Pietrucha Artur, Piwowarska Wiesława
Klinika Choroby Wieińcowej, Instytut Kardiologii Collegium Medicum Uniwersytetu Jagiellońskiego Krakowski Szpital Specjalistyczny im. Jana Pawła II, Kraków.
Kardiol Pol. 2004 Sep;61 Suppl 2:II103-9.
Sick sinus syndrome (SSS) is frequently observed in patients with coronary artery disease (CAD). The influence of nitrates administered in CAD on sinus node function has not been established yet. It is not yet clear whether nitrates improve the sinus node blood supply or whether they directly influence the sinus node authomaticity. The second hypothesis is seems to be supported by the results of animal studies.
Evaluation of sinus node chronotropic response to the stimulation by nitric oxide (NO) donors, after pharmacological blockade in patients with different types of SSS with ischemic etiology. We studied 102 patients with suspected sinus node dysfunction and clinically diagnosed ischemic heart disease.
Test of sinus node chronotropic response was performed after pharmacological blockade with atropine and propranolol. A bolus of 100 microg nitroglycerin was administered to all patients. The following parameters were assessed: heart rate before (HR(NTG 0)), and after NTG bolus; maximal (HRNTG max) and mean at 5t second (HR(NTG 5)). Based on results of stimulation patients were divided into two groups: group I--70 patients with electrophysiological signs of SSS and group II--32 patients without the above mentioned signs. One subgroup with decreased IHR alone and three subgroups with different types of SSS were assigned from group I.
Heart rate before (HR0) and after bolus of 100 microg nitroglycerin (HR(NTG max), HR(NTG 5)) were significantly lower in patients with SSS than in subjects with normal sinus node function. There were no significant differences of absolute and relative HR increase after NTG bolus between both groups of patients. The values of HR(NTG max) and HR(NTG 5) did not vary significantly between subgroups of patients with different types of SSS. Patients with intrinsic SSS revealed positive correlation between HR0 and both: HRmax and HR(NTG 5). whereas persons with other types of SSS did not show this relation.
(1) Significant positive chronotropic response of sinus node to the stimulation by NO donor was observed in both patients: with and without electrophysiological signs of SSS. (2) The positive chronotropic response of sinus node to NTG bolus was observed despite of type of SSS.
病态窦房结综合征（SSS）在冠状动脉疾病（CAD）患者中经常出现。CAD患者使用硝酸盐对窦房结功能的影响尚未明确。目前尚不清楚硝酸盐是改善窦房结血供还是直接影响窦房结自律性。动物研究结果似乎支持后一种假设。
评估在不同类型缺血性病因的SSS患者中，经药物阻断后窦房结对一氧化氮（NO）供体刺激的变时反应。我们研究了102例疑似窦房结功能障碍且临床诊断为缺血性心脏病的患者。
在使用阿托品和普萘洛尔进行药物阻断后，进行窦房结变时反应测试。向所有患者静脉注射100微克硝酸甘油。评估以下参数：注射硝酸甘油前（HR(NTG 0)）和注射后心率；最大心率（HRNTG max）和第5秒平均心率（HR(NTG 5)）。根据刺激结果，患者分为两组：I组——70例有SSS电生理体征的患者和II组——32例无上述体征的患者。从I组中分出单独固有心率降低的一个亚组和不同类型SSS的三个亚组。
SSS患者注射100微克硝酸甘油前（HR0）和注射后（HR(NTG max)，HR(NTG 5)）的心率显著低于窦房结功能正常的受试者。两组患者注射硝酸甘油后绝对和相对心率增加无显著差异。不同类型SSS患者亚组之间的HR(NTG max)和HR(NTG 5)值无显著差异。固有性SSS患者的HR0与HRmax和HR(NTG 5)均呈正相关，而其他类型SSS患者未显示这种关系。
（1）在有和没有SSS电生理体征的患者中均观察到窦房结对NO供体刺激有显著的正性变时反应。（2）无论SSS类型如何，均观察到窦房结对硝酸甘油注射有正性变时反应。
