Intraoperative finding of immobile leaflet(s) following freshly implanted bioprosthetic valves: clinical characteristics and impact on outcomes

Funding Acknowledgements

Type of funding sources: None.

BACKGROUND

Detection of immobile leaflets immediately following bioprosthetic valve implantation is a rare but important intraoperative finding. Restriction of leaflet movement can occur in the closed or open position, leading to abnormal prosthesis function. We sought to determine the clinical implications of immobile leaflets seen on intraoperative echocardiography.

METHODS

Patients with immobile leaflets identified on intra-operative/procedure echocardiography immediately post implantation between 2009-2020 were identified from an institutional database. All echocardiograms were reviewed de-novo to confirm immobile leaflets in the immediate post-implantation period. Identified cases were matched 1:2 to controls for age; sex; prosthesis position, model and size; and implantation approach (surgical vs. transcatheter).  Nominal logistic regression and proportional hazards were used to analyze outcomes.

RESULTS

Thirty patients with immobile leaflets immediately post-bioprosthesis implantation were included. Clinical characteristics are summarized in the Table. Immobile leaflets were documented in procedural reports in only 18 (60%) patients. Moderate stenosis was present intraoperatively in 1 patient, none demonstrated ≥moderate regurgitation, and none resulted in immediate corrective action. In 3 (10%), valve re-intervention was required within 30 days due to symptomatic prosthesis dysfunction. Presence of restricted leaflet motion was associated with higher need for post-operative extracorporeal membrane oxygenation use (odds-ratio 7.3, p = 0.02) and composite end-point of death, valve re-replacement, prosthesis thrombosis, or cardiac hospitalizations (risk ratio 2.1, p = 0.03, Figure).

CONCLUSION

Immobile leaflet(s) immediately post-bioprosthetic valve implantation is an uncommon, under-reported, and under-treated phenomenon. Even in the absence of significant prosthetic valve dysfunction, it can be associated with worse post-operative course as well as worse outcomes.

Baseline characteristics Age 76 (67-84) Sex, male 10 (33%) Surgical approach 25 (83%) Aortic 5 (17%) Mitral 12 (40%) Tricuspid 12 (40%) Pulmonary 1 (3%) Re-intervention within 10 days 3 (10%) Numbers are presented as median (interquartile range) or number (percentage). Abstract Figure. Clinical outcome of stuck leaflets

Defining echocardiographic reference values of LV volume indices and biventricular strain in obese patients with normal ejection fraction in different cardiac remodeling patterns – a single center study

Background

The left ventricle (LV) in obese patients undergoes different patterns of remodeling in order to normalize wall stress. However, little is known about how LV volume indices, LV global longitudinal strain and right ventricular free wall strain (GLS) vary according to the pattern of LV remodeling.

Aim

To define the echocardiographic reference values of LV volumes and biventricular GLS across the different LV remodeling patterns in obese patients with a preserved ejection fraction.

Methods

2393 adult obese patients (1428 females, 965 males) with a normal ejection fraction who underwent echocardiography from January 2008 to December 2018 were selected. They were categorized according to 4 cardiac remodeling groups defined by LV mass index (102g/m2 in males, 88g/m2 in females) and relative ventricular wall thickness (0.42): normal geometry (NG), eccentric hypertrophy (EH), concentric remodeling (CR) and concentric hypertrophy (CH). Obese subjects were further categorized by BMI class (30–35, 35–40, >40 kg/m2). Obese subjects were gender matched to controls with a normal BMI (18.5–25 kg/m2) and normal cardiac geometry. Mean ± SD, One-way Anova and Tukey- Kramer HSD were applied. P<0.05 is considered significant.

Results

The mean age of controls and obese patients' were 50±16 and 57±13.6 years respectively (P<0.0001). LV GLS for controls compared to obese subjects with NG, EH, CR and CH was −21.1±2 vs. −20.2±1.9, −19.6±2.8, −18.5±2.9, −17.5±3.4 respectively (p<0.0001 for all), and for RV GLS it was −27.9±4 vs −26.7±3.9, −25.1±5, −23.5±5.5, −24.1±5.2 respectively (p<0.01 for all, except for NG where p=0.2). The distribution of LV indices according to cardiac remodeling subtypes is shown in the figure. Indexed end diastolic and end systolic volumes were smaller in NG, CH and CR compared to controls (p<0.001 for each respectively). LV GLS and ejection fraction were higher in females, while indexed LV volumes were higher in males within each remodeling category (P<0.0001). No significant difference in LV GLS or indexed LV volume was seen across BMI categories within each remodeling pattern (P>0.05). Obese subjects with CH had the highest incidence of the cardiovascular risk factors hyperlipidemia, hypertension and history of myocardial infarction or stroke, compared to those with other remodeling patterns (p<0.0001 for each, vs. NG, EH and CR).

Conclusion

To our knowledge, this is the largest study to define LV volumes and left and right ventricular GLS according to LV remodeling pattern and BMI category. The Lowest GLS was noted in CH. Ejection fraction was similar across the LV remodeling patterns. There were no differences in GLS and LV indexed volumes across BMI categories within each remodeling group. These results can be applied as a reference values for the obese population with a normal LV ejection fraction.

Funding Acknowledgement

Type of funding source: None

Beat-to-beat variability in the tricuspid annulus dimensions and dynamics is markedly increased in atrial fibrillation

Background

Atrial fibrillation (Afib) leads to beat-to-beat variability in cycle length; however, whether there is associated beat-to-beat variability in the tricuspid annulus (TA) dimensions or variability in the time in cardiac cycle when TA reaches maximal size is unknown.

Purpose

We aim to assess the beat-to-beat variability in the TA dimensions in Afib compared with sinus rhythm (SR).

Methods

Images were obtained from 58 patients (29 in Afib, 29 in SR) undergoing either 3D TTE or TEE examination. We measured TA in 3–6 cardiac cycles per patient using commercially available software (TomTec 4MV).

Results

Median absolute difference in maximal TA area over 3–6 cardiac cycles was 1.60 cm2 (range 0.35 cm2 to 4.08 cm2) in Afib vs. 1.17 cm2 (range 0.32 cm2 to 2.19 cm2) in SR, p=0.0063. Median absolute difference in the maximal circumference was 0.79 cm (range 0.09 cm to 2.2 cm) in Afib vs 0.54 cm (range 0.12 cm to 1.43 cm) in SR, p=0.0175. A total of 118 cardiac cycles were analyzed in patients in SR and 147 in Afib. Timing of maximal TA area was most commonly recorded at end-diastole (80–100% of the R-R interval) in 62% of cycles in SR; however, it was distributed over a broad range in Afib, p<0.0001, [Figure].

Conclusion

Afib leads to significant beat-to-beat variability in the maximal TA area, minimal TA area, maximal TA circumference, and in the time of maximal TA area. These findings suggest that accurate assessment of TA dimensions should be based on continuous tracking of the TA over several cardiac cycles, especially in patients with Afib. These observations have significant implications for device sizing in percutaneous tricuspid valve interventions.

Timing of Maximal TA Area

Funding Acknowledgement

Type of funding source: None

Left ventricular filling pressure and survival following aortic valve replacement for severe aortic stenosis

OBJECTIVE

To determine whether echocardiography-derived left ventricular filling pressure influences survival in patients with severe aortic stenosis (AS) undergoing aortic valve replacement (AVR).

METHODS

We retrospectively reviewed 1383 consecutive patients with severe AS, normal ejection fraction and interpretable filling pressure undergoing AVR. Left ventricular filling pressure was determined according to current guidelines using mitral inflow, mitral annular tissue Doppler, estimated right ventricular systolic pressure and left atrial volume index. Cox proportional hazards regression was used to assess the influence of various parameters on mortality.

RESULTS

Age was 75±10 years and 552 (40%) were female. Left ventricular filling pressure was normal in 325 (23%), indeterminate in 463 (33%) and increased in 595 (43%). Mean follow-up was 7.3±3.7 years, and mortality was 1.2%, 4.2% and 18.9% at 30 days and 1 and 5 years, respectively. Compared with patients with normal filling pressure, patients with increased filling pressure were older (78±9 vs 70±12, p<0.001), more often female (45% vs 35%, p=0.002) and were more likely to have New York Heart Association class III-IV symptoms (35% vs 24%, p=0.004), coronary artery disease (55% vs 42%, p<0.001) and concentric left ventricular hypertrophy (63% vs 37%, p<0.001). After correction for other factors, increased left ventricular filling pressure remained an independent predictor of mortality after successful AVR (adjusted HR 1.45 (95% CI 1.16 to 1.81), p=0.005).

CONCLUSIONS

Preoperative increased left ventricular filling pressure is common in patients with AS undergoing AVR and has important prognostic implications, regardless of symptom status. Future prospective studies should consider whether patients with increased filling pressure would benefit from earlier operation.

1049 High single-beat Doppler signals in low-gradient aortic stenosis are associated with higher aortic valve calcium

Funding Acknowledgements

Mayo Clinic

Background

Variability in Doppler signals is common in patients with atrial fibrillation (AF) and AF is common in low-gradient AS (LGAS). Presence of high single beat Doppler signals (peak velocity ≥4m/s or mean gradient ≥40mmHg) is not factored into decision-making in low-gradient aortic stenosis (LGAS).

Objective

Determine prevalence of at least one high Doppler signal in AF LGAS and its relationship to computed tomography aortic valve calcium score (AVCS) versus sinus rhythm (SR) high-gradient aortic stenosis (HGAS).

Methods

Consecutive patients with aortic valve area ≤1cm2 and left ventricular ejection fraction ≥50% during echo were identified (January 1, 2012-December 31, 2016). At least three consecutive Doppler signals were averaged in sinus rhythm (SR) and five in atrial fibrillation (AF).

Results

Of 1,854 patients, age 76± 11 years, male 52%, 301/1,854 (16%) were in AF and LGAS was present in 122/301 (41%). At least one high Doppler signal in AF LGAS was present in 43/122 (35%). AVCS within 1 year of echo was available for 36% of patient with SR HGAS and 34% of AS LGAS. Median AVCS was not different in SR HGAS 2424 (IQR 1623, 3445) vs AF LGAS with at least one high Doppler signal 2509 [IQR1547, 3119], p =0.10 AVCS threshold for severe AS (men &gt;2000 women &gt;1200) was met in 80% SR HGAS vs 86% AF LGAS with high signals.

Conclusions

High Doppler signals in AF LGAS are associated with high AVCS more frequently exceeding thresholds for severe AS. Single-beat high Doppler signals instead of the average correlate better with AVCS and classic HGAS.

A Dangerous Dilemma: Thrombus in Transit During Pregnancy

Pregnancy is associated with venous thromboembolism. Occasionally, thrombus can become entrapped across a patent foramen ovale, with risk of systemic embolism. This report presents a case of a pregnant woman who had thrombus in transit diagnosed by echocardiography, which was successfully removed by surgical thrombectomy. (Level of Difficulty: Intermediate.)

P2447Defining the values of left ventricular ejection fraction, volumes and strain by 2-dimensional echocardiography in subjects with normal cardiac geometry - a single center study

Background

Left ventricular ejection fraction (LVEF), end diastolic, end systolic volumes (EDV, ESV) and global longitudinal strain (GLS) are very important parameters that are frequently reported in cardiology. Normal cardiac geometry was not considered in articles that published normal values. It is important to know normal parameters for population studies. Our hypothesis is to analyze how EF, volumes and GLS may vary by age groups, gender and BMI in a population with normal cardiac geometry.

Purpose

To define the values in EF, volumes and GLS measurements in a healthy population with normal cardiac geometry stratified by age groups, gender and body mass index (BMI).

Methods

This is a single center retrospective study conducted from 2008 to 2018. We selected 4557 subjects (2605 females, 1952 males) >18 years with ≤ mild valvular heart disease, who underwent 2D-echocardiography (2DE) at Mayo clinic, Rochester. All selected subjects had normal LV geometry (i.e., LV mass index≤88g/m2 in females and ≤102g/m2 in males and relative wall thickness ≤0.42 measured by 2DE) and without any cardiovascular risk factors or structural or functional abnormality determined by 2DE. Based on age groups, gender and BMI, we assessed the variability in volumes indexed to body surface area, EF and GLS by Mean ± SD and two sample t-test.

Results

Mean age was 54±15 years (females = 53±15, males = 56±16), body surface area was 1.9 m2±0.2 (females = 1.8±0.2, males = 2.1±0.2), LV GLS −20.7% ±2 SD (females = −21.2±2, males= −20.2±1.9) ranging −16.1 to −27.6 in both genders (Figure); LVEF by Biplane volume method 62.6% ± 4 SD (females = 63±4.3, males=62±4.5). The end diastolic volume 63.6±11.7 cc/m2 (female = 59.9±10.3, males = 68.1±11.8) and end systolic volume 23.9 cc/m2±5.4 (female = 22.3±4.8, males = 25.9±5.5). LV GLS, Biplane EF values were higher in females and EDV and ESV values were higher in males. LV GLS values decreased with age in females (P<0.0001). While EF increased with age in both genders (P<0.0001), EDV and ESV values decreased with age (P<0.0001). When each gender is sub-divided based on their BMI (<25 and ≥25), GLS, EDV and ESV values were higher in population with BMI <25 (P<0.0001).

Normal geometry variables

Conclusion

To our knowledge, this is the biggest single center study to evaluate LV GLS values, LV EF, ED, ES volumes. These results can be used as reference values in a normal population.

Acknowledgement/Funding

None

3260Prognostic value of cardiac power reserve in patients with normal left ventricular ejection fraction undergoing exercise stress echocardiography

Background

Cardiac power output-to-mass (CPOM) ratio is a measure of myocardial performance that incorporates both pressure and flow output, normalized to left ventricular (LV) mass generating that cardiac work. Prior small studies have shown that CPOM predicts outcomes in patients with ischemic cardiomyopathy and reduced LV ejection fraction (EF). We sought to evaluate the prognostic significance of peak exercise CPOM and power reserve (increase from rest to peak exercise) in patients with normal EF.

Methods and results

Retrospective study in 24,783 patients (age 59±13 years, 45% females) with EF≥50% and no significant valve disease or right ventricular (RV) dysfunction, undergoing exercise stress echocardiography between 2004–2018. CPOM was calculated as previously described (0.222 x cardiac output x mean blood pressure / LV mass) and expressed in Watts/100g myocardium. Power reserve was calculated as difference in CPOM between peak stress and rest. All-cause mortality was the primary endpoint. Patients were divided into quartiles of power reserve. Patients with higher power reserve were younger, had higher blood pressure and heart rate, lower LV mass, and lower prevalence of prior myocardial infarction. (Table). During follow-up (median (IQR) 3.9 (0.6–8.3) years), 931 (3.8%) patients died. Progressively lower power reserve was associated with increasing mortality (Figure A). Compared to patients with abnormal stress test, patients with the lowest power reserve but otherwise normal stress test had the same survival as those with infarction/cardiomyopathy or ischemia on stress test (Figure B). Resting CPOM had lower predictive value. After adjusting for age, sex, METs achieved, ischemia/infarction on stress test results, and diastolic function grade, both peak exercise CPOM and power reserve were independent predictors of mortality (p<0.0001), incremental to conventional measures.

Conclusion

Cardiac power output and reserve measured during exercise stress echo provides independent prognostic information in patients with normal resting EF and no significant valve disease or RV dysfunction. The survival of patients with low power reserve but normal stress test was similar to patients with prior infarction/ cardiomyopathy or ischemia on stress test.

6098The role of diastolic function in risk stratification of patients with moderate aortic stenosis

Background

Currently data on the risk stratification of patients with moderate aortic stenosis (AS) are very limited.

Method

Patients diagnosed with moderate AS in 2012 (aortic valve area [AVA]: >1 and ≤1.5cm2) were identified. Patients were stratifying by LV diastolic function (normal vs high filling pressure), left ventricular ejection fraction (LVEF ≥50 vs <50%) and stroke volume index (SVI ≥35 vs <35 ml/m2). High filling pressure was defined as average E/e' ≥14 or septal E/e' ≥11 when atrial fibrillation was present. The prognosis was compared to age- and sex-matched general population.

Results

898 patients were included (age 74 years, 58% male, AVA 1.25 cm2). During a median follow-up of 2.9 years, there were 346 deaths. In patients with moderate AS, mortality was higher than expected (P<0.001, Fig 1A). LV high filling pressure, LVEF<50% and SVI<35ml/m2 were present in 416 (55%), 140 (17%) and 81 (9%) patients, respectively. Those with normal filling pressure had similar prognosis when compared to controls (Fig 1C, P=0.35); whereas mortality rates remained higher than reference even when LVEF≥50% or SVI≥35ml/m2 (Fig 1E, 1G, P<0.001). Amongst all groups, mortality rates were the highest in patients with LVEF <50% or SVI <35 ml/m2 (Fig 1D, 1F, P<0.001); mortality ratios were 3.78 (95% CI 3.01–4.67) and 6.91 (95% CI 5.13–9.11), respectively. Noteworthy, high filling pressure allowed further risk stratification when LVEF or SVI was preserved (Fig 2, P<0.001).

Figures 1 & 2

Conclusions

Patients with moderate AS showed poor survival. A clinical trial examining role of aortic valve replacement would be beneficial not only in patients with reduced LVEF or SVI but also in those with high LV filling pressures.

P323Haemodynamic implications of mitral regurgitation in heart failure with preserved ejection fraction

Background

Mild to moderate mitral regurgitation (MR) is a common finding in heart failure with preserved ejection fraction (HFpEF). MR is often considered to be an innocent bystander, yet little data is available regarding its implications.

Aim

Determine the pathophysiologic correlates of MR in HFpEF

Methods

We retrospectively studied 280 patients with invasively proven HFpEF. MR was absent (None or trivial) in 163 subjects (Non-MR-HFpEF), and present in 117 (MR-HFpEF; 78 mild and 39 moderate MR). 247 subjects also underwent invasive cardiopulmonary exercise testing.

Results

At rest, MR-HFpEF subjects displayed higher pulmonary artery pressures (PAP), PCWP, and pulmonary vascular resistance (PVR; Table). During exercise, PAP and PCWP were not significantly different among groups, but MR-HFpEF displayed reduced ability to enhance cardiac output (CO) in response to heightened metabolic demand (oxygen consumption, VO2; Figure).

Baseline characteristics and haemodynamic characterization at baseline and peak exercise Baseline characteristics Non-MR-HFpEF (N=163) MR-HFpEF (N=117) p value Age 66±11 71±10 0.0002 Female (%) 56 69 0.02 AFib (%) 13 38 <0.0001 Nt proBNP 192 [66, 557] 870 [401, 2135] <0.0001 E/E' 12.3±5.5 15.6±7.2 0.0006 LVEF (%) 64±6 62±6 0.0001 RV fractional area change (%) 51±9 47±10 0.0001 Mean PA (mmHg) 25±7 28±9 0.001 Mean PCWP (mmHg) 15±5 17±6 0.0002 PVR (Woods) 2.0±1.1 2.5±1.4 0.015 CO (L/min) 5.5±1.6 4.8±1.3 0.12 Peak exercise hemodynamics Non-MR-HFpEF (N=152) MR-HFpEF (N=95) p value Mean PA (mmHg 45±10 46.5±10 0.07 Mean PCWP (mmHg) 32±6 31±6 0.6 PVR (Woods) 1.8±1.6 2.7±2.4 0.002 CO (L/min) 9.1±3 7.2±3 0.01 P value adjusted for age, gender and BMI.

CO change in response to VO2 increase

Conclusion

The presence of even mild MR in HFpEF is associated with more adverse hemodynamics, greater pulmonary vascular dysfunction and impaired CO reserve with exercise. Further study is required to better understand the natural history and treatment for MR in HFpEF.

Acknowledgement/Funding

None