Proximal internal mammary in situ graft and distal coronary-coronary graft.

When a left anterior descending coronary artery passes over the cardiac apex and presents with 2 stenoses, 1 proximal and 1 distal, the available bypass conduit often is too short to enable both the anastomosis below the distal stenosis and the sequential anastomosis on the arterial segment between the 2 stenoses. In this circumstance, we graft the internal mammary artery in situ onto the proximal segment of the left anterior descending coronary artery, then use a short residual segment of the internal mammary to perform a coronary-coronary bypass of the distal stenosis. This technique also spares segments of the internal mammary for other purposes. We present our experience, together with angiographic evidence of long-term patency.

Direct comparison of early elevations of cardiac troponin T and I in patients with clinical unstable angina.

BACKGROUND: The aim of this study was to compare the prognostic efficacy of cardiac troponin T (cTnT) and I (cTnI) in patients with clinical unstable angina. METHODS: We studied 74 patients with chest pain at rest, electrocardiographic evidence of myocardial ischemia, and normal (<6.7 ng/mL) values of creatine kinase-MB. cTnT was measured with a commercial assay (cutoff level 0.1 ng/mL) and cTnI with a preliminary research application (cutoff level 3.1 ng/mL). All patients had blood drawn at baseline and 8 hours thereafter. The prospectively defined end point was the proportion of patients identified by each assay as having myocardial damage. RESULTS: cTnT and cTnI were elevated in the same percentage of patients (18 of 74; 24%). Overall, 23 patients had elevations of 1 or both markers. In 13 there were elevations of both. Ten patients had elevations of only one (5 for each marker). In 51 patients, no elevations were present. Death or nonfatal myocardial infarction was more frequent in patients with elevated cTnI (27.7% vs 5.3%; P =.02) than those with normal values. The prognostic influence of cTnT was less (17% vs 8.5%; P =.2). However, the difference between the 2 markers when compared directly was not statistically significant (27.7% vs 17%; P = NS). CONCLUSIONS: These data indicate that both markers identify myocardial damage in equal numbers of patients with clinical unstable angina. Patients with elevations had a worse short-term outcome. The significance of the minor differences in prognostic value will require additional studies.

Prognostic influence of elevated values of cardiac troponin I in patients with unstable angina.

BACKGROUND: Elevations of the MB isoform of creatine kinase (CK) and cardiac troponin T seem to confer an adverse prognosis in unstable angina. We examined whether this prognostic influence is also present for cardiac troponin I (cTnI), a new and even more specific marker of myocardial injury. METHODS AND RESULTS: We studied 106 patients with the clinical diagnosis of unstable angina showing chest discomfort at rest within 48 hours of admission, ECG evidence of myocardial ischemia, and normal values of total CK over the initial 16 hours of observation. The primary end point was death or nonfatal myocardial infarction (MI) at 30 days; the secondary end point was the incidence of cardiac events at 1 year. Blood was drawn every 8 hours for 3 days. Thirteen patients were excluded because of increased CK-MB mass concentrations within 16 hours of admission (non-Q-wave MI) and 2 because of inadequate blood sampling. Of the remaining 91 patients, 22 had cTnI elevations on admission (n=7) or after 8 hours (n=15). At 30 days, no deaths (0%) and 4 MIs (5.8%) occurred in the 69 patients with normal cTnI compared with 2 deaths (9.1%) and 4 MIs (18.2%) in the 22 patients with elevated cTnI. The combined incidence of death and nonfatal MI was 5.8% and 27.3%, respectively (P=.02). At 1 year, only 68% of patients with elevated cTnI were free of cardiac events, compared with 90% of those without elevations (P=.01). CONCLUSIONS: These data indicate that cTnI is an important prognostic variable in patients with unstable angina. Elevations of cTnI predict an adverse short- and long-term prognosis.

The importance of antibody specificity in measuring cross-linked fibrin degradation products by ELISA.

We and others have previously shown that plasma concentrations of XL-FDPs are accurately characterized with an enzyme-linked immunosorbent assay (ELISA) based on the monoclonal antibody DD-3B6/22, which is specific for D-dimer, and a pan-specific tag antibody (DD-4D2/182) in patients with thrombotic disorders. However, in patients treated with fibrinolytic agents, increases in non-cross-linked fibrin(ogen) degradation products are detected by the pan-specific tag antibody due to formation of complexes between non-cross-linked derivatives and XL-FDPs. Assays based on the use of fibrin degradation product-specific tag antibodies appear to be more specific, but whether they would be clinically more informative is unclear. Accordingly, in the current study we measured concentrations of XL-FDPs with two ELISAs; one based on the pan-specific tag antibody (DD-4D2/182) and another based on a fibrin degradation product-specific tag antibody (DD-1D2/48) in patients treated with three well-characterized thrombolytic regimens: one associated with minimal fibrinogenolysis (100 mg tissue-type plasminogen activator [t-PA]) over 3 h), moderate fibrinogenolysis (100 mg t-PA over 90 min), and one with marked fibrinogenolysis (1.5 MU streptokinase [SK]). In patients treated with t-PA, increases in XL-FDPs were closely correlated with fibrinogenolysis, as characterized by increases in the concentration of the Bbeta1-42 peptide, when measured with the pan-specific tag ELISA (r = 0.7), but not when measured with the fibrin degradation product-specific tag assay (r = 0.2). In patients treated with SK, concentrations of XL-FDPs were significantly higher (> 2000 ng/ml) with the pan-specific tag ELISA compared with the fibrin degradation product-specific tag ELISA (< 1000 ng/ml) 1, 2 and 8 h after start of the infusion (P < 0.01). Concentrations of XL-FDPs were also higher in patients treated with SK compared with t-PA when measured with the pan-specific tag ELISA, but lower with SK with the fibrin-specific ELISA (P < 0.01). The value of measurement of XL-FDPs in patients treated with fibrinolytic agents will need to be reappraised with the use of fibrin degradation product-specific assays, which appear to provide more accurate information on the kinetics of cross-linked fibrin lysis in patients treated with t-PA or SK.

Conjunctive administration of intravenous heparin attenuates cross-linked fibrin degradation in patients treated with streptokinase.

Increases in thrombin activity occur in patients treated with streptokinase, but conjunctive therapy with intravenous heparin does not appear to improve either the rate of early infarct artery patency or survival in patients with acute myocardial infarction. In a recent study we found that concentrations of fibrinopeptide A, a marker of thrombin-mediated fibrin formation, were lower in the first 3 h in patients treated with intravenous heparin (5000 U bolus followed by a fixed-dose 1000 U/h infusion, n = 14) compared with subcutaneous (12,500 U every 12 h, started 4 h after streptokinse, n = 14) administration, but were increased in both groups of patients, consistent with persistent thrombin activity. To determine whether the differential effects of the intensity of heparinization on thrombin formation were reflected in differences in fibrin degradation, we measured cross-linked fibrin degradation products (XL-FDP) before and 1, 2, 3, 8, 12, and 24 h after streptokinase in the same cohort of patients, with a new ELISA with a D-dimer-specific capture antibody (MAb 3B6) and a fibrin-specific tag antibody (MAb 1D2, Agen, Brisbane, Australia). The incidence of early coronary recanalization assessed by creatine-kinase MM isoforms (increase in activity > or = 0.18%/min), was similar in both groups (79 vs 86%). Concentrations of XL-FDP were similar in patients with and without recanalization, but were lower in patients treated with intravenous compared with subcutaneous heparin at 8 h, but the results did not reach statistical significance (627 +/- 151 ng/ml versus 1007 +/- 157 ng/ ml, p = 0.06), and were significantly lower at 12 h (327 +/- 72 versus 781 +/- 162 ng/ml, p = 0.03 at 12 h) (mean +/- SEM). Concentrations of cross-linked fibrin degradation products were also lower in patients in whom the activated partial thromboplastin time was greater than two times the control, compared with those with inadequate anticoagulation (498 +/- 105 versus 1084 +/- 179 ng/ml; p = 0.02) (mean +/- SEM). Thus, more effective inhibition of thrombin with conjunctive intravenous heparin therapy results in less cross-linked fibrin turnover in the first 12 h after thrombolysis with streptokinase. This probably reflects decreased fibrin formation with therapeutic anticoagulation.

Non-invasive assessment of reperfusion of the infarct-related artery during coronary thrombolysis and its relation with left ventricular function.

We monitored ST segment continuously for at least 3 h after the beginning of lytic treatment in 103 patients undergoing early coronary thrombolysis for acute myocardial infarction in order to ascertain whether this technique, which has been shown to be useful to assess recanalization of the infarct-related artery, is also able to identify the improvement in left ventricular function associated with successful reperfusion. Global left ventricular function (assessed in the 30 degrees right anterior oblique projection with the area/length method) and infarct zone wall motion (studied with the centerline method) were evaluated at least 4 weeks after the event. Reperfusion was thought to be achieved when ST segment elevation dropped > 50% relative to the most abnormal peak documented at any time in the study. Eighty patients (78%) met the criterium for successful reperfusion (group 1), and 23 (22%) did not (group 2). Both groups had similar clinical and angiographic characteristics. All indexes of global left ventricular function were significantly better in group 1 than in group 2 patients (end-diastolic volume: 176 +/- 51 vs. 209 +/- 76 ml, end-systolic volume: 66 +/- 40 vs. 97 +/- 55 ml, ejection fraction: 65 +/- 13 vs. 57 +/- 11%, respectively, all P < 0.02). Also the severity (-1.6 +/- 1.3 vs. -2.6 +/- 1.01 S.D./chord, respectively, P < 0.001) and the extension of hypokinesia in the infarct zone (number of chords with > 2 S.D.: 13 +/- 16 vs. 28 +/- 17, respectively, P < 0.0001) were less in group 1 than in group 2 patients. Furthermore, in reperfused patients, both global left ventricular function and regional wall motion were better in those admitted < 60 min from onset of pain. In conclusion, patients with rapid ( > 50%) decrease of ST segment elevation have smaller infarct size and better global left ventricular function than patients without electrocardiographic signs of reperfusion as assessed by continuous ST segment monitoring. This suggests that this non-invasive technique is a powerful tool able to identify patients most benefiting from thrombolytic therapy.

Prodromal angina limits infarct size. A role for ischemic preconditioning.

BACKGROUND: In the experimental setting, it has been demonstrated that preconditioning myocardium before prolonged occlusion with brief ischemic episodes affords substantial protection to the cells by delaying lethal injury, thereby limiting infarct size. Whether the same occurs in humans remains unknown. METHODS AND RESULTS: This study was undertaken to determine whether new-onset prodromal angina, defined as chest pain episodes limited to the 24 hours before myocardial infarction, is the clinical correlate of the ischemic preconditioning phenomenon. Twenty-five patients with their first anterior myocardial infarction treated with thrombolysis (recombinant tissue plasminogen activator [r-TPA], 100 mg/3 hours) were retrospectively included in the study because they met the following criteria: (1) < 120 minutes from onset of symptoms to reperfusion therapy, (2) < 90 minutes from the beginning of thrombolytic therapy to reperfusion (defined as rapid ST elevation reduction > 50%), (3) a patient infarct-related coronary artery with TIMI 3 flow and complete absence of collateral circulation to the infarct related artery (assessed at 24 +/- 5 days), and (4) the presence of new-onset prodromal angina, ie, typical chest pain episodes occurring at rest within 24 hours or, alternatively, a complete absence of symptoms before onset of infarction. Therefore, on the basis of their clinical status before infarction, the patients were divided into two groups: group 1, 13 patients without prodromal angina, and group 2, 12 patients with prodromal angina. Despite no difference in time to treatment (81 +/- 19 versus 75 +/- 21 minutes in group 1 and group 2, respectively; P = NS) and time to reperfusion (58 +/- 34 versus 46 +/- 24 minutes; P = NS), the peak of CKMB release was markedly lower in group 2 (86.3 +/- 66 versus 192.3 +/- 108.3 IU/L; P < .01). In addition, although both groups were comparable in terms of area at risk (amount of myocardium beyond the infarct-related stenosis; 15.1 +/- 4.6 versus 13.7 +/- 4.6 hypokinetic segments in group 1 and group 2, respectively, P = NS), the final infarct size (11 +/- 7.5 versus 5.6 +/- 4 hypokinetic segments, P < .04) was smaller in group 2. Thus, the limitation of the infarct size was significantly greater in group 2 (69% versus 36%; P < .05), and this represents an additional 33% reduction (95% confidence intervals, 7.1% to 58.9%; P = .01) in the group of patients with prodromal angina. Also, the third index, that is, the ECG, showed a favorable trend toward a lesser number of Q waves and a higher sigma R waves, although the values did not reach statistical significance. CONCLUSIONS: Despite a similar area at risk, patients with new-onset prodromal angina showed a significantly smaller infarct size compared with patients without prodromal symptoms. Since the two groups had similar times to reperfusion and no evidence of collateral circulation to the infarct related artery, the protection afforded by angina in group 2 patients might be explained by the occurrence of ischemic preconditioning.

Failure of fixed dose intravenous heparin to suppress increases in thrombin activity after coronary thrombolysis with streptokinase.

OBJECTIVES: This study was designed to define the extent of inhibition of thrombin activity achieved with conjunctive fixed dose intravenous sodium heparin compared with fixed dose subcutaneous calcium heparin in patients receiving intravenous streptokinase for acute myocardial infarction. BACKGROUND: The role of heparin therapy during coronary thrombolysis with streptokinase is controversial, in part because the efficacy of different conjunctive heparin regimens in inhibiting early increases of thrombin activity is not known. METHODS: Twenty-eight patients treated with 1.5 million U of streptokinase and 165 mg of aspirin for acute myocardial infarction were randomly assigned to receive fixed dose subcutaneous heparin therapy (12,500 U every 12 h delayed until 4 h after the end of streptokinase therapy [n = 14]) or fixed dose intravenous heparin (5,000-U bolus followed by 1,000-U/h infusion [n = 14]). Anticoagulation was assessed with serial measurements of activated partial thromboplastin time, and thrombin activity by measuring fibrinopeptide A and thrombin-antithrombin III complex levels. Plasma concentrations of creatine kinase (CK) MM isoforms were measured for 3 h to determine recanalization (increase in activity > 0.18%/min). RESULTS: Recanalization occurred in 27%, 64% and 79% of patients given subcutaneous heparin versus 43%, 76% and 86% of those given intravenous heparin at 1, 2 and 3 h, respectively (p = 0.6). Concentrations of fibrinopeptide A (mean +/- SEM) at 1 h were higher in patients without (n = 5) than in those with (n = 23) CK-MM isoform criteria for recanalization (76.4 +/- 25.7 vs. 25.2 +/- 5.2 nmol/liter, p = 0.02), and at 1, 2 and 3 h were significantly lower with fixed dose intravenous heparin (18.4 +/- 4.8 vs. 46.7 +/- 10.2 nmol/liter at 1 h, p = 0.004) than without heparin. After fixed dose subcutaneous heparin at 4 h, fibrinopeptide A levels were similar in both groups despite lower activated partial thromboplastin times in patients who received fixed dose subcutaneous heparin. However, fibrinopeptide A was not consistently suppressed in either group (fixed dose subcutaneous heparin 8.7 +/- 1.8 nmol/liter vs. fixed dose intravenous heparin 11.8 +/- 5.2 nmol/liter) at 48 h (p = 0.4). No significant changes in the concentration of thrombin-antithrombin III complexes were found between the two groups. CONCLUSIONS: Fixed dose intravenous heparin attenuates increases in fibrinopeptide A early after streptokinase. Subsequent fixed dose intravenous and subcutaneous heparin have similar effects but are relatively ineffective in suppressing thrombin activity, suggesting a role for more potent antithrombin agents during coronary thrombolysis with streptokinase.

Concurrent nitroglycerin therapy impairs tissue-type plasminogen activator-induced thrombolysis in patients with acute myocardial infarction.

Nitroglycerin given with tissue-type plasminogen activator (t-PA) has been shown to decrease the thrombolytic effect of t-PA in animal models of coronary artery thrombosis. The present study was conducted to determine whether such an interaction between nitroglycerin and t-PA occurs in patients with acute myocardial infarction undergoing thrombolytic treatment. Patients with acute myocardial infarction were treated with t-PA plus saline solution (group 1; n = 11) or t-PA plus nitroglycerin (group 2; n = 36). Stable coronary artery reperfusion assessed by continuous ST-segment monitoring in 2 electrocardiographic leads, and release of creatine kinase occurred in 91% of group 1 patients and in 44% of group 2 patients (95% confidence interval, 14% to 82%; p < 0.02). Plasma levels of t-PA antigen were consistently (p < 0.005) higher in group 1 than in group 2 patients up to 6 hours after t-PA infusion. Conversely, plasminogen activator inhibitor-1 (PAI-1) levels were slightly higher in group 2 than in group 1 patients. These observations indicate that nitroglycerin given with t-PA significantly decreases the plasma t-PA antigen concentrations and impairs the thrombolytic effect of t-PA in patients with acute myocardial infarction.

[Echocardiographic study of left ventricular function using automated border detection in normal subjects]. / Studio ecocardiografico della funzione ventricolare sinistra mediante automated border detection in soggetti normali.

BACKGROUND: Two-dimensional (2D) echocardiographic automated border detection (ABD) can provide on-line measurement of left ventricular cavity area and fractional area change. However, this new quantitative method has not been extensively validated. METHODS: Values of manually traced areas on 2D-echo images were compared with those obtained from ABD in 34 consecutive normal subjects (age 16-65 years). Only subjects with more than 70% of endocardial border circumferences clearly seen in both selected imaging planes were included in the study. We evaluated left ventricular end-diastolic and end-systolic area, and fractional area change obtained from mid-left ventricular short axis and apical 4-chamber view. Left ventricular volumes (area/length method) and ejection fraction were manually calculated off-line from apical 4-chamber view. RESULTS: From the short axis view, left ventricular cavity area measurements with ABD were obtained in 85% of subjects. The values closely correlated with off-line measurements: end-diastolic area 15.6 +/- 3.1 vs 14.8 +/- 3.3 cm2, r = 0.88 SEE = 1.58; end-systolic area 7.2 +/- 1.7 vs 6.7 +/- 1.7 cm2, r = 0.88 SEE = 0.80. A good correlation was also found for the apical 4-chamber view; end-diastolic area 25.9 +/- 5.9 vs 25.3 +/- 5.5 cm2, r = 0.97 SEE = 1.36; end-systolic area 16.3 +/- 4.1 vs 15.0 +/- 3.8 cm2, r = 0.92 SEE = 1.51. In this view ABD measurements were obtained in 79% of subjects. A significant correlation was also found between the end-diastolic volume and short axis (r = 0.54, SEE = 2.63; p 0.003) and apical 4-chamber (r = 0.66, SEE = 4.51; p = 0.0002) ABD diastolic area. Similarly, the end-systolic volume was significantly correlated with short axis (r = 0.57, SEE = 1.42; p = 0.001) and apical 4-chamber (r = 0.55, SEE = 3.54; p = 0.003) ABD systolic area. However, the on-line fractional area change correlated with off-line ejection fraction better from short axis view: (r = 0.72 SEE = 3.52) than from apical 4-chamber view (r = 0.45 SEE = 6.84). CONCLUSIONS: These data indicate that: 1) left ventricular areas measured by ABD correlate well with manually measured areas and volumes; 2) short axis ABD fractional area change may be a reliable substitute of off-line manually traced ejection fraction in normal subjects.

Patency of the infarct-related artery and left ventricular function as the major determinants of survival after Q-wave acute myocardial infarction.

One hundred seventy-two patients with 1-vessel disease documented at predischarge angiography who had been followed for 43 +/- 30 months after an initial Q-wave acute myocardial infarction were retrospectively evaluated to investigate the prognostic value of infarct-related artery patency and left ventricular (LV) function. Multiple logistic regression analysis revealed that only infarct artery patency (Thrombolysis in Myocardial Infarction [TIMI] grades 2-3 vs 0-1) (Z = 2.24; p < 0.05) and end-systolic volume index (Z = -2.67; p < 0.01) were independently related to survival. Sixteen cardiac deaths were observed; all 16 patients had LV dysfunction (defined as end-systolic volume index > 40 ml/m2), and 15 had an occluded infarct-related artery. In the subgroup with LV dysfunction, the 10-year percent survival rate was 20% among patients with TIMI grade 0 to 1 versus 96% with grade 2-3 (p < 0.001). Patency of the infarct-related artery was also the only independent predictor of recurrent ischemia (Z = 2.59; p < 0.01). In conclusion, both infarct-related artery patency and LV function are independent predictors of survival after Q-wave acute myocardial infarction. Patients with normal LV function have an excellent long-term prognosis, which is only partially counterbalanced by the tendency toward clinical instability observed in those with an open infarct-related vessel. However, when an occluded infarct-related artery is observed in the setting of LV dysfunction, the long-term outcome appears to be relatively poor.

Left ventricular dynamics after aortic valve replacement: a long-term, combined radionuclide angiographic and ultrasonographic study.

Between January 1985 and July 1990, we studied 71 patients at our institution who underwent aortic valve replacement for either aortic valve regurgitation (40 patients) or stenosis (31 patients). The following prostheses were implanted: 25 St. Jude Medical valves (bileaflet), 16 Björk-Shiley (monoleaflet, tilting disc, 60 degrees convexo-concave), 16 Medtronic-Hall (monoleaflet, tilting disc), and 14 Starr-Edwards (caged ball). The patients were evaluated pre-and postoperatively by means of gated blood-pool scintigraphy and Doppler echocardiography. Postoperatively, each patient was studied at 6 months, 1 year, and then annually. The evaluations focused upon 1) scintigraphically assessed left ventricular performance indicators (end-diastolic and end-systolic volume, as well as resting and exercise ejection fraction) and 2) Doppler-derived hemodynamic indexes (peak and mean transvalvular pressure gradient, effective orifice area, regurgitant flow, and systolic wall stress). Early after aortic valve replacement, 55 (77.5%) of the patients had substantial symptomatic relief, with normal hemodynamic values both at rest and during exercise (New York Heart Association functional class I or II); another 6 patients (8.5%) maintained their preoperative status in those classes. Within a year after surgery, a majority of patients showed a significant reduction in left ventricular dimensions. The patients with preoperative aortic valve stenosis had a significantly reduced end-diastolic and end-systolic volume (p<0.05), a moderately reduced left ventricular mass index (p<0.01), and a significantly increased exercise ejection fraction (p<0.05); moreover, in all 31 of these cases, systolic wall stress returned to normal or lower-than-control values (p<0.005). The patients with preoperative aortic valve regurgitation had a significant reduction in end-diastolic and end-systolic volume (p<0.005), diastolic wall stress (p<0.005), and a significant increase in exercise ejection fraction (p<0.01); however, their left ventricular mass index was not significantly reduced. Optimal long-term survival was afforded by the St. Jude valve in the small size (21 mm) and the Starr-Edwards valve in the large size (27 mm). This study represents the first reported use of a serial, combined radionuclide and echocardiographic procedure for the follow-up of patients undergoing aortic valve replacement. During the 5(1/2)-year follow-up period, this combined technique proved highly accurate for collecting follow-up data, often complementing or correcting simple ultrasound results. This diagnostic approach enabled us to 1) obtain information comparable to or better than that provided by cardiac catheterization, 2) identify complications early, 3) differentiate between valvular and ventricular failure, and 4) suggest the valve of choice (not always that with the best hemodynamic performance) in patients with different cardiac variables. Further research is needed to confirm this study, the results of which could change many medical and surgical strategies for clinical management of the diseased aortic valve.

[Doppler ultrasound in the diagnosis of renal artery stenosis in hypertensive patients: a prospective study]. / L'eco-Doppler per la diagnosi di stenosi dell'arteria renale in pazienti ipertesi: studio prospettico.

Renal artery stenosis is the most common surgically or interventionally curable cause of hypertension. Screening and diagnostic tests are still needed to establish the presence of renal artery stenosis. The aim of our study was to evaluate sensitivity, specificity and diagnostical accuracy of renal artery duplex scanning for diagnosis of renal artery stenosis in hypertensive patients. Between January 2, 1988 and December 31, 1989 we performed renal artery duplex scanning in 128 hypertensive patients in whom were present clinical data suggestive of renal artery stenosis. Angiographic evaluation was performed within 3 months in 23 patients with a positive duplex, and in 15 patients with a negative duplex but highly suggestive for renal artery stenosis clinical data. Studies were performed with an Ultramark 8 duplex scanner (ATL). Data of this report are relative to the analyses performed of 76 renal arteries. Duplex scanning had a sensitivity of 90% and specificity of 96% to detect renal artery stenosis. Diagnostic accuracy was 93% for 50% to 60% stenosis and 100% for occlusion or 60% to 99% renal artery stenosis. Duplex scanning for diagnosis of renal artery stenosis shows agreement with angiography. Duplex scanning, which can distinguish high grade stenosis from occlusion, is able to select patients for possible percutaneous transluminal angioplasty before angiography, and we consider duplex scanning a valid, noninvasive screening or diagnostic test for renovascular hypertension.

[Comprehensive computer-assisted management of a cardiology department]. / Informatizzazione completa di una divisione di cardiologia.

We are proposing a personal computer local network system for collecting data and managing of both cardiovascular in- and outpatients. The six PCs used as work stations are located in the following areas: reception desk, ergometry, holter, echocardiography, secretarial and coronary care unit and cardiology department. Starting from a commercially available DBMS program, an "Iceberg" applied program was first made in a single personal computer and then transferred to a local network. The tree-structured data base includes the cardiopathies list, the vasculopathies list, some cardiovascular clinical data and all information regarding cardiological instrumental tests. The data are descriptive, numeric, date, text and comment. The operative program allows us to change the data base without the help of the software house staff, so the system is adaptable to cardiological departments with different instrumental equipment and sections. The report of instrumental tests and the issuing of the discharge letter are made with the local work station, with simultaneous compiling, storing and printing. It is then possible, using any work station, to restore and print quickly a summary of all data concerning each patient. This summary permits us, in nearly all cases, to identify the patient's history and present condition, as well as the diagnostical steps taken.

Doppler hemodynamic characteristics of four widely used aortic valve prostheses.

Fifty-one patients with normofunctioning aortic prosthetic heart valves were evaluated by Doppler-Echocardiography to determine type-related flow characteristics. The four mechanical valves tested were: Starr-Edwards (1200-1260 aortic), Bjork-Shiley (60 degrees-60 degrees cc aortic), Medtronic-Hall (aortic) and St. Jude Medical (aortic). The most significant dynamic indexes were calculated: Peak (PG) and Mean (MG) Gradient across the valve, Cardiac Index (CI) or Cardiac Output (CO), Regurgitant Jets, Effective Orifice Area (EOA), Spectral Diagram Systolic Trend (SDST) and PVRT (time required to reach peak velocity during systole)/LVET (left ventricular ejection time) Ratio. Patients with Doppler assessed prosthetic dysfunction were dropped out of the study group. As expected, significant reverse correlation (-0.70) was found when transvalvular pressure gradients were compared with valve size. Significant direct correlation (0.82) was found when EOA was compared with valve size, thus suggesting the high reliability of the continuity equation in the assessment of the real orifice area. The Starr-Edwards valve, when compared with the other prostheses of the same size, showed the highest calculated transvalvular gradient; the St. Jude Medical showed the lowest. On the other hand, the Starr-Edwards valve was not commonly associated with regurgitation, while the St. Jude valve was usually moderately incompetent. Those hemodynamic differences should guide the selection of the ideal prosthetic valve for elective surgical indications. Doppler measurements provided noninvasive information similar to that given by cardiac catheterisation, which was reproducible and specific for valve function. According to this high sensitivity and specificity and to the absolute innocuity of the procedure, Doppler-Echocardiography should be considered the elective technique for long-term follow-up in patients with aortic prosthetic heart valves.

[Value of metabolic studies in diagnosis of ischemic cardiopathy]. / Valore dello studio metabolico nella diagnostica della cardiopatia ischemica.

10 patients with documented heart disease were undergone to atrial pacing (AP) combined to metabolic study. A negative lactate utilization (-%L) noticed in SC (coronary synus) represents a sure proof of a subordinate pacing ischaemia. As the negative lactate utilization is absent a significative reduction of %L during AP or its persistence in recovery and a rise of L/P are further parameters of a subordinate pacing ischaemia. The Authors consider the usefulness of combining a metabolic study to AP in assessing the RC (coronary reserve).

[Malfunction of disc prostheses. Echocardiographic study of 5 cases (author's transl)]. / Malfunzionamento di protesi a disco. Studio ecocardiografico di cinque casi.

78 patients who underwent disc prostheses replacement, 36 in mitral area, 58 in aortic area were studied by echocardiography. The Authors found 5 cases of malfunction, 3 in mitral area and 2 in aortic area. Regarding mitral malfunctions in 1 case a valve thrombosis was found; in 2 cases there was a partial leak. Regarding aortic malfunctions there was paravalvular leak. In mitral area malfunctions the Authors found alterations of the disc morphology during diastolic opening time associated with alteration of opening time. An increased diastolic closure velocity in 2 cases of paraprosthetic leak was found. A diagnostic element in the case with thrombosis was variability of maximal disc escursion during the same recording, because opening time variability never got over 10 m. seconds. In aortic area malfunctions the Authors found a constant fluttering of anterior mitral leaflet, a sinergic septal motion with the posterior wall and in 1 case the presence of disc opening before the first component of the first sound. The Authors underline the importance of simultaneous eco-phonocardiographic examination and the check-ups for the time to be.

[Electrophysiological evaluation of the aberrant pathways of intraventricular conduction obtained by means of premature atrial stimulation]. / Valutazione elettrofisiologica delle aberranze della conduzione intraventricolare ottenute mediante stimolazione atriale prematura.

12 patients with normal QRS either in basal condition or during atrial pacing, undergone on single premature atrial stimulation, showed several types of intraventricular aberrancies. These have been revalued with atrial premature stimulation introduced over a progressively increasing frequency of fixed atrial stimulation (extrastimulus method), sometimes after atropine. In 9 cases it was possible to eliminate completely the above mentioned aberrancies, having thus a clear reduction of the refractory periods regarding their responsible structures. In 3 cases this was not possible, owing to a less significant reduction of the refractory periods. Such fenomenon is considered as the only parameter able to identify probable initial organic facts of the His-Purkinje system.