mRNA PGC-1α levels in blood samples reliably correlates with its myocardial expression: study in patients undergoing cardiac surgery.

OBJECTIVE: Peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) is a transcriptional coactivator that has been proposed to play a protective role in mouse models of cardiac ischemia and heart failure, suggesting that PGC-1α could be relevant as a prognostic marker. Our previous studies showed that the estimation of peripheral mRNA PGC-1α expression was feasible and that its induction correlated with the extent of myocardial necrosis and left ventricular remodeling in patients with myocardial infarction. In this study, we sought to determine if the myocardial and peripheral expressions of PGC-1α are well correlated and to analyze the variability of PGC-1α expression depending on the prevalence of some metabolic disorders. METHODS: This was a cohort of 35 consecutive stable heart failure patients with severe aortic stenosis who underwent an elective aortic valve replacement surgery. mRNA PGC-1α expression was simultaneously determined from myocardial biopsy specimens and blood samples obtained during surgery by quantitative PCR, and a correlation between samples was made using the Kappa index. Patients were divided into two groups according to the detection of baseline expression levels of PGC-1α in blood samples, and comparisons between both groups were made by chi-square test or unpaired Student's t-test as appropriate. RESULTS: Based on myocardial biopsies, we found that mRNA PGC-1α expression in blood samples showed a statistically significant correlation with myocardial expression (Kappa index 0.66, p<0.001). The presence of higher systemic PGC-1α expression was associated with a greater expression of some target genes such as silent information regulator 2 homolog-1 (x-fold expression in blood samples: 4.43±5.22 vs. 1.09±0.14, p=0.044) and better antioxidant status in these patients (concentration of Trolox: 0.40±0.05 vs. 0.34±0.65, p=0.006). CONCLUSIONS: Most patients with higher peripheral expression also had increased myocardial expression, so we conclude that the non-invasive estimation of mRNA PGC-1α expression from blood samples provides a good approach of the constitutive status of the mitochondrial protection system regulated by PGC-1α and that this could be used as prognostic indicator in cardiovascular disease.

Prognostic Value of Pulmonary Vascular Resistance by Magnetic Resonance in Systolic Heart Failure / Valor Prognóstico da Resistência Vascular Pulmonar através de Ressonância Magnética em Insuficiência Cardíaca

Abstract Background: Pulmonary hypertension is associated with poor prognosis in heart failure. However, non-invasive diagnosis is still challenging in clinical practice. Objective: We sought to assess the prognostic utility of non-invasive estimation of pulmonary vascular resistances (PVR) by cardiovascular magnetic resonance to predict adverse cardiovascular outcomes in heart failure with reduced ejection fraction (HFrEF). Methods: Prospective registry of patients with left ventricular ejection fraction (LVEF) < 40% and recently admitted for decompensated heart failure during three years. PVRwere calculated based on right ventricular ejection fraction and average velocity of the pulmonary artery estimated during cardiac magnetic resonance. Readmission for heart failure and all-cause mortality were considered as adverse events at follow-up. Results: 105 patients (average LVEF 26.0 ±7.7%, ischemic etiology 43%) were included. Patients with adverse events at long-term follow-up had higher values of PVR (6.93 ± 1.9 vs. 4.6 ± 1.7estimated Wood Units (eWu), p < 0.001). In multivariate Cox regression analysis, PVR ≥ 5 eWu(cutoff value according to ROC curve) was independently associated with increased risk of adverse events at 9 months follow-up (HR2.98; 95% CI 1.12-7.88; p < 0.03). Conclusions: In patients with HFrEF, the presence of PVR ≥ 5.0 Wu is associated with significantly worse clinical outcome at follow-up. Non-invasive estimation of PVR by cardiac magnetic resonance might be useful for risk stratification in HFrEF, irrespective of etiology, presence of late gadolinium enhancement or LVEF.

Resumo Fundamento: A hipertensão pulmonar está associada a mau prognóstico em insuficiência cardíaca. No entanto, o diagnóstico não-invasivo é desafiador na prática clínica. Objetivo: Avaliar a utilidade prognóstica da estimativa não-invasiva das resistências vasculares pulmonares (RVP) medidas através de ressonância magnética cardiovascular na previsão de desfechos cardiovasculares adversos em insuficiência cardíaca com fração de ejeção reduzida (ICFEr). Métodos: Registro prospectivo de pacientes com fração de ejeção do ventrículo esquerdo (FEVE) < 40% internados recentemente por insuficiência cardíaca descompensada, durante três anos. As RVP foram calculadas com base na fração de ejeção do ventrículo esquerdo e velocidade média do fluxo na artéria pulmonar estimada por ressonância magnética cardíaca. Durante a evolução, reinternação por insuficiência cardíaca e mortalidade por todas as causas foram consideradas eventos adversos. Resultados: Foram incluídos 105 pacientes (FEVE média de 26,0 ± 7,7%, etiologia isquêmica em 43%). Os valores de RVP nos pacientes que apresentaram eventos adversos durante o seguimento em longo prazo foram mais altos (6,93 ± 1,9 versus 4,6 ± 1,7 unidades Wood estimadas (uWe), p < 0,001). Na análise de regressão multivariada de Cox, RVP ≥ 5 eWu (valor de corte segundo a curva ROC) mostrou-se independentemente associada a um maior risco de eventos adversos aos 9 meses de seguimento (RR = 2,98; IC 95% = 1,12-7,88; p < 0,03). Conclusões: Em pacientes com ICFEr, a presença de RVP ≥ 5,0 uW está associada a uma evolução clínica significativamente pior. A estimativa não-invasiva da RVP através de ressonância magnética cardíaca pode ser útil na estratificação de risco em ICFEr, independentemente da etiologia, presença de realce tardio pelo gadolínio ou FEVE.

Gerbode-type left ventricular outflow tract to right atrial fistula complicating prosthetic aortic valve replacement identified by cardiac computed tomographic angiography.

Acquired left ventricular-right atrial communication (Gerbode-type defect) is a rare complication of infective endocarditis. Although transesophageal echocardiography remains the technique of choice for the evaluation of complications of endocarditis this case highlights the usefulness of cardiac computed tomography in this scenario, particularly in cases where assessment of coronary anatomy is required before surgery.

Etiological diagnosis of left ventricular dysfunction: computed tomography compared with coronary angiography and cardiac magnetic resonance.

INTRODUCTION AND OBJECTIVES: To evaluate the capability of multidetector computed tomography to diagnose the coronary etiology of left ventricular dysfunction compared with using invasive coronary angiography and magnetic resonance. METHODS: Forty consecutive patients with left ventricular dysfunction of uncertain etiology underwent invasive coronary angiography and contrast magnetic resonance. All patients were evaluated with multidetector computed tomography including coronary calcium presence and score, noninvasive coronary angiography, and myocardial tissue assessment. RESULTS: The sensitivity and specificity of the presence of coronary calcium to identify left ventricular dysfunction was 100% and 31%, respectively. If an Agatston calcium score of >100 is taken, specificity increases to 58% with sensitivity still 100%. Sensitivity and specificity for coronary angiography by multidetector computed tomography was 100% and 96%, respectively; for identifying necrosis in contrast acquisition it was 57% and 100%, respectively; and in late acquisition, 84% and 96%, respectively. To identify coronary ventricular dysfunction with necrosis, the sensitivity and specificity was 92% and 100%, respectively. CONCLUSIONS: Of all the diagnostic tools available in multidetector computed tomography, coronary angiography is the most accurate in determining the coronary origin of left ventricular dysfunction. A combination of coronary angiography and myocardial tissue study after contrast allows a single test to obtain similar information compared with the combination of invasive coronary angiography and contrast magnetic resonance.

Non-invasive assessment of coronary artery bypass grafts and native coronary arteries using 64-slice computed tomography: comparison with invasive coronary angiography.

INTRODUCTION AND OBJECTIVES: Although the diagnostic accuracy of CT in the non-invasive assessment of coronary arteries and grafts is known to be high, only a few studies have investigated the technique's reliability for the combined assessment of native coronary arteries, grafts, and vessels lying distal to anastomoses. The aim of this study was to evaluate the diagnostic accuracy of 64-slice CT for assessing coronary grafts and native coronary arteries. METHODS: In the study, 64-slice CT was used to evaluate 36 patients who had undergone coronary artery bypass graft surgery and had a clinical indication for angiographic graft assessment. The diagnostic accuracy of CT for identifying significant lesions in grafts and native coronary arteries was determined and compared with that of invasive coronary angiography. RESULTS: Of the 103 grafts studied (49 arterial and 54 venous), 96 (93.2%) could be visualized by angiography and 98 (95.1%) by CT. The sensitivity and specificity of CT for detecting significant lesions in grafts were 100% (30/30) and 97% (64/66), respectively, and the positive predictive value (PPV) and negative predictive value (NPV) were 94% and 100%, respectively. For non-revascularized coronary arteries (258 segments), the sensitivity, specificity, PPV and NPV were 94%, 95%, 80%, and 99%, respectively, and for distal vessels, 86%, 97%, 67%, and 99%, respectively. CONCLUSIONS: The diagnostic accuracy of 64-slice CT for evaluating both coronary grafts and native coronary arteries was high.

[Incorporation of cardiac rehabilitation programs and their characteristics in the Spanish National Health Service]. / Incorporation of cardiac rehabilitation programs and their characteristics in the Spanish National Health Service.

OBJECTIVES: To estimate the degree of incorporation of cardiac rehabilitation in the Spanish National Health Service, to describe the characteristics of the programs, and to report on the opinions of those responsible for them regarding their progress. PATIENTS AND METHOD: Cardiac rehabilitation centers were identified from different sources. A questionnaire which included items about coverage, resources, activities and services, selection of patients, and opinions was mailed to the heads of all units. RESULTS: Twelve public centers with cardiac rehabilitation programs were identified. Cardiac rehabilitation was offered to 53% of all eligible patients. All units treated patients with myocardial infarction, 64% treated those with heart failure; and 60% high risk patients. Approximately 10-19% of all patients were women. The physicians involved most frequently in programs were cardiologists; nonmedical professionals who participated most often were physiotherapists, and 64% of all units had a staff psychologist. Phase II rehabilitation was provided by all units, and phase III treatment was provided mainly by units that operated in coordination with out-patient services (45%). All units provided physical exercise training and counseling about the disease and risk factors, and 73% of them provided psychological support. The main reasons cited for providing rehabilitation were its efficacy and ability to prevent illness; and the main barriers to more widespread use were lack of resources and support. About three-fourths (73%) of all doctors interviewed thought that primary health care centers could play an important role in rehabilitation programs. CONCLUSIONS: Cardiac rehabilitation is poorly implemented in the Spanish National Health Service. The most significant differences between programs were related to the inclusion of high risk patients and with a diagnosis other than myocardial infarction, coordination with out-patient services, and provision of phase III rehabilitation.