第17回日本心血管画像動態学会（2007年1月19日）口述発表抄録

心臓用3Frカテーテルの改良と造影能の評価

東北厚生年金病院　循環器センター　片平美明，菅原重生，三引義明，山中多聞，山口済，亀山剛義，菊田寿

【はじめに】本邦における診断カテーテルは，現在公称4Fr（実径4.3Fr）のシステムがひろく用いられている．より低侵襲の診断造影を目指した場合，カテーテルのdown sizingが有用であることは言うまでもない．当院では，平成15年10月からフクダ電子（株）と共同開発した3Fr診断カテーテル（実径3.4Fr）を実際の診断造影に用い，現在1,000例を越える症例に使用してきている．【問題点】現在，診断造影の約7割に3Frカテーテルを使用しているが，その95%以上は3Frカテーテルでの造影が可能である．より細い診断カテーテルを使用した場合，いくつかの問題点がある．冠動脈造影（CAG）では，冠動脈への挿入時の操作性，造影の際の保持性，造影能であり，左室造影（LVG）では，左心室へ挿入する際の操作性の問題，造影能に関するものである．【CAG用カテーテル】CAG用のカテーテルには，より高い造影能を得るために，当初より6つの側孔を設けている．これにより右冠動脈造影では，Judkins型のカテーテルで十分な造影能が得られる場合が多い．しかしながら，左冠動脈造影の場合，Judkins型のカテーテルでは，高い注入量の造影時に冠動脈からはずれることがある．このため，よりback-up性の高い形状（Vodakins型）を開発した．また，側孔の径の拡大を行い，十分な造影剤の注入量が確保できるようにした．【LVG用カテーテル】LVGでは，CAGと比較し，より高い注入速度が要求される．このため，当初より大きい内径を確保しているが，pigtail先端の安定性を改善するために側孔の径の拡大とともに側孔の数を増やす改良を行った．【結語】最終的な撮影画像の質は，注入速度，総量の適切な設定，撮影装置の性能等の複合的な要因から決定されるが，3Frカテーテルでは，良好な造影像を得るために，CAGでは0.1 ml単位の細かな注入速度のコントロールが要求され，また，LVGでは1,000 psiを越える注入圧に対応できる造影システムが不可欠といえる．しかしながら3Frカテーテルでの造影については，現状では透析患者等の特殊な症例を除いては十分な造影が可能となってきており，より低侵襲な診断造影に，3Frカテーテルが有用であるものと思われる．

The 15th Annual Meeting of JSIC (22, June 2006) poster presentation.

第15回日本心血管インターベンション学会（2006年6月22日）ポスター発表

Development and evaluation of newly designed 3-Fr catheter (Vodakins type) for left coronary angiography

Tohoku Koseinenkin Hospital, Cardiovascular Center

Yoshiaki Katahira, Shigeo Sugawara, Yoshiaki Mibiki, Tamon Yamanaka, Tasuku Yamaguchi, Takeyoshi Kameyama

[Introduction]

In Japan, 4-Fr size catheters (actually size; 4.3 Fr) are usually used for diagnostic coronary angiography. On the other hand, for percutaneous coronary intervention (PCI), the main current size of guide catheter is 6 or 7-Fr size. Furthermore, in some catheter laboratories, 5-Fr size guide catheter is used for PCI. In order to reduce invasion of diagnostic coronary angiography, smaller size catheter system is necessary. For this purpose, 3-Fr size catheters (actually size; 3.4 Fr) were developed and used in clinical cases. Now, 3-Fr size catheters had been used in over 3,000 clinical cases in Japan. In order to obtain a clear angiographic image, the high flow injection rate of contrast medium is necessary. For this purpose, newly designed 3-Fr catheters (Vodakins type, Fukuda denshi Co. Ltd, Trail HF-3F) for left coronary angiography were developed and evaluated in clinical cases. Figure 1 shows the configuration of the Vodakins and the previous designed Judkins catheters.

[Present problems]

The left coronary angiography is in need of more flow rate than right coronary angiography. Especially, in dominant left coronary, at least 3.0 ml/sec of flow rate is required. The total injection volume of 4 to 6 ml with flow rate of 2 ml/sec is sufficient to obtain a clear right coronary angiogram. On contrary, the same volume (6 ml with 2 ml/sec) as used for right coronary angiogram is often insufficient for left coronary angiogram. The simple increment of injection volume and injection rate would cause the dislodgement from left coronary ostium. Consequently, only poor angiogram could be obtained. Figure 2 shows the example of the dislodgement from left coronary ostium. Using the Judkins catheter, the simple pushing manipulation of a catheter to avoid dislodgement from coronary ostium is not efficient to stable catheter tip to the ostium. Therefore, in order to obtain the clear angiographic image, the balance between the configuration of catheter and the precise injection control of contrast medium is very important.

[Analysis of injection rate and flow volume through side-holes]

The 6 side-holes of 3-Fr catheters (figure 3) play very important roles in stabilizing the tip to coronary ostium. The flow through the side-holes decreases the flow volume through the hole of the catheter tip, which produces the counter force. This counter force could dislodge the tip from coronary ostium. The balance between the stiffness of catheter itself and the counter force produced by the flow via tip hole decides the stability of catheter tip during injection. Therefore, the precise control of injection rate and volume is required. Figure 4 shows the relationship between the injection rate via side holes and via catheter tip on conditions of the constant injection period and constant total injection volume. On condition of the constant injection period (3 sec), the flow via side-holes saturates over 2 to 3 ml/sec of injection rate. On the other hand, on condition of the constant total injection volume (6 ml), the total flow volume via side-holes decreases according to the increment of the total flow rate. Therefore, in this 3-Fr coronary angiography system, it is presumed that the appropriate zone of injection rate exists between approximately 2.0 to 2.5 ml/sec. In this analysis, it is demonstrated that the larger cross-sectional area (125 % of the previous side-hole area) of side-holes increases the flow volume and flow rate via side-holes. Using the large side-holes, more stable injection could be obtained because of decrement of the flow through the tip.

[Development of new-shape (Vodakins) catheter]

The design concepts of the Vodakins catheter (figure 1-right and 3) with 6 side holes and a softened tip are an easy engagement by Judkins-like first curve and an extra-backup force by Voda-like second curve. The injection capability of the Vodakins catheter was compared with that of the Judkins left catheter by trans-radial and femoral approach with mechanical injection system (Angiomat Illumina figure 5).

[Results and discussion]

In almost cases, Vodakins catheters were easily engaged to left coronary ostium compared with Judkins left catheters. The Judkins catheter was dislodged with pushing manipulation, while the Vodakins catheter was deeply engaged to coronary ostium. The maximum injection rates were 2.5 ml/sec with the Judkins catheter and 3.0 ml/sec with the Vodakins catheters. Figure 6 shows left coronary angiograms using a Vodakins catheter on several conditions of flow rate (2.0 ml/sec to 2.8 ml/sec) in constant total injection volume of 6 ml and a rotational angiogram. This figure shows stable position of catheter tip and clear left coronary angiography. The left coronary angiography is in need of more flow rate than right coronary angiography. Especially, in dominant left coronary, at least 3.0 ml/sec of flow rate is required. Using the newly designed Vodakins catheter, the higher flow rate and larger volume of contrast medium was obtained than that of the previous Judkins left catheter. However, the precise control of injection rate (0.1 ml/sec step) and volume is required to obtain the clear coronary angiography. Furthermore, the total image quality of angiography depends on the X-ray exposure conditions, the image process and the quality of displays. Although there are a lot of problems to deal with, such as in patients under hemodialysis, who need more injection volume of contrast medium, it is concluded that this Vodakins catheter will be useful to obtain a sufficient image quality for clinical decision.

第18回日本心血管インターベンション学会東北地方会（2005年7月23日）口述発表抄録

心臓用3Fr診断カテーテルの臨床評価

東北厚生年金病院　循環器センター　片平美明，菅原重生，三引義明，山中多聞，亀山剛義

【はじめに】本邦における診断カテーテルは，現在公称4Fr（実径4.3Fr）のシステムがひろく用いられている．より低侵襲の診断造影を目指した場合，カテーテルのdown sizingが有用であることは言うまでもない．そこで，あらたに開発した3Fr診断カテーテル（実径3.4Fr）を実際の診断造影に使用し，その評価を行った．【方法】使用したシステムは，フクダ電子（株）製の3Frカテーテル（トレールHF-3F）である．平成16年1月1日から平成17年5月16日に3Frカテーテルを用いて施行した全423症例の内，trans-radial approachで冠動脈造影（CAG）及び左室造影（LVG）を行った267症例を対象とした．CAG，LVGとも，インジェクター（Angiomat 6000）による機械注入で行い，造影能及び選択的造影をおこなう際の操作性について検討した．【結果・考察】267症例中，CAG，LVGとも3Frカテーテルで施行できたのは259例（97.0 %）で，8例（3.0 %）については4Frカテーテルまたは4Frシースへのサイズアップが必要であった．8例の内訳は，3例がradial artery及びsubclavian arteryの屈曲による操作困難例，JL（Judkins left）及びJR（Judkins right）のサイズミスマッチによる造影困難例がそれぞれ2例（合計4例），pigtail catheterによるHOCMの左室内圧格差の測定困難例1例であった．初期の133例ではオプションのカテーテルサイズ（JL3.5，JL5.0，JR5.0，LCB等）が準備できておらず，サイズミスマッチが4例と多く見られたが，オプションの形状が利用できるようになった後半の134例では，造影ができなかったのは動脈の屈曲が強いための操作困難例の2例（1.5 %）のみであった．造影が可能であった症例では，いずれも診断が充分可能な造影が得られており，より低侵襲な診断造影に，3Frカテーテルが有用であるものと考えられた．

第14回日本心血管インターベンション学会（2005年6月16日）口述発表抄録

Development and evaluation of coronary angiography system using 3-Fr catheters

東北厚生年金病院　循環器センター　片平美明，菅原重生，三引義明，山中多聞，尾添明之

[Purpose] In order to reduce invasiveness of diagnostic coronary angiography, the down sizing of catheter system is necessary. For this purpose, newly designed 3-Fr size catheters were developed and evaluated in clinical cases.

[Methods] The 3-Fr catheters (Fukuda denshi Co. Ltd, Trail HF-3F) of Judkins right (JR), Judkins left (JL) and pigtail were used in 150 clinical cases. For the more injection capacity of contrast medium, JR and JL catheters have 6 side holes and softened tip. Coronary angiography (CAG) and left ventriculography (LVG) were executed by trans-radial and trans-femoral approach with mechanical injection system (Angiomat 6000).

[Results] In almost cases, the quality of CAGs and LVGs were sufficient to diagnose coronary lesions and analyze left ventricular wall motions. The maximum injection pressures were 250-400 psi in CAG and 900-1,000 psi in LVG, respectively. In several cases of CAGs, the change of catheter type was required to engage coronary ostium and the reduction of injection rate was required to prevent disengagement. All LVGs were executed successfully with no trouble.

[Conclusion] Although higher tolerant pressure of the injection circuit, lower viscosity of the contrast medium and higher skill of operators are needed, the angiography with 3-Fr catheters has a sufficient quality for clinical decision. It is concluded that this 3-Fr catheter system will be useful to less invasive angiography.

CCT2004 (23, October 2004) poster presentation.

Development and clinical evaluation of 3-Fr catheters for coronary angiography

Cardiovascular Center, Tohoku Kosei-nenkin Hospital, Sendai, Japan

Yoshiaki Katahira, Shigeo Sugawara, Yoshiaki Mibiki, Tamon Yamanaka, Tasuku Yamaguchi

[Purpose] In Japan, 4-Fr size catheters (actually size; 4.3 Fr) are usually used for diagnostic coronary angiography. On the other hand, for percutaneous coronary intervention (PCI), the main current size of guide catheter is 7 or 6-Fr size. Furthermore, in some catheter laboratories, 5-Fr size guide catheter is used for PCI. In order to reduce invasion of diagnostic coronary angiography, smaller size catheter system is necessary. For this purpose, newly designed 3-Fr size catheters (actually size; 3.4 Fr) were developed and evaluated in clinical cases.

[Methods] The 3-Fr catheters (Fukuda denshi Co. Ltd, Trail HF-3F, Fig. 1) of JR-4, JL-4 and pigtail (length 100 cm, inner diameter 0.80 mm, maximum tolerant pressure 1,200 psi) were used in 12 clinical cases. In preliminary study using JR-4 and JL-4 catheters with two side holes, frequent disengagement from coronary ostium was observed. It was presumed that the counter force produced by the flow from the catheter tip cause the catheter to disengage from ostium. In order to prevent this disengagement and to obtain more injection capacity of contrast medium, JR-4 and JL-4 catheters have 6 side holes (Fig. 2) and softened tip. In this study, two operators who were skilled in handling 4-Fr catheters evaluated three different types of catheter tubes (torque type, hard type and middle type) into five grades according their handling without the information concerning tube types. Total 34 catheters (JR-4 12, JL-4 12, pigtail 10) were evaluated in 12 clinical cases (age 67.4 + 10.4 yrs, height 159.1 + 12.8 cm, weight 63.6 + 11.1 kg, male/female 8/4). Coronary angiography (CAG) and left ventriculography (LVG) were executed by trans-radial approach (left/right 10/2) with the mechanical injection system (Angiomat 6000) using three contrast media of Optiray 350 (ioversol, viscosity 8.2 mPa x sec), Omnipaque 350 (iohexol, viscosity 10.6 mPa x sec) and Iomelon 350 (iomeprol, viscosity 7.0 mPa x sec).

[Results] The quality of CAGs and LVGs (Fig. 3, 4 and 5) obtained in all cases were sufficient to diagnose coronary lesions and analyze left ventricular wall motions. Fig. 6 shows the radar chart about the evaluation of three-type catheter tubes. In JL-4 catheter, the torqueability and the handling of hard type were slightly higher than those of other two types. In JR-4, the injection capacity of contrast medium of hard type was slightly higher than that of other two types. On the other hand, in pigtail catheter, the handling and the injection capacity of middle type, which had the intermediate characteristics between hard and torque types, was higher than other two types. The maximum injection pressures, which were effected by the injection rate and the viscosity of contrast medium, were 254 psi in right CAG (flow rate 2.0 ml/sec, total volume 5 ml), 316 psi in left CAG (flow rate 2.5 ml/sec, total volume 7 ml) and 702 psi in LVG (flow rate 8.0 ml/sec, total volume 20 ml), respectively. No disengagement of JR-4 catheter was observed in right CAG. However, in left CAG, using higher injection rate (flow rate 2.5 ml/sec, total volume 7 ml), disengagements were observed in 5 cases (42 %). In those five cases, the reduction of the injection rate to 2.0 ml/sec in flow rate and 6 ml in total volume was necessary in order to avoid these disengagements. It was presumed that a precise adjustment of the injection rate was required to prevent disengagement of JL-4 catheter. All LVGs were executed successfully with no trouble.

[Discussion] JR-4 catheter with 6 side-holes had not only a sufficient stability up to 2.5 ml/sec in injection flow rate but also had an excellent characteristic to prevent catheter from wedging to conus branch. No disengagement from ostium was observed in right CAGs. Using 4-Fr catheters, right and left CAGs need injection rate of 2.0 to 2.5 ml/sec in flow rate and 4 to 6 ml in total volume and that of 2.0 to 3.0 ml/sec in flow rate and 5 to 8 ml in total volume, respectively. In these 3-Fr CAGs, the nearly equivalent injection rate to that of 4-Fr catheter could be available using slightly deep engagement. Consequently, the quality of right and left CAGs was sufficient to diagnose coronary lesions. The injection pressures in CAGs were 250 to 300 psi (17.0 to 20.4 atm). Therefore, manual injection is impossible in CAGs. Precisely controlled mechanical injections are necessary.

In all LVGs, pigtail catheters could be inserted to left ventricle (LV). However, in 3-Fr system, the technique of insertion to LV was slightly difficult in comparison with that in 4-Fr system. The stiff guide wire is necessary to insert pigtail catheter to LV easily. The maximum tolerant pressure in circuit, the viscosity of the contrast medium and the inner diameter of catheter have great effect upon the maximum injection rate. These 3-Fr catheters have smaller inner diameter (0.80 mm) compared with that of 4-Fr catheters. Therefore, using contrast medium of higher viscosity (10.0 to 12.0 mPa x sec), the maximum injection rate was limited to 8 ml/sec under the injection circuit with tolerant pressure of 1,000 psi (Fig. 7). However, using contrast medium of lower viscosity (10.0 to 12.0 mPa x sec), the maximum injection rate was up to 10 ml/sec under the same injection circuit. Furthermore, the lower temperature of contrast medium increases its viscosity. Therefore, the regulation of temperature of contrast medium to 35 Celsius is very important in the 3-Fr catheter system.

[Conclusion] Although higher tolerant pressure of the injection circuit, lower viscosity of the contrast medium and higher skill of operators are needed, the angiography with 3-Fr catheters has a sufficient quality for clinical decision. It is concluded that this 3-Fr catheter system will be useful to less invasive angiography.

第13回日本心血管インターベンション学会（2004年7月1日）ポスター発表抄録

冠動脈および左室造影用3Frカテーテルの開発と臨床評価

東北厚生年金病院　循環器センター　片平美明，菅原重生，三引義明，山中多聞，山口済

【はじめに】本邦における診断カテーテルは，現在公称4Fr（実径4.3Fr）のシステムがひろく用いられている．一方，PCIに使用されるガイドカテーテルは現在7から6Frのシステムが主流で，一部5Frのガイドカテーテルが使用されてきている．より低侵襲の診断造影を目指した場合，カテーテルのdown sizingが有用であることは言うまでもない．そこで，あらたに開発した3Fr診断カテーテル（実径3.4Fr）を実際の診断造影に使用し，その評価を行った．

【方法】使用したシステムは，フクダ電子（株）製の3Frカテーテル（トレールHF-3F）で，JR-4, JL-4, Pigtailの3種類を用いた．いずれもカテーテル長100 cm，内径0.80 mm，耐圧1200 psiである．冠動脈造影(CAG)及び左室造影(LVG)とも，インジェクターによる機械注入で行い，造影能及び選択的造影をおこなう際の操作性について検討した．

【結果・考察】全例trans-radial approachで評価した．CAG用のカテーテルは，始めは側孔2個のタイプを用いたが，先端からの造影剤の吹き出しによる反力により，入口部からの脱落を認めたため，側孔からの造影剤の吹き出しが優勢となるように側孔を6個に変更した．これにより，十分な注入速度が確保できたばかりでなく，RCAの造影に際し発生しやすいConus Branchへの楔入も予防することができた．また，入口部からの脱落も改善され，CAGではいずれも十分な造影結果が得られるようになった．LVGでは，カテーテルの左室への挿入が技術的にやや困難で，専用のガイドワイアーの開発が必要と思われた．また，4Frと比較して内径が小さいため，通常の粘度の造影剤では8 ml/secの注入速度が限界となるが，低粘度の最新の造影剤を使用することで，十分な左室造影の得られる10 ml/secの注入速度を得ることができ，良好な左室造影が可能であった．