Bonow R O, Frederick T M, Bacharach S L, Green M V, Goose P W, Maron B J, Rosing D R
Am J Cardiol. 1983 May 1;51(8):1386-91. doi: 10.1016/0002-9149(83)90317-x.
Many patients with hypertrophic cardiomyopathy (HC) have impaired left ventricular (LV) rapid diastolic filling. To quantitate the contribution of atrial systole to LV filling, we used radionuclide angiography to study 30 normal volunteers and 42 patients with HC before and after oral administration of verapamil (320 to 560 mg/day). LV time-activity curves were constructed by combined forward and reverse gating from the R wave, and the onset of atrial systole was determined by the P-R interval. The percent of LV stroke volume filled during rapid diastolic filling and atrial systole was then computed. Peak LV filling rate during rapid diastolic filling was expressed in end-diastolic volume (EDV)/second. Peak rate of rapid diastolic filling was not different in normal patients and those with HC (3.3 +/- 0.6 versus 3.3 +/- 1.1 EDV/s) and was within the normal range in 34 patients with HC (81%). However, the contribution to LV filling volume by rapid diastolic filling was diminished in patients with HC (83 +/- 7% normal, 67 +/- 17% HC, p less than 0.001) and the contribution of atrial systole was increased (16 +/- 8% normal, 31 +/- 18% HC, p less than 0.001). LV filling volume during atrial systole was above the upper normal limit of 31% in 17 patients (40%), including 13 patients with a normal peak filling rate. After verapamil, peak filling rate increased (to 4.2 +/- 1.2 EDV/s, p less than 0.001), percent LV filling during rapid diastolic filling increased (to 83 +/- 7%, p less than 0.001), and percent LV filling during atrial systole decreased (to 16 +/- 9%, p less than 0.001). Percent LV filling volume during atrial systole was abnormal after verapamil in only 3 patients (7%). Hence, although the peak rate of rapid diastolic filling may be normal in patients with HC, the contribution to LV filling by rapid diastolic filling is reduced and that of atrial systole is thereby increased. Increased rate and magnitude of rapid diastolic filling during verapamil is associated with decrease and normalization of the contribution of atrial systole to LV filling. These data suggest that many patients with HC are at risk of hemodynamic decompensation with the onset of atrial fibrillation or other tachyarrhythmias and loss of the atrial contribution to LV filling. This risk may be reduced during verapamil therapy.
许多肥厚型心肌病（HC）患者左心室（LV）快速舒张期充盈受损。为了定量心房收缩对左心室充盈的贡献，我们采用放射性核素血管造影术对30名正常志愿者和42例HC患者在口服维拉帕米（320至560毫克/天）前后进行了研究。通过从R波进行正向和反向联合门控构建左心室时间-活动曲线，并通过P-R间期确定心房收缩的起始。然后计算快速舒张期充盈和心房收缩期所充盈的左心室每搏量百分比。快速舒张期充盈时的左心室充盈峰值速率以舒张末期容积（EDV）/秒表示。正常患者和HC患者的快速舒张期充盈峰值速率无差异（3.3±0.6对3.3±1.1 EDV/秒），42例HC患者中有34例（81%）处于正常范围内。然而，HC患者快速舒张期充盈对左心室充盈量的贡献减少（正常人为83±7%，HC患者为67±17%，p<0.001），而心房收缩的贡献增加（正常人为16±8%，HC患者为31±18%，p<0.001）。17例患者（40%）心房收缩期的左心室充盈量高于31%的正常上限，其中包括13例充盈峰值速率正常的患者。服用维拉帕米后，充盈峰值速率增加（至4.2±1.2 EDV/秒，p<0.001），快速舒张期充盈时的左心室充盈百分比增加（至83±7%，p<0.001），心房收缩期的左心室充盈百分比降低（至16±9%，p<0.001）。服用维拉帕米后，仅3例患者（7%）心房收缩期的左心室充盈量百分比异常。因此，尽管HC患者快速舒张期充盈的峰值速率可能正常，但快速舒张期充盈对左心室充盈的贡献减少，从而心房收缩的贡献增加。维拉帕米治疗期间快速舒张期充盈速率和幅度的增加与心房收缩对左心室充盈的贡献减少及恢复正常相关。这些数据表明，许多HC患者在发生心房颤动或其他快速心律失常以及心房对左心室充盈的贡献丧失时存在血流动力学失代偿的风险。在维拉帕米治疗期间，这种风险可能会降低。
