Effect of Left Ventricular Dyssynchrony on Plasma B-Type Natriuretic Peptide Levels in Patients With Long-Term Right Ventricular Apical Pacing

Abstract

SUMMARYRight ventricular apical pacing (RAP) has been reported to have the potential to lead to left ventricular (LV) dyssynchrony and impaired LV function. The plasma level of Btype natriuretic peptide (BNP) is increased in the state of abnormal ventricular wall stretch. Therefore, the aim of the present study was to examine the effect of LV dyssynchrony on BNP levels in patients with chronic RAP.Thirty-four patients (17 women, age 69 ± 11 years) with preserved LV systolic function on permanent RAP (duration, 7.0 ± 4.7 years) underwent conventional echo-Doppler assessment and tissue Doppler imaging. Twenty-two normal subjects (8 women, age 66 ± 9 years) served as controls. The standard deviation (SD) and dispersion of the time-topeak systolic velocity (TPV) among the 6 basal LV segments were used as the indexes of LV dyssynchrony.Compared with control subjects, RAP patients had prolonged TPVs and heterogeneous LV contraction with greater values of TPV-SD (18 ± 8 ms versus 39 ± 15 ms, P < 0.001) and TPV-dispersion (42 ± 20 ms versus 93 ± 31 ms, P < 0.001). There were significant correlations between BNP levels and the indexes of LV dyssynchrony (r = 0.41, P = 0.017 for TPV-SD; r = 0.46, P = 0.006 for TPV-dispersion).RAP is associated with LV dyssynchrony, which may accelerate BNP secretion. (Int Heart J 2008; 49: 165-173) Key words: B-type natriuretic peptide (BNP), Tissue Doppler, Dyssynchrony, Echocardiography, Pacing RIGHT ventricular apical pacing (RAP) has been reported to have the potential to lead to left ventricular (LV) dysfunction even in the absence of structural heart disease. Underlying mechanisms of impaired LV function during RAP include alterations of cellular structure and ventricular geometry, systolic and diastolic dysfunction, mitral regurgitation, and increased left atrial diameters.1-5) Systolic dyssynchrony may also play a role in deteriorating LV pump function because From the

Left Ventricular Systolic Dysfunction Induced by Ventricular Ectopy

“…In addition, the absence of fibrosis, increased apoptosis and mitochondrial dysfunction as well as the normalization of LV diastolic dilatation after cessation of PVCs supports a distinct mechanism from tachycardia-induced CM. 14, 21, 28-31 Alternatively, frequent PVCs may cause LV dysynchrony similar to chronic right ventricular pacing 32-35 , which has been associated with higher mortality and a greater incidence of LV dysfunction 6, 36 . The abnormal pattern of electrical activation and LV dyssynchrony 34, 37-39 resulting from these PVCs may cause disruption and further progression of dysynergic LV wall motion 40-42 .…”

Interpretation and Use of Natriuretic Peptides in Non-Congestive Heart Failure Settings

“…In 34 patients with preserved LV systolic function on permanent RV apical pacing, RV apical pacing is associated with LV dyssynchrony and subsequent accelerated BNP secretion 60. In a study involving 43 children and adolescents with high-grade second degree or complete atrioventricular conduction block, plasma BNP levels were significantly higher in patients without pacemaker than in those with permanent pacemaker.…”

Right Ventricular Pacing and Mechanical Dyssynchrony

“…Other studies have also found that paced subjects have greater systolic dyssynchrony, as quantified by SD-TVI, while paced from the RV, even when paced subjects had normal EF (Kawanishi et al 2008;Zhang et al 2008b). The degree of longitudinal systolic dyssynchrony was similar to that of a group of HF patients with EF of less than 35% (Zhang et al 2008a).…”

“…Plasma levels of Btype natriuretic peptide (BNP; a marker of abnormal ventricular wall stretch) were also increased, and EF was reduced (Kawanishi et al 2008). Mechanical dyssynchrony was modestly correlated with BNP, but no correlations between dyssynchrony and EF were presented.…”