Low-flow, Low-gradient Research Articles

Patient survival in severe low-flow, low-gradient aortic stenosis after aortic valve replacement or conservative management.

Background and aimClassical and paradoxical low‐flow, low‐gradient (LFLG) aortic stenosis (AS) are the most challenging subtypes of AS. The current therapeutic options are aortic valve replacement (AVR) and conservative management: AVR promotes long‐term survival but is invasive, while conservative management yields a poor prognosis but is noninvasive since it uses no aortic valve replacement (noAVR). The present meta‐analysis investigated the rate of survival of patients with LFLG AS undergoing either AVR or noAVR interventions.MethodsThe meta‐analysis compared the outcomes of AVR with those of noAVR in terms of patient survival. In both groups, a meta‐regression was conducted to investigate the impact on patient survival of the left ventricular ejection fraction (LVEF), either preserved (paradoxical LFLG AS) or reduced (classical LFLG AS).ResultsThe relative risk of survival between the AVR and noAVR groups was 1.99 [1.40, 2.82] (p = .0001), suggesting that survival tends to be better in AVR patients than in noAVR patients. The meta‐regression revealed that a reduced LVEF may be related to a higher survival in AVR patients when compared to a preserved LVEF (p = .04). Finally, the analysis indicated that LVEF seems not to be prognostic of survival in noAVR patients (p = .18).ConclusionsPatients with LFLG AS have better survival if they undergo AVR. In AVR patients, reduced LVEF rather than preserved LVEF is related to better survival, whereas there seems to be no difference in prognostic value between reduced and preserved LVEF in noAVR patients.

Non-calcific aortic tissue quantified from computed tomography angiography improves diagnosis and prognostication of patients referred for transcatheter aortic valve implantation.

We aimed to investigate the role of aortic valve tissue composition from quantitative cardiac computed tomography angiography (CTA) in patients with severe aortic stenosis (AS) for the differentiation of disease subtypes and prognostication after transcatheter aortic valve implantation (TAVI). Our study included 447 consecutive AS patients from six high-volume centres reporting to a prospective nationwide registry of TAVI procedures (POL-TAVI), who underwent cardiac CTA before TAVI, and 224 matched controls with normal aortic valves. Components of aortic valve tissue were identified using semi-automated software as calcific and non-calcific. Volumes of each tissue component and composition [(tissue component volume/total tissue volume) × 100%] were quantified. Relationship of aortic valve composition with clinical outcomes post-TAVI was evaluated using Valve Academic Research Consortium (VARC)-2 definitions.High-gradient (HG) AS patients had significantly higher aortic tissue volume compared to low-flow low-gradient (LFLG)-AS (1672.7 vs. 1395.3 mm3, P < 0.001) as well as controls (509.9 mm3, P < 0.001), but increased non-calcific tissue was observed in LFLG compared to HG patients (1063.6 vs. 860.2 mm3, P < 0.001). Predictive value of aortic valve calcium score [area under the curve (AUC) 0.989, 95% confidence interval (CI): 0.981-0.996] for severe AS was improved after addition of non-calcific tissue volume (AUC 0.995, 95% CI: 0.991-0.999, P = 0.011). In the multivariable analysis of clinical and quantitative computed tomography parameters of aortic valve tissue, non-calcific tissue volume [odds ratio (OR) 5.2, 95% CI 1.8-15.4, P = 0.003] and history of stroke (OR 2.6, 95% CI 1.1-6.5, P = 0.037) were independent predictors of 30-day major adverse cardiovascular event (MACE). Quantitative CTA assessment of aortic valve tissue volume and composition can improve detection of severe AS, differentiation between HG and LFLG-AS in patients referred for TAVI as well as prediction of 30-day MACEs post-TAVI, over the current clinical standard.

Haemodynamic Patterns of Severe Aortic Stenosis

The authors present up-to-date review of clinical pathophysiology of aortic stenosis (AS) based on differentiation of its haemodynamic patterns, and some actual issues of instrumental diagnostics and classification of AS. The variety of clinical presentations of AS is based on diverse combination of pathological changes of haemodynamics. In Russian cardiology, there is no clear pathophysiological classification of AS despite of its relevance under the progress of surgical and transcatheter treatment of AS. The authors suggest the pilot haemodynamic classification of AS which includes 6 types (0-5) based on different combination of the following variables: left ventricle ejection fraction, stroke volume, mean aortic systolic pressure gradient. Severe AS with low transaortic pressure gradient in patients with depressed systolic function of the left ventricle (so called «low flow-low» gradient phenomenon) is referred to as the most frequent, classical haemodynamic pattern of low-gradient AS. The prevalence of this variant is about 10% among European population of patients with severe AS. The inconsistence between aortic valve area and mean pressure gradient is as common as in 35-40% of patients with AS, however, in 30-50% of these cases, AS is not severe. Severe AS is a surgical disease that should be treated in a surgical way in all patients but those in whom predicted risk overbalances potential benefits of the procedure. The use of integrated clinical and instrumental approach for identification of a true sever AS is the matter of great concern, as both overestimation and underestimation can misguide the clinical decision-making process. Verification of severe AS in patients with classical and paradoxical low flow-low gradient AS with specific indications for surgical treatment regarded is further emphasized in the paper. Since transcatheter aortic valve implantation has become a commonly recognized alternative to surgical aortic valve replacement, its role in the treatment of severe AS with different haemodynamic patterns is also discussed. The authors stress on the necessity of using tailored approach for treatment of AS regarding different clinical and pathophysiological scenarios: high gradient AS with preserved ejection fraction, classical and paradoxical low flow-low gradient AS.

Ejection dynamics and valve kinetics in patients with low-gradient severe aortic stenosis with preserved ejection fraction. Comparison between normal and low-flow

Abstract Background Studies of ejection dynamics in severe aortic stenosis and prosthetic valve obstruction had demonstrated a delay in aortic valve opening. Purpose The aim of this study was to compare and evaluate ejection dynamics and valve kinetics in patients with severe aortic stenosis with preserved ejection fraction with normal and low flow. Methods 83 patients (age average 68±11 years) with severe aortic stenosis (aortic valve area &amp;lt;1cm2) and preserved ejection fraction (≥50%) were studied with Doppler echocardiography and included prospectively. The ratio of aortic valve area measured at mid-deceleration and mid-acceleration (Md/Ma) were calculated using velocity of left ventricular outflow tract and aortic transvalvular velocity in continuity equation as an index of valvular kinetics. A ratio of Md/Ma &amp;gt;1 indicate delay in opening of aortic valve. Assessment of ejection dynamics was evaluated with acceleration time (AT), ejection time (ET) and the ratio AT/ET estimated from aortic Doppler velocities profiles. Aortic flow was calculated as stroke volume/ET. According to stroke volume index and mean gradient patients were classified in 3 groups: normal-flow, low-gradient (NFLG) 25 patients, low-flow, low-gradient (LFLG) 28 patients and normal-flow, high-gradient (HG) 30 patients. Analysis of the variance and coefficient of correlation “r” were used for statistical evaluation. A p value &amp;lt;0.05 was considered significant. Results There was no significant difference among the 3 groups with regard to ratio Md/Ma: NFLG 1.29±0.38, LFLG 1.22±0.26 and HG 1.23±0.45, NS. No difference was found in AT in the 3 groups, but ET was shorter in LFLG (310±30 ms) in comparison with NFLG (345±32 ms) and HG (361±31 ms), p&amp;lt;0.01. Ratio AT/ET occurred in early systole in NFLG (0.27±0.07) compared with LFLG (0.32±0.07) and HG (0.39±0.07), p&amp;lt;0.01. As expected, flow was decreased in LFLG (163±20 ml/s, p&amp;lt;0.001) compared with NFLG (217±13 ml/s) and HG (233±44 ml/s). There was no correlation among AT/ET and aortic flow or stroke volume index. Conclusions There were not differences among the groups with regard to kinetic of the valve evaluated by mean of ratio Md/Ma. According to ratio AT/ET, aortic valve takes less time to open in NFLG compared with LFLG and HG independent of aortic flow suggesting a different ejection dynamics pattern in this group. Funding Acknowledgement Type of funding source: None

Left ventricular mechanical dispersion in flow-gradient patterns of severe aortic stenosis

Abstract Purpose Patients with severe aortic stenosis are classified according to flow-gradient patterns. We investigated whether left ventricular (LV) mechanical dispersion, a marker of dyssynchrony and predictor of mortality, is associated with low-flow status in aortic stenosis. Methods and results 400 consecutive patients with QRS duration &amp;lt;120ms were included in the retrospective analysis. Patients with severe aortic stenosis (aortic valve area ≤1.0cm2) were classified as normal-flow (NF; stroke volume index &amp;gt;35ml/m2) high-gradient (HG; mean transvalvular gradient ≥40mmHg) (n=79), NF low-gradient (LG) (n=62), low-flow (LF) LG ejection fraction (EF) ≥50% (n=57), and LF LG EF&amp;lt;50% (n=23). Patients with moderate aortic stenosis (aortic valve area 1.5–1.0cm2; n=95) and patients with chronic systolic heart failure (n=84) without aortic stenosis served as comparison groups. Similar values of mechanical dispersion (calculated as standard deviation of time from Q/S onset on electrocardiogram to peak longitudinal strain in 17 left ventricular segments) was observed in patients with NF HG (49.4±14.7ms), NF LG (43.5±12.9ms), LF LG EF≥50% (47.2±16.3ms) and moderate aortic stenosis (44.2±15.7ms). Mechanical dispersion was increased in patients with LF LG EF&amp;lt;50% (60.8±20.7ms) and in chronic heart failure (59.4±16.7ms) (p&amp;lt;0.05 for both vs. NF HG‡, NF LG†, LF LG EF≥50%§ and moderate*; Figure). Mechanical dispersion correlated with LV end-systolic volume index (r=0.2530, p&amp;lt;0.0001), LVEF (r=−0.2895, p&amp;lt;0.0001) and global longitudinal strain (r=0.3108, p&amp;lt;0.0001), but not with parameters of aortic stenosis. Conclusion Mechanical dispersion was similar among flow-gradient subgroups of severe aortic stenosis with preserved LVEF, but increased in patients with low-flow low-gradient and reduced LVEF. These findings indicate that mechanical dispersion is rather a marker of systolic myocardial dysfunction than of aortic stenosis. Figure 1 Funding Acknowledgement Type of funding source: None

Use and success evaluation of percutaneous aortic balloon valvuloplasty in different hemodynamic entities of severe aortic stenosis in the TAVR era

Abstract Background In the era of transcatheter aortic valve replacement (TAVR), there is renewed interest in percutaneous balloon aortic valvuloplasty (BAV), which may qualify as the primary treatment option of choice in special clinical situations. Success of BAV is commonly defined as a significant mean pressure gradient reduction after the procedure. Purpose To evaluate the correlation of the mean pressure gradient reduction and increase in the aortic valve area (AVA) in different flow and gradient patterns of severe aortic stenosis (AS). Methods Consecutive patients from 01/2010 to 03/2018 undergoing BAV were divided into normal-flow high-gradient (NFHG), low-flow low-gradient (LFLG) and paradoxical low-flow low-gradient (pLFLG) AS. Baseline characteristics, hemodynamic and clinical information were collected and compared. Additionally, the clinical pathway of patients (BAV as a stand-alone procedure or BAV as a bridge to aortic valve replacement) was followed-up. Results One-hundred-fifty-six patients were grouped into NFHG (n=68, 43.5%), LFLG (n=68, 43.5%) and pLFLG (n=20, 12.8%) AS. Underlying reasons for BAV and not TAVR/SAVR as the primary treatment option are displayed in Figure 1. Spearman correlation revealed that the mean pressure gradient reduction had a moderate correlation with the increase in the AVA in patients with NFHG AS (r: 0.529, p&amp;lt;0.001) but showed no association in patients with LFLG (r: 0.145, p=0.239) and pLFLG (r: 0.030, p=0.889) AS. Underlying reasons for patients to undergo BAV and not TAVR/SAVR varied between groups, however cardiogenic shock or refractory heart failure (overall 46.8%) were the most common ones. After the procedure, independent of the hemodynamic AS entity, patients showed a functional improvement, represented by substantially lower NYHA class levels (p&amp;lt;0.001), lower NT-pro BNP levels (p=0.003) and a numerical but non-significant improvement in other echocardiographic parameters like the left ventricular ejection fraction (p=0.163) and tricuspid annular plane systolic excursion (TAPSE, p=0.066). An unplanned cardiac re-admission due to heart failure was necessary in 23.7% patients. Less than half of the patients (44.2%) received BAV as a bridge to TAVR/SAVR (median time to bridge 64 days). Survival was significantly increased in patients having BAV as a staged procedure (log-rank p&amp;lt;0.001). Conclusion In daily clinical practice, the mean pressure gradient reduction might be an adequate surrogate of BAV success in patients with NFHG AS but is not suitable for patients with other hemodynamic entities of AS. In those patients, TTE should be directly performed in the catheter laboratory to correctly assess the increase of the AVA. BAV as a staged procedure in selected clinical scenarios increases survival and is a considerable option in all flow states of severe AS. (NCT04053192) Figure 1 Funding Acknowledgement Type of funding source: None

Effects of patient characteristics and comorbidities on temporal trends of low-flow, low-gradient aortic stenosis phenotypes

Abstract Background Aortic stenosis (AS) is a common primary heart valve disease in the elderly. Low-flow, low-gradient (LFLG) AS is an increasingly important phenotype. Purpose To evaluate the temporal changes in incidence of severe AS phenotypes: paradoxical LFLG, classical LFLG and non-LFLG and explore risk factors that contribute to temporal trends. Methods We analyzed 25,507 consecutive transthoracic echocardiograms over 6½ years between 2013 and 2019 divided into deciles. LFLG-AS was defined as mean transvalvular pressure gradient &amp;lt;40 mmHg and stroke volume index (SVi) &amp;lt;35 mL/m2, aortic valve area (AVA) &amp;lt;1 cm2 or indexed AVA &amp;lt;0.6 cm2/m2, with either normal (paradoxical LFLG) or decreased (&amp;lt;40%; classical LFLG) left ventricular ejection fraction. Trends and associations with patients characteristics and comorbidities were assessed over time in deciles. Results Of 891 cases that fulfilled severe AS criteria, there were 536 cases of LFLG-AS (85 classical and 451 paradoxical LFLG-AS). There was a statistically significant increase in incidence of paradoxical LFLG-AS between each time interval (p&amp;lt;0.0001), while significant reduction in incidence of non-LFLG-AS (p=0.009) that was not seen with classical LFLG-AS (p=0.7) (Figure). More comprehensive echocardiographic assessment of relevant parameters over time assisted with identification of LFLG-AS cases. Intrinsic patient factors such as age and E/e' contributed towards the increasing trend of paradoxical LFLG-AS. There was a rising population aged over 70 years (p=0.01). Multivariate logistic regression analysis showed that age, sex, E/e', obesity, atrial fibrillation and heart rate were potential risk factors responsible for temporal trend towards rising paradoxical LFLG-AS incidence. There was also a gradual increase in number of patients with low transvalvular flow rate (&amp;lt;200mL/s) over time (p=0.04). Conclusion The incidence of paradoxical LFLG-AS is rising in a hospital echocardiogram service. The parallel increase in LV filling pressure and age in AS patients suggests the increment in LFLG-AS is related to changes to the LV myocardium. Subtypes of aortic stenosis over time Funding Acknowledgement Type of funding source: None

Prognostic Value of Computed Tomography–Derived Extracellular Volume in TAVR Patients With Low-Flow Low-Gradient Aortic Stenosis

ObjectivesThe association between extracellular volume (ECV) measured by computed tomography angiography (CTA) and clinical outcomes was evaluated in low-flow low-gradient (LFLG) aortic stenosis (AS) patients undergoing transcatheter aortic valve replacement (TAVR). BackgroundPatients with LFLG AS comprise a high-risk group with respect to clinical outcomes. Although ECV, a marker of myocardial fibrosis, is traditionally measured with cardiac magnetic resonance, it can also be measured using cardiac CTA. The authors hypothesized that in LFLG AS, increased ECV may be associated with adverse clinical outcomes. MethodsIn 150 LFLG patients with AS who underwent TAVR, ECV was quantified using pre-TAVR CTA. Echocardiographic and clinical information including all-cause death and heart failure rehospitalization (HFH) was obtained from electronic medical records. A Cox proportional hazards model was used to evaluate the association between ECV and death+HFH. ResultsDuring a median follow-up of 13.9 months (range 0.07 to 28.9 months), there were 31 death+HFH events (21%). Patients who experienced death+HFH had a greater median Society of Thoracic Surgery score (9.9 vs. 4.7; p < 0.01), lower left ventricular ejection fraction (42.3 ± 20.2% vs. 52.7 ± 17.2%; p < 0.01), lower mean transvalvular gradient (24.9 ± 8.9 mm Hg vs. 28.1 ± 7.3 mm Hg; p = 0.04) and increased mean ECV (35.5 ± 9.6% vs. 29.9 ± 8.2%; p < 0.01) compared with patients who did not experience death+HFH. In a multivariable Cox proportional hazards model, increase in ECV was associated with increase in death+HFH, (hazard ratio per 1% increase: 1.04, 95% confidence interval: 1.01 to 1.09; p < 0.01). ConclusionsIn patients with LFLG AS, CTA measured increase in ECV is associated with increased risk of adverse clinical outcomes post-TAVR and may thus serve as a useful noninvasive marker for prognostication.

Risk of mortality following transcatheter aortic valve replacement for low-flow low-gradient aortic stenosis.

Low-flow low-gradient (LF-LG) aortic stenosis (AS) is associated with high mortality, even after transcatheter aortic valve replacement (TAVR). Further knowledge of risk indicators is needed and a clinical risk score would be desirable for optimizing patient selection and therapeutic strategy. The study cohort comprised of 219 consecutive LF-LG AS patients undergoing TAVR from 2008 to 2018 in two high-volume German centers. Predictive factors for one-year all-cause mortality were defined according to a Cox proportional hazard model. At one-year follow-up after TAVR, 28% of patients had died. A multivariate model revealed six independent predictors of one-year mortality: history of myocardial infarction (HR 2.05, 95%CI 1.13-3.72), eGFR < 30ml/min/1.73m2 (HR 2.75, 95%CI 1.48-5.11), tricuspid regurgitation moderate or more (HR 2.06, 95%CI 1.14-3.72), stroke volume index < 25mL/m2 (HR 2.03, 95%CI 1.14-3.62), self-expandable device (HR 2.72, 95%CI 1.17-6.27), and non-transfemoral approach (HR 3.42, 95%CI 1.28-9.14). The Rhineland Risk Score (RRS) consisting of these variables (c statistic 0.75, 95%CI 0.68-0.82, p < 0.001) was superior to the EuroSCORE II (c statistic 0.63) and STS-PROM score (c statistic 0.69) at predicting one-year mortality. Patients with a RRS ≥ 8 had a prohibitive risk of one-year mortality of 67.6% (95%CI 52.0-82.4%). In patients with LF-LG AS, history of myocardial infarction, renal dysfunction, tricuspid regurgitation, a low stroke volume index, self-expandable device, and non-femoral approach were associated with increased 1-year mortality after TAVR. The RRS might serve as a helpful tool for risk prediction and patient selection for TAVR in patients with LF-LG AS.

Comparison of the results in Normal Flow High Gradient and Low Flow Low Gradient patients after correction of pronounced aortic stenosis with Ozaki procedure in the long-term observation

Relevance.It has been proven that patients with Low Flow Low Gradient (LFLG) after aortic valve replacement with biological or mechanical prostheses have a higher mortality rate and the number of adverse events compared with patients with Normal Flow High Gradient (NFHG). However, there are currently no comparative studies of patients with NFHG and LFLG after the Ozaki procedure. The better hemodynamic properties of autopericardial cusps compared with biological prostheses can more favorably influence the results in patients with LFLG in the short and long-term follow-up periods.&#x0D; Aim.1. Compare the hospit and long-term results of patients of the LFLG group with the results of patients of the NFHG group after the Ozaki procedure. 2. Identify predictors of hospital and long-term mortality in patients with LFLG.&#x0D; Materials and methods.All patients have been divided into two groups. Group 1: 137 patients with NFHG and signs of classic aortic stenosis: AVA1 cm2, Gmean40, SV index 35 ml/m2and normal left ventricle (LV) ejection fraction. Group 2. 71 patients with LFLG and underestimation of the average gradient indices (Gmean40) despite a decrease in the aortic valve aperture AVA1 cm2amid a decrease in the index of stroke volume 35 ml/m2and LV systolic function.&#x0D; Results.Hospital mortality after surgical correction of AV stenosis was significantly higher in patients of group 2: 3 (4.2%) patients and 1 (0.7%) patients, respectively (p=0.002). Survival at the maximum follow-up period for patients with LFLG was significantly lower than in the group of patients with NFHG 88.6 (95% confidence interval CI 4449.6) and 97.8 (95% CI 48.951), respectively (p=0.009). According to the results of the Cox regression analysis, the independent predictors of mortality in the long-term follow-up of patients with LFLG are the SV odds ratio 0.8 (95% CI 0.91.1);p=0.008 and the global longitudinal LV deformation (GLS) odds ratio 0.56 (95% CI 0.471.1);p=0.01.&#x0D; Conclusions.1. After the Ozaki procedure, patients with the LFLG group have higher risks of adverse events, both at the hospital stage and in the long-term follow-up, compared to patients with NFHG. 2. The duration of ischemia and LV mass are predictors of hospital mortality in the LFLG group of patients. 3. Predictors of long-term mortality in patients with LFLG are LV stroke volume index and global longitudinal LV deformation.

Clinical application of stress echocardiography in valvular heart disease: an expert consensus of the Working Group on Valvular Heart Disease of the Polish Cardiac Society.

Valvular heart diseases (VHDs) constitute an increasing problem both as a consequence of population aging and as the sequelae of other heart diseases. Accurate diagnosis is essential for correct clinical decision‑making; however, in many patients, transthoracic and transesophageal echocardiography is insufficient. Stress echocardiography (SE) proved to be a useful tool allowing for simultaneous assessment of left ventricular contractile reserve and HVD hemodynamics under conditions of physiological or pharmacological stress. It is recommended for assessing the severity of VHD, guiding the choice of treatment, as well as for surgical risk stratification. It can be applied both in asymptomatic patients with severe VHD and in symptomatic individuals with moderate disease. In patients with VHD, SE can be performed either as exercise stress echocardiography (ESE) or dobutamine stress echocardiography (DSE). The first modality is recommended to unmask symptoms or abnormal blood pressure response in patients with aortic stenosis (AS) who report to be asymptomatic or in those with mitral stenosis with discordance between clinical symptoms and the severity of valve disease on transthoracic echocardiography. In asymptomatic patients with paradoxical low‑flow, low‑gradient (LFLG) AS, ESE can be used to assess the severity of stenosis. On the other hand, low‑dose DSE can be a useful diagnostic tool in classical LFLG AS, providing information on stenosis severity and contractile reserve. Moreover, SE is indicated in patients with prosthetic valve when there is discordance between symptoms and echocardiographic findings. It is also recommended in high‑risk surgical patients with VHD with poor functional capacity and more than 2 clinical risk factors. The present paper discusses in detail the use of SE in VHD.

High-molecular-weight von Willebrand Factor multimer ratio differentiates true-severe from pseudo-severe classical low-flow, low-gradient aortic stenosis.

Upon high wall shear stress, high-molecular-weight (HMW) von Willebrand Factor (VWF) multimers are degraded, thus, HMW VWF multimer deficiency mirrors haemodynamics at the site of aortic stenosis (AS). The aim of the present study was to analyse the role of HMW VWF multimer ratio for subcategorization of classical low-flow, low-gradient (LF/LG) AS. Eighty-three patients with classical LF/LG AS were prospectively recruited and HMW VWF multimer pattern was analysed using a densitometric quantification of western blot bands. Patients were subclassified into true-severe (TS) and pseudo-severe (PS) classical LF/LG AS based on dobutamine stress echocardiography (DSE). Positive and negative predictive values (PPV/NPV) of HMW VWF multimer ratio for diagnosis of the TS subtype were calculated. HMW VWF multimer ratio in TS classical LF/LG AS was significantly decreased compared to PS classical LF/LG AS (0.86 ± 0.27 vs. 1.06 ± 0.09, P < 0.001). HMW VWF multimer deficiency occurred exclusively in the TS subtype with an optimal PPV of 1.000 and NPV of 0.379. HMW VWF multimer ratio showed a strong correlation with mean transvalvular pressure gradients during DSE (r = -0.616; P < 0.001). HMW VWF multimer ratio measured at baseline was higher compared to levels measured after DSE (0.87 ± 0.27 vs. 0.84 ± 0.31; P = 0.031) indicating DSE-induced increased proteolysis. HMW VWF multimer ratio represents a valuable biomarker for classical LF/LG AS subclassification and mirrors haemodynamics during DSE. HMW VWF multimer ratio identifies the TS subtype without the use of other imaging techniques.

Contemporary use of balloon aortic valvuloplasty and evaluation of its success in different hemodynamic entities of severe aortic valve stenosis.

To evaluate outcome assessment of percutaneous balloon aortic valvuloplasty (BAV) in different flow and gradient patterns of severe aortic stenosis (AS). The mean pressure gradient reduction after BAV is an often-used surrogate parameter to evaluate procedural success. The definition of a successful BAV has not been evaluated in different subgroups of severe AS, which were introduced in the latest guidelines on the management of patients with valvular heart disease. In this observational study, consecutive patients from July 2009 to March 2018 undergoing BAV were divided into normal-flow high-gradient (NFHG), low-flow low-gradient (LFLG), and paradoxical low-flow low-gradient (pLFLG) AS. Baseline characteristics, hemodynamic, and clinical information were collected and compared. One-hundred-fifty-six patients were grouped into NFHG (n = 68, 43.5%), LFLG (n = 68, 43.5%), and pLFLG (n = 20, 12.8%) AS. Mean age of the study population was 81 years. Cardiogenic shock or refractory heart failure (46.8%) was the most common underlying reasons for BAV. Spearman correlation revealed that the mean pressure gradient reduction, determined by echocardiography, had a moderate correlation with the increase in the aortic valve area (AVA) in patients with NFHG AS (ρ: 0.529, p < .001) but showed no association in patients with LFLG (ρ: 0.017, p = .289) and pLFLG (ρ: 0.030, p = .889) AS. BAV as bridge to surgical or transcatheter aortic valve replacement was possible in 44.2% of patients, with no difference between groups (p = .070). The mean pressure gradient reduction might be an adequate surrogate parameter for BAV success in patients with NFHG AS but is not suitable for patients with other hemodynamic entities.

Characteristics and usefulness of unintended premature ventricular contraction during invasive assessment of aortic stenosis

BackgroundPostextrasystolic potentiation (PESP)-associated augmentation in left ventricular-aorta pressure gradient (LVAoG) observed after incidental premature ventricular contraction (PVC) during resting echocardiography is similar to dobutamine stress echocardiography (DSE)-associated augmentation in LVAoG in patients with low-flow, low-gradient (LF-LG) aortic stenosis (AS). What is not known is whether a similar relationship exists when unintended PVC causes PESP during cardiac catheterization in patients with AS. MethodsWe retrospectively reviewed all catheterizations performed for patients with at least moderate AS who had LVAoG assessment. Univariate and multivariate analyses were conducted to determine the predictors of pre- and post-PVC mean LVAoG ≥ 40 mmHg. ResultsBetween September 2015 to September 2017, of 140 individuals undergoing cardiac catheterization, 34 met study criteria. Mean pre-PVC gradient was 38.9 ± 22.8 mmHg. All patients exhibited PESP-associated augmentation of LVAoG by an average of 28 ± 12%. In multivariate analysis, the only significant predictor of post-PVC mean LVAoG ≥ 40 mmHg was preserved LV function (OR 6.81; 95% CI 1.41–32.82, p = 0.02). Inability to generate ≥ 40 mmHg of mean LVAoG post-PVC had 100% specificity for nonsevere AS in our observational cohort. ConclusionsUnintended but interpretable PVCs occurred in one in four patients with AS undergoing cardiac catheterization with measurable hemodynamics. All of our patients with PVCs, regardless of underlying LVEF, exhibited PESP-associated augmentation of LVAoG. Our exploratory analysis suggests that inability to generate ≥40 mmHg of mean LVAoG post-PVC is highly specific for nonsevere AS.

CRT-600.20 Transcatheter Aortic Valve Replacement Outcomes in Patients With Low-Gradient Severe Aortic Stenosis: A Systematic Review and Meta-Analysis

Transcatheter aortic valve replacement (TAVR) has gained popularity due to its safety and feasibility in severe aortic stenosis (AS). There are limited outcomes data for TAVR performed in low-flow, low-gradient (LFLG) severe AS. Systemic review of literature identified 9 studies (n=24327; mean age

Left ventricular mechanical dispersion in flow-gradient patterns of severe aortic stenosis with narrow QRS complex

Patients with severe aortic stenosis are classified according to flow-gradient patterns. We investigated whether left ventricular (LV) mechanical dispersion, a marker of dyssynchrony and predictor of mortality, is associated with low-flow status in aortic stenosis. 316 consecutive patients with aortic stenosis and QRS duration < 120 ms were included in the retrospective analysis. Patients with severe aortic stenosis (aortic valve area ≤ 1.0 cm2) were classified as normal-flow (NF; stroke volume index > 35 ml/m2) high-gradient (HG; mean transvalvular gradient ≥ 40 mmHg) (n = 79), NF low-gradient (LG) (n = 62), low-flow (LF) LG ejection fraction (EF) ≥ 50% (n = 57), and LF LG EF < 50% (n = 23). Patients with moderate aortic stenosis (aortic valve area 1.5–1.0 cm2; n = 95) served as comparison group. Mechanical dispersion (calculated as standard deviation of time from Q/S onset on electrocardiogram to peak longitudinal strain in 17 left ventricular segments) was similar in patients with NF HG (49.4 ± 14.7 ms), NF LG (43.5 ± 12.9 ms), LF LG EF ≥ 50% (47.2 ± 16.3 ms) and moderate aortic stenosis (44.2 ± 15.7 ms). In patients with LF LG EF < 50%, mechanical dispersion was increased (60.8 ± 20.7 ms, p < 0.05 vs. NF HG, NF LG, LF LG EF ≥ 50% and moderate AS). Mechanical dispersion correlated with global longitudinal strain (r = 0.1354, p = 0.0160) and heart rate (r = 0.1587, p = 0.0047), but not with parameters of aortic stenosis. Mechanical dispersion was similar among flow-gradient subgroups of severe aortic stenosis with preserved LVEF, but increased in patients with low-flow low-gradient and reduced LVEF. These findings indicate that mechanical dispersion is rather a marker of systolic myocardial dysfunction than of aortic stenosis.

P1537 Myocardial work in patients with aortic stenosis before and short term after transcatheter aortic valve replacement

Abstract Objective The newly introduced noninvasive myocardial work analysis could potentially be beneficial in predicting the best timing for aortic valve replacement as well as clinical outcomes in patients with high grade aortic valve stenosis (AS), which is the leading valvular disease in the modern aging society. However, to date there is little data on the applicability of the method in the setting of extremely increased left ventricular (LV) afterload. Purpose In this pilot study, we aimed to apply myocardial work analysis in patients with increased LV afterload due to severe AS and to investigate the differences of myocardial work parameters in patients with different AS entities. In addition, we analyzed the early changes of myocardial work after the afterload reduction by transcatheter aortic valve replacement (TAVR). Methods We retrospectively studied echocardiographic data of 28 consecutive patients with severe AS before and 7 days after TAVR. Global Work Index (GWI), Global Constructive Work (GCW), Global Wasted Work (GWW) and Global Work Efficiency (GWE) were calculated using commercially available software based on noninvasive pressure-strain loops. In order to correct for underestimation of intraventricular pressure, we added the mean aortic valve pressure gradient to the peripheral systolic blood pressure used by the software. Results From the included patients (mean age 76 ± 10 years) 13 were classified as having normal flow (NF) severe AS, 8 had low flow low gradient (LFLG) and 7 paradoxical low flow low gradient (PLFLG) AS. GWI and GCW were significantly lower in patients with LFLG AS compared to patients with NF or PLFLG AS (936 ± 528 mmHg% vs. 2493 ± 485 mmHg% vs. 1959 ± 469 mmHg% [p &amp;lt; 0.005] and 1132 ± 477 mmHg% vs. 2770 ± 507 mmHg% vs. 2189 ± 603 mmHg%, [p &amp;lt; 0.005], respectively). 7 days after TAVR, GCW and GWI decreased significantly in patients with NF AS. In other AS entities, a trend towards increased GWI and GCW was observed, but the difference did not reach statistical significance. GWI and GCW remained significantly lower in LFLG AS group when compared to NF and PLFLG groups (1069 ± 378 mmHg% vs. 1919 ± 310 mmHg% vs. 2064 ± 842 mmHg% [p &amp;lt; 0.005] and 1286 ± 346 mmHg% vs. 2107 ± 258 mmHg% vs. 2227 ± 949 mmHg% [p &amp;lt; 0.005]) early after TAVR. GWE and GWW did not differ between the groups and were not influenced by TAVR. Conclusion In this pilot study we applied the adapted myocardial work analysis in patients with increased afterload due to severe AS. We have shown that GCW and GWI are significantly higher in patients with NF AS when compared to LFLG and PLFLG AS. The differences between the groups persisted early after TAVR in spite of significant reduction of GWI and GWC in patients with NF AS. The clinical and prognostic importance of these findings are still to be investigated in a bigger cohort study.

P300 Reappraisal of aortic stenosis severity grading inconsistencies using 3D aortic valve area

Abstract Funding Acknowledgements no fundings Background Different 3D imaging modalities have been proposed to overcome the limitations in aortic stenosis (AS) grading derived from underestimation of left ventricular outflow tract (LVOT) area by 2D transthoracic echocardiography (2D-TTE). Transesophageal echocardiography manual and software measurements (3D-TEEm and 3D-TEEs) and multidetector computed tomography (MDCT) have been recently been shown as valuable tools for AS grading using a combined approach incorporating 3D LVOT measurements and 2D Doppler parameters in the continuity equation (CE). This approach results particularly useful in cases of 2D-TTE grading inconsistence. As all these 3D imaging modalities provide larger AVA compared to 2D-TTE, we have recently proposed a 1.2 cm2 AVA cut-off could to define AS severity with 3D-TEE and MDCT. Purpose To compare AVA measurements with 3D-TEEm and 3D-TEEs using MDCT as gold standard in order to assess inconsistencies and evaluate the impact of a 1.2 cm2 AVA cut-off on AS severity grading. Methods 288 patients (80 ± 11 years, 52.4% male) with symptomatic AS underwent 2D-TTE, 3D-TTEm, 3D-TEEs and MDCT within the same hospitalization. 3D-TEE LVOT reconstruction was performed manually and with semi-automated software (EchoPAC version 201). 3D-TEEm, 3D-TEEs and MDCT LVOT areas were combined with 2D-TTE Doppler parameters to calculate AVA by CE. The grading of AS was reassessed in patients with low flow-low gradient AS using a 1.2 cm2 cut-off for severity. Results Patients were classified according to flow state (stroke volume index ≥35 ml/m2 or &amp;lt;35 ml/m2) and mean pressure gradient (MPG ≥40 mmHg or &amp;lt;40 mmHg) into 4 groups: normal flow-high gradient (NF-HG; n 173, 60%), normal flow-low gradient (NF-LG; n 45, 15.5%), low flow-high gradient (LF-HG; n 39, 13.5%), and low flow-low gradient (LF-LG; n 31, 11%) AS. Among patients classified as LF-LG AS, 95%, 55%, 29% and 55% of cases were classified as severe by 2D-TTE, 3D-TEEm, 3D-TEEs and MDCT respectively using a 1.0 cm2 AVA cut-off. When the proposed severity AVA cut-off of 1.2 cm2 was applied using 3D imaging modalities, the proportion of severe AS significantly increased to 84% (p = 0.012) (3D-TEEm), 52% (p = 0.046) (3D-TEEs) and 71% (p &amp;lt; 0.001) (MDCT) respectively. Conclusion The use of a 1.2 cm2 AVA cut-off for 3D-TEE and MDCT significantly reduces the number of cases of inconsistently graded AS, increasing the proportion of patients with severe AS.

P660 Arterial hypertension as confounding factor in the echocardiographic assessment of patients with significant aortic stenosis

Abstract Purpose Increased arterial pressure affects the accuracy of clinical conclusions in a number of cardiac pathologies, including valvulopathies. We investigated the influence of increased blood pressure in the assessment of multiple echo variables in patients with significant aortic stenosis of different physiologies. Methods Seventy two patients (33 women, aged 72 ± 12 years old, EF: 56 ± 9%) with significant aortic stenosis [18 (25%) with low flow low gradient (LFLG) and 7 (10%) with paradoxic LFLG (PLFLG) physiology] and arterial systolic pressure ≥140 mmHg on admission, were assessed with a full 2D and Doppler echocardiographic study including non-invasive assessment of pressure recovery and valvuloarterial impedance (z). Echo study was performed on two occasions during their hospitalization, on admission and after normalization of blood pressure. Arterial pressure was controlled by any therapeutic means at the discretion of the referring physician. Significant serial changes between echo variables were assessed by the Student paired t-test. Results Arterial pressure and heart rate were significantly lowered between the two studies (from 152 ± 13 to 116 ± 11 mmHg and 78 ± 7 to 73 ± 5, p&amp;lt; 0,001 respectively). Differences between the echo variables are depicted in the following table. Conclusions Small but significant changes were noticed in several echo parameters after lowering blood pressure in patients with significant aortic stenosis. These patients should always be assessed after normalization of their blood pressure since the degree of stenosis can be erroneously overestimated and affect clinical decision. p &amp;lt; 0,001 Echo variable 1st study 2nd study Stroke vol index (i) (ml/m2) 37,1 ± 9,5 44,1 ± 10* Mean gradient (mmHg) 42 ± 6,2 44 ± 5,8 * Pressure recovery (mmHg) 8,4 ± 2,5 9,5 ± 2,7* Z (mmHg/mL * m2) 5,4 ± 1,5 3,8 ± 1,1* AVAi (cm2/m2) 0,44 ± 0,06 0,49 ± 0,06*

624 Is TAVI a useful procedure in paradoxical low flow-low gradient aortic stenosis? A long-term mortality study

Abstract Background Clinical outcomes of patients with paradoxical low-flow, low-gradient aortic stenosis (PLF-LG) undergoing valve replacement are controversial. PLF-LG is a combination of a small aortic valve area (AVA &amp;lt; 1cm²), a preserved left ventricular (LV) ejection fraction (LVEF≥50%), and a ‘paradoxical’ low mean gradient due to the presence of low LV stroke volume (≤35 mL/m²). The low flow state is explained by the presence of a high afterload and pronounced LV concentric remodeling, with impaired LV filling. Surgical aortic valve replacement has been associated with very positive outcomes in normal-flow high-gradient (NF-HG) AS, whereas poorer outcomes has been reported in patients with PLF-LG AS. Purpose The aim of this study is to determine the clinical outcomes in patients with PLF-LG AS undergoing transcatheter aortic valve implantation (TAVI) compare to NF-HG patients. Methods A total of 624 patients (age 81 ± 7 years) with symptomatic severe AS and preserved LVEF who underwent TAVI, was enrolled and divided in 2 groups: group NF-HG included 554 patients (89%) and group PLF-LG including 70 patients (11%). At 1-year follow-up, death and clinical events were reported. Results TAVI was feasible in all patients. A significant reduction in mean aortic pressure gradient was observed after TAVI both in PLF-LG (baseline, 30 ± 6 mmHg; 1-year, 12 ± 4 mmHg; p &amp;lt; 0.001) and in NF-HG (baseline, 55 ± 12 mmHg; 1-year, 11 ± 4 mmHg; p &amp;lt; 0.001) together with an increase in AVA (PLF-LG: baseline, 0.73 ± 0.16 cm², 1-year: 1.82 ± 0.43 cm², p &amp;lt; 0.001; NF-HG: baseline, 0.66 ± 0.18 cm², 1-year: 1.84 ± 0.38cm², p &amp;lt; 0.001). Perioperative mortality at 30-days was similar in group NF-HG (17/554, 3%) and in group PLF-LG (2/70, 3%). Figure shows the survival curves up to 5 years follow-up according to the two groups. PLF-LG and HG-AS had similar survival rate throughout the long-term follow-up. Similarly, rehospitalization rate was not different in the two groups (PLF-LG: 12% vs NF-HG: 7%, p = 0.127). Conclusions Differently from surgical series, TAVI in PLF-LG AS is a useful procedure showing similar mortality and rehospitalization rates compared to NF-HG AS patients. Abstract 624 Figure. Survival curve