Usefulness of transcutaneous oximetry in vascular surgery

The assessment is presented of the value of transcutaneous oximetry in vascular surgery and in choosing the level of ischaemic limb amputation. Transcutaneous measurements of oxygen pressure (tcp02) were performed in 172 patients operated on for chronic ischaemia of the lower limbs before and three weeks after the operation. The studied subjects had the following operations done: bifurcated or unilateral aortofemoral bypass, femoropopliteal bypass, restoration of patency of the iliac and femoral arteries, lumbar sympathectomy, lower limb amputation. The studies were carried out using Hellige SM 361 oxymonitor and a similar Polish device. For oximetric measurements superficial skin sensor (Clark's polarographic electrode) was used, which was applied into the dorsum of the foot and medial crural surface. Transcutaneous oximetry seems to be a useful method for the assessment of the results of operations restoring blood flow in lower limb arteries. It makes possible to evaluate the results of lumbar sympathectomy. Transcutaneous measurements of oxygen pressure are also a useful method for the assessment of results of amputation of chronically ischaemic lower limb.     

Value of segmental limb blood pressures in predicting results of aortofemoral bypass

The efficacy of segmental limb blood pressure measurements, assessed noninvasively by Doppler ultrasound, in predicting the result of aortofemoral reconstruction was evaluated in fifty-two extremities with varying extent of aortoiliac and more distal arterial occlusive disease. Three prognostic correlates were analyzed: (1) preoperative proximal thigh/arm pressure index (TPI); (2) preoperative pressure gradient between adjacent leg segments (proximal thigh, above-knee, below-knee, and ankle), normally less than 30 mm Hg; and (3) early postoperative increase in the ankle/arm pressure index (API). After aortofemoral bypass, forty-one limbs (79 per cent) were asymptomatic or improved and eleven were unimproved. The mean TPI in extremities benefiting from aortofemoral bypass, 0.82 +/- 0.17 (+/-1SD) was significantly less than that of unimproved limbs, 1.01 +/- 0.09 (p less than 0.01). Aortofemoral bypass was beneficial in all twenty limbs with normal leg pressure gradients. Conversely, six of twenty-five legs with one abnormal gradient and five of seven with two abnormal gradients failed to improve. The postoperative increase in API was 0.1 or more in all forty-one improved extremities and was less than 0.1 in all eleven failures. Although eleven of thirty-two limbs (34 per cent) with arteriographic evidence of combined aortoiliac and subinguinal occlusive disease were not improved after proximal bypass, the result of operation could not be predicted from the angiographic pattern or severity of distal disease. Segmental limb blood pressures provide useful predictive indices of the efficacy of aortofemoral bypass and the potential need for more distal reconstruction in multisegmental disease.     

The propeptide of subtilisin BPN'' as a temporary inhibitor and effect of an amino acid replacement on its inhibitory activity

PURPOSE: To determine the potential benefits of applying laparoscopic techniques for the intraabdominal insertion of aortofemoral grafts and to compare results with those of conventional surgery. METHODS: Having previously demonstrated the feasibility of a totally laparoscopic aortofemoral bypass technique using carbon dioxide peritoneal insufflation in a porcine model, we now report our first human experience with this laparoscopic technique in a 49-year-old man. RESULTS: The patient's postoperative course was marked by his minimal requirements for analgesia, early ambulation, and discharge from the hospital in the morning of the third postoperative day. CONCLUSIONS: The benefits of a laparoscopic approach to aortobifemoral bypass grafting in terms of financial savings and earlier rehabilitation in this patient was significant. This less-invasive procedure warrants further investigation.     

Challenging the future: impact of information technology on dietetics practice, education, and research

PURPOSE: We retrospectively evaluated balloon angioplasty with intraluminal stenting to define applicability, early results, cost, and length of stay. METHODS: Seventy-three patients underwent 94 aorto-iliac angioplasties with intraluminal stents from October 1991 through July 1993. All had disabling claudication or rest ischemia. RESULTS: Mean follow-up was 10.2 months and was 90.4% complete. Ninety percent of procedures were immediately successful. There were no deaths within 30 days of surgery. Complications occurred in 13%. The ankle:brachial indices improved in all groups. Functional class improved in all groups. In class 4, limb salvage or a benefit on level of amputation was universal. Length of stay ranged 33% to 82% less than when aorto-iliac or aortofemoral bypass were undertaken (diagnosis-related group 39.25). Hospital charges for stent procedures ranged 25% to 66% less than for aorto-iliac or aortofemoral bypass (diagnosis-related group 39.25). CONCLUSION: The procedure is widely applicable, with an apparent initial advantage in mortality, morbidity, charges, and length of stay. Durability is unproven.     

When to ambulate the patient with a vascular graft in the groin

Ankle blood pressure studied pre- and postoperatively in 60 patients after aortofemoral and femoral distal bypass surgery showed no adverse effect after major positional changes (supine, sitting, and standing). Early ambulation was not harmful to graft dynamics in this group of patients.     

Effects of afferent and efferent celiac nerves on acute gastric lesions: due to changes in blood flow?

Since ablation of afferent nerves prior to stress results in increased severity of acute gastric mucosal lesions, afferent nerves are thought to mediate protective mechanisms in the stomach. These mechanisms are known to include vasodilation of gastric mucosal vessels; vasodilation is thought to allow the gastric mucosa to respond to injurious substances. However, it is not known whether other aspects of mucosal health, independent of those caused by increased blood blow, are affected by afferent blockade. This study compared gastric blood flow and acute gastric mucosal lesions during stress in rats with either chemical sympathectomy or afferent blockade. The purpose of the study was to compare the lesion index and blood flow in each treatment group. The lesion index was highest in rats with afferent blockade and lowest after sympathectomy. Gastric blood flow was partially preserved after sympathectomy, but was not greatly increased, suggesting that some of the effects observed after afferent blockade are unrelated to changes in blood flow.     

Current options in prosthetic vascular graft infection

Debate continues over which procedure is the best treatment for prosthetic graft infections. We retrospectively reviewed the medical records at our institution for all vascular graft infections that occurred from 1985 to 1995 to evaluate their occurrence, treatment, and outcome. Twenty-four patients had prosthetic graft infections. The average patient age was 62 years, and 67 per cent of the patients studied were men. The initial operation was for treatment of occlusive disease in 92 per cent of the patients, and aortofemoral bypasses were the most common procedures performed (15 of 24 patients, 63%). The average interval from graft implantation to presentation of infection was 29 months. In lower-extremity bypasses, the site of infection was most commonly in the groin (87%). Gram-positive organisms, including coagulase-negative Staphylococcus (32%) and Staphylococcus aureus (28%), were the most frequently isolated bacteria. Thirty procedures were performed for management of the graft infections. Extra-anatomic bypass was associated with no recurrent graft infections. Graft preservation was successful in two cases of early S. aureus infection (less than 1 year after original procedure), and in situ graft replacement was successful in all four cases of late-appearing coagulase-negative Staphylococcus infection (more than 1 year after original procedure). Both treatments failed in all five cases of Gram-negative infection (P = 0.008 by Fisher's exact test). The overall mortality and amputation rates were 17 per cent and 21 per cent, respectively, without significant differences between the treatment modalities. Extra-anatomic bypass remains the best treatment for prosthetic graft infection. In situ replacement and graft preservation treatments should be selective and based on presentation of the infection and the type of pathogenic organism.     

Aortic corset syndrome

The majority of proximal anastomotic complications of aortofemoral bypass grafts are related to the formation of pseudoaneurysms or true proximal aneurysmal dilation of the residual infrarenal aorta. The late development of occlusive disease at the proximal anastomosis is an extremely rare event. We report two patients in whom symptomatic stenoses developed involving the proximal anastomoses of aortofemoral bypass grafts originally placed for aortoiliac occlusive disease. Surgical exploration demonstrated the presence of a constricting prosthetic corset wrapped around the proximal suture line of each graft. Exuberant neointimal hyperplasia was responsible for both stenoses.     

Local complications after arterial bypass grafting

We have documented prospectively the problems occurring after 496 arterial bypass grafts (149 aortoiliac, 238 femorodistal, 65 extra-anatomic, and 44 others) implanted during the period 1987 to 1991 in a district general hospital. Postoperative bleeding occurred early in 14 (2.8%), and later (because of infection) in 3 (0.6%). Early graft occlusion (< 30 days) was seen in 2.9% aortofemoral, 10.4% femoropopliteal, and 25.3% femorotibial grafts, and amputation was required after 6.9% grafts. Wound problems were most common after femorotibial bypass--weeping of fluid in 3% and dehiscence or infection in 13.9%. Lymphatic collections occurred after 1.2% operations involving groin incisions. Graft sepsis was usually late, affecting 6% aortofemoral, 2.9% femorodistal, and 7.7% extra-anatomic grafts, but no intra-abdominal aortic grafts. These figures are probably representative of the complication rates seen by many surgeons and serve as an example for comparison and criticism.     

A randomised controlled trial of a low-molecular-weight heparin (Enoxaparin) to prevent deep-vein thrombosis in patients undergoing vascular surgery

The incidence of postoperative deep vein thrombosis (PDVT) after aortic surgery and lower limb revascularisation has not been assessed by a large prospective study. In a prospective randomised trial the effect of a low-molecular-weight heparin fragment, Enoxaparin (ENX) 4200 anti factor Xa IU once daily was compared to that of unfractionated heparin (UFH) 7500 IU twice daily. Two hundred and thirty-three consecutive patients were classified into three groups, aortic or aortoiliac and aneurysmectomy (n = 75), aorto-femoral bypass for atherosclerotic disease (n = 71), and femoropopliteal or femorodistal bypass (n = 87). Patients were analysed for development of deep vein thrombosis by Duplex scanning and, if positive, by venography between the seventh and tenth postoperative day. PDVT was present in 10 patients in the ENX group and in four patients in the UFH group (8.2 and 3.6% respectively, NS). The incidence of PDVT was 8% after aortic or aortoiliac aneurysmectomy, 7% after aortofemoral revascularisation, and 3.4% after femoropopliteal or femorodistal bypass. The overall incidence of PDVT after aortic surgery was 7.5% (95% CI 5.4-9.7). There was no pulmonary embolism. Intra-operative blood loss and postoperative bleeding events did not differ significantly between the ENX and UFH groups. After 1 month follow-up, no clinical event or death could be related to PDVT or pulmonary embolism. In conclusion, in vascular surgery ENX is as safe and effective in the prevention of PDVT as is UFH.     

Regional blood flow during pulsatile cardiopulmonary bypass and after circulatory arrest in an infant model

BACKGROUND: Pulsatile perfusion systems have been proposed as a means of improving end-organ perfusion during and after cardiopulmonary bypass. Few attempts have been made to study this issue in an infant model. METHODS: Neonatal piglets were subjected to nonpulsatile (n = 6) or pulsatile (n = 7) cardiopulmonary bypass and 60 minutes of circulatory arrest. Cerebral, renal, and myocardial blood flow measurements were obtained at baseline, on bypass before and after circulatory arrest, and after bypass. RESULTS: Cerebral blood flow did not differ between groups at any time and was diminished equally in both groups after circulatory arrest. Renal blood flow was diminished in both groups during bypass but was significantly better in the pulsatile group than in the nonpulsatile group prior to, but not after, circulatory arrest. Myocardial blood flow was maintained at or above baseline in the pulsatile group throughout the study, but in the nonpulsatile group, it was significantly lower than baseline during CPB prior to circulatory arrest and lower compared with baseline and with the pulsatile group 60 minutes after CPB. CONCLUSIONS: Pulsatile bypass does not improve recovery of cerebral blood flow after circulatory arrest, may improve renal perfusion during bypass but does not improve its recovery after ischemia, and may have beneficial effects on myocardial blood flow during bypass and after ischemia compared with nonpulsatile bypass in this infant model.     

Combined effect of nisin and high hydrostatic pressure on destruction of Listeria innocua and Escherichia coli in liquid whole egg

BACKGROUND: Thrombosis is the most frequent late complication of surgical procedures in the aortofemoral area. In the presence of aortobifemoral bypass, graft limb occlusion generally occurs within the first two years. Various techniques have been proposed to revascularize the ischemic limb. Personal experience in the treatment of occlusions of aorto-femoral bypasses branch by femoro-femoral bypasses is reported and the immediate and long-term results are analyzed. METHODS: The study was retrospective and the medium follow-up was 51 months (1-14 years). The patients were all operated from 1976 to 1995 in the Division of Vascular Surgery of the University of Bari. The group consisted of 40 patients affected by unilateral occlusion that occurred after aorto-femoral bypass. The femoro-femoral bypass was performed using non-ringed 6 or 8 mm Dacron prostheses; the proximal anastomosis was made a few cm above the femoral anastomosis of the permeable branch of the existing aorto-bifemoral bypass and the distal anastomosis on the cross-leg profunda femoris. Postoperative follow-up consisted of clinical examination, continuous wave Doppler examination or US-color-Doppler scan in order to assess the permeability of the graft. RESULTS: The immediate results showed 2 and long-term results 9 occlusions of the bypass. No perioperative mortality was observed. CONCLUSIONS: In conclusion the authors consider the use of femoro-femoral bypass indicated in a high number of patients affected by unilateral occlusion of the aorto-bifemoral bypass.     

Effects of surgical sympathectomy on skin blood flow in a rat model of chronic limb ischemia

The role of lumbar sympathectomy in the treatment of limb ischemia secondary to arteriosclerosis obliterans has been controversial. Increased temperature and rubor of the skin, which usually follow sympathectomy, have generally been interpreted as indicative of improved nutritive skin blood flow. However, the existence of a (nonnutritive) thermoregulatory level of skin microcirculation makes such an extrapolation questionable. We investigated the total (mainly thermoregulatory) skin blood flow (TSBF) in the hindlimb of 15 male Lewis rats by means of laser Doppler flowmetry and the nutritive skin blood flow (NSBF) by means of capillary microscopy (red blood cell velocity). Transcutaneous oximetry was used to assess skin oxygenation (SO). Measurements were performed before and 2 and 28 days after ligation of the common iliac and iliolumbar artery. Subsequently, either a surgical resection of the sympathetic chain (L2-L6) was performed or a sham operation. Measurements were repeated 2 and 28 days later. For the group of 15 rats as a whole, TSBF (p < 0.05), NSBF (p < 0.05), and SO (p < 0.05) were found to be drastically reduced at day 2 after litigation compared to preligation values. This reduction partially recovered during the following weeks. TSBF (p < 0.05) and NSBF (p < 0.05), however were still reduced at day 28 after ligation compared to preligation values, whereas the SO at this time tended to be lower (p = 0.11). In the sympathectomy group the TSBF was found to be increased at day 2 (p < 0.05) and day 28 (p < 0.05) after sympathectomy, both compared to values obtained at day 28 after ligation. Sympathectomy did not have an effect on NSFB and SO. The sham procedure had no effect on the TSBF, NSBF, or SO. These results indicate that in case of lower limb ischemia, sympathectomy improves skin blood flow at the thermoregulatory but not the nutritive level of skin microcirculation. This may be related to the fact that the thermoregulatory vessels are mainly sympathetically controlled, whereas the nutritive capillaries are mainly controlled by local (nonneural) factors.     

Effects of amphetamine and illumination on activity following frontal ablation

In 15 patients undergoing aortofemoral bypass, partial thromboplastin time (PTT) tests before and following intravenous administration of 75 U. per kilogram of heparin at zero, 30, 60, 90, and 120 minutes were determined for study of control of anticoagulant adequacy. The results demonstrate clearly that this amount provides excellent protection against thrombosis without bleeding complications. For intraoperative assay of heparin level effectiveness, the PTT test is advised. This test showed that a value of 250 percent of control still existed 75 minutes following the administration of heparin.     

Effects of various flow types on maternal hemodynamics during fetal bypass: is there nitric oxide release during pulsatile perfusion?

OBJECTIVE: This study investigates the role of various flow conditions on maternal hemodynamics during fetal cardiopulmonary bypass. METHODS: Normothermic fetal bypass was conducted under pulsatile, or steady flow, for a 60-minute period. Fetal lamb preparations were randomly assigned to 1 of the 3 groups: steady flow (n=7), pulsatile flow (n=7), or pulsatile blocked flow bypass (n=7), where fetuses were perfused with Nomega-nitro-L-arginine after the first 30 minutes of pulsatile flow to assess the potential role of endothelial autacoids. RESULTS: Maternal oximetry and pressures remained unchanged throughout the procedure. Under fetal pulsatile flow, maternal cardiac output increased after 20 minutes of bypass and remained significantly higher than under steady flow at minute 30 (8.8+/-0.7 L x min(-1) vs 5.9+/-0.5 L x min(-1), P=.02). Maternal cardiac output in the pulsatile group also remained higher than in both steady and pulsatile blocked flow groups, reaching respectively 8.7+/-0.9 L x min(-1) vs 5.8+/-0.4 L x min(-1) (P=.02) and 5.9+/-0.3 L min(-1) (P=.01) at minute 60. Maternal systemic vascular resistances were significantly lower under pulsatile than under steady flow after 30 minutes and until the end of bypass (respectively, 9.1+/-0.6 IU vs 12.7+/-1.1 IU, P=.02 and 8.9+/-0.5 IU vs 12.9+/-1.2 IU, P=.01). Infusion of Nomega-nitro-L-arginine was followed by an increase in systemic vascular resistances from 9.3+/-0.7 IU, similar to that of the pulsatile group, to 13.5+/-1 IU at 60 minutes, similar to that of the steady flow group. CONCLUSIONS: Maternal hemodynamic changes observed under fetal pulsatile flow are counteracted after infusion of Nomega-nitro-L-arginine, suggesting nitric oxide release from the fetoplacental unit under pulsatile fetal flow conditions.     

Surgical treatment for aneurysms of the descending aorta using temporary perfusion by a centrifugal pump: clinical analysis of 33 cases

Since 1987, 33 patients have undergone surgery at Kobe University Hospital for aneurysm of the descending aorta using left heart bypass with a heparin-coated centrifugal pump and heparin-coated tubes. Sixteen patients had true aneurysms of the descending thoracic aorta, 7 had thoracoabdominal aneurysms, and 10 had aortic dissection (DeBakey's Type III). Heat exchangers and oxygenators were not included in the bypass circuit in any of the cases. Perfusion time was from 42 to 205 min (average 90 min). Left heart bypass was established with 1 mg/kg of systemic heparinization in 5 cases, 0.5 mg/kg in 5 cases, and 0 mg/kg in 23 cases. There were no complications such as perioperative embolism, acidosis, or hypothermia. During aortic cross-clamping, the arterial pressure of the lower extremity was maintained above 70 mm Hg, but there was no relationship between the distal perfusion pressure and bypass flow. The urine output during left heart bypass was related to the distal perfusion flow by centrifugal pump. Of 23 patients who underwent bypass with less than 40 ml/kg/min of distal perfusion flow, 7 showed transient renal dysfunction postoperatively, and 1 developed postoperative renal failure. The other patients who were bypassed with over 40 ml/kg/min of pump flow stayed in the normal range of renal function. Postoperative paresis occurred in 2 patients, who were also perfused with less than 40 ml/kg/min of bypass flow. It could be concluded that left heart bypass by centrifugal pump is safe and acceptable as a circulatory support in the surgical treatment of aneurysm of the descending aorta.(ABSTRACT TRUNCATED AT 250 WORDS)     

Introduction of video endoscopic vascular surgery of the pelvic area

The fact that operative lethality and other typical postoperative complications following surgical treatment of aortoiliac atherosclerotic disease are mainly related to the surgical trauma (derived from the extensive abdominal incision and dissection), but not to the classical arterial reconstruction itself, has led us to develop a videoendoscopic aortoiliacal surgical method which is supposed to diminish the potential postoperative complications. Thus, a new endoscopic instrument set for vascular surgery has been developed in close cooperation with Aesculap AG Tuttlingen, Germany. After evaluating the basic techniques of videoendoscopic patching and end-to-side anastomosis with the newly designed instruments on a training model (n = 50), the feasibility of videoendoscopic vascular surgery on aortoiliacal vessels was tried out on human corpses (n = 8). The positive results of the initial survey have finally encouraged us to conduct our first series of animal studies on piglets (n = 25). The investigation regarding ultrasonically monitored blood flow in the femoral arteries after videoendoscopic aortofemoral bypass grafting and other systemic, hemodynamic parameters showed positive results. No complications were encountered in any of the standardized animal studies. Favorable activity levels were recorded. Meanwhile we have performed 5 extraperitoneal videoendoscopic aortofemoral artery bypasses in patients with aortoiliac occlusive diseases. One patient in whom we had occluded the inferior mesenteric artery died due to an ischaemic colitis. The other patients had an uneventful postoperative course. The videoendoscopic vascular procedures were carried out according to the rules of conventional vascular surgery. Nevertheless, further experimental research and development of endoscopic instruments have yet to be done, to optimize the new surgical method and to clarify the advantages of videoendoscopic vascular surgery.     

The role of profundaplasty in revascularization of the lower extremity

Profundaplasty has been performed on 112 limbs (88 primary and 24 secondary) in eighty-five men. Seventy-six limbs had incapacitating claudication, twenty-three rest pain, and thirteen either gangrene or ischemic ulceration. In thirty-six limbs treated by profundaplasty alone there were no deaths but five subsequently had amputation for ischemic pain. In the seventy-six limbs treated by profundaplasty plus other operative augmentation there were three operative deaths and one late death; three required further operative surgery and in four amputation was necessary. Oblique arteriographic films of the femoral area are essential for evaluation of the profunda femoris artery. Both radionuclide and Doppler pressure studies confirmed physical and arteriographic findings. The latter would appear superior because of ease of availability and cost. After profundaplasty alone and aortofemoral bypass there was a moderate increase in calf blood flow, but in only those with a patent superficial femoral artery did blood flow and pressure studies return to within normal limits. Profundaplasty is an important addition to the armamentarium of the vascular surgeon in dealing with arteriosclerotic insufficiency of the lower extremities.     

Endothelin receptor blockade prevents the rise in pulmonary vascular resistance after cardiopulmonary bypass in lambs with increased pulmonary blood flow

BACKGROUND: Children with increased pulmonary blood flow may experience morbidity as the result of increased pulmonary vascular resistance after operations in which cardiopulmonary bypass is used. Plasma levels of endothelin-1, a potent vasoactive substance implicated in pulmonary hypertension, are increased after cardiopulmonary bypass. OBJECTIVES: In a lamb model of increased pulmonary blood flow after in utero placement of an aortopulmonary shunt, we characterized the changes in pulmonary vascular resistance induced by hypothermic cardiopulmonary bypass and investigated the role of endothelin-1 and endothelin-A receptor activation in postbypass pulmonary hypertension. METHODS: In eleven 1-month-old lambs, the shunt was closed, and vascular pressures and blood flows were monitored. An infusion of a selective endothelin-A receptor blocker (PD 156707; 1.0 mg/kg/h) or drug vehicle (saline solution) was then begun 30 minutes before cardiopulmonary bypass and continued for 4 hours after bypass. The hemodynamic variables were monitored, and plasma endothelin-1 concentrations were determined before, during, and for 6 hours after cardiopulmonary bypass. RESULTS: After 90 minutes of hypothermic cardiopulmonary bypass, both pulmonary arterial pressure and pulmonary vascular resistance increased significantly in saline-treated lambs during the 6-hour study period (P <.05). In lambs pretreated with PD 156707, pulmonary arterial pressure and pulmonary vascular resistance decreased (P <. 05). After bypass, plasma endothelin-1 concentrations increased in all lambs; there was a positive correlation between postbypass pulmonary vascular resistance and plasma endothelin-1 concentrations (P <.05). CONCLUSIONS: This study suggests that endothelin-A receptor-induced pulmonary vasoconstriction mediates, in part, the rise in pulmonary vascular resistance after cardiopulmonary bypass. Endothelin-A receptor antagonists may decrease morbidity in children at risk for postbypass pulmonary hypertension. This potential therapy warrants further investigation.     

Morphometric analysis of CD4+, CD8+, and gamma/delta+ T-lymphocytes in lymph nodes of cattle vaccinated with Brucella abortus strains RB51 and 19

We have often experienced false positive results of the stress Thallium-201 myocardial scintigraphy (TL) for the evaluation of artery bypass graft patency after coronary artery bypass surgery (CABG). The purpose of this study is to clarify the frequency and the clinical significance of this findings. Sixty-two patients undergoing coronary angiography (CAG) after CABG were studied. These patients had undergone at total of 156 bypasses (artery grafts 108, saphenous vein grafts 48, mean bypass grafts number 2.65/cases), and the mean period from CABG to TL was 41.6 +/- 34 days. The territories of stress induced ischemia were divided into 3 territories; left anterior descending (LAD), right coronary artery (RCA), and left circumflex (LCX) territories. Patency of the bypass grafts was estimated on the absence of transient perfusion defect (TPD) on TL images. The incidence of false positive results was higher in Dipyridamole TL (38%) than in Exercise TL (18%) and higher in LAD territories (38%) than in RCA (11%) and LCX (13%) territories. All false positive cases showed no evidence of chest pain and significant ST-T change during stress TL test. High incidence of false positive results of stress TL test was observed for the evaluation of artery bypass graft patency after CABG.