Tatsuki Katsumura

Comparison of blood-flow velocity waveforms in different coronary artery bypass grafts. Sequential saphenous vein grafts and internal mammary artery grafts.

Characteristics of blood-flow velocities were investigated at different sites in two types of coronary artery bypass grafts, sequential saphenous vein grafts (SSVG) and internal mammary artery grafts (IMAG). The latter appear to have the longest life span. The patency rate of the side-to-side anastomosis of the SSVG is better than that of the end-to-side anastomosis. The SSVG was anastomosed to the major diagonal branch by side-to-side anastomosis and to the left anterior descending coronary artery (LAD) by end-to-side anastomosis in 13 patients who had 75-100% and 75-90% stenoses in the LAD and major diagonal branch, respectively. IMAG anastomoses were performed to the LAD in 10 patients with 75-100% stenoses of the artery. The blood-flow velocities were measured by the 20-MHz, eighty-channel ultrasound pulsed Doppler method during surgery. In six patients in the SSVG group, we investigated the configuration of velocity profiles at the region just proximal to the side-to-side anastomosis and at the bridge portion between the side-to-side and end-to-side anastomosis. In the other seven patients, we measured the blood-flow velocity at several centimeters proximal to the side-to-side anastomosis and compared it with that in the IMAG. At the region just proximal to the side-to-side anastomosis, the velocity profile skewed toward the anastomosis side wall in all patients, and the flow velocity near the wall opposite to the side-to-side anastomosis was reversed in five of six patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Therapeutic Effect of Ticlopidine, a New Inhibitor of Platelet Aggregation, on Chronic Arterial Occlusive Diseases, a Double-blind Study versus Placebo

The clinical efficacy of ticlopidine, a platelet aggregation inhibitor, was evaluated in a double-blind placebo-controlled study on 193 patients with ischemic ulcers due to chronic arterial occlusion. In the group treated with ticlopidine, significantly better efficacy was noted over the placebo group in terms of judgment on overall improvement by doctors in charge as well as by the committee assessing with color slide films. The drug was particularly effective for the treatment of patients with occlusion in the arteries on the distal side and for the ischemic ulcer with relatively small size. In the group with ticlopidine, granulation was significantly improved compared to the placebo group. Those patients who had pain due to arterial occlusion on the distal side were significantly improved by this agent. The mean diameters of ulcers were clearly reduced. Therefore, this agent could possibly be claimed as an effective remedy against the main symptoms of chronic arterial occlu sion. The frequencies of side effects and abnormalities in laboratory tests were comparable in the group treated with ticlopidine to those of the group with placebo. It was, therefore, concluded that this agent has an outstanding clinical value as a conservative treatment in chronic arterial occlusion.

Coronary Flow Velocity Waveforms in Aortic Stenosis and the Effects of Valve Replacement

In 6 patients with pure aortic stenosis, the flow velocity waveforms in the left anterior descending coronary artery were studied using an 80-channel 20-MHz pulsed Doppler velocimeter before and immediately after aortic valve replacement. All patients showed normal coronary arteriograms. The left anterior descending coronary artery flow velocity waveform in aortic stenosis was characterized by a reverse flow in the first half of systole and a slowly increasing diastolic inflow. After aortic valve replacement, the reverse flow in the first half of systole disappeared in all patients, but an end-systolic reverse flow was discerned in 5 of 6 patients. The increasing rate of the diastolic inflow was augmented in all patients. After aortic valve replacement, the time from onset of diastole to the diastolic peak velocity was shortened from 176.8 +/- 28.8 to 90.5 +/- 18.8 ms (p less than 0.01), and the diastolic peak velocity increased from 90.5 +/- 28.0 to 122.5 +/- 17.2 cm/s (p less than 0.05). Blood pressure and heart rate, however, did not change significantly before and after valve replacement. These changes in the left coronary artery velocity waveforms after valve replacement suggest the beneficial effects of removal of aortic stenosis on human coronary artery inflow.

The Entity of Buerger's Disease

It is generally believed until a decade ago that there are two types of chronic arterial occlusive disease of the extremities: Buerger’s disease and arteriosclerosis obliterans. However, recently, Buerger’s disease has been attacked from the clinicopathological view point and its existence as an entity is highly suspected in Western countries. The senior author’in 1964 discussed this problem based on experiences with these diseases in Japan and pointed out there are distinct differences in several respect in the two diseases. Since then, experiences with reconstructive surgery on patients in both diseases have increased and further information to confirm the previous conclusion have been obtained. The purpose of this paper is to discuss the entity of Buerger’s disease based mainly

Coronary flow characteristics of left coronary artery in aortic regurgitation before and after aortic valve replacement

In 6 patients with pure aortic regurgitation, the velocity waveform in the left anterior descending coronary artery (LAD) was measured using an 80-channel 20-MHz-pulse Doppler velocimeter before and immediately after aortic valve replacement. All patients showed normal coronary angiograms. Flow velocity was analyzed by both zero-cross and fast Fourier transform methods in real time. The LAD flow in severe aortic regurgitation was characterized by an increase in the systolic flow component, a small and rapidly decreased diastolic flow, an irregular velocity profile across the vessel, and a wider velocity spectrum. After aortic valve replacement, systolic flow decreased by 36.3 +/- 21.7% (p less than 0.01), whereas diastolic flow increased by 81.4 +/- 51.8% (p less than 0.05). The ratio of diastolic flow to total LAD flow increased from 63 +/- 13% to 82 +/- 7% (p less than 0.05). The velocity profile became more parabolic and had a narrow spectrum. These results suggest that operation for aortic regurgitation induces beneficial effects on the myocardial inflow immediately after valve replacement.

Thallium-201 imaging with color display computer system in old myocardial infarction

In 13 patients with old myocardial infarction diagnosed with use of the electrocardiogram, coronary angiogram and left ventriculogram and in 11 patients without infarction, thallium-201 imaging with a color display computer system was carried out. In the group without infarction the average ratio of activities in two regions of interest within the myocardial wall, excluding the apex, was 1.14 (1.08 to 1.23). In the group with infarction the average ratio of noninfarcted to infarcted areas was 1.44 (1.23 to 1.78). Objective detection of infarction was possible in 12 patients (92 percent) in the group with infarction. In two patients, the earlier electrocardiographic pattern of infarction had resolved by the time of imaging. These results suggest that the sensitivity of thallium-201 imaging in the diagnosis of old myocardial infarction may be greatly enhanced by objective and quantitative analysis using a color display computer system.

Antiphospholipid antibody syndrome and vasoocclusive diseases

One hundred and thirty-four patients with vasoocclusive diseases were retrospectively tested for three kinds of antiphospholipid antibody (aPL). The mean age at onset of the disease in 58 patients with aPL was 43 years old. Seventeen, 11, and 9 patients were positive for the aCL IgA, IgM, and IgG isotypes, respectively. The rates of anti-phospholipid syndrome (APS) in patients with arterial (n=94), venous (n= 31), or both arterial and venous (n=9) occlusion were 45%, 29%, and 78%, respectively.The rates of APS in patients with autoimmune disease (n=13), thromboangiitis obliterans (TAO) (n= 36), arteriosclerosis obliterans (ASO) with lower leg involvement (n=8) or aortic arch syndrome (n=5), Raynauds syndrome (n=15), aortitis syndrome (n= 13), ischemic heart disease (IHD) with young onset (n =12), and bilateral leg deep venous thrombosis (DVT) (n=10) were 77%, 46%, 13%, 80%, 40%, 62%, 33%, and 70%, respectively. The cumulative patency rate for reconstructive surgery in patients (n=13) with aCL was found to be considerably lower than that in those without aCL (n=13). From these results it was concluded that IgA was the most valuable aCL isotype for the diagnosis of APS and that aPL should be examined in patients with double-vessel occlusion, autoimmune disease, bilateral leg DVT, aortic arch syndrome, TAO, Raynauds syndrome, or IHD with young onset. Furthermore, prophylaxis for graft failure is more strongly recommended for patients with aCL than for those without it.

Significance of Distal Runoff and Concomitant Lumbar Sympathectomy in Bypass Surgery for Patients with Thromboangiitis Obliterans

The graft patency of bypass surgery to or distal to the popliteal artery for 29 lower extremities with thromboangiitis obliterans (TAO) and for 67 lower ex tremities with arteriosclerosis obliterans (ASO) and six factors influencing graft patency were studied and a new method of scoring distal runoff determined from angiographic findings was employed. Early graft occlusion (EGO, < one month) was found only in lower extremi ties with distal runoff of 5 or less and more frequently in patients with TAO than in those with ASO, although distal runoff in TAO patients (n=29) was signifi cantly less than that in ASO. Among TAO patients with distal runoff of 5 or less, EGO (n = 7) was found only in those without concomitant lumbar sympathectomy (CLS), but the dif ference in distal runoff between patients with EGO and those without it was not significant. From these results, it was concluded that: (1) EGO in patients with TAO is probably due to poor distal runoff with high constrictivity and (2) CLS for such patients could improve EGO, which, in turn, would result in a better cumula tive patency rate.

Characteristics of Coronary Artery Blood Velocity Waveforms in Aortic Stenosis and Regurgitation

In twelve adult patients with pure aortic stenosis (AS) and pure aortic regurgitation (AR), we measured blood velocity waveforms in the left anterior descending coronary artery (LAD) before cardiopulmonary bypass and after aortic valve replacement. The coronary artery blood velocity waveform in AS was characterized by: (1) a decreased systolic velocity component (frequently reversed) and (2) a slowly increasing rate of diastolic inflow. On the other hand, the characteristics of the velocity waveform in AR were: (1) a relatively large systolic velocity component and (2) a rapidly decreasing diastolic flow wave. After valve replacement both for AS and AR, the velocity waveform returned to an almost normal pattern, indicating that the valve replacement induces beneficial effects on the myocardial inflow.

Non-Penetrating Traumatic Tricuspid Regurgitation after Mitral Valve Replacement

A case of traumatic rupture of the tricuspid chordae tendineae with severe regurgitation in a patient who previously had mitral valve replacement is presented. In this case, it is strongly suggested that a firm pericardial adhesion of the anterior right ventricular wall became a factor of the disruption of the tricuspid valve under a slight precordial blow.