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冠動脈複雑性病変に対するcoronary rotational atherectomy (RA)は有効な血行再建術の一つとして普及しつつあるが, 治療効果等に関しては報告が少ない.今回われわれはRAの初期成績および遠隔期成績について検討した.1997年12月～2000年4月の間に当院でRAを施行した連続30例, 32病変を対象とした.RA後バルーンカテーテルによる低圧拡張の追加を基本方針とし, 必要に応じて高圧拡張・ステント留置を行った.残存狭窄50%未満かつTIMI3をもって手技成功とし, 遠隔期(3～6カ月後)造影所見における50%以上の狭窄を再狭窄とした.標的病変は全てが高度石灰化を伴う複雑性病変(タイプB2病変が22病変(69%), タイプC病変が10病変(31%))であった.手技成功は28病変(87.5%)に得られ, 平均径狭窄率は78±9%から20±14%に改善した.手技不成功の原因としてはガイドワイヤー不通過, プラットホーム形成困難等であり, RAが施行可能であった28病変はすべて手技成功が得られた.遠隔期に17病変において冠動脈造影を施行し, 再狭窄を8例(47%)に認め, 平均径狭窄率は52±25%であった.再狭窄を認めた全例に再血行再建(RA1例・ステント留置7例)を施行したが, RAによるlesion modificationによって, RA以外の手技にて良好な初期成功率が得られた.再狭窄率は低くないが, 慎重な症例選択と手技を行えば, RAは石灰化を有する複雑性病変に対し, 粥腫の切除(debulking)のみでなくlesion modificationの面でも有用な治療手技であると考えられた.

Acute coronary syndrome(ACS) and acute aortic dissection(AAD) are life-threatening conditions which can be difficult to differentiate in the emergency room because of the similarity of clinical presentations. In addition, ACS can be caused in AAD as a complication of the dissecting process. Usual form of ACS is caused by an obstruction of the epicardial coronary arteries, which is initiated with the rupture of an unstable atherosclerotic plaque complicated with subsequent thrombus formation(Libby , 2001). On the other hand, ACS secondary to AAD is caused by malperfusion of the coronary artery by an obstruction of the orifice as a complication of the dissecting process. If AAD is compicated with ACS, prognosis becomes worse and the treatment of choice may be totally different from usual ACS. Medications and procedures which are usually used in cases of ordinary ACS, such as Heparin, antiplatelets, thrombolytic agents and catheter interventions, may be harmful in ACS secondary to AAD. So it is of great importance to make a correct diagnosis of ACS secondary to AAD for better treatment and survival.

Subtle variations in QRS morphology occurs during idiopathic outflow tract ventricular tachycardia (OTVT), but no studies have clarified the prevalence and characteristics of the OTVT with altered QRS morphology following radiofrequency catheter ablation (RFA), which then require an additional RF application at a different portion of the outflow tract to abolish OTVT. Of 202 patients with a monomorphic VT or premature ventricular contraction (PVC) originating from the outflow tract, 6 (3%) showed changes in QRS morphology in the OTVT following RFA, requiring an additional RF application to the outflow tract at a different portion. In all six patients, RFA was applied for the first or second OTVT to a right or left ventricular endocardial site, with the other site being the left sinus of Valsalva. In each patient, OTVT before or after the changes in QRS morphology had characteristic ECG findings originating from a particular portion of the outflow tract. Changes in QRS morphology consistently included an increase or decrease in R wave amplitude in all inferior leads. Detailed continuous observation of QRS morphology in OTVT, especially R wave amplitude in inferior leads, is important for identifying changes of QRS morphology during catheter ablation. Mapping and ablation at a different portion of the outflow tract is then needed for cure.