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.

[Ablation of permanent atrial fibrillation in cardiac surgery. Short-term and mid-term results]. / Ablación de la fibrilación auricular permanente en la cirugía cardíaca. Resultados a corto y medio plazo.

INTRODUCTION: Surgical ablation of atrial fibrillation is currently a simple procedure that can be done during cardiac surgery in most patients. A number of different energy sources now available allow to easily create ablation lines in the atria. We describe our experience during the previous three years. PATIENTS AND METHOD: In 93 patients with cardiac problems treated with surgery and permanent atrial fibrillation (longer than 3 months), surgical ablation of the arrhythmia was done at the same time. Mean duration of the atrial fibrillation was 6 years (range 0.3 to 24 years). Mean (SD) preoperative size of the atrium as measured echocardiographically was 51.7 (8.8) mm (range 35 to 77 mm). RESULTS: Five patients died in the hospital (5.3% in-hospital mortality). After a mean follow-up of 10 months, 83.8% of the patients had recovered and maintained sinus rhythm, and 16.1% of the patients remained in atrial fibrillation. A permanent pacemaker was implanted in 3 of these patients. Among the 82 patients followed for more than 6 months, the prevalence of sinus rhythm was 84.1%. Echocardiographically documented contractility in both atria was observed in 50% of the patients. Major complications related to the ablation procedure occurred in 3.5% of the patients, and consisted of a perivalvular leak 2 months after surgery, a circumflex artery spasm, and an atrio-esophageal fistula. CONCLUSIONS: Surgical ablation of permanent atrial fibrillation is a simple procedure associated with low morbidity and mortality, and with recovery of sinus rhythm in most patients. The main problem with the procedure is the incidence of early postoperative arrhythmias.

[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.