Factores determinantes en la aparición de fibrilación auricular post-cirugía de revascularización miocárdica: un estudio prospectivo / Risk factors for postoperative atrial fibrillation after coronary artery bypass grafting: a prospective analysis

Background: Atrial fibrillation (AF) is a relevant complication after coronary artery bypass grafting (CABG). However there is controversy regarding possible contributing factors. Aim: To study the incidence of AF, its risk factors and its repercussion on hospital stay and charges, in patients undergoing CABG. Material and methods: We prospectively collected information from all patients undergoing CABG in our institution, including demographic, surgical and laboratory variables. Exclusion criteria were chronic AF, recent onset AF and patients who needed additional surgical procedures. The primary endpoint was the incidence of AF during the hospital stay. Secondary endpoints were hospital length of stay and hospital charges. Results: We included 250 patients aged 62±9 years (199 males) in the analysis. Incidence of AF was 22 percent (54 patients). Multivariable analysis showed that age (Odds Ratio (OR) =1.10), previous CABG (OR =9.39), previous use of ACE inhibitors (OR =3.28) and aortic clamp >57 minutes (OR =3.97) were significantly associated with an increased risk of postoperative AF. Previous use of beta-blockers was associated with risk reduction (OR =0.43). Patients who developed AF had a longer hospital stay (p <0.001) and higher hospital charges (p =0.003). Conclusion: AF is a frequent complication in patients undergoing CABG. Risk factors are age, time of aortic clamp, previous CABG and ACE inhibitors. Beta-blockers may prevent its occurrence. Furthermore, AF has a negative impact on both hospital stay and hospital charges.

Características de la insuficiencia cardíaca en pacientes con fracción de eyección preservada: Resultados del Registro Nacional de Insuficiencia Cardíaca, Grupo ICARO / Characteristics of heart failure with preserved ejection fraction: Results of the Chilean National Registry of Heart Failure, ICARO

Background: Heart failure (HF) with preserved ejection fraction (EF) is a condition of growing interest due to its high prevalence and difficult management. Aim: To evaluate the clinical profile of patients hospitalized with HF and preserved EF in Chilean hospitals. Material and Methods: Prospective registry of 15 centers. Among 649 patients hospitalized in functional class III and IV, an echocardiogram was performed to 353. Preserved EF was defined quantitatively as an EF >50%. Results: Out the 353 patients, 45% presented an EF >50%. Mean age in patients with EF >50 and ­50% was 66±13 and 67±13 years, respectively. Among patients with HF and EF >50%, the proportion of women was higher (73.7 and 36.3%, p <0.001), the proportion of patients with a history of hypertension (76.8 and 65.5%, p <0.05) and the presence of atrial fibrillation was also higher (62.3 and 47.8%, p <0.01) and a history of myocardial infarction was lower (17.1 and 29.5%, p <0.05). The diastolic diameter of the left ventricle was significantly lower in HF with preserved EF (51.0+10 and 63.5+10 mm respectively, p <0.001). No differences in the length of hospital stay and mortality were observed between HF with depressed and preserved EF. Female gender was an independent predictor for the presence of HF with preserved EF (Odds ratio: 2.62; confidence intervals: 1.1-6.1). Conclusions: HF and preserved EF is common among hospitalized patients, particularly in women and subjects with a history of hypertension and atrial fibrillation. Hospitalization length and mortality were similar in patients with either preserved or depressed EF.

Insuficiencia cardíaca en hospitales chilenos: resultados del Registro Nacional de Insuficiencia Cardíaca, Grupo ICARO / Cardiac failure in Chilean hospitals: results of the National Registry of Heart Failure, ICARO

Background: Heart failure (HF) is a major public health problem. In Chile hospitalized patients due to HF have not been characterized. Aim: To evaluate clinical profile and outcome of patients hospitalized for heart failure in Chilean hospitals. Patients and Methods: Prospective registry of 14 centers. Patients hospitalized for HF in functional class III and IV were included. Epidemiological and clinical data, functional class, type of presentation, decompensation cause, electrocardiogram, echocardiogram, treatment and evolution were registered. Results: Three hundred seventy two patients aged 69±13 years old, 59 percent men, were assessed. The main etiologies of HF were ischemic in 31.6 percent, hypertensive in 35.2 percent, valvular in 14.9 percent and idiopathic in 7.4 percent. There was a history of hypertension 69 percent, diabetes in 35 percent, myocardial infarction in 22 percent, atrial fibrillation (AF) in 28 percent. The presentation form of HF was chronic decompensated in 86 percent, acute in 12 percent, refractory in 2 percent. The causes of decompensation were non compliance with diet or medical prescriptions in 28 percent, infections in 22 percent and AF 17 percent. ECG showed AF in 36 percent and left bundle branch block in 16 percent. Echocardiography was performed in 52 percent of the patients, 69 percent had left ventricular ejection fraction <40 percent. On admission, 39 percent received angiotensin converting enzyme (ACE) inhibitors, 15 percent beta-blocker, 25 percent digoxin, 16 percent spironolactone and 53 percent furosemide. The mean hospital stay was 11±10 days and mortality was 4.5 percent. Conclusions: The elderly is the age group most commonly admitted to hospital due to HF. The main etiologies were ischemic and hypertensive. The main causes for decompensations were noncompliance with diet or medical prescriptions and infections. A significant proportion had a relatively well preserved ventricular systolic function (Rev Méd Chile 2004; 132: 655-62).