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Contemporary World Health Organization data indicates that ≈39 million people are living with the human immunodeficiency virus. Of these, 24 million have been reported to have successfully accessed combination antiretroviral therapy. In 1996, the World Health Organization endorsed the widespread use of combination antiretroviral therapy, transforming human immunodeficiency virus infection from being a life-threatening disease to a chronic illness characterized by multiple comorbidities. The increased access to combination antiretroviral therapy has translated to people living with human immunodeficiency virus (PLWH) no longer having a reduced life expectancy. Although aging as a biological process increases exposure to oxidative stress and subsequent systemic inflammation, this effect is likely enhanced in PLWH as they age. This narrative review engages the intricate interplay between human immunodeficiency virus associated chronic inflammation, combination antiretroviral therapy, and cardiac and renal comorbidities development in aging PLWH. We examine the evolving demographic profile of PLWH, emphasizing the increasing prevalence of aging individuals within this population. A central focus of the review discusses the pathophysiological mechanisms that underpin the heightened susceptibility of PLWH to renal and cardiac diseases as they age.
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Envelhecimento , Comorbidade , Infecções por HIV , Humanos , Infecções por HIV/epidemiologia , Infecções por HIV/tratamento farmacológico , Nefropatias/epidemiologia , Cardiopatias/epidemiologia , IdosoRESUMO
Severe aortic valve stenosis is the most frequent valve pathology in the western world and approximately 50% of these patients have concomitant coronary artery disease (CAD). Revascularization of proximal obstructive CAD in patients undergoing surgical aortic valve replacement (SAVR) is common practice considered appropriate. However, the management of patients with CAD undergoing transcatheter aortic valve implantation (TAVI) is more controversial. Nevertheless, performing percutaneous coronary intervention (PCI) of significant ( > 70%) proximal coronary lesions is a widely adopted strategy, but robust supporting scientific evidence is missing. Some studies suggest that complex CAD with incomplete revascularization negatively impacts outcomes post-TAVI. As increasingly younger patients are undergoing TAVI, optimizing the long-term outcomes will become more important. Although PCI in TAVI patients is safe, no benefit on outcomes has been demonstrated, possibly due to an inadequate selection of prognostically important lesions for revascularization. A possible solution might be the use of coronary physiological indices, but these have their own limitations and more data is needed to support widespread adoption. In this review we provide an overview of current evidence on the outcomes after aortic valve replacement (AVR) and the evidence regarding revascularization in this population.
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Background: The presence of a chronic total occlusion (CTO) and severe left ventricular (LV) systolic dysfunction are known negative prognostic factors in patients with coronary artery disease. Several studies have examined the effect of CTO revascularization on mortality, symptoms, occurrence of myocardial infarction (MI), and cardiac function in patients with normal or reduced LV function. However, the effect of CTO revascularization on heart failure-related events in patients with LV dysfunction, such as heart failure hospitalization (HFH), the occurrence of atrial fibrillation (AF), and a worsening renal function (WRF), has not yet been evaluated. To assess the success rate and safety of CTO percutaneous coronary interventions (PCIs) in coronary patients with LV ejection fractions of ≤ 40% and evaluate the impact of successful CTO revascularization on HFH, occurrence of AF, and WRF. Methods: Prospectively, data were collected from CTO PCIs performed at three referral centers and analyzed. From a total of 1435 CTO PCIs, 132 (9.2%) patients with a left ventricular ejection fraction (LVEF) of ≤ 40% were included in this analysis. The median follow-up duration was 23.18 months (interquartile range (IQR): 11.02-46.66 months). Results: A successful CTO PCI was achieved in 109 of these patients, while the procedure was unsuccessful in 23 patients (82.5% procedural success rate). Overall, the intervention had an acceptable number of peri-procedural (or in-hospital) complications (9.1%). During the follow-up period, the rates of all-cause death, cardiovascular death, and non-fatal MI were not significantly different between the two groups. The rates of HFH were significantly lower in the successful PCI group, while WRF and AF did not differ between successful and unsuccessful PCI groups. Successful PCI and higher estimated glomerular filtration rate (eGFR) were independent predictors of a lower risk of HFH, while prior stroke and diabetes were independent predictors of a higher risk of HFH. Conclusions: In patients with reduced LV systolic function (ejection fraction, EF ≤ 40%), CTO PCI is a safe and effective procedure and successful CTO PCI is independently associated with a lower risk of HFH during follow-up. Further expansion of this cohort is necessary to confirm these results.
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OBJECTIVES: To identify angiographic predictors of aberrant left circumflex artery (LCx) by comparing left main (LM) length and bifurcation angle between patients with aberrant LCx and normal anatomy. BACKGROUND: Failure to recognize aberrant LCx during a cardiac catheterization may hamper correct diagnosis, delay intervention in acute coronary syndromes, and result in increased contrast volume, radiation exposure, and infarct size. METHODS: We retrospectively analyzed angiograms of aberrant LCx patients and normal anatomy matched controls, in three-participating centers. LM-length, bifurcation angle between the left anterior descending (LAD) and the first non-LAD branch of the LM, and procedural data were compared. RESULTS: Between 2003 and 2020, 136 patients with aberrant LCx and 135 controls were identified. More catheters (2.4 ± 0.6 vs. 2.2 ± 0.9, p = 0.009), larger contrast volumes (169 ± 94 ml vs. 129 ± 68 ml, p < 0.0005), and prolonged fluoroscopy time (652.9 ± 623.7 s vs. 393.1 ± 332.1 s, p < 0.0005), were required in the aberrant LCx-group compared with controls. Patients with aberrant LCx had a longer LM-length and a more acute bifurcation angle, both in caudal and cranial views, compared with controls (24.7 ± 8.1 vs. 10.8 ± 4.5 mm, p < 0.0005 and 26.7 ± 7.4 vs. 12 ± 5.5 mm, p < 0.0005, respectively, and 45.2° ± 12° vs. 88.8° ± 23°, p < 0.0005 and 51.9° ± 21° vs. 68.2° ± 28.3°, p < 0.0005, respectively). In ROC analysis, LM-length showed the best diagnostic accuracy for detecting aberrant LCx. In multiple logistic regression analysis, a cranially measured LM-length > 17.7 mm was associated with a 5.3 times greater probability of predicting aberrant LCx [95% CI (3.4-8.1), p < 0.0001]. CONCLUSIONS: Our study suggests that a long LM-length and an acute bifurcation angle can indicate the presence of aberrant LCx. We present a practical algorithm for its rapid identification.
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Doença da Artéria Coronariana , Malformações Vasculares , Cateterismo Cardíaco/efeitos adversos , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/terapia , Vasos Coronários/diagnóstico por imagem , Humanos , Estudos Retrospectivos , Resultado do TratamentoRESUMO
Although concomitant coronary artery disease (CAD) is frequent in patients with severe aortic stenosis (AS), hemodynamic assessment of CAD severity in patients undergoing valve replacement for severe AS is challenging. Myocardial hypertrophic remodeling interferes with coronary blood flow and may influence the values of fractional flow reserve (FFR) and nonhyperemic pressure ratios (NHPRs). The aim of the current study is to investigate the effect of the AS and its treatment on current indices used for evaluation of CAD. We will compare intracoronary hemodynamics before, immediately after, and 6 mo after aortic valve replacement (AVR) when it is expected that microvascular function has improved. Furthermore, we will compare FFR and resting full-cycle ratio (RFR) with myocardial perfusion single-photon emission-computed tomography (SPECT) as indicators of myocardial ischemia in patients with AS and CAD. One-hundred consecutive patients with AS and intermediate CAD will be prospectively included. Patients will undergo pre-AVR SPECT and intracoronary hemodynamic assessment at baseline, immediately after valve replacement [if transcatheter AVR (TAVR) is chosen], and 6 mo after AVR. The primary end point is the change in FFR 6 mo after AVR. Secondary end points include the acute change of FFR after TAVR, the diagnostic accuracy of FFR versus RFR compared with SPECT for the assessment of ischemia, changes in microvascular function as assessed by the index of microcirculatory resistance (IMR), and the effect of these changes on FFR. The present study will evaluate intracoronary hemodynamic parameters before, immediately after, and 6 mo after AVR in patients with AS and intermediate coronary stenosis. The understanding of the impact of AVR on the assessment of FFR, NHPR, and microvascular function may help guide the need for revascularization in patients with AS and CAD planned for AVR.
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Estenose da Valva Aórtica/diagnóstico por imagem , Valva Aórtica/diagnóstico por imagem , Doença da Artéria Coronariana/diagnóstico por imagem , Circulação Coronária , Hemodinâmica , Microcirculação , Imagem de Perfusão do Miocárdio , Projetos de Pesquisa , Tomografia Computadorizada de Emissão de Fóton Único , Valva Aórtica/fisiopatologia , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/complicações , Estenose da Valva Aórtica/fisiopatologia , Estenose da Valva Aórtica/cirurgia , Bélgica , Tomada de Decisão Clínica , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/fisiopatologia , Doença da Artéria Coronariana/cirurgia , Reserva Fracionada de Fluxo Miocárdico , Humanos , Valor Preditivo dos Testes , Estudos Prospectivos , Índice de Gravidade de Doença , Fatores de Tempo , Substituição da Valva Aórtica Transcateter , Resultado do TratamentoRESUMO
OBJECTIVES: The study aimed to demonstrate through instant wave-free ratio (iFR) measurements that myocardium distal to a chronic total occlusion (CTO) is ischemic, that ischemia is reversible by PCI, and that iFR assessment after PCI can be used to optimize PCI results. BACKGROUND: The greatest benefit of revascularization is found in patients with low fractional flow reserve. In patients with CTOs, iFR measurement may be more appropriate to evaluate ischemia as it does not require maximal microvascular vasodilation, which may be hampered by microvascular dysfunction. METHODS: The iFR was measured in 81 CTO patients, both pre- and post-PCI in 63 patients, and only post-PCI in the following 18 patients. A pressure wire pullback was performed post-PCI if iFR ≤0.89. RESULTS: The first 63 patients all had significant ischemia distal to the CTO with a median iFR of 0.33 [0.22; 0.44], improving significantly post-PCI to a median iFR of 0.93 [0.89;0.96] (p < .001). In the complete cohort, the median iFR post-PCI was 0.93 [0.86;0.96] but still ≤0.89 in 23 patients (30%). 12 of these patients had further PCI optimization because of a residual focal pressure gradient on pullback, after which only two had a final iFR ≤0.89. CONCLUSIONS: In CTO patients with an indication for PCI, iFR consistently demonstrated profound myocardial ischemia. Successful PCI immediately relieved ischemia in 70% of patients. In the remaining 30% of cases, a manual iFR pullback proved helpful in guiding further optimization of the PCI result.
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Estenose Coronária , Reserva Fracionada de Fluxo Miocárdico , Intervenção Coronária Percutânea , Cateterismo Cardíaco , Angiografia Coronária , Humanos , Isquemia , Intervenção Coronária Percutânea/efeitos adversos , Valor Preditivo dos Testes , Resultado do TratamentoRESUMO
BACKGROUND: The MAVIG X-ray protective drape (MXPD) has been shown to reduce operator radiation dose during percutaneous coronary interventions (PCI). Whether MXPDs are also effective in reducing operator radiation during chronic total occlusion (CTO) PCI, often with dual access, is unknown. METHODS: We performed a prospective, randomized-controlled study comparing operator radiation dose during CTO PCI (n = 60) with or without pelvic MXPDs. The primary outcomes were the difference in first operator radiation dose (µSv) and relative dose of the first operator (radiation dose normalized for dose area product) at the level of the chest in the two groups. The effectiveness of MXPD in CTO PCI was compared with non-CTO PCI using a patient-level pooled analysis with a previously published non-CTO PCI randomized study. RESULTS: The use of the MXPD was associated with a 37% reduction in operator dose (weighted median dose 26.0 (IQR 10.00-29.47) µSv in the drape group versus 41.8 (IQR 30.82-60.59) µSv in the no drape group; P < 0.001) and a 60% reduction in relative operator dose (median dose 3.5 (IQR 2.5-5.4) E/DAPx10-3 in the drape group versus 8.6 (IQR 4.2-12.5) E/DAPx10-3 in the no drape group; P=0.001). MXPD was equally effective in reducing operator dose in CTO PCI compared with non-CTO PCI (P value for interaction 0.963). CONCLUSIONS: The pelvic MAVIG X-ray protective drape significantly reduced CTO operator radiation dose. This trial is clinically registered with https://www.clinicaltrials.gov (unique identifier: NCT04285944).
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Oclusão Coronária , Exposição Ocupacional , Intervenção Coronária Percutânea , Doença Crônica , Angiografia Coronária , Oclusão Coronária/cirurgia , Humanos , Exposição Ocupacional/efeitos adversos , Intervenção Coronária Percutânea/efeitos adversos , Estudos Prospectivos , Doses de Radiação , Fatores de Risco , Resultado do Tratamento , Raios XRESUMO
BACKGROUND: The field of CTO PCI is expanding, but successful and safe percutaneous coronary intervention (PCI) of coronary chronic total occlusions (CTO) requires a substantial resource and experience investment. We aimed to assess temporal trends in strategies and outcomes of 2 dedicated programs for CTO PCI. METHODS: Between 2011 and 2020, 920 CTO PCI procedures were prospectively included at 2 referral centres in Belgium. Temporal trends were assessed, and logistic regression models were built to identify predictors of outcome. RESULTS: Despite an increase in lesion complexity (the J-CTO score increased from 1.3 in year 1 to 1.7-2.0 in years 8-9, p < 0.001), technical success improved from 70.0% to 85.6% in year 9 (p value for trend <0.001). We observed the most significant improvement starting at years 3-4 (OR 2.3 in year 4 versus year 1, p=0.018). Together with an increase in success rates and lesions complexity, there was an increase in the use of dual injections, retrograde approaches, the number of balloons and stents, and the use of microcatheters. Conversely, there was a decrease in large bore access, an increase in radial approach, and a shift towards contemporary dissection/reentry techniques. This strategy resulted in a stable major complication rate of 4.7% (p value for trend 0.33). The rate of coronary procedure-related myocardial injury was high (71.0%) and was associated with the use of more intracoronary devices. CONCLUSIONS: Three to four years after initiation of a dedicated CTO PCI program with 50 CTO PCIs per year, consistent high technical success and low complication rates are achieved using contemporary strategies.
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Oclusão Coronária , Intervenção Coronária Percutânea , Doença Crônica , Angiografia Coronária , Oclusão Coronária/cirurgia , Humanos , Estudos Prospectivos , Sistema de Registros , Fatores de Risco , Resultado do TratamentoRESUMO
We describe the fracture of a double layer of stents caused by nodular calcification. This resulted in recurrent in-stent restenosis, which was treated with Shockwave coronary intravascular lithotripsy.
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Angioplastia Coronária com Balão/instrumentação , Doença da Artéria Coronariana/terapia , Reestenose Coronária/terapia , Stents Farmacológicos , Ondas de Choque de Alta Energia/uso terapêutico , Litotripsia , Falha de Prótese , Calcificação Vascular/terapia , Idoso de 80 Anos ou mais , Angioplastia Coronária com Balão/efeitos adversos , Doença da Artéria Coronariana/diagnóstico por imagem , Reestenose Coronária/diagnóstico por imagem , Reestenose Coronária/etiologia , Feminino , Humanos , Recidiva , Resultado do Tratamento , Calcificação Vascular/diagnóstico por imagem , Calcificação Vascular/etiologiaRESUMO
BACKGROUND: The optimal therapeutic strategy for ST-segment elevation myocardial infarction (STEMI) patients found to have multi-vessel disease (MVD) is controversial but recent data support complete revascularisation (CR). Whether CR should be completed during the index admission or during a second staged admission remains unclear. Our main objective was to measure rates of major adverse cardiovascular events (MACEs) during the waiting period in STEMI patients selected for staged revascularisation (SR), in order to determine the safety of delaying CR. For completeness, we also describe 30-day and long-term outcomes in STEMI patients with MVD who underwent in-hospital CR. METHODS: A single-centre retrospective analysis of 931 STEMI patients treated by primary percutaneous coronary intervention (PCI) identified 397 patients with MVD who were haemodynamically stable and presented within 12 hours of chest pain onset. Of these, 191 underwent multi-vessel PCI: 49 during the index admission and 142 patients undergoing a strategy of SR. RESULTS: Our main finding was that waiting period MACE were 2% (three of 142) in patients allocated to SR (at a median of 31 days). In patients allocated to in-hospital CR, 30-day MACE rates were 10% (five of 49). During a median follow up of 39 months, all-cause mortality was 7.0% vs. 28.6%, and cardiac mortality was 2% vs. 8%, in patients allocated to SR or CR, respectively. CONCLUSIONS: Patients with STEMI and MVD who, based on clinical judgement, were allocated to a second admission SR strategy had very few adverse events during the waiting period and excellent long-term outcomes.
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Pacientes Internados , Sistema de Registros , Infarto do Miocárdio com Supradesnível do Segmento ST/cirurgia , Bélgica/epidemiologia , Causas de Morte/tendências , Feminino , Seguimentos , Mortalidade Hospitalar/tendências , Humanos , Masculino , Pessoa de Meia-Idade , Período Pré-Operatório , Estudos Retrospectivos , Fatores de Risco , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Taxa de Sobrevida/tendências , Fatores de TempoRESUMO
We report a case of early in-stent restenosis due to collapse of a Magmaris resorbable magnesium scaffold.
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Implantes Absorvíveis , Angioplastia Coronária com Balão/instrumentação , Reestenose Coronária/etiologia , Estenose Coronária/terapia , Magnésio , Falha de Prótese , Angioplastia Coronária com Balão/efeitos adversos , Angiografia Coronária , Reestenose Coronária/diagnóstico por imagem , Estenose Coronária/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Desenho de Prótese , Índice de Gravidade de Doença , Fatores de Tempo , Tomografia de Coerência Óptica , Resultado do TratamentoAssuntos
Curva de Aprendizado , Magnésio , Implantes Absorvíveis , Negro ou Afro-Americano , Sonhos , Humanos , Resultado do TratamentoRESUMO
INTRODUCTION: The introduction of drug-eluting coronary stents (DES) into clinical practice in 2002 represented a major milestone in the treatment of obstructive coronary artery disease. Over the years, significant advances in polymer coating and in antiproliferative agent technology have further improved the safety and clinical performance of newer-generation DES. AREAS COVERED: Development of platinum chromium (PtCr) alloys with high radial strength and high radiopacity have enabled the design of new, thin-strut, flexible, and highly trackable stent platforms, while simultaneously improving stent visibility. These advances have facilitated complex percutaneous treatment of a diverse population of patients in clinical practice. This review will provide an overview of the evolution in PtCr everolimus-eluting stents from PROMUS Element™ to SYNERGY™ to the recently introduced SYNERGY MEGATRON™. The clinical data will be summarized and put into perspective, especially focusing on the role of the SYNERGY™ and MEGATRON™ platforms in the treatment of complex coronary artery disease and high-risk patients. EXPERT OPINION: The SYNERGY™ stent demonstrates favorable clinical efficacy and safety outcome data, and whilst the clinical data on MEGATRON™ are sparse, early experience is promising. The specific overexpansion capabilities, visibility, and radial strength of the MEGATRON™ are attractive features for complex coronary interventions.
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Cromo , Doença da Artéria Coronariana , Stents Farmacológicos , Everolimo , Platina , Humanos , Doença da Artéria Coronariana/terapia , Everolimo/uso terapêutico , Everolimo/administração & dosagem , Platina/químicaRESUMO
BACKGROUND: Reliable assessment of coronary microvascular function is essential. Techniques to measure absolute coronary blood flow are promising but need validation. The objectives of this study were: first, to validate the potential of saline infusion to generate maximum hyperemia in vivo. Second, to validate absolute coronary blood flow measured with continuous coronary thermodilution at high (40-50 mL/min) infusion speeds and asses its safety. METHODS: Fourteen closed-chest sheep underwent absolute coronary blood flow measurements with increasing saline infusion speeds at different dosages under general anesthesia. An additional 7 open-chest sheep underwent these measurements with epicardial Doppler flow probes. Coronary flows were compared with reactive hyperemia after 45 s of coronary occlusion. RESULTS: Twenty milliliters per minute of saline infusion induced a significantly lower hyperemic coronary flow (140 versus 191 mL/min; P=0.0165), lower coronary flow reserve (1.82 versus 3.21; P≤0.0001), and higher coronary resistance (655 versus 422 woods units; P=0.0053) than coronary occlusion. On the other hand, 30 mL/min of saline infusion resulted in hyperemic coronary flow (196 versus 192 mL/min; P=0.8292), coronary flow reserve (2.77 versus 3.21; P=0.1107), and coronary resistance (415 versus 422 woods units; P=0.9181) that were not different from coronary occlusion. Hyperemic coronary flow was 40.7% with 5 mL/min, 40.8% with 10 mL/min, 73.1% with 20 mL/min, 102.3% with 30 mL/min, 99.0% with 40 mL/min, and 98.0% with 50 mL/min of saline infusion when compared with postocclusive hyperemic flow. There was a significant bias toward flow overestimation (Bland-Altman: bias±SD, -73.09±30.52; 95% limits of agreement, -132.9 to -13.27) with 40 to 50 mL/min of saline. Occasionally, ischemic changes resulted in ventricular fibrillation (9.5% with 50 mL/min) at higher infusion rates. CONCLUSIONS: Continuous saline infusion of 30 mL/min but not 20 mL/min induced maximal hyperemia. Absolute coronary blood flow measured with saline infusion speeds of 40 to 50 mL/min was not accurate and not safe.
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Circulação Coronária , Hiperemia , Microcirculação , Termodiluição , Animais , Hiperemia/fisiopatologia , Velocidade do Fluxo Sanguíneo , Vasos Coronários/fisiopatologia , Vasos Coronários/diagnóstico por imagem , Infusões Intravenosas , Ovinos , Solução Salina/administração & dosagem , Reprodutibilidade dos TestesRESUMO
BACKGROUND: The percutaneous treatment of calcified coronary lesions remains challenging and is associated with worse clinical outcomes. In addition, coronary artery calcification is associated with more frequent peri-procedural myocardial infarction. STUDY DESIGN AND OBJECTIVES: The ShOckwave ballooN or Atherectomy with Rotablation in calcified coronary artery lesions (SONAR) study is an investigator-initiated, prospective, randomized, international, multicenter, open label trial (NCT05208749) comparing a lesion preparation strategy with either shockwave intravascular lithotripsy (IVL) or rotational atherectomy (RA) before drug-eluting stent implantation in 170 patients with moderate to severe calcified coronary lesions. The primary endpoint is difference in the rate of peri-procedural myocardial infarction. Key secondary endpoints include rate of peri-procedural microvascular dysfunction, peri-procedural myocardial injury, descriptive study of IMR measurements in calcified lesions, technical and procedural success, interaction between OCT calcium score and primary endpoint, 30-day and 1-year major adverse clinical events. CONCLUSIONS: The SONAR trial is the first randomized controlled trial comparing the incidence of peri-procedural myocardial infarction between 2 contemporary calcium modification strategies (Shockwave IVL and RA) in patients with calcified coronary artery lesions. Furthermore, for the first time, the incidence of peri-procedural microvascular dysfunction after Shockwave IVL and RA will be evaluated and compared.
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Aterectomia Coronária , Doença da Artéria Coronariana , Stents Farmacológicos , Infarto do Miocárdio , Intervenção Coronária Percutânea , Calcificação Vascular , Humanos , Aterectomia Coronária/efeitos adversos , Estudos Prospectivos , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/cirurgia , Cálcio , Angiografia Coronária , Resultado do Tratamento , Calcificação Vascular/diagnóstico por imagem , Calcificação Vascular/terapia , Calcificação Vascular/etiologia , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/terapia , Doença da Artéria Coronariana/etiologia , Infarto do Miocárdio/etiologia , Intervenção Coronária Percutânea/efeitos adversos , AterectomiaRESUMO
We aimed to develop a large animal model of subcoronary aortic stenosis (AS) to study intracoronary and microcirculatory hemodynamics. A total of three surgical techniques inducing AS were evaluated in 12 sheep. Suturing the leaflets together around a dilator (n = 2) did not result in severe AS. Suturing of a pericardial patch with a variable opening just below the aortic valve (n = 5) created an AS which was poorly tolerated if the aortic valve area (AVA) was too small (0.38-1.02 cm2), but was feasible with an AVA of 1.2 cm2. However, standardization of aortic regurgitation (AR) with this technique is difficult. Therefore, we opted for implantation of an undersized AV-bioprosthesis with narrowing sutures on the leaflets (n = 5). Overall, five sheep survived the immediate postoperative period of which three had severe AS (one patch and two bioprostheses). The surviving sheep with severe AS developed left ventricular hypertrophy and signs of increased filling-pressures. Intracoronary assessment of physiological indices in these AS sheep pointed toward the development of functional microvascular dysfunction, with a significant increase in coronary resting flow and hyperemic coronary resistance, resulting in a significantly higher index of microvascular resistance (IMR) and lower myocardial resistance reserve (MRR). Microscopic analysis showed myocardial hypertrophy and signs of fibrosis without evidence of capillary rarefaction. In a large animal model of AS, microvascular changes are characterized by increased resting coronary flow and hyperemic coronary resistance resulting in increased IMR and decreased MRR. These physiological changes can influence the interpretation of regularly used coronary indices.NEW & NOTEWORTHY In an animal model of aortic valve stenosis (AS), coronary physiological changes are characterized by increased resting coronary flow and hyperemic coronary resistance. These changes can impact coronary indices frequently used to assess concomitant coronary artery disease (CAD). At this point, the best way to assess and treat CAD in AS remains unclear. Our data suggest that fractional flow reserve may underestimate CAD, and nonhyperemic pressure ratios may overestimate CAD severity before aortic valve replacement.
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Estenose da Valva Aórtica , Doença da Artéria Coronariana , Estenose Coronária , Reserva Fracionada de Fluxo Miocárdico , Animais , Ovinos , Microcirculação , Circulação Coronária , Hemodinâmica , Estenose da Valva Aórtica/cirurgia , Estenose Coronária/cirurgia , Estenose Coronária/diagnósticoRESUMO
BACKGROUND: Evaluation of myocardial ischemia in patients with aortic valve stenosis (AS) with concomitant coronary artery disease (CAD) and possible microvascular dysfunction (MVD) is challenging because fractional flow reserve (FFR) and resting full-cycle ratio (RFR) have not been validated in this clinical setting. OBJECTIVES: The objectives of this study in patients with AS and CAD are: 1. to describe the relationship between hyperemic and resting indices. 2. to investigate the acute and long-term effects of aortic valve replacement (AVR) on epicardial indices and microvascular function. 3. To assess the impact of these changes on clinical decision making. 4. To determine FFR/RFR ischemia cut-off points in AS. METHODS: In this prospective multicentric study, we performed serial measurements of FFR, RFR, and evaluated MVD by means of coronary flow reserve (CFR), the index of microvascular resistance (IMR) and microvascular resistance reserve (MRR) in patients with severe AS and intermediate-to-severe CAD, before and six months after AVR. Patients underwent myocardial perfusion single-photon emission computed tomography (SPECT) before AVR. RESULTS: In total, 146 coronary lesions in 116 patients were included. Before AVR, we observed high FFR/RFR discordance according to standard cut-off values: FFR-negative (>0.80)/RFR-positive (≤0.89) in 42.3% (68/137) of these lesions. Acutely after AVR, FFR decreased significantly (-0.0120 ± 0.0192, p=0.0045) while RFR remained stable (0.0140 ± 0.0673, p=0.3089). Six months after AVR, FFR decreased (-0.0279±0.0368) while RFR increased significantly (+0.0410±0.0487) (p<0.0001 for both), resulting in 21.5% (21/98) and 39.8% (39/98) of lesions crossing traditional FFR and RFR cut-off lines, respectively. LV-mass decreased significantly (153.68g ± 44.22 before vs 134.66g ± 37.26 after, p<0.0001). MVD was frequently observed at baseline (32.1% abnormal IMR; 68.6% abnormal MRR) with all microvascular parameters improving after AVR. Most accurate cut-offs to predict ischemia were FFR ≤0.83 and RFR ≤0.85 with comparable accuracy (75-80%). CONCLUSIONS: In patients with severe AS and CAD, FFR ≤0.83 and RFR ≤0.85 appear to predict myocardial ischemia more accurately. Six months after AVR, FFR decreases while RFR increases significantly, with simultaneous decrease of LV mass and improvement of microvascular function.