Coronary neovascularization and fistula formation arising from the left circumflex artery demonstrated by coronary angiography is a specific sign for the presence of left atrial appendage thrombus in patients with mitral stenosis. However, the fistula drainage site in the left atrium in relation to the thrombus cannot be ascertained by the angiographic method. We performed transesophageal echocardiography simultaneously with coronary angiography in five patients with severe mitral stenosis and left atrial appendage thrombus. The angiography showed coronary neovascularization and fistula arising from the left circumflex artery in three patients. In these three patients, the transesophageal echocardiography confirmed the presence of a coronary fistula by identifying contrast exuding from the surface of the thrombus. Thus we have shown for the first time the usefulness of contrast transesophageal echocardiography in imaging the exact drainage site of coronary artery fistula from left atrial appendage thrombus.

Aged↗

PubMedDate not supplied

Transesophageal color Doppler echocardiography during mechanical assist circulation.

Information available to determine the optimal timing for separation of patients (pts) from mechanical assist circulation (MAC) is usually limited, due to the difficulty of transfer of patients with heavy MAC systems. To evaluate the clinical efficacy of transesophageal color Doppler echocardiography (TEE) in management of patients during MAC, we examined 37 pts (32, intra-aortic balloon pumping = IABP; 4, left ventricular assist device = LVAD; 1, right VAD = RVAD) by TEE. In the other 3 pts, thoracic aneurysms (AN) (2, dissecting An; 1, true AN) were detected by TEE, which were contraindications to safe introduction of IABPs. In 29 pts on IABPs, 2 pts with LVADs, and in 1 pt with a RVAD, patients were safely weaned from MACs with confirmation of full recovery of cardiac function by TEE. However, repeat introduction of IABP support was needed in 2 pts due to severe residual mitral regurgitation, even after initial success; these became the cause of late multiple organ failure. In one pt with a LVAD, a detrimental right to left shunt through the patent foramen ovale, which resulted in severe desaturation of the arterial blood oxygenation, was detected by TEE. Left main coronary flow was measured by TEE and found to increase by 55% on IABP and by 67% on a LVAD. In conclusion, TEE is the only currently available diagnostic tool for total evaluation of cardiac function in an intensive care unit, which can provide very important information for management of patients on MACs.

Adult↗

PubMedDate not supplied

FADD gene therapy using the human telomerase catalytic subunit (hTERT) gene promoter to restrict induction of apoptosis to tumors in vitro and in vivo.

Gene transfer vectors will dramatically increase the safety and effectiveness of cancer gene therapy, if they could restrict expression of the therapeutic products to the target tumors. To realize such a tumor-targeting system, telomerase is one of the most promising candidates. It is because telomerase activity is detected in the vast majority of tumors, but not in most normal cells. Activation of telomerase is tightly regulated at the transcriptional level of the telomerase catalytic subunit (hTERT). Therefore, the use of the hTERT promoter-driven vector system could restrict the expression of therapeutic products to telomerase-positive tumors. In this study, we constructed the expression vector of FADD gene with death domain afforded by the hTERT promoter (hTERT/FADD) and investigated its effect on tumors in vitro and in vivo. Transient transfection with the hTERT/FADD construct induced apoptosis in telomerase-positive tumor cells of wide range. In contrast, normal fibroblast cells without telomerase did not undergo apoptosis following the hTERT/FADD transfer. Furthermore, the growth of subcutaneous tumors in nude mice was significantly suppressed by the intratumoral injection of the hTERT/FADD construct (every day for one week) compared to the control (P<0.0005). The findings described here indicate the high potentiality of a novel telomerase-specific gene therapy of tumors with telomerase.

Adaptor Proteins, Signal Transducing↗

PubMedDate not supplied

Effect of prostacyclin analog on pulmonary edema in isolated heart-lung autoperfusion model.

Pulmonary edema and impaired gas exchange function are worrisome early complications of heart-lung transplantation. The present study was designed to determine the effect of a new prostacyclin analog, OP-41483, on these complications with the use of a heart-lung autoperfusion model. Twenty-four mongrel puppies (4 to 6 kg) were evenly divided into four groups according to the oxygen content of inspired air (group 1, 95%; group 2, 60%) and the use of an intravenous drip of OP-41483 (0.1 microgram/kg/min) (group 3, 95% + OP; group 4, 60% + OP). During the course of these experiments, systolic pressure and cardiac output were maintained constant at 100 mm Hg and 40 ml/kg/min, respectively. Pulmonary arterial pressure was almost constant in each group throughout the experiment. Arterial oxygen tension (Pao2) was significantly decreased in groups 1 (410 +/- 49 to 237 +/- 38 mm Hg, p less than 0.01) and 2 (368 +/- 44 to 243 +/- 26 mm Hg, p less than 0.01) over the 5-hour autoperfusion period but was maintained at a high level in groups 3 (488 +/- 70 to 447 +/- 39 mm Hg) and 4 (431 +/- 33 to 430 +/- 35 mm Hg). Pathologic findings (perivascular edema and capillary dilatation) were significant in group 1 but less marked in group 2. However, no abnormal pathologic changes were observed in groups 3 or 4. These data demonstrated that OP-41483 was effective in preventing functional and pathologic pulmonary disturbances at a dosage (0.1 microgram/kg/min) that is reported to induce no undesirable hemodynamic effect.

Animals↗

PubMedDate not supplied

[Pediatric matrix biplane transesophageal echo probe: evaluation of probe selection in patients].

We have developed four different probes for the wide use of transesophageal echocardiography in children. The adult matrix biplane probe (M-BP) can generate transverse and longitudinal plane images simultaneously from a single transducer, and facilitates easier and faster understanding of the three-dimensional anatomy of the heart. This probe can be used in patients weighing more than 15 kg. The pediatric matrix biplane probe (PM-BP) has the same function as the M-BP in a smaller probe head and shaft, and can be used in patients weighing more than 5 kg. The conventional pediatric biplane probe (P-BP) with two transducers has a smaller probe head profile than the PM-BP, and can be used in a baby as small as 2.7 kg. The newborn single plane probe (N-SP) has the smallest profile with a 4 mm diameter shaft, and can be used like a nasogastric tube. We choose probes according to the size of the patient and purpose of the study. As a rule, smaller probes are less invasive and reduce the risk of the study. However, larger probes have better image quality and penetration. Proper selection of the probe is the key to the safe and effective use of this new methodology.

Child, Preschool↗

PubMedDate not supplied

[Pathological study of the transseptal puncture site of interatrial septum in catheter interventions].

Pathological changes in the transseptal puncture site of the interatrial septum were studied in seven autopsy patients in whom transseptal puncture had occurred during catheter interventions under transesophageal echocardiography monitoring. 1. In one patient with chronic renal failure who had received hemodialysis for more than 10 years, the transseptal puncture was unsuccessful. The failure is attributable to the severe calcification of the left atrial wall and interatrial septum. The autopsy showed only a small scratch on the fossa ovalis in the right atrial side. 2. The puncture hole was round in five patients and a slit in one, without tearing or extension from the puncture hole. 3. Late closure of the transseptal puncture hole was observed in two patients who died 7 and 22 days after the intervention procedures. 4. Mild infiltration of red blood cells around the transseptal puncture hole was detected in two patients. One died immediately after left atrio-arterial bypass support and another died on the 24th day after percutaneous transvenous mitral commissurotomy. Both patients showed tendency to bleeding due to heparinization and/or coagulopathy treatment during the clinical course. 5. Autopsy specimens demonstrated that the transseptal puncture was performed just on the fossa ovalis in all patients. 6. Biplanar transesophageal echocardiography is a very effective guidance method for transseptal puncture during catheter interventions.

Adult↗

PubMedDate not supplied

[Evaluation of the lumen-plaque-wall alterations by intravascular ultrasound imaging after percutaneous transluminal laser angioplasty in peripheral arteries: comparison with angiographic findings].

Intravascular ultrasound imaging was compared to angiography for evaluation of the changes in arterial lumen, atherosclerotic plaque and arterial walls after percutaneous transluminal laser angioplasty (PTLA) in peripheral arteries. Seventeen procedures using an argon laser angioplasty system (LASTAC system II) were performed in 13 patients with totally occluded lesions in the superficial femoral and iliac arteries. During or immediately after PTLA, a 30 MHz intravascular ultrasound catheter was inserted into the channel created by laser irradiation and adjunctive balloon dilatation. The outcome of PTLA was considered morphologically successful if the residual stenosis measured by intravascular ultrasound was 75% or less. Intravascular ultrasound showed eccentric plaques in 12 (71%), calcified plaques in 11 (65%), intraluminal thrombi in 2 (12%) and arterial wall injuries in 13 (76%) of the 17 lesions. PTLA was successful in 13 lesions and failed in 4. Occurrence of arterial dissections (38%) and mean residual stenoses (44 +/- 13%) were significantly (p < 0.05) lower in successful PTLA than in unsuccessful PTLA (100%, 89 +/- 3%). Eccentric stenoses, calcified plaques and arterial wall injuries were associated with poor success. Intravascular ultrasound detection of eccentric stenoses (71%), calcified plaques (65%) and arterial wall injuries (76%) was better than by angiography (29, 29, 47%). However, no significant correlation between intravascular ultrasound and angiographic findings could be found in quantitative estimation of the residual stenoses. Intraluminal thrombi were identified only by intravascular ultrasound. Angiography showed abnormalities in five (83%) of six lesions with medial injuries demonstrated by intravascular ultrasound, but none of the seven lesions with intimal injury. Intravascular ultrasound provides accurate diagnosis of eccentric stenosis, calcification, and arterial wall injury, and can quantitatively estimate residual stenosis and arterial wall injury during and immediately after PTLA in peripheral artery disease.

Aged↗