Search PubMed⌕ Search

Biomedical subjects

T A Sos

Publications and source records attributed to T A Sos.

At least 55 records · Page 3Linked to original sources
PubMed1984

Role of balloon dilatation in the treatment of renovascular hypertension.

Renal angioplasty is now well established as a treatment for renovascular hypertension. In patients with fibromuscular dysplasia, the technique is usually technically successful, and the therapeutic effect on blood pressure is as good as with surgical revascularization. In patients with atheroma, the success rate is lower, mainly because of technical problems associated with inability to pass the catheter across the stenosis. In patients in whom this can be done, the results are similar to those of surgery. In our experience, the rate of restenosis is acceptably low, and in most patients, improvement has been maintained over two years. Selection of suitable patients is based on screening from the clinical history and examination, combined with renin-sodium profiling. Renal vein renin measurements have been found reliably to predict the therapeutic outcome of angioplasty, and the incremental method of Vaughan has been preferable to use of the ratio between the two renal veins. In patients with high renin-sodium profiles or in those with normal profiles and a clinical suspicion of renovascular hypertension, renal vein renin values would be determined next, usually with digital intravenous angioplasty. A single test dose of captopril may also be useful as a screening test. If these procedures do indicate the presence of renovascular hypertension, the patient is admitted to the hospital, and arteriography and angioplasty are performed at the same session.

Angioplasty, Balloon↗
PubMed1984

Two cases of spontaneous lysis of arterial thrombi.

Two cases of spontaneous lysis of arterial thrombi are described. The occurrence of spontaneous thrombolysis and the relative ease of performing Fogarty embolectomy (thrombectomy) in peripheral arteries should be considered along with the clinical status of a patient who is viewed as a possible candidate for thrombolytic therapy, a procedure which has a potential for severe hemorrhagic complications.

Adolescent↗
PubMed1984

Predictive value and changes of renin secretion in hypertensive patients with unilateral renovascular disease undergoing successful renal angioplasty.

Peripheral and renal vein renin activity was measured in 46 hypertensive patients with arteriographically diagnosed unilateral renal artery stenosis before and six months after technically successful renal angioplasty. The renin-sodium profile was high in 80 percent before angioplasty, fell in all patients, and became normal or low in 85 percent after angioplasty. Renal vein renin activity, which initially showed lateralization of renin secretion to the ischemic kidney with contralateral suppression, became normal. Renal vein renin activity was more reliable for predicting the therapeutic response when expressed as the increment of renin for each renal vein over the infrarenal vena caval value (sensitivity 74 percent, specificity 100 percent) than as the ratio between the two renal veins (sensitivity 62 percent, specificity 60 percent). The predictive value of renal vein renin activity is poor when plasma renin activity is stimulated by long-term administration of captopril. These data support the usefulness and define the limitations of peripheral and renal vein renin measurements in selecting patients for treatment by renal angioplasty.

Adult↗
PubMed1984

Percutaneous embolectomy by transcatheter aspiration. Work in progress.

Distal embolization occurred in 14 of 339 (4%) attempted percutaneous transluminal angioplasty (PTA) procedures, including five of 225 stenoses (2.2%) and nine of the 81 occlusions (11%) that were crossed successfully in 114 attempts (8%). Transcatheter embolectomy by aspiration through a nontapered large-bore catheter was technically successful in five of six attempts (83%), and was combined with successful PTA in three of five patients. In two patients in whom the clinical result of PTA was considered unsatisfactory, successful transcatheter embolectomy permitted an uncomplicated surgical by-pass procedure to be performed. If clinically significant embolization occurs during PTA, this procedure can be attempted prior to surgical embolectomy as an alternative to local fibrinolytic therapy.

Aged↗
PubMed1984

Optimal injection technique for intravenous digital subtraction angiography. Animal and clinical studies of right atrial injection using small volumes (25 ml) at a high rate (35 ml/sec).

Small-volume right atrial injections of contrast material (25 ml) delivered at a high rate (30-35 ml) were routinely performed for digital subtraction angiography in 232 studies (698 injections). Excellent opacification of the aorta and peripheral arteries was consistently obtained. Superior opacification following right atrial injections compared with peripheral or superior vena cava boluses was confirmed in animal experiments.

Angiography↗
PubMed1984

Clinical evaluation of renovascular hypertension and therapeutic decisions.

The renal arteriogram alone, useful as an anatomic guide for the surgeon or radiologist, is inadequate to predict potential blood pressure reversal by correction of the obstructing lesion. A patient must be identified as having functionally significant renal arterial disease before intervention can be recommended. The authors discuss uncovering functionally significant renal artery stenosis, the pathophysiology of experimental Goldblatt hypertension, and criteria to identify renovascular hypertension, including peripheral plasma renin activity and differential renal-vein renin determinations.

Adult↗
PubMed1984

The current role of renal angioplasty in the treatment of renovascular hypertension.

Percutaneous transluminal renal angioplasty, a relatively noninvasive technique, has assumed an increasing role in the treatment of renovascular hypertension. The combined advent of digital subtraction angiography, renal-vein renin samples, and percutaneous transluminal angioplasty have prompted many physicians to reassess their treatment strategies. The authors present their experience with renal angioplasty at the New York Hospital and briefly describe the history and mechanism of action of this procedure.

Adult↗
PubMed1983

Cigarette smoking and renovascular hypertension.

A retrospective cohort study to investigate the association between smoking and renal artery stenosis compared 71 patients with documented renovascular hypertension and 308 age-matched control patients with essential hypertension. 94% (30/32) of men and 74% (29/39) of women with renal artery stenosis had smoked cigarettes compared with only 43% (64/150) of men and 41% (65/158) of women in the control group. This striking relation was true for both patients with fibromuscular disease (71% smokers; 15/21) and patients with atherosclerotic lesions (88% smokers; 44/50). All renal artery stenosis groups had significantly higher systolic and diastolic blood pressures than the relevant control group. When the groups were stratified according to blood pressure, there were significantly more smokers in the renal artery stenosis group at every level of blood pressure.

Diastole↗
PubMed1983

Percutaneous transluminal renal angioplasty in renovascular hypertension due to atheroma or fibromuscular dysplasia.

We attempted percutaneous transluminal renal angioplasty in 89 patients with hypertension and renal-artery stenosis (including 51 with atheromatous and 31 with fibromuscular stenoses) who were then followed for an average of 16 months (range, 4 to 40). Angioplasty was technically successful in 87 per cent of the fibromuscular stenoses and in 57 per cent of the unilateral atheromatous stenoses but in only 10 per cent of the bilateral atheromatous stenoses. After successful angioplasty, blood pressure was reduced to normal or improved in 93 per cent of the patients with fibromuscular dysplasia and in 84 per cent of the patients with atheromatous disease. Angiographic follow-up at an average of 21.8 months in 15 patients showed persistent relief of the stenoses and a 12 per cent average increase in kidney size. Renal angioplasty is effective for long-term control of hypertension in patients with renal-artery stenosis due to fibromuscular dysplasia or unilateral non-ostial atheroma.

Adult↗
PubMed1983

Transhepatic portal venous embolization of varices: pros and cons.

Transhepatic portal venous embolization does not reduce immediate or long-term mortality or the incidence of rebleeding in patients with acute hemorrhage from gastroesophageal varices. Since in addition the procedure is not without risk to the operator, who is exposed to a considerable amount of radiation, the author recommends conservative treatment of acute variceal hemorrhage. Transhepatic portal venous embolization should be used only in patients in whom endoscopic sclerosis has failed and in whom there is reason to believe a selective splenorenal shunt can be successful.

Embolization, Therapeutic↗
PubMed1983

Arterial spasm during renal angioplasty.

Spasm of the renal arteries during transluminal angioplasty is a well-documented phenomenon with serious potential sequelae, particularly in young patients with fibromuscular dysplasia. The authors report their experience in 98 cases (105 arteries). Tolazoline, lidocaine, nitrates (or calcium blockers, if available), and heparin should be administered either directly into the renal artery or systemically prior to angioplasty to decrease the incidence and severity of spasm.

Adolescent↗
PubMed1982

Dose-related effects of manganese on the canine electrocardiogram.

We studied the dose-related effects of manganese, a slow channel blocker, on the ECG in seven anesthetized dogs. Incremental bolus doses of MnCl2, providing 0.1, 0.5, 1.0, 5.0, and 10.0 mg/kg Mn, were injected intravenously at sequential 10 minute intervals. Heart rate decreased from 175 +/- 5 beats/min (mean +/- SEM) to 137 +/- 6 after 5.0 mg/kg Mn (p less than .001). No significant decrease in rat occurred with lower doses. Mn at 10.0 mg/kg was lethal in six dogs following brief profound hypotension and bradycardia. The PR interval increased slightly after 0.5 mg/kg Mn, from 99 +/- 3 msec to 103 +/- 3 (p less than .01), to 106 +/- 4 msec (p less than .01) after 1.0 mg/kg, and to 117 +/- 4 msec (p less than .005) after 5.0 mg/kg. QRS width increased from 57 +/- 2 msec to 65 +/- 1 (p less than .005) after 1.0 mg/kg Mn and was not further prolonged after 5.0 mg/kg. The observed QT interval increased from 186 +/- 2 msec to 201 +/- 1 (p less than .025) after 1.0 mg/kg Mn and to 222 +/- 2 (p less than .01) after 5.0 mg/kg. The rate-corrected QT interval was also increased at these doses. These data suggest that important in vivo effects of manganese on atrioventricular and intraventricular conduction occur at doses which do not affect the heart rate.

Animals↗
PubMed1982

Incomplete myocardial reperfusion despite a patent coronary bypass: a generally unrecognized shortcoming of the surgical approach to coronary artery disease.

When assessing a coronary artery bypass graft, the patency rate is virtually the sole criterion of success. However, this fails to identify grafts which are patent by incompletely reperfuse the diseased vessel. Angiograms of 82 patients with 172 bypassed coronary arteries confirmed patency in 126 (73%); however, in 30 reperfusion was incomplete though the graft was patent, making the rate of complete reperfusion only 56% (96/172). Causes included localized narrowings in the region of the anastomosis [9], significant narrowing along the graft [6], pre-existing additional stenoses in the native vessel, remote from the anastomosis and the lesion [7], stenoses not present preoperatively but seen postoperatively in the native vessel, remote from the anastomosis and original lesion [6], and separate obstructions of unbypassed branches [2]. While incomplete reperfusion is often unavoidable and is certainly preferable to total occlusion, evaluation based purely on patency rates is misleading, since it overlooks the fact that a significant proportion of patent grafts will not totally reperfuse the diseased vessel.

Adult↗
PubMed1982

Comparison and significance of bypass patency rates in noncritical versus critical coronary obstruction.

Preoperative and postoperative angiograms were compared in 81 patients who had undergone coronary artery bypass surgery. In these patients, 135 bypassed vessels had had critical stenoses or total occlusion; 99 of these bypasses (73.3%) were patent. Of 36 bypassed vessels that had had noncritical stenoses, 26 (72.2%) were patent. This difference was not significant. Thus, competitive inflow does not lead to excessive graft failure in noncritically diseased vessels, and they can be bypassed with the same expectation of success as critically obstructed vessels. The risk and the advantages of bypassing mild lesions at the same time that severe obstructions are surgically treated are discussed.

Adult↗