Brignole M, Menozzi C, Gaggioli G, Musso G, Foglia-Manzillo G, Mascioli G, Fradella G, Bottoni N, Mureddu R
Section of Arrhythmology, Ospedali Riuniti, Lavagna, Italy.
Am Heart J. 1998 Aug;136(2):264-8. doi: 10.1053/hj.1998.v136.89911.
In patients affected by carotid sinus hypersensitivity, long-term vasodilator therapy might increase the risk of syncopal episodes by reducing systolic blood pressure and venous return to the heart.
Thirty-two patients (mean age 73 +/- 9 years; 20 men) who met all the following criteria were included: (1) one or more episodes of syncope occurring during long-term (>6 months) treatment with angiotensin-converting enzyme inhibitors, long-acting nitrates, calcium antagonists, or a combination of these; (2) a positive response to carotid sinus massage, defined as the reproduction of spontaneous syncope in the presence of ventricular asystole > or =3 seconds or a fall in systolic blood pressure > or =50 mm Hg; (3) negative workup for other causes of syncope. The patients were randomly assigned to continue or to discontinue use of vasodilators; carotid sinus massage was repeated 2 weeks after randomization. By the end of the study period, the baseline values of systolic blood pressure were significantly different between the 2 groups of patients both in supine (P=.01) and upright (P=.03) positions. Syncope had been induced by carotid sinus massage in 81% of patients in the "on-vasodilator" group and in 62% of patients in the "off-vasodilator" group (P=.21). The cardioinhibitory reflex was of similar magnitude in the 2 groups, being found in 50% of the patients in each group, with a maximum ventricular pause of 7.1 +/- 2.7 and 6.7 +/- 1.8 seconds, respectively. The percentage decrease of blood pressure did not differ between the 2 groups, even if, in absolute values, the baseline difference of blood pressure roughly persisted for the duration of the test. In consequence of that, the rise of blood pressure to similar values was delayed approximately 30 seconds in the "on-vasodilator" group and took more than 2 minutes to return to baseline values.
In patients affected by carotid sinus hypersensitivity, chronic vasodilator therapy does not have a direct effect on carotid sinus reflexivity, although the delayed recovery of pretest blood pressure values could indirectly potentiate the severity of the clinical manifestations of the syndrome. The persistence of hypotension for a longer time after the end of the massage suggests that vasodilators cause an impairment of compensatory mechanisms.
在患有颈动脉窦过敏的患者中，长期血管扩张剂治疗可能会通过降低收缩压和减少静脉回流至心脏而增加晕厥发作的风险。
纳入了32例患者（平均年龄73±9岁；20例男性），这些患者符合以下所有标准：（1）在使用血管紧张素转换酶抑制剂、长效硝酸盐、钙拮抗剂或这些药物的组合进行长期（>6个月）治疗期间发生一次或多次晕厥发作；（2）对颈动脉窦按摩有阳性反应，定义为在心室停搏≥3秒或收缩压下降≥50mmHg的情况下再现自发性晕厥；（3）对其他晕厥原因的检查结果为阴性。患者被随机分配继续或停用血管扩张剂；随机分组后2周重复进行颈动脉窦按摩。到研究期结束时，两组患者在仰卧位（P = 0.01）和直立位（P = 0.03）时收缩压的基线值均有显著差异。“使用血管扩张剂”组中81%的患者和“停用血管扩张剂”组中62%的患者通过颈动脉窦按摩诱发了晕厥（P = 0.21）。两组的心脏抑制反射程度相似，每组50%的患者出现该反射现象，最大心室停搏分别为7.1±2.7秒和6.7±1.8秒。两组之间血压下降的百分比没有差异，即使在绝对值上，血压的基线差异在测试期间大致持续存在。因此，“使用血管扩张剂”组血压升高至相似值的时间延迟了约30秒，并且需要超过2分钟才能恢复到基线值。
在患有颈动脉窦过敏的患者中，慢性血管扩张剂治疗对颈动脉窦反射性没有直接影响，尽管测试前血压值的延迟恢复可能会间接增强该综合征临床表现的严重程度。按摩结束后低血压持续较长时间表明血管扩张剂会损害代偿机制。
