Preoperative left atrial minimum volume as a surrogate marker of postoperative symptoms in senile patients with aortic stenosis who underwent surgical aortic valve replacement

The Prognostic Significance of Atrial Fibrillation and Left Atrium Size in Patients with Aortic Stenosis

Aim    Aortic stenosis increases left atrial (LA) pressure and may lead to its remodeling. This can cause supraventricular arrhythmia. The aim of this study was to determine if the size of the LA and the presence of atrial fibrillation are related to the prognosis of patients with aortic stenosis.Material and methods    Clinical evaluation and standard transthoracic echocardiographic studies were performed in 397 patients with moderate to severe aortic stenosis.Results    In all patients, LA dimension above the median (≥43 mm) was associated with a significantly higher risk of death [HR 1.79 (CL 1.06-3.03)] and a LA volume above the median of 80 ml was associated with a significantly higher risk of death [HR 2.44 (CI 1.12-5.33)]. The presence of atrial fibrillation was significantly associated with a higher risk of death (p <0.0001). The presence of atrial fibrillation [HR 1.69 (CI 1.02-2.86)], lower left ventricular ejection fraction [HR 1.23 (CI 1.04-1.45)], higher NYHA heart failure class [HR 4.15 (CI 1.40-13.20)] and renal failure [HR 2.10 (CI 1.31-3.56)] were independent risk factors of death in patients in aortic stenosis.Conclusion    The size and volume of the LA and the occurrence of atrial fibrillation are important risk factors for death in patients with aortic stenosis. The presence of renal dysfunction, low left ventricular ejection fraction, high NYHA functional class and atrial fibrillation are independent risk factors of poor prognosis in patients with aortic stenosis.

Left atrial volume index predicts future improvement of B-type natriuretic peptide levels after transcatheter aortic valve replacement

In patients with symptomatic severe aortic stenosis (AS), those who experienced readmission due to heart failure after transcatheter aortic valve replacement (TAVR) showed poor prognosis. Furthermore, poor B-type natriuretic peptide (BNP) improvement is associated with increased morbidity and mortality. However, little is known about the clinical parameters related to the change in BNP levels after TAVR procedure. This study population consisted of 127 consecutive patients of symptomatic severe AS with preserved ejection fraction (EF) who underwent transfemoral TAVR (TF-TAVR). Comprehensive transthoracic echocardiography was performed prior to the day of TF-TAVR. BNP was measured serially before and 1 year after TF-TAVR. The median BNP level was significantly decreased from 252.5 pg/ml to 146.8 pg/ml in all 127 patients 1 year after TF-TAVR (P < 0.01). However, the patients could be divided into 2 groups according to decrease (72%) or increase (28%) in plasma BNP level. Multivariate logistic regression analysis revealed that Aortic valve (AV) peak velocity, pre-procedural BNP, and larger left atrial volume index (LAVI) were found to be an independent predictor of increased BNP level 1 year after TAVR (OR 0.55, 95% CI 0.38-0.77; P < 0.01). LAVI were negatively correlated with the change in BNP level before and 1 year after TAVR (r = 0.47, P < 0.01). The ROC analysis demonstrated that 52.9 ml/m2 was the optimal cut-off value of LAVI for decreasing BNP 1 year after TAVR (area under the curve 0.69) with 64% sensitivity and 70% specificity. In addition to AV peak velocity and pre-procedural BNP, LAVI independently predicts future improvement of BNP levels 1 year after TAVR. Our findings indicate an additive predictive value of assessment of LAVI before TAVR procedure for risk stratification.

The clinical value of the apex beat as a marker of left atrial enlargement

BACKGROUND

The palpation of the apex beat, one of the most fundamental physical examinations, provides a clue to left ventricular (LV) dilatation and hypertrophy; however, its relation to left atrial (LA) volume has rarely been investigated.

METHODS

The clinical value of the apex beat, especially in relation to LA volume was studied in 138 consecutive patients. Patients were examined in the supine position for a palpable apex beat. When an apex beat was felt, the apex beat distance, defined as the distance from the mid-clavicular line to the lateral border of the apex beat, was measured. The LA and LV geometry were assessed using echocardiography.

RESULTS

Of the 138 patients, an apex beat was palpable in 52 (38%) patients and the apex distance of these 52 patients ranged from -2 to 8 cm. The parameters of LV dilatation or hypertrophy were significant according to univariate but not to multivariate analysis. Only LA volume index was significant both for the palpability of the apex beat (p=0.0042) and the apex distance (p=0.0017) by multivariate analysis. The best cut-off point for the apex distance was -1 cm for LA enlargement (sensitivity 61%, specificity 92%, p<0.0001).

CONCLUSIONS

The LA volume is the most significant factor for the palpability and leftward deviation of the apex beat. Palpation of the apex beat is a crucial diagnostic tool for the detection of not only LV dilatation or hypertrophy but also of LA enlargement.