device success as per VARC-2 criteria. Secondary endpoints included procedural complications, and 30-day and 1-year mortality rates. A total of 175 patients were included from 31 studies. Device success was reported in 86.3% of patients - with device failure driven by moderate aortic regurgitation (AR ≥3+) and/or need for a second device. Procedural complications were rare, with no procedural deaths, myocardial infarctions or annular ruptures reported. Procedural safety was acceptable with a low 30-day incidence of stroke (1.5%). The 30-day and 1-year overall mortality rates were 9.6% and 20.0% (cardiovascular death, 3.8% and 10.1%, respectively). Patients receiving 2nd-generation valves demonstrated similar safety profiles with greater device success compared with 1st-generation valves (96.2% vs. 78.4%). This was driven by the higher incidence of second-valve implantation (23.4% vs. 1.7%) and significant paravalvular leak (8.3% vs. 0.0%).

CONCLUSIONS

TAVI demonstrates acceptable safety and efficacy in high-risk patients with severe NAVR. Second-generation valves may afford a similar safety profile with improved device success. Dedicated studies are needed to definitively establish the efficacy of TAVI in this population.

Right Heart Function During and After Community-Acquired Pneumonia in Adults

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.

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.

Right heart function deteriorates in breast cancer patients undergoing anthracycline-based chemotherapy

BACKGROUND

Cardiotoxicity from anthracycline-based chemotherapy is an important cause of early and late morbidity and mortality in breast cancer patients. Left ventricular (LV) function is assessed for patients receiving anthracycline-based chemotherapy to identify cardiotoxicity. However, animal studies suggest that right ventricular (RV) function may be a more sensitive measure to detect LV dysfunction. The purpose of this pilot study was to determine if breast cancer patients undergoing anthracycline-based chemotherapy experience RV dysfunction.

METHODS

Forty-nine breast cancer patients undergoing anthracycline-based chemotherapy at the Ottawa Hospital between November 2007 and March 2013 and who had 2 echocardiograms performed at least 3months apart were retrospectively identified. Right atrial area (RAA), right ventricular fractional area change (RV FAC) and RV longitudinal strain of the free wall (RV LSFW) were evaluated according to the American Society of Echocardiography guidelines.

RESULTS

The majority (48/49) of patients were females with an average age of 53.4 (95% CI: 50.1-56.7years). From baseline to follow-up study, average LV ejection fraction (LVEF) decreased from 62.22 (95% CI: 59.1-65.4) to 57.4% (95% CI: 54.0-60.9) (P=0.04). During the same time period, the mean RAA increased from 12.1cm(2) (95% CI: 11.1-13.0cm(2)) to 13.8cm(2) (95% CI: 12.7-14.9cm(2)) (P=0.02), mean RV FAC decreased (P=0.01) from 48.3% (95% CI: 44.8-51.74) to 42.1% (95% CI: 38.5-45.6%), and mean RV LSFW worsened from -16.2% (95% CI: -18.1 to -14.4%) to -13.81% (95% CI: -15.1 to -12.5%) (P=0.04).

CONCLUSION

This study demonstrates that breast cancer patients receiving anthracycline-based chemotherapy experience adverse effects on both right atrial size and RV function. Further studies are required to determine the impact of these adverse effects on right heart function and whether this represents an earlier marker of cardiotoxicity.

Changes in Aortic Annulus Diameter During the Cardiac Cycle and its Effect on Predicting Aortic Valve Prosthesis Size

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).

Recurrence of a Thymic Carcinoid Tumour 15 Years After Resection With Multiple Myopericardial Cardiac Metastases: The Role of Multimodality Imaging

Carcinoid tumours arising from the thymus are exceedingly rare, and cardiac metastases have not previously been described in the setting of a primary thymic carcinoid tumour. We present a patient with recurrence of a carcinoid tumour initially resected from the thymus 15 years earlier, with multiple cardiac metastases. These metastatic tumours were visualized using multiple imaging modalities, including computed tomography, transthoracic echocardiogram, magnetic resonance imaging, and octreotide scan. A subsequent biopsy confirmed recurrence of his carcinoid tumour. This case highlights the role of multimodality imaging for diagnosis and the need for continued long-term surveillance in these patients.

A Matched-Paired Comparative Analysis of the Hemodynamics of the Trifecta and Perimount Aortic Bioprostheses

BACKGROUND AND AIM OF THE STUDY

Current cohort studies comparing the Trifecta valve to alternative pericardial bioprostheses are limited by selection bias. The study aim was to determine if hemodynamics are improved after the aortic valve implantation of a Trifecta valve as compared to a standard pericardial valve, when evaluated using strict paired matching for specific key relevant confounders.

METHODS

Valve hemodynamics were compared in patients undergoing implantation with a Trifecta or Perimount valve matched for left ventricular outflow tract (LVOT) diameter, gender, age, body size, and days since surgery, using a 1:1 matched-paired cohort analysis (n = 20 per group).

RESULTS

Patients receiving a Trifecta valve had a larger increase in indexed stroke volume (SVi) relative to baseline compared to the Perimount patients (p = 0.013), in whom SVi was decreased. The mean transvalvular pressure gradient was lower in Trifecta patients despite the larger SVi (p = 0.02). The effective orifice area (EOA) and indexed EOA (EOAi) were significantly larger in Trifecta patients compared to Perimount patients (2.04 +/- 0.46 versus 1.77 +/- 0.45 cm2, p = 0.049; 1.10 +/- 0.22 versus 0.95 +/- 0.06 cm2/m2, p = 0.027, respectively), and there was a greater increase in EOA and EOAi from baseline (p = 0.010 for both). Severe prosthesis-patient mismatch (PPM) (EOAi < or = 0.65 cm2/m2) was seen in two (10%) of the Perimount cases, but in none of the patients with the Trifecta valve (p = 0.072).

CONCLUSION

Trifecta valve implantation is associated with a significant improvement in EOA and a decreased incidence of PPM as compared to the Perimount valve. The superior hemodynamic outcomes observed support consideration of this valve for aortic valve replacement, particularly in patients with a small LVOT at risk for PPM.