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Journal of the American Heart... Jun 2024Coronary microvascular function and hemodynamics may play a role in coronary circulation and myocardial remodeling in patients with aortic stenosis (AS). We aimed to...
BACKGROUND
Coronary microvascular function and hemodynamics may play a role in coronary circulation and myocardial remodeling in patients with aortic stenosis (AS). We aimed to evaluate the relationship between myocardial blood flow and myocardial function in patients with AS, no AS, and aortic valve sclerosis.
METHODS AND RESULTS
We included consecutive patients who had resting transthoracic echocardiography and clinically indicated positron emission tomography myocardial perfusion imaging to capture their left ventricular ejection fraction, global longitudinal strain (GLS), and myocardial flow reserve (MFR). The primary outcome was major adverse cardiovascular event (all-cause mortality, myocardial infarction, or late revascularization). There were 2778 patients (208 with aortic sclerosis, 39 with prosthetic aortic valve, 2406 with no AS, and 54, 49, and 22 with mild, moderate, and severe AS, respectively). Increasing AS severity was associated with impaired MFR (<0.001) and GLS (<0.001), even when perfusion was normal. Statistically significant associations were noted between MFR and GLS, MFR and left ventricular ejection fraction, and MFR and left ventricular ejection fraction reserve. After a median follow-up of 349 (interquartile range, 116-662) days, 4 (7.4%), 5 (10.2%), and 6 (27.3%) patients experienced a major adverse cardiovascular event in the mild, moderate, and severe AS groups, respectively. In a matched-control analysis, patients with mild-to-moderate AS had higher rates of impaired MFR (52.9% versus 39.9%; =0.048) and major adverse cardiovascular event (11.8% versus 3.0%; =0.002).
CONCLUSIONS
Despite lack of ischemia, as severity of AS increased, MFR decreased and GLS worsened, reflecting worse coronary microvascular health and myocardial remodeling. Positron emission tomography-derived MFR showed a significant independent correlation with left ventricular ejection fraction and GLS. Patients with prosthetic aortic valve showed a high prevalence of impaired MFR.
Topics: Humans; Aortic Valve Stenosis; Female; Male; Ventricular Remodeling; Aged; Ventricular Function, Left; Myocardial Perfusion Imaging; Fractional Flow Reserve, Myocardial; Stroke Volume; Microcirculation; Coronary Circulation; Echocardiography; Severity of Illness Index; Aged, 80 and over; Middle Aged; Retrospective Studies; Aortic Valve
PubMed: 38780160
DOI: 10.1161/JAHA.123.033447 -
Scientific Reports May 2024Preclinical in vivo evaluation is an essential step in the progression of new cardiac devices into patient use, with studies predominantly performed in the domestic...
Preclinical in vivo evaluation is an essential step in the progression of new cardiac devices into patient use, with studies predominantly performed in the domestic sheep model. A growing area of interest in cardiac device development is transcatheter mitral valve replacement (TMVR). Clinically, multimodal imaging, or computed tomography (CT) and echocardiography (echo) are used extensively to preoperatively determine mitral valve morphology prior to an intervention, but there is no description on how these modalities can be implemented to support preclinical studies. The purpose of this study is to apply clinically relevant CT and echo acquisition and assessment techniques to a large group of naive research sheep in order to analyze and report modality-related effects on mitral valve dimensional reference intervals in the sheep model. To this end, fifty-five adult domestic sheep underwent preoperative CT and echo exams and resultant images were analyzed using a landmark-based multiplanar measurement protocol and compiled into a master dataset for statistical analysis. We found moderate agreement between CT and echo-derived measurements of the mitral valve in sheep and propose the first clinically-relevant dimensional indices for the sheep's naive mitral valve which can be used to guide future studies evaluating novel TMVR devices. This study is the first of its kind in proposing a reproducible method for detailed examination of the mitral valve in the sheep model using clinically-relevant multimodal imaging. As in patients, CT and echo can reveal accurate native mitral valve dimensions in the sheep prior to preclinical TMVR studies.
Topics: Animals; Mitral Valve; Sheep; Heart Valve Prosthesis Implantation; Echocardiography; Tomography, X-Ray Computed; Multimodal Imaging; Sheep, Domestic; Cardiac Catheterization
PubMed: 38778204
DOI: 10.1038/s41598-024-62646-3 -
JACC. Case Reports Apr 2024Implantation of prosthetic heart valves may result in both early and late complications. Early complications are usually structural and can have significant hemodynamic...
Implantation of prosthetic heart valves may result in both early and late complications. Early complications are usually structural and can have significant hemodynamic consequences. In this clinical vignette, we highlight how malposition of a newly implanted aortic valve resulted in alterations of coronary perfusion pressure physiology and subsequent significant hemodynamic effects.
PubMed: 38774795
DOI: 10.1016/j.jaccas.2024.102278 -
Open Heart May 2024Patients with moderate aortic stenosis (AS) exhibit high morbidity and mortality. Limited evidence exists on the role of aortic valve replacement (AVR) in this patient...
OBJECTIVE
Patients with moderate aortic stenosis (AS) exhibit high morbidity and mortality. Limited evidence exists on the role of aortic valve replacement (AVR) in this patient population. To investigate the benefit of AVR in moderate AS on survival and left ventricular function.
METHODS
In a retrospective cohort study, patients with moderate AS between 2008 and 2016 were selected from the Cleveland Clinic echocardiography database and followed until 2018. Patients were classified as receiving AVR or managed medically (clinical surveillance). All-cause and cardiovascular mortality were assessed by survival analyses. Temporal haemodynamic and structural changes were assessed with longitudinal analyses using linear mixed effects models.
RESULTS
We included 1421 patients (mean age, 75.3±5.4 years and 39.9% women) followed over a median duration of 6 years. Patients in the AVR group had lower risk of all-cause (adjusted HR (aHR)=0.51, 95% CI: 0.34 to 0.77; p=0.001) and cardiovascular mortality (aHR=0.50, 95% CI: 0.31 to 0.80; p=0.004) compared with those in the clinical surveillance group irrespective of sex, receipt of other open-heart surgeries and underlying malignancy. These findings were seen only in those with preserved left ventricular ejection fraction (LVEF) ≥50%. Further, patients in the AVR group had a significant trend towards an increase in LVEF and a decrease in right ventricular systolic pressure compared with those in the clinical surveillance group.
CONCLUSIONS
In patients with moderate AS, AVR was associated with favourable clinical outcomes and left ventricular remodelling.
Topics: Humans; Aortic Valve Stenosis; Female; Male; Retrospective Studies; Aged; Heart Valve Prosthesis Implantation; Ventricular Function, Left; Aortic Valve; Treatment Outcome; Time Factors; Severity of Illness Index; Follow-Up Studies; Risk Factors; Echocardiography; Aged, 80 and over; Survival Rate; Risk Assessment; Stroke Volume
PubMed: 38769066
DOI: 10.1136/openhrt-2024-002616 -
International Journal of Infectious... May 2024To resolve an exceptional clustering of Cutibacterium avidum prosthetic valve infective endocarditis (IE) at a single heart center.
OBJECTIVE
To resolve an exceptional clustering of Cutibacterium avidum prosthetic valve infective endocarditis (IE) at a single heart center.
METHODS
During a period of 21 months, three patients experienced C. avidum bacteremia 24-128 days after aortic valve replacement. Operative procedures and electronic prescriptions of antimicrobials were surveyed, and bacterial isolates were genome sequenced.
RESULTS
The prosthetic valves were inserted by separate surgical teams. In one case, echocardiographic confirmation of IE was not achieved until 4 months after the first positive blood culture, but the causative agents were irrefutably documented in all cases by culture, or amplification of bacterial deoxyribonucleic acid, from removed prosthetic material. Whole-genome sequencing clustered isolates to a distinctive subgroup of the species but did not suggest inter-patient transmission of isolates.
CONCLUSIONS
Despite vigorous sampling of blood and tissue, detection of C. avidum was not unconditional, neither by culture nor polymerase chain reaction test. The causative agent is likely underreported and should be meticulously searched for in culture-negative prosthetic valve endocarditis.
PubMed: 38762047
DOI: 10.1016/j.ijid.2024.107099 -
Journal of the American Heart... May 2024Anticoagulation in patients with intracranial hemorrhage (ICH) and mechanical heart valves is often held for risk of ICH expansion; however, there exists a competing...
BACKGROUND
Anticoagulation in patients with intracranial hemorrhage (ICH) and mechanical heart valves is often held for risk of ICH expansion; however, there exists a competing risk of acute ischemic stroke (AIS). Optimal timing to resume anticoagulation remains uncertain.
METHODS AND RESULTS
We retrospectively studied patients with ICH and mechanical heart valves from 2000 to 2018. The primary outcome was a composite end point of symptomatic hematoma expansion or new ICH, AIS, and intracardiac thrombus up to 30 days post-ICH. The exposure was timing of reinitiation of anticoagulation classified as early (resumed up to 7 days after ICH), late (≥7 and up to 30 days after ICH), and never if not resumed or resumed after 30 days post-ICH. We included 184 patients with ICH and mechanical heart valves (65 anticoagulated early, 100 late, 19 not resumed by day 30 post-ICH). Twelve patients had AIS, 16 new ICH, and 6 intracardiac thromboses. The mean time from ICH to anticoagulation was 12.7 days. Composite outcomes occurred in 12 patients resumed early (18.5%), 14 resumed late (14.0%), and 4 never resumed (21.1%). There was no increased hazard of the composite outcome (hazard ratio [HR], 1.1 [95% CI, 0.2-6.0]), AIS, or worsening or new ICH among patients resumed early versus late. There was no difference in the composite among patients never resumed versus resumed. Patients who never resumed anticoagulation had significantly more severe ICH (median Glasgow Coma Scale: 10.6, 13.9, and 13.9 among those who resumed never, early, and late, respectively; =0.0001), higher in-hospital mortality (56.5%, 0%, and 0%, respectively; <0.0001), and an elevated 30-day AIS risk (HR, 15.9 [95% CI, 1.9-129.7], =0.0098).
CONCLUSIONS
In this study of patients with ICH and mechanical heart valves, there was no difference in 30-day thrombotic and hemorrhagic brain-related outcomes when anticoagulation was resumed within 7 versus 7 to 30 days after ICH. Withholding anticoagulation >30 days was associated with severe baseline ICH, higher in-hospital case fatality, and elevated AIS risk.
Topics: Humans; Male; Anticoagulants; Female; Retrospective Studies; Aged; Intracranial Hemorrhages; Time Factors; Heart Valve Prosthesis; Middle Aged; Ischemic Stroke; Aged, 80 and over; Risk Factors; Drug Administration Schedule; Treatment Outcome; Risk Assessment
PubMed: 38761076
DOI: 10.1161/JAHA.123.032094 -
Journal of the American Heart... May 2024The aims of this study were to understand the incidence and outcomes of patients with cardiogenic shock (CS) due to severe aortic stenosis (AS), and the impact of... (Comparative Study)
Comparative Study
BACKGROUND
The aims of this study were to understand the incidence and outcomes of patients with cardiogenic shock (CS) due to severe aortic stenosis (AS), and the impact of conventional treatment strategies in this population.
METHODS AND RESULTS
All patients admitted to the Cleveland Clinic cardiac intensive care unit between January 1, 2010 and December 31, 2021 with CS were retrospectively identified and categorized into those with CS in the setting of severe AS versus CS without AS. The impact of various treatment strategies on mortality was further assessed. We identified 2754 patients with CS during the study period, of whom 216 patients (8%) had CS in the setting of severe AS. Medical management was associated with the highest 30-day mortality when compared with either balloon aortic valve replacement or aortic valve replacement (surgical or transcatheter aortic valve replacement) (hazard ratio, 3.69 [95% CI, 2.04-6.66]; <0.0001). Among patients who received transcatheter therapy, 30-day mortality was significantly higher in patients who received balloon aortic valvuloplasty versus transcatheter aortic valve replacement (26% versus 4%, =0.02). Both surgical and transcatheter aortic valve replacement had considerably lower mortality than medical management and balloon aortic valvuloplasty at 30 days and 1 year (<0.05 for both comparisons).
CONCLUSIONS
CS due to severe AS is associated with high in-hospital and 30-day mortality, worse compared with those with CS without AS. In suitable patients, urgent surgical aortic valvuloplasty or transcatheter aortic valve replacement is associated with favorable short- and long-term outcomes. Although balloon aortic valvuloplasty may be used to temporize patients with CS in the setting of severe AS, mortality is ≈50% if not followed by definitive aortic valve replacement within 90 days.
Topics: Humans; Shock, Cardiogenic; Aortic Valve Stenosis; Male; Female; Retrospective Studies; Aged; Transcatheter Aortic Valve Replacement; Aged, 80 and over; Severity of Illness Index; Balloon Valvuloplasty; Treatment Outcome; Heart Valve Prosthesis Implantation; Risk Factors; Time Factors; Incidence
PubMed: 38761069
DOI: 10.1161/JAHA.123.033601 -
Journal of Cardiothoracic Surgery May 2024Although well-known for their thromboresistance, bileaflet mechanical heart valves (BMHV) require lifelong anti-thrombotic therapy. This must be associated with a...
BACKGROUND
Although well-known for their thromboresistance, bileaflet mechanical heart valves (BMHV) require lifelong anti-thrombotic therapy. This must be associated with a certain level of thrombogenicity. Since both thromboresistance and thrombogenicity are explained by the blood-artificial surface or liquid-solid interactions, the aim of the present study was to explore BMHV thromboresistance from new perspectives. The wettability of BMHV pyrolytic carbon (PyC) occluders was investigated in under-liquid conditions. The submerged BMHV wettability clarifies the mechanisms involved in the thromboresistance.
METHODS
The PyC occluders of a SJM Regent™ BMHV were previously laser irradiated, to create a surface hierarchical nano-texture, featuring three nano-configurations. Additionally, four PyC occluders of standard BMHV (Carbomedics, SJM Regent, Bicarbon, On-X), were investigated. All occluders were evaluated in under-liquid configuration, with silicon oil used as the working droplet, while water, simulating blood, was used as the surrounding liquid. The under-liquid droplet-substrate wetting interactions were analyzed using contact angle goniometry.
RESULTS
All the standard occluders showed very low contact angle, reflecting a pronounced affinity for non-polar molecules. No receding of the contact line could be observed for the untreated occluders. The smallest static contact angle of around 61° could be observed for On-X valve (the only valve made of full PyC). The laser-treated occluders strongly repelled oil in underwater conditions. A drastic change in their wetting behaviour was observed depending on the surrounding fluid, displaying a hydrophobic behaviour in the presence of air (as the surrounding medium), and showing instead a hydrophilic nature, when surrounded by water.
CONCLUSIONS
BMHV "fear" water and blood. The intrinsic affinity of BMHV for nonpolar fluids can be translated into a tendency to repel polar fluids, such as water and blood. The blood-artificial surface interaction in BMHV is minimized. The contact between blood and BMHV surface is drastically reduced by polar-nonpolar Van der Waals forces. The "hydro/bloodphobia" of BMHV is intrinsically related to their chemical composition and their surface energy, thus their material: PyC indeed. Pertaining to thromboresistance, the surface roughness does not play a significant role. Instead, the thromboresistance of BMHV lies in molecular interactions. BMHV wettability can be tuned by altering the surface interface, by means of nanotechnology.
Topics: Heart Valve Prosthesis; Wettability; Humans; Thrombosis; Prosthesis Design; Materials Testing
PubMed: 38760659
DOI: 10.1186/s13019-024-02786-9 -
Trials May 2024The optimal antithrombotic strategy early after aortic valve replacement surgery with a biological valve remains controversial due to lack of high-quality evidence.... (Comparative Study)
Comparative Study
BACKGROUND
The optimal antithrombotic strategy early after aortic valve replacement surgery with a biological valve remains controversial due to lack of high-quality evidence. Either oral anticoagulants or acetylsalicylic acid should be considered for the first 3 months. Hypo-attenuated leaflet thickening on cardiac computed tomography has been associated with latent bioprosthetic valve thrombosis and may be prevented with anticoagulation. We hypothesize that anticoagulation with apixaban is superior to single antiplatelet therapy with acetylsalicylic acid in reducing hypo-attenuated leaflet thickening of bioprosthetic aortic valve prostheses.
METHODS
In this prospective, open-label, randomized trial, patients undergoing isolated aortic valve replacement surgery with rapid deployment bioprosthetic valves will be randomized. The treatment group will receive 5 mg of apixaban twice a day for the first 3 months and 100 mg of acetylsalicylic acid thereafter. The control group will be administered 100 mg of acetylsalicylic acid once a day, indefinitely. After the 3-month treatment period, a contrast-enhanced electrocardiogram-gated cardiac computed tomography will be performed to identify hypo-attenuated leaflet thickening of the bioprosthetic valve. The primary objective of the study is to assess the impact of apixaban on the prevention of hypo-attenuated leaflet thickening at 3 months. The secondary and exploratory endpoints will be clinical outcomes and safety profiles of the two strategies.
DISCUSSION
Antithrombotic therapy after aortic valve replacement is used to prevent valve thrombosis and systemic thromboembolism. Latent bioprosthetic valve thrombosis is a precursor of clinically significant prosthetic valve dysfunction or thromboembolic events. The hallmark feature of latent bioprosthetic valve thrombosis is hypo-attenuated leaflet thickening on cardiac computed tomography. Subclinical leaflet thrombosis occurs frequently in bioprosthetic aortic valves, more commonly in transcatheter than in surgical valves. There is no evidence on the effect of direct oral anticoagulants on the incidence of hypo-attenuated leaflet thickening after surgical aortic valve replacement with rapid deployment bioprostheses.
TRIAL REGISTRATION
ClinicalTrials.gov NCT06184113. Registered on December 28, 2023.
Topics: Adult; Aged; Female; Humans; Male; Middle Aged; Aortic Valve; Aspirin; Bioprosthesis; Factor Xa Inhibitors; Fibrinolytic Agents; Heart Valve Prosthesis; Heart Valve Prosthesis Implantation; Platelet Aggregation Inhibitors; Prospective Studies; Pyrazoles; Pyridones; Randomized Controlled Trials as Topic; Thrombosis; Time Factors; Treatment Outcome
PubMed: 38755709
DOI: 10.1186/s13063-024-08175-w -
Computers in Biology and Medicine Jun 2024Severe aortic valve stenosis can lead to heart failure and aortic valve replacement (AVR) is the primary treatment. However, increasing prevalence of aortic stenosis...
Severe aortic valve stenosis can lead to heart failure and aortic valve replacement (AVR) is the primary treatment. However, increasing prevalence of aortic stenosis cases reveal limitations in current replacement options, necessitating improved prosthetic aortic valves. We investigate flow disturbances downstream of severe aortic stenosis and two bioprosthetic aortic valve (BioAV) designs using advanced energy-based analyses. Three-dimensional high-fidelity fluid-structure interaction simulations have been conducted and a dedicated and novel spectral analysis has been developed to characterise the kinetic energy (KE) carried by eddies in the wavenumber space. In addition, new field quantities, i.e. modal KE anisotropy intensity as well as normalised helicity intensity, are introduced. Spectral analysis shows kinetic energy (KE) decay variations, with the stenotic case aligning with Kolmogorov's theory, while BioAV cases differing. We explore the impact of flow helicity on KE transfer and decay in BioAVs. Probability distributions of modal KE anisotropy unveil flow asymmetries in the stenotic and one BioAV cases. Moreover, an inverse correlation between temporally averaged modal KE anisotropy and normalised instantaneous helicity intensity is noted, with the coefficient of determination varying among the valve configurations. Leaflet dynamics analysis highlights a stronger correlation between flow and biomechanical KE anisotropy in one BioAV due to higher leaflet displacement magnitude. These findings emphasise the role of valve architecture in aortic turbulence as well as its importance for BioAV performance and energy-based design enhancement.
Topics: Humans; Aortic Valve; Models, Cardiovascular; Anisotropy; Heart Valve Prosthesis; Hemodynamics; Aortic Valve Stenosis
PubMed: 38754219
DOI: 10.1016/j.compbiomed.2024.108552