Biomedical subjects

R J Rizzo

Publications and source records attributed to R J Rizzo.

At least 37 records · Page 2Linked to original sources

PubMed1995

The effect of pathophysiology on the surgical treatment of ischemic mitral regurgitation: operative and late risks of repair versus replacement.

Operative correction of ischemic mitral regurgitation (IMR) is associated with high risk approach. The objective of this retrospective study was to examine the interaction between the various underlying pathophysiologic mechanisms, the operative procedure, and their influence on short- and long-term outcomes. Over a 10-year period starting January 1984, mitral valve repair or replacement was performed on 150 patients with IMR. The age range was 42-86, mean 67, years; 71 (47%) were females; 139 (93%) were in NYHA functional class III or IV; 23 (15%) were reoperations; and 30 (20%) were in atrial fibrillation. Functional IMR due to annular dilatation or restrictive leaflet motion was present in 106 (71%), and structural IMR due to ruptured chordae or papillary muscle in 44 (29%). Mitral valve repair was performed in 94 (63%) with an annuloplasty ring employed in 80 (85%) patients. Mitral valve replacement was performed in 56 (37%), with 40 (71%) receiving a bioprosthesis (32 Hancock and 8 Carpentier-Edwards valves) and 16 (29%) a St. Jude valve. Coronary artery bypass graft surgery was performed in 139 (93%) patients. The overall operative mortality (OM) was 14/150 (9.3%). The OM for repair was 9.5% compared to 8.9% for replacement (P = NS). There was higher OM in the elderly, particularly in the repair group (P = 0.053), and a trend towards reduced OM in the recent years of the study (P = NS). No predictors of OM were identified by multivariate logistic regression analysis. Long-term follow-up was 98% complete and ranged from 2-120, mean 31.2, months for a total of 935 patient-years. The overall 5-year survival rate was 71 +/- 6%, with 91 +/- 5% for the replacement group compared to 56% +/- 10% for the repair group (P = 0.01). The functional subset of IMR who had a repair had the worse long-term survival (43 +/- 13%) compared to the structural/repair (76 +/- 13%) and structural/replacement groups (89 +/- 8%), and 92 +/- 7% for the functional/replacement group ((P = 0.0049). Multivariate logistic regression analysis identified the functional/repair group (hazards ratio 4.4; +/- 95%, confidence interval 1.6, 11, (P = 0.0031); and earlier years of surgery (hazards ratio 4.7; +/- 95% confidence interval 1.021; (P = 0.046) to be predictors of worse long-term survival. These results suggest that, in IMR, the underlying responsible pathophysiologic mechanisms appear to be the major determinants of survival, rather than the choice of the operative procedure.

Adult↗

PubMed1995

Repair of mitral regurgitation from myxomatous degeneration in the patient with a severely calcified posterior annulus.

Severe posterior annular calcification poses a particular challenge to mitral valve repair. In a series of 252 mitral valve repairs for myxomatous degeneration performed between 1980 and 1993, 14 patients had a severely calcified posterior mitral valve annulus. Ages ranged from 61 to 81 years. Twelve patients were preoperative NYHA Class III or IV, and five patients required concurrent coronary artery bypass procedures. Operative techniques included complete resection of the calcified posterior annulus, resections of portions of the posterior leaflet with leaflet advancement, and placement of an annuloplasty ring. There were no operative deaths and all patients had a postoperative echocardiographic confirmation of relief from mitral regurgitation. During a mean follow-up time of 36 months (6 months to 8 years), there has been one late valve reoperation and only one late death, from thromboembolism in a patient with atrial fibrillation. These data indicate that even in the presence of severe calcification of the posterior mitral annulus, mitral valve repair for myxomatous degeneration can be performed with a low-operative risk and satisfactory long-term results.

Aged↗

PubMed1995

Congenital abnormalities of the pancreas and biliary tree in adults.

Congenital abnormalities of the pancreaticobiliary tree may go undetected until adulthood. In adult patients with persistent and unexplained signs and symptoms, such as cholangitis, pancreatitis, jaundice, recurrent abdominal pain, and nausea and vomiting, a congenital anomaly of the pancreatic or bile duct must be considered and a low threshold for performing cholangiopancreatography is recommended. The most common congenital pancreaticobiliary abnormalities seen in adults are choledochal cyst, anomalous junction of the pancreatic and common bile ducts, aberrant biliary ducts, and pancreas divisum, with the following entities being more rarely seen: choledochoceles, multiple communicating intra- and extrahepatic duct cysts, Caroli disease, pancreaticobiliary abnormalities associated with situs anomalies, annular pancreas, and aberrant pancreatic ducts associated with enteric duplication cysts. Cholangiopancreatography allows confirmation of diagnosis and may demonstrate associated abnormalities such as choledocholithiasis or tumor. Recognition of congenital anomalies may aid in surgical planning and prevent inadvertent ductal injury. Although congenital pancreaticobiliary abnormalities are relatively uncommon, the increased prevalence of cholangitis, gallstones, and cholangiocarcinoma seen with the various types of biliary cystic disease and junctional anomalies and the increased association of pancreatitis seen with pancreatic anomalies make recognition of variant anatomy clinically important.

Adult↗

PubMed1995

A modified collection and rapid infusion system for shed whole blood autotransfusion during aortic aneurysm surgery.

We describe our experience in 10 patients (5 males) undergoing resection of a descending thoracic aortic aneurysm or a thoracoabdominal aortic aneurysm in which a modified shed whole blood collection and autotransfusion system was used. This modification allows several options for the processing and autotransfusion of shed blood: use of the cell saving device or the ultrafiltration of collected blood, and the autotransfusion of unprocessed shed whole blood. Either low dose heparin or sodium citrate was used for anticoagulation. All 10 patients underwent autotransfusion and volume resuscitation with the modified rapid infusion device. Total autotransfusion ranged from 1400 ml to 7843 ml. Ultrafiltration volumes ranged from 600 ml to 1100 ml. There were no intraoperative deaths and no patient reoperations for bleeding. Arterial blood gases, potassium, and platelet counts were all within the normal laboratory ranges. This modification enables the clinician to process poor quality shed blood and reinfuse whole blood, in an attempt to decrease the need for homologous blood products.

Aged↗

PubMed1994

Single-clamp technique: an important adjunct to myocardial and cerebral protection in coronary operations.

To determine the myocardial and cerebral protective properties of the single cross-clamp (group I; n = 160) versus the partial occluding clamp (group II; n = 150) technique for construction of the proximal anastomoses, a retrospective analysis of 310 patients operated on by the same surgeon was performed. Group I patients were older (median age, 70 versus 64 years; p < or = 0.0001), with 83 (52%), versus 41 (27%) in group II, 70 years and older (p < or = 0.0001). More group I patients were in New York Heart Association functional class IV (42 [26%] versus 22 [15%]; p = 0.008); more required preoperative balloon counterpulsation (35 [22%] versus 16 [11%]; p = 0.006); and more required emergent operation (20 [13%] versus 3 [2%]; p < or = 0.0001). Antegrade crystalloid cardioplegia was used in both groups. The median cross-clamp time was 58 minutes for group I versus 44 minutes for group II (p < or = 0.0001). However, there was no significant difference between the two groups in terms of the number of bypass grafts, the use of the mammary artery, or the bypass time. The operative mortality was 2.5% (n = 4) for group I versus 5.3% (n = 8) for group II (p = 0.16), and the perioperative myocardial infarction/low cardiac output state was seen in 6 patients (3.8%) in group I versus 18 patients (12%) in group II (p = 0.006). The median creatine kinase MB release was 13 U/L for group I versus 19 U/L for group II (p = 0.0029).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1994

Aortic valve endocarditis. Determinants of early survival and late morbidity.

BACKGROUND: Aortic valve surgery for endocarditis remains a high-risk procedure. The objective of this study was to analyze the interaction between the various subsets of endocarditis (native, prosthetic, healed, and active), timing of surgery, and their influence on early and late outcomes. METHODS AND RESULTS: During a 20-year period starting January 1972, 200 patients underwent aortic valve replacement for infective endocarditis (age range, 13 to 88 years; median, 53 years). There were 51 (26%) females, and 109 (55%) were in New York Heart Association functional class IV before surgery. Native valve endocarditis (NVE) and prosthetic valve endocarditis (PVE) were present in 132 (66%) and 68 (34%) patients, respectively. Surgery was required in 120 (60%) during the active phase (AE) and 80 (40%) during the healed phase (HE) of endocarditis. The main indication for surgery in the healed group was progressive congestive heart failure. The indications for the active group were congestive heart failure (68%), continuing active sepsis (70%), echocardiographic vegetation (28%), peripheral emboli (30%), and arrhythmias (13%). Streptococcal infections predominated in NVE, staphylococcal in PVE and AE; culture-negative endocarditis predominated in the healed group. Isolated aortic valve surgery was performed in 68% of the patients, and concomitant procedures (32%) included mitral valve and coronary bypass procedures. The overall operative mortality (OM) was 12.5%. The OM was 7.5% and 22% for NVE and PVE, respectively (P = .004), and 7% for HE versus 15% for AE (P = .06). The OM for early PVE was 33% versus 18% for late PVE (P < .05). Multivariate logistic regression analysis identified PVE and New York Heart Association functional class IV to be independent predictors for early death. Recurrent endocarditis occurred 26 times in 24 patients (11 early, 13 late), with three operative deaths in the early group, all due to residual staphylococcal infections. Freedom from recurrent endocarditis was significantly different between HE (96 +/- 3% and 86 +/- 6% at 5 and 10 years, respectively) and AE (89 +/- 3% and 83 +/- 4%, respectively (P = .02). Long-term survival for discharged patients was 81 +/- 3% and 63 +/- 5% at 5 and 10 years, respectively, with no significant difference between NVE, PVE, AE, and HE. CONCLUSIONS: These data suggest that for active endocarditis, surgery should be delayed to achieve a healed status provided there is no pressing need for immediate surgery. Patients with staphylococcal endocarditis, particularly on a prosthesis, should be operated on sooner and should be covered with antibiotics for an extended period to prevent recurrent PVE. This study stresses the need for aggressive antibiotic prophylaxis, particularly in the presence of a prosthesis.

Aortic Valve↗

PubMed1994

Rapid noninvasive diagnosis and surgical repair of acute ascending aortic dissection. Improved survival with less angiography.

Angiography has been considered the gold standard for the diagnosis of acute dissection of the ascending aorta, but it may increase mortality by imposing an unnecessary delay before surgical repair. In addition, coronary angiography has often been considered essential as well. From 1988 to 1993, 37 patients (median age 61 years, 30 men and 7 women) had acute dissection of the ascending aorta. All of the initial 15 patients (group I) had angiography, even through the diagnosis of aortic dissection had already been made noninvasively in 14; six (40%) of 15 died, three of aortic rupture and none of complications of coronary artery disease. Among the next 22 patients (group II), 21 had a noninvasive diagnosis of acute dissection of the ascending aorta (eight by echocardiography; 13 by computed tomography), and 19 (86%) were operated on without angiography; two died (9%, p = 0.03 versus group I) and neither death was due to aortic rupture or coronary artery disease. Overall, either root or selective coronary angiography was attempted in 18 of 37 patients, but it documented coronary artery disease in only two patients (11%). Coronary artery disease was found in four other patents at autopsy; three of them, including two that died of aortic rupture, had angiography that failed to reveal the coronary artery disease. Noninvasive diagnosis of acute dissection of the ascending aorta is reliable and avoids the risks and delays inherent in invasive angiography. Rapid noninvasive diagnosis of aortic dissection and avoidance of routine angiography appear to improve survival by expediting surgical intervention and thus decreasing the risk of aortic rupture.

Acute Disease↗

PubMed1994

Prevention of complement-induced pulmonary hypertension and improvement of right ventricular function by selective thromboxane receptor antagonism.

The effect of complement activation on the pulmonary vascular system and on right ventricular function was studied in sheep (n = 12) by injection of cobra venom factor. Animals were instrumented for measurement of pulmonary flow, mean pulmonary artery pressure, right ventricular stroke work, arterial blood gases, and systemic vascular resistance. Blood was sampled from the left atrium and pulmonary artery to measure thromboxane B2, the metabolite of thromboxane A2, by radioimmunoassay. After baseline measurements, animals were randomly assigned to receive a selective thromboxane receptor antagonist SQ30741 as a 10 mg/kg bolus with an infusion of 10 mg/kg per hour or else to receive vehicle. Cobra venom factor was then injected (30 U/kg) in all animals, and data were recorded at 15, 30, 60, 90, and 120 minutes. In control animals there was a 2.4-fold increase in mean pulmonary artery pressure and a 76% increase in right ventricular stroke work at 15 minutes from baseline (p < 0.05); these values remained elevated for 30 minutes and returned to baseline by 1 hour with no change in systemic vascular resistance. Arterial oxygenation decreased by 124% at 15 minutes and remained depressed through the experiment, but in treated animals oxygen tension remained unchanged from baseline. Thromboxane B2 increased 95% from baseline in the control group and 1.5 fold in treated animals and followed a similar time course as the functional measurements (p < 0.05). A pulmonary vascular thromboxane B2 gradient of approximately 1000 pg/ml was measured at 15 and 30 minutes in both control and treated groups. (p < 0.05) We conclude that after complement activation in this model pulmonary hypertension and decreased oxygen tension are mediated by thromboxane release from the pulmonary vascular bed. This increased afterload causes a stress on the right ventricle as demonstrated by the increased right ventricular stroke work. Selective thromboxane receptor antagonism may be a beneficial therapy for pulmonary hypertension in patients after cardiopulmonary bypass.

Animals↗

PubMed1994

The long-term results of mitral valve reconstruction for the "floppy" valve.

The myxomatous degenerated, prolapsed, or floppy mitral valve is the most common etiology of mitral regurgitation in North American populations. We performed mitral valve reconstruction for this diagnosis in 252 patients from 1984 to 1993. There were 165 males and 87 females ranging in age from 23 to 84 years (mean 64 years); 93 (37%) were > or = 70 years. One hundred eighty-six were New York Heart Association Functional Class III or IV and 29% (72) underwent concomitant coronary bypass operation. Operations included posterior leaflet resection, anterior leaflet resection treatment of chordal pathology by shortening or Gore-Tex replacement, and ring annuloplasty. There were five operative deaths for an operative mortality of 2%. The operative risk in patients under 70 years was 1 of 159 (0.6%) and 4 of 93 (4%) in patients older than 70 years. Ninety percent of patients are asymptomatic in a follow-up period extending 10 years, while structural valve degeneration requiring reoperation at 5 years was 85%. From 1990 to 1993 there has been a less than 5% absolute incidence of structural valve degeneration. Mitral valve reconstruction for complicated floppy mitral valve is feasible and offers excellent early and medium-term results.

Adult↗

PubMed1994

Long-term results of mitral valve reconstruction for regurgitation of the myxomatous mitral valve.

The myxomatous, degenerated, prolapsed or "floppy" mitral valve is the most common cause of mitral regurgitation in North America. Mitral valve reconstruction for mitral regurgitation was carried out in 219 consecutive patients with a myxomatous mitral valve from 1984 to 1993. Of the 139 men and 80 women, 23 to 84 years of age (mean 63 years), 36% of patients were 70 years of age or older, 77% were in New York Heart Association functional class III or IV, and 29% had coronary artery disease necessitating coronary bypass. The most common operation was posterior leaflet resection (161 patients [73%]). The anterior leaflet was resected in 14 patients, and both the anterior and posterior leaflets were resected in 15 patients. A variety of other techniques were used, including commissuroplasty and use of annuloplasty rings. A flexible Duran ring was used in 111 patients (51%), a Carpentier-Edwards ring in 44 patients (20%), and no ring was used in 64 patients (29%). Five operative deaths occurred (2.3%); four of the five deaths occurred in patients 70 years of age or older (5.1%); and one in 141 patients (0.7%) was younger than 70 years of age. In the late postoperative period (mean follow-up 2 years), 90% of patients had no symptoms, two had endocarditis, and seven patients had thromboemboli (transient in four, permanent in three). Structural valve degeneration requiring reoperation occurred late in 12 patients; eight were in posterior leaflet resection and two in anterior or anterior and posterior; six of 12 had no annuloplasty ring. The incidence of structural valve degeneration was less than 5% from 1990 to 1993. No systolic anterior motion of the mitral valve was seen with postoperative echocardiography before discharge. Actuarial analysis at 5 years for overall survival was 86% +/- 5%, freedom from infectious valve degeneration 97% +/- 2%, and freedom from thromboembolism 94% +/- 3%. Freedom from structural valve degeneration overall was 83% +/- 4%, with a flexible ring it was 89% +/- 6%, with a rigid ring it was 88% +/- 6%, and with no ring it was 67% +/- 12% (p = 0.03). Mitral valve reconstruction for complicated myxomatous disease of the mitral valve, regardless of leaflet involvement, is feasible and offers excellent early and late results.

Actuarial Analysis↗

PubMed1993

Decrease in operative risk of reoperative valve surgery.

We analyzed the risk of valve re-replacement in 640 patients reoperated on between 1980 and 1992. This represented 17% of total valve operations (640/3,764) during that period. A univariate and logistic multivariate analysis was carried out for four sequential periods for the 640 re-replacement patients to determine if changing methods of perfusion and myocardial protection affected recent results. There were 323 female and 317 male patients with a mean age of 58 years (range, 17 to 84 years). Ninety-seven (15%) had coronary artery bypass grafting, 135 (21%) were 70 years old or older, 377 (59%) were in New York Heart Association functional class III or less, and 263 (41%) were in functional class IV. The aortic valve was re-replaced in 245, the mitral valve in 289, and both aortic and mitral synchronously in 106. Four periods were analyzed: 1980 through 1982, 1983 through 1985, 1986 through 1988, and 1989 through 1992. The overall operative mortality was 65 of 640 patients (10%), falling from 12/73 (16%) in 1980 through 1982 to 23/268 (8%) in 1989 through 1992 (p = 0.05). Univariate and multivariate logistic analysis documented that New York Heart Association functional class was highly significant for operative mortality; operative mortality was 4% for functional classes I through III, and 19% for functional class IV (p < or = 0.001). The requirement for coronary bypass was of borderline significance (p = 0.05), and year of operation was also significant. Mortality for re-replacement of aortic valve fell from 15% to 10%, double valve from 20% to 9%, and mitral valve from 16% to 6%.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1993

Femoral veno-arterial extracorporeal life support with minimal or no heparin.

Recent technological advances in cardiopulmonary bypass circuits achieving surface bonding with heparin have permitted prolonged extracorporeal life support (ECLS) in experimental studies without the use of systemic anticoagulation. Excessive bleeding and the need for massive transfusions after extended ECLS with systemic heparinization have often led to the development of sepsis and multisystem organ failure. The Carmeda bioactive surface circuit, along with a Bio-Medicus centrifugal pump (Bio-Pump) and the femoral veno-arterial route, were used successfully in 3 patients requiring ECLS between April 1992 and December 1992. In 2 patients the need for ECLS was acute allograft dysfunction after orthotopic cardiac transplantation with no evidence of cellular rejection. Both patients were receiving multiple inotropes and intraaortic balloon counter-pulsation; their condition continued to deteriorate rapidly before the initiation of ECLS. The third patient failed to be weaned from cardiopulmonary bypass after myocardial revascularization for ischemic cardiomyopathy. Time on ECLS ranged from 57 to 128 hours. No systemic anticoagulation was used. One patient received no heparin, and the other 2 patients received intermittent heparin infusion to maintain an average activated clotting time of 195 and 214 seconds. Multisystem organ dysfunction present before initiation of ECLS was rapidly reversed, and all patients were weaned successfully without any immediate major complications. The ability to conduct prolonged ECLS without systemic anticoagulation and without repeat sternotomy opens new avenues for the use of this procedure in profound heart failure.

Blood Coagulation↗

PubMed1993

Aortic valve replacement in the elderly. Effect of gender and coronary artery disease on operative mortality.

BACKGROUND: Aortic valve replacement remains the treatment of choice for aortic valve disease, even in the extreme elderly who may present with advanced symptoms. Defining risk factors for short-term survival was the object of this study. METHODS AND RESULTS: This was a retrospective analysis of 717 patients at least 70 years of age who underwent aortic valve replacement alone or with coronary artery bypass graft between 1980 and 1992. Age range was 70 to 95 years, and mean age was 77 years; there were 529 septuagenarians (74%); 188 were octogenarians (26%); 326 were women (45%); and 386 patients (54%) had aortic valve replacement and coronary artery bypass graft. Atrial fibrillation/flutter or heart block was present in 16%, and 34% of patients were in New York Heart Association (NYHA) functional class IV. Aortic stenosis was present in 88%, and mechanical prostheses were used in 22% of patients. There were 47 deaths, giving an overall operative mortality of 6.6%, with 4.2% for aortic valve replacement and 8.8% for aortic valve replacement and coronary artery bypass graft (P = .01). The operative mortality for aortic valve replacement was 2.9% versus 10.3% for aortic valve replacement and coronary artery bypass graft in women (P = .006). The corresponding values for men were 5.6% and 7.4% (P = .31). Multivariate logistic regression showed coronary artery bypass graft and NYHA class IV to be significant predictors of operative mortality in women. The significant predictors in men were NYHA class IV, atrial fibrillation/flutter or heart block rhythm, and the use of mechanical prosthesis. Age was not a predictor of operative mortality in either sex. CONCLUSIONS: Aortic valve replacement carries an acceptable mortality rate in elderly patients. Female gender was a significant predictor of operative mortality in the concomitant coronary artery bypass graft group; however, gender was not a predictor of operative mortality in the isolated aortic valve replacement group. Advance stage of the disease process represented by NYHA class IV was a significant predictor of mortality for the whole group, stressing the need for earlier referral for surgery.

Aged↗

PubMed1992

Combined carotid and coronary revascularization: the preferred approach to the severe vasculopath.

The timing of carotid endarterectomy (CEA) and coronary revascularization (CABG) for concomitant disease is controversial. Results of combined CEA/CABG in 127 patients (age range, 46 to 82 years; mean age, 65 years; 61% male) from 1978 to 1991 were reviewed. Ninety-five patients (75%) were in New York Heart Association functional class III or IV, 48 (38%) had left main coronary artery disease, and 32 (28%) had depressed ejection fraction ( < 0.50). Forty (32%) had asymptomatic bruits, 61 (48%) transient ischemic attacks, and 26 (20%) prior strokes. Seventy-five (59%) had bilateral carotid stenosis, including 20 (16%) with contralateral occlusions. Perioperative mortality was 7 of 127 (5.5%), and all deaths were cardiac related. Myocardial infarctions occurred in 6 of 127 patients (4.7%) and were nonfatal in 3 (2.3%). Permanent strokes occurred in 7 of 127 (5.5%) and were ipsilateral in 5 (3.9%). Perioperative stroke did not occur in the asymptomatic group, but the risk was higher in those with prior stroke (19%) or with contralateral carotid occlusion (15%). The stroke risk for our patients with carotid disease having CABG without CEA is not known, but the literature reports rates as high as 14%. For our patients without known concomitant disease, the risk of permanent stroke was 1.0% (31/3012) for isolated CABG and 1.5% (7/482) for isolated CEA. The late results after CEA/CABG revealed a 5-year survival of 70% +/- 5%, which correlated with ejection fraction ( > or = 0.50, 81% +/- 5%; < 0.50, 45% +/- 11%; p < 0.003). Freedom from late permanent ipsilateral stroke was 97% +/- 2% at 8 years. Freedom from stroke at 5 years was lower among patients with a previous stroke (71% +/- 10%) compared with transiently symptomatic (90% +/- 4%) and asymptomatic (96% +/- 4%) patients (p < 0.03). Combined CEA/CABG is a useful option in this high-risk group of patients with extensive atherosclerosis; avoids a subsequent hospitalization, anesthetic, and delay period; and provides long-term protection from ipsilateral stroke.

Actuarial Analysis↗

PubMed1990

A comparative study of intraoperative angioscopy and completion arteriography following femorodistal bypass.

A prospective comparison of the findings on standard completion arteriography with those seen using videoangioscopy was done following 49 cases of "femorodistal" bypass grafting in 47 patients. The two techniques were compared with respect to the detection of technical defects, modification of the surgical procedures, early graft patency (72 hours), and complications. Completion arteriography was specific (95%) but only moderately sensitive (67%) compared with angioscopy for detection of technical problems. Following angioscopy, significant alterations in the surgical procedure were noted in 5 (10%) of the 49 cases. Early graft failure occurred in 3 (6.1%) cases but none were identifiably due to technical problems. Four patients suffered postoperative myocardial infarctions, 2 (4.2%) of which were fatal; no patients had contrast-induced allergies or renal failure. Angioscopy was measurably more accurate for the detection of technical problems than completion arteriography, but offered little information about distal arterial anatomy that may have an impact on graft patency or the use of antithrombotic therapy.

Aged↗

PubMed1990

Duplex scanning for assessment of mesenteric ischemia.

The accurate diagnosis of mesenteric arterial occlusive disease has in the past required invasive examination, primarily arteriography. Recent innovations in duplex ultrasound scan technology have for the first time provided a method for the noninvasive assessment of the splanchnic circulation in man. Mesenteric duplex scanning has been used successfully to measure postprandial changes in celiac and superior mesenteric arterial blood flow as well as changes in visceral flow produced by other pharmacologic stimuli.

Arteriovenous Shunt, Surgical↗

PubMed1990

Computed tomography for evaluation of arterial disease in the popliteal fossa.

The clinical details, arteriograms, and computerized tomographic (CT) scans of 28 patients with popliteal arteriopathies were reviewed retrospectively to determine the usefulness of CT for the diagnosis and treatment of these disorders. Arteriography diagnosed 70% and CT diagnosed 98% of the 45 popliteal disorders. Popliteal aneurysms were not detected by arteriography because of occlusion in seven (20%) patients and intraaneurysmal thrombus that produced no luminal compromise in two. Thrombus was identified by CT in 22 of 24 patient aneurysms and suspected as the source of digital embolization in 7. Graft aneurysms were identified by CT in two cases, but one was not detected by arteriography because of graft occlusion. Two mycotic aneurysms were identified, one by arteriography and not by CT because of misinterpretation of a periarterial hematoma. Popliteal entrapment was diagnosed by CT in three cases, and in two cases occlusion precluded diagnosis of entrapment by arteriography. Adventitial cystic disease was diagnosed accurately by CT in three cases, and in two there were no characteristic arteriographic abnormalities. In cases of entrapment and cystic disease, the CT findings allow the surgeon to plan his approach through a posterior incision, which in these two instances facilitates surgical technique. CT provides detail of the arterial wall, intraarterial contents, and surrounding musculoskeletal anatomy, all of which are useful for accurate evaluation of arterial disorders of the popliteal fossa.

Adult↗

PubMed1990

Mesenteric flow velocity variations as a function of angle of insonation.

This study was designed to quantitate variations in duplex ultrasound arterial flow velocities (cm/sec) in the common carotid artery and the superior mesenteric artery that were produced by changes in the angle of pulsed Doppler insonation. Duplex scanning was used to measure peak systolic flow velocity and mean velocity at angles from 30 degrees to 80 degrees; individual measurements were made at 10-degree increments in both the common carotid artery and the superior mesenteric artery in normal subjects. Peak systolic velocity in the common carotid artery varied from 86 cm/sec at 30 degrees to 168 m/sec at 80 degrees. Over the same transducer angle variation mean velocity ranged from 28 to 53 cm/sec. Similar changes in the superior mesenteric artery flow velocities were observed by varying the angle of insonation, where peak systolic velocity varied from 108 cm/sec (30 degrees) to 280 cm/sec (80 degrees), and mean velocity ranged from 29 cm/sec (30 degrees) to 71 cm/sec (80 degrees). Measurements taken from 70 to 80 degrees produced the most dramatic deviation from those taken at 60 degrees. In the common carotid artery the 70- and 80-degree angles produced 14% and 59% increases, respectively, in peak systolic velocity and 16% and 63% increases, respectively, in mean velocity. In the superior mesenteric artery 70-degree and 80-degree angles produced 16% and 120% increases, respectively, in peak systolic velocity and 17% and 111% increases, respectively, in mean velocity. At 80 degrees the percent increases in measured flow velocities for the superior mesenteric artery were significantly greater than those for the common carotid artery.(ABSTRACT TRUNCATED AT 250 WORDS)

Analysis of Variance↗