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81.
82.
A technique is described by which a catheter is advanced from the left atrium to the left ventricle during a right heart catheterization via the leg. A loop in the catheter is created by the clockwise twisting of the catheter while it is gently pushed against the posterior left wall of the left atrium. The catheter is then pulled back and is twisted counter-clockwise. The catheter has to be soft, and biplane fluroscopy is required. During a 16-month period 162 consecutive infants and children had heart catheterization performed, during which a pediatric NIH catheter was passed to the left atrium. The loop-technique was attempted in 95 patients and was successful in 66 patients. One or two attempts were usually sufficient. No complications were encountered apart from two brief episodes of bradycardia. The technique is easy to perform with a reasonable success rate. It seems most useful in infants in whom 5F catheters are used.  相似文献   
83.
Five patients with critical aortic stenosis (aortic valve area 0.6 cm2 or less) died 2 days to 21 days following cardiac catheterization performed in anticipation of cardiac surgery. A sixth patient was successfully resuscitated for spontaneous ventricular fibrillation, and successful aortic valve replacement was accomplished. Two patients had prior history of syncope; one patient, of ventricular tachycardia; three patients, of pulmonary edema; and three patients, of crescendo angina. One patient had severe hypotension during maintenance hemodialysis for chronic renal failure. The mode of death was sudden but not witnessed in two patients. The terminal cardiac rhythms were slow junctional in one patient, idioventricular in one, ventricular tachycardia in one, and ventricular fibrillation in the fourth patient. We conclude that symptomatic patients with critical aortic stenosis should be monitored after cardiac catheterization, and surgery should be performed as soon as possible since sudden death is not unusual.  相似文献   
84.
There are few data concerning the complications and technical difficulties encountered when cardiac catheterization is performed using peripheral bypass grafts for vascular access. All cardiac catheterizations performed at our institution from January 1, 1984 to April 1, 1991 were retrospectively reviewed to assess the in-hospital clinical outcomes in patients who had arterial access for catheterization achieved via prosthetic graft puncture. Seventeen procedures had percutaneous puncture of a vascular graft from a total of 2,929 arterial catheterizations performed. The interval from graft placement to catheterization was 7.5 ± 1.1 years. Arterial sheaths were employed in all cases and corresponded to the catheter size, with 5F systems used in 53% and 7F or larger systems used in the remaining patients. No intraprocedural or postprocedural complications were recognized. Technical difficulties were limited to the inability to selectively cannulate a nondominant right coronary artery in 1 patient. We conclude that percutaneous introduction of an arterial sheath and left heart catheterization via remotely implanted vascular bypass grafts is not associated with an increased risk of procedural complications or technical difficulties. © 1993 Wiley-Liss, Inc.  相似文献   
85.
OBJECTIVES: To evaluate the role of cutting balloon angioplasty in children with pulmonary artery stenosis. BACKGROUND: Pulmonary artery stenoses can be either congenital or secondary to postoperative scar formation. Isolated multiple small-vessel pulmonary artery stenoses are very rare. No surgical procedures for their treatment are currently available. METHODS: We report on four patients in whom standard and high-pressure balloon angioplasty had failed. Three of the four (2.5-, 3-, and 3.5-years-old; two girls) had isolated multiple peripheral pulmonary artery stenosis. The fourth patient was an 11-month-old girl (8 kg) with tetralogy of Fallot and hypoplastic pulmonary artery branches treated with the implantation of two stents in the pulmonary arteries. During the follow-up this patient developed severe intrastent restenosis and showed severely hypoplasic distal left pulmonary artery. RESULTS: We treated 11 vessels. The mean vessel diameter increased by 81% (P<0.0001) and RV/LV pressure ratio decreased from 1.15 to 0.75 (P=0.05). Patient treated for intrastent restenosis underwent successful complete tetralogy of Fallot repair. None of the patients suffered procedure-related complications. At a median follow-up of 18 months, results were stable and no late complications had occurred. CONCLUSIONS: Cutting balloon angioplasty is a promising technique for the treatment of highly challenging pathologies such as small vessel pulmonary artery stenoses and intrastent restenosis.  相似文献   
86.
The initial therapy for postmyocardial infarction ventricular septal defects is surgical repair of the defect. Unfortunately, a significant number of patients develop recurrent ventricular septal defects (VSDs) following operative repair. Transcatheter closure offers an alternative to reoperation in these critically ill patients. We present a series of four patients in whom recurrent ventricular septal defects were closed using an Amplatzer VSD device.  相似文献   
87.
Reliable atrial septostomy by stenting of the atrial septum.   总被引:1,自引:0,他引:1  
The aim of this report was to describe our experience with creating an interatrial communication by stenting the interatrial septum. In many forms of congenital heart disease, the presence of an appropriate interatrial shunt is critical. After the first several weeks of life, balloon atrial septostomy is not effective, and success with other methods is limited. Clinical records, echocardiograms, and catheterization data in patients who had an atrial septal stent placed between 2001 and 2004 at UCLA were reviewed. Changes in atrial pressures and systemic saturations were analyzed. Follow-up data and explant pathology were reviewed as available. Thirteen patients had stenting of the atrial septum (four restrictive, nine nonrestrictive). In patients with elevated right and left atrial pressures, there was a mean reduction of 2.4 and 7.4 mm Hg in right atrial and left atrial pressures, respectively. In patients with transposition physiology, there was a mean increase in oxygen saturation of 11.3%. Follow-up echocardiograms revealed patent stents with excellent position relative to the atrial septum. In six cases, the stents were removed during subsequent surgery and appeared endothelialized and patent. Stenting of the atrial septum is safe and effective in selected cases, allowing for a reliable, long-lasting, restrictive or nonrestrictive interatrial communication.  相似文献   
88.
An approach has been presented for the performance of right and left heart catheterization, left ventriculography, supravalvular aortography, and coronary arteriography utilizing a #8 French, A2 multipurpose catheter. Using the manipulations described herein, the left ventricle was entered in 96% of the patients. The multipurpose catheter is an excellent catheter for left ventriculography, negating the need for catheter exchange once the left ventricle has been entered. Likewise, this catheter provides excellent supravalvular aortography and selective coronary arteriography supplemented as needed with preformed coronary arteriographic catheters. This method provides a very safe, efficient approach to the performance of complete heart catheterization in patients with clinically significant aortic stenosis.  相似文献   
89.
Urgent/emergent percutaneous transvenous mitral commissurotomy (PTMC) was performed in 10 patients (two men and eight women, aged 21 to 60 yr). All patients had arterial hypoxemia and four required mechanical respirators. PTMC was performed in the semi-recumbent position in four patients. The seven patients with pliable valves (group 1) achieved good hemodynamic and echocardiographic results after PTMC, but one died 2 wk later because of sepsis complicating preexisting pneumonitis. The two pregnant patients uneventfully delivered normal babies at term. There was continued clinical improvement in the six surviving patients at last follow-up at 11 to 39 mon (median 26). Of the three patients with calcified valves and severe subvalvular lesions (group 2), the premoribund patient in whom last-resort PTMC created severe mitral regurgitation died 3 days later of multiple organ failure. The other two patients underwent mitral valve replacement 1–6 days later because of lack of clinical improvement due to creation of severe mitral regurgitation and ineffective mitral valve dilation, respectively. In conclusion, urgent/emergent PTMC is feasible and safe. However, its outcomes are dictated by the status of diseased mitral valve and coexisting illness.  相似文献   
90.
This study aimed to investigate serum lidocaine concentrations after subcutaneous infiltration of the groin for cardiac catheterization. One hundred twenty-six patients for planned heart catheterization received five different dosages (5-25 ml) of lidocaine 2% for local anesthesia of the groin in a randomized manner. All of them received an arterial sheath and 13 received both an arterial sheath and a venous sheath for right heart catheterization. Blood samples were taken before as well as 15, 30, and 120 min after subcutaneous application of the drug. Although in 33 patients with an arterial sheath (no venous sheath) excessive doses of lidocaine 2% (20-25 ml) were used, neither symptoms of intoxication nor toxic plasma levels were observed. However, in patients receiving an additional venous sheath, toxic plasma levels were obtained in a third of the cases. One of them showed symptoms of intoxication.  相似文献   
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