Betocchi Sandro, Elliott Perry M, Briguori Carlo, Virdee Munmohan, Losi Maria Angela, Matsumura Yoshihisa, Miranda Marianna, McKenna William J, Chiariello Massimo
Department of Clinical Medicine, Cardiovascular & Immunological Sciences, Federico II University, Naples, Italy.
Pacing Clin Electrophysiol. 2002 Oct;25(10):1433-40. doi: 10.1046/j.1460-9592.2002.01433.x.
To assess the effects of chronic dual chamber pacing (DDD) on LV diastolic function in obstructive hypertrophic cardiomyopathy (HCM), 21 patients with obstructive HCM paced for refractory symptoms were studied at baseline and at 3 and 12 months. HCM patients were matched to 21 patients with obstructive HCM on conventional treatment. Left atrial fractional shortening was calculated by M-mode echocardiography; this index reflects LV end-diastolic pressure. LV outflow tract gradient decreased 65 +/- 21% with DDD pacing and the NYHA class improved (P = 0.033). Left atrial fractional shortening worsened with DDD pacing (P < 0.001). Patients with abnormal baseline left atrial fractional shortening (< 16%) were older, had a higher NYHA class, and had more severe mitral regurgitation. In this subgroup, left atrialfractional shortening did not worsen with DDD pacing and the NYHA class improved more than in patients with normal left atrialfractional shortening (P = 0.033). In conclusion, chronic DDD pacing reduces obstruction but impairs diastolic function in HCM. In patients with normal diastolic function, the untoward effects of pacing on diastolic function are more evident than in patients with abnormal diastolic function at baseline. This suggests that DDD pacing might be beneficial in a subgroup of patients with obstructive HCM and abnormal diastolic function.
为评估慢性双腔起搏（DDD）对梗阻性肥厚型心肌病（HCM）左心室舒张功能的影响，对21例因难治性症状而行起搏治疗的梗阻性HCM患者在基线、3个月和12个月时进行了研究。将HCM患者与21例接受传统治疗的梗阻性HCM患者进行匹配。通过M型超声心动图计算左心房分数缩短率；该指标反映左心室舒张末期压力。DDD起搏使左心室流出道压差降低65±21%，纽约心脏协会（NYHA）心功能分级改善（P = 0.033）。DDD起搏使左心房分数缩短率恶化（P < 0.001）。基线左心房分数缩短率异常（< 16%）的患者年龄更大，NYHA心功能分级更高，二尖瓣反流更严重。在该亚组中，DDD起搏未使左心房分数缩短率恶化，且NYHA心功能分级改善程度大于左心房分数缩短率正常的患者（P = 0.033）。总之，慢性DDD起搏可减轻梗阻，但会损害HCM患者的舒张功能。在舒张功能正常的患者中，起搏对舒张功能的不良影响比基线舒张功能异常的患者更明显。这表明DDD起搏可能对梗阻性HCM且舒张功能异常的亚组患者有益。
