Left atrial pressure and predictors of survival after percutaneous mitral paravalvular leak closure

Association of transcatheter left atrial appendage occlusion with acute changes in left atrial pressure: An invasive hemodynamic study

BACKGROUND

The hemodynamic effects of transcatheter left atrial appendage occlusion (LAAO) remain unclear.

OBJECTIVE

We sought to assess the effect of LAAO on invasive hemodynamics and their correlation with clinical outcomes.

METHODS

We recorded mean left atrial pressure (mLAP) before and after device deployment. We assessed the prevalence and predictors of mLAP increase after deployment, the association between significant mLAP increase after deployment and 45-day peridevice leak (PDL), and the association between mLAP increase and heart failure (HF) hospitalization. A significant mLAP increase was defined as one equal to or greater than the mean percentage increase in mLAP after deployment (≥28%).

RESULTS

We included 302 patients (36.4% female; mean age, 75.8 ± 9.5 years). After deployment, mLAP increased in 48% of patients, 38% of whom experienced significant mLAP increase. Independent predictors of mLAP increase were baseline mLAP ≤14 mm Hg, nonparoxysmal atrial fibrillation, and age per 5 years (odds ratios: 3.66 [95% CI, 2.21-6.05], 1.81 [95% CI, 1.08-3.02], and 0.85 [95% CI, 0.73-0.99], respectively). Significant mLAP increase was an independent predictor of 45-day PDL (odds ratio, 2.55; 95% CI, 1.04-6.26). There was no association between mLAP increase and HF hospitalization.

CONCLUSION

After deployment, mLAP acutely rises in 48% of patients, although this is not associated with increased HF hospitalizations. PDL is more likely to develop at 45 days in patients with significant increase in mLAP after deployment, although most leaks were small (<5 mm). These findings suggest that mLAP increase after deployment is not associated with major safety concerns. Additional studies are warranted to explore the long-term hemodynamic effects of LAAO.

Hemodynamic Predictors of Outcome Following Alcohol Septal Ablation for Hypertrophic Obstructive Cardiomyopathy

BACKGROUND

Alcohol septal ablation (ASA) is a minimally invasive treatment for drug-refractory obstructive hypertrophic cardiomyopathy. Detailed assessment of pressure changes and predictors of mortality and procedure success are not well defined.

METHODS

This is a single-center study evaluating pressure changes and predictors of mortality and procedure success in transseptal ASA. Survival analysis and predictors of mortality were assessed using the Kaplan-Meier analysis and Cox regression, respectively.

RESULTS

A total of 156 patients were included (mean age, 67.3 years; 46.8% women). Left atrial (LA) pressure and left ventricular outflow tract (LVOT) gradient decreased, whereas aortic pulse pressure (PP) increased post-ASA. Patients with lower baseline mean LA pressure (82% (gradient change median), and PP increase >19% (PP change median) had superior survival. On Cox univariable regression, baseline mean LA pressure >median (19 mm Hg; hazard ratio [HR], 2.09 [95% CI, 1.05-4.18]; P=0.036), residual LVOT gradient (HR, 1.02 [95% CI, 1.01-1.03]; P=0.003), and LVOT gradient percent reduction median (28 mm Hg; HR, 2.36 [95% CI, 1.17-4.76]; P=0.016), baseline mean LA pressure >median (19 mm Hg; HR, 2.70 [95% CI, 1.33-5.50]; P=0.006), percentage reduction in gradient

CONCLUSIONS

ASA is associated with an acute decrease in the LVOT gradient and LA pressures and increase in aortic PP. Mean LA pressure, percentage decrease in LVOT gradient, and increase in PP are strong predictors of survival free of all-cause mortality following ASA and are important variables for procedural guidance.

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Key Words

• cardiomyopathy, hypertrophic
• heart atria
• hemodynamics

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MESH Headings

• Humans
• Female
• Aged
• Male
• Treatment Outcome
• Ethanol/adverse effects
• Cardiomyopathy, Hypertrophic/diagnostic imaging
• Cardiomyopathy, Hypertrophic/surgery
• Cardiac Surgical Procedures
• Hemodynamics
• Ablation Techniques/adverse effects

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Affiliation(s)

Mohamad S. Alabdaljabar Departments of Internal Medicine (M.S.A.), Mayo Clinic, Rochester, MN
Emily E. Cendrowski Cardiovascular Medicine (E.E.C., R.A.N., W.R.M., J.B.G., C.S.R., M.F.E.), Mayo Clinic, Rochester, MN
Rick A. Nishimura Cardiovascular Medicine (E.E.C., R.A.N., W.R.M., J.B.G., C.S.R., M.F.E.), Mayo Clinic, Rochester, MN
William R. Miranda Cardiovascular Medicine (E.E.C., R.A.N., W.R.M., J.B.G., C.S.R., M.F.E.), Mayo Clinic, Rochester, MN
Jeffrey B. Geske Cardiovascular Medicine (E.E.C., R.A.N., W.R.M., J.B.G., C.S.R., M.F.E.), Mayo Clinic, Rochester, MN
Charanjit S. Rihal Cardiovascular Medicine (E.E.C., R.A.N., W.R.M., J.B.G., C.S.R., M.F.E.), Mayo Clinic, Rochester, MN
Mackram F. Eleid Cardiovascular Medicine (E.E.C., R.A.N., W.R.M., J.B.G., C.S.R., M.F.E.), Mayo Clinic, Rochester, MN

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Society of thoracic surgeons risk score and left atrial pressure for predicting clinical outcomes among transcatheter mitral edge-to-edge repair patients

BACKGROUND

Limited data exist regarding the performance of the Society of Thoracic Surgeons (STS) risk score among transcatheter mitral edge-to-edge repair (TEER) patients.

OBJECTIVE

Evaluate STS score accuracy, and the incremental value of post-procedural left atrial pressure (LAP).

METHODS

A retrospective analysis of TEER patients between 2013 and 2020. Patients were allocated into 3 groups: high (≥8% [n = 298, 31%]), intermediate (4%-8% [n = 318, 33%]), and low (<4% [n = 344, 36%]). Primary outcomes included 1-year mortality or cardiovascular hospitalizations. Cox proportional hazards regression modeling was used to determine the hazard ratio of the primary outcome, and STS score accuracy was assessed by receiver operating characteristic. A spline curve was used to display the relationship between LAP and the primary endpoint. Continuous net reclassification improvement (NRI) was used to determine the incremental value of LAP.

RESULTS

We included 960 patients, primarily elderly (79 [70-85]), with a median STS risk of 5.6 (3-9). High-risk patients were older (83 [75-89], 81 [74-87], 72 [64-79], p < 0.001), and had more comorbidities compared to intermediate and low-risk groups. Upon Cox regression, STS score (high vs. low: HR 2.5 [1.7-3.8]; Intermediate vs. low: HR 1.8 [1.2-2.7] and LAP HR 1.03 [1.01-1.06], p = 0.007) were associated with the outcome. C statistics analysis revealed low accuracy of the STS score (AUC-0.61 [0.58-0.65, p < 0.001]). Continuous NRI analysis indicated an improvement in risk prediction of 17% (6.9-26.2), p < 0.001.

CONCLUSION

STS risk score has low accuracy in predicting clinical outcomes after TEER. Adding LAP measurements can improve reclassification and identify those prone to adverse outcomes.

Safety, Efficacy and Long-Term Outcomes of Patients Treated with the Occlutech Paravalvular Leak Device for Significant Paravalvular Regurgitation

Between December 2014 and March 2021, 144 patients with aortic (Ao) or mitral (Mi) paravalvular leaks (PVLs) were enrolled at 21 sites in 10 countries. Safety data were available for 137 patients, who were included in the safety analysis fraction (SAF), 93 patients with Mi PVLs and 44 patients with Ao PVLs. The full analysis set (FAS) comprised 112 patients with available stratum (aortic/mitral leak) as well as baseline (BL), 180-day or later assessments (2 years). Procedural success (implantation of the device with a proper closure of the PVL, defined as reduction in paravalvular regurgitation of ≥one grade as assessed by echocardiography post implantation) was achieved in 91.3% of FAS patients with Mi PVLs and in 90.0% of those with Ao PVLs. The proportion of patients suffering from significant or severe heart failure (HF), classified as New York Heart Association (NYHA) class III/IV, decreased from 80% at baseline to 14.1% at 2-year follow-up (FAS). The proportion of FAS patients needing hemolysis-related blood transfusion decreased from 35.5% to 3.8% and from 8.1% to 0% in Mi patients and Ao patients, respectively. In total, 35 serious adverse events (SAEs) were reported in 27 patients (19.7%) of the SAF population. The SAEs considered possibly or probably related to the device included device embolization (three patients), residual leak (two patients) and vascular complication (one patient). During follow-up, 12/137 (8.8%) patients died, but none of the deaths was considered to be device-related. Patients implanted with the Occlutech Paravalvular Leak Device (PLD) showed long-lasting improvements in clinical parameters, including NYHA class and a reduced dependency on hemolysis-related blood transfusions.

The Role of Invasive Hemodynamics in Guiding Contemporary Transcatheter Valvular Interventions

Recent advances in transcatheter interventions have refueled the interest in utilizing invasive hemodynamics in the catheterization laboratory. The authors review contemporary invasive techniques used to confirm valve disease and guide transcatheter valve interventions. They also discuss the available data and the remaining questions on the role of invasive hemodynamics in current practice and in the future.

Computational Fluid Dynamics Simulations of Mitral Paravalvular Leaks in Human Heart

In recent years, computational fluid dynamics (CFD) has been extensively used in biomedical research on heart diseases due to its non-invasiveness and relative ease of use in predicting flow patterns inside the cardiovascular system. In this study, a modeling approach involving CFD simulations was employed to study hemodynamics inside the left ventricle (LV) of a human heart affected by a mitral paravalvular leak (PVL). A simplified LV geometry with four PVL variants that varied in shape and size was studied. Predicted blood flow parameters, mainly velocity and shear stress distributions, were used as indicators of how presence of PVLs correlates with risk and severity of hemolysis. The calculations performed in the study showed a high risk of hemolysis in all analyzed cases, with the maximum shear stress values considerably exceeding the safe level of 300 Pa. Results of our study indicated that there was no simple relationship between PVL geometry and the risk of hemolysis. Two factors that potentially played a role in hemolysis severity, namely erythrocyte exposure time and the volume of fluid in which shear stress exceeded a critical value, were not directly proportional to any of the characteristic geometrical parameters (shape, diameters, circumference, area, volume) of the PVL channel. Potential limitations of the proposed simplified approach of flow analysis are discussed, and possible modifications to increase the accuracy and plausibility of the results are presented.

Long-term outcomes of catheter-based intervention for clinically significant paravalvular leak

BACKGROUND

In most centres, clinically significant percutaneous paravalvular leak (PVL) closure following valve replacement surgery is reserved for those considered high-risk for surgery. There is a paucity of data regarding the long-term outcomes of these patients.

AIMS

Our goals were to assess the long-term outcomes of patients undergoing percutaneous PVL closure.

METHODS

A total of 100 consecutive transcatheter PVL closure procedures (74 mitral, 26 aortic) were performed in 95 patients between February 2005 and August 2019 at our hospital. Data collected included procedural success rates, indication-specific outcomes and mortality.

RESULTS

Mean follow-up was 5.6±6.1 years, mean age 62.6±15.2 years, and 45.4% were female. The device was successfully implanted in 88 procedures (88.0%). Patients who presented with heart failure (n=57) had a significant improvement in NYHA classification (29.2% Class III/IV versus 100.0%, p<0.001). For patients who presented with haemolytic anaemia (n=38), haemoglobin increased (11.94±1.634 vs 9.72±1.49, p<0.001) and LDH levels were reduced (1,354.90±1,225.55 vs 2,039.40±1,347.20, p<0.001) following the procedure. Rates of mortality were 3.8% at 90 days, 15.6% after 1 year, and 27.2% after 5 years.

CONCLUSIONS

For patients who are deemed intermediate- to high-risk for repeat surgery, transcatheter PVL closure shows reasonable clinical success rates, with a significant improvement in symptoms, and a relatively low rate of periprocedural complications.

Hemodynamics rounds: Hemodynamics of mitral valve interventions

Mitral valvulopathy presents as regurgitation, stenosis, or mixed disease and can occur in both native and prosthetic valves. Such disease develops in conjunction with pathophysiologic changes in the left atrium (LA) and drives changes in LA compliance, pressure, and thus clinical syndromes. With advances in the understanding and treatment of structural heart disease and in the setting of higher-risk patient populations, less-invasive transcatheter approaches have become increasingly commonplace in the treatment of mitral valve disease. Over time, transcatheter mitral valve interventions have evolved to include paravalvular leak closure, mitral valve repair, and mitral valve replacement. Parallel to this evolution, advances in invasive intracardiac pressure monitoring, particularly at the level of the LA, have also occurred. These advances emphasize the unique interplay between mitral valve disease and LA function; account for limitations of noninvasive assessment; and guide beneficial outcomes in each area of transcatheter mitral valve intervention. As a result, continuous transseptal LA pressure monitoring has developed into an indispensable instrument in successful percutaneous mitral valve intervention, complementing traditional noninvasive assessment.