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R Matsuwaka

Publications and source records attributed to R Matsuwaka.

At least 55 records · Page 3Linked to original sources
PubMed1990

[Optimal perfusion criteria for deep hypothermic selective cerebral perfusion in patients with aortic aneurysm involving aortic arch].

Although selective cerebral perfusion (SCP) might be an useful supportive method for aortic arch surgery, its optimal perfusion criteria has not been established. We studied the relationship between the oxygen saturation of superior vena cava or internal jugular vein (SvO2) and the perfusion hemodynamics during deep hypothermic (DH) SCP in twenty patients (pts) (type A dissection; 10, arch aneurysm; 10). SCP was accomplished by perfusion to the brachiocephalic trunk (BCT) and the left common carotid artery (LCC) using separate pumps. Cardiopulmonary bypass and DHSCP time were 128-312 (222 +/- 43, mean +/- SD) minutes and 25-214 (122 +/- 49) minutes, respectively. The cerebral perfusion pressures (CPP) monitored at the bilateral temporal arteries were 20-60 (47 +/- 9) mmHg and cerebral perfusion flow (CPF) was 0.28-0.7 (0.43 +/- 0.10) L/min/m2. The cerebral perfusion score (CPS) defined as CPP X CPF was 7-39 (20 +/- 8). SvO2 ranged from 79 to 99 (94 +/- 7)%. Two operative deaths were encountered from unrelated causes to SCP in both cases. Cerebral infarction occurred in one patient possibly form prolonged low perfusion with low SvO2. When the safety range of SvO2 in DHSCP was defined as greater than 90%, essential criteria to keep this range was CPP greater than 40 mmHg. In 13 out of 15 pts with SvO2 greater than 90%, CPS were above 15. In conclusion, optimal perfusion criteria for DHSCP was defined as CPP greater than 40 mmHg and CPS(CPP X CPF) greater than 15 considering adequate cerebral oxygen consumption.

Adult↗
PubMed1989

[Intraoperative echocardiographic assessment of left ventricular muscle volume changes after intracardiac operation under cardiopulmonary bypass].

Cardiopulmonary bypass (CPB) and concomitant cardioplegic arrest (CA) may cause impairment of cardiac function with development of myocardial edema. There are few reports of intraoperative assessment of LV mass or muscle volume (MV) in patients, Fifteen patients (age; 0.5-68), 10 with congenital and 5 with valvular diseases, were studied by epicardial 2-dimensional and M-mode echocardiography. LVMV was obtained from M-mode study at pre- and post-CPB during surgery. Pre and post CPB LVMV-index (ml/m2) and percent change of LVMV were compared. CPB-time was 170 +/- 78 min (mean +/- SD), and CA time was 97 +/- 49 min. LVMV index increased significantly from 89 +/- 35 to 103 +/- 43 ml/m2 after CPB (p less than 0.01). Percent change ranging from -3 to +37% (14 +/- 12) correlated to CPB time (r = .81, p less than .01) and also to CA time (r = .62, p less than .05). These results indicated that CPB with CA caused acute increase in LVMV with a positive relation to its duration.

Adolescent↗
PubMed1989

Surgery for aortic arch aneurysm with selective cerebral perfusion and hypothermic cardiopulmonary bypass.

Deep-hypothermic cardiopulmonary bypass with selective cerebral perfusion (SCP) was used in 34 consecutive patients with aneurysms involving the aortic arch or the adjacent part of the aorta. The ages ranged from 25 to 79 years (mean, 56 years). Atherosclerotic aneurysms were present in 14 patients, dissecting aortic aneurysms in 16, and other lesion types in four. Replacement of the ascending aorta was performed in 10 patients, replacement of the ascending aorta and arch in 12, replacement of the distal arch in two, and other procedures in 10. Perfusion techniques consisted of femoral artery perfusion and SCP to the brachiocephalic trunk and the left common carotid artery. The blood temperature was maintained at 16 degrees-20 degrees C. SCP time ranged from 25 to 214 minutes (mean, 123 minutes). Operative death occurred in three (9%) patients. Neurological sequelae occurred in one patient (cerebral infarction), but significant respiratory and hemorrhagic problems were not encountered. For the SCP protocols, we advise that perfusion pressures at bilateral superficial temporal arteries be kept at approximately 50 mm Hg and that venous oxygen saturation of the superior vena caval line or internal jugular vein be kept at above 90%. With appropriate monitoring, this method can be performed in aortic arch or related surgeries with low morbidity results.

Adult↗
PubMed1987

Partially unroofed coronary sinus associated with tricuspid atresia. An important associated lesion in the Fontan operation.

A case of tricuspid atresia associated with partially unroofed coronary sinus following a Fontan operation is described. A 4-year-old boy with tricuspid atresia showed persistent arterial desaturation immediately after a modified Fontan operation. At reoperation on the next day, a partially unroofed coronary sinus was recognized and repaired through a left atriotomy. Although uncommon, this associated anomaly should be kept in mind even in the absence of a persistent left superior vena cava and should be suspected if arterial desaturation occurs after a modified Fontan operation.

Child, Preschool↗
PubMed1985

[Quantitative assessment of regurgitant fraction in aortic regurgitation: comparison of two-dimensional Doppler echocardiography with other methods].

To determine proper operative procedures for aortic regurgitation (AR), we attempted to evaluate the severity of AR by two-dimensional Doppler echocardiography (TDE), using 15 mongrel dogs with experimentally-induced AR. Furthermore, the left ventricular (LV) suction method was investigated for the significance in estimating the severity of AR, cardiac outputs were measured by the thermodilution technique, TDE, and electromagnetic flowmeter (EMF). The values obtained by each method were compared. In dogs with AR, regurgitant fraction (RF) was calculated from stroke volumes obtained by TDE and EMF, as follows: RF [TDE] = (LVO-RVO)/LVO (LVO: left ventricular output; RVO: right ventricular output) RF [EMF] = [total stroke volume (T)-effective stroke volume (E)]/T The effects of alterations in afterload and pump flow rates on regurgitant fractions and regurgitant volumes measured by the LV suction method were also studied. The following results were obtained: Good correlations were observed between RVO and LVO measured by TDE, and those measured by the thermodilution technique and EMF, respectively. In dogs with AR, regurgitant fractions measured by TDE correlated well with those measured by EMF. These results strongly suggested that the Doppler index (RF) was accurate and useful for estimating the severity of AR clinically. Regurgitant volumes measured by the LV suction method were not influenced by the pump flow rate, and they correlated well with square root values of the mean diastolic pressure in the aorta. In the LV suction method, Bernoulli's theorem held good between the regurgitant volumes and the mean diastolic pressures in the aorta of the dogs with AR. Considering the factors of mean diastolic pressure in the aorta and diastolic time, regurgitant volumes measured by EMF in the beating heart showed excellent agreement with those measured by the LV suction method in ventricular fibrillation. Therefore, to evaluate quantitatively the pathophysiological changes of the aortic valve in patients with AR, we should estimate the severity of AR using regurgitant volumes corrected for the cardiac cycle at the same mean diastolic pressure in the aorta.

Animals↗
PubMed1984

Detection of left atrial thrombi in man using indium-111 labelled autologous platelets.

A scintigraphic technique using indium-111 labelled platelets to detect left atrial thrombi was used in 28 patients, 14 of whom had mitral valve disease and 14 combined valve disease. Imaging was performed in the anterior, right anterior oblique (45 degrees), and left lateral views on the day of injection and thereafter at one or two day intervals for a maximum of four days. When scintiphotos obtained in two or three views 72 or 96 hours after the platelet injection showed "hot spot areas" within the left atrial pool and indium-111 activity in these areas did not decrease with time they were interpreted as positive for thrombi. Of 28 patients, seven had positive platelet images by this criterion; of these, three underwent surgery and were found to have left atrial thrombi. One patient died, and a thrombus was found at necropsy. The remaining 21 patients had normal scintiphotos; of these, seven had no thrombi at operation and one had false negative images. The diagnostic accuracy of platelet scintigraphy by this criterion of positivity in the 12 patients in whom surgical or postmortem confirmation of thrombi could be obtained was 92%. These results indicate that this technique is a promising method for detecting active left atrial thrombi.

Adult↗
PubMedDate not supplied

Imaging analysis of platelet deposition on the extracardiac valved conduit in humans.

In 14 patients (aged 2-29 yr) with Hancock (n = 11) or Carpentier-Edwards extracardiac valved conduits (n = 3), platelet deposition (PD) was investigated using indium 111 (111In) platelet imaging. Repeated studies were performed in five patients. By visual analysis, 71% (5/7) of the imagings (7 images/5 patients) showed PD at early study 1-3 months after surgery, 9% (1/11) at intermediate study at 6-46 months (mean 21 mon) (11 images/10 patients) and 0% at late study at 81-132 months (3 images/3 patients). Quantitative analysis was made using relative ratio of radioactivity at the graft area to the area of the brachiocephalic artery (platelet accumulation index or PAI). The PAI was 1.85 +/- 0.47 (mean +/- SD) at early study, 1.51 +/- 0.23 at intermediate, and 1.36 +/- 0.37 at late study (NS). There was no significant difference in the late pressure gradients across the conduit (16-68 mon postoperatively) between the two groups with (n = 3) and without (n = 5) PD at the early stage (1-18 mon postoperatively, n = 8). The result may indicate that PD to the valved conduit in the right ventricular (RV) outflow tract occurs early postoperatively (mostly within 3 mon). The relationship of the PD detected by this method to late obstruction was not clarified in this study.

Adolescent↗
PubMedDate not supplied

A new method of assessing left ventricular function under assisted circulation using a conductance catheter.

A new method of assessing left ventricular (LV) systolic function without terminating assisted circulation (AC) was investigated using a LV volume catheter (conductance catheter) in canine cardiopulmonary bypass (CPB) (Group 1, n = 7) and left heart bypass (LHB) (Group 2, n = 5) models. The hearts were subjected to either 20 min of global ischemia (IS), with a subsequent 80 min of reperfusion under CPB, or regional IS under LHB. Instantaneous LV pressure-volume data acquisitions were repeated during transient (15 sec) acute volume loading without terminating bypass. The relationship between the stroke work (SW), determined as the area of the pressure-volume loop, and the end-diastolic volume (EDV), were highly linear at every study point (mean: r = 0.956-0.986 in Group 1, r = 0.974-0.987 in Group 2). The slopes of SW and EDV (preload recruitable stroke work: PRSW) significantly decreased after IS, in both Group 1 and Group 2. In conclusion, measurement of PRSW without terminating bypass seemed to be useful in evaluating LV systolic function in patients under AC.

Animals↗
PubMedDate not supplied

Evaluation of the biocompatibility of a new method for heparin coating of a cardiopulmonary bypass circuit.

The biocompatibility of the Terumo (Terumo Corporation, Tokyo, Japan) covalent heparin coating method in a cardiopulmonary bypass (CPB) circuit was evaluated in ex vivo and in vivo experiments. In the ex vivo experiment, fresh human heparinized blood primed both a miniature heparin coated circuit (HCC) and the identical noncoated circuit (NCC), and was circulated simultaneously for 2 hr (n = 6). In the in vivo experiment, 10 rabbits underwent 2 hr of CPB under systemic heparinization (ACT > 400 sec) with HCC (n = 5) and with NCC (n = 5). In the ex vivo study, thrombin/anti-thrombin III complex, thromboglobulin, platelet factor IV, granulocyte elastase, and C3a were significantly lower in the HCC than in the NCC at 60 and 120 min of circulation (p < 0.05). In the in vivo study, platelet counts (percent of value at 10 min of CPB) were significantly higher in the HCC than NCC (HCC:NCC 87 +/- 10:71 +/- 12 at 60 min, 81 +/- 17:56 +/- 16 at 120 min). Scanning electron microscopic examination of the circuits showed less significant adhesion and pseudopod formation of platelets in the HCC than NCC in both ex vivo and in vivo situations. These results demonstrate that this heparin coated CPB circuit provides superior biocompatibility compared with a noncoated circuit by reducing the activation of the coagulation cascade, platelets, leukocytes, and complement.

Animals↗
PubMedDate not supplied

Improved management of selective cerebral perfusion in aortic arch surgery.

To establish a safe and reliable method for cerebral protection in aortic arch surgery, the authors attempted antegrade selective cerebral perfusion (SCP) based on the characteristics of jugular venous oxygen saturation (SjO2). Twenty patients were divided into two groups: a control group and SCP group. In the control group, in 13 adult patients undergoing cardiac surgery using standard hypothermic cardiopulmonary bypass, the relationship between SjO2 and nasopharyngeal temperature (NPT) during rewarming showed an inverse linear correlation:SjO2 = -2.3 NPT + 133 (r = 0.616). In the SCP group, seven patients with aortic arch aneurysm underwent surgery using SCP performed through direct cannulation of the innominate and left carotid arteries. While on SCP (83 +/- 24 min), the blood was warmed from 28 to 36 degrees C. Cerebral perfusion pressure of 40-60 mm Hg was necessary to maintain the SjO2 equal to the value in the control group at each NPT during SCP in all seven patients. None of the patients had any post operative complications. Our experience suggests that SCP can be safely performed at both mild hypothermia and normothermia under monitoring of perfusion pressure and SjO2 in aortic arch surgery.

Adult↗
PubMedDate not supplied

Initial experience with cool head, warm body perfusion in aortic arch surgery.

BACKGROUND: Hypothermia has been an essential technique in aortic arch surgery for protecting the brain. To reduce the adverse effect caused by hypothermia, we modified the perfusion technique in aortic arch surgery. Initial results using this modified technique are reviewed. METHODS: Nineteen patients were operated on for aortic aneurysm involving the aortic arch. Fifteen patients had nondissecting aneurysm and four patients had type A dissecting aneurysm including three with acute dissection. While on the hypothermic (25 degrees C to 28 degrees C of nasopharyngeal temperature) antegrade selective cerebral perfusion (SCP) was performed by direct cannulation to the brachiocephalic and left common carotid arteries, visceral perfusion via the femoral artery or graft was performed with tepid or normothermia (34 degrees C to 36 degrees C). RESULTS: Hospital mortality rate was 5.3% (1/19 patients). None of the 19 patients suffered from stroke postoperatively. Duration of total cardiopulmonary bypass and SCP was 144 +/- 36 minutes and 90 +/- 34 minutes, respectively. Eighteen surviving patients were extubated at 9.4 +/- 13.2 hours and stayed in the intensive care unit (ICU) for 3.0 +/- 1.8 days after the surgery. CONCLUSIONS: Our initial experience revealed that the modified technique using simultaneous hypothermic cerebral perfusion and tepid or normothermic visceral perfusion can be a useful adjunct during aortic arch surgery providing quick recovery.

Aged↗