Page 20 - Delaware Medical Journal August 2015
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The Effects of Right Ventricular Apical Pacing Frequency on Left Ventricle Function and Pulmonary Artery Pressure
Zaher Fanari, MD; Sumaya Hammami, MD, MPH; Muhammad Baraa Hammami, MD; Safa Hammami, MD; Mossaab Shuraih, MD
Objective: We studied the effect of the frequency of right ventricular (RV) pacing on left ventricle (LV) function pulmonary hypertension.
Background: The incidence of new or worsening pulmonary hypertension after permanent pacemaker (PPM) or implantable cardioverter defibrillator (ICD) lead placement has not been well investigated.
Methods: We reviewed the charts of all patients undergoing PPM or ICD lead placement in our electrophysiology laboratory from December 2007 to December 2012.
Results: Two hundred and six patients (120 with PPM and 86 with ICD) had baseline echocardiography within six months before, and a follow up study at least six months after lead insertion. The mean age was 74 ±14 years;
56 percent were men. The follow-up period was 29 ±19 months. RV pacing was associated with a worsening of
left ventricular ejection fraction (LVEF) in patients with high frequency of RV (55 ±16 vs. 44 ±18; P=0.001), but
not with those with low frequency pacing (55 ±16 vs. 54 ±17; P=0.87). Similarly, RV pacing was associated with
a worsening in both right ventricular systolic pressure (RVSP) (42 ±14 vs. 48 ±15; P=0.01) and Pulmonary Artery Systolic Pressure (PASP) (50 ±17 vs. 56 ±18; P=0.005) in patients with high frequency RV, but not in those with low frequency RV pacing [RVSP (43 ±12 vs. 46 ±13; P=0.06) and PASP (51 ±15 vs. 54 ±16; P=0.11)].
Conclusion: PPM or ICD lead implantation worsens LV function and pulmonary hypertension in patients with high frequency of RV pacing frequency. This is probably caused by the mechanical dyssynchrony induced by RV pacing.
Key Words: Tricuspid regurgitation, mitral regurgitation, right ventricular pacing, permanent pacemaker, implantable cardioverter defibrillator
IntroductionSince the introduction of an endocardial transvenous lead for permanent cardiac pacing in 1959, the technology in the
implantation for permanent pacemaker (PPM) and implantable 1 Right ventricular (RV) apical pacing induces an iatrogenic intraventricular delay of electrical desynchronization.2 This dyssynchrony may lead to some degree
of moderate left ventricle (LV) dysfunction.3-5 There are studies even showing the development of pacing-induced cardiomyopathy in patients with normal left ventricular ejection fraction (LVEF) after long term right ventricular pacing.6 However the impact of this dyssynchrony on pulmonary hypertension is unclear.
We studied the effect of transvenous leads implantation and the frequency of RV pacing on pulmonary artery pressure.
METHODS
All charts of patients who underwent placement of a PPM or ICD lead placement at our electrophysiology laboratory between December 2001 and December 2006 were reviewed. Patients were included in the study if a baseline echocardiography within six months before and a follow up study at least six months
after lead insertion was available. Patients with Bi-Ventricular pacemaker devices, lead replacement or QRS>120 msec were excluded. The patients were divided depending on the degree
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Del Med J | August 2015 | Vol. 87 | No. 8
Abstract
