Search PubMed⌕ Search

Biomedical subjects

K H Barth

Publications and source records attributed to K H Barth.

At least 55 records · Page 3Linked to original sources
PubMed1983

Pulmonary arteriovenous malformations. Physiologic observations and results of therapeutic balloon embolization.

Pulmonary arteriovenous malformations can result in severe hypoxemia and dyspnea. We measured pulmonary function, arterial blood gases, and hemodynamics in 10 patients with such malformations. Pulmonary-function tests were normal, but hypoxemia was associated with chronic hyperventilation at rest (mean, 12 liters per minute; mean carbon dioxide tension, 28 mm Hg). With exercise, ventilation increased more than expected for the level of carbon dioxide production. Balloon embolization of 58 of the 71 visible vascular malformations in the 10 patients resulted in an increase in arterial oxygen tension (43 vs. 64 mm Hg; P less than 0.001) and hemoglobin saturation (79 vs. 92 per cent; P less than 0.001). Nine patients had improved exercise tolerance. Forty-eight to 72 hours after correction of the hypoxemia, resting ventilation had decreased but was still above normal (mean, 9.3 liters per minutes; mean carbon dioxide tension, 29 mm Hg). We conclude that ventilatory responses in these patients are similar to those of people from sea-level areas who are acclimated to high altitudes and that dyspnea is due to inappropriately high levels of ventilation for a given workload under hypoxic conditions.

Adult↗
PubMed1983

Therapeutic embolization of the kidney with detachable silicone balloons.

Detachable silicone balloons were used for therapeutic renal artery embolization in 14 patients. Hematuria was controlled by occlusion of the arteriovenous fistulas in 6 patients and aneurysms in 3. The method was used for preoperative occlusion of the renal artery in 4 patients with renal cell carcinoma and for renal ablation in an attempt to cure hypertension in 1 additional patient. Detachable silicone balloons offer a safe and precise method for the occlusion of traumatic arteriovenous fistulas and aneurysms of the renal artery branches. Although balloon embolization also can be applied to the preoperative occlusion of renal neoplasms the conventional embolization techniques using absorbable gelatin sponge and coils are equally effective with less expense. No complications were observed in our 14 patients.

Adenocarcinoma↗
PubMed1983

Mechanisms of recurrent varicocele after balloon occlusion or surgical ligation of the internal spermatic vein.

Clinical recurrence of varicocele developed in eight of 70 patients (11%) who underwent balloon occlusion of the internal spermatic vein (ISV) at the level of the third or fourth lumbar vertebra. Five patients also underwent venography for postoperative recurrence of varicocele. Recurrence was due to either collateral veins that bypassed the balloon occlusion or surgical ligation. The ISV was reconstituted in the pelvis of five of the eight patients following balloon occlusion, and in all patients following surgical ligation. Two patients who had recurrence after balloon embolization had clinically undetected right sided varicoceles. The technique of balloon occlusion of the spermatic vein should be modified: in most cases the balloon should be placed in the inguinal segment of the vein below the point where the collateral veins enter the ISV. The best site for balloon detachment can be determined by test occlusion and ISV venography to observe for blood flow within the collateral veins beyond the balloon. Venography is performed prior to detachment, and if the anatomy suggests a likely recurrence, the position of the balloon is shifted, which offers an advantage over other methods of treatment.

Catheterization↗
PubMed1983

Angioarchitecture of pulmonary arteriovenous malformations: an important consideration before embolotherapy.

Seventeen patients with 91 pulmonary arteriovenous malformations were evaluated by superselective angiography. Seventy-two (79%) of the malformations consisted of a simple type characterized by a single feeding artery draining into a bulbous, nonseptated aneurysmal communication with a single draining vein. The other 19 (21%) were complex, consisting of two or more pulmonary artery branches communicating with a bulbous septated aneurysmal part with two or more draining veins. Two patients had diffuse pulmonary arteriovenous malformations confined to multiple lobes of the lung. Balloon embolotherapy was effective in permanently obliterating the malformations in 14 patients treated. Therapy provided a sustained rise in arterial PO2 in the sitting position from a mean value of 44 mm Hg before occlusion to 65 mm Hg after occlusion. In three patients the process was too diffuse and/or the malformations too large for therapy to be effective. Complex pulmonary arteriovenous malformations required occlusion of all feeding arteries. Balloon embolotherapy provided an effective treatment for pulmonary arteriovenous malformations regardless of anatomic type.

Adolescent↗
PubMed1983

Ruptured lumbar artery pseudoaneurysm: an unusual cause of retroperitoneal hemorrhage.

A patient with a functioning renal transplant presented for treatment 8 years after operation with acute retroperitoneal hemorrhage ipsilateral to the allograft. A ruptured false aneurysm of the lumbar artery was identified and was treated initially with balloon catheter occlusion, then operative ligation, with satisfactory result.

Abdominal Muscles↗
PubMed1983

Long-term results of aortoiliac angioplasty.

Results of percutaneous transluminal angioplasty of 141 iliac arteries in 112 patients are reported, with a follow-up period extending to 36 months. Initial technical success was achieved in 95.7%, 1-year patency in 91.3%, and accumulated 2- and 3-year patency in 89%. The role of outflow disease and ankle:arm index measurement and the importance of eliminating or significantly reducing the intra-arterial pressure gradients are discussed.

Adult↗
PubMed1982

Percutaneous transluminal angioplasty as an adjunct to the surgical management of peripheral vascular disease.

Percutaneous transluminal angioplasty (PTA) was performed as an adjunct to an operation in 43 patients with peripheral arterial insufficiency. This represents 26% of patients undergoing PTA over the past 44 months. In 23 patients PTA was done in conjunction with planned vascular reconstruction. It was successful in all 23 patients, and patency of the vascular graft was maintained in 22 patients during a mean follow-up period of nine months. Fourteen patients had PTA after operation. It was successful in 13 of them, and vascular patency was maintained in all 13 during a mean follow-up period of four months. Six patients had PTA prior to a distal amputation or a skin graft. All healed promptly. The overall initial success rate of PTA was 98%, the complication rate was 2%, with a late failure rate of 2%. It is concluded that PTA is a valuable adjunct to vascular surgery to improve inflow or outflow for bypass grafts, to reduce the extent of the operation in poor risk patients, to facilitate the healing of distal amputations, and to manage late graft stenosis.

Adult↗
PubMed1982

Hemodynamic measurements in the evaluation and follow-up of transluminal angioplasty of the iliac and femoral arteries.

Intra-arterial pressure measurements and ankle pressure indices (determined by Doppler ultrasound) were used to evaluate the hemodynamic response after transluminal angioplasty of the iliac and superficial femoral arteries. Intra-arterial pressure was the best determinant of the end point and technical success of the procedure, while improvement in the ankle pressure index was a good predictor of clinical success. Patients with clinical improvement had a significant increase in ankle pressure regardless of the status of peripheral runoff, while those without improvement did not; they demonstrated impaired distal runoff and required further surgical intervention. Peripheral Doppler pressures also provided a convenient noninvasive method of long-term follow-up.

Angioplasty, Balloon↗
PubMed1982

Embolotherapy of pulmonary arteriovenous malformations with detachable balloons.

Multiple pulmonary arteriovenous malformations (PAVM) present a difficult management problem, since surgical resection is not feasible in most instances. Embolotherapy offers a viable alternative. Over a 2-year period, the authors used detachable balloons to treat 16 PAVMs in 5 patients, of whom 4 had severe hypoxemia and 1 had hemoptysis. Symptomatic improvement was achieved in all but 1 patient, in whom the largest PAVM could not be occluded because the balloon was too small. Two patients exhibited segmental pulmonary infarctions. Follow-up angiograms 4 months and 2 years after occlusion demonstrated persistent obliteration of 14 PAVMs without development of collateral supply; 2 required re-embolization due to enlargement of existing nonoccluded feeders. The authors feel that balloon embolization is a safe and effective treatment of PAVMs.

Adult↗
PubMed1982

Percutaneous biliary drainage in the management of biliary sepsis.

Percutaneous biliary drainage was performed in 18 patients with biliary sepsis due to acute obstructive cholangitis and postoperative complications. Internal drainage could be established in 78% of patients, and 22% were managed on external drainage. Nine patients were managed on long-term internal drainage, six underwent uneventful surgery after successful percutaneous decompression, and three died as a result of septic shock. Percutaneous biliary drainage procedures can be lifesaving in biliary sepsis. Once infection and the hyperbilirubinemia are controlled, rational therapy plans can be formulated on the basis of the anatomy and natural history of the underlying disease.

Aged↗
PubMed1981

Quantification of arteriovenous shunting in renal cell carcinoma.

Arteriovenous shunting was quantitated with 20 plus or minus 10 mu 99mtechnetium human albumin microspheres in 12 patients with angiographically hypervascular renal cell carcinomas. Arteriovenous shunting was diagnosed angiographically when the renal vein was opacified during the arterial phase. With use of an angiographic catheter 2 to 3 mCi. 99mtechnetium human albumin microspheres were first injected into the renal artery directly supplying the tumor. Thereafter, 0.5 to 1 mCi. microspheres were injected into the inferior vena cava. Scintillation counts over the right lung were obtained immediately after each injection. The ratio between the 2 counts established the rate of tumor shunting after correction for dose difference and decay. Nine patients without angiographic evidence of arteriovenous shunting had mean shunt rates of 15 per cent, whereas 3 patients with angiographically visible shunting had significantly higher shunt rates of 57 per cent (p less than 0.001). It is concluded that angiography discovers only massive arteriovenous shunting in patients with renal cell carcinoma, whereas a fair degree of arteriovenous shunting may go undetected. The significance of minimal or moderate arteriovenous shunting in patients with renal cell carcinoma needs further investigation. The microsphere quantitation method can be applied routinely to angiography.

Adenocarcinoma↗
PubMed1981

Renal venous renin sampling. Prospective study of technique and methods.

During a three-year period, 107 patients undergoing renal arteriography were studied to evaluate the influence of renin sampling techniques and contrast material administration on renal venous renin activity. Plasma renin activity was nearly equal in three extrarenal sampling sites (antecubital vein, aorta, and lower inferior vena cava). Values for renal vein renin activity obtained with a single catheter (nonsimultaneous sampling) did not differ significantly from those obtained with two catheters (simultaneous sampling). Similarly, contrast material had no significant effect on renal vein renin activity levels. Thus, in hypertensive patients, sampling for renal venous renin activity can be performed accurately with a single venous catheter after renovascular disease has been demonstrated by arteriography.

Blood Specimen Collection↗
PubMed1981

Occlusion of varicoceles wih detachable balloons.

Fifty-two varicoceles in 50 outpatients were treated by occlusion of the internal spermatic vein (ISV) using detachable balloons 1-2 mm in diameter. The primary reason for treatment was pain in 7 patients and subfertility in 43. All achieved satisfactory occlusion, and only one recurrence was noted in 8 months of follow-up. Limited pre-occlusion venograms allowed precise balloon placement relative to collateral veins which could cause recurrence. This is a safe and effective nonsurgical method of obliterating varicoceles in outpatients.

Catheterization↗