Chwyczko Tomasz, Dąbrowski Rafał, Maciąg Aleksander, Sterliński Maciej, Smolis-Bąk Edyta, Borowiec Anna, Kowalik Ilona, Łabęcka Andrada, Jankowska Agnieszka, Kośmicki Marek, Janas Jadwiga, Pytkowski Mariusz, Szwed Hanna
Second Coronary Artery Disease Department, Institute of Cardiology, Warsaw, Poland.
Ann Noninvasive Electrocardiol. 2013 Jul;18(4):369-78. doi: 10.1111/anec.12049. Epub 2013 May 3.
Right ventricular pacing (RVP) causes ventricular desynchronization and may lead to the development of heart failure (HF). Prolongation of atrioventricular delay (AVD) in DDDR pacemakers reduces unnecessary RV stimulation. The aim of the study was to verify the influence of RVP reduction on HF symptoms.
The study comprised 31 patients (17 men, mean age: 71.6 ± 8 yrs) with DDDR pacemaker implanted due to sinus node dysfunction (SND). At baseline, 28 patients did not present any symptoms of HF. Three patients were in NYHA class II. Patients were randomized either to 150 ms AVD or to minimizing right ventricular pacing (MRVP). Crossing over to the alternate mode took place after 4 months. Cardiopulmonary exercise test (CPX), echocardiography (ECHO) and BNP measurements were done before pacemaker implantation, after 4 and 8 months.
The percentage of RVP was significantly higher in 150 ms AVD than in MRVP: 81.7 ± 22.6 versus 14.2±20.5%, P < 0.0001. Patients with 150 ms mode had worse CPX parameters than those with MRVP mode: peak oxygen uptake was 14.2±4.3 versus 19.9±6.3 ml/kg per min, P = 0.0001, higher BNP concentrations: 72.3±48.3 versus 49.4±43.9 pg/ml, P = 0.001 and worse left ventricle [LV] function: ejection fraction: 53.2±6.7 versus 57.3±5.5%, P < 0.0001; LV diastolic diameter: 4.86±0.52 versus 4.66±0.5 cm, P < 0.01.
Predominant RVP in patients without symptoms of HF at baseline may be responsible for worse performance in cardiopulmonary exercise test, higher BNP concentrations and impairment of LV function. Specific DDDR pacemaker programming promotes intrinsic AV conduction and may prevent the development of pacing-induced HF.
右心室起搏（RVP）会导致心室不同步，并可能引发心力衰竭（HF）。双腔双感知率应答式起搏器（DDDR）中房室延迟（AVD）的延长可减少不必要的右心室刺激。本研究的目的是验证减少RVP对HF症状的影响。
本研究纳入31例因窦房结功能障碍（SND）植入DDDR起搏器的患者（17例男性，平均年龄：71.6±8岁）。基线时，28例患者无任何HF症状。3例患者为纽约心脏协会（NYHA）心功能II级。患者被随机分为150毫秒AVD组或最小化右心室起搏（MRVP）组。4个月后交叉至另一种模式。在起搏器植入前、4个月和8个月后进行心肺运动试验（CPX）、超声心动图（ECHO）和脑钠肽（BNP）测量。
150毫秒AVD组的RVP百分比显著高于MRVP组：81.7±22.6%对14.2±20.5%，P<0.0001。150毫秒模式组的CPX参数比MRVP模式组差：峰值摄氧量为14.2±4.3对19.9±6.3毫升/千克每分钟，P = 0.0001，BNP浓度更高：72.3±48.3对49.4±43.9皮克/毫升，P = 0.001，左心室（LV）功能更差：射血分数：53.2±6.7%对57.3±5.5%，P<0.0001；左心室舒张直径：4.86±0.52对4.66±0.5厘米，P<0.01。
基线时无HF症状患者中占主导的RVP可能是心肺运动试验表现更差、BNP浓度更高和左心室功能受损的原因。特定的DDDR起搏器程控可促进固有房室传导，并可能预防起搏诱导的HF的发生。
