中村 隆志¹, 北村 浩一², 古川 啓三², 辻 康裕¹, 高橋 徹¹, 国重 宏¹, 下尾 和敏², 東 秋弘², 朝山 純², 勝目 紘²

Takashi NAKAMURA¹, Hirokazu KITAMURA², Keizo FURUKAWA², Yasuhiro TSUJI¹, Tohru TAKAHASHI¹, Hiroshi KUNISHIGE¹, Kazutoshi SHIMOO², Akihiro AZUMA², Jun ASAYAMA², Hiroshi KATSUME²

¹松下記念病院第三内科, ²京都府立医科大学第二内科

¹The Third Department of Internal Medicine, Matsushita Memorial Hospital, ²The Second Department of Internal Medicine, Kyoto Prefectural University of Medicine

キーワード : Hypertrophic cardiomyopathy, Doppler echocardiography, Mid-ventricular obstruction

To assess the intraventricular flow conditions in 4 patients with hypertrophic cardiomyopathy with mid-ventricular obstruction, we utilized Doppler echocardiography including real-time color flow imaging, continuous and pulsed wave Doppler ultrasounds. By color flow mapping, obstructive signals consisted of rapid-velocity aliasing and mosaic-colored jets appeared at the mid-ventricular level during both systole and diastole. High velocity jets with late systolic peak ranged from 2.3 to 4.0 m/sec (mean 3.3) by continuous wave Doppler suggested the existence of systolic pressure gradient at the midventricle. In addition, peak mitral rapid filling velocities ranged from 25 to 45 cm/sec (mean 38) were accellerated at the midventricle, ranged from 75 to 135 cm/sec (mean 114) by pulsed wave mapping. Peak flow velocities during isovolumic relaxation period were also rapid at the mid-ventricle. These findings indicated the existence of characteristic intraventricular flows in mid-ventricular obstruction during not only systole but diastole.
Doppler echocardiography is safe and useful technique to assess the intraventricular flow conditions in mid-ventricular obstruction.