Percutaneous mitral valvotomy in patients eighteen years old and younger. Immediate and late results. (1/336)

OBJECTIVE - To analyze immediate and late results of percutaneous mitral valvotomy (PMV) in patients < or = 18 year. METHODS - Between August '87 and July '97, 48 procedures were performed on 40 patients. The mean age was 15.6 years; 68.7% were females four of whom were pregnant. RESULTS - Success was obtained in 91.7% of the procedures. Immediate complications were severe mitral regurgitation (6.3%) and cardiac tamponade (2.0%). Late follow-up was obtained in 88.8% of the patients (mean value=43.2+/-33.9 months). NYHA functional class (FC) I or II was observed in 96.2% of the patients and restenosis developed in five patients, at a mean follow-up of 29.7+/-11.9 months. Three patients presented with severe mitral insufficiency and underwent surgery. Two patients died. CONCLUSION - PMV represents a valid therapeutic option in young patients. In these patients, maybe because of subclinical rheumatic activity, restenosis may have a higher incidence and occur at an earlier stage than in others persons.  (+info)

Subclavian artery disruption resulting from endovascular intervention: treatment options. (2/336)

Endovascular intervention is a commonly accepted form of treatment in patients with subclavian artery stenosis. Complications will undoubtedly occur as the utility of catheter-based intervention continues to rise. We report two cases of subclavian artery disruption as a result of endovascular intervention. One patient had contrast extravasation after the deployment of a balloon-expandable stent in a stenotic subclavian artery, and the arterial injury was successfully treated with balloon tamponade. A second patient had a large subclavian pseudoaneurysm 4 months after a balloon-expandable stent placement. Successful repair was achieved in this patient by means of arterial reconstruction with a prosthetic bypass graft. These cases illustrate different therapeutic methods of treating subclavian artery rupture due to endovascular intervention.  (+info)

Endovascular grafts and other image-guided catheter-based adjuncts to improve the treatment of ruptured aortoiliac aneurysms. (3/336)

OBJECTIVE: To report a new management approach for the treatment of ruptured aortoiliac aneurysms. METHODS: This approach includes hypotensive hemostasis, minimizing fluid resuscitation, and allowing the systolic blood pressure to fall to 50 mmHg. Under local anesthesia, a transbrachial guidewire was placed under fluoroscopic control in the supraceliac aorta. A 40-mm balloon catheter was inserted over this guidewire and inflated only if the blood pressure was less than 50 mmHg, before or after the induction of anesthesia. Fluoroscopic angiography was used to determine the suitability for endovascular graft repair. When possible, a prepared, "one-size-fits-most" endovascular aortounifemoral stented PTFE graft was used, combined with occlusion of the contralateral common iliac artery and femorofemoral bypass. If the patient's anatomy was unsuitable for endovascular graft repair, standard open repair was performed using proximal balloon control as needed. RESULTS: Twenty-five patients with ruptured aortoiliac aneurysms (18 aortic, 7 iliac) were managed using this approach. Balloon inflation for proximal control was required in nine of the 25 patients. Twenty patients were treated with endovascular grafts. Five patients required open repair. The ruptured aneurysm was excluded in all 25 patients; 23 survived. Two deaths occurred in patients who received endovascular grafts with serious comorbidities. The surviving patients who received endovascular grafts had a median hospital stay of 6 days, and the preoperative symptoms resolved in all patients. CONCLUSIONS: Hypotensive hemostasis is usually an effective means to provide time for balloon placement and often for endovascular graft insertion. With appropriate preparation and planning, many if not most patients with ruptured aneurysms can be treated by endovascular grafts. Proximal balloon control is not required often but may, when needed, be an invaluable adjunct to both endovascular graft and open repairs. The use of endovascular grafts and this approach using other image-guided catheter-based adjuncts appear to improve treatment outcomes for patients with ruptured aortoiliac aneurysms.  (+info)

Methods for assessing hepatic distending pressure and changes in hepatic capacitance in pigs. (4/336)

The equilibrium pressure obtained during simultaneous occlusion of hepatic vascular inflow and outflow was taken as the reference estimate of hepatic vascular distending pressure (P(hd)). P(hd) at baseline was 1.1 +/- 0.2 (mean +/- SE) mmHg higher than hepatic vein pressure (P(hv)) and 0.7 +/- 0.3 mmHg lower than portal vein pressure (P(pv)). Norepinephrine (NE) infusion increased P(hd) by 1. 5 +/- 0.5 mmHg and P(pv) by 3.7 +/- 0.6 mmHg but did not significantly increase P(hv). Hepatic lobar vein pressure (P(hlv)) measured by a micromanometer tipped 2-Fr catheter closely resembled P(hd) both at baseline and during NE-infusion. Dynamic pressure-volume (PV) curves were constructed from continuous measurements of P(hv) and hepatic blood volume increases (estimated by sonomicrometry) during brief occlusions of hepatic vascular outflow and compared with static PV curves constructed from P(hd) determinations at five different hepatic volumes. Estimates of hepatic vascular compliance and changes in unstressed blood volume from the two methods were in close agreement with hepatic compliance averaging 32 +/- 2 ml. mmHg(-1). kg liver(-1). NE infusion reduced unstressed blood volume by 110 +/- 38 ml/kg liver but did not alter compliance. In conclusion, P(hlv) reflects hepatic distending pressure, and the construction of dynamic PV curves is a fast and valid method for assessing hepatic compliance and changes in unstressed blood volume.  (+info)

Protein washdown as a defense mechanism against myocardial edema. (5/336)

Myocardial edema occurs in many pathological conditions. We hypothesized that protein washdown at the myocardial microvascular exchange barrier would change the distribution of interstitial proteins from large to small molecules and diminish the effect of washdown on the colloid osmotic pressure (COP) of interstitial fluid and lymph. Dogs were instrumented with coronary sinus balloon-tipped catheters and myocardial lymphatic cannulas to manipulate myocardial lymph flow and to collect lymph. Myocardial venous pressure was elevated by balloon inflation to increase transmicrovascular fluid flux and myocardial lymph flow. COP of lymph was measured directly and was also calculated from protein concentration. Decreases occurred in both protein concentration and COP of lymph. The proportion of lymph protein accounted for by albumin increased significantly, whereas that accounted for by beta-lipoprotein decreased significantly. The change in the calculated plasma-to-lymph COP gradient was significantly greater than the change in the measured COP gradient. We conclude that the change in the distribution of interstitial fluid protein species decreases the effect of protein washdown on interstitial fluid COP and limits its effectiveness as a defense mechanism against myocardial edema formation.  (+info)

Modification of a previously described arteriovenous malformation model in the swine: endovascular and combined surgical/endovascular construction and hemodynamics. (6/336)

BACKGROUND AND PURPOSE: The rete mirabile in swine has been proposed as an arteriovenous malformation (AVM) model for acute experimental studies through surgical creation of a large carotid-jugular fistula. This report describes two endovascular modifications to simplify the surgical creation and provides hemodynamic parameters for the AVM model. METHODS: An AVM model was created in 29 animals to study n-butyl 2-cyanoacrylate polymerization kinetics. The common carotid artery (CCA) was punctured and a guiding catheter was inserted tightly into the origin of the ascending pharyngeal artery (APA). The CCA was ligated proximal to the catheter to create a pressure drop across the rete, which represented the AVM nidus. The catheter hub was opened whenever needed and served as the venous drainage of the AVM nidus. The contralateral APA served as the arterial feeder. Instead of the surgical ligation of the CCA, a temporary balloon occlusion was performed in three animals. RESULTS: A mean pressure gradient of 14.9 +/- 10.5 mm Hg (range, 4-42 mm Hg) was measured across the rete. The mean flow rate was 30.4 +/- 14.2 mL/min (range, 3.5-46 mL/min), as measured at the venous drainage. CONCLUSION: The endovascular and combined surgical-endovascular rete AVM model in swine is easy to construct and is less time-consuming than are the currently used models for acute experimental studies. Hemodynamic parameters can be monitored during the entire experiment and correspond to values found in human cerebral AVMs.  (+info)

Endovascular treatment of experimental aneurysms by use of a combination of liquid embolic agents and protective devices. (7/336)

BACKGROUND AND PURPOSE: The use of liquid embolic agents for embolization of cerebral aneurysms has been reported in the neurosurgical literature. The most important limitation of this technique is the relatively poor control of migration of the liquid embolic agent into the parent artery. We performed an experimental aneurysm study using a liquid embolic agent and different protective devices to evaluate the safety and technical feasibility of this endovascular technique. METHODS: Forty lateral aneurysms were surgically constructed on 20 common carotid arteries of swine. Onyx alone was used to obliterate eight aneurysms. Onyx was also used in combination with microcoils (n = 11), microstents (n = 6), balloons inflated proximally to the neck of the aneurysm (n = 6), and across the neck of the aneurysm (n = 7). One control aneurysm was embolized with Guglielmi detachable coils (GDCs) alone. RESULTS: The use of a microballoon across the neck of the aneurysm, a microstent deployed across the neck of the aneurysm, or the deposit of GDCs into the aneurysm allowed faster and more complete filling of the aneurysm with Onyx. However, these protection devices did not totally preclude intractable migration of Onyx into the parent artery (migration rate, 9-33%). CONCLUSION: Although complete occlusion of experimental aneurysms with Onyx is feasible using protective devices, migration of the liquid embolic agent into the parent artery or intracranially remains a difficult challenge. Further experimental studies need to be performed to master this technique and to select those aneurysms that can be safely treated in clinical practice.  (+info)

Double-balloon technique for embolization of carotid cavernous fistulas. (8/336)

Embolization of a carotid cavernous fistula (CCF) by means of a detachable balloon is an established method for treating CCFs while preserving a patent parent internal carotid artery (ICA). However, failure to embolize the CCF may occur on a few occasions, such as when the balloon cannot pass through the fistula into the cavernous sinus by blood flow, or when the inflated balloon in the cavernous sinus retracts to the carotid artery. Under these circumstances, the ICA may have to be sacrificed in order to treat the CCF. Herein we describe a double-balloon technique for embolization of a CCF. By applying this technique, we successfully treated nine of 11 CCFs, without compromise of the parent ICA when the conventional one-balloon technique failed.  (+info)