Assessment of cardiovascular risk in waiting-listed renal transplant patients: a single center experience in 558 cases.

Cardiac screening is recommended to prevent cardiovascular death after renal transplantation. This retrospective observational study illustrates the results of application of a cardiac assessment algorithm in a series of 558 renal transplant candidates at a single center in Turin, Italy. A dipyridamole-stress sestamibi myocardial scintiscan (DMS) performed in 302/558 (54.1%) cases was positive in 52 (17.2%), negative in 200 (66.2%), borderline in 16 (5.3%), and with signs of previous necrosis in 34 (11.4%). Coronary lesions detected by angiography in 48.1% of the 52 positives were treated medically (13.5%) or by percutaneous/surgical procedure (34.6%). Coronary lesions were detected in 14.1% of asymptomatic population subgroup. The minor and major cardiovascular event rates and the cardiovascular death rate were 1.9%, 0%, and 0%, respectively, in positive DMS group (high-cardiological risk) vs. 10%, 4.5%, and 3.5% in the negatives (p > 0.5; n.s.). It is suggested that not increased cardiovascular event or deaths rates in the high-risk group reflect early coronary lesion detection and correction. Since 55.9% of cardiovascular events or deaths occurred in the negative group more than 24 months after the DMS, its mandatory repetition every two yr after a negative finding is recommended.

Imaging data suggesting acute pyelonephritis in the kidney graft: report of five cases with atypical clinical presentation.

Acute pyelonephritis is a common complication of kidney transplantation, occurring in up to 1% of grafts. Diagnosis is mainly clinical and atypical presentations have seldom been reported. The diagnostic role of imaging techniques has not been defined. Five cases of acute graft pyelonephritis are reported (three kidney, two pancreas-kidney grafts). The patients (median age 48 years) comprised three females and two males. Median post-transplant follow-up was 3 months, with three patients having predisposing factors for diabetes and one for an enteric bladder. None of the patients presented the 'classic' diagnostic tetrad (i.e. fever, positive urine cultures, low urinary tract symptoms and serum creatinine increase); although, at diagnosis, two of five patients presented with fever, one had increased creatinine levels and one had positive urine cultures. Of note, three patients had leucocyte casts at urinary sediment analysis, thus raising clinical suspicion. Renal ultrasounds were negative in all patients. Renal (99m)Tc-MAG3 (mercaptoacetyltriglycine) scintigraphy, which was used for the definition of kidney function impairment (one patient) or because of the presence of urinary casts (three patients), or after the biopsy diagnosis to locate the parenchymal lesions (one patient), was positive in all patients. The presence and pyelonephritic origin of the parenchymal lesions was confirmed by nuclear magnetic resonance or computed tomography scans. Acute graft pyelonephritis may develop in the absence of a full-blown clinical picture. Smouldering symptoms may occur in the presence of large perfusion deficits. (99m)Tc-MAG3 scintigraphy could be an important diagnostic tool in such cases.

Circulating Fc-receptor blocking factors in IgA nephropathies.

Twenty-one patients with primary IgA nephropathy, 7 patients with Henoch-Schönlein nephritis and 4 patients with IgA nephropathy associated to alcoholic liver cirrhosis were tested for Fc-receptor phagocyte function by measuring the clearance of radiolabelled IgG-sensitized erythrocytes in vivo and the immune phagocytosis by monocytes in vitro. Meanwhile IgG-, IgA-, IgA1-, IgA2-, containing immune complexes, the complement components C3, C4, C3d and the HLA-A, B, DR phenotype were determined. The patients with major urinary abnormalities were well discriminated from those with only minimal hematuria by a defective macrophage function (p less than 0.01) and high levels of IgA immune complexes (p less than 0.02). Since non HLA-A, B, C, DR phenotype was prevalent in patients who had defective Fc-receptor function, whereas a significant correlation was found between Fc-receptor impairment and levels of IgA immune complexes, it appears likely that circulating blocking factors, possibly related to IgA containing immune materials, may impair macrophage function in IgA nephropathies.

Complete reversal of the nephrotic syndrome after preemptive pancreas-kidney transplantation: a case report.

BACKGROUND: Nephrotic syndrome due to diabetic nephropathy is presently considered an indication for pancreas-kidney transplantation even in the absence of severe renal failure. Reversal of the nephrotic syndrome has been reported, but the mechanisms of this effect are unclear. AIM: To describe the renal morphofunctional pattern and the pattern of proteinuria before and after preemptive pancreas-kidney transplantation. METHODS: Methods included quantitative and qualitative assessment of proteinuria as well as renal ultrasound and scintiscan. CASE REPORT: A 42-year-old woman with type 1 diabetes since age 24 had widespread end-organ damage. Renal biopsy (2001) showed a mainly nodular pattern of diabetic nephropathy. Following referral (1999), her serum creatinine ranged from 1.6 to 2.2 mg/dL, with nephrotic range proteinuria (glomerular nonselective, tubular complete). Renal scintiscan revealed bilateral, symmetric, well-perfused kidneys. The functional data before pancreas-kidney graft (February 2003) were: serum creatinine 1.6 mg/dL, creatinine clearance 58 mL/min, serum albumin 2.6 g/dL, proteinuria 9.1 g/d. At hospital discharge (March 2003), the creatinine was 1.2 mg/dL, the creatinine clearance 97 mL/min, the proteinuria 0.676 g/d. Two months later, the creatinine was 1.2 mg/dL and proteinuria 0.421 g/d. A renal scintiscan demonstrated the functional prevalence of the grafted kidney (77% of total function), with vital, almost completely excluded native kidneys (functional contribution, 11.5% each). Proteinuria, ranging from 0.3 to 0.6 g/d, showed a physiological pattern. CONCLUSIONS: Functional exclusion of the native kidneys by renal scintiscan gives morphological support to reversal of the nephrotic syndrome.

[99mTc-DTPA scintigraphy in renal transplantation. Limitations related to the immunosuppressor used]. / La scintigrafia con 99mTc-DTPA nel trapianto renale. Limiti correlati all'immunodepressore usato.

The diagnostic tools used to achieve an assessment of allograft dysfunction should be as noninvasive as possible, because kidney graft recipients are fragile patients and quite often the need is for repeated investigations. In order to evaluate the reliability and accuracy of such a method, in this case scintigraphy with 99mTc-DTPA, the authors retrospectively studied 2 groups of kidney transplanted patients, having two different basic immunosuppressive regimens: group A--86 patients--taking steroids and azathioprine; group B--93 patients--taking steroids and cyclosporine. A total of 722 scans were retrospectively compared with scintigraphic information: 196 episodes of allograft dysfunction were due to acute rejection: 118 in group A, 78 in group B; 117 episodes were due to ATN: 75 in group A, 42 in group B; 11 episodes were ascribed to CyA acute nephrotoxicity. Group A and B behave differently in respect of the perfusion index. Only in group A were perfusion indexes statistically different in rejection, ATN and nephrotoxicity. Anyway, it must be stressed that, even if in group B, scintigraphy cannot be considered an accurate diagnostic method, it is somehow a helpful tool because it gives information about a worse perfusion of the graft, independently of the underlying pathology.

[Acute propafenone poisoning. Description of a case]. / Intossicazione acuta da propafenone. Descrizione di un caso.

The paper reports a case of a 16-year-old girl who was admitted to hospital in a state of shock having attempted to commit suicide by taking ten 300 mg pills of propafenone (Rytmonorm). The patient showed severe atrio-ventricular and intraventricular conduction disorders; an infusion of bicarbonate if soda and dopamine was immediately given and a temporary heart electro-stimulator was inserted. Conduction disorders gradually disappeared over the course of 36 hours and the patient was discharged with sinusal rhythm and good hemodynamic balance on the third day after admittance.

Development of kidney scars after acute uncomplicated pyelonephritis: relationship with clinical, laboratory and imaging data at diagnosis.

BACKGROUND: Acute pyelonephritis is a potential cause of kidney scars. AIM: To evaluate the relationship between clinical, laboratory and imaging data and the development of kidney scars in acute pyelonephritis. METHODS: All consecutive patients hospitalized for acute uncomplicated pyelonephritis in our nephrology unit from June 1996 to June 2004 were considered: 58 females, median age 25.6 years (16-52). Diagnosis of pyelonephritis required parenchymal lesions shown by CT or NMR scan. RESULTS: The lesions were bilateral in 17.2% (10/58) patients, unilateral, but multifocal in 81.0% (47/58); at CT or NMR, 65.5% of the lesions were classified as simple, 19% with tendency to colliquation and 15.5% abscessual. The median interval between first symptoms and diagnosis was 5 days (1-25); at referral, only 20.7% had a positive urine culture and 94.8% (55/58) had undergone previous antibiotic treatment. The therapeutic protocol required intravenous therapy for > or = 2 weeks, followed by 2-4 weeks of oral therapy. At 6-8 months, the prevalence of kidney scars was 29.3%. Their development was highly correlated with the type of lesions at diagnosis (highest risk with abscessual lesions; uni- and multivariate analysis). No other clinical or laboratory marker (age, fever, positive cultures, levels of acute phase reactants, interval between onset and diagnosis) was correlated with the outcome (scars). CONCLUSIONS: The type of lesion at diagnosis of acute uncomplicated pyelonephritis is highly correlated with the development of kidney scars. Further studies are needed to test the therapeutic schedules tailored according to the imaging data.

Captopril-enhanced scintigraphy using the method of the expected renogram: improved detection of patients with renin-dependent hypertension due to functionally significant renal artery stenosis.

UNLABELLED: PURPOSE AND DESIGN OF STUDY: Asymmetric-induced changes of the renogram under angiotensin-converting enzyme inhibition (ACE-i), i.e. lateralization, is probably the most distinctive finding for the detection of haemodynamically significant renal artery stenosis (RAS) in compensated kidney, since bilateral and symmetric patterns are non-specific. In the Consensus statement of diagnostic criteria of renovascular hypertension with captopril renography (Am J Hypertens 1991; 4: 749-755S) ACE-i-induced asymmetry of renograms for the left and right kidney was viewed as vitally important. However, detection of change in split function is a reliable parameter only when using a glomerular tracer, i.e. 99mTc-DTPA. No indication regarding a more widely used tubular tracer such as 99mTc-mercaptoacetyltriglycine (99mTc-MAG3) has been given. METHODS AND RESULTS: The theoretical contralateral curve, called 'expected renogram', was calculated frame by frame from renal curves obtained under ACE-i and one of two baseline curves. The expected renogram was compared with the recorded ipsilateral curve. More than +/- 2 SD difference between expected and recorded renograms was assumed as suggestive of monolateral or bilateral RAS. Twenty-nine patients with angiographically proven RAS (bilateral in 12) and 20 patients without arteriographic evidence of stenosis were evaluated by postcaptopril/baseline 99mTc-MAG3 renography. Results obtained with the expected renogram analysis were compared with those obtained by standard criteria which included: improvement of peak time under baseline conditions, wash-out (75%) time, and monolateral or bilateral residual cortical activity > 10%, but asymmetrical, i.e. with > 5% change in split function. Compared to the standard evaluation, the use of the expected renogram for the diagnosis of RAS improved the specificity from 70 to 95% (P < 0.03) without loss of sensitivity (79.3%). Follow-up data after revascularization were available in 18 scintigraphically positive and six scintigraphically negative patients with RAS. The sensitivity of the expected renogram method referring to short-term (1 month) patient outcome following revascularization was 88.8%. The beneficial effects on blood pressure response persisted in 77% of the these patients at 18 months. Notably, four of six scintigraphically negative patients with RAS did not show any short-term benefit from revascularization and the improvement in blood pressure values lasted for 18 months in only one case. CONCLUSIONS: The high specificity of the expected renogram method reduces the number of unnecessary invasive procedures. This is a critical point for a low-prevalence disease such as renovascular hypertension.

Scintigraphic study of ureteral peristalsis using fast Fourier transforms.

Pathophysiological changes in ureteral kinetics can be monitored externally and non-invasively by means of a time-space matrix approach during the excretory phase of fast-frame routine renography. The main limitations of this method are poor space-time resolution and, in some cases, an inadequate visualization of the peristaltic waves. A new approach to the study of ureteral contractions using the power spectrum obtained from Fourier transforms of the ureteral time-activity curves was developed. The FORTRAN program was tested by an experimental simulation, and its subsequent application on fifty-one subjects indicated that the method is a useful complement to the space-time matrix technique. Moreover, evaluation of the power spectrum offers several advantages for the study of the pathophysiological parameters of peristalsis.

Prospective study on captopril renography in hypertensive patients.

Six hundred and sixty-seven hypertensive patients were analyzed by captopril-enhanced scintigraphy. If time to reach maximal activity (Tmax) was > or = 5 min using 99mTc-diethylenetriaminepentaacetic acid (DTPA) or > or = 3 min with 123I-o-iodohippurate (OIH) and 99mTc-mercaptoacetyltriglycine (MAG3) and washout time > or = 15 min, a control study with nifedipine was performed. If the difference between Tmax under captopril and nifedipine premedication was > or = 5 min with 99mTc-DTPA or > or = 3 min with 123I-OIH and 99mTc-MAG3, the renogram was defined highly suggestive of renovascular hypertension. In the evaluation of bilateral abnormalities an additional parameter was considered, i.e. the presence of functional asymmetry of the emuntories susceptible of partial reversal in the control study under nifedipine. Based on these criteria, 58 out of 667 (8.7%) scintigrams were found to be abnormal. Thirty-five of these 58 patients and 32 of the remaining 609 scintigraphically negative cases underwent additional arteriographic examination. A renal vascular stenosis > or = 50% was found in 33 out of 35 (94.2%) patients with positive scintigraphy and in 3 out of 32 patients with negative scintigraphy. By examining results of the 67 patients undergoing arteriography, the sensitivity of captopril-enhanced scintigraphy was estimated to be 91.6%, with a specificity of 93.5%, an accuracy of 92.5%, and predictive values of a positive or negative result of 94.2 and 90.6%, respectively. By restricting analysis to bilateral stenosis, sensitivity was found to be 76.9%.(ABSTRACT TRUNCATED AT 250 WORDS)

Estimation of chromium-51 ethylene diamine tetra-acetic acid plasma clearance: a comparative assessment of simplified techniques.

Chromium-51 ethylene diamine tetra-acetic acid (51Cr-EDTA) total plasma clearance was evaluated using a multi-sample method (i.e. 12 blood samples) as the reference compared with several simplified methods which necessitated only one or few blood samples. The following 5 methods were evaluated: terminal slope-intercept method with 3 blood samples, simplified method of Bröchner-Mortensen and 3 single-sample methods (Constable, Christensen and Groth, Tauxe). Linear regression analysis was performed. Standard error of estimate, bias and imprecision of different methods were evaluated. For 51Cr-EDTA total plasma clearance greater than 30 ml.min-1, the results which most approximated the reference source were obtained by the Christensen and Groth method at a sampling time of 300 min (inaccuracy of 4.9%). For clearances between 10 and 30 ml.min-1, single-sample methods failed to give reliable results. Terminal slope-intercept and Bröchner-Mortensen methods were better, with inaccuracies of 17.7% and 16.9%, respectively. Although sampling times at 180, 240 and 300 min are time-consuming for patients, 51Cr-EDTA total plasma clearance can be accurately calculated for values greater than 10 ml.min-1 using the Bröchner-Mortensen method. In patients with clearance greater than 30 ml.min-1, single-sample techniques provide a good alternative to the multi-sample method; the choice of the method to be used depends on the degree of accuracy required.

The fate of aggregated immunoglobulin A injected in IgA nephropathy patients and healthy controls.

Organ uptake of IgA-containing immunologically active material was studied in humans by intravenous (IV) injection of 131I-labeled heat-aggregated human secretory IgA (HAS-IgA) in nine patients affected by primary IgA nephropathy and 10 normal volunteers. Aggregated secretory IgA was found to be removed almost exclusively by the liver. The peak activity in liver was reached at 21.1 minutes (range, 18 to 26 minutes) in patients and 19 minutes (range, 14 to 22 minutes) in controls. The rate of increase of liver radioactivity was found to be significantly slower in patients (with a mean slope of 5.0; range, 3.4 to 7.1 v 7.6, 5.6 to 11.4; P less than 0.02). The mean liver to precordium ratio at the peak time was significantly lower in patients (mean value, 2.3; range, 1.9 to 3.1) compared with controls (mean value, 3.3; range, 2.4 to 4.0) (P less than 0.02). These data confirm the pivotal role of the liver in the removal of aggregated IgA in humans and the defective clearance capacity of this test probe in IgA nephropathy patients.

Indium-111-labeled granulocyte head accumulation in patients with Wegener's granulomatosis.

Among the symptoms of systemic vasculitis, purulent rhinorrhea with painful sinusitis is thought to be relatively specific to Wegener's granulomatosis (WG). Sixteen patients with rapidly progressive glomerulonephritis (GN), arteritis and extensive crescents in renal biopsy were studied by head indium-111 (111In)-granulocyte scanning. They included 8 WG, 5 microscopic polyarteritis, 2 necrotizing and crescentic GN and 1 classic polyarteritis nodosa. Autologous granulocytes labeled with 12.3 MBq of 111In-oxine were administered intravenously. Scintigraphic studies were performed at 4 and 24 h post-injection. Compared to the non-WG cases, considered as a whole, significant accumulation of tracer in sinuses was observed in WG patients (Fisher's p = 0.02). Substantial scintigraphic amelioration was obtained in a WG case treated with methylprednisolone pulses and, in another WG case, after high doses of intravenous gamma-globulins. The complete disappearance of facial uptake was obtained after 2 months of intensive therapy (i.e., steroid, cyclophosphamide and plasma exchange) in another WG patient. 111In-oxine granulocyte imaging may be useful in clinical practice as an additional marker of disease activity and a tool of identification of upper respiratory tract involvement.

Colour-coded Doppler sonography in monitoring native kidney biopsies.

Two hundred and one patients had biopsies of their native kidneys with ultrasound-guided needle technique. They were evaluated on the second post-biopsy day with colour-coded Doppler sonography. Ten patients out of these 201 were found to have an arteriovenous fistula, which remained asymptomatic for the whole follow-up period (follow-ups ranged from 2 to 31 months). Four of these 10 patients developed a perirenal haematoma as well and five macroscopic haematuria. Our study shows that the systematic use of colour-coded Doppler sonography after renal biopsy facilitates diagnosis of arteriovenous renal fistula.

Angiotensin II local hyperreactivity in the progression of IgA nephropathy.

Immunologic and hemodynamic factors are likely to work in synergism in the progression of immunoglobulin A nephropathy (IgAN) toward sclerosis. The local activation of the renin-angiotensin system may be one the most relevant mechanisms. We investigated the hemodynamic effects of the acute administration of angiotensin-converting enzyme inhibitor (ACEI) (captopril 50 mg). The glomerular filtration rate (GFR) and the effective renal plasma flow (ERPF) were measured by 51Cr-EDTA and 125I hippurate clearances. The correspondent filtration fractions (FFs) in basal conditions and after administration of ACEI were calculated, then the changes in FF (delta FF and % delta FF) were determined. We studied 27 IgAN patients. Eighteen patients had normal renal function (GFR, 112 +/- 19 mL/min/1.73 m2) and nine had moderate renal impairment (GFR, 54 +/- 13 mL/min/1.73 m2). Sixteen patients had proteinuria > or = 0.5 g/d. In addition, 12 glomerulonephritis control cases and eight healthy subjects were investigated. After the administration of ACEI in healthy subjects we observed slight modifications in the GFR, a significant increase in the ERPF (P < 0.005), and a significant decrease in FF (P < 0.04). Similarly, in IgAN patients with normal renal function the GFR increased slightly, the ERPF increased significantly (P < 0.01), and there was a decrease in FF (P < 0.01). The delta FF and % delta FF values were not significantly different from those found in the controls. In patients with initial renal failure GFR remained unchanged, ERPF increased significantly (P < 0.005), and FF significantly decreased (P < 0.004). However, the changes in delta FF and % delta FF were significantly greater than those found in healthy controls (P < 0.01) and in IgAN patients with normal renal function (P < 0.001). IgAN patients with proteinuria levels > or = 0.5 g/d showed greater changes in delta FF and % delta FF after the administration of ACEI than patients with proteinuria levels lower than 0.5 g/d (P < 0.003 and P < 0.04, respectively) or proteinuric control cases (P < 0.05 and P < 0.01, respectively). This different response in proteinuric and nonproteinuric patients was evident even when the analysis was limited to the subgroup of IgAN patients with normal renal function. The decrease in FF consequent to an increase in the ERPF after the administration of ACEI suggests a local hyperactivity of the renin-angiotensin system in some cases of IgAN.(ABSTRACT TRUNCATED AT 400 WORDS)

A possible role for nitric oxide in modulating the functional cyclosporine toxicity by arginine.

The renal damage consequent to cyclosporine A (CsA) administration ranges from hemodynamic alterations to irreversible chronic lesions. The initial vasoconstriction depends upon the imbalance between the various modulators of the renal vascular tone, among which the most powerful are endothelins and nitric oxide (NO). CsA could play a crucial role by inhibiting the Ca++/calmodulin-mediated activation of the constitutive NO synthase (NOS) isoform, which converts L-arginine (L-Arg) into NO and citrulline, with a 1:1 stoichiometry. To investigate the possibility of modulating CsA nephrotoxicity with L-Arg we studied six groups (G) of Lewis rats treated with daily gavage up to eight weeks: G1, CsA 40 mg/kg; G2, G1 plus L-Arg 300 mg/kg; G3, G2 plus the competitive inhibitor of NOS, NG-nitro-L-Arg (L-NNA); G4, L-Arg alone; G5, L-NNA alone; and G6, controls receiving vehicle alone. After eight weeks L-Arg treated rats were protected against the toxic effects of CsA [creatinine (Cr) values, G2, 0.62 +/- 0.05 mg/dl vs. G1, 0.99 +/- 0.16 mg/dl, P < 0.001; proteinuria (P), G2, 7.2 +/- 1.02 mg/day vs. G1, 15.1 +/- 1.9 mg/day, P < 0.01]. The administration of L-NNA abolished the protective effect of L-Arg (G3, Cr 1.23 +/- 0.16 mg/dl; P 16.9 = 2.3; P < 0.02 and P < 0.005, respectively vs. G2). The levels of Cr in G2 rats were superimposable to control groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Interaction between the macrophage system and IgA immune complexes in IgA nephropathy.

In nine patients with IgA nephropathy, the function of the mononuclear phagocyte system was assessed by measuring in vivo clearance of anti-D coated red blood cells (RBC) and in vitro phagocytosis of sensitised RBC by monocytes. A strict correlation was found between in vivo macrophage function and in vitro monocyte phagocytosis. Statistical correlations were also found between in vivo clearance values and IgAIC and C3d values. A defective macrophage and monocyte function affects patients with major signs of clinical activity, highest IgAIC values, signs of complement activation and the most unfavourable clinical course.

Macrophage function in primary and secondary glomerulonephritis.

The function of the mononuclear phagocyte system was assessed in vivo in 85 patients with primary and secondary glomerulonephritis, by measuring the clearance of IgG - sensitised 51Cr-labelled autologous erythrocytes. Eleven per cent of patients in clinical remission were found to have a delayed clearance, whereas impaired macrophage function was present in 62.5 per cent of the patients with major urinary abnormalities. Blockade of mononuclear phagocyte system, induced at least in part by unidentified factors, might have a role in development and perpetuation of glomerular injury.

[Myocardial scintigraphy with thallium-201 in the evaluation of aortocoronary bypass patients]. / La scintigrafia miocardica con Tallio-201 nella valutazione dei pazienti operati di by-pass aorto-coronarico.

We have compared the results of 201-Thallium scintigraphy (201 TI Sc) and those of coronary angiography in 48 patients (Pts) at a mean time of 13 months after a coronary artery by-pass grafting operation (CABG). Forty-six pts were males and 2 females, with a mean age of 52 years (range 37-66). Eighteen pts (37%) had had a myocardial infarction (MI) before the operation, 4 (8%) had a perioperative and 3 (6%) a postoperative MI. Nineteen pts (40%) had angina, 9 (19%) atypical chest pain, 6 (12%) shortness of breath or easy fatigability and 14 (29%) had no symptoms. The overall CABG patency was 74% (left anterior descending: 73%, left circumflex: 71%, right coronary artery: 80%). The 201 TI was injected at peak exercise and its myocardial uptake was recorded immediately and after four hours at rest. The 201 TI Sc has shown a sensibility (SN), specificity (SP), positive predictive (PV-pos) and negative predictive value (PV-neg) of 86, 82, 64 and 94% respectively, compared to coronary angiography. In the single patient evaluation the 201 TI Sc has shown a SN, SP, PV-pos, PV-neg of 95, 85, 82 and 96% respectively versus 90, 82, 78 and 92% of the standard exercise test associated with a positive history for 1) residual angina and 2) peri or postoperative MI. The 201 TI Sc has not shown to be significantly superior to standard exercise testing and history in the evaluation of graft patency. However it allows a topographic localization of the disease which is not feasible with the latter techniques. The 201 TI Sc can better predict the patency rather than the occlusion of the grafts because there is a high number of false positives due to residual ungrafted native disease in the territory of a good functioning graft. The 201 TI scintigraphy can give a functional evaluation of borderline grafts stenoses beside the pure anatomic definition of angiography thanks to its capability to qualitatively assess the regional myocardial blood flow during stress.