Dobutamine Stress Echocardiography in Low-Gradient Aortic Stenosis.

IMPORTANCE: Guidelines recommend the use of dobutamine stress echocardiography (DSE) in patients with low-gradient aortic stenosis (AS) and left ventricular ejection fraction (LVEF) <50%. However, a paucity of DSE data exists when LVEF >35%. OBJECTIVE: To examine the diagnostic accuracy of DSE in patients with low-gradient AS with a wide range of LVEF and to examine the interaction between the diagnostic accuracy of DSE and LVEF. DESIGN, SETTING, AND PARTICIPANTS: Patients with mean gradient <40 mm Hg, aortic valve area <1.0 cm2, and stroke volume index ≤35 mL/m2 undergoing DSE and cardiac computer tomography (C-CT) were identified from 3 prospectively collected patient cohorts and stratified according to LVEF: LVEF<35%, LVEF 35% to 50%, and LVEF>50%. EXPOSURE: Dobutamine stress echocardiography and C-CT were performed on patients with low-gradient AS. MAIN OUTCOMES AND MEASURES: Severe AS was defined as aortic valve calcification score ≥2,000 arbitrary units (AU) among men and ≥1,200 AU for women on C-CT. RESULTS: Of 221 patients included in the study, 78 (35%) presented with LVEF <35%, 67 (30%) with LVEF 35% to 50%, and 76 (34%) with LVEF >50%. Mean-gradient and aortic valve peak velocity during DSE showed significant diagnostic heterogeneity between LVEF groups, being most precise when LVEF <35% (both areas under the curve [AUC] = 0.90), albeit with optimal thresholds of 30 mm Hg and 377 cm/sec and a limited diagnostic yield in patients with LVEF ≥35% (AUC = 0.67 and 0.66 in LVEF 35% to 50% and AUC = 0.65 and 0.60 in LVEF ≥50%). Using guideline thresholds led to a sensitivity/specificity of 49%/84% for all patients with LVEF <50%. CONCLUSION AND RELEVANCE: While DSE is safe and leads to an increase in stroke volume in patients with low-gradient AS regardless of LVEF, the association between DSE gradients and AS severity assessed by C-CT demonstrates important heterogeneity depending on LVEF, with the highest accuracy in patients with LVEF <35%.

Effect of Sex and Flow Status on Outcomes After Surgical or Transcatheter Aortic Valve Replacement.

Background: Low stroke volume index <35 ml/m2 despite preserved ejection fraction (paradoxical low flow [PLF]) is associated with adverse outcomes in patients with aortic stenosis undergoing transcatheter aortic valve replacement (TAVR) or surgical aortic valve replacement (SAVR). However, whether the risk associated with PLF is similar in both sexes is unknown. Objectives: The purpose of this study was to analyze the risk associated with PLF in severe aortic stenosis for men and women randomized to TAVR or SAVR. Methods: Patients with ejection fraction ≥50% from the PARTNER (Placement of Aortic Transcatheter Valves) 2 and 3 trials were stratified by sex and treatment arm. The impact of PLF on the 2-year occurrence of the composite of death or heart failure hospitalization (primary endpoint) and of all-cause mortality alone (secondary endpoint) was analyzed. Analysis of variance was used to assess baseline differences between groups. Multivariate Cox regression analysis was used to identify predictors of the endpoint. Results: Out of 2,242 patients, PLF was present in 390 men and 239 women (30% vs 26%, P = 0.06). PLF was associated with a higher rate of NYHA functional class III to IV dyspnea (60% vs 54%, P < 0.001) and a higher prevalence of atrial fibrillation (39% vs 24%, P < 0.001). PLF was a significant predictor of the primary endpoint among women undergoing SAVR in multivariate analysis (adjusted HR: 2.25 [95% CI: 1.14-4.43], P = 0.02) but was not associated with a worse outcome in any of the other groups (all P > 0.05). Conclusions: In women with PLF, TAVR may improve outcomes compared to SAVR. PLF appears to have less impact on outcomes in men.

Prevalence, Characteristics, and Impact on Prognosis of Aortic Stenosis in Patients With Cardiac Amyloidosis.

BACKGROUND: Cardiac amyloidosis (CA) is frequently found in older patients with aortic stenosis (AS). However, the prevalence of AS among patients with CA is unknown. The objective was to study the prevalence and prognostic impact of AS among patients with CA. METHODS AND RESULTS: We conducted a retrospective analysis of a prospective registry comprising 976 patients with native aortic valves who were confirmed with wild type transthyretin amyloid (ATTRwt), hereditary variant transthyretin amyloid (ATTRv), or immunoglobulin light-chain (AL) CA. CA patients' echocardiograms were re-analyzed focusing on the aortic valve. Multivariable Cox regression analysis was performed to assess the mortality risk associated with moderate or greater AS in ATTRwt CA. The crude prevalence of AS among patients with CA was 26% in ATTRwt, 8% in ATTRv, and 5% in AL. Compared with population-based controls, all types of CA had higher age- and sex-standardized rate ratios (SRRs) of having any degree of AS (AL: SRR, 2.62; 95% Confidence Interval (CI) [1.09-3.64]; ATTRv: SRR, 3.41; 95%CI [1.64-4.60]; ATTRwt: SRR, 10.8; 95%CI [5.25-14.53]). Compared with hospital controls, only ATTRwt had a higher SRR of having any degree of AS (AL: SRR, 0.97, 95%CI [0.56-1.14]; ATTRv: SRR, 1.27; 95%CI [0.85-1.44]; ATTRwt: SRR, 4.01; 95%CI [2.71-4.54]). Among patients with ATTRwt, moderate or greater AS was not associated with increased all-cause death after multivariable adjustment (hazard ratio, 0.71; 95%CI [0.42-1.19]; P=0.19). CONCLUSIONS: Among patients with CA, ATTRwt but not ATTRv or AL is associated with a higher prevalence of patients with AS compared with hospital controls without CA, even after adjusting for age and sex. In our population, having moderate or greater AS was not associated with a worse outcome in patients with ATTRwt.

Low body mass index and risk of mortality after mitral transcatheter edge-to-edge repair procedure: The "obesity paradox".

BACKGROUND: Most patients undergoing the mitral transcatheter edge-to-edge repair (TEER) technique are elderly comorbid patients. Low body mass index (BMI) < 23 kg/m2 has been identified in other elderly populations as a risk factor, but has not been studied sufficiently in mitral TEER. AIMS: We aimed to study the impact of low BMI (23 kg/m2) on the outcome after mitral TEER. METHODS: Patients undergoing first-time TEER for mitral regurgitation at a single tertiary center were included, with the exclusion of patients with preprocedural hemodynamic instability or missing BMI. The primary endpoint was all-cause mortality. Secondary endpoints were long-term major bleeding or admission with heart failure. RESULTS: A total of 120 patients (mean age 76 ± 10 years, 76% men) were included in the study. Thirty-nine (31%) had low BMI. Patients with low BMI had a similar symptomatic benefit as patients with BMI ≥ 23 kg/m2 at 1 year regarding decrease in diuretics dose and decrease in New York Heart Association (NYHA) class (p > 0.05). In a multivariable Cox regression analysis, BMI as a continuous variable (hazard ratio [HR]: 0.93 [95% confidence interval, CI: 0.87-0.99], p = 0.03) and low BMI (HR: 1.99 [95% CI: 1.12-3.52], p = 0.02) were associated with the primary outcome. Low BMI was not significantly associated with major bleeding (subdistribution hazard ratio [SHR]: 2.39 [95% CI: 0.96-5.97], p = 0.06) or admission with heart failure (SHR: 1.06 [95% CI: 0.61-1.88], p = 0.83) during follow-up with univariable competing risk regression analysis. CONCLUSION: Low BMI is a risk factor for mortality after mitral valve TEER, confirming the presence of an "obesity paradox" in this population and should receive attention in patient selection.

Association Between Vegetation Size and Outcome in the Partial Oral Antibiotic Endocarditis Treatment Trial.

Step-down oral antibiotic therapy is associated with a non-inferior long-term outcome compared with continued intravenous antibiotic therapy in the treatment of left-sided infective endocarditis. We aimed to analyze whether step-down oral therapy compared with continued intravenous antibiotic therapy is also associated with a non-inferior outcome in patients with large vegetations (vegetation length ≥ 10 mm) or among patients who underwent surgery before step-down oral therapy. We included patients without presence of aortic root abscess at diagnosis from the POET (Partial Oral Antibiotic Endocarditis Treatment) study. Multivariable Cox regression analyses were used to find associations between large vegetation, cardiac surgery, step-down oral therapy, and the primary end point (composite of all-cause mortality, unplanned cardiac surgery, embolic event, or relapse of positive blood cultures during follow-up). A total of 368 patients (age 68 ± 12, 77% men) were included. Patients with large vegetations (n = 124) were more likely to undergo surgery compared with patients with small vegetations (n = 244) (65% vs 20%, p <0.001). During a median 1,406 days of follow-up, 146 patients reached the primary end point. Large vegetations were not associated with the primary end point (hazard ratio 0.74, 95% confidence interval 0.47 to 1.18, p = 0.21). Step-down oral therapy was non-inferior to continued intravenous antibiotic in all subgroups when stratified by the presence of a large vegetation at baseline and early cardiac surgery. Step-down oral therapy is safe in the presence of a large vegetation at diagnosis and among patients who underwent early cardiac surgery.

Angiotensin II Receptor Blockers Are Associated With Reduced Valvular Fibrosis in Women With Aortic Stenosis.

BACKGROUND: Angiotensin receptor blockers (ARBs) may slow down the progression of aortic stenosis (AS) through their antifibrotic effect. Women present more valvular fibrosis than men, so ARBs may have more effect in females. Our aim was to assess the impact of ARBs on the remodelling of the aortic valve in men and women. METHODS: We included patients who had an aortic valve replacement with or without coronary bypass grafting from 2006 to 2013. Patients with missing echocardiographic or histologic data were excluded. Warren-Yong and fibrosis scores of the explanted valves were performed. Patients were divided into 4 phenotypes according to their Warren-Yong and fibrosis scores: mild calcification/fibrosis, severe calcification/fibrosis group, predominant fibrosis group, predominant calcification group. RESULTS: Among the 1321 included patients, the vast majority (89%) has severe AS. Patients in the predominant fibrosis group, compared with the predominant calcium group, were more often female (39% vs 31%; P = 0.008) with bicuspid valves (44% vs 34%; P = 0.002), and less often used ARBs (25% vs 30%; P = 0.046). Female sex was independently associated with being in the predominant fibrosis group (odds ratio 1.45, 95% confidence interval 1.08-1.95; P = 0.01), with a significant interaction between female sex and ARBs. Women taking ARBs compared with women not taking ARBs had significantly lower fibrosis scores (P < 0.001). This difference was not seen in men. CONCLUSIONS: In this large series of patients with moderate-severe AS, among the women there was a negative association between intake of ARBs and valvular fibrosis. Thus, the possible effects of ARBs may be sex specific, with a larger therapeutic role in women.

Pressure-flow responses to exercise in aortic stenosis, mitral regurgitation and diastolic dysfunction.

BACKGROUND: Haemodynamic exercise testing is important for evaluating patients with dyspnoea on exertion and preserved ejection fraction. Despite very different pathologies, patients with pressure (aortic stenosis (AS)) and volume (mitral regurgitation (MR)) overload and diastolic dysfunction after recent acute myocardial infarction (AMI) reach similar filling pressure levels with exercise. The pressure-flow relationships (the association between change in cardiac output (∆CO) and change in pulmonary arterial wedge pressure (∆PAWP) may provide insight into haemodynamic adaptation to exercise in these groups. METHODS AND RESULTS: One hundred sixty-eight subjects aged >50 years with a left ventricular ejection fraction of ≥50% underwent invasive exercise testing. They were enrolled in four different studies: AS (40 patients), AMI (52 patients), MR (43 patients) and 33 healthy subjects. Haemodynamic data were measured at rest, at 25 W, 75 W and at peak exercise. In all groups, PAWP increased with exercise. The greatest increase was observed in patients with AMI (from 12.7±3.9 mm Hg to 33.1±8.2 mm Hg, p<0.0001) and patients with AS (from 11.8±3.9 mm Hg to 31.4±6.1 mm Hg, p<0.0001), and the smallest was observed in healthy subjects (from 8.3±2.4 mm Hg to 21.1±7.5 mm Hg, p<0.0001). In all groups, the relative pressure increase was greatest at the beginning of the exercise. CO increased most in healthy patients (from 5.3±1.1 to 16.0±3.0 L/min, p<0.0001) and least in patients with AS (from 5.3±1.2 L/min to 12.4±2.6 L/min, p<0.0001). The pressure-flow relationships (∆PAWP/∆CO) and differed among groups (p=0.02). In all groups, the pressure-flow relationship was steepest in the initial phase of the exercise test. The AMI and AS groups (2.3±1.2 mm Hg/L/min and 3.0±1.3 mm Hg/L/min, AMI and AS, respectively) had the largest overall pressure-flow relationship; the healthy group had the smallest initially and at peak exercise (1.3±1.1 mm Hg/L/min) followed by MR group (1.9±1.4 mm Hg/L/min). CONCLUSION: The pressure-flow relationship was steepest in the initial phase of the exercise test in all groups. The pressure-flow relationship differs between groups. TRIAL REGISTRATION NUMBERS: NCT01974557, NCT01046838, NCT02961647 and NCT02395107.

Hemodynamic changes during aortic valve surgery among patients with aortic stenosis.

Introduction. Patients with severe aortic stenosis (AS) undergoing surgery are at increased risk of hypotension and hypoperfusion. Although treatable with inotropic agents or fluid, little is known about how these therapies affect central hemodynamics in AS patients under general anesthesia. We measured changes in central hemodynamics after dobutamine infusion and fluid bolus among patients with severe AS and associated these changes with preoperative echocardiography. Methods. We included 33 patients with severe AS undergoing surgical AVR. After induction of general anesthesia, hemodynamic measurements were obtained with a pulmonary artery catheter, including Cardiac index (CI), stroke volume index (SVi) and pulmonary capillary wedge pressure (PCWP). Measurements were repeated during dobutamine infusion, after fluid bolus and lastly after sternotomy. Results. General anesthesia resulted in a decrease in CI and SVi compared to preoperative values. During dobutamine infusion CI increased but mean SVi did not (38 ± 12 vs 37 ± 13 ml/m2, p = .90). Higher EF and SVi before surgery and a larger decrease in SVi after induction of general anesthesia were associated with an increase in SVi during dobutamine infusion. After fluid bolus both CI, SVi (48 ± 12 vs 37 ± 13 ml/min/m2, p < .0001) and PCWP increased. PCWP increased mostly among patients with a larger LA volume index. Conclusion. In patients with AS, CI can be increased with both dobutamine and fluid during surgery. Dobutamine's effect on SVI was highly variable and associated with baseline LVEF, and an increase in CI was mostly driven by an increase in heart rate. Fluid increased SVi at the cost of an increase in PCWP.

Assessment of diastolic function in aortic stenosis: A comparison between 2009 and 2016 guidelines.

AIMS: New diastolic dysfunction (DD) guidelines were introduced in 2016 to replace the 2009 guidelines, but have not yet been evaluated in aortic stenosis (AS). We aimed to compare the 2009 and 2016 DD guidelines in severe AS patients in terms of association with left ventricular (LV) and left atrial (LA) remodeling, with pulmonary capillary wedge pressure (PCWP) at rest and exercise, and with prognosis. METHODS AND RESULTS: We included 212 patients with severe AS (112 undergoing AVR, 100 asymptomatic). Echocardiography, magnetic resonance imaging, and brain natriuretic peptides (BNP) were performed/measured. Thirty-nine asymptomatic patients had PCWP measured during rest and maximal exertion. Asymptomatic patients were followed for 3.1 years for the combined endpoint of death, AVR or admission with heart failure. The 2009 and 2016 DD guidelines agreed poorly with each other (Cohens' κ = .15). 2009 guidelines showed many ambiguous DD findings. With the 2016 guidelines, 20% of patients had indeterminate DD. DD grade 2 according to 2016 guidelines showed stronger association with symptom status, BNP, global longitudinal strain (GLS) and peak exercise PCWP than 2009 guidelines. For indeterminate DD patients according to 2009 guidelines, GLS above the median was associated with event-free survival (HR .11 (95% CI .02-.53)). For neither guideline was DD associated with the combined endpoint in asymptomatic patients. CONCLUSION: The 2016 guidelines show a stronger association with BNP, GLS, and exercise PCWP than the 2009 guidelines. The 2016 guidelines result in 20% of patients with indeterminate DD; however, these patients may possibly be stratified according to GLS.

[Takotsubo cardiomyopathy as a result of refeeding syndrome in a patient with anorexia nervosa].

A 39-year-old woman with severe anorexia nervosa, complicated with a low ejection fraction of 10-20%, developed refeeding syndrome, massive oedema, and acute cardiac failure, but recovered during specialised nutritive treatment and inotropic medication with levosimendan. With this case report, we aim to draw attention to the refeeding syndrome and to the cardiological consequences of anorexia nervosa. Takotsubo cardiomyopathy is reversible if the proper treatment is given.

First-phase ejection fraction: association with remodelling and outcome in aortic valve stenosis.

BACKGROUND: First-phase ejection fraction (EF1), the left ventricular (LV) ejection fraction (EF) until the time of peak transaortic velocity, is a novel marker of subclinical LV dysfunction able to predict adverse events in aortic stenosis (AS). This study investigated the association between end-systolic wall stress (ESWS) and EF1 in severe AS, as well as the prognostic value of EF1 in severe asymptomatic AS. METHODS: Two prospectively gathered cohorts of 94 asymptomatic patients and 108 symptomatic patients scheduled for aortic valve replacement (AVR), all with severe AS (aortic valve area <1 cm2) were stratified according to the median value of EF1 (33%). EF1 was defined as the EF at peak transaortic velocity. Asymptomatic patients were followed up for 3 years for the combined end-point of death, AVR or admission with heart failure. RESULTS: EF1 correlated with EF and was inversely associated with ESWS. In multivariate regression analysis, ESWS (p<0.001) and replacement fibrosis measured by MRI (p=0.02) were associated with EF1. Among asymptomatic patients, EF1 above the median was associated with the combined primary endpoint (HR=0.53 (95% CI 0.33 to 0.87)), while global longitudinal strain and EF were not. Among 42 patients with discordant AS (mean gradient <40 mm Hg), EF1 above median was associated with the primary endpoint (HR 0.28 (95% CI 0.12 to 0.61)). CONCLUSION: EF1 is an afterload-dependent measure that is associated with events in patients with asymptomatic severe AS. The afterload dependency of EF1 may be useful in timing of risk stratification in patients with discordant AS. TRIAL REGISTRATION NUMBERS: NCT02395107 and NCT02316587.

The association between aortic valve calcification, cardiovascular risk factors, and cardiac size and function in a general population.

To determine the presence and extent of aortic valve calcification (AVC) quantified by non-contrast cardiac computed tomography (NCCT), to determine the association between traditional cardiovascular risk factors and AVC score, and to evaluate the association between AVC and cardiac size and function assessed by echocardiography, in a general population aged 65-75 years. A random sample of 2060 individuals were invited to undergo NCCT through which their AVC score was assessed. Individuals with an AVC score ≥ 300 arbitrary units (AU) were invited for a transthoracic echocardiography together with age-matched controls. Descriptive statistics and multiple regression analyses were performed to identify risk factors associated with AVC and to describe associations between AVC score and echocardiographic findings. Of 2060 individuals invited 664 males and 636 females participated. Among those, 455 (68.5%) of males and 358 (56.3%) of females had AVC scores > 0 AU. The median AVC score was 6 AU (IQR 0-3064). Seventy-seven (11.6%) males and 20 (3.1%) females had an AVC score ≥ 300 AU. In a multiple regression analysis, age, sex, prior cardiovascular disease, smoking, and hypertension were associated with AVC score, while diabetes, hypercholesterolemia and kidney function were not. Individuals with AVC ≥ 300 AU had higher peak and mean aortic valve gradient, smaller indexed aortic valve area, greater left ventricular mass, and larger left atrial (LA) volume. In a random population sample of individuals aged 65-75 years, AVC was common and associated with most known cardiovascular risk factors. AVC ≥ 300 AU was associated with concentric remodeling and LA dilatation.

Sex differences in aortic valve calcification in severe aortic valve stenosis: association between computer tomography assessed calcification and valvular calcium concentrations.

AIMS: The aims of this study were to investigate the correlation and sex differences between total valve calcium, valve calcium concentration, and aortic valve calcification (AVC) in explanted valves from patients with severe aortic valve stenosis undergoing aortic valve replacement (AVR). METHODS AND RESULTS: Sixty-nine patients with severe aortic stenosis (AS) scheduled for elective AVR underwent echocardiography and cardiac computed tomography (CT) prior to surgery (AVCin vivo) and CT of the explanted aortic valve (AVCex vivo). Explanted valves were prepared in acid solution, sonicated, and analysed with Arsenazo III dye to estimate total valve calcium and valve calcium concentration. Median AVCex vivo was 2082 (1421-2973) AU; mean valve calcium concentration was 1.43 ± 0.42 µmol Ca2+/mg tissue; median total valve calcium 156 (111-255) mg Ca2+, and valve calcium density 52 (35-81) mg/cm2. AVC displayed a strong correlation with total valve calcium (R2 = 0.98, P < 0.001) and a moderate correlation with valve calcium concentration (R2 = 0.62, P < 0.001). Valvular calcium concentration was associated with sex, aortic valve area, and mean gradient. After adjusting for age and estimated glomerular filtration rate, sex and mean gradient remained associated with valve calcium concentrations. CONCLUSION: AVC score provides a strong estimate for total valve calcium but to a lesser degree calcium concentration in the valve tissue of patients with severe AS. Females presented lower valvular calcium concentrations than males irrespective of AS severity, adding evidence and providing support to the important point that sex differences in valvular calcium concentration in AS does not reflect valvular size.

Extent of arterial calcification by conventional vitamin K antagonist treatment.

BACKGROUND AND AIMS: Vitamin K antagonists (VKA) remain the most frequently prescribed oral anticoagulants worldwide despite the introduction of non-vitamin K antagonist oral anticoagulants (NOAC). VKA interfere with the regeneration of Vitamin K1 and K2, essential to the activation of coagulation factors and activation of matrix-Gla protein, a strong inhibitor of arterial calcifications. This study aimed to clarify whether VKA treatment was associated with the extent of coronary artery calcification (CAC) in a population with no prior cardiovascular disease (CVD). METHODS: We collected data on cardiovascular risk factors and CAC scores from cardiac CT scans performed as part of clinical examinations (n = 9,672) or research studies (n = 14,166) in the period 2007-2017. Data on use of anticoagulation were obtained from the Danish National Health Service Prescription Database. The association between duration of anticoagulation and categorized CAC score (0, 1-99, 100-399, ≥400) was investigated by ordered logistic regression adjusting for covariates. RESULTS: The final study population consisted of 17,254 participants with no prior CVD, of whom 1,748 and 1,144 had been treated with VKA or NOAC, respectively. A longer duration of VKA treatment was associated with higher CAC categories. For each year of VKA treatment, the odds of being in a higher CAC category increased (odds ratio (OR) = 1.032, 95%CI 1.009-1.057). In contrast, NOAC treatment duration was not associated with CAC category (OR = 1.002, 95%CI 0.935-1.074). There was no significant interaction between VKA treatment duration and age on CAC category. CONCLUSIONS: Adjusted for cardiovascular risk factors, VKA treatment-contrary to NOAC-was associated to higher CAC category.

Aortic Stenosis: What Risks Do the Stresses of Noncardiac Surgery or Pregnancy Pose and How Should They Be Managed?

Studies suggest that patients with aortic stenosis have increased risk in pregnancy and delivery and during anesthesia and surgery, although there are significant degrees of uncertainty as to the exact risks and best way to manage such patients. This article reviews current literature regarding impact of aortic stenosis on pregnancy and anesthesia during noncardiac surgery. There are shortcomings in the scientific evidence. Most of the available studies are observational and often retrospective and therefore there is a great deal of bias. This leads to difficulty in drawing conclusions in terms of how to apply the published information to clinical management.

Association between left ventricular diastolic function and right ventricular function and morphology in asymptomatic aortic stenosis.

BACKGROUND: Aortic stenosis (AS) is a progressive disease in which left ventricular (LV) diastolic dysfunction is common. However, the association between diastolic dysfunction and right ventricular (RV) loading conditions and function has not been investigated in asymptomatic AS patients. METHODS AND FINDINGS: A total of 41 patients underwent right heart catheterization and simultaneous echocardiography at rest and during maximal supine exercise, stratified according to resting diastolic function. Cardiac chamber size and morphology was assessed using cardiac magnetic resonance imaging (cMRI). RV stroke work index, pulmonary artery (PA) compliance, PA elastance, PA pulsatility index, and right atrial pressure (RAP) were calculated at rest and maximal exercise. Ten patients (24%) had normal LV filling pattern, 20 patients (49%) had grade 1, and 11 patients (27%) had grade 2 diastolic dysfunction. Compared to patients with normal diastolic filling pattern, patients with diastolic dysfunction had lower RV end-diastolic volume (66 ± 11 ml/m2 vs. 79 ± 15 ml/m2, p = 0.02) and end-systolic volume (25 ± 7 ml/m2 vs. 32 ± 9 ml/m2, p = 0.04). An increase in mean RAP to ≥15 mmHg following exercise was not seen in patients with normal LV filling, compared to 4 patients (20%) with mild and 7 patients (63%) with moderate diastolic dysfunction (p = 0.003). PA pressure and PA elastance was increased in grade 2 diastolic dysfunction and correlated with RV volume and maximal oxygen consumption (r = -0.71, p < 0.001). CONCLUSIONS: Moderate diastolic dysfunction is associated with increased RV afterload (elastance), which is compensated at rest, but is associated with increased RAP and inversely related to maximal oxygen consumption during maximal exercise.

End-systolic wall stress in aortic stenosis: comparing symptomatic and asymptomatic patients.

Aims: In aortic stenosis (AS), there is poor association between symptoms and conventional markers of AS severity or left ventricular (LV) systolic function. This may reflect that symptoms arise from LV diastolic dysfunction or that aortic valve area (AVA) and transvalvular gradient do not reflect afterload. We aimed to study the impact of afterload (end-systolic wall stress [ESWS]) on the presence of symptoms in AS and to test whether symptoms are related to increased ESWS or LV remodelling. Methods and results: In a prospective study, ESWS was estimated by measuring LV wall thickness from MRI and estimated LV end systolic pressure from echocardiographic mean gradient and systolic blood pressure in 78 patients with severe AS scheduled for aortic valve replacement and 91 patients with asymptomatic severe AS. Symptomatic patients had lower indexed AVA (0.40±0.11 vs 0.45±0.09 cm2/m2, p=0.009). They had undergone more extensive remodelling (MRI LV mass index [LVMi]: 85±24 vs 69±17 g/m2, p<0.0001), had higher tricuspid regurgitant gradient (24±8 mm Hg vs 19 ± 7 mm Hg, p=0.0001) and poorer global longitudinal strain (-15.6±3.8 vs -19.9±3.2%, p<0.0001). ESWS was higher among symptomatic patients (96±51 vs 76±25 kdynes/cm2, p=0.003). Multivariate logistic regression identified echocardiographic relative wall thickness, tricuspid gradient, mitral deceleration time, early diastolic strain rate, MRI LVMi, MRI LV end-diastolic volume index and ESWS as independently associated with being symptomatic. Conclusion: ESWS can be estimated from multimodality imaging combining MRI and echocardiography. It is correlated with LV remodelling and neurohormonal activation and is independently associated with symptomatic status in AS.

Postoperative atrial fibrillation after aortic valve replacement is a risk factor for long-term atrial fibrillation.

OBJECTIVES: Postoperative atrial fibrillation (POAF) is a common complication following cardiac surgery. However, knowledge on the rate of long-term atrial fibrillation (LTAF) after POAF remains unclear. We investigated predictors of POAF in patients with aortic stenosis undergoing surgical aortic valve replacement, and assessed the rate of LTAF during follow-up. METHODS: We prospectively included 96 adult patients with severe aortic stenosis undergoing surgical aortic valve replacement. Patients with previous atrial fibrillation (AF) were excluded. Patients underwent echocardiography, cardiac computed tomography and magnetic resonance imaging immediately prior to surgery. Surgical aortic clamp time and postoperative C-reactive protein (CRP) were documented. POAF was defined as AF recorded within 7 days of surgery. Through chart review, patients were followed up for documented episodes of LTAF occurring more than 7 days after surgery. RESULTS: POAF occurred in 51 patients (53%). It was associated with larger preoperative echocardiographic left atrial volume index (44 ± 12 vs 37 ± 8 ml/m2, P = 0.004), longer aortic clamp time [80 (70-102) vs 72 (62-65) min, P = 0.04] and higher CRP on first postoperative day [80 (64-87) vs 65 (44-83) mg/l, P = 0.001]. Multivariable logistic regression revealed that left atrial volume index [odds ratio (OR) 1.07, 95% confidence interval (CI) 1.02-1.13; P = 0.005] and postoperative CRP (OR 1.03, 95% CI 1.01-1.05; P = 0.006) were the only independent predictors of POAF. During 695 days (25th-75th percentile: 498-859 days) of follow-up, LTAF occurred in 11 patients of whom 10 were in the POAF group (hazard ratio 9.4, 95% CI 1.2-74; P = 0.03). CONCLUSIONS: POAF is predicted by left atrial volume index and postoperative CRP. Patients with POAF have a 9-fold increase risk of developing symptomatic LTAF during follow-up. CLINICAL TRIAL REGISTRATION NUMBER: ClinicalTrials.gov (NCT02316587).