Yoshiyuki Fudemoto

Specific perfusion pattern in stress 201Tl myocardial scintigraphy of left main coronary artery disease

The usefulness of stress 201Tl myocardial scintigraphy for identifying left main coronary artery disease was evaluated with data from 23 patients with 50% or more narrowing of the left main coronary artery and 56 patients with 75% or more narrowing of the major coronary arteries but without left main coronary artery involvement (no left main coronary artery disease). Quantitiative evaluation of stress perfusion scintigrams in all five patients with narrowing of the left main coronary artery of 99% or more showed a characteristic perfusion pattern (left main pattern) of extensive homogeneous defect over the whole anterolateral segment and simultaneous defects in all radii of the high anteroseptal and high posterolateral segments. On the other hand, such a perfusion pattern was noted in only 1 of 18 patients with less than 90% stenosis of the left main coronary artery and in only 1 of 56 patients with no left main coronary artery disease

Relation between the location of the infarcted area in body surface isopotential mapping and the location of myocardial infarction in vectorcardiography.

In order to examine whether our method of determining the location of the infarcted area in body surface isopotential mapping (MAP) is adequate for clinical use, a comparison was made between the location of the infarcted area using MAP and the location of myocardial infarction using vectorcardiography (VCG). The percentage of agreement between MAP and VCG in the retrospective study was 91.7% in the anterior wall, 76.7% in the lateral wall, 93.3% in the inferior wall and 73.3% in the posterior wall. The reason for the disagreement between these two methods was investigated, and criteria for determining the infarcted area using MAP and vectorcardiographic criteria for myocardial infarction were partly corrected in anterior, lateral and (high) posterior infarction to increase the clinical accuracy of both methods. Consequently, the percentage of agreement in the four walls ranged from 83.7% to 87.9%, and the diagnostic value of MAP for the infarcted area was not inferior but was more sensitive than that of VCG except in anterior infarction. In the prospective study, the same result was obtained. Secondly, in order to establish the superiority of MAP or VCG, the sensitivity and specificity of MAP and VCG to SCG (thallium-201) were calculated. Except in the anterior wall, the sensitivity of MAP to SCG was higher than that of VCG to SCG, especially in the lateral and posterior walls. Accordingly, it is suggested that MAP is the method of choice in determining the infarcted area in clinical cases.

Revaluation of the vectorcardiographic criteria in cases of myocardial infarction: A comparative study of the vectorcardiogram, the left ventriculogram and the scintigram

The results of vectorcardiograms were compared with those of the left ventriculograms and scintigrams with thallium-201 in cases of myocardial infarction to confirm the vectorcardiographic criteria of the present authors. The percentage of agreement between the VCG and scintigram was 82.5% and higher than the percentage of agreement between the VCG and the left ventriculogram. The percentage of disagreement between the negative finding in the VCG and the positive finding in the scintigram was 5.1% and consequently, a close relation was found between the VCG and scintigram. However, as the possibility of infarction was high in cases in which the scintigram finding was positive, the vectorcardiographic criteria in cases in which the VCG findings were negative were rechecked and partially corrected. Consequently the percentage of negative findings were decreased to 3.2%. Our next step was to perform the following prospective study which confirmed that the disagreement found in the corrected criteria (1.0%) was in fact less than what had been observed in the initial criteria (5.0%). Accordingly, it can be concluded that the corrected vectorcardiographic criteria in myocardial infarction may be the more reliable and useful in determining the location of the infarcted area.

New side-holed sheath for intraaortic balloon pumping to maintain limb perfusion

We developed a new side-holed shunt sheath for inserting intraaortic balloon pumps to maintain lower limb perfusion in patients with stenotic and tortuous aortoiliac arteries. This sheath has a large internal diameter and several side holes, which act as an internal shunt. It was useful and effective in 11 patients with severe aortoiliac occlusive lesions who required assistance by intraaortic balloon pumping.

Internal Shunt Sheath for IABP to Maintain the Lower Limb Perfusion.

近年, 経皮的挿入法の導入により, IABPの使用例は急増している. しかし合併症の発生は依然として多く, その対策が問題となっている. われわれはIABP留置中に腸骨動脈の狭窄や蛇行により発生する下肢血流障害に対し, 下肢血流温存を目的としたIABP用内シャントシースを開発した. 腸骨動脈に狭窄や, 蛇行を認め, 従来のIABPシステムでは下肢血流障害の発生が危惧された3例において, IABP用内シャントシースを用い良好な結果を得た. IABP用内シャントシースはIABP留置中の下肢血流温存に有用であり, またIABP留置中の下肢血流障害の病態の診断, 処置にも有用であると考えられた.

Percutaneous transluminal coronary angioplasty for multiple lesions in a coronary artery--report of two cases.

Percutaneous transluminal coronary angioplasty (PTCA) was performed successfully in two patients with angina pectoris who had two separate significant stenotic lesions in a coronary artery. One patient had stenoses in segments 6 and 7 of the left anterior descending coronary artery. After PTCA, angina disappeared, an exercise ECG became negative and a 201Tl myocardial scintigram returned to normal. In the other patient, two separate stenotic lesions were found in segment 3 of the RCA. Angina and an exercise ECG improved after PTCA. These results suggest the validity of PTCA for multiple stenotic lesions in the same coronary artery.