Comprehensive Myocardial Assessment by Computed Tomography: Impact on Short-Term Outcomes After Transcatheter Aortic Valve Replacement

BACKGROUND

Quantification of myocardial changes in severe aortic stenosis (AS) is prognostically important. The potential for comprehensive myocardial assessment pre-transcatheter aortic valve replacement (TAVR) by computed tomography angiography (CTA) is unknown.

OBJECTIVES

This study sought to evaluate whether quantification of left ventricular (LV) extracellular volume-a marker of myocardial fibrosis-and global longitudinal strain-a marker of myocardial deformation-at baseline CTA associate with post-TAVR outcomes.

METHODS

Consecutive patients with symptomatic severe AS between January 2021 and June 2022 who underwent pre-TAVR CTA were included. Computed tomography extracellular volume (CT-ECV) was derived from septum tracing after generating the 3-dimensional CT-ECV map. Computed tomography global longitudinal strain (CT-GLS) used semi-automated feature tracking analysis. The clinical endpoint was the composite outcome of all-cause mortality and heart failure hospitalization.

RESULTS

Among the 300 patients (80.0 ± 9.4 years of age, 45% female, median Society of Thoracic Surgeons Predicted Risk of Mortality score 2.80%), the left ventricular ejection fraction (LVEF) was 58% ± 12%, the median CT-ECV was 28.5% (IQR: 26.2%-32.1%), and the median CT-GLS was -20.1% (IQR: -23.8% to -16.3%). Over a median follow-up of 16 months (IQR: 12-22 months), 38 deaths and 70 composite outcomes occurred. Multivariable Cox proportional hazards model, accounting for clinical and echocardiographic variables, demonstrated that CT-ECV (HR: 1.09 [95% CI: 1.02-1.16]; P = 0.008) and CT-GLS (HR: 1.07 [95% CI: 1.01-1.13]; P = 0.017) associated with the composite outcome. In combination, elevated CT-ECV and CT-GLS (above median for each) showed a stronger association with the outcome (HR: 7.14 [95% CI: 2.63-19.36]; P < 0.001).

CONCLUSIONS

Comprehensive myocardial quantification of CT-ECV and CT-GLS associated with post-TAVR outcomes in a contemporary low-risk cohort with mostly preserved LVEF. Whether these imaging biomarkers can be potentially used for the decision making including timing of AS intervention and post-TAVR follow-up will require integration into future clinical trials.

Preprocedural Computed Tomography Planning for Surgical Aortic Valve Replacement

BACKGROUND

Selection of transcatheter valve size using preprocedural computed tomography (CT) is standardized and well established. However, valve sizing for surgical aortic valve replacement (SAVR) is currently performed intraoperatively by using sizers, which may result in variation among operators and risk for prosthesis-patient mismatch. This study evaluated the usefulness of CT annulus measurement for SAVR valve sizing.

METHODS

This study included patients who underwent SAVR using Inspiris or Magna Ease and received preoperative electrocardiogram-gated CT imaging. Starting from June 2022, study investigators applied a CT sizing algorithm using CT-derived annulus size to guide minimum SAVR label size. The final decision of valve selection was left to the operating surgeon during SAVR. The study compared the appropriateness of valve selection (comparing implanted size with CT-predicted size) and prosthesis-patient mismatch rates without aortic root enlargement between 2 cohorts: 102 cases since June 2022 (CT sizing cohort) and 180 cases from 2020 to 2021 (conventional sizing cohort).

RESULTS

Implanted size smaller than CT predicted size and severe prosthesis-patient mismatch were significantly lower by CT sizing than by conventional sizing (12% vs 31% [P = .001] and 0% vs 6% [P = .039], respectively). Interoperator variability was a factor associated with implanted size smaller than CT predicted with conventional sizing, whereas it became nonsignificant with CT sizing.

CONCLUSIONS

Applying CT sizing to SAVR led to improved valve size selection, less prosthesis-patient mismatch, and less interoperator variability. CT sizing for SAVR could also be used to predict prosthesis-patient mismatch before SAVR and identify patients who need aortic root enlargement.

Deformation of transcatheter heart valves with mitral valve-in-valve

BACKGROUND

The use of oversizing in mitral valve-in-valve (MViV) procedures can lead to non-uniform expansion of transcatheter heart valves (THV). This may have implications for THV durability.

AIMS

The objective of this study was to assess the extent and predictors of THV deformation in MViV procedures.

METHODS

We examined 33 patients who underwent MViV with SAPIEN prostheses. The extent of THV deformation (deformation index, eccentricity, neosinus volume, asymmetric leaflet expansion and vertical deformation) and hypoattenuating leaflet thickening (HALT) were assessed using cardiac computed tomography (CT), performed prospectively at 30 days post-procedure. For descriptive purposes, the THV deformation index was calculated, with values >1.00 representing a more hourglass shape.

RESULTS

Non-uniform underexpansion of THV was common after MViV implantation, with a median expansion area of 74.0% (interquartile range 68.1-84.1) at the narrowest level and a THV deformation index of 1.21 (1.13-1.29), but circularity was maintained with eccentricity ranging from 0.24 to 0.28. The degree of oversizing was a key factor associated with greater underexpansion and a higher deformation index (β=-0.634; p<0.001; β=0.594; p<0.001, respectively). Overall, the incidence of HALT on the 30-day postprocedural CT was 27.3% (9 of 33). Most patients (32 of 33) were on anticoagulation therapy, but the prothrombin time and international normalised ratio (PT-INR) at the time of the CT scan was <2.5 in 23 of 32 patients. Among patients with a PT-INR of <2.5, HALT was predominantly observed with a high THV deformation index of ≥1.18.

CONCLUSIONS

THV deformation, i.e., underexpansion and an hourglass shape, commonly occurs after MViV implantation and is negatively affected by excessive oversizing. Optimising THV expansion during MViV could potentially prevent HALT.

Feasibility of Redo-Transcatheter Aortic Valve Replacement in Sapien Valves Based on In Vivo Computed Tomography Assessment

BACKGROUND

Our aim was to assess the feasibility of repeat transcatheter aortic valve (TAV) replacement for degenerated Sapien3 (S3) prostheses by simulating subsequent implantation of S3 or Evolut, using in vivo computed tomography-based sizing and the impact on coronary and patient-prosthesis mismatch risks.

METHODS

Computed tomography scans from 356 patients with prior S3 TAV replacement implantation were analyzed. The in vivo sizing for second TAV based on averaged area of 3 levels of outflow, mid (narrowest) and inflow, was compared with in vitro recommendations, that is, same size as index S3 for second S3 and 1 size larger for Evolut. Risks of coronary obstruction and patient-prosthesis mismatch were determined by valve-to-aorta distance and estimated effective orifice area, respectively.

RESULTS

Overall, the majority of patients (n=328; 92.1%) had underexpanded index S3 with an expansion area of 94% (91%-97%), leading to significant differences in size selection of the second TAV between in vivo and in vitro sizing strategies. Expansion area <89% served as a threshold, resulting in 1 size smaller than the in vitro recommendations were selected in 45 patients (13%) for S3-in-S3 and 13 (4%) for Evolut-in-S3, while the remaining patients followed in vitro recommendations (P<0.01, in vivo versus in vitro sizing). Overall, 57% of total patients for S3-in-S3 simulation and 60% for Evolut-in-S3 were considered low risk for coronary complications. Deep index S3 implantation (odds ratio, 0.76 [interquartile range, 0.67-0.87]; P<0.001) and selecting Evolut as the second TAV (11% risk reduction in intermediate- or high-risk patients) reduced coronary risk. Estimated moderate or severe patient-prosthesis mismatch risk was 21% for S3-in-S3 and 1% for Evolut-in-S3, assuming optimal expansion of the second TAV.

CONCLUSIONS

Redo-TAV replacement with S3-in-S3 and Evolut-in-S3 could be feasible with low risk to coronaries in ≈60% of patients, while the remaining 40% will be at intermediate or high risk. The feasibility of redo-TAV replacement is influenced by sizing strategy, type of second TAV, native annular anatomy, and implant depth.

Deformation of Transcatheter Heart Valve Following Valve-in-Valve Transcatheter Aortic Valve Replacement: Implications for Hemodynamics

BACKGROUND

Valve-in-valve (ViV) transcatheter aortic valve replacement (TAVR) may be associated with adverse hemodynamics, which might affect clinical outcomes.

OBJECTIVES

This study sought to evaluate the extent and predictors of transcatheter heart valve (THV) deformity in ViV TAVR and the relation to postprocedural hemodynamics.

METHODS

We examined 53 patients who underwent ViV TAVR in surgical heart valves with self-expanding Evolut prostheses. THV deformation was examined using cardiac computed tomography prospectively performed 30 days after ViV TAVR, and correlated with 30-day echocardiographic hemodynamic data.

RESULTS

Near complete expansion of the functional portion of the implanted ViV prostheses (ie, >90%) was observed in 16 (30.2%) patients. Factors related to greater expansion of the functional portion and consequently larger neosinus volume were absence of polymer surgical frame, higher implantation and use of balloon aortic valvuloplasty or bioprosthetic valve fracture during the procedure (all P < 0.05). Underexpansion of the functional portion, but not the valve inflow frame, was closely associated with mean gradient and effective orifice area at 30 days on echocardiography, with and without adjustment for the sizes of the THV and surgical heart valve.

CONCLUSIONS

Underexpansion of the functional portion of THV prostheses is common during ViV TAVR, occurs more frequently with deep implantation and the presence of a polymer surgical stent frame, and is associated with worse postprocedural hemodynamics. Procedural techniques, such as higher implantation and balloon postdilatation, may be used to help overcome problems with THV underexpansion and improve clinical outcomes.

Deformation of Transcatheter Aortic Valve Prostheses: Implications for Hypoattenuating Leaflet Thickening and Clinical Outcomes

BACKGROUND

Although transcatheter aortic valve replacement (TAVR) therapy continues to grow, there have been concerns about the occurrence of hypoattenuating leaflet thickening (HALT), which may affect prosthesis function or durability. This study aimed to examine prosthesis frame factors and correlate their extent to the frequency of HALT and clinical outcomes.

METHODS

We prospectively examined 565 patients with cardiac computed tomography screening for HALT at 30 days after balloon-expandable SAPIEN3 and self-expanding EVOLUT TAVR. Deformation of the TAVR prostheses, asymmetric prosthesis leaflet expansion, prosthesis sinus volumes, and commissural alignment were analyzed on the postprocedural computed tomography. For descriptive purposes, an index of prosthesis deformation was calculated, with values >1.00 representing relative midsegment underexpansion. A time-to-event model was performed to evaluate the association of HALT with the clinical outcome.

RESULTS

Overall, HALT was present in 21% of SAPIEN3 patients and in 16% of EVOLUT patients at 30 days after TAVR. The occurrence of HALT was directly associated with greater prosthesis frame deformation (P<0.001), worse asymmetry of the leaflets (P<0.001), and smaller TAVR neosinus volumes (P<0.001). These relations were present in both prosthetic types and in all of their size ranges (all P<0.05). In multivariable analyses that include clinical variables previously associated with HALT (eg, anticoagulant therapy), variables of TAVR prosthesis deformation remained predictive of HALT. Although HALT was not associated with changes in prosthetic hemodynamics, its presence was associated with the risk of mortality at 1 year, with respect to greater incidences of all-cause mortality (hazard ratio, 2.98 [95% CI, 1.57-5.63]; P=0.001), cardiac death (hazard ratio, 4.58 [95% CI, 1.81-11.6]; P=0.001), and a composite outcome of all-cause mortality and heart failure hospitalization (hazard ratio, 1.94 [95% CI, 1.14-3.30]; P=0.02) with adjustment for age, sex, and comorbidities.

CONCLUSIONS

Nonuniform expansion of TAVR prostheses resulting in frame deformation, asymmetric leaflet, and smaller neosinus volume is related to occurrence of HALT in patients who undergo TAVR. These data may have implications for both prosthesis valve design and deployment techniques to improve clinical outcomes for these patients.

Association of baseline and change in global longitudinal strain by computed tomography with post-transcatheter aortic valve replacement outcomes

AIMS

Transcatheter aortic valve replacement (TAVR) procedural planning requires computed tomography angiography (CTA) which allows for the assessment of left ventricular global longitudinal strain (CTA-LVGLS). There is, however, limited data on the feasibility of CTA-LVGLS, and its prognostic value. This study sought to evaluate the incremental prognostic value of baseline CTA-LVGLS, change in CTA-LVGLS after TAVR, and their association with post-TAVR outcomes.

METHODS AND RESULTS

A total of 431 patients who underwent multiphasic gated CTA using dual-source system for TAVR planning at baseline and 1-month follow-up were included [median (interquartile range) age, 83 (77-87) years; 44% female, STS-PROM score: 3.3 (2.3-5.1)%, Echo-left ventricular ejection fraction (LVEF): 60 (55-65)%, CTA-LVGLS: -18.0 (-21.6 to -14.2)%, feasible in 97% of patients]. CTA-LVGLS was measured using dedicated feature-tracking software. Over a median follow-up of 19 (13-27) months, 99 endpoints of all-cause death or heart failure hospitalization occurred. The relative hazard of the endpoint increased as baseline CTA-LVGLS worsened with -18.2% as the threshold for higher events (P = 0.005). After adjustment for baseline characteristics, CTA-LVGLS remained associated with the endpoint [hazard ratio (HR) (95% confidence interval, CI), 1.08 (1.03-1.14); P = 0.005] and incrementally improved prognostication (C-index difference, 0.026). Although CTA-LVGLS improved after TAVR [-18.3 (-21.6 to -14.3)% vs. -18.7 (-21.9 to -15.4)%, P < 0.001], patients without CTA-LVGLS improvement had higher risk of the endpoint than those with improvement or preserved baseline global longitudinal strain [HR (95% CI), 1.92 (1.19-3.12); P = 0.008].

CONCLUSIONS

In this predominantly low-risk TAVR cohort of patients, mostly with normal LVEF, assessment of CTA-LVGLS is highly feasible improving risk stratification by providing independent and incremental prognostic value over clinical and echocardiographic characteristics.

Safety, Efficacy, and Dose Protocol of Metoprolol for Heart Rate Reduction in Pediatric Outpatients Undergoing Cardiac CT Angiography

Fundamento

Qualidade de imagem e dose de radiação são otimizadas com uma frequência cardíaca (FC) lenta e estável na realização de imagens de artérias coronárias durante a angiografia cardíaca por tomografia computadorizada (CCTA, do inglês cardiac computed tomography angiography ) A segurança, a eficácia e o protocolo para a redução da FC com medicamento betabloqueador ainda não foi bem descrita em uma população de pacientes pediátricos.

Objetivo

Oferecer um protocolo de dose de metoprolol eficiente a ser usado em pacientes pediátricos externos durante a CCTA.

Métodos

Realizamos uma revisão retrospectiva de todos os pacientes pediátricos externos que receberam o metoprolol durante a CCTA. As características demográficas e clínicas foram resumidas e a redução média em FC foi estimada utilizando-se um modelo de regressão linear multivariada. As imagens foram avaliadas em uma escala de 1 a 4 (1= ideal).

Resultados

Um total de 78 pacientes externos passaram a uma CCTA com o uso de metoprolol. A média de idade foi de 13 anos, a média de peso foi de 46 kg, e 36 pacientes (46%) eram do sexo masculino. As doses médias de metoprolol foram 1,5 (IQR 1,1; 1,8) mg/kg, e 0,4 (IQR 0,2; 0,7) mg/kg para administrações orais e intravenosas, respectivamente. O produto dose-comprimento por exame foi de 57 (IQR 30, 119) mGy*cm. A redução média da FC foi 19 (IQR 12, 26) batimentos por minuto, ou 23%. Não foram relatadas complicações ou eventos adversos.

Conclusão

O uso de metoprolol num cenário de pacientes pediátricos externos para redução da FC antes de uma CCTA é seguro e eficiente. Pode-se reproduzir um protocolo de dose de metoprolol quando for necessário atingir uma FC mais lenta, garantindo tempos de aquisição mais rápidos, imagens mais claras e redução na exposição à radiação nessa população. (Arq Bras Cardiol. 2021; 116(1):100-105)

Importance of Myocardial Fibrosis in Functional Mitral Regurgitation: From Outcomes to Decision-Making

Functional mitral regurgitation (FMR) is a common and complex valve disease, in which severity and risk stratification is still a conundrum. Although risk increases with FMR severity, it is modulated by subjacent left ventricular (LV) disease. The extent of LV remodeling and dysfunction is traditionally evaluated by echocardiography, but a growing body of evidence shows that myocardial fibrosis (MF) assessment by cardiac magnetic resonance (CMR) may complement risk stratification and inform treatment decisions. This review summarizes the current knowledge on the comprehensive evaluation that CMR can provide for patients with FMR, in particular for the assessment of MF and its potential impact in clinical decision-making.

Functional DSCT assessment of tricuspid regurgitation: AROA reproducibility and comparison with 3D TEE

Funding Acknowledgements

Type of funding sources: None.

onbehalf

Minneapolis Heart Institute Foundation

Background

Tricuspid regurgitation (TR) assessment by echocardiography is often challenging. Functional dual-source CT (DSCT) with third-generation scanners allows accurate evaluation of leaflet anatomy and mobility.

Purpose

Investigate the reproducibility of tricuspid anatomical regurgitant orifice area (AROA) by DSCT, and its correlation with TR quantification by 3D TEE.

Methods

We evaluated patients with symptomatic TR referred for transcatheter tricuspid repair. DSCT (SOMATOM Force [Siemens, Erlangen, Germany]) and 3D TEE was performed on the same day as part of our institutional registry. DSCT scans were retrospective and ECG-gated, with a contrast protocol to enhance the right heart. The reproducibility of tricuspid AROA was assessed in 20 patients. The tricuspid AROA was compared with the TR severity (5-grade classification) and the 3D VCA by TEE (Panel 1).

Results

We included 60 patients (Table). The AROA had excellent intra and interobserver reliability (ICC 0.99 [0.97, 0.99] and 0.99 [0.96, 0.99]). We found a stepwise increase in tricuspid AROA from moderate to torrential TR (Panel 2A). Of 60 patients, 3D VCA was feasible in 39; in those, we found an excellent linear correlation of AROA and 3D VCA (Panel 2B).

Conclusions

Tricuspid AROA by DSCT was reproducible, showed a stepwise increase from moderate to massive TR and correlated with 3D VCA by TEE.

Baseline Patient Characteristics All (n = 60) Age, years 82 ± 7 BSA, m2 1.8 ± 0.2 NYHA III-IV, n(%) 42 (70) Atrial Fibrilation 55 (91) Hypertension 44 (73) Pulmonary Hypertension 34 (56) Chronic Kidney Disease 25 (44) Coronary Artery Disease 17 (28) Chronic Lung Disease 14 (23) Permanent Pacemaker 13 (21) Diabetes Mellitus 10 (17) Mitral Valve Repair (MitraClip) 9 (15) Mitral Valve Replacement 7 (12) Mitral Valve Repair 3 (5) Aortic Valve Replacement 5 (8) Values are mean ± SD and n (%). BSA = body surface area. Abstract Figure. Panels

Prosthesis-patient mismatch defined by cardiac computed tomography versus echocardiography after transcatheter aortic valve replacement

BACKGROUNDS

Evaluation of prosthesis-patient mismatch (P-PM) after transcatheter aortic valve replacement (TAVR) by transthoracic echocardiography (TTE) has provided conflicting results regarding its impact on outcomes. Whether post-TAVR computed tomography angiography (CTA) evaluation of P-PM can improve our understanding is unknown. We aimed to evaluate the inter-modality (TTE vs. CTA) agreement, inter-valve platform (balloon-expanding valve [BEV] vs. self-expandable valve [SEV]) differences in P-PM severity, and outcomes related to P-PM after TAVR.

METHODS

We analyzed patients with both CTA and TTE before and after TAVR. Indexed effective orifice area was calculated using two methods: TTE-derived left ventricular outflow tract (LVOT) area from measured diameter and post-TAVR CTA-measured area. Body size specific cut-offs for P-PM severity were used: for body mass index (BMI) ​< ​30 ​kg/m², moderate ​= ​0.66-0.85 ​cm²/m² and severe≤0.65 ​cm²/m²; for BMI ≥30 ​kg/m², moderate ​= ​0.56-0.70 ​cm²/m² and severe≤0.55 ​cm²/m².

RESULTS

A total of 447 patients were included (median age, 83 years; 54% male). The prevalence of P-PM (moderate or severe) was lower with CTA vs. TTE (3.5% vs. 19.5%, p ​< ​0.001). The prevalence of P-PM measured by TTE was more common in BEV compared to SEV (p ​= ​0.002), while CTA assessment showed no difference in P-PM incidence and severity between TAVR platforms (p ​= ​0.40). In multivariable analysis, CTA-defined but not TTE-defined P-PM was associated with mortality after TAVR (HR:3.97; 95%CI,1.55-10.2; p ​= ​0.004). Both CTA-defined and TTE-defined P-PM were associated with the composite of death and heart failure rehospitalization.

CONCLUSION

Although post-TAVR CTA substantially downgraded the prevalence of P-PM compared to TTE, it identified a subset of patients with clinically relevant P-PM which associated with outcomes.

Multimodality Assessment of Anomalous Aortic Origin of the Right Coronary Artery Presenting With Cardiac Arrest

Anomalous aortic origin of coronary artery (AAOCA) can range from benign anatomic variants to those presenting with sudden cardiac arrest. This unique case of right AAOCA demonstrates detailed anatomic findings from cardiac computed tomography and the effects of transient acute coronary ischemia by cardiac magnetic resonance. (Level of Difficulty: Advanced.)

NHLBI-Sponsored Randomized Trial of Postconditioning During Primary Percutaneous Coronary Intervention for ST-Elevation Myocardial Infarction

RATIONALE

Postconditioning at the time of primary percutaneous coronary intervention (PCI) for ST-segment-elevation myocardial infarction may reduce infarct size and improve myocardial salvage. However, clinical trials have shown inconsistent benefit.

OBJECTIVE

We performed the first National Heart, Lung, and Blood Institute-sponsored trial of postconditioning in the United States using strict enrollment criteria to optimize the early benefits of postconditioning and assess its long-term effects on left ventricular (LV) function.

METHODS AND RESULTS

We randomized 122 ST-segment-elevation myocardial infarction patients to postconditioning (4, 30 seconds PTCA [percutaneous transluminal coronary angioplasty] inflations/deflations)+PCI (n=65) versus routine PCI (n=57). All subjects had an occluded major epicardial artery (thrombolysis in myocardial infarction=0) with ischemic times between 1 and 6 hours with no evidence of preinfarction angina or collateral blood flow. Cardiac magnetic resonance imaging measured at 2 days post-PCI showed no difference between the postconditioning group and control in regards to infarct size (22.5±14.5 versus 24.0±18.5 g), myocardial salvage index (30.3±15.6% versus 31.5±23.6%), or mean LV ejection fraction. Magnetic resonance imaging at 12 months showed a significant recovery of LV ejection fraction in both groups (61.0±11.4% and 61.4±9.1%; P<0.01). Subjects randomized to postconditioning experienced more favorable remodeling over 1 year (LV end-diastolic volume =157±34 to 150±38 mL) compared with the control group (157±40 to 165±45 mL; P<0.03) and reduced microvascular obstruction ( P=0.05) on baseline magnetic resonance imaging and significantly less adverse LV remodeling compared with control subjects with microvascular obstruction ( P<0.05). No significant adverse events were associated with the postconditioning protocol and all patients but one (hemorrhagic stroke) survived through 1 year of follow-up.

CONCLUSIONS

We found no early benefit of postconditioning on infarct size, myocardial salvage index, and LV function compared with routine PCI. However, postconditioning was associated with improved LV remodeling at 1 year of follow-up, especially in subjects with microvascular obstruction.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov . Unique identifier: NCT01324453.

Coexistence of acute takotsubo syndrome and acute coronary syndrome

BACKGROUND

Takotsubo syndrome (TS) is an acute cardiac condition with presentation indistinguishable from acute coronary syndrome (ACS), and mechanism independent of epicardial coronary obstruction. Acute coronary artery plaque rupture/occlusion is not expected in TS. Nonetheless, the physiologic stress of ACS might itself trigger TS, leading to coexistence of both conditions, and diagnostic uncertainty.

METHODS

From 2011 to 2014, we encountered 137 consecutive patients with typical TS (without acute coronary plaque rupture/occlusion). During this time, among a population of 3,506 consecutive ACS patients, nine (0.3%) presented with features of both ACS and TS, that is, acute onset, troponin elevation, acute plaque rupture/occlusion, and reversible LV ballooning not corresponding to culprit coronary distribution.

RESULTS

The nine patients (seven female) with TS-ACS coexistence, average age 70 ± 13 years, presented with chest pain (n = 6), nausea/vomiting (n = 2), or cardiac arrest (n = 1), ST-elevation (n = 5), all with troponin elevation (peak 1.3 ± 1.2 ng/ml). Each had single vessel coronary disease; right coronary (n = 3), circumflex (n = 3), mid-LAD (n = 2), ramus intermedius (n = 1), with percutaneous coronary intervention in seven patients (78%). Initial ejection fraction was 26 ± 7%, with apical ballooning in eight patients and mid-LV ballooning in one patient. Each patient had LV ballooning resolution and ejection fraction normalization to 57 ± 3%, hospital survival was 89%.

CONCLUSIONS

Among patients with ACS, a subset have evidence of coexisting TS, findings which further expand the clinical profile of both conditions, raising the possibility that ACS itself may trigger TS.

Computed Tomographic Angiography-Derived Risk Factors for Vascular Complications in Percutaneous Transfemoral Transcatheter Aortic Valve Implantation

Transfemoral aortic valve implantation (TAVI) has become a viable alternative to surgical valve implantation, particularly for higher risk patients; however, vascular complications (VCs) remain a concern in transfemoral TAVI. We aimed to determine clinical and computed tomographic angiography-derived risk factors associated with Valve Academic Research Consortium (VARC)-2 criteria VCs in patients who underwent TAVI. From 2011 to 2017, 481 patients underwent percutaneous transfemoral TAVI at the Minneapolis Heart Institute and were screened for procedural and postprocedural access-related VC according to VARC-2 criteria. Clinical and clinical and computed tomographic angiography-derived data were collected to establish risk factors for VC. A total of 99 (21%) patients had VARC-2 VCs. Closure device failure (CDF) occurred in 56 of 99 (57%), minor VCs in 37 of 99 (37%), and major VCs occurred in 6 of 99 (6%). Access site-related VCs were preceded by CDF in 18 of 43 (42%) patients and the risk of major/minor VCs was 14 times greater in patients who experienced closure complications. The incidence of CDF was higher in common femoral artery (CFA) access sites with circumferential vessel wall calcification of more than 90° (p = 0.02) and when skin-surface to CFA access-site distance at an optimal access angle of 45° exceeded 80 mm (p = 0.03). In conclusion, both the degree of circumferential CFA access site calcification and distance to skin surface at an optimal access angle may improve risk stratification of access planning in patients who underwent percutaneous transfemoral TAVI.

Prospective Evaluation for Hypoattenuated Leaflet Thickening Following Transcatheter Aortic Valve Implantation

Prospective investigations for the frequency of hypoattenuated leaflet thickening (HALT) and its clinical implications in transcatheter aortic valve implantation (TAVI) patients are limited. We initiated a prospective screening program of TAVI patients for HALT beginning in July 2015. Eligible patients were evaluated with gated, contrast-enhanced multidetector computed tomography within 30 days of TAVI, and examined for HALT and clinical outcomes. During the study period, 287 patients (81 ± 8 years; 53% men) who underwent TAVI with commercially approved devices were examined. Overall, 26 patients (9.1%) had occurrence of HALT, and only one of these patients had detectable hemodynamic changes on echocardiography at diagnosis. Notably, 9 of 26 HALT patients had been receiving warfarin, however, the HALT patients more often had subtherapeutic international normalized ratio whereas using warfarin than patients without HALT on index multidetector computed tomography imaging (p = 0.01). Patients who developed HALT had lower baseline aortic gradient, valvuloarterial impedance, and peak aortic velocity, and more commonly had been treated with balloon-expandable valves (73% of all HALT cases) with a higher incidence among those who received larger prostheses. All patients with HALT were placed on anticoagulation at diagnosis, and valvular function remained unchanged at follow-up. Two patients with HALT (7.7%) experienced ischemic stroke. A statistical trend for more major adverse clinical events was present in HALT patients. In conclusion, HALT was detected in 9% of TAVI cases in this prospective observational cohort, with a greater frequency in patients with large, balloon-expandable prostheses. Prospective screening may be considered as early HALT is reversible by timely therapeutic anticoagulation.

Long-Term Marathon Running Is Associated with Low Coronary Plaque Formation in Women

INTRODUCTION

Marathon running is presumed to improve cardiovascular risk, but health benefits of high volume running are unknown. High-resolution coronary computed tomography angiography and cardiac risk factor assessment were completed in women with long-term marathon running histories to compare to sedentary women with similar risk factors.

METHODS

Women who had run at least one marathon per year for 10-25 yr underwent coronary computed tomography angiography, 12-lead ECG, blood pressure and heart rate measurement, lipid panel, and a demographic/health risk factor survey. Sedentary matched controls were derived from a contemporaneous clinical study database. CT scans were analyzed for calcified and noncalcified plaque prevalence, volume, stenosis severity, and calcium score.

RESULTS

Women marathon runners (n = 26), age 42-82 yr, with combined 1217 marathons (average 47) exhibited significantly lower coronary plaque prevalence and less calcific plaque volume. The marathon runners also had less risk factors (smoking, hypertension, and hyperlipidemia); significantly lower resting heart rate, body weight, body mass index, and triglyceride levels; and higher high-density lipoprotein cholesterol levels compared with controls (n = 28). The five women runners with coronary plaque had run marathons for more years and were on average 12 yr older (65 vs 53) than the runners without plaque.

CONCLUSION

Women marathon runners had minimal coronary artery calcium counts, lower coronary artery plaque prevalence, and less calcified plaque volume compared with sedentary women. Developing coronary artery plaque in long-term women marathon runners appears related to older age and more cardiac risk factors, although the runners with coronary artery plaque had accumulated significantly more years running marathons.

Lack of Phenotypic Differences by Cardiovascular Magnetic Resonance Imaging in MYH7 (β-Myosin Heavy Chain)- Versus MYBPC3 (Myosin-Binding Protein C)-Related Hypertrophic Cardiomyopathy

BACKGROUND

The 2 most commonly affected genes in hypertrophic cardiomyopathy (HCM) are MYH7 (β-myosin heavy chain) and MYBPC3 (β-myosin-binding protein C). Phenotypic differences between patients with mutations in these 2 genes have been inconsistent. Scarce data exist on the genotype-phenotype association as assessed by tomographic imaging using cardiac magnetic resonance imaging.

METHODS AND RESULTS

Cardiac magnetic resonance imaging was performed on 358 consecutive genotyped hypertrophic cardiomyopathy probands at 5 tertiary hypertrophic cardiomyopathy centers. Genetic testing revealed a pathogenic mutation in 159 patients (44.4%). The most common genes identified were MYH7 (n=53) and MYBPC3 (n=75); 33.1% and 47% of genopositive patients, respectively. Phenotypic characteristics by cardiac magnetic resonance imaging of these 2 groups were similar, including left ventricular volumes, mass, maximal wall thickness, morphology, left atrial volume, and mitral valve leaflet lengths (all P=non-significant). The presence of late gadolinium enhancement (65% versus 64%; P=0.99) and the proportion of total left ventricular mass (%late gadolinium enhancement; 10.4±13.2% versus 8.5±8.5%; P=0.44) were also similar.

CONCLUSIONS

This multicenter multinational study shows lack of phenotypic differences between MYH7- and MYBPC3-associated hypertrophic cardiomyopathy when assessed by cardiac magnetic resonance imaging. Postmutational mechanisms appear more relevant to thick-filament disease expression and outcome than the disease-causing variant per se.

Contemporary Natural History and Management of Nonobstructive Hypertrophic Cardiomyopathy

BACKGROUND

Left ventricular outflow tract gradients are absent in an important proportion of patients with hypertrophic cardiomyopathy (HCM). However, the natural course of this important patient subgroup remains largely unresolved.

OBJECTIVES

The authors systematically employed exercise (stress) echocardiography to define those patients without obstruction to left ventricular outflow at rest and/or under physiological exercise and to examine their natural history and clinical course to create a more robust understanding of this complex disease.

METHODS

We prospectively studied 573 consecutive HCM patients in 3 centers (44 ± 17 years; 66% male) with New York Heart Association functional class I/II symptoms at study entry, including 249 in whom left ventricular outflow tract obstruction was absent both at rest and following physiological exercise (<30 mm Hg; nonobstructive HCM) and retrospectively assembled clinical follow-up data.

RESULTS

Over a median follow-up of 6.5 years, 225 of 249 nonobstructive patients (90%) remained in classes I/II, whereas 24 (10%) developed progressive heart failure to New York Heart Association functional classes III/IV. Nonobstructive HCM patients were less likely to experience advanced limiting class III/IV symptoms than the 324 patients with outflow obstruction (1.6%/year vs. 7.4%/year rest obstruction vs. 3.2%/year provocable obstruction; p < 0.001). However, 7 nonobstructive patients (2.8%) did require heart transplantation for progression to end stage versus none of the obstructive patients. HCM-related mortality among nonobstructive patients was low (n = 8; 0.5%/year), with 5- and 10-year survival rates of 99% and 97%, respectively, which is not different from expected all-cause mortality in an age- and sex-matched U.S. population (p = 0.15).

CONCLUSIONS

HCM patients with nonobstructive disease appear to experience a relatively benign clinical course, associated with a low risk for advanced heart failure symptoms, other disease complications, and HCM-related mortality, and largely without the requirement for major treatment interventions. A small minority of nonobstructive HCM patients progress to heart transplant.

Accessory renal arteries: Prevalence in resistant hypertension and an important role in nonresponse to radiofrequency renal denervation

OBJECTIVE

The aim of this study was to understand the role of accessory renal arteries in resistant hypertension, and to establish their role in nonresponse to radiofrequency renal denervation (RDN) procedures.

BACKGROUND

Prior studies suggest a role for accessory renal arteries in hypertensive syndromes, and recent clinical trials of renal denervation report that these anomalies are highly prevalent in resistant hypertension. This study evaluated the relationships among resistant hypertension, accessory renal arteries, and the response to radiofrequency (RF) renal denervation.

METHODS

Computed Tomography Angiography (CTA) and magnetic resonance imaging (MRI) scans from 58 patients with resistant hypertension undergoing RF renal denervation (RDN) were evaluated. Results were compared with CT scans in 57 healthy, normotensive subjects undergoing screening as possible renal transplant donors. All scans were carefully studied for accessory renal arteries, and were correlated with long term blood pressure reduction.

RESULTS

Accessory renal arteries were markedly more prevalent in the hypertensive patients than normotensive renal donors (59% vs 32% respectively, p=0.004). RDN had an overall nonresponse rate of 29% (response rate 71%). Patients without accessory vessels had a borderline higher response rate to RDN than those with at least one accessory vessel (83% vs 62% respectively, p=0.076) and a higher RDN response than patients with untreated accessory arteries (83% vs 55%; p=0.040). For accessory renal arteries and nonresponse, the sensitivity was 76%, specificity 49%, with positive and negative predictive values 38% and 83% respectively.

CONCLUSIONS

Accessory renal arteries were markedly over-represented in resistant hypertensives compared with healthy controls. While not all patients with accessory arteries were nonresponders, nonresponse was related to both the presence and non-treatment of accessory arteries. Addressing accessory renal arteries in future clinical trials may improve RDN therapeutic efficacy.

Diagnostic Value of Contrast-Enhanced Multiphase Computed Tomography for Assessment of Percutaneous Pulmonary Valve Obstruction

Percutaneous pulmonary valve replacement has emerged as an alternative to operation for some patients with congenital heart disease requiring intervention. Endocarditis is increasingly described as an adverse event during follow-up [1-4]. Diagnosis is difficult because of the poor visualization of the prosthetic valve in the pulmonary position by transthoracic and transesophageal echocardiogram and by the metallic artifact that degrades the image quality of magnetic resonance imaging (MRI). Two cases of percutaneous pulmonary valve obstruction diagnosed by cardiac computed tomographic angiography are presented. These cases demonstrate the utility of cardiac computed tomography for noninvasive imaging of suspected thrombus or endocarditis in a percutaneously placed pulmonary valve.

Relation of Doppler Tissue Imaging Parameters With Heart Failure Progression in Hypertrophic Cardiomyopathy

Refractory progressive heart failure (HF) is becoming the predominant cause of mortality in nonobstructive hypertrophic cardiomyopathy (HC). To anticipate development of this important and often unpredictable clinical course, we investigated whether left ventricular diastolic dysfunction, assessed by echocardiographic Doppler parameters, could identify a subset of patients with HC without obstruction at rest who would experience progression of HF. Diastolic function parameters, assessed by Doppler tissue imaging (DTI), mitral inflow, and pulmonary venous flow were measured in 274 consecutive adult patients with HC evaluated from 2003 to 2007. DTI and other diastolic and clinical/demographic parameters were measured against the composite end point of HF/death, heart transplantation, or progression to advanced New York Heart Association functional class III/IV symptoms and sudden death (SD)/implantable defibrillator (ICD) interventions. HF end points were reached in 19 of 274 patients (7%) over a follow-up period of 4.0 ± 2.3 years. Variables significantly associated with HF outcome by univariate analysis included male gender, initial New York Heart Association class II, lower ejection fraction, and reduced septal and lateral e' mitral annular tissue velocities. Multivariable analysis showed only a reduced lateral e' mitral annular tissue velocity to be independently associated with the composite HF end points (HR 0.77; 95% CI 0.65 to 0.91; p = 0.003). In addition, estimated pulmonary arterial systolic pressure and extensive late gadolinium enhancement by magnetic resonance were also associated with HF outcome (p = 0.04 and p <0.001, respectively). No Doppler (or clinical) variable was associated with SD/appropriate ICD interventions. In conclusion, in HC without outflow obstruction at rest, diastolic dysfunction, evidenced by DTI-reduced lateral e' mitral annular tissue velocity, was associated with adverse long-term HF outcome but was unrelated to SD. This echocardiographic marker provides a potential noninvasive strategy for anticipating progressive HF in this HC patient group.

Hypertrophic Cardiomyopathy in Children, Adolescents, and Young Adults Associated With Low Cardiovascular Mortality With Contemporary Management Strategies

Background—

Youthful age has been considered the time of greatest risk for patients with hypertrophic cardiomyopathy (HCM), largely because of the possibility of sudden death. The last 2 decades have witnessed more reliable identification of at-risk patients and utilization of implantable cardioverter-defibrillators for prevention of sudden death, and other contemporary treatment options. Whether such management advances have significantly altered the considerable mortality rate for young HCM patients remains unresolved.

Methods and Results—

We studied long-term outcome in 474 consecutive HCM patients between 7 and 29 years of age presenting at 2 referral institutions. Over 7.1±5.1 years of follow-up (6.0 [3.0, 10.0]), 452 patients (95%) survived, with 95% experiencing no or mild symptoms. HCM-related death occurred in 18 patients (3%; 0.54%/y): arrhythmic sudden death (n=12), progressive heart failure and heart transplant complications (n=5), or postoperatively (n=1). In contrast, aborted life-threatening events occurred in 63 other high-risk patients (13%) with implantable cardioverter-defibrillator interventions for ventricular tachyarrhythmias (n=31), resuscitated out-of-hospital cardiac arrest (n=20), or heart transplant for advanced heart failure (n=12), 1.8%/y, 3-fold higher than HCM mortality. Five- and 10-year survival (considering only HCM deaths) was high (97% and 94%, respectively), virtually identical to that reported in middle-aged adult HCM patients (98% and 94%, P =0.23).

Conclusions—

In a large hospital-based cohort of young HCM patients, representing an age group considered at greatest risk, low mortality rates can be achieved with the application of contemporary cardiovascular treatment strategies, largely because of reliable identification of high-risk patients who benefited from implantable cardioverter-defibrillators for sudden death prevention, thereby creating the opportunity for extended longevity and good quality of life.

Clinical Profile of Patients With High-Risk Tako-Tsubo Cardiomyopathy

Although tako-tsubo cardiomyopathy (TTC) is regarded as a reversible condition with favorable outcome, a malignant clinical course evolves in some subjects. In this single-institution experience, we describe the clinical profile of patients with adverse TTC outcome. A cohort of 249 consecutive patients with TTC was interrogated for those with acute unstable presentation during the first 24 hours. Forty-seven patients (19%) experienced early complicated clinical course with cardiac arrest in 9 (ventricular fibrillation, n = 4, pulseless electrical activity, n = 3, and asystole, n = 2) or marked hypotension in 38 (systolic blood pressure ≤90 mm Hg requiring vasopressors and/or balloon pump). Of the 47 patients, Killip class III to IV heart failure was present in 30 (64%). Despite treatment, 8 patients (3%; all women) died inhospital due to respiratory failure, cardiogenic shock, or anoxic brain injury. All 8 inhospital deaths occurred among the 47 patients with unstable presentation, including 2 after cardiac arrest and 6 with marked hypotension. Post-TTC event mortality for a period of 4.7 ± 3.4 years significantly exceeded that in a matched general US population (standardized mortality ratio 1.4; 95% confidence interval 1.1 to 1.9; p = 0.005) largely due to noncardiac co-morbidities. In conclusion, contrary to widespread perception, TTC is not an entirely benign and reversible condition. Among this large cohort, a high-risk subgroup was identified with cardiac arrest or hemodynamic instability, accounting for all hospital deaths. Hospital nonsurvivors had a variety of irreversible co-morbid conditions with the potential to compromise clinical status and adversely affect short-term survival. Long-term survival after hospital discharge was also reduced compared with the general population because of noncardiac co-morbidities.

The Left Main Bifurcation Angle and Changes Throughout the Cardiac Cycle: Quantitative Implications for Left Main Bifurcation Stenting and Stents

OBJECTIVE

The objective of this study was to quantify the left main (LM) bifurcation angles and their changes throughout the cardiac cycle.

BACKGROUND

LM stenting is an accepted alternative to coronary artery bypass grafting. However, the LM bifurcation has great anatomic variability. Three-dimensional angles and their cyclic changes are important for coronary stenting.

METHODS

Patients undergoing coronary computed tomography angiography (CCTA) for chest pain were scanned and analyzed in three-dimensional views for left main-left anterior descending (LM-LAD), left main-left circumflex (LM-LCX), and left anterior descending-left circumflex (LAD-LCX) angles and their cyclic changes. Calculations and assessment of angles, angular variability, and how these angles change throughout the cardiac cycle were analyzed.

RESULTS

Forty-four patient scans were analyzed. The median end-diastolic LM-LCX angle was 130° and the LAD-LCX was 74°. Median end-systolic angle for the LM-LCX was 133°, and LAD-LCX was 69°. Large differences were found across all three absolute angles (LM-LCX, LAD-LCX, LM-LAD). Marked variability also occurred in how these angles changed throughout the cardiac cycle.

CONCLUSIONS

LM bifurcation geometry in patients shows marked absolute angle variability, as does diastolic-systolic angle movement. LM bifurcation stents should accommodate wide interpatient bifurcation angles at rest for both the LM-LAD and LM-LCX angles.

Significance of Late Gadolinium Enhancement at Right Ventricular Attachment to Ventricular Septum in Patients With Hypertrophic Cardiomyopathy

Cardiovascular magnetic resonance (CMR) with extensive late gadolinium enhancement (LGE) is a novel marker for increased risk for sudden death (SD) in patients with hypertrophic cardiomyopathy (HC). Small focal areas of LGE confined to the region of right ventricular (RV) insertion to ventricular septum (VS) have emerged as a frequent and highly visible CMR imaging pattern of uncertain significance. The aim of this study was to evaluate the prognostic significance of LGE confined to the RV insertion area in patients with HC. CMR was performed in 1,293 consecutive patients with HC from 7 HC centers, followed for 3.4 ± 1.7 years. Of 1,293 patients (47 ± 14 years), 134 (10%) had LGE present only in the anterior and/or inferior areas of the RV insertion to VS, occupying 3.7 ± 2.9% of left ventricular myocardium. Neither the presence nor extent of LGE in these isolated areas was a predictor of adverse HC-related risk, including SD (adjusted hazard ratio 0.82, 95% confidence interval 0.45 to 1.50, p = 0.53; adjusted hazard ratio 1.16/10% increase in LGE, 95% confidence interval 0.29 to 4.65, p = 0.83, respectively). Histopathology in 20 HC hearts show the insertion areas of RV attachment to be composed of a greatly expanded extracellular space characterized predominantly by interstitial-type fibrosis and interspersed disorganized myocyte patterns and architecture. In conclusion, LGE confined to the insertion areas of RV to VS was associated with low risk of adverse events (including SD). Gadolinium pooling in this region of the left ventricle does not reflect myocyte death and repair with replacement fibrosis or scarring.

Hypertrophic Cardiomyopathy in Adulthood Associated With Low Cardiovascular Mortality With Contemporary Management Strategies

BACKGROUND

Hypertrophic cardiomyopathy (HCM) has been prominently associated with adverse disease complications, including sudden death or heart failure death and a generally adverse prognosis, with annual mortality rates of up to 6%.

OBJECTIVES

This study determined whether recent advances in management strategy, including implantable cardioverter-defibrillators (ICDs), heart transplantation, or other therapeutic measures have significantly improved survival and the clinical course of adult HCM patients.

METHODS

We addressed long-term outcomes in 1,000 consecutive adult HCM patients presenting at 30 to 59 years of age (mean 45±8 years) over 7.2±5.2 years of follow-up.

RESULTS

Of 1,000 patients, 918 (92%) survived to 53±9.2 years of age (range 32 to 80 years) with 91% experiencing no or only mild symptoms at last evaluation. HCM-related death occurred in 40 patients (4% [0.53%/year]) at 50±10 years from the following events: progressive heart failure (n=17); arrhythmic sudden death (SD) (n=17); and embolic stroke (n=2). In contrast, 56 other high-risk patients (5.6%) survived life-threatening events, most commonly with ICD interventions for ventricular tachyarrhythmias (n=33) or heart transplantation for advanced heart failure (n=18 [0.79%/year]). SD occurred in patients who declined ICD recommendations, had evaluations before application of prophylactic ICDs to HCM, or were without conventional risk factors. The 5- and 10-year survival rates (confined to HCM deaths) were 98% and 94%, respectively, not different from the expected all-cause mortality in the general U.S. population (p=0.25). Multivariate independent predictors of adverse outcome were younger age at diagnosis, female sex, and increased left atrial dimension.

CONCLUSIONS

In a large longitudinally assessed adult HCM cohort, we have demonstrated that contemporary management strategies and treatment interventions, including ICDs for SD prevention, have significantly altered the clinical course, now resulting in a low disease-related mortality rate of 0.5%/year and an opportunity for extended longevity.