Catheterization and Cardiovascular Interventions 87:E39–E43 (2016)
VALVULAR AND STRUCTURAL HEART DISEASES Original Studies Brain Natriuretic Peptide Levels Variation After Left Atrial Appendage Occlusion Ignacio Cruz-Gonzalez,1* MD, PhD, Jorge Palazuelos Molinero,2 MD, Maria Valenzuela,1 MD, Ignacio Rada,2 MD, Jose Angel Perez-Rivera,1 MD, PhD, Antonio Arribas Jimenez,1 MD, PhD, Tania Gabella,1 MD, Ana Beatriz Prieto,3 MD, nchez,1 MD, PhD Jorge Martın Polo,4 MD, and Pedro L. Sa Objective: To explore the variations of brain natriuretic peptide (BNP) secretion after left atrial appendage occlusion. Background: Left atrial appendage occlusion has been increasingly performed in the last few years, however little is known about the physiological consequences of left atrial appendage occlusion. Left atrial appendage regulates partially intravascular volume via release of brain natriuretic peptide. Brain natriuretic peptide levels have been related to increased risk of stroke in atrial fibrillation patients. Methods: Venous blood samples were obtained in consecutive patients undergoing left atrial appendage occlusion before, 24 hr after device implantation and at the first visit after discharge (45–60 days) for BNP measurement. Results: Left atrial appendage occlusion was performed in 34 patients with non-valvular atrial fibrillation and contraindication to long-term oral anticoagulation or at high-risk of bleeding. There were no differences in BNP levels between baseline and 24 hr after device implantation. However left atrial appendage closure resulted in a significant decrease in BNP levels at the first follow-up visit (45–60 days) compared to baseline measurements (759.90 pg ml21 vs. 636.90 pg ml21, P 5 0.013). Conclusions: Left atrial appendage occlusion modifies BNP levels. These levels decrease after left atrial appendage occlusion. The clinical consequences of these findings need to be evaluated in further studies. VC 2015 Wiley Periodicals, Inc. Key words: left atrial appendage; brain natriuretic peptide
Left atrial appendage (LAA) occlusion for prevention of ischemic events in patients with non-valvular atrial fibrillation (AF) is a continuously expanding procedure. The safety and efficacy of this technique have been shown [1,2]. However, it is unknown whether the LAA occlusion and the loss of its mechanical function has any significant pathophysiological implication . Under physiological conditions, the LAA has a fundamental role in the control of homeostasis via release of neurohormones such as brain natriuretic peptide (BNP). BNP is secreted from cardiomyocytes in response to ventricular volume expansion and pressure overload [3,4]. BNP levels are elevated in several diseases such as congestive heart failure, dilated cardiomyopathy, hypertrophic cardiomyopathy or hypertensive cardiomyopathy [5–7]. Also, in patients with AF, BNP levels C 2015 Wiley Periodicals, Inc. V
Cardiology Department, University Hospital of Salamanca, IBSAL, Salamanca, Espana 2 Cardiology Department, Gomez Ulla Hospital, Madrid, Spain 3 Gastroenterology Department, University Hospital of Salamanca, IBSAL, Salamanca, Espana 4 Neurology Department, University Hospital of Salamanca, IBSAL, Salamanca, Espana Conflict of interest: Dr Cruz-Gonzalez is proctor and consultant for Boston Scientific *Correspondence to: Ignacio Cruz-Gonzalez, MD, PhD, Associate Professor Cardiology Department, University Hospital of Salamanca, Paseo San Vicente, 58-182 37007, Salamanca, Espa~na. E-mail: [email protected]
or [email protected]
Received 9 January 2015; Revision accepted 6 April 2015 DOI: 10.1002/ccd.25985 Published online 29 May 2015 in Wiley Online Library (wileyonlinelibrary.com)
Cruz-Gonzalez et al.
TABLE I. Population Characteristics Age (years) Sex (men) Hypertension Diabetes Hyperlipidemia CHA2DS2VASc score HAS BLED score Type of AF Paroxysmal Permanent Baseline serum creatinine level (mg dl1) 45–60 days serum creatinine level (mg dl1) Baseline serum sodium levels (meq l1) 45–60 days serum sodium levels (meq l1) Left ventricle ejection fraction
TABLE II. 76.91 6.32 50% 88.2% 32.4% 41.2% 4.38 1.23 3.74 0.79 35.3% 64.7% 1.05 0.45 1.07 0.54 140.11 4.49 140.27 3.68 58.4% 4.5%
are higher than in control subjects, and these levels are reduced after sinus rhythm is recovered . Elevated levels of BNP after AF ablation is a strong predictor of arrhythmia recurrence [9–13] and it detects patients at increased risk of thromboembolic complications. Therefore BNP could be a risk marker for thromboembolic stroke . However, the impact of LAA occlusion on BNP levels is unknown. The aim of our study was to analyse the variations of plasma BNP levels in patients undergoing LAA closure procedure, taking BNP measurements before closing, 24 hr after occlusion and 45–60 days postimplantation.
ACP/Amulet (St Jude Medical) device Watchman (Boston Scientific) device Technical success Amount of contrast (ml) Left atrium mean pressure Intraprocedural complications
44% 56% 100% 65 10 ml 12.3 2.1 mm Hg 0%
TTE was performed 24 hr after procedure to rule out complications. All the patients were discharged with dual antiplatelet therapy (aspirin 100 mg day1 and clopidogrel 75 mg day1). First follow up visit was scheduled 45–60 days post-procedure; a new TEE was performed in that visit. Statistical Analysis A prospective study was performed. Continuous variables were presented as mean standard deviation or median and interquartile range. Qualitative variables were presented as absolute numbers and percentages. An assessment of the normality of data was performed with the Shapiro–Wilk Test. For non-normally distributed samples, the Wilcoxon signed ranks of related samples was used to assess any difference in median values. Values of P < 0.05 were considered statistically significant for all tests. All analyses were conducted using the statistical package IBM SPSS statics version 20 (IBM Corp).
Consecutive patients with non-valvular AF and contraindication to anticoagulation or at high risk of bleeding measured by HAS-BLED score undergoing percutaneous LAA closure in two centres were included . Prior to the intervention, all patients underwent transthoracic (TTE) and transesophageal (TEE) echocardiography to rule out the presence of thrombi and to take LAA measurements. All patients signed the informed consent prior to the procedure. The procedure was performed according to the previously described technique  using the Watchman (Boston Scientific) and the Amplatzer Cardiac Plug/ Amulet (St Jude Medical) devices under general anaesthesia, guided by fluoroscopy and TEE with two- and three-dimensional images. Venous blood samples were obtained to determine BNP levels pre-intervention, 24 hr after procedure and on the first follow-up visit after implantation (45–60 days). Patients with dilated cardiomyopathy, hypertrophic cardiomyopathy, hypertensive cardiomyopathy and those with signs and symptoms of heart failure were excluded; patients without the three planned BNP measurements were also excluded.
Of the 37 patients in whom the device was implanted in the study period (July 2012 to December 2013), 2 were excluded due to signs of heart failure at the time of implantation or follow-up and one patient died of non-cardiac causes before the first follow-up visit and he was also excluded. Consequently the final study population included 34 patients. Baseline and Procedural Characteristics
Baseline and procedural characteristics are summarized in Tables I and II. Technical success (implantation of the device) was obtained in all the patients without any intra-procedural complication. Complete closure was achieved in all patients (in one patient there was a leak detected by color Doppler flow