RESUMO
OBJECTIVES: The clinical impact of SARS-CoV-2 has varied across countries with varying cardiovascular manifestations. We review the cardiac presentations, in-hospital outcomes and development of cardiovascular complications in the initial cohort of SARS-CoV-2 positive patients at Imperial College Healthcare National Health Service Trust, UK. METHODS: We retrospectively analysed 498 COVID-19 positive adult admissions to our institute from 7 March to 7 April 2020. Patient data were collected for baseline demographics, comorbidities and in-hospital outcomes, especially relating to cardiovascular intervention. RESULTS: Mean age was 67.4±16.1 years and 62.2% (n=310) were male. 64.1% (n=319) of our cohort had underlying cardiovascular disease (CVD) with 53.4% (n=266) having hypertension. 43.2%(n=215) developed acute myocardial injury. Mortality was significantly increased in those patients with myocardial injury (47.4% vs 18.4%, p<0.001). Only four COVID-19 patients had invasive coronary angiography, two underwent percutaneous coronary intervention and one required a permanent pacemaker implantation. 7.0% (n=35) of patients had an inpatient echocardiogram. Acute myocardial injury (OR 2.39, 95% CI 1.31 to 4.40, p=0.005) and history of hypertension (OR 1.88, 95% CI 1.01 to 3.55, p=0.049) approximately doubled the odds of in-hospital mortality in patients admitted with COVID-19 after other variables had been controlled for. CONCLUSION: Hypertension, pre-existing CVD and acute myocardial injury were associated with increased in-hospital mortality in our cohort of COVID-19 patients. However, only a low number of patients required invasive cardiac intervention.
Assuntos
COVID-19/epidemiologia , Doenças Cardiovasculares/epidemiologia , Pandemias , Idoso , Comorbidade , Feminino , Mortalidade Hospitalar/tendências , Humanos , Incidência , Londres , Masculino , RNA Viral/análise , Estudos Retrospectivos , SARS-CoV-2/genética , Taxa de Sobrevida/tendênciasRESUMO
Aortic valve stenosis occurs 10-20 years earlier in patients on dialysis compared with the general population. This is likely related to the exposure of the valve to a milieu that predisposes to calcification as well as increased shear stress across the valve. Objective assessment of stenosis severity is largely made using echocardiography though accurate interpretation requires an understanding of the potential pitfalls of the technique and the influence of cardiac output upon the gradient measured across the valve. Timing of valve replacement in severe aortic stenosis is predominantly guided by exercise-induced symptoms (breathlessness, chest pain and [pre] syncope), which are often difficult to assess in the dialysis population who may have limited exercise capacity and symptoms due to renal failure and other comorbidities. Finally, treatment of aortic stenosis remains a constantly evolving area with advances in both conventional surgery and percutaneous techniques.
Assuntos
Estenose da Valva Aórtica , Falência Renal Crônica/terapia , Diálise Renal/efeitos adversos , Medição de Risco , Estenose da Valva Aórtica/diagnóstico , Estenose da Valva Aórtica/epidemiologia , Estenose da Valva Aórtica/etiologia , Ecocardiografia , Saúde Global , Humanos , IncidênciaRESUMO
BACKGROUND AND OBJECTIVES: Recent interest has focused on wait listing patients without pretreating coronary artery disease to expedite transplantation. Our practice is to offer coronary revascularization before transplantation if indicated. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Between 2006 and 2009, 657 patients (427 men, 230 women; ages, 56.5 ± 9.94 years) underwent pretransplant assessment with coronary angiography. 573 of 657 (87.2%) patients were wait listed; 247 of 573 (43.1%) patients were transplanted during the follow-up period, 30.09 ± 11.67 months. RESULTS: Patient survival for those not wait listed was poor, 83.2% and 45.7% at 1 and 3 years, respectively. In wait-listed patients, survival was 98.9% and 95.3% at 1 and 3 years, respectively. 184 of 657 (28.0%) patients were offered revascularization. Survival in patients (n = 16) declining revascularization was poor: 75% survived 1 year and 37.1% survived 3 years. Patients undergoing revascularization followed by transplantation (n = 51) had a 98.0% and 88.4% cardiac event-free survival at 1 and 3 years, respectively. Cardiac event-free survival for patients revascularized and awaiting deceased donor transplantation was similar: 94.0% and 90.0% at 1 and 3 years, respectively. CONCLUSIONS: Our data suggest pre-emptive coronary revascularization is not only associated with excellent survival rates in patients subsequently transplanted, but also in those patients waiting on dialysis for a deceased donor transplant.
Assuntos
Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Cardiopatias/prevenção & controle , Transplante de Rim , Listas de Espera , Idoso , Análise de Variância , Distribuição de Qui-Quadrado , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/mortalidade , Doença da Artéria Coronariana/terapia , Intervalo Livre de Doença , Feminino , Cardiopatias/etiologia , Cardiopatias/mortalidade , Humanos , Estimativa de Kaplan-Meier , Transplante de Rim/efeitos adversos , Transplante de Rim/mortalidade , Londres , Masculino , Pessoa de Meia-Idade , Revascularização Miocárdica , Valor Preditivo dos Testes , Cuidados Pré-Operatórios , Modelos de Riscos Proporcionais , Medição de Risco , Fatores de Risco , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento , Listas de Espera/mortalidadeRESUMO
BACKGROUND AND OBJECTIVES: Hemodialysis is associated with hemodynamic instability, acute cardiac ischemia, and the development of regional wall motion abnormalities (RWMAs). This study used serial intradialytic H(2)(15)O positron emission tomography scanning to confirm that the development of dialysis-induced RWMAs was associated with reduction in myocardial blood flow (MBF). DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Four prevalent hemodialysis patients without angiographically significant coronary artery disease had measurements of MBF during standard hemodialysis and biofeedback dialysis. All patients underwent serial measurements of MBF using positron emission tomography. Concurrent echocardiography was used to assess left ventricular function and the development of RWMAs. Hemodynamic variables were measured using continuous pulse wave analysis. RESULTS: Mean prehemodialysis MBF was within the normal range. Global MBF was acutely reduced during hemodialysis. Segmental MBF was reduced to a significantly greater extent in areas that developed RWMAs compared with those that did not. Not all regions with reduced MBF were functionally affected, but a reduction in myocardial blood flow of >30% from baseline was significantly associated with the development of RWMAs. No significant differences in hemodynamic tolerability, RWMA development, or MBF between dialysis modalities were observed. CONCLUSIONS: Hemodialysis is associated with repetitive myocardial ischemia, which, in the absence of coronary artery disease, may be due to coronary microvascular dysfunction. Stress-induced segmental left ventricular dysfunction correlates with matched reduction in MBF. Functional poststress recovery is consistent with myocardial stunning induced by hemodialysis. This process may be important in the development of heart failure in long-term hemodialysis patients.
Assuntos
Circulação Coronária , Falência Renal Crônica/terapia , Isquemia Miocárdica/diagnóstico por imagem , Isquemia Miocárdica/etiologia , Diálise Renal/efeitos adversos , Doença Aguda , Estudos Cross-Over , Ecocardiografia , Humanos , Pessoa de Meia-Idade , Radioisótopos de Oxigênio , Tomografia por Emissão de PósitronsRESUMO
A 49 year old Afro-Caribbean woman presents to A&E after a 30 minute episode of severe, burning central chest pain radiating to the throat. When she had the pain she felt cold and sweaty but is now symptom-free. Episodes of a similar but less severe pain had occurred daily for the previous 10 days, predominantly at rest but also when climbing the stairs at home. The patient has multiple risk factors for coronary disease (including type II diabetes, hypertension, and being a smoker), but the clinical presentation is not absolutely typical for coronary artery disease and the initial ECG is normal. There is also a history from the patient of an exercise stress test one week before, which she believed to be normal. The significance of these signs and symptoms, the diagnosis, and the short and long term treatment of these problems are discussed in an interactive case presentation.
Assuntos
Síndrome Coronariana Aguda/diagnóstico , Dor no Peito/etiologia , Síndrome Coronariana Aguda/terapia , Dor no Peito/diagnóstico , Feminino , Humanos , Pessoa de Meia-IdadeRESUMO
OBJECTIVES: This study was designed to test a rapid protocol of intravenous acetylcysteine for prevention of radiocontrast-induced nephropathy (RCIN). BACKGROUND: Oral acetylcysteine (NAC) may provide better prophylaxis against RCIN than intravenous (i.v.) hydration alone. Current protocols preclude prophylaxis of same-day or emergency patients owing to the need for prolonged pretreatment. METHODS: We prospectively randomized 80 patients with stable renal dysfunction undergoing cardiac catheterization/intervention to a rapid protocol of i.v. NAC (150 mg/kg in 500 ml N/saline over 30 min immediately before contrast followed by 50 mg/kg in 500 ml N/saline over 4 h, n = 41, 67 +/- 10 years, 90% men) or i.v. hydration (1 ml/kg/h N/saline for 12 h pre- and post-contrast, n = 39, 71 +/- 8.8 years, 85% men). RESULTS: Radiocontrast-induced nephropathy occurred in 2 of the 41 patients in the NAC group (5%) and in 8 of the 39 patients in the hydration group (21%; p = 0.045; relative risk: 0.28; 95% confidence interval 0.08 to 0.98). In the NAC group, mean serum creatinine fell from 1.85 +/- 0.59 to 1.77 +/- 0.73 and 1.79 +/- 0.73 mg/dl 48 h and four days post-contrast (p = 0.02 and 0.023 vs. baseline, respectively). In the hydration group, serum creatinine increased from 1.75 +/- 0.41 to 1.81 +/- 0.6 48 h and 1.80 +/- 0.50 mg/dl four days post-contrast (p = 0.99 and 0.23, respectively). NAC infusion was ceased after the bolus in three patients (7%) due to flushing, itching, or a transient rash. CONCLUSIONS: Administration of i.v. NAC should be considered in all patients at risk of RCIN before contrast exposure when time constraints preclude adequate oral prophylaxis, provided the patient is able to tolerate this degree of volume loading.
Assuntos
Acetilcisteína/administração & dosagem , Acetilcisteína/uso terapêutico , Cateterismo Cardíaco/efeitos adversos , Meios de Contraste/administração & dosagem , Meios de Contraste/efeitos adversos , Soluções para Reidratação/administração & dosagem , Soluções para Reidratação/uso terapêutico , Insuficiência Renal/induzido quimicamente , Insuficiência Renal/prevenção & controle , Cloreto de Sódio/administração & dosagem , Cloreto de Sódio/uso terapêutico , Ácidos Tri-Iodobenzoicos/administração & dosagem , Ácidos Tri-Iodobenzoicos/efeitos adversos , Idoso , Protocolos Clínicos , Creatinina/sangue , Esquema de Medicação , Quimioterapia Combinada , Feminino , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Insuficiência Renal/sangue , Fatores de TempoRESUMO
Brief myocardial ischemia/reperfusion has complex effects on the myocardium. In the short term the myocardium may be stunned with temporarily reduced contractile function, though this may also be accompanied by the modification and de novo synthesis of proteins that protect the heart against subsequent early or delayed insults. Repeated episodes of non-lethal ischemia, which are common in the clinical setting, combine all of these phenomena and may ultimately result in chronic contractile dysfunction. Nitric oxide is intimately linked to many of these alterations in cellular function and defense. This article examines data predominantly from in vivo large animal studies that relate to these ischemia-induced changes, the evidence for the proposed mechanisms behind both myocardial stunning and preconditioning while concentrating on the role of nitric oxide in these conditions.
Assuntos
Precondicionamento Isquêmico Miocárdico , Isquemia Miocárdica/fisiopatologia , Isquemia Miocárdica/terapia , Reperfusão Miocárdica , Miocárdio/patologia , Óxido Nítrico/fisiologia , Animais , Circulação Coronária/fisiologia , Humanos , Contração Miocárdica/fisiologia , Isquemia Miocárdica/prevenção & controleAssuntos
Angiografia Coronária/efeitos adversos , Necrose Tubular Aguda/induzido quimicamente , Necrose Tubular Aguda/prevenção & controle , Prevenção Primária/métodos , Compostos Radiofarmacêuticos/efeitos adversos , Meios de Contraste/efeitos adversos , Angiografia Coronária/métodos , Diagnóstico por Imagem/efeitos adversos , Diagnóstico por Imagem/métodos , Feminino , Hemodinâmica , Humanos , Testes de Função Renal , Masculino , Prognóstico , Circulação Renal/fisiologia , Medição de Risco , Fatores de Risco , Índice de Gravidade de DoençaRESUMO
BACKGROUND: Myocardial hibernation may result from repetitive episodes of transient ischaemia leading to prolonged dysfunction. Inducible nitric oxide synthase (iNOS) expression has been demonstrated in animals following brief, non-lethal ischaemia-reperfusion injury. We therefore, hypothesised that in human hibernating myocardium: 1). iNOS would be present; 2). the reaction of nitric oxide and superoxide would form the strong oxidant peroxynitrite; 3) that this process would be accompanied by the expression of cyclooxygenase-2 (Cox-2) which interacts with NOS and whose products could further affect myocardial function. METHOD AND RESULTS: In sixteen patients with coronary artery disease (CAD), left ventricular biopsies were obtained from chronically dysfunctional segments subtended by a stenotic artery (> 75 %) and shown to be viable by (18)F-fluorodeoxyglucose positron emission tomography. Comparison was made with myocardial biopsies (n = 8) from normally contracting myocardium in patients undergoing coronary surgery, from unused transplant donors and at post-mortem. Regional wall motion score improved in all patients 6 months post-revascularisation (from 2.7 +/- 0.7 to 1.5 +/- 0.5; p < 0.001), confirming hibernation. Immunocytochemistry localized reactivity to iNOS, Cox-2 and nitrotyrosine (a marker of peroxynitrite formation) to cardiomyocytes from hibernating segments. No difference in reactivity to endothelial NOS was seen between hibernating and control cardiomyocytes. CONCLUSION: Cox-2 and iNOS are co-expressed in hibernating myocardium with nitrotyrosine suggesting nitric oxide production and peroxynitrite formation. We propose that this is secondary to ischaemia-reperfusion and that the products of these enzymes may have consequences for myocardial contractile function and survival.
Assuntos
Isoenzimas/metabolismo , Miocárdio Atordoado/metabolismo , Miocárdio/enzimologia , Óxido Nítrico Sintase/metabolismo , Prostaglandina-Endoperóxido Sintases/metabolismo , Tirosina/análogos & derivados , Tirosina/análise , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Biópsia , Doença das Coronárias/enzimologia , Doença das Coronárias/metabolismo , Doença das Coronárias/patologia , Ciclo-Oxigenase 2 , Diuréticos/uso terapêutico , Ecocardiografia , Humanos , Imuno-Histoquímica/métodos , Proteínas de Membrana , Pessoa de Meia-Idade , Miocárdio Atordoado/enzimologia , Miocárdio Atordoado/patologia , Miocárdio/patologia , Óxido Nítrico Sintase Tipo IIRESUMO
UNLABELLED: The purpose of this study was to assess a 3-dimensional (3D)-only PET scanner (ECAT EXACT3D) for its use in the absolute quantification of myocardial blood flow (MBF) using H(2)(15)O. METHODS: Nine large white pigs were scanned with H(2)(15)O and C(15)O before and after partially occluding the circumflex (n = 4) or the left anterior descending (n = 5) coronary artery at rest and during hyperemia induced by intravenous dipyridamole. Radioactive microspheres labeled with either (57)Co or (46)Sc were injected during each of the H(2)(15)O scans, which allowed comparison between microsphere and PET measurements of regional MBF. PET analyses of 3D acquisition data were performed using filtered backprojection reconstruction and region-of-interest definition by factor and cluster analysis techniques and single-compartment model quantification. RESULTS: The Hanning filter applied in image reconstruction resulted in a left atrial blood volume recovery factor of 0.84 +/- 0.06. Differences between repeated measurements of recovery were small (mean, -0.8%; range, -6.6% to 3.6%). In 256 paired measurements of MBF ranging from 0.05 to 4.4 mL. g(- 1). min(-1), microsphere and PET measurements were fairly well correlated. The mean difference between the 2 methods was - 0.11 mL. g(-1). min(-1) and the limits of agreement (+2 SD) were -0.82 and 0.60 mL. g(-1). min(-1) (Bland-Altman plot). CONCLUSION: Dynamic measurements with H(2)(15)O using a 3D-only PET tomograph provide reliable and accurate measurements of absolute regional MBF over a wide flow range. The 3D acquisition technique can reduce the radiation dose to the subject while maintaining adequate counting statistics.
Assuntos
Circulação Coronária/fisiologia , Coração/diagnóstico por imagem , Imageamento Tridimensional , Tomografia Computadorizada de Emissão/métodos , Animais , Hiperemia/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/instrumentação , Microesferas , Radioisótopos de Oxigênio , Suínos , Tomografia Computadorizada de Emissão/instrumentação , ÁguaRESUMO
Along with hibernating myocardium, infarct size is a critical term in the progression of left ventricular remodelling and congestive heart failure. Both infarcted and hibernating myocardium determine changes in remote non-ischaemic tissue. This study was designed to test the accuracy of a new technique to quantify infarct size using positron emission tomography (PET) with [18F]2-fluoro-2-deoxy-D-glucose (FDG). Studies were carried out in (a) nine pigs with acute myocardial infarction (two sham-operated), produced by a 90-min occlusion of the circumflex coronary artery followed by a 4-h reperfusion, and (b) humans (six patients with ischaemic cardiomyopathy awaiting cardiac transplantation and five normal volunteers). In both animals and patients, myocardial FDG uptake was measured by PET during hyperinsulinaemic-euglycaemic clamp. Infarct size was quantified by an absolute threshold of tracer uptake obtained from the parametric (voxel-by-voxel) image of the metabolic rate of FDG. PET infarct size estimates were compared with independent ex vivo planimetric measurements of the explanted swine and patient hearts (at transplantation) after staining with triphenyltetrazolium chloride. There was good agreement between the planimetric and PET infarct size estimates both in pigs (n=9; r=0.96, v=0.94x+0.64, SEE=0.10, P<0.0001) and in humans (n=11; r=0.94, y=0.72x+2.93, SEE=0.09, P<0.0001). This study demonstrates the feasibility and accuracy of this PET method in estimating infarct size both in a model of reperfused acute myocardial infarction and in chronic ischaemic cardiomyopathy, although larger studies are needed to confirm these findings.