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.

[Anatomic atrial remodeling after mitral valve surgery in permanent atrial fibrillation]. / Remodelado anatómico auricular tras la cirugía de la valvulopatía mitral con fibrilación auricular permanente.

BACKGROUND: Mitral valve pathology is frequently associated with atrial dilation and fibrillation. Mitral surgery allows immediate surgical atrial remodeling, and in those cases in which sinus rhythm is achieved, it is followed by late remodeling. The aim of this study was to investigate the process of postoperative atrial remodeling in patients with permanent atrial fibrillation who undergo mitral surgery. PATIENTS AND METHOD: In a prospective randomized trial, 50 patients with permanent atrial fibrillation and dilated left atrium, repaired surgically, were divided into two groups: group I, 25 patients with left atrial reduction and mitral surgery, and group II, 25 patients with isolated valve surgery. The characteristics of both groups were considered homogeneous in the preoperative assessment. RESULTS: After a mean follow-up of 31 months, 46% of the patients in group I versus 18% in group II regained sinus rhythm (p = 0.06). Atrial remodeling with shrinkage occurred in patients who recovered sinus rhythm, with larger changes in group II (-10.8% left atrial volume reduction in group I compared to -21.5% in group II; p < 0.05). The atrium became enlarged again in patients whose atrial fibrillation did not remit (+16.8% left atrial volume increase in group I versus +8.4% in group II; p < 0.05). CONCLUSIONS: Mitral surgery produces a postoperative decrease in atrial volume, especially when reduction techniques are used. Late left atrial remodeling was influenced by the type of atrial rhythm and postoperative surgical volume.

[Surgery ablation of atrial fibrillation with epicardial and endocardial biauricular radiofrequency: initial experience]. / Ablación quirúgica de la fibrilación auricular con radiofrecuencia biauricular epicárdico-endocárdica: experiencia inicial.

BACKGROUND: Atrial fibrillation is frequent in surgical patients with cardiac valvulopathies. Radiofrequency energy applied by means of surgical probes permits the reproduction of atriotomies described in the maze surgical procedure for the ablation of atrial fibrillation in a fast, safe and efficient way. This study presents our initial experience in treatment of chronic atrial fibrillation through radiofrequency performed in patients with surgical cardiac valvulopathies. PATIENTS AND METHOD: From June to November 2000, 10 patients, with surgical indications of valvulopathy, were intraoperatively treated through radiofrequency for its atrial fibrillation. Ablations were performed in the right auricle from the epicardium before starting extra corporeal circulation, and in the left auricle from the endocardium, while under circulation. Radiofrequency was applied through a surgical multielectrode probe. RESULTS: Eight patients (80%) presented some type of postoperative arrhythmia, with relapse of paroxysmal fibrillation in 3 patients and flutter in another one. At discharge, none of the patients presented relapse of chronic atrial fibrillation. There was no in-hospital mortality. After a mean follow-up of 3 months (range 1-6), 8 patients (80%) have recovered and maintained sinus rhythm. Only one patient has re-established echocardiographic biatrial contraction. CONCLUSIONS: Intraoperative radiofrequency has allowed us to perform the auricular lesions, in both auricles, in a simple way, with an initial effectiveness of 80%. Epicardial ablation of the right auricle was simple and safe. Although no patient presented relapse of chronic atrial fibrillation at hospital discharge, postoperative arrhythmias have continued to be the main postsurgical problem.