Martínez Martínez J G, Ortuño Alcaraz D, Marín Ortuño F, Luján Martínez J, Ibáñez Criado A, Quiles Llorens J A, Sogorb Garri F
Servicio de Cardiología, Hospital General Universitario de
Rev Esp Cardiol. 1998 Jan;51(1):51-5.
Permanent cardiac pacing with a dual chamber pacemaker has become a valid alternative in treatment of patients with obstructive hypertrophic cardiomyopathy and refractory symptoms to pharmacological treatment, with a significant decrease of left ventricular outflow tract gradient.
To assess any modification of the gradient with dobutamine stress echocardiography.
We study 10 patients with obstructive hypertrophic cardiomyopathy and angina and/or dyspnea refractory to customary pharmacological treatment. A dual chamber pacemaker had been implanted 3-6 months previously. A dobutamine stress echocardiography was performed, beginning with a 10 microgram/kg/min infusion, with increases of 10 micrograms each 3 minutes until a maximum of 40. Modification of subaortic gradient, severity of systolic anterior motion of mitral valve (SAM, degree 0-3/3) and severity of mitral regurgitation (degree 0-4/4) were assessed.
Subaortic gradient decreased in all patients after pacemaker implantation (90 +/- 15 vs 20 +/- 10 mmHg; p < 0.001). With stress echocardiography the gradient increased in all patients (20 +/- 10 to 101 +/- 13 mmHg; p < 0.001). After implant there were only two patients with a +1 SAM, while during stress echocardiography SAM developed in all patients in +2 or +3 degree. Three patients had +1 mitral regurgitation after pacemaker implantation but during stress echocardiography 2-4/4 mitral regurgitation developed in all patients.
Permanent dual chamber pacing decreased left ventricular outflow tract gradient in patients with obstructive hypertrophic cardiomyopathy, but during dobutamine stress echocardiography obstruction echocardiographic signs appeared.
对于梗阻性肥厚型心肌病且药物治疗效果不佳的患者，双腔起搏器永久性心脏起搏已成为一种有效的治疗选择，可显著降低左心室流出道压差。
通过多巴酚丁胺负荷超声心动图评估压差的任何变化。
我们研究了10例梗阻性肥厚型心肌病患者，这些患者伴有心绞痛和/或对常规药物治疗无效的呼吸困难。均在3至6个月前植入了双腔起搏器。进行多巴酚丁胺负荷超声心动图检查，起始输注速度为10微克/千克/分钟，每3分钟增加10微克，直至最大剂量40微克。评估主动脉下压差的变化、二尖瓣收缩期前向运动（SAM，0至3/3级）的严重程度以及二尖瓣反流（0至4/4级）的严重程度。
起搏器植入后所有患者的主动脉下压差均降低（90±15 vs 20±10 mmHg；p<0.001）。负荷超声心动图检查时，所有患者的压差均升高（20±10至101±13 mmHg；p<0.001）。植入后仅有2例患者SAM为+1级，而在负荷超声心动图检查时所有患者的SAM发展为+2或+3级。起搏器植入后3例患者有+1级二尖瓣反流，但在负荷超声心动图检查时所有患者均出现2至4/4级二尖瓣反流。
永久性双腔起搏可降低梗阻性肥厚型心肌病患者的左心室流出道压差，但在多巴酚丁胺负荷超声心动图检查期间会出现梗阻性超声心动图征象。
