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1.
Front Cardiovasc Med ; 11: 1359715, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38596691

RESUMO

Background: A reduced left atrial (LA) strain correlates with the presence of atrial fibrillation (AF). Conventional atrial strain analysis uses two-dimensional (2D) imaging, which is, however, limited by atrial foreshortening and an underestimation of through-plane motion. Retrospective gated computed tomography (RGCT) produces high-fidelity three-dimensional (3D) images of the cardiac anatomy throughout the cardiac cycle that can be used for estimating 3D mechanics. Its feasibility for LA strain measurement, however, is understudied. Aim: The aim of this study is to develop and apply a novel workflow to estimate 3D LA motion and calculate the strain from RGCT imaging. The utility of global and regional strains to separate heart failure in patients with reduced ejection fraction (HFrEF) with and without AF is investigated. Methods: A cohort of 30 HFrEF patients with (n = 9) and without (n = 21) AF underwent RGCT prior to cardiac resynchronisation therapy. The temporal sparse free form deformation image registration method was optimised for LA feature tracking in RGCT images and used to estimate 3D LA endocardial motion. The area and fibre reservoir strains were calculated over the LA body. Universal atrial coordinates and a human atrial fibre atlas enabled the regional strain calculation and the fibre strain calculation along the local myofibre orientation, respectively. Results: It was found that global reservoir strains were significantly reduced in the HFrEF + AF group patients compared with the HFrEF-only group patients (area strain: 11.2 ± 4.8% vs. 25.3 ± 12.6%, P = 0.001; fibre strain: 4.5 ± 2.0% vs. 15.2 ± 8.8%, P = 0.001), with HFrEF + AF patients having a greater regional reservoir strain dyssynchrony. All regional reservoir strains were reduced in the HFrEF + AF patient group, in whom the inferior wall strains exhibited the most significant differences. The global reservoir fibre strain and LA volume + posterior wall reservoir fibre strain exceeded LA volume alone and 2D global longitudinal strain (GLS) for AF classification (area-under-the-curve: global reservoir fibre strain: 0.94 ± 0.02, LA volume + posterior wall reservoir fibre strain: 0.95 ± 0.02, LA volume: 0.89 ± 0.03, 2D GLS: 0.90 ± 0.03). Conclusion: RGCT enables 3D LA motion estimation and strain calculation that outperforms 2D strain metrics and LA enlargement for AF classification. Differences in regional LA strain could reflect regional myocardial properties such as atrial fibrosis burden.

2.
Radiol Clin North Am ; 62(3): 419-434, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38553178

RESUMO

The range of potential transcatheter solutions to valve disease is increasing, bringing treatment options to those in whom surgery confers prohibitively high risk. As the range of devices and their indications grow, so too will the demand for procedural planning. Computed tomography will continue to enable this growth through the provision of accurate device sizing and procedural risk assessment.


Assuntos
Valva Aórtica , Tomografia Computadorizada por Raios X , Humanos , Valva Aórtica/cirurgia , Tomografia Computadorizada por Raios X/métodos , Medição de Risco , Resultado do Tratamento , Tomografia Computadorizada Multidetectores/métodos
3.
Catheter Cardiovasc Interv ; 103(1): 169-185, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37994240

RESUMO

BACKGROUND: Vascular complications after percutaneous transfemoral transcatheter aortic valve implantation (TAVI) are associated with adverse clinical outcomes and remain a significant challenge. AIMS: The purpose of this review is to synthesize the existing evidence regarding the iliofemoral artery features predictive of vascular complications after TAVI on pre-procedural contrast-enhanced multidetector computed tomography (MDCT). METHODS: A systematic search was performed in Embase and Medline (Pubmed) databases. Studies of patients undergoing transfemoral TAVI with MDCT were included. Studies with only valve-in-valve TAVI, planned surgical intervention and those using fluoroscopic assessment were excluded. Data on study cohort, procedural characteristics and significant predictors of vascular complications were extracted. RESULTS: We identified 23 original studies involving 8697 patients who underwent TAVI between 2006 and 2020. Of all patients, 8514 (97.9%) underwent percutaneous transfemoral-TAVI, of which 8068 (94.8%) had contrast-enhanced MDCT. The incidence of major vascular complications was 6.7 ± 4.1% and minor vascular complications 26.1 ± 7.8%. Significant independent predictors of major and minor complications related to vessel dimensions were common femoral artery depth (>54 mm), sheath-to-iliofemoral artery diameter ratio (>0.91-1.19), sheath-to-femoral artery diameter ratio (>1.03-1.45) and sheath-to-femoral artery area ratio (>1.35). Substantial iliofemoral vessel tortuosity predicted 2-5-fold higher vascular risk. Significant iliofemoral calcification predicted 2-5-fold higher risk. The iliac morphology score was the only hybrid scoring system with predictive value. CONCLUSIONS: Independent iliofemoral predictors of access-site complications in TAVI were related to vessel size, depth, calcification and tortuosity. These should be considered when planning transfemoral TAVI and in the design of future risk prediction models.


Assuntos
Estenose da Valva Aórtica , Substituição da Valva Aórtica Transcateter , Doenças Vasculares , Humanos , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/cirurgia , Estenose da Valva Aórtica/complicações , Artéria Femoral/diagnóstico por imagem , Artéria Femoral/cirurgia , Tomografia Computadorizada por Raios X/métodos , Substituição da Valva Aórtica Transcateter/efeitos adversos , Substituição da Valva Aórtica Transcateter/métodos , Resultado do Tratamento , Doenças Vasculares/complicações
4.
Circ Cardiovasc Interv ; 17(1): e013657, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37929596

RESUMO

BACKGROUND: Myocardial bridges (MBs) are prevalent and can be associated with acute and chronic ischemic syndromes. We sought to determine the substrates for ischemia in patients with angina with nonobstructive coronary arteries and a MB in the left anterior descending artery. METHODS: Patients with angina with nonobstructive coronary arteries underwent the acquisition of intracoronary pressure and flow during rest, supine bicycle exercise, and adenosine infusion. Coronary wave intensity analysis was performed, with perfusion efficiency defined as accelerating wave energy/total wave energy (%). Epicardial endothelial dysfunction was defined as a reduction in epicardial vessel diameter ≥20% in response to intracoronary acetylcholine infusion. Patients with angina with nonobstructive coronary arteries and a MB were compared with 2 angina with nonobstructive coronary arteries groups with no MB: 1 with coronary microvascular disease (CMD: coronary flow reserve, <2.5) and 1 with normal coronary flow reserve (reference: coronary flow reserve, ≥2.5). RESULTS: Ninety-two patients were enrolled in the study (30 MB, 33 CMD, and 29 reference). Fractional flow reserve in these 3 groups was 0.86±0.05, 0.92±0.04, and 0.94±0.05; coronary flow reserve was 2.5±0.5, 2.0±0.3, and 3.2±0.6. Perfusion efficiency increased numerically during exercise in the reference group (65±9%-69±13%; P=0.063) but decreased in the CMD (68±10%-50±10%; P<0.001) and MB (66±9%-55±9%; P<0.001) groups. The reduction in perfusion efficiency had distinct causes: in CMD, this was driven by microcirculation-derived energy in early diastole, whereas in MB, this was driven by diminished accelerating wave energy, due to the upstream bridge, in early systole. Epicardial endothelial dysfunction was more common in the MB group (54% versus 29% reference and 38% CMD). Overall, 93% of patients with a MB had an identifiable ischemic substrate. CONCLUSIONS: MBs led to impaired coronary perfusion efficiency during exercise, which was due to diminished accelerating wave energy in early systole compared with the reference group. Additionally, there was a high prevalence of endothelial and microvascular dysfunction. These ischemic mechanisms may represent distinct treatment targets.


Assuntos
Doença da Artéria Coronariana , Reserva Fracionada de Fluxo Miocárdico , Angina Microvascular , Isquemia Miocárdica , Humanos , Circulação Coronária , Resultado do Tratamento , Vasos Coronários/diagnóstico por imagem , Isquemia , Microcirculação , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Isquemia Miocárdica/diagnóstico
5.
6.
Curr Probl Cardiol ; 49(1 Pt C): 102158, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37865301

RESUMO

Whereas the electrocardiogram (ECG) changes in hypokalemia are well known, they often receive less attention than the more striking features of hyperkalemia. Furthermore, there is a need for further discussion as to the subtleties of ECG changes that can aid in the differential diagnoses. This case study presents the ECG changes of a patient with severe hypokalemia due to diarrhea. It highlights how bifid T-waves in hypokalemia can be distinguished from other conditions such as coronary artery disease or pericarditis. Furthermore, it also shows the gradual reversal of ECG changes in the same patient when potassium is normalized.


Assuntos
Hiperpotassemia , Hipopotassemia , Humanos , Hipopotassemia/diagnóstico , Hipopotassemia/etiologia , Eletrocardiografia , Potássio , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/etiologia , Hiperpotassemia/diagnóstico , Hiperpotassemia/etiologia , Hiperpotassemia/terapia
7.
PLoS One ; 18(12): e0295789, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38096169

RESUMO

Accurate velocity reconstruction is essential for assessing coronary artery disease. We propose a Gaussian process method to reconstruct the velocity profile using the sparse data of the positron emission particle tracking (PEPT) in a biological environment, which allows the measurement of tracer particle velocity to infer fluid velocity fields. We investigated the influence of tracer particle quantity and detection time interval on flow reconstruction accuracy. Three models were used to represent different levels of stenosis and anatomical complexity: a narrowed straight tube, an idealized coronary bifurcation with stenosis, and patient-specific coronary arteries with a stenotic left circumflex artery. Computational fluid dynamics (CFD), particle tracking, and the Gaussian process of kriging were employed to simulate and reconstruct the pulsatile flow field. The study examined the error and uncertainty in velocity profile reconstruction after stenosis by comparing particle-derived flow velocity with the CFD solution. Using 600 particles (15 batches of 40 particles) released in the main coronary artery, the time-averaged error in velocity reconstruction ranged from 13.4% (no occlusion) to 161% (70% occlusion) in patient-specific anatomy. The error in maximum cross-sectional velocity at peak flow was consistently below 10% in all cases. PEPT and kriging tended to overestimate area-averaged velocity in higher occlusion cases but accurately predicted maximum cross-sectional velocity, particularly at peak flow. Kriging was shown to be useful to estimate the maximum velocity after the stenosis in the absence of negative near-wall velocity.


Assuntos
Estenose Coronária , Elétrons , Humanos , Constrição Patológica , Estudos Transversais , Estenose Coronária/diagnóstico por imagem , Vasos Coronários/diagnóstico por imagem , Velocidade do Fluxo Sanguíneo , Modelos Cardiovasculares
9.
Ann Med Surg (Lond) ; 85(11): 5813-5815, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37915703

RESUMO

Introduction and importance: Platypnea-orthodeoxia syndrome is defined as dyspnoea and deoxygenation when changing from a recumbent to an upright position. Post-Covid-19 sequelae can induce or exacerbate pulmonary hypertension and thereby render a previously mild and asymptomatic platypnea-orthodeoxia syndrome to manifest with new or worsening symptoms. Case presentation: The authors present the case of an 80-year-old man who following an episode of moderate-severe Covid-19 infection developed type I respiratory failure that required hospital discharge with long-term oxygen therapy. He had a background history of postural paroxysmal hypoxaemia which had previously raised the suspicion of a right-to-left shunt through either a patent foramen ovale, atrial septal defect or an intrapulmonary arteriovenous malformation. However, given the low burden of symptoms this was not explored further. Following recovery from Covid-19 infection, the patient experienced marked dyspnoea and oxygen desaturation in an upright position that was relieved by a return to a supine position. Discussion and conclusion: Persistent dyspnoea and hypoxia are common symptoms in patients who experience post-Covid-19 syndrome. However, when patients with prior moderate-to-severe Covid-19 illness present with new onset breathlessness and/or desaturation that is worsened in an upright position, platypnea-orthodeoxia syndrome should be considered.

11.
Curr Probl Cardiol ; 48(11): 101984, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37473946

RESUMO

The BRASH (bradycardia, renal failure, atrioventricular block, shock, and hyperkalaemia) syndrome is a recently recognized condition which may lead to life-threatening complications if not correctly identified and treated early. We report here the case of a 74-year-old woman with type 2 diabetes, hypertension and atrial flutter who presented to the emergency department with 2-day history of dizziness, presyncope, and bradycardia, and a junctional rhythm at 61 beat per minute on initial ECG. She was on apixaban, digoxin, prazosin, and telmisartan. Serum biochemistry revealed severe hyperkalaemia with a potassium 8.4 mmol/L, creatinine 161 mmol/L, glucose 15.3 mmol/L and an upper normal digoxin level of 1.2 mmol/L (ref. 0.6-1.2). Arterial blood pH was 7.2. Given the constellation of biochemical and clinical findings a diagnosis of BRASH syndrome was made, though her blood pressure values at presentation were rather high (180/65-179/59 mmHg). The patient was rapidly stabilised with the administration of intravenous insulin and dextrose, fluid resuscitation, and zirconium cyclosilicate (SZC), followed by haemodialysis. Following the correction of the serum potassium to 4.7 mmol/L, a further ECG performed 6 hours later, showed a restoration of sinus rhythm with a rate of 65 bpm, normalization of the QRS duration. The digoxin and telmisartan were discontinued, and the patient was commenced on a calcium channel antagonist for hypertension. Clinicians should be alerted to patients who present with either a BRASH (shock) or BRAHH (hypertensive manifestation) where timely intervention is essential to avoid life-threatening brady-and tachyarrhythmias in these patients.


Assuntos
Diabetes Mellitus Tipo 2 , Hiperpotassemia , Hipertensão , Idoso , Feminino , Humanos , Arritmias Cardíacas , Bradicardia/complicações , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Digoxina/uso terapêutico , Hiperpotassemia/tratamento farmacológico , Hiperpotassemia/etiologia , Potássio/uso terapêutico , Telmisartan/uso terapêutico
12.
Heart Rhythm ; 20(11): 1481-1488, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37453603

RESUMO

BACKGROUND: The WiSE-CRT System (EBR systems, Sunnyvale, CA) permits leadless left ventricular pacing. Currently, no intraprocedural guidance is used to target optimal electrode placement while simultaneously guiding acoustic transmitter placement in close proximity to the electrode to ensure adequate power delivery. OBJECTIVE: The purpose of this study was to assess the use of computed tomography (CT) anatomy, dynamic perfusion and mechanics, and predicted activation pattern to identify both the optimal electrode and transmitter locations. METHODS: A novel CT protocol was developed using preprocedural imaging and simulation to identify target segments (TSs) for electrode implantation, with late electrical and mechanical activation, with ≥5 mm wall thickness without perfusion defects. Modeling of the acoustic intensity from different transmitter implantation sites to the TSs was used to identify the optimal transmitter location. During implantation, TSs were overlaid on fluoroscopy to guide optimal electrode location that were evaluated by acute hemodynamic response (AHR) by measuring the maximal rate of left ventricular pressure rise with biventricular pacing. RESULTS: Ten patients underwent the implantation procedure. The transmitter could be implanted within the recommended site on the basis of preprocedural analysis in all patients. CT identified a mean of 4.8 ± 3.5 segments per patient with wall thickness < 5 mm. During electrode implantation, biventricular pacing within TSs resulted in a significant improvement in AHR vs non-TSs (25.5% ± 8.8% vs 12.9% ± 8.6%; P < .001). Pacing in CT-identified scar resulted in either failure to capture or minimal AHR improvement. The electrode was targeted to the TSs in all patients and was implanted in the TSs in 80%. CONCLUSION: Preprocedural imaging and modeling data with intraprocedural guidance can successfully guide WiSE-CRT electrode and transmitter implantation to allow optimal AHR and adequate power delivery.


Assuntos
Terapia de Ressincronização Cardíaca , Insuficiência Cardíaca , Humanos , Dispositivos de Terapia de Ressincronização Cardíaca , Insuficiência Cardíaca/terapia , Terapia de Ressincronização Cardíaca/métodos , Eletrodos , Tomografia Computadorizada por Raios X , Perfusão , Resultado do Tratamento , Ventrículos do Coração/diagnóstico por imagem
13.
Europace ; 25(6)2023 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-37314196

RESUMO

AIMS: The standard implantable cardioverter defibrillator (ICD) generator (can) is placed in the left pectoral area; however, in certain circumstances, right-sided cans may be required which may increase defibrillation threshold (DFT) due to suboptimal shock vectors. We aim to quantitatively assess whether the potential increase in DFT of right-sided can configurations may be mitigated by alternate positioning of the right ventricular (RV) shocking coil or adding coils in the superior vena cava (SVC) and coronary sinus (CS). METHODS AND RESULTS: A cohort of CT-derived torso models was used to assess DFT of ICD configurations with right-sided cans and alternate positioning of RV shock coils. Efficacy changes with additional coils in the SVC and CS were evaluated. A right-sided can with an apical RV shock coil significantly increased DFT compared to a left-sided can [19.5 (16.4, 27.1) J vs. 13.3 (11.7, 19.9) J, P < 0.001]. Septal positioning of the RV coil led to a further DFT increase when using a right-sided can [26.7 (18.1, 36.1) J vs. 19.5 (16.4, 27.1) J, P < 0.001], but not a left-sided can [12.1 (8.1, 17.6) J vs. 13.3 (11.7, 19.9) J, P = 0.099). Defibrillation threshold of a right-sided can with apical or septal coil was reduced the most by adding both SVC and CS coils [19.5 (16.4, 27.1) J vs. 6.6 (3.9, 9.9) J, P < 0.001, and 26.7 (18.1, 36.1) J vs. 12.1 (5.7, 13.5) J, P < 0.001]. CONCLUSION: Right-sided, compared to left-sided, can positioning results in a 50% increase in DFT. For right-sided cans, apical shock coil positioning produces a lower DFT than septal positions. Elevated right-sided can DFTs may be mitigated by utilizing additional coils in SVC and CS.


Assuntos
Seio Coronário , Desfibriladores Implantáveis , Humanos , Veia Cava Superior/diagnóstico por imagem , Simulação por Computador , Ventrículos do Coração
15.
J Cardiovasc Transl Res ; 16(4): 862-873, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36745287

RESUMO

Aortic stenosis is a condition which is fatal if left untreated. Novel quantitative imaging techniques which better characterise transvalvular pressure drops are being developed but require refinement and validation. A customisable and cost-effective workbench valve phantom circuit capable of replicating valve mechanics and pathology was created. The reproducibility and relationship of differing haemodynamic metrics were assessed from ground truth pressure data alongside imaging compatibility. The phantom met the requirements to capture ground truth pressure data alongside ultrasound and magnetic resonance image compatibility. The reproducibility was successfully tested. The robustness of three different pressure drop metrics was assessed: whilst the peak and net pressure drops provide a robust assessment of the stenotic burden in our phantom, the peak-to-peak pressure drop is a metric that is confounded by non-valvular factors such as wave reflection. The peak-to-peak pressure drop is a metric that should be reconsidered in clinical practice. The left panel shows manufacture of low cost, functional valves. The central section demonstrates circuit layout, representative MRI and US images alongside gross valve morphologies. The right panel shows the different pressure drop metrics that were assessed for reproducibility.


Assuntos
Estenose da Valva Aórtica , Valva Aórtica , Humanos , Reprodutibilidade dos Testes , Benchmarking , Hemodinâmica
16.
Can J Cardiol ; 39(5): 581-589, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36690327

RESUMO

BACKGROUND: Transcatheter therapies are a recognized alternative intervention in patients with severe mitral regurgitation who are at high surgical risk. The purpose of this study was to characterize patients screened for transcatheter mitral valve replacement (TMVR), establish the clinical and anatomic reasons for unsuitability, and determine clinical course and early outcomes. METHODS: International multicentre registry was conducted of consecutive patients screened for TMVR at 12 centres in Europe, the United States, and Canada between April 2015 and September 2018. Patient-level retrospective data were collected for all patients screened. RESULTS: From a total of 294 patients, 87 (30%) patients were suitable for and underwent TMVR, whereas 207 (70%) patients were unsuitable for TMVR. There was no difference in Society of Thoracic Surgeons predicted risk of mortality (6.3% ± 4.3% vs 6.7 ± 6.1%, P = 0.52) for mitral valve replacement between the groups. The most common reasons for TMVR unsuitability were mitral annular size outside therapeutic range (28%) and small predicted neo-LVOT (25%). Preprocedural multidetector computed tomographic demonstrated that patients unsuitable for TMVR had smaller predicted neo-left ventricular outflow tract (LVOT) area (318 ±192 mm2 vs 495 ± 202 mm2, P = 0.04). At 30 days, there was no difference in rates of rehospitalization (8% vs 8%, P = 0.21), stroke (1% vs 2%, P = 0.42), or mortality (4% vs 10%, P = 0.10), unadjusted for procedural risk, between unsuitable for TMVR and TMVR groups, respectively. CONCLUSIONS: Two-thirds of patients failed screening as anatomically unsuitable for TMVR. The findings of this study have important clinical implications, highlighting an unmet clinical need and provide a target for design innovation in future iterations of TMVR devices.


Assuntos
Implante de Prótese de Valva Cardíaca , Próteses Valvulares Cardíacas , Insuficiência da Valva Mitral , Obstrução do Fluxo Ventricular Externo , Humanos , Valva Mitral/diagnóstico por imagem , Valva Mitral/cirurgia , Implante de Prótese de Valva Cardíaca/métodos , Estudos Retrospectivos , Fatores de Risco , Cateterismo Cardíaco/métodos , Resultado do Tratamento , Obstrução do Fluxo Ventricular Externo/cirurgia , Sistema de Registros , Insuficiência da Valva Mitral/diagnóstico , Insuficiência da Valva Mitral/cirurgia
17.
J Cardiovasc Magn Reson ; 25(1): 5, 2023 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-36717885

RESUMO

BACKGROUND: Decisions in the management of aortic stenosis are based on the peak pressure drop, captured by Doppler echocardiography, whereas gold standard catheterization measurements assess the net pressure drop but are limited by associated risks. The relationship between these two measurements, peak and net pressure drop, is dictated by the pressure recovery along the ascending aorta which is mainly caused by turbulence energy dissipation. Currently, pressure recovery is considered to occur within the first 40-50 mm distally from the aortic valve, albeit there is inconsistency across interventionist centers on where/how to position the catheter to capture the net pressure drop. METHODS: We developed a non-invasive method to assess the pressure recovery distance based on blood flow momentum via 4D Flow cardiovascular magnetic resonance (CMR). Multi-center acquisitions included physical flow phantoms with different stenotic valve configurations to validate this method, first against reference measurements and then against turbulent energy dissipation (respectively n = 8 and n = 28 acquisitions) and to investigate the relationship between peak and net pressure drops. Finally, we explored the potential errors of cardiac catheterisation pressure recordings as a result of neglecting the pressure recovery distance in a clinical bicuspid aortic valve (BAV) cohort of n = 32 patients. RESULTS: In-vitro assessment of pressure recovery distance based on flow momentum achieved an average error of 1.8 ± 8.4 mm when compared to reference pressure sensors in the first phantom workbench. The momentum pressure recovery distance and the turbulent energy dissipation distance showed no statistical difference (mean difference of 2.8 ± 5.4 mm, R2 = 0.93) in the second phantom workbench. A linear correlation was observed between peak and net pressure drops, however, with strong dependences on the valvular morphology. Finally, in the BAV cohort the pressure recovery distance was 78.8 ± 34.3 mm from vena contracta, which is significantly longer than currently accepted in clinical practise (40-50 mm), and 37.5% of patients displayed a pressure recovery distance beyond the end of the ascending aorta. CONCLUSION: The non-invasive assessment of the distance to pressure recovery is possible by tracking momentum via 4D Flow CMR. Recovery is not always complete at the ascending aorta, and catheterised recordings will overestimate the net pressure drop in those situations. There is a need to re-evaluate the methods that characterise the haemodynamic burden caused by aortic stenosis as currently clinically accepted pressure recovery distance is an underestimation.


Assuntos
Estenose da Valva Aórtica , Doença da Válvula Aórtica Bicúspide , Humanos , Valor Preditivo dos Testes , Estenose da Valva Aórtica/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Valva Aórtica/diagnóstico por imagem , Hemodinâmica , Espectroscopia de Ressonância Magnética , Velocidade do Fluxo Sanguíneo/fisiologia
18.
Europace ; 25(2): 469-477, 2023 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-36369980

RESUMO

AIMS: Existing strategies that identify post-infarct ventricular tachycardia (VT) ablation target either employ invasive electrophysiological (EP) mapping or non-invasive modalities utilizing the electrocardiogram (ECG). Their success relies on localizing sites critical to the maintenance of the clinical arrhythmia, not always recorded on the 12-lead ECG. Targeting the clinical VT by utilizing electrograms (EGM) recordings stored in implanted devices may aid ablation planning, enhancing safety and speed and potentially reducing the need of VT induction. In this context, we aim to develop a non-invasive computational-deep learning (DL) platform to localize VT exit sites from surface ECGs and implanted device intracardiac EGMs. METHODS AND RESULTS: A library of ECGs and EGMs from simulated paced beats and representative post-infarct VTs was generated across five torso models. Traces were used to train DL algorithms to localize VT sites of earliest systolic activation; first tested on simulated data and then on a clinically induced VT to show applicability of our platform in clinical settings. Localization performance was estimated via localization errors (LEs) against known VT exit sites from simulations or clinical ablation targets. Surface ECGs successfully localized post-infarct VTs from simulated data with mean LE = 9.61 ± 2.61 mm across torsos. VT localization was successfully achieved from implanted device intracardiac EGMs with mean LE = 13.10 ± 2.36 mm. Finally, the clinically induced VT localization was in agreement with the clinical ablation volume. CONCLUSION: The proposed framework may be utilized for direct localization of post-infarct VTs from surface ECGs and/or implanted device EGMs, or in conjunction with efficient, patient-specific modelling, enhancing safety and speed of ablation planning.


Assuntos
Ablação por Cateter , Aprendizado Profundo , Taquicardia Ventricular , Humanos , Técnicas Eletrofisiológicas Cardíacas , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/etiologia , Taquicardia Ventricular/cirurgia , Eletrocardiografia/métodos , Infarto/cirurgia
19.
J Cardiovasc Comput Tomogr ; 17(1): 52-59, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36216700

RESUMO

BACKGROUND: FFRCT assesses the functional significance of lesions seen on CTCA, and may be a more efficient approach to chest pain evaluation. The FORECAST randomized trial found no significant difference in costs within the UK National Health Service, but implications for US costs are unknown. The purpose of this study was to compare costs in the FORECAST trial based on US healthcare cost weights, and to evaluate factors affecting costs. METHODS: Patients with stable chest pain were randomized either to the experimental strategy (CTCA with selective FFRCT), or to standard clinical pathways. Pre-randomization, the treating clinician declared the planned initial test. The primary outcome was nine-month cardiovascular care costs. RESULTS: Planned initial tests were CTCA in 912 patients (65%), stress testing in 393 (28%), and invasive angiography in 94 (7%). Mean US costs did not differ overall between the experimental strategy and standard care (cost difference +7% (+$324), CI -12% to +26%, p â€‹= â€‹0.49). Costs were 4% lower with the experimental strategy in the planned invasive angiography stratum (p for interaction â€‹= â€‹0.66). Baseline factors independently associated with costs were older age (+43%), male sex (+55%), diabetes (+37%), hypertension (+61%), hyperlipidemia (+94%), prior angina (+24%), and planned invasive angiography (+160%). Post-randomization cost drivers were coronary revascularization (+348%), invasive angiography (267%), and number of tests (+35%). CONCLUSIONS: Initial evaluation of chest pain using CTCA with FFRCT had similar US costs as standard care pathways. Costs were increased by baseline coronary risk factors and planned invasive angiography, and post-randomization invasive procedures and the number of tests. Registration at ClinicalTrials.gov (NCT03187639).


Assuntos
Doença da Artéria Coronariana , Reserva Fracionada de Fluxo Miocárdico , Humanos , Masculino , Angiografia Coronária/métodos , Medicina Estatal , Valor Preditivo dos Testes , Angina Pectoris/terapia , Angiografia por Tomografia Computadorizada/métodos
20.
Hypertension ; 80(2): 316-324, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35912678

RESUMO

BACKGROUND: Accurate blood pressure (BP) measurement is critical for optimal cardiovascular risk management. Age-related trajectories for cuff-measured BP accelerate faster in women compared with men, but whether cuff BP represents the intraarterial (invasive) aortic BP is unknown. This study aimed to determine the sex differences between cuff BP, invasive aortic BP, and the difference between the 2 measurements. METHODS: Upper-arm cuff BP and invasive aortic BP were measured during coronary angiography in 1615 subjects from the Invasive Blood Pressure Consortium Database. This analysis comprised 22 different cuff BP devices from 28 studies. RESULTS: Subjects were 64±11 years (range 40-89) and 32% women. For the same cuff systolic BP (SBP), invasive aortic SBP was 4.4 mm Hg higher in women compared with men. Cuff and invasive aortic SBP were higher in women compared with men, but the sex difference was more pronounced from invasive aortic SBP, was the lowest in younger ages, and the highest in older ages. Cuff diastolic blood pressure overestimated invasive diastolic blood pressure in both sexes. For cuff and invasive diastolic blood pressure separately, there were sex*age interactions in which diastolic blood pressure was higher in younger men and lower in older men, compared with women. Cuff pulse pressure underestimated invasive aortic pulse pressure in excess of 10 mm Hg for both sexes in older age. CONCLUSIONS: For the same cuff SBP, invasive aortic SBP was higher in women compared with men. How this translates to cardiovascular risk prediction needs to be determined, but women may be at higher BP-related risk than estimated by cuff measurements.


Assuntos
Doenças Cardiovasculares , Caracteres Sexuais , Feminino , Humanos , Masculino , Idoso , Pressão Sanguínea/fisiologia , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Fatores de Risco , Determinação da Pressão Arterial , Fatores de Risco de Doenças Cardíacas
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