Diagnostic value and prognostic impact of various invasively derived hemodynamic parameters in patients with severe aortic stenosis undergoing TAVI

Background

Ejection time (ET) and Acceleration time (AT) have been described as echocardiographic markers for aortic stenosis (AS).1 Moreover, in a recent study time between invasively measured left ventricular and aortic systolic pressure peaks (T-LVAo) was associated with anatomic AS severity.2 However, the diagnostic value of these parameters has not been validated in a larger patient cohort and their prognostic impact in AS patients undergoing transcatheter aortic valve implantation (TAVI) remains unknown.

Purpose

We aimed to assess the diagnostic value and prognostic impact of ET, AT, and T-LVAo as assessed by invasive measurements in patients undergoing TAVI for severe AS.

Methods

This retrospective single-centre analysis studied 1478 patients undergoing TAVI from 2014 to 2019 for severe AS. All patients received echocardiographic, multislice computed tomography (MSCT) and invasive hemodynamic evaluation with simultaneous pressure measurements in left ventricle and aorta prior to TAVI. Anatomic AS severity was assessed according to MSCT-derived aortic valve calcification density (AVCd) defined as calcium volume per annulus area. All hemodynamic parameters were calculated offline using a dedicated software.

Results

Median patients' age was 81.2 (76.8–84.7) years and 807 (54.6%) were women. Predicted operative risk for mortality was 3.8 (2.6–5.7)% according to STS Score. Medians of invasively derived parameters were 70.0 ms (46.0–98.0) for T-LVAo, 308.0 ms (276.0–336.0) for ET, 180.0 ms (146.0–206.0) for AT. In spline analysis correlation of T-LVAo (Spearman: r=0.35; p<0.001) and ET (Spearman: r=0.18; p<0.001) with AVCd was significant but weak. AT showed negligible correlation with ACVd (Spearman: r=−0.05; p=0.089). The optimal cutoff for death (CD) according to C-statistic was 274 ms for ET and 158 ms for AT. Patients with ET or AT ≥ CD showed lower short and mid-term mortality rates compared to patients with ET or AT < CD (ET ≥ vs. < CD: mortality at 1-year: 14.5 vs. 31.9%, 3-years: 28.3 vs. 53.5%, all p<0.001; AT ≥ vs < CD: mortality at 1-year: 15.5 vs. 25.9%, p<0.001, 3-years: 34.0 vs. 41.0%, p=0.0032). Moreover, multivariate analysis for mortality identified ET (HR 0.58 [95% CI 0.43–0.77; p<0.001]) and AT (HR 0.65 [95% CI 0.49–0.86; p=0.0027]) to be associated with beneficial outcome after TAVI, independent from clinical risk factors and echocardiography-derived parameters like LVEF, mean gradient or stroke volume index. In contrast, T-LVAo showed no prognostic impact according to uni- or multivariate analyses.

Conclusion

T-LVAo provides the highest diagnostic value among the investigational hemodynamic parameters, however correlation with AVCd was weak. ET and AT are strong independent outcome predictors beyond clinical risk factors and standard echocardiographic parameters in AS patients following TAVI. Accordingly, use of ET and AT might improve risk assessment in patients scheduled for TAVI.

Funding Acknowledgement

Type of funding sources: None.

Prevalence and prognostic impact of left ventricular outflow tract calcification in patients with severe aortic stenosis undergoing transfemoral TAVI using second-generation devices

Introduction

Left ventricular outflow tract (LVOT) calcification is known to be associated with adverse outcomes after TAVI in patients receiving first-generation transcatheter heart valves (THV). Second-generation THV have been shown to improve outcomes of TAVI patients. Thus, aim of this study is to assess the prevalence of LVOT calcification as well as its impact on procedural and clinical outcomes in patients with severe aortic stenosis undergoing transfemoral TAVI with second-generation THV in a real-world patient cohort.

Methods

In this retrospective single-center analysis patients receiving transfemoral TAVI with second-generation THV for the treatment of aortic stenosis (AS) between 05/2012 and 06/2018 and with adequate CT data were included (n=836). Amount of LVOT calcification was measured quantitatively from contrast-enhanced multislice CT using a dedicated software. Baseline characteristics and outcomes were compared according to presence of significant LVOT calcification (none/≤10 mm3 vs. >10 mm3). Procedural and clinical outcome were assessed in accordance with VARC-2 criteria. All-cause mortality was assessed by Kaplan-Meier method, median follow-up was 1.4 years.

Results

Significant LVOT calcification was present in 37.0% of patients. Patients with LVOT calcification were older (all results as follows without (w/o) vs. with (w) LVOT calcification: 81.4 (77.1, 84.8) vs. 82.3 (78.0, 86.3) years, p=0.006), but presented similar STS scores compared to those without LVOT calcification (5.4±4.7 vs. 5.4±3.5%, p=0.94). Moreover, patients with LVOT calcification had higher mean transvalvular gradients at baseline (30.0 (21.0, 41.0) vs. 37.0 (25.7, 47.0) mmHg, p<0.001) and higher aortic valve calcium volume (380.7 (226.8, 632.1) vs. 663.6 (364.5, 1070.3) mm3, p<0.001). There were no significant differences in rate of device success (97.0 vs. 94.2%, p=0.11), renal failure (2.6 vs. 2.3%, p=1.00), myocardial infarction (0.9 vs. 1.2%, p=1.00) or rate of permanent pacemaker implantation at 30 days after TAVI (16.6 vs. 17.2%, p=0.91). However, rate of TIA/stroke was significantly higher in patients with LVOT calcification (2.1 vs. 6.2%, p=0.0098). Furthermore, patients with LVOT calcification had a higher rate of more than mild paravalvular leakage at discharge (3.8 vs. 7.6%, p=0.033). Rate of 1 year all-cause mortality (17.8 vs. 21.2%, p=0.23) was not significantly different between both groups.

Conclusions

Significant LVOT calcification is present in a substantial proportion of patients receiving TAVI. In such patients, higher rates of cerebrovascular events and more than mild PVL occurred compared to those without significant LVOT calcification even with currently available second-generation THV. Although these findings did not translate into higher mortality rates in the present study, they underline the need for further optimization of THV technology in order to improve outcomes among all TAVI patients.

Figure 1. 1-year mortality

Funding Acknowledgement

Type of funding source: None

P4576Prognostic value of high-sensitivity troponin I measured by two assays in patients presenting with suspected myocardial infarction

Background

Troponin is the gold-standard biomarker for diagnosing acute myocardial infarction (AMI). High-sensitivity assayed troponin has furthermore proven to be a promising biomarker for the prediction of future adverse cardiovascular events.

Objective

Aim of the current study was to assess and compare the prognostic value of a single troponin I measurement in patients with suspected AMI analysed by a novel high-sensitive Troponin I (hs-TnI) assay, promising detection of very low troponin I plasma levels, as well as by a well-established hs-TnI assay.

Methods

Data was derived from two prospective studies of patients presenting with suspected AMI to the emergency department. Hs-TnI was measured in a total of 2,312 patients using both a novel hs-TnI assay (1; Singulex Clarity cTnI) and a widely applied and approved hs-TnI assay (2; Abbott Diagnostics, ARCHITECT i1000SR). The prognostic impact for overall mortality of both hs-TnI assays was assessed in the total patient cohort as well as in the subgroups of patients with AMI (n=498) and without AMI (n=1,813). Kaplan-Meier analyses stratified by hs-TnI tertiles in each subgroup were performed. Moreover, prognostic impacts of both hs-TnI assays were analysed in a multiple adjusted cox regression model. We compared the performance of both hs-TnI assays in predicting adverse outcome using c-statistics. Median follow up time was 2.4 years.

Results

Patients with AMI presented with significantly higher hs-TnI values on admission. Unadjusted Kaplan-Meier analysis survival curves in the entire study population (Figure 1) as well as in the non-AMI subgroup indicated a significantly higher event-rate in the third tertiles of both hs-TnI assays for overall mortality. In contrast, irrespective of the used assay we found no association between troponin I plasma levels and overall mortality in the AMI group. Cox regression models revealed significant associations between hs-TnI and overall mortality in the entire study cohort (1: HR 1.17 [1.10–1.25], p<0.001; 2: HR 1.18 [1.11–1.26], p<0.001) and in the non-AMI subgroup (1: HR 1.39 [1.21–1.6], p<0.001; 2: 1.49 [1.28–1.74], p<0.001), but no significant association in the AMI subgroup (1: HR 1.02 [0.91–1.13], p=0.79; 2: 1.03 [0.93–1.3], p=0.55). The addition of hs-TnI to cardiovascular risk factors for the prediction of overall mortality led to a similar increment in the c-index by both hs-TnI assays of 0.014; p=0.034 (1) and 0.015; p=0.037 (2), respectively.

Figure 1. Overall mortality

Conclusion

Hs-TnI assayed on admission is an independent predictor of adverse outcome beyond conventional risk factors in patients presenting to the emergency department with suspected but ruled-out diagnosis of AMI. In patients with the established diagnosis of AMI hs-TnI is not predictive for adverse outcome. Our findings demonstrate the potential role of hs-TnI as a biomarker for risk prediction. Both assessed hs-TnI assays performed equally in predicting adverse events.

P3858High H2FPEF score is an independent predictor of adverse outcome in patients with severe aortic stenosis and preserved ejection fraction undergoing TAVR

Background

Recently, the H2FPEF score has been developed in an evidence-based approach relying on simple clinical and echocardiographic variables. It enables the identification of patients with high probability of prevalent heart failure with preserved ejection fraction (HFpEF) which is associated with a dismal prognosis. Left ventricular diastolic dysfunction, a key mechanism in HFpEF, is also a common finding in patients with severe aortic stenosis.

Objective

To assess the prognostic impact of the H2FPEF score in patients with preserved ejection fraction and severe aortic stenosis undergoing Transcatheter Aortic Valve Replacement (TAVR).

Methods

Among 1148 patients with preserved ejection fraction who received TAVR at our institution between 2013 and 2018, data for calculation of the H2FPEF score was available in 535 patients. Score variables include BMI >30 kg/m2, arterial hypertension, atrial fibrillation, pulmonary hypertension >35 mmHg, age >60 years, and elevated LV filling pressure. Patients were dichotomized according to “low” (1–5 points; n=377) and “high” H2FPEF scores (6–9; n=158). Kaplan-Meier survival curves and Cox regression analyses were used to assess the prognostic impact of H2FPEF scores. Median follow-up time was 0.3 years.

Results

TAVR patients presenting with high H2FPEF scores had higher prevalence of moderate to severe mitral regurgitation (19.4% vs. 33.6%, p<0.001) as well as tricuspid regurgitation (15.2% vs. 35.1%, p<0.001), and presented with lower stroke volume index (42.2 ml/m2 vs. 36.0 ml/m2, p<0.001) compared to those with low H2FPEF scores. All-cause mortality one year after TAVR was significantly higher in patients in the high H2FPEF score group (10.5% vs. 21.0%, p=0.0019, Figure 1). Multivariate analysis revealed a high H2FPEF score to be independently predictive for 1-year all-cause mortality (HR 2.66, 95% CI: 1.41–5.02, p=0.025). Among the single H2FPEF score variables, atrial fibrillation (HR 3.45, 95% CI: 1.86–6.40, p<0.001) and systolic pulmonary hypertension >55 mmHg (HR=2.68, 95% CI: 0.97–7.40, p=0.057) were strong independent predictors of adverse outcome.

Figure 1. All-cause mortality of patients undergoing TAVR after one year stratified by low (1–5 points) and high (6–9) H2FPEF score

Conclusion

An elevated H2FPEF score of >6 is independently predictive for mortality in patients with preserved ejection fraction undergoing TAVR for severe aortic stenosis. Our findings provide evidence that the H2FPEF score, which was meant for diagnostic use originally, is able to serve as a prognostic tool in patients with preserved ejection fraction undergoing TAVR, highlighting the adverse impact of diastolic dysfunction in patients with preserved ejection fraction and aortic stenosis.

P1848Prevalence and outcomes in patients with Heyde syndrome after transcatheter aortic valve implantation, a single centre experience

Introduction

Heyde syndrome is known as the association of severe aortic stenosis (AS) and recurrent gastrointestinal bleeding (GIB) from angiodysplasia. To date only few data exist regarding the prevalence of Heyde syndrome and results after transcatheter aortic valve implantation (TAVI) for the treatment of AS.

Purpose

We sought to evaluate the prevalence of Heyde syndrome in a routine clinical cohort of patients undergoing TAVI and analyze the effectiveness of treatment of AS regarding recurrent GIB in these patients.

Methods

We conducted a retrospective single-center analysis of 2545 consecutive patients who underwent TAVI for the treatment of AS in 2008–2017. Patients with a history of GIB were identified. The diagnosis of Heyde syndrome was defined as a clinical triad of presence of severe AS, a history of recurrent GIB, and an endoscopic diagnosis of angiodysplasia. GIB of unknown origin or related to other causes was defined as bleeding unrelated to angiodysplasia. Clinical outcomes of patients with Heyde syndrome were evaluated with emphasis on bleeding complications and recurrence of GIB.

Results

A history of GIB prior to TAVI was detected in 190 patients (7.5%) of the TAVI cohort. Among them, 143 patients had a GIB unrelated to angiodysplasia (5.6%) and 47 patients (1.8%) were diagnosed with Heyde syndrome. Median age and STS-PROM were 80.7 (75.3, 84.0) years and 4.7 (2.7, 9.0) respectively in Heyde patients. TAVI was successfully performed in all cases (66% endovascular access, 34% transapical access). The effective orifice areas increased from 0.8±0.1 cm2 to 2.1±0.5 cm2. Periprocedural major/life-threatening bleeding was found in 6 patients (12.8%), mainly access-related and none due to GIB. In 51% of Heyde-patients transfusion of 4.5±5.7 packed red blood cells was required during the index hospitalisation. During a mean follow-up of 12 months, recurrent GIB after TAVI was detected in 32% of patients with Heyde syndrome. In contrast only 18% of patients with GIB unrelated to angiodysplasia (Non-Heyde) had recurrent GIB after TAVI. In patients diagnosed with Heyde syndrome and recurrent GIB after TAVI the rate of residual mild or moderate paravalvular regurgitation was higher compared to those with an unremarkable course (73% vs. 37%, p=0.045).

Figure 1. 1-year Follow-Up

Conclusions

A relevant number of patients presenting for treatment of AS can be diagnosed with Heyde syndrome. In these patients TAVI can be successfully performed with moderate incidence of periprocedural bleeding complications but significant transfusion rates. Regardless of successful treatment of AS, recurrent GIB was detected in a significant number of Heyde patients during follow-up. The possible association with residual paravalvular regurgitation requires further investigation to improve treatment options in patients with Heyde syndrome.