Augmentation index is associated with B-type natriuretic peptide in patients with paroxysmal atrial fibrillation

Abstract

B-type natriuretic peptide (BNP) levels have been shown to be elevated in patients with paroxysmal atrial fibrillation (PAF); however, the underlying mechanisms have not been fully elucidated. Earlier, we reported that an increase in the augmentation index (AI), which is an index of wave reflection and arterial stiffness, is associated with PAF. In this study, we investigate the relationship between the BNP level and AI in patients with PAF. We enrolled 92 patients with a history of PAF and 90 age-and gender-matched individuals without PAF. AI was calculated using applanation tonometry of the radial artery when all patients were on sinus rhythm. Plasma BNP levels were measured simultaneously. An arterial stiffness parameter, the cardio-ankle vascular index (CAVI), was also evaluated. The increased AI in patients with PAF correlated with the elevation of the BNP level (r¼0.47, Po0.01). When PAF patients were classified into tertiles on the basis of the BNP level, the left atrial volume index, left ventricular mass index, AI and CAVI increased, and mitral annular e¢ velocity (e¢), as an index of left ventricular diastolic pressure, decreased with BNP tertiles. AI was also associated with e¢ and left ventricular mass index. Multiple regression analysis showed that the AI in PAF patients independently correlated with BNP levels. This study showed that AI was an independent correlate of the BNP level in PAF patients. Left ventricular diastolic dysfunction, which linked to an increase in arterial stiffness, may be involved in the elevated BNP level. INTRODUCTIONThe B-type natriuretic peptide (BNP) is a neurohormone secreted from cardiac ventricles in response to ventricular volume and pressure overload. 1 The BNP level does not only significantly correlate with the left ventricular (LV) filling pressure but also reflects symptomatic LV dysfunction and prognosis. 2 Although BNP has been reported to be an excellent screening tool for LV dysfunction, some patients with paroxysmal atrial fibrillation (PAF) or coronary artery disease have been shown to have a high BNP level, independent of LV systolic function; 3,4 however, the underlying mechanisms of the increase in BNP level in patients with PAF have not been fully elucidated.Our recent study showed that the augmentation index (AI) obtained from the radial artery is increased in patients with PAF. 5 AI, determined from either a directly measured or derived central arterial pressure wave form, has been proposed as a measure of aortic stiffness and wave reflection. 6 Earlier studies have shown that AI is closely related to several risk factors for atherosclerosis 7 and cardiovascular diseases. 8 AI can be determined noninvasively by pulse wave

Arterial stiffness determined according to the cardio-ankle vascular index is associated with paroxysmal atrial fibrillation: a cross-sectional study

“…This study showed a positive correlation between the CAVI and the radial augmentation index, suggesting that an increase in arterial stiffness affects LV afterload. In line with our previous studies,16 22 this study also found that the CAVI was positively associated with the LV mass index and left atrial size. Another potential mechanism for the association between arterial stiffness and AF is that increased arterial stiffness predisposes individuals to a generalised cardiovascular inflammatory response 23 24.…”

“…Multiple logistic regression analysis was performed to evaluate the relationships between paroxysmal AF and increasing CAVI, aspects of blood pressure and echocardiographic parameters. The sample size was determined on the basis of the estimated CAVI values reported in our other study 16. We assumed a CAVI of 8.8±1.0 (mean±SD) in the control group and 9.0±1.0.…”

Relations of Arterial Stiffness and Brachial Flow–Mediated Dilation With New-Onset Atrial Fibrillation

“…13 Elevated augmentation index has been associated with lone AF recurrence, 40 paroxysmal AF, 41 and elevated Brain-Natriuretic Peptide (BNP) levels in paroxysmal AF. 42 In our study, the association between augmentation index and newonset AF was significant even after adjusting for hypertension Episodic increases in pulse pressure in individuals with a stiff aorta may contribute to increased risk of AF, accounting for left atrial size or left ventricular mass. 12 Acute increases in pulsatile load likely increase left atrial distending pressure, 43 cause neurohormonal activation, 44 and lead to generalized cardiovascular inflammatory response, 45 which may contribute to AF development.…”

Inflammation in Ischemic Stroke Subtypes

“…However, other studies that have assessed the markers of arterial stiffness in patients with atrial fibrillation, have evaluated both PWV and Aix [176,177].…”