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We estimated the benefit of a sirolimus-eluting stent (SES, Cypher) for diffuse (> 10 mm) in-stent restenosis (ISR) inside bare metal stents (BMS) because the feasibility of the SES was not confirmed after its recent approval in Japan. Clinical and angiographic outcomes after SES implantation to 93 diffuse ISR were compared with those of 3 groups treated by plain old balloon angioplasty (POBA, (n = 54)), cutting balloon angioplasty (CB, (n = 24)), and BMS (n = 41) in a series of 153 patients whose follow-up quantitative coronary angiography (QCA) evaluated 3-9 months after the treatments was obtained from January 2003 through December 2005. For 33 lesions in the SES group, 12-month follow-up QCA results were obtained and compared with those at 6 months. Ticlopidine (200 mg/day) was prescribed for at least 12 weeks after SES implantation and for 2 weeks after BMS in addition to aspirin (81-100 mg/day). Patient characteristics and the characteristics of previous implanted BMS in the SES group were not significantly different from those in the other groups. Death from cardiac causes and nonfatal myocardial infarction did not occur in any group. Stent thrombosis was not observed in the BMS and SES groups. The incidence of repeat target lesion revascularization (re-TLR) in the SES group (3.23%) was significantly lower compared with that of the POBA (37.0%), CB (25.0%), and BMS (29.3%) groups (P < 0.001, respectively). Late loss in the SES group (0.44 +/- 0.41 mm) was significantly smaller than that in the BMS group (1.34 +/- 0.74 mm) (P < 0.05). The rate of recurrent ISR (re-ISR) in SES (5.38%) was significantly lower than that in POBA (46.3%), CB (41.7%), and BMS (46.3%) (P < 0.001, respectively). The QCA variables at 6 months in the SES group were not significantly different from those at 12 months. Thus, SES implantation for diffuse ISR was far superior since it markedly reduced the incidence of re-TLR with re-ISR at up to 6-months follow-up. In addition, this angiographic patency after SES implantation continued until 12 months.

The efficacy of long-term drug therapy for patients with hypertrophic obstructive cardiomyopathy (HOCM) remains unclear. This study was performed to characterize the echocardiographic findings of patients responsive to drug therapy.Left ventricular outflow tract (LVOT) gradient and morphologic characteristics of the septum, posterior wall, and mitral valve were measured echocardiographically in 35 Japanese patients. The mean follow-up time was 41+/-22 months.Long-term drug therapy was effective in 14 patients and ineffective in 21 patients. Five of the refractory patients required mitral valve replacement to become free of symptoms. Only 5 of 21 patients whose LVOT gradient was 100 mm Hg were responsive to drug therapy, whereas 9 of 14 patients whose LVOT gradient was100 mm Hg were responsive to drug therapy. Seven of eight patients with an asymmetric septal hypertrophy (ASH) ratio==1.3 and LVOT gradient100 mm Hg were responsive to drug therapy. Only 3 of 16 patients with an ASH ratio1.3 were responsive to drug therapy. There was no correlation between the efficacy of drug therapy and the morphology of the mitral valve or the width of the LVOT.Our results demonstrate that drug therapy effectively reduces the LVOT gradient in patients with asymmetric septal hypertrophy and a less severe LVOT gradient.

重症虚血性心疾患の急性期に認められる致死性不整脈に対し, 塩酸ニフエカラントの投与を行った5症例を経験した.有効例は3症例であり, 2症例は無効であった, 無効例はいずれもカテコラミン併用症例であった.心電図波形の比較を行ったところ, T波の波形の違いも認められ, 無効例ではTpeak-T end時間の延長が認められていた.これは, カテコラミンの作用による細胞間活動電位のばらつきによるものではないかと推測された.ニフエカラントを使用する際には, カテコラミンとの併用は行わず, 血行動態が不安定な場合には大動脈内バルーンパンピング (IABP) , 経皮的心肺補助装置 (PCPS) などの機械的サポートが有効であると考えられた.また, ニフエカラントの有効性の評価として, QT時間のみでなく陽性T波の形態 (Tpeak-Tend時間) も有効であると考えられた.

A 41-year-old man was admitted because of syncope. The electrocardiogram showed torsade de pointes (Tdp) with no long QT interval and the coupling interval of the initial beat of Tdp was 240 ms. Heterogeneity of ventricular refractoriness was observed together with shortness of the effective refractory period measured at the right ventricular inflow site where the paced QRS morphology was the same as that of the initial beat of Tdp. Verapamil could suppress frequent ventricular premature complexes with a short coupling interval, which lead to Tdp. Polymorphic ventricular tachycardia was induced by triple ventricular extrastimuli. A pure potassium channel blocker was successful in inhibiting polymorphic ventricular tachycardia inducibility by prolongation of refractoriness. These results suggested that triggered ventricular premature complexes may be represent the initiating mechanism, whereas the shortness of local refractory period and heterogeneity of ventricular refractoriness may play a role in the development and the maintenance of the Tdp.

The incidence of subacute stent thrombosis (SAT) within 30 days after stenting with a sirolimus-eluting stent (Cypher) for acute myocardial infarction (AMI) was retrospectively compared to that with bare-metal stents (BMS).Among 559 lesions in 558 consecutive AMI from April 2003 to February 2006, the incidence of documented SAT after Cypher implantation (2/276 lesions, 0.72%) was almost the same as for BMS (2 cases, 0.71%). Aspirin (81-100 mg/day) plus ticlopidine (200 mg/day) were administered continuously after admission in all 4 cases.Documented SAT did not increase after stenting with Cypher for AMI under aspirin plus ticlopidine.

Objective evaluation of the functional significance of individual stenosis in patients with multiple lesions is crucial when performing percutaneous coronary intervention (PCI). Here we propose a novel lesion-specific parameter, the epicardial resistance index (ERI), which is derived from intracoronary pressure measurements, and validate its clinical usefulness. The ERI is defined as the ratio of the resistance of an epicardial coronary stenosis to that of downstream myocardium. After obtaining intracoronary pressure data by pull-back of a 0.014″ pressure wire, the ERI was calculated as the trans-lesional pressure gradient divided by (Pd–Pv) at maximum hyperemia, where Pd = the mean distal coronary pressure in the absence of any stenosis and Pv = the central venous pressure. Using 170 measurements obtained from 75 patients, the correlation of ERI with parameters obtained from quantitative coronary angiography (QCA) and intravascular ultrasound (IVUS) was studied. ERI showed a significant correlation with the QCA-derived percent diameter stenosis (r = 0.67, P < 0.001), and with the IVUS-derived minimum luminal area (r = 0.68, P < 0.001). In 55 patients who underwent PCI with bare metal stents, a postprocedural target lesion ERI value greater than 0.16 strongly predicted the need for subsequent revascularization within six months (81% sensitivity and 80% specificity). The ERI is a useful pressure-derived hemodynamic parameter that correlates with anatomical parameters. In addition, the postprocedural resistance of the target lesion indicated by the ERI is a reliable predictor of the late outcome of PCI.

In the present study, the usefulness and feasibility of a new measuring microcatheter, the Navicath (Type-MUTO) microcatheter, for facilitating the stenting procedure subsequent to ablation using a rotablator (rota-stenting) is described. A method for measuring the length of the targeted lesion (lesion length) angiographically with the Navicath when exchanging the guide wires is presented using 2 representative cases of rota-stenting. In addition, the validity of the selected stent according to the measurement of lesion length with the Navicath was evaluated by comparing the length of the selected stent with lesion length before PCI measured by quantitative coronary angiography. Based on the results obtained, we believe the Navicath is useful for facilitating rota-stenting, and may even be applicable to PCI in general.

A 42-year-old man was treated under a diagnosis of Churg-Strauss syndrome with predonisolone pulse therapy. Three days later, he developed cardiogenic shock following acute myocardial infarction. Coronary angiography showed total occlusions in three peripheral coronary vessels. Intraaortic balloon pumping was used to maintain hemodynamics and predonisolone pulse therapy was repeated. However, he developed cardiogenic shock again after the second pulse therapy and needed percutaneous cardiopulmonary support and intraaortic balloon pumping. Accordingly, combination therapy of predonisolone and cyclophosphamide was given. He then recovered. Follow-up angiography showed recanalization of the infarct-related arteries.

We studied the anatomical structure of the isthmus between the inferior vena cava and tricuspid annulus in humans with a three-dimensional electroanatomical mapping system (CARTO, Biosense, Haifa, Israel). Fifteen patients with atrial flutter were studied. Thirteen patients had underlying heart disease. We investigated the anatomical structure of the isthmus with cross sections made from the three-dimensional right atrial map. The cross sections of the isthmus showed a concave shape in 7 patients (47%: group A), convex shape in 2 (13%: group B), and complex shape in 6 (40%: group C). The distance between the IVC and TA was 34+/-17 mm (group A), 25+/-2 mm (group B), 34+/-16 mm (group C), and 32+/-15 mm (Total), respectively. The distance between the top and bottom was 6+/-5 mm (group A), 3 mm (group B), 6+/-3 mm (group C), and 6+/-4 mm (total), respectively. Seven of 15 patients exhibited an uneven surface of more than 5 mm in depth and 4 of 15 patients had one of more than 10 mm. The anatomical structure of the isthmus varies. To carry out precise catheter ablation, these variations should be taken into consideration to ensure an effective procedure.

Nifekalant is a class III antiarrhythmic drug, which prolongs the refractory period of the atrial and ventricular myocardium, without negative inotropic action. Intravenous nifekalant was administered in four patients with atrial tachyarrhythmia and severe heart failure to terminate or prevent atrial tachyarrhythmia.Two of three episodes of atrial tachyarrhythmia were terminated by intravenous nifekalant (0.22 to 0.30 mg/kg) administration. Continuous intravenous infusion of nifekalant (0.15 to 0.40 mg/kg/hr) during six episodes to maintain the sinus rhythm, prevented recurrence of atrial tachyarrhythmia in five episodes in which prolongation of the QTc interval was observed to more than 450 msec. None of the patients showed worsening of the hemodynamics during treatment. One patient developed polymorphic ventricular tachycardia, which deteriorated into ventricular fibrillation.Nifekalant may be effective for treating atrial tachyarrhythmia in patients with severe heart failure. Further clinical studies are needed to confirm these findings.

Background The incidence of subacute stent thrombosis (SAT) within 30 days after stenting with a sirolimus-eluting stent (Cypher®) for acute myocardial infarction (AMI) was retrospectively compared to that with bare-metal stents (BMS). Methods and Results Among 559 lesions in 558 consecutive AMI from April 2003 to February 2006, the incidence of documented SAT after Cypher® implantation (2/276 lesions, 0.72%) was almost the same as for BMS (2 cases, 0.71%). Aspirin (81-100 mg/day) plus ticlopidine (200 mg/day) were administered continuously after admission in all 4 cases. Conclusion Documented SAT did not increase after stenting with Cypher ® for AMI under aspirin plus ticlopidine. (Circ J 2006; 70: 1091 - 1092)