Transcatheter aortic valve implantation in patients with high-risk symptomatic native aortic regurgitation (ALIGN-AR): a prospective, multicentre, single-arm study

BACKGROUND

Surgery remains the only recommended intervention for patients with native aortic regurgitation. A transcatheter therapy to treat patients at high risk for mortality and complications with surgical aortic valve replacement represents an unmet need. Commercial transcatheter heart valves in pure aortic regurgitation are hampered by unacceptable rates of embolisation and paravalvular regurgitation. The Trilogy transcatheter heart valve (JenaValve Technology, Irvine, CA, USA) provides a treatment option for these patients. We report outcomes with transfemoral transcatheter aortic valve implantation (TAVI) in patients with pure aortic regurgitation using this dedicated transcatheter heart valve.

METHODS

The ALIGN-AR trial is a prospective, multicentre, single-arm study. We recruited symptomatic patients (aged ≥18 years) with moderate-to-severe or severe aortic regurgitation at high risk for mortality and complications after surgical aortic valve replacement at 20 US sites for treatment with the Trilogy transcatheter heart valve. The 30-day composite primary safety endpoint was compared for non-inferiority with a prespecified performance goal of 40·5%. The primary efficacy endpoint was 1-year all-cause mortality compared for non-inferiority with a performance goal of 25%. This trial is registered with ClinicalTrials.gov, NCT04415047, and is ongoing.

FINDINGS

Between June 8, 2018, and Aug 29, 2022, we screened 346 patients. We excluded 166 (48%) patients and enrolled 180 (52%) patients with symptomatic aortic regurgitation deemed high risk by the heart team and independent screening committee assessments. The mean age of the study population was 75·5 years (SD 10·8), and 85 (47%) were female, 95 (53%) were male, and 131 (73%) were White. Technical success was achieved in 171 (95%) patients. At 30 days, four (2%) deaths, two (1%) disabling strokes, and two (1%) non-disabling strokes occurred. Using standard Valve Academic Research Consortium-2 definitions, the primary safety endpoint was achieved, with events occurring in 48 (27% [97·5% CI 19·2-34·0]) patients (pnon-inferiority<0·0001), with new pacemaker implantation in 36 (24%) patients. The primary efficacy endpoint was achieved, with mortality in 14 (7·8% [3·3-12·3]) patients at 1 year (pnon-inferiority<0·0001).

INTERPRETATION

This study shows the safety and effectiveness of treating native aortic regurgitation using a dedicated transcatheter heart valve to treat patients with symptomatic moderate-to-severe or severe aortic regurgitation who are at high risk for mortality or complications after surgical aortic valve replacement. The observed short-term clinical and haemodynamic outcomes are promising as are signs of left ventricular remodelling, but long-term follow-up is necessary.

FUNDING

JenaValve Technology.

Transesophageal Echocardiographic Planning and Neo-Left Ventricular Outflow Tract Assessment for Transcatheter Mitral Valve Implantation Using Novel Software

•New echo software aids periprocedural screening before transcather MV implantation. •Virtual valve can be directly projected in the 3D datasets. •It may be useful for patients unable to undergo contrast-enhanced CCT scans.

Presence and Relevance of Myocardial Bridge in LAD-PCI of CTO and Non-CTO Lesions

BACKGROUND

Intravascular ultrasound (IVUS) studies show that one-quarter of left anterior descending (LAD) arteries have a myocardial bridge. An MB may be associated with stent failure when the stent extends into the MB.

OBJECTIVES

The aim of this study was to investigate: 1) the association between an MB and chronic total occlusion (CTO) in any LAD lesions; and 2) the association between an MB and subsequent clinical outcomes after percutaneous coronary intervention in LAD CTOs.

METHODS

A total of 3,342 LAD lesions with IVUS-guided percutaneous coronary intervention (280 CTO and 3,062 non-CTO lesions) were included. The primary outcome was target lesion failure (cardiac death, target vessel myocardial infarction, definite stent thrombosis, and ischemic-driven target lesion revascularization).

RESULTS

An MB by IVUS was significantly more prevalent in LAD CTOs than LAD non-CTOs (40.4% [113/280] vs 25.8% [789/3,062]; P < 0.0001). The discrepancy in CTO length between angiography and IVUS was greater in 113 LAD CTOs with an MB than 167 LAD CTOs without an MB (6.0 [Q1, Q3: 0.1, 12.2] mm vs 0.2 [Q1, Q3: -1.4, 8.4] mm; P < 0.0001). Overall, 48.7% (55/113) of LAD CTOs had a stent that extended into an MB after which target lesion failure was significantly higher compared to a stent that did not extend into an MB (26.3% vs 0%; P = 0.0004) or compared to an LAD CTO without an MB (26.3% vs 9.6%; P = 0.02).

CONCLUSIONS

An MB was more common in LAD CTO than non-CTO LAD lesions. If present, approximately one-half of LAD CTOs had a stent extending into an MB that, in turn, was associated with worse outcomes.

Ostial right coronary artery lesion morphology and outcomes after treatment with drug-eluting stents

BACKGROUND

Outcomes after percutaneous coronary intervention (PCI) for de novo ostial right coronary artery (RCA) lesions are poor.

AIMS

We used intravascular ultrasound (IVUS) to clarify the morphological patterns of de novo ostial RCA lesions and their associated clinical outcome.

METHODS

Among 5,102 RCA IVUS studies, 170 de novo ostial RCA stenoses (within 3 mm from the aorto-ostium) were identified. These were classified as 1) isolated ostial lesions (no disease extending beyond 10 mm from the ostium and without a calcified nodule [CN]); 2) ostial CN, typically with diffuse disease (disease extending beyond 10 mm); and 3) ostial lesions with diffuse disease but without a CN. The primary outcome was target lesion failure (TLF: cardiac death, target vessel myocardial infarction, definite stent thrombosis, and ischaemia-driven target lesion revascularisation).

RESULTS

The prevalence of an isolated ostial lesion was 11.8% (n=20), 47.6% (n=81) were ostial CN, and 40.6% (n=69) were ostial lesions with diffuse disease. Compared to ostial lesions with diffuse disease, isolated lesions were more common in women (75.0% vs 42.0%; p=0.01), and CN were associated with older age (median [first, third quartile] 76 [70, 83] vs 69 [63, 81] years old; p=0.002). The Kaplan-Meier rate of TLF at 2 years was significantly higher in patients with CN (21.6%) compared to diffuse lesions (8.2%) (p=0.04), and patients with isolated lesions had no events. A multivariable Cox proportional hazard model revealed that CN were significantly associated with TLF (hazard ratio 6.63, 95% confidence interval: 1.28-34.3; p=0.02).

CONCLUSIONS

Ostial RCA lesions have specific morphologies - detectable by IVUS - that may be associated with long-term clinical outcomes.

Right ventricular remodeling and clinical outcomes following transcatheter tricuspid valve intervention

AIMS

Characterize the impact of residual tricuspid regurgitation (TR) on right ventricle (RV) remodeling and clinical outcomes after transcatheter tricuspid valve intervention.

METHODS

We performed a single-center retrospective analysis of transcatheter tricuspid valve repair (TTVr) or replacement (TTVR) patients. The primary outcomes were longitudinal tricuspid annular plane systolic excursion (TAPSE), fractional area change (FAC), pulmonary artery systolic pressure (PASP), and RV dimensions (RVd). We used multivariable linear mixed models to evaluate association with replacement versus repair and degree of TR reduction with changes in these echo measures over time. Multivariable Cox regression was used to identify associations between changes in these echo measures and a composite clinical outcome of death, heart failure hospitalization, or re-do tricuspid valve intervention.

RESULTS

We included a total of 61 patients; mean age was 77.5 ± 11.7 and 62% were female. TTVR was performed in 25 (41%) and TTVr in 36 (59%). Initially, 72% (n = 44) had ≤ severe TR and 28% (n = 17) had massive or torrential TR. The median number of follow up echos was 2: time to 1st follow-up was 50 days (interquartile range [IQR]: 20, 91) and last follow-up was 147 (IQR: 90, 327). Median TR reduction was 1 (IQR: 0, 2) versus 4 (IQR: 3, 6) grades in TTVr versus TTVR (p < 0.0001). In linear mixed modeling, TTVR was associated with decline in TAPSE and PASP, and TR reduction was associated with decreased RVd. In multivariable Cox regression, greater RVd was associated with the clinical outcome (hazard ratio: 9.27, 95% confidence interval: 1.23-69.88, p = 0.03).

CONCLUSION

Greater TR reduction is achieved by TTVR versus TTVr, which is in turn associated with RV reverse remodeling. RV dimension in follow-up is associated with increased risk of a composite outcome of death, heart failure hospitalization, or re-do tricuspid valve intervention.

Transcatheter transseptal treatment of patients with severe mitral regurgitation using an atrial fixation mitral valve replacement technology

BACKGROUND

Mitral regurgitation (MR) is the most common valvular heart disease worldwide with a 5-year mortality rate of 50 % with medical therapy alone. Several transcatheter mitral valve replacement (TMVR) devices are being investigated in clinical trials. Early evidence has demonstrated clinical benefits with a reduction in heart failure symptoms, low rates of residual MR, and reverse remodeling of the left ventricle (LV) over time. However, high anatomical screen failure rates limit its applicability. The primary reasons for the anatomical screen failure are risk of LV outflow tract obstruction, large mitral valve annulus size, and the presence of mitral annular calcification. Our clinical experiences using an atrial only fixation TMVR technology delivered via a transfemoral-transseptal approach is described.

METHODS

Three consecutive patients with severe functional MR underwent TMVR implantation using an atrial only fixation technology and a low-profile transseptal delivery system.

RESULTS

Technical success was achieved in 100 % of the patients with a clinically significant reduction in MR. Longer-term follow-up (up to 6-months) has demonstrated a sustained reduction in MR and significant improvement in quality of life for all patients.

CONCLUSIONS

Longer-term outcomes in our patients showed persistent reduction in MR, sustained implant performance, and notable improvements in NYHA Class and quality of life. There were no major adverse events. Follow-up CT data showed no evidence of device-related thrombosis, with stable valve position and integrity. The atrial fixation TMVR technology may have benefits in preserving the dynamics of the native mitral valve annulus thereby reducing the overall risk of LVOT obstruction.

SHORT ABSTRACT

We present a single-center experience of three consecutive patients with severe functional MR treated with the AltaValve using a low-profile transseptal delivery system. A clinically significant reduction in mitral regurgitation was achieved in all patients, and longer-term follow-up has demonstrated sustained clinical benefits.

Imaging Methods for Evaluation of Chronic Aortic Regurgitation in Adults: JACC State-of-the-Art Review

A global multidisciplinary workshop was convened to discuss the multimodality diagnostic evaluation of aortic regurgitation (AR). Specifically, the focus was on assessment tools for AR severity and analyzing evolving data on the optimal timing of aortic valve intervention. The key concepts from this expert panel are summarized as: 1) echocardiography is the primary imaging modality for assessment of AR severity; however, when data is incongruent or incomplete, cardiac magnetic resonance may be helpful; 2) assessment of left ventricular size and function is crucial in determining the timing of intervention; 3) recent evidence suggests current cutpoints for intervention in asymptomatic severe AR patients requires further scrutiny; 4) left ventricular end-systolic volume index has emerged as an additional parameter that has promise in guiding timing of intervention; and 5) the role of additional factors (including global longitudinal strain, regurgitant fraction, and myocardial extracellular volume) is worthy of future investigation.

Transfemoral Transcatheter Mitral Valve Implantation With a Dedicated Device in a Rheumatic Mitral Stenosis Patient

A 65-year-old obese woman with rheumatic heart disease and restrictive lung disease presented with decompensated heart failure. Evaluation demonstrated severely thickened mitral valve leaflets, severe mitral stenosis, and moderate mitral regurgitation. She underwent successful transfemoral transseptal transcatheter mitral valve replacement with a dedicated valve resulting in improved functional status. (Level of Difficulty: Advanced.).

Transcatheter aortic valve-in-valve implantation within stentless landing zones: Procedural insights from a single-center experience

BACKGROUND

Valve-in-valve (VIV) transcatheter aortic valve implantation (TAVI) is a less invasive therapeutic option compared with redo surgical valve replacement for high-risk patients. Relative to procedures within stented surgical valves, VIV-TAVI within stentless valves is associated with a higher complication rate due to challenging underlying anatomy and absence of fluoroscopic landmarks.

AIMS

We share a single-center experience with VIV-TAVI in stentless valves, discussing our procedural insights and associated outcomes.

METHODS

Our institutional database was queried, and 25 patients who had undergone VIV-TAVI within a stentless bioprosthesis, homograft, or valve-sparing aortic root replacement between 2013 and 2022 were found. Outcome endpoints were based on the Valve Academic Research Consortium-3 criteria.

RESULTS

The mean age of the cohort was 69.5 ± 13.6 years. VIV implantation was performed within a homograft in 11 patients, a stentless bioprothesis in 10 patients, and a valve-sparing aortic root replacement in 4 patients. Nineteen (76%) balloon-expandable valves, 5 (20%) self-expanding valves, and one mechanically-expandable (4%) valve were implanted with 100% procedural success, with no instances of significant paravalvular leak, coronary occlusion, or device embolization. There was one (4%) in-hospitality mortality after an emergency procedure; one (4%) patient experienced a transient ischemic attack; and two (8%) patients required permanent pacemaker implantation. The median length of hospital stay was 2 days. After a median follow-up time of 16.5 months, valve function was acceptable in all patients with available data.

CONCLUSION

VIV-TAVI within stentless valves can be safely performed with methodical procedural technique and can provide clinical benefit in patients at high reoperation risk.

Mechanisms and treatment outcomes of ostial right coronary artery in-stent restenosis

BACKGROUND

Despite a high rate of in-stent restenosis (ISR) after stenting the right coronary artery (RCA) ostium, the mechanism of ostial RCA ISR is not well understood.

AIMS

We aimed to clarify the cause of ostial RCA ISR using intravascular ultrasound (IVUS).

METHODS

Overall, 139 ostial RCA ISR lesions were identified with IVUS, pre-revascularisation. Primary ISR mechanisms were classified as follows: 1) neointimal hyperplasia (NIH); 2) neoatherosclerosis; 3) ostium not covered by the stent; 4) stent fracture or deformation; 5) stent underexpansion (old minimum stent area <4.0 mm² or stent expansion <50%); or 6) a protruding calcified nodule.

RESULTS

The median duration from prior stenting was 1.2 (first quartile 0.6, third quartile 3.1) years. The primary mechanisms of ISR were NIH in 25% (n=35) of lesions, neoatherosclerosis in 22% (n=30), uncovered ostium in 6% (n=9) (biological cause 53%, n=74), stent fracture or deformation in 25% (n=35), underexpansion in 11% (n=15), and protruding calcified nodules in 11% (n=15) (mechanical cause 47%, n=65). Including secondary mechanisms, 51% (n=71) of ostial RCA ISRs had stent fractures that were associated with greater hinge motion of the ostial-aorta angle during the cardiac cycle. The Kaplan-Meier rate of target lesion failure at 1 year was 11.5%. When the mechanically caused ISRs were treated without new stents, they suffered a higher subsequent event rate (41.4%) compared with non-mechanical causes or mechanical causes treated without restenting (7.8%, unadjusted hazard ratio 6.44, 95% confidence interval: 2.33-17.78; p<0.0001).

CONCLUSIONS

Half of the ostial RCA ISRs were due to mechanical causes. Subsequent event rates were high, especially in mechanically caused ISRs treated without the implantation of a new stent.

Zero-Contrast Left Atrial Appendage Occlusion Using a Hybrid Echocardiography-Fluoroscopy Technique Without Iodinated Contrast

Contrast exposure during left atrial appendage occlusion may be harmful in those with chronic kidney disease or allergy. This single-center registry (n = 31) demonstrates the feasibility and safety of zero-contrast percutaneous left atrial appendage occlusion using echocardiography, fluoroscopy, and fusion imaging, with 100% procedural success and no device complications at 45 days.

An Unusual Cause of Shortness of Breath: Pulmonary Vein Stenosis After Surgical Mitral Valve Replacement

A 79-year-old man with prior bioprosthetic mitral valve replacement presented with progressive shortness of breath and was found to have right upper pulmonary vein stenosis and paravalvular leak diagnosed with the use of multimodal imaging. The patient underwent balloon angioplasty, stenting of the pulmonary vein, and paravalvular leak closure with ultimate resolution of symptoms. (Level of Difficulty: Intermediate.).

Endovascular eSheath Predilation to Facilitate Transfemoral Transcatheter Aortic Valve Delivery

Iliofemoral anatomy plays an important role in determining transfemoral (TF) transcatheter aortic valve replacement candidacy. Herein, we present the novelty of endovascular eSheath balloon dilation to facilitate valve delivery. This technique, in addition to or instead of intravascular lithotripsy, may facilitate TF valve delivery in patients who do not otherwise meet traditional criteria for TF access.

Three-year survival of transcatheter versus surgical aortic valve replacement in dialysis

To highlight the trends of surgical (open) aortic valve replacement (SAVR) as well as to compare the outcome between transcatheter aortic valve replacement (TAVR) and SAVR in elderly dialysis patients. TAVR has evolved as an effective alternative to surgery (SAVR) for aortic stenosis. We identified dialysis-dependent patients who underwent SAVR or TAVR from 2000 to 2015 from the United States Renal Data System using ICD-9 codes. We defined high-risk surgical patients as age over 70 or older. The primary endpoint was survival at 3 years and we compared the outcome between SAVR and TAVR groups using inverse probability of treatment weighting (IPTW). A total of 4332 and 1280 dialysis patients underwent SAVR and TAVR, respectively, during the study period. Among SAVR cohort, 3312 patients underwent SAVR before June 2012 and 1020 after June 2012. In-hospital mortality was significantly worse before 2012 (14.6% vs. 11.3% after 2012, p = 0.007) as well as estimated 3-year mortality (69.1% vs. 60.3% after 2012, p < 0.001). After June 2012, the TAVR cohort was older and had more comorbidities including coronary artery disease and congestive heart failure compared to the SAVR cohort. After IPTW, in-hospital mortality was significantly lower after TAVR versus SAVR (odds ratio 0.38 [95% confidence interval [CI], 0.27-0.52], p < 0.001). However, TAVR had a significantly higher risk of 3-year mortality than SAVR (hazard ratio 1.24 [95% CI 1.1-1.39], p < 0.001). TAVR may be a reasonable and potentially preferable alternative to SAVR in the elderly dialysis population in the short-term period.

Impact of inferior vena cava entry characteristics on tricuspid annular access during transcatheter interventions

OBJECTIVES

The purpose of this study was to characterize the anatomic relationship between the inferior vena cava (IVC) and tricuspid annulus (TA) and its potential impact on the performance of transcatheter TV interventions.

BACKGROUND

Transcatheter tricuspid valve (TV) interventions are emerging as a therapeutic alternative for the treatment of severe, symptomatic tricuspid regurgitation (TR). Progression of TR is associated with right heart dilatation. These anatomic changes may distort the IVC-TA relationship and impact successful implantation of transcatheter devices.

METHODS

Fifty patients who presented with symptomatic TR for consideration of transcatheter TV therapy with an available CT were included in the study. Comprehensive transesophageal echocardiogram and CT analyses were performed to assess the right-sided cardiac chambers, TA and IVC-TA relationship.

RESULTS

The mean age of the study cohort was 78.4 ± 8.9 years. Torrential TR was present in 54% (n = 27). There was considerable variation in the short axis mid-IVC to mid-TA offset (SAX_MID 18.2 ± 7.9 mm, range 4.7-42.1 mm).

CONCLUSIONS

The IVC-to-TA relationship exhibits significant variability in patients with symptomatic TR. CT analysis of the tricuspid anatomy, including the relationship to the surrounding structures and the IVC, is essential for planning transcatheter TV interventions. Further studies are needed to define whether the IVC-to-TA relationship is a predictor of technical success in the context of specific transcatheter delivery systems.

First Transfemoral Implantation of a Novel Transcatheter Valve in an LVAD Patient With Aortic Insufficiency

An 80-year-old man with a destination left ventricular assist device (LVAD) presented with decompensated heart failure. Evaluation demonstrated numerous LVAD high power spike events, significant aortic regurgitation, and hemolysis. He underwent successful aortic valve replacement with a novel transcatheter valve and LVAD pump exchange that resulted in an improvement in his clinical status. (Level of Difficulty: Advanced.).

Long-Term Outcomes of Transcatheter Aortic Valve Replacement in Patients With End-Stage Renal Disease

Background

Aortic stenosis is prevalent in end‐stage renal disease. Transcatheter aortic valve replacement (TAVR) is a plausible alternative for surgical aortic valve replacement. However, little is known regarding long‐term outcomes in patients with end‐stage renal disease who undergo TAVR.

Methods and Results

We identified all patients with end‐stage renal disease who underwent TAVR from 2011 through 2016 using the United States Renal Data System. The primary end point was 5‐year mortality after TAVR. Factors associated with 1‐ and 5‐year mortality were analyzed. A total of 3883 TAVRs were performed for patients with end‐stage renal disease. Mortality was 5.8%, 43.7%, and 88.8% at 30 days, 1 year, and 5 years, respectively. Case volumes increased rapidly from 17 in 2011 to 1495 in 2016. Thirty‐day mortality demonstrated a dramatic reduction from 11.1% in 2012 to 2.5% in 2016 (P=0.01). Age 75 or older (hazard ratio [HR], 1.14; 95% CI, 1.05–1.23 [P=0.002]), body mass index <25 (HR, 1.18; 95% CI, 1.08–1.28 [P<0.001]), chronic obstructive pulmonary disease (HR, 1.25; 95% CI, 1.1–1.35 [P<0.001]), diabetes mellitus as the cause of dialysis (HR, 1.22; 95% CI, 1.11–1.35 [P<0.001]), hypertension as the cause of dialysis (HR, 1.17; 95% CI, 1.06–1.29 [P=0.004]), and White race (HR, 1.17; 95% CI, 1.06–1.3 [P=0.002]) were independently associated with 5‐year mortality.

Conclusions

Short‐term outcomes of TAVR in patients with end‐stage renal disease have improved significantly. However, long‐term mortality of patients on dialysis remains high.

Suprasternal Versus Transfemoral Access for Transcatheter Aortic Valve Replacement: Insights From a Propensity Score Matched Analysis

Background Suprasternal access is an alternative access strategy for transcatheter aortic valve replacement (TAVR) where the innominate artery is cannulated from an incision above the sternal notch. To date, suprasternal access has never been compared with transfemoral TAVR. Thus, we sought to assess safety, feasibility, and early clinical outcomes between suprasternal and transfemoral access for patients undergoing TAVR. Methods and Results We evaluated patients from 2 institutional prospective, observational registries containing 1348 patients. Patients were selected in a 2:1 ratio (transfemoral:suprasternal) on the basis of propensity score matching. The primary outcome was in-hospital mortality, and secondary outcomes included the incidence of ischemic stroke, major bleeding, vascular injury, left bundle-branch block, and permanent pacemaker implantation at 30-day follow-up. Propensity score matching identified 89 patients undergoing suprasternal TAVR and 159 patients undergoing transfemoral TAVR suitable for analysis. There was no significant difference between suprasternal TAVR and transfemoral TAVR with respect to in-hospital mortality (1.1% versus 0.6%; odds ratio [OR], 1.80; 95% CI, 0.11-29.06; P=0.680). No patients in either cohort suffered an ischemic stroke. The incidence of major bleeding (2.2% versus 2.5%; OR, 0.89; 95% CI, 0.16-4.96; P=0.895) and vascular injury (1.1% versus 1.9%; OR, 0.59; 95% CI, 0.06-5.77; P=0.651) did not differ significantly. The frequency of left bundle-branch block (9.4% versus 15.8%; OR, 0.56; 95% CI, 0.24-1.30; P=0.177) and permanent pacemaker implantation (11.2% versus 5.9%; OR, 2.01; 95% CI, 0.75-5.45; P=0.169) were not statistically significantly different. Conclusions Suprasternal TAVR was safe and achieved promising short-term clinical outcomes when compared with transfemoral TAVR. Future studies seeking to identify the optimal alternative access site should evaluate suprasternal TAVR access alongside other substitutes for transfemoral TAVR.

Impact of renin-angiotensin system inhibitors on clinical outcomes in patients with severe aortic stenosis undergoing transcatheter aortic valve replacement: an analysis of from the PARTNER 2 trial and registries

AIMS

Left ventricular pressure overload is associated with activation of the cardiac renin-angiotensin system, which may contribute to myocardial fibrosis and worse clinical outcomes. We sought to assess the association between treatment with angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin II receptor blockers (ARBs) at baseline and clinical outcomes in patients with symptomatic, severe aortic stenosis (AS) undergoing transcatheter aortic valve replacement (TAVR) in the PARTNER 2 trial and registries.

METHODS AND RESULTS

A total of 3979 intermediate, high, or prohibitive risk patients who underwent TAVR in the PARTNER 2 trial and registries (excluding the valve in valve registry) were included in the study. Clinical outcomes at 2 years were compared according to baseline ACEI/ARB treatment status using Kaplan-Meier event rates and study-stratified multivariable Cox proportional hazards regression models. Sensitivity analysis was conducted using propensity score matching. Of 3979 patients who were included in the current analysis, 1736 (43.6%) were treated and 2243 (56.4%) were not treated with ACEI/ARB at baseline. Treatment with ACEI/ARB was associated with lower 2-year all-cause mortality (18.6% vs. 27.5%, P < 0.0001), cardiovascular mortality (12.3% vs. 17.9%, P < 0.0001), and non-cardiovascular mortality (7.2% vs. 11.7%, P < 0.0001). Angiotensin-converting enzyme inhibitor/ARB treatment at baseline remained independently associated with a lower hazard of 2-year all-cause and cardiovascular mortality after multivariable adjustment, and propensity score matching.

CONCLUSION

In a large cohort of patients with severe symptomatic AS from the PARTNER 2 trial and registries, ACEI/ARB treatment at baseline was independently associated with a lower risk of 2-year all-cause and cardiovascular mortality.

Mitral valve-in-valve and valve-in-ring: tips, tricks, and outcomes

Transcatheter aortic valve implantation is now a mainstay of treatment in patients with aortic stenosis who are considered intermediate, high and prohibitive risk for surgery. Extended use of this innovative platform in treating other conditions has led to its approval in treating degenerated aortic bioprosthesis. Similarly, use of transcatheter devices in treating degenerated mitral bioprosthesis and failed mitral valve repairs with annuloplasty rings has opened a potential alternative to surgery in these patients. Experience in mitral valve-in-valve (MVIV) and valve-in-ring (VIR), while still limited, is on the rise. Although similar in many ways to the aortic VIV, it is different with respect to patient selection, planning and procedural steps. Familiarity with the bioprosthetic properties and dimensions can help an operator choose an appropriate transcatheter device and deploy it in an ideal position. Due to greater variability in construction and properties, mitral rings have led to poorer results compared to mitral valve-in-valve. Understanding the properties of mitral rings is critical and has been simplified by us in a stepwise manner. We also describe steps in patient preparation and procedure, which should help operators in performing this procedure. Certain unique complications, such as left ventricular outflow tract obstruction and risk of embolization, are discussed with tips to address these issues. Once these steps are followed, the procedure can be performed with minimal risk and good outcome.

Urologic Complications in Patients Receiving Indwelling Urinary Catheters During Transcatheter Aortic Valve Replacement

OBJECTIVES

The minimalist approach to transcatheter aortic valve replacement (TAVR) focuses on avoiding extraneous invasive measures. Data describing the clinical impact of routine indwelling urinary catheter (IUC) in TAVR patients is limited. We sought to examine outcomes after IUC placement in patients undergoing TAVR.

METHODS

We performed a retrospective analysis of 773 consecutive patients undergoing TAVR between 2011 and 2015. Patients were excluded who did not receive an IUC, had a pre-existing IUC, had renal replacement therapy, or underwent non-transfemoral TAVR. Patients were classified by presence of the composite of in-hospital urologic adverse events (UAEs), defined as urinary retention, IUC reinsertion, discharge with IUC, new hematuria, or urinary tract infection (UTI). The primary study endpoint was all-cause mortality at 1 year.

RESULTS

A total of 520 patients met study criteria and were analyzed. The incidence of UAE was 28.6%. Urinary retention after IUC removal occurred in 14.6% of patients. UTIs occurred in 6.5% and acute kidney injury occurred in 13.6% of IUC patients. UAE was associated with an increased rate of 30-day and 1-year all-cause mortality (hazard ratio [HR], 2.84; 95% confidence interval [CI], 1.09-7.35; P=.02 and HR, 1.96; 95% CI, 1.22-3.16; P<.01, respectively). After multivariable adjustment for important baseline differences, UAEs were associated with significantly greater hazard of 1-year mortality (adjusted HR, 1.79; 95% CI, 1.07-2.99; P=.03) but not 30-day mortality (adjusted HR, 1.96; 95% CI, 0.67-5.49; P=.22).

CONCLUSION

UAEs were frequent in patients receiving an IUC during TAVR and were associated with substantial morbidity, as well as longer hospital stay. Further research is required to establish whether avoidance of IUC as a component of the minimalist approach will reduce UAEs.

Impact of the COVID-19 pandemic on interventional cardiology fellowship training in the New York metropolitan area: A perspective from the United States epicenter

Background

The healthcare burden posed by the coronavirus disease 2019 (COVID‐19) pandemic in the New York Metropolitan area has necessitated the postponement of elective procedures resulting in a marked reduction in cardiac catheterization laboratory (CCL) volumes with a potential to impact interventional cardiology (IC) fellowship training.

Methods

We conducted a web‐based survey sent electronically to 21 Accreditation Council for Graduate Medical Education accredited IC fellowship program directors (PDs) and their respective fellows.

Results

Fourteen programs (67%) responded to the survey and all acknowledged a significant decrease in CCL procedural volumes. More than half of the PDs reported part of their CCL being converted to inpatient units and IC fellows being redeployed to COVID‐19 related duties. More than two‐thirds of PDs believed that the COVID‐19 pandemic would have a moderate (57%) or severe (14%) adverse impact on IC fellowship training, and 21% of the PDs expected their current fellows' average percutaneous coronary intervention (PCI) volume to be below 250. Of 25 IC fellow respondents, 95% expressed concern that the pandemic would have a moderate (72%) or severe (24%) adverse impact on their fellowship training, and nearly one‐fourth of fellows reported performing fewer than 250 PCIs as of March 1st. Finally, roughly one‐third of PDs and IC fellows felt that there should be consideration of an extension of fellowship training or a period of early career mentorship after fellowship.

Conclusions

The COVID‐19 pandemic has caused a significant reduction in CCL procedural volumes that is impacting IC fellowship training in the NY metropolitan area. These results should inform professional societies and accreditation bodies to offer tailored opportunities for remediation of affected trainees.

Risk-Benefit Profile of Longer-Than-1-Year Dual-Antiplatelet Therapy Duration After Drug-Eluting Stent Implantation in Relation to Clinical Presentation

BACKGROUND

We sought to determine whether the risks and benefits of prolonging dual-antiplatelet therapy (DAPT) beyond 1 year after drug-eluting stent implantation depend on clinical presentation in a meta-analysis of randomized controlled trials.

METHODS AND RESULTS

Randomized controlled trials comparing ≤1- versus >1-year DAPT after drug-eluting stent placement were searched through MEDLINE, EMBASE, Cochrane databases, and proceedings of international meetings. The primary efficacy end point was myocardial infarction, whereas the primary safety end point was major bleeding. Net clinical benefit was defined as the composite of myocardial infarction or major bleeding. Outcomes were analyzed according to patient presentation with stable ischemic heart disease versus acute coronary syndromes. The meta-analysis included 6 trials with a total of 21 457 patients, including 14 132 with stable ischemic heart disease and 7325 with acute coronary syndrome. After a median follow-up of 19.5 months, ≤1-year DAPT was associated with higher rates of myocardial infarction compared with >1-year DAPT (hazard ratio [HR], 1.63; 95% CI, 1.37-1.95), with no interaction apparent between treatment effect and clinical presentation. Shorter DAPT was associated with reduced rates of major bleeding compared with longer DAPT (HR, 0.64; 95% CI, 0.42-0.99) with no significant interaction between treatment effect and clinical presentation. However, a net clinical benefit of >1-year DAPT was present in patients with acute coronary syndrome (HR of shorter versus longer DAPT, 1.59; 95% CI, 1.24-2.02) but not in those with stable ischemic heart disease (HR, 1.15; 95% CI, 0.89-1.51; P_interaction=0.04). Shorter DAPT was also associated with lower rates of noncardiac mortality compared with longer DAPT (HR, 0.71; 95% CI, 0.52-0.96), with no significant interaction between treatment effect and clinical presentation ( P_interaction=0.12).

CONCLUSIONS

Compared with ≤1-year DAPT, >1-year DAPT reduces the risk of myocardial infarction but increases the risk of major bleeding and noncardiac mortality. A net clinical benefit of extended DAPT was apparent for patients with acute coronary syndrome but not for those with stable ischemic heart disease.

Low and elevated B-type natriuretic peptide levels are associated with increased mortality in patients with preserved ejection fraction undergoing transcatheter aortic valve replacement: an analysis of the PARTNER II trial and registry

Aims

B-type natriuretic peptide (BNP) is a cardiac neurohormone that is secreted in response to ventricular volume expansion and pressure overload. There are conflicting data regarding the association between BNP levels and outcomes after transcatheter aortic valve replacement (TAVR). We therefore sought to assess the association between baseline BNP and adverse outcomes in patients with symptomatic, severe aortic stenosis (AS), and left ventricular ejection fraction (LVEF) ≥50%, undergoing TAVR in the PARTNER 2 Trial and Registry.

Methods and results

A total of 1782 patients were included in the analysis, and BNP was evaluated both as a continuous log-transformed value and by a priori categories: low (&lt;50 pg/mL), normal (≥50 and &lt;100 pg/mL), moderately elevated (≥100 and &lt;400 pg/mL), or markedly elevated (≥400 pg/mL). Clinical outcomes from discharge to 2 years were compared between patients according to their baseline BNP level, using Kaplan–Meier event rates and multivariable Cox proportional hazards regression models. After adjustment, spline curves revealed a non-linear association between log-transformed BNP and all-cause and cardiovascular mortality in which both the lowest and highest values were associated with increased mortality. Two-year all-cause mortality rates for those with low (n = 86), normal (n = 202), moderately elevated (n = 885), and markedly elevated (n = 609) baseline BNP were 20.0%, 9.8%, 17.7%, and 26.1%, respectively. In adjusted models, compared to a normal baseline BNP, low [adjusted hazard ratio (HR) 2.6, 95% confidence interval (CI) 1.3–5.0, P-value 0.005], moderately elevated (adjusted HR 1.6, 95% CI 1.0–2.6, P-value 0.06), and markedly elevated (adjusted HR 2.1, 95% CI 1.3–3.5, P-value 0.003) BNP were associated with increased all-cause mortality, driven by cardiovascular mortality.

Conclusions

In a large cohort of patients with severe symptomatic AS and preserved LVEF undergoing TAVR, all-cause and cardiovascular mortality rates at 2 years were higher in patients with low and markedly elevated BNP levels.

Clinical Trial Registration

https://clinicaltrials.gov/ unique identifier #NCT01314313, #NCT02184442, #NCT03222128, and #NCT03222141.

Experimental Evaluation of a Novel Percutaneous Transseptal Catheter-Based Mitral Valve Replacement Technology

BACKGROUND

Transcatheter mitral valve replacement is a novel therapeutic approach aiming to treat patients with severe mitral regurgitation. This study aimed to evaluate the biological and technical performance of a novel transseptal transcatheter mitral valve replacement system (Cephea Valve Technologies, Santa Cruz, CA) in a preclinical model.

METHODS

Biological performance and healing response were evaluated following open-heart surgical implantation procedures in 10 sheep utilizing an antegrade transatrial access. Valve performance was assessed with fluoroscopy, echocardiography, and histology at 30 (n=2), 60 (n=3), and 90 days (n=5). Feasibility of transseptal valve delivery and performance was tested acutely in 10 pigs.

RESULTS

In the chronic studies, all animals survived without problems until completion of the study. The hemodynamics of the study valves were excellent with low rates of paravalvular leak. There was no left ventricular outflow tract obstruction. Pathological evaluation showed excellent position and condition of the mitral implants without evidence for thrombosis, endocarditis, or excessive calcification. Subsequently, mitral valves were implanted in 10 pigs using a dedicated transseptal delivery system. The implants remained in stable position with excellent hemodynamic profile. Correct valve position and function was confirmed by echocardiography and autopsy.

CONCLUSIONS

The transseptal delivery of the Cephea transcatheter mitral valve replacement system in an experimental model was feasible and safe. The chronic studies demonstrated a favorable healing response. Further human studies are needed to evaluate the performance of this novel valve system in patients with severe mitral regurgitation.

Optimizing Cardiac CT Protocols for Comprehensive Acquisition Prior to Percutaneous MV and TV Repair/Replacement

Clinical trials of transcatheter mitral valve and tricuspid valve repair and replacement devices have begun in earnest, with the ultimate goal of providing definitive, nonsurgical treatment for the millions of patients with severe, symptomatic regurgitation, many of whom are too high risk or inoperable for a surgical approach. Computed tomography (CT) angiography offers the potential for detailed anatomic assessment in this patient population, but its optimal implementation for patients with mitral and tricuspid disease requires patient-centered protocol specification reflecting the goal of the scan, an understanding of complex anatomy and pathophysiology, and particulars of CT scanner capabilities. In this paper, the need for new interventional approaches to mitral and tricuspid valve disease is discussed, followed by a detailed review of how to perform a high-quality CT angiography examination, taking into consideration scanner- and patient-specific variables when preparing a pre-mitral or tricuspid protocol. The many possible clinical challenges affecting the performance of cardiac and vascular CT angiography for pre-procedure mitral and tricuspid repair/replacement are reviewed and specific tips, trouble-shooting approaches, and recommendations are provided for how to conduct the best-quality study, be it at an experienced imaging center with the most advanced scanner or at a novice center using an earlier generation CT platform.

Imaging in patients with severe mitral annular calcification: insights from a multicentre experience using transatrial balloon-expandable valve replacement

Aims

To investigate valve sizing and the haemodynamic relevance of the predicted left ventricular outflow tract (LVOT) in patients with mitral annular calcification (MAC) undergoing transatrial transcatheter valve implantation (THV).

Methods and results

In total, 21 patients undergoing transatrial THV, multiplanar reconstruction (MPR), maximum intensity projection (MIP), and cubic spline interpolation (CSI) were compared for MA sizing during diastole. In addition, predicted neo-LVOT areas were measured in 18 patients and correlated with the post-procedural haemodynamic dimensions. The procedure was successful in all patients (100%). Concomitant aortic valve replacement was performed in eight patients (43%) (AVR group). Sizing using MPR and MIP yielded comparable results in terms of area, perimeter, and diameter, whereas the dimensions obtained with CSI were systematically smaller. The simulated mean systolic neo-LVOT area was 133.4 ± 64.2 mm2 with an anticipated relative LVOT area reduction (neo-LVOT area/LVOT area × 100) of 59.3 ± 14.7%. The systolic relative LVOT area reduction, but not the absolute neo-LVOT area, was found to predict the peak (r = 0.69; P = 0.002) and mean (r = 0.65; P = 0.004) post-operative aortic gradient in the overall population as well as separately in the AVR (peak: r = 0.91; P = 0.002/mean: r = 0.85; P = 0.002) and no-AVR (peak: r = 0.89; P = 0.003/mean: r = 0.72; P = 0.008) groups.

Conclusion

In patients with severe MAC undergoing transatrial transcatheter valve implantation, MPR, and MIP yielded comparable annular dimensions, while values obtained with CSI tended to be systematically smaller. Mitral annular area and the average annular diameter appear to be reliable parameters for valve selection. Simulated relative LVOT reduction was found to predict the post-procedural aortic gradients.

Transcatheter Versus Surgical Aortic Valve Replacement in Patients With Prior Cardiac Surgery in the Randomized PARTNER 2A Trial

OBJECTIVES

The aim of this study was to further evaluate clinical outcomes in patients with and without PCS.

BACKGROUND

Prior cardiac surgery (PCS) is associated with increased surgical risk and post-operative complications following surgical aortic valve replacement (SAVR), but whether this risk is similar in transcatheter aortic valve replacement (TAVR) is unclear.

METHODS

In the PARTNER 2A (Placement of Aortic Transcatheter Valve) trial, 2,032 patients with severe aortic stenosis at intermediate surgical risk were randomized to TAVR with the SAPIEN XT valve or SAVR. Adverse clinical outcomes at 30 days and 2 years were compared using Kaplan-Meier event rates and multivariate Cox proportional hazards regression models. The primary endpoint of the PARTNER 2 trial was all-cause death and disabling stroke.

RESULTS

Five hundred nine patients (25.1%) had PCS, mostly (98.2%) coronary artery bypass grafting. There were no significant differences between TAVR and SAVR in patients with or without PCS in the rates of the primary endpoint at 30 days or 2 years. Nevertheless, an interaction was observed between PCS and treatment arm; whereas no-PCS patients treated with TAVR had higher rates of 30-day major vascular complications than patients treated with SAVR (adjusted hazard ratio: 2.66; 95% confidence interval: 1.68 to 4.22), the opposite was true for patients with PCS (adjusted hazard ratio: 0.27; 95% confidence interval: 0.11 to 0.66) (p_interaction <0.0001). A similar interaction was observed for life-threatening or disabling bleeding.

CONCLUSIONS

In the PARTNER 2A trial of intermediate-risk patients with severe aortic stenosis undergoing SAVR versus TAVR, the relative risk for 2-year adverse clinical outcomes was similar between TAVR and SAVR in patients with or without PCS.

Injuries to the Aorta, Aortic Annulus, and Left Ventricle During Transcatheter Aortic Valve Replacement

The experience with transcatheter aortic valve replacement is increasing worldwide; however, the incidence of potentially catastrophic cardiac or aortic complications has not decreased. In most cases, significant injuries to the aorta, aortic valve annulus, and left ventricle require open surgical repair. However, the transcatheter aortic valve replacement patient presents a unique challenge as many patients are at high or prohibitive surgical risk and, therefore, an open surgical procedure may not be feasible or appropriate. Consequently, prevention of these potentially catastrophic injuries is vital, and practitioners need to understand when open surgical repair is required and when alternative management strategies can be used. The goal of this article is to provide an overview of current management and prevention strategies for major complications involving the aorta, aortic valve annulus, and left ventricle.

Impact of Methodologic Differences in Three-Dimensional Echocardiographic Measurements of the Aortic Annulus Compared with Computed Tomographic Angiography Before Transcatheter Aortic Valve Replacement

BACKGROUND

Three-dimensional (3D) echocardiographic (3DE) imaging is an alternative to multi-detector row computed tomography (MDCT) for aortic annular measurement before transcatheter aortic valve replacement (TAVR). A commonly used direct planimetry from a reconstructed short-axis view has not been compared with semiautomated 3DE methods. Typically accepted optimal cutoffs for percent prosthesis-area oversizing of the balloon-expandable SAPIEN or SAPIEN XT valve to native annular size are approximately 5% to 15%. The aim of this study was to compare semiautomated and direct planimetric 3DE methods for aortic annular sizing with a gold standard of MDCT to determine predictive value for paravalvular regurgitation (PVR) and balloon postdilatation.

METHODS

In this retrospective analysis, aortic annular cross-sectional area was measured from pre-TAVR imaging using (1) MDCT (CT_Area), (2) a 3D transesophageal echocardiographic (TEE) semiautomated method (3DE_Area_SA), and (3) a 3D TEE direct planimetric method (3DE_Area_Direct). Annular area percent oversizing was calculated. PVR after TAVR was assessed from intraoperative TEE imaging. Need for balloon postdilatation was recorded.

RESULTS

One hundred patients who underwent TAVR with either the SAPIEN or SAPIEN XT balloon-expandable prosthesis were analyzed. Twenty-three patients had mild or greater PVR after TAVR. CT_Area was 442 ± 79 mm², 3DE_Area_SA was 435 ± 81 mm², and 3DE_Area_Direct was 429 ± 82 mm². Both 3DE_Area_SA and 3DE_Area_Direct underestimated MDCT (P < .05). All methods were highly correlative (R = 0.88-0.93, P < .0001). Percent oversizing obtained by the three methods significantly predicted mild or greater PVR and need for balloon postdilatation by receiver operating characteristic analysis, with optimal cutoffs for CT_Area (9%-10%) and 3DE_Area_SA (14%) within the recommended ranges for the studied transcatheter valves and for 3DE_Area_Direct higher than the recommended range (18%-19%). Inter- and intraobserver reproducibility were lowest for 3DE_Area_Direct.

CONCLUSIONS

Caution must be used when using 3D TEE direct planimetry of the aortic annulus, as optimal percent oversizing ranges approach the level associated with root injury, and measurements are less reproducible. Therefore, semiautomated 3DE planimetry is preferred to 3DE direct planimetry for aortic annulus sizing.

Practical considerations for optimizing cardiac computed tomography protocols for comprehensive acquisition prior to transcatheter aortic valve replacement

Transcatheter aortic valve replacement (TAVR) is performed frequently in patients with severe, symptomatic aortic stenosis who are at high risk or inoperable for open surgical aortic valve replacement. Computed tomography angiography (CTA) has become the gold standard imaging modality for pre-TAVR cardiac anatomic and vascular access assessment. Traditionally, cardiac CTA has been most frequently used for assessment of coronary artery stenosis, and scanning protocols have generally been tailored for this purpose. Pre-TAVR CTA has different goals than coronary CTA and the high prevalence of chronic kidney disease in the TAVR patient population creates a particular need to optimize protocols for a reduction in iodinated contrast volume. This document reviews details which allow the physician to tailor CTA examinations to maximize image quality and minimize harm, while factoring in multiple patient and scanner variables which must be considered in customizing a pre-TAVR protocol.

The incretin effect in obese adolescents with and without type 2 diabetes: impaired or intact?

The incretin effect reflects the actions of enteral stimuli to promote prandial insulin secretion. Impairment of this measure has been proposed as an early marker of β-cell dysfunction and described in T2D, IGT, and even obesity without IGT. We sought to determine the effects of obesity and diabetes on the incretin effect in young subjects with short exposures to metabolic abnormalities and a few other confounding medical conditions. Subjects with T2D (n = 10; 18.0 ± 0.4 yr) or NGT, either obese (n = 11; 17.7 ± 0.4 yr) or lean (n = 8; 26.5 ± 2.3 yr), had OGTT and iso-iv. The incretin effect was calculated as the difference in insulin secretion during these tests and was decreased ∼50% in both the NGT-Ob and T2D subjects relative to the NGT-Ln group. The T2D group had impaired glucose tolerance and insulin secretion during the OGTT, whereas the lean and obese NGT subjects had comparable glucose excursions and β-cell function. During the iso-iv test, the NGT-Ob subjects had significantly greater insulin secretion than the NGT-Ln and T2D groups. These findings demonstrate that in young subjects with early, well-controlled T2D the incretin effect is reduced, similar to what has been described in diabetic adults. The lower incretin effect calculated for the obese subjects with NGT is driven by a disproportionately greater insulin response to iv glucose and does not affect postprandial glucose regulation. These findings confirm that the incretin effect is an early marker of impaired insulin secretion in persons with abnormal glucose tolerance but suggest that in obese subjects with NGT the incretin effect calculation can be confounded by exaggerated insulin secretion to iv glucose.

Very low intravenous contrast volume protocol for computed tomography angiography providing comprehensive cardiac and vascular assessment prior to transcatheter aortic valve replacement in patients with chronic kidney disease

BACKGROUND

Transcatheter aortic valve replacement (TAVR) is a lifesaving procedure for many patients high risk for surgical aortic valve replacement. The prevalence of chronic kidney disease (CKD) is high in this population, and thus a very low contrast volume (VLCV) computed tomography angiography (CTA) protocol providing comprehensive cardiac and vascular imaging would be valuable.

METHODS

52 patients with severe, symptomatic aortic valve disease, undergoing pre-TAVR CTA assessment from 2013-4 at Columbia University Medical Center were studied, including all 26 patients with CKD (eGFR<30 mL/min) who underwent a novel VLCV protocol (20 mL of iohexol at 2.5 mL/s), and 26 standard-contrast-volume (SCV) protocol patients. Using a 320-slice volumetric scanner, the protocol included ECG-gated volume scanning of the aortic root followed by medium-pitch helical vascular scanning through the femoral arteries. Two experienced cardiologists performed aortic annulus and root measurements. Vascular image quality was assessed by two radiologists using a 4-point scale.

RESULTS

VLCV patients had mean (±SD) age 86 ± 6.5, BMI 23.9 ± 3.4 kg/m(2) with 54% men; SCV patients age 83 ± 8.8, BMI 28.7 ± 5.3 kg/m(2), 65% men. There was excellent intra- and inter-observer agreement for annular and root measurements, and excellent agreement with 3D-transesophageal echocardiographic measurements. Both radiologists found diagnostic-quality vascular imaging in 96% of VLCV and 100% of SCV cases, with excellent inter-observer agreement.

CONCLUSIONS

This study is the first of its kind to report the feasibility and reproducibility of measurements for a VLCV protocol for comprehensive pre-TAVR CTA. There was excellent agreement of cardiac measurements and almost all studies were diagnostic quality for vascular access assessment.

Sphingosine-1-Phosphate Receptor Agonist Fingolimod Increases Myocardial Salvage and Decreases Adverse Postinfarction Left Ventricular Remodeling in a Porcine Model of Ischemia/Reperfusion

BACKGROUND

Fingolimod, a sphingosine-1-phosphate receptor agonist, is used for the treatment of multiple sclerosis and exerts antiapoptotic properties. We hypothesized that sphingosine-1-phosphate receptor activation with fingolimod during acute myocardial infarction (MI) inhibits apoptosis, leading to increased myocardial salvage, reduced infarct size, and mitigated left ventricular (LV) remodeling in a porcine model of ischemia/reperfusion.

METHODS AND RESULTS

Ischemia/reperfusion was induced in pigs by balloon occlusion of the left anterior descending artery, followed by reperfusion. Animals randomly received fingolimod or saline (control). In short-term experiments, fingolimod treatment activated the cardioprotective reperfusion injury salvage kinase and survivor activating factor enhancement pathways in the infarct border zone 24 hours after MI, leading to decreased cardiomyocyte apoptosis and reduced myocardial oxidative stress. These effects were abolished by specific inhibitors of both pathways, demonstrating that fingolimod-induced cardioprotection was mediated by reperfusion injury salvage kinase and survivor activating factor enhancement pathways. In long-term experiments, fingolimod significantly improved myocardial salvage, reduced infarct size, and improved systolic LV function measured by cardiac magnetic resonance 1 week and 1 month after MI. Importantly, fingolimod mitigated the development of adverse post-MI LV remodeling 1 month after MI. Specifically, fingolimod treatment led to a significant reduction in LV mass, LV dilatation, and neurohormonal activation, and it preserved LV geometry. Furthermore, fingolimod decreased interstitial fibrosis, cardiomyocyte hypertrophy, and chronic activation of Akt and extracellular receptor kinase 1/2 in the remote noninfarcted myocardium.

CONCLUSIONS

Sphingosine-1-phosphate receptor activation with fingolimod during acute MI reduced infarct size via the reperfusion injury salvage kinase and survivor activating factor enhancement pathways, improved systolic LV function, and mitigated post-MI LV remodeling. Our data strongly support a cardioprotective role for sphingosine-1-phosphate receptor activation during MI.