Lack of agreement between left ventricular volumes and ejection fraction determined by two-dimensional echocardiography and contrast cineangiography in postinfarction patients.

OBJECTIVE: To assess the agreement between left ventricular (LV) volumes and ejection fraction (EF) determined by two-dimensional echocardiography (2-D echo) and by cineangiography in postinfarction patients. DESIGN: LV end-diastolic and end-systolic volumes indexed (EDVI and ESVI) to body surface area as well as EF were determined by both methods in all patients. SETTING: Multicenter trial conducted in five university hospitals. PATIENTS: 63 patients, 61 male, two female, mean age 55.5 +/- 10.4 years, suffering from a recent myocardial infarction. Eighty-one pairs of measurements were available. METHODS: The results of biplane 2-D echo measures, using apical four-chamber (4C) and two-chamber (2C) views were compared to those of a 30 degrees right anterior oblique cineangiography projection, using either the apical method of discs or the area-length 2-D echo method. Moreover, eyeball EF was estimated at 2-D echo and cineangiography, and was compared to the conventional methods. The agreement between results was assessed by the Bland and Altman method. RESULTS: The agreement between 2-D echo and cineangiography results was poor. Mean differences (MD) were -21.8 (EDVI, ml/m(2)), -9.5 (ESVI, ml/m(2)), and -0.9 (EF, %), respectively for 2-D echo method of discs versus cineangiography, and -23.2, -9.3, and -5.7 for area-length 2-D echo versus cineangiography. For EF (%), MD was -3.6 for eyeball cineangiography versus cineangiography, -1.3 for eyeball 2-D echo versus method of discs, and +0.30 for eyeball 2-D echo versus area-length 2-D echo, respectively. Two-dimensional echo is likely to underestimate LV volumes compared to cineangiography, especially for largest volumes. Even for EF, discrepancies are large, with a lack of agreement of 21%-25% between conventional methods, but agreement is better between eyeball EF and usual methods. CONCLUSIONS: Even with modern echocardiographic devices, agreement between 2-D echo and cineangiography-derived LV volumes and EF remains moderate, and both methods must not be considered interchangeable in clinical practice.

Warm reperfusion and myocardial protection.

BACKGROUND: The aim of this study was to determine whether warm reperfusion improves myocardial protection with cardiac troponin I as the criteria for evaluating the adequacy of myocardial protection. METHODS: One hundred five patients undergoing first-time elective coronary bypass surgery were randomized to one of three cardioplegic strategies of either (1) cold crystalloid cardioplegia followed by warm reperfusion, (2) cold blood cardioplegia followed by warm reperfusion, or (3) cold blood cardioplegia with no reperfusion. RESULTS: The total amount of cardiac troponin I released tended to be higher in the cold blood cardioplegia with no reperfusion group (3.9+/-5.7 microg) than in the cold blood cardioplegia followed by warm reperfusion group (2.8+/-2.7 microg) or the cold crystalloid cardioplegia followed by warm reperfusion group (2.8+/-2.2 microg), but not significantly so. Cardiac troponin I concentration did not differ for any sample in any of the three groups. CONCLUSIONS: Our study showed that the addition of warm reperfusion to cold blood cardioplegia offers no advantage in a low-risk patient group.

Reproducibility of bipolar endocavitary electrogram measurements at sites of radiofrequency energy delivery in patients with the Wolff-Parkinson-White syndrome.

BACKGROUND: Radiofrequency ablation of atrioventricular accessory pathway is widely used to cure patients with the Wolff-Parkinson-White syndrome. The site of successful ablation is determined using electrophysiological parameters, endocavitary bipolar electrogram measurements being the most commonly used. Interobserver reproducibility of these measurements may limit the reliability of ablation criteria based upon bipolar measurements only but, to our knowledge, this reproducibility has not been evaluated so far. Such was the aim of this study. METHODS: Three independent observers reviewed the bipolar electrograms recorded at sites were radiofrequency energy was delivered (successfully or not) in 28 consecutive patients with the Wolff-Parkinson-White syndrome. In each tracing, 4 intervals were measured: (1) A0V0 (onset of the atrial electrogram to onset of the ventricular electrogram), (2) AaVa (activation time of the atrial electrogram to activation time of the ventricular electrogram), (3) V0-QRS (onset of the ventricular electrogram to onset of delta wave on the surface ECG) and (4) Va-QRS (activation time of the ventricular electrogram to onset of delta wave on the surface ECG). RESULTS: The interobserver reproducibility was low since only 50% of A0V0 intervals were measured with an interobserver difference lower than 10 ms and up to 43% of Va-QRS intervals were measured with an interobserver difference greater than 30 ms. The reproducibility of interval measurement was graded from the highest to the lowest as follows: A0V0, AaVa, V0-QRS and Va-QRS (Chi-square statistic, chi 2 = 71.72, p < 0.0001). Kappa values were lower than 0.40, indicating a poor interobserver reproducibility. CONCLUSIONS: Our study suggests that interobserver reproducibility of only bipolar electrograms interval measurements at sites of radiofrequency ablation of atrioventricular accessory pathway is poor, which limits the reliability of bipolar criteria to predict a successful ablation site.

Planimetry of aortic valve area using multiplane transoesophageal echocardiography is not a reliable method for assessing severity of aortic stenosis.

OBJECTIVE: To assess the reliability of aortic valve area planimetry by multiplane transoesophageal echocardiography (TOE) in aortic stenosis. DESIGN: Study of the diagnostic value of aortic valve area planimetry using multiplane TOE, compared with catheterisation and the continuity equation, both being considered as criterion standards. SETTING: University hospital. PATIENTS: 49 consecutive patients (29 male, 20 female, aged 44 to 82 years, average 66.6 (SD 8.5)), referred for haemodynamic evaluation of an aortic stenosis, were enrolled in a prospective study. From this sample, 37 patients were eligible for the final analysis. METHODS: Transthoracic and multiplane transoesophageal echocardiograms were performed within 24 hours before catheterisation. At transthoracic echo, aortic valve area was calculated by the continuity equation. At TOE, the image of the aortic valve opening was obtained with a 30-65 degrees rotation of the transducer. Numerical dynamic images were stored on optical discs for off-line analysis and were reviewed by two blinded observers. Catheterisation was performed in all cases and aortic valve area was calculated by the Gorlin formula. RESULTS: Feasibility of the method was 92% (48/52). The agreement between aortic valve area measured at TOE (mean 0.88 (SD 0.35) cm2) and at catheterisation (0.79 (0.24) cm2) was very poor. The same discrepancies were found between TOE and the continuity equation (0.72 (0.26) cm2). TOE planimetry overestimated aortic valve area determined by the two other methods. Predictive positive and negative values of planimetry to detect aortic valve area < 0.75 cm2 were 62% (10/16) and 43% (9/21) respectively. CONCLUSIONS: Planimetry of aortic valve area by TOE is difficult and less accurate than the continuity equation for assessing the severity of aortic stenosis.

[Long-term outcome of subvalvular aortic stenoses. A comparative study in adults and children]. / Evolution à long terme des sténoses sous-valvulaires aortiques. Etude comparative chez les adultes et les enfants.

The aim of the study was to determine the medium and long-term outcome of discrete subaortic stenosis after surgery: the data of two groups of patients classified according to age (children versus adults) at the time of diagnosis were compared retrospectively. Sixteen patients, with subaortic stenosis, were followed up clinically and by annual echocardiography for an average period of 5.7 +/- 3.6 years (range 1 day to 16 years) and patients in group II were aged 43.6 +/- 6 years (range: 3 to 17 years). Patients in group I were aged 5.4 +/- 4.2 years (range: 37 to 53 years). Four patients from group II had significant aortic incompetence. All but one patient had a membranous stenosis. Seven patients from group I and all in group II underwent surgery during the follow-up period. Four of the 5 adults in Group II were asymptomatic compared with only 1 in group I. Three patients of group II developed left ventricular dysfunction during the preoperative period compared with none in group I. Four patients in group II underwent aortic valve replacement compared with none in group I. Four of the 7 operated patients in group I had recurrence of subaortic stenosis, one of which was a tunnel form. Two reoperations were necessary in group I. There were no recurrences in group II. In conclusion, the poor outcome of adult subaortic stenosis has led to early surgical referral. This attitude should be nuanced in view of the risk of recurrence and of reoperation in childhood.

[Anticoagulant therapy with recombinant hirudin in patients with thrombopenia induced by heparin]. / Traitement anti-thrombique par hirudine recombinante chez des patients ayant une thrombopénie induite par l'héparine.

OBJECTIVES: Heparin-induced thrombocytopenia is an uncommon and severe complication of heparin therapy. Both venous and arterial thromboembolic events can occur, requiring withdrawal of the heparin therapy. When anticoagulant therapy is mandatory, recombinant hirudin can be used. METHODS: We used recombinant hirudin (HBW 023) in 6 patients with heparin induced thrombocytopenia. In case of venous thromboembolism, an initial intravenous bolus (0.07 mg/kg) was followed by continuous infusion (0.05 mg/kg/h); for arterial thromboembolism the initial bolus was 0.7 mg/kg and infusion rate 0.15 mg/kg/h. When possible oral anticoagulants were started and hirudin withdrawn when the INR ratio reached 3. RESULTS: The clinical course was uneventful in all 6 patients. There was no recurrent thromboembolism. Cephalin-activated coagulation time (patient/control) varied between 1.8 and 3.5 (median 2.4) during hirudin administration. Platelet count rose to the nadir (median 70 x 10(9)/l, range 15-90) reaching over 100 x 10(9)/l in all patients between the third and sixth day (median 5 days) after stopping heparin. CONCLUSION: Intravenous administration of hirudin provides effective immediate anticoagulation in patients with heparin-induced thrombocytopenia, thus allowing conversion to oral anticoagulants without risking recurrent thromboembolism.

Use of recombinant hirudin as antithrombotic treatment in patients with heparin-induced thrombocytopenia.

Heparin-induced thrombocytopenia is a rare but severe complication of heparin therapy that can result in severe venous or arterial thromboembolic events and whose treatment remains partially unanswered. Recombinant hirudin is potentially effective as an antithrombotic treatment in the management of heparin-induced thrombocytopenia, given its potent antithrombin effects without known interaction with platelets. We report the results obtained with intravenous recombinant hirudin (HBW 023) administered on a compassionate basis to patients suffering from heparin-induced thrombocytopenia. Six patients suffering from heparin-induced thrombocytopenia were submitted to intravenous recombinant hirudin (HBW 023) administered at a dose of 0.05 mg/kg/hr after an initial bolus injection of 0.07 mg/kg in the case of a venous thromboembolic event, and at a dose of 0.15 mg/kg/hr with the same initial bolus injection in the case of an arterial thromboembolic event. Whenever possible, oral anticoagulation with acenocoumarol was introduced at the same time as recombinant hirudin, which was interrupted as soon as the international normalized ratio reached 3. Clinical events, particularly thromboembolism and bleeding, were noted; activated partial thromboplastin time (aPTT), and platelet count were assessed throughout the administration of recombinant hirudin. Heparins responsible for heparin-induced thrombocytopenia were porcine sodium or calcium heparinate in four cases, nadroparin in one case, and enoxaparin in one case. Thrombocytopenia was discovered on routine systematic platelet count in two patients and after the occurrence of arterial and venous thromboembolism in two patients, respectively. After discontinuation of heparin and the onset of recombinant hirudin, clinical evolution was uneventful in all patients, with no recurrence of thromboembolism, limb amputation, or hemorrhagic complication. The aPTT ratio varied from 1.8 to 3.5 (median 2.4) throughout administration of recombinant hirudin. Platelet count rose from nadir (median value 60 x 10(9), 15 to 90) to above 100 x 10(9)/L in every patient within 3-6 days (median 5), after discontinuation of heparin. Intravenous administration of recombinant hirudin ensured safe anticoagulation in patients with heparin-induced thrombocytopenia and made it possible to wait for oral anticoagulation to become efficient and platelet count to return to normal values without occurrence or recurrence of thromboembolism.

[Efficacy and safety of thrombolytic therapy in the elderly with severe pulmonary embolism]. / Efficacité et sécurité d'emploi du traitement thrombolytique chez les sujets âgés avec embolie pulmonaire grave.

Thrombolytic therapy leads to more rapid dissolution of thrombi in severe pulmonary embolism than conventional heparin therapy but is considered with much reserve in elderly patients because of the risk of haemorrhage, which is thought to be potentially greater in these subjects. The object of this study was to assess the efficacy and safety of thrombolytic therapy in patients over 70 years of age with severe pulmonary embolism, compared with patients under 70 years of age with the same condition. Eighty-nine patients with severe pulmonary embolism (Miller score > 17/34) were prescribed thrombolytic therapy in the absence of a contraindication without taking age into consideration. Fifty-three were under 70 years of age (54 +/- 15; range: 18 to 70 years) and 36 were over 70 years of age (78 +/- 5; range: 71 to 88 years). Apart from age, there was no difference in the clinical presentation of the two groups. Thrombolytic therapy was initiated with streptokinase 100,000 IU/hr for twelve hours after an initial bolus of 250,000 IU or with urokinase or plasminogen tissue activator in cases with a contraindication to streptokinase. An uncomplicated course was observed in the same percentage of cases in the two groups. The Miller score and mean pulmonary pressures fell in the same way in the two groups. Three patients died during the hospital period, two aged under 70 (3.7%) and one over 7 years of age (2.7%). Major bleeding occurred in 3 subjects under 70 (5.6%) and 5 subjects over 70 (13.8%) (p = 0.29).(ABSTRACT TRUNCATED AT 250 WORDS)

[Complications of percutaneous mitral valvuloplasty; comparison of the double balloon and the Inoue techniques]. / Complications de la valvuloplastie mitrale percutanée; comparaison entre technique du double ballon et technique d'Inoue.

Percutaneous mitral valvuloplasty is a non-surgical procedure for treating mitral stenosis. There are two techniques of performing this procedure, the double balloon and the Inoue techniques. The aim of this study was to compare the immediate complications of percutaneous mitral valvuloplasty in two consecutive series of unselected patients undergoing the double balloon (131 patients) and the Inoue (131 patients) techniques. The two series were comparable before valvuloplasty with respect to demographic, clinical, echocardiographic and haemodynamic criteria. The increase in valvular surface area and the decrease in pressure gradient after valvuloplasty were not significantly different (1.1 +/- 0.2 to 1.95 +/- 0.5 cm2 in the Inoue series and 1.0 +/- 0.2 to 1.95 +/- 0.5 cm2 in the double-balloon series; 12 +/- 3 to 5 +/- 2 mmHg in the Inoue series and 13 +/- 4 to 5 +/- 2 mmHg in the double-balloon series for the mean transvalvular pressure gradient). A good immediate result was defined as a valve surface are > 1.5 cm2 and < or = 2 + mitral regurgitation after the series, and this was obtained in 78% of cases in both series. Severe mitral regurgitation (3 +) requiring immediate or elective mitral valve replacement was observed in 7 cases in the Inoue series and in 5 cases in the double-balloon series (NS). One cerebral embolism occurred in the double balloon series and two systemic embolisms, one cerebral and one coronary, in the Inoue series.(ABSTRACT TRUNCATED AT 250 WORDS)

[Cardiovascular pathology and magnesium]. / Pathologie cardiovasculaire et magnésium.

There is no univocal clinical cardiovascular pattern associated with magnesium deficiency. Only an acute hypomagnesaemia gives the evidence of a real magnesium deficiency. Arrhythmias corrected by magnesium are associated with potassium deficiency. Magnesium deficiency appears to be one risk factor of arrhythmias and coronary spasms. The influence of intravenous magnesium salts was clearly evaluated on cardiovascular electrophysiology allowing protocols infusion. The major beneficial effect of magnesium on total incidence of arrhythmias appears to have been due to a reduction in supraventricular tachyarrhythmias and especially in "torsade de pointes". Antiarrhythmic mechanisms still remain to be clarified. It is likely that magnesium influences cardiac conduction and refractoriness by affecting calcium dependent processes as if acting as an indirect inactivator of slow inward calcium current, probably secondary to an inward shift of the background potassium mediated current. Recent studies demonstrated beneficial effect of intravenous magnesium treatment in acute myocardial infraction, both as to mortality and to early cardiac insufficiency. Beside antiarrhythmic and vasodilatator effects, magnesium seems to show cardiac cells protective action against ischaemia.

Safety of thrombolytic therapy in elderly patients with massive pulmonary embolism: a comparison with nonelderly patients.

OBJECTIVES: The aim of the study was to prospectively estimate the safety of thrombolytic therapy in elderly patients with massive pulmonary embolism in comparison with that in nonelderly patients. BACKGROUND: In massive pulmonary embolism, lysis of thrombi can be achieved faster with thrombolytic therapy than with conventional heparin therapy, but it is administered with great caution in elderly patients because the risk of bleeding is thought to be higher than in nonelderly patients. Yet, thrombolytic therapy might be of value in elderly patients also, in allowing potentially more rapid improvement than is achieved with conventional heparin therapy. METHODS: Eighty-nine patients with massive pulmonary embolism defined as Miller score > or = 17/34 underwent thrombolytic therapy without consideration of age if they had no contraindication for such treatment. Fifty-three patients were < or = 70 years old (mean age +/- SD 54 +/- 15 years; range 18 to 70), and 36 patients were > or = 71 years old (78 +/- 5 years; range 71 to 88). Except for mean age, there were no significant differences between the two treatment groups, particularly in terms of clinical presentation, average Miller score and pulmonary artery pressure regimen. Thrombolytic therapy was administered in the form of streptokinase at a dose of 100,000 IU/h over 12 h, with an initial injection of 250,000 IU over 15 min. Heparin was introduced 12 h after initiation of thrombolytic therapy. Urokinase or tissue-type plasminogen activator was used only in case of contraindication to streptokinase. RESULTS: The frequency of uncomplicated clinical course was the same in both treatment groups. Surgical embolectomy was necessary in three nonelderly patients (5.6%) and one elderly patient (2.7%). Changes in pulmonary pressure regimen and Miller score were identical in both groups. Three patients died during the in-hospital course: two nonelderly patients (3.7%) and one elderly patient (2.7%). Minor bleeding occurred in five nonelderly (9.4%) and five elderly (13.8%) patients (p = 0.74). Major bleeding was observed in three nonelderly (5.6%) and five elderly (13.8%) patients (p = 0.29). Bleeding subsequent to early invasive procedure accounted for six (75%) of eight patients with major bleeding: two nonelderly patients (one of whom died) and four elderly patients. No intracranial hemorrhage was observed. No predisposing factor for bleeding was identified, except the need for early vascular access for pulmonary angiography through the femoral approach or for percutaneous insertion of an intracaval device for partial interruption of the inferior vena cava. CONCLUSIONS: Thrombolytic therapy administered for massive pulmonary embolism in patients free of contraindication yields similar results and carries a similar risk for bleeding complications in elderly compared with nonelderly patients. Limiting early invasive procedures may result in less frequent major bleeding complications.

[Study of new thrombolytic agents in myocardial infarction: a multicenter randomized trial (APSAC versus rt-PA)]. / Etude des nouveaux thrombolytiques dans l'infarctus du myocarde (ENTIM): essai multicentrique randomisé (APSAC versus rt-PA).

A hundred and eighty three patients with a primary myocardial infarction less than 4 hours old were included in a double blind trial versus placebo comparing an isolated plasminogen streptokinase activator complex (APSAC: 30 mu in 5 mn) and tissue type plasminogen activator (rt PA: 10 mg bolus followed by 90 mg in 130 mn). Clinical evolution, side effects, patency of the artery responsible for infarction, left ventricular contractile function (contrast angiography on the 7th day and angioscintigraphy on the 21st day) and infarct size were studied. The two groups were comparable in age (54 +/- 11 years), delay in randomisation (170 +/- 50 mn), infarct site and severity of cardiac failure. There was no significant difference in hospital mortality (7 in the rt PA group and 5 in the APSAC group) or in adverse effects (haemorrhage: rt PA: 9 patients, APSAC: 11 patients). The patency was 72% in the APSAC and 76% in the rt PA group. Left ventricular function and infarct size were comparable in the two groups: angiographic EF (0.50 +/- 0.1 in the APSAC and 0.52 +/- 0.1 in the rt PA group: NS); asynergic score (11.3 +/- 1.7 in the APSAC and 10.5 +/- 1.8 in the rt PA group: NS); infarct size (10.9 +/- 8.0 in the APSAC and 9.4 +/- 7.2 in the rt PA group: NS). This trial shows that these two thrombolytic agents have the same efficacy. The authors recommend adaptation of the dosage of rt PA to body weight.

Long-term results of percutaneous aortic valvuloplasty compared with aortic valve replacement in patients more than 75 years old.

OBJECTIVES AND BACKGROUND: To assess the long-term results of percutaneous aortic valvuloplasty and aortic valve replacement in elderly persons, two similar nonrandomized series of patients greater than or equal to 75 years old treated by one or the other method between January 1986 and March 1989 in the same institution were compared. METHODS: Forty-six patients, 23 men and 23 women, with a mean age of 79.7 +/- 3.6 years (range 75 to 90) underwent percutaneous aortic valvuloplasty with use of the Cribier method (group 1). Twenty-three additional patients, 14 men and 9 women with a mean age of 78.4 +/- 2.4 years (range 75 to 86) underwent aortic valve replacement with a bioprosthesis (group 2). All of them suffered from severe calcified aortic stenosis. Clinical and hemodynamic status were similar in both groups. The mean follow-up period was 21.5 months (5 days to 60 months) in group 1 and 27.5 months (7 days to 61 months) in group 2. RESULTS: Three patients (6.5%) in group 1 died within 5 days after percutaneous aortic valvuloplasty; 24 patients (52%) died during the follow-up period, 16 of whom died of recurrent cardiac failure. Of 16 patients (35%) subsequently operated on at an average of 15.8 months after percutaneous aortic valvuloplasty, 2 died at operation. Only three group 1 patients (6.5%) are still alive without subsequent aortic valve replacement. In group 2, two patients (8.7%) died postoperatively and three (13%) died during the follow-up period. All other patients (78%) are still alive and in New York Heart Association functional class I or II. The overall survival rate in group 1 was 75% at 1 year, 47% at 2 years and 33% at 5 years. In group 2, the survival rate was 83% at 1 and 2 years and 75% at 3 and 4 years. CONCLUSIONS: The results of percutaneous aortic valvuloplasty do not compare favorably with those of surgery in elderly people, and this treatment should not be recommended.

[Arterial permeability, objective of thrombolytic therapy]. / La perméabilité artérielle, objectif du traitement thrombolytique.

The effects of thrombolytic therapy in acute myocardial infarction are related exclusively to coronary arterial reperfusion. This is the main factor which influences myocardial salvage, the conservation of left ventricular function and, ultimately, the reduction in mortality. From the beginning of the 80s, the patency (or reperfusion) rate was arbitrarily assesses at 90 minutes. However, arterial reperfusion is a progressive phenomenon and the patency rate in a population of acute myocardial infarctions varies with time. Depending on the thrombolytic agent and the rate of administration, the patency increases at a variable rate attaining a plateau at the 4th-6th hour, the maximal patency being obtained between the 24th to the 48th hour. Therefore, assessing patency at the 90th minute of thrombolytic therapy is an approximate and relatively inaccurate method of assessing the efficacy of a given thrombolytic agent. When evaluating a thrombolytic drug administered at a certain dosage, the rate of reperfusion and the value and precocity of the plateau phase must be taken into account. The respective performances of different thrombolytics in terms of arterial patency are comparable. Nevertheless, the rate of reperfusion with Streptokinase given at the dose of 1.5 million i.v. in 60 minutes is lower than that obtained with more recent thrombolytic drugs. Streptokinase also appears to be less active on chronic thrombi. The late patency rate after the 24th hour is over 90% with nearly all thrombolytic drugs but it would seem to be less with rt-PA because of a higher reocclusion rate associated with this particular agent. The study of reocclusion requires control coronary angiography between the 24th and 72nd hour (7th day in some studies). The prevalence of this complication is influenced by several factors, especially the severity of residual stenosis after thrombolysis and the grade of perfusion obtained after the treatment: secondary reocclusion is significantly lower with long-acting and non-fibrin specific thrombolytic agents. It is approximately 2 to 5% with APSAC, Streptokinase and pro-urokinase, and two to three times greater with rt-PA. Finally, the use of more powerful antiplatelet drugs than those currently available and of specific anti-thrombin agents could reduce the rate of secondary reocclusion. Associations of thrombolytic agents, the development of thrombolytic chimera and new thrombolytic molecules could improve the efficacy of thrombolytic therapy in terms of capacity of reperfusion and tolerance, especially with respect to haemorrhagic complications.

[Left ventricular remodeling after myocardial infarction]. / Le remodelage ventriculaire gauche après infarctus myocardique.

Left ventricular remodeling describes a number of geometric and structural changes that the left ventricle undergoes after myocardial infarction. Briefly, it comprises expansion of the infarct and dilatation of the healthy left ventricular segments. Its severity is related to the infarct size. These changes in ventricular geometry, in particular the dilatation, influence the long-term incidence of cardiac failure, the main secondary complication of myocardial infarction. Up to now, therapeutic interventions have been oriented to reducing the infarct size with the aim of avoiding or delaying the occurrence of left ventricular dysfunction. Nowadays, it seems possible to influence the natural process of post-infarction. Left ventricular remodeling independently of efforts to reduce infarct size. There is evidence that this process may be limited pharmacologically with angiotensin converting enzyme inhibitors. In animal studies, these agents limit remodeling and improve survival after myocardial infarction, but for the moment, despite confirmed benefits on left ventricular modeling, it is not possible to extrapolate these results in terms of clinical mortality.

Use of left ventricular function as an end point of thrombolytic therapy.

In recent acute myocardial infarction, early reperfusion of the infarct-related artery by intracoronary or intravenous thrombolytic therapy induces a significant limitation of infarct size, provided reperfusion occurs within a time frame that myocardial salvage can still be expected. Limitation of infarct size reduces scar tissue formation, aneurysm formation, infarct zone expansion, left ventricular volume enlargement, and eventually results in higher left ventricular ejection fraction. Infarct size limitation and left ventricular function preservation occur with all thrombolytic agents currently in clinical use: streptokinase, alteplase and, more recently, anistreplase. When anistreplase is compared with conventional heparin therapy, a 31% reduction in infarct size is found (estimated from single photon emission computed tomography, or SPECT). This translates into a significant preservation of left ventricular ejection fraction as observed in anistreplase-treated patients compared with heparin-treated patients (0.53 +/- 0.13 vs 0.47 +/- 0.12, p less than 0.002). In comparative trials of 2 thrombolytic agents, anistreplase was demonstrated to be as efficient as alteplase on left ventricular ejection fraction preservation and infarct size limitation.

[Percutaneous mitral valvuloplasty by Inoue's technique. Apropos of an experience of 71 cases]. / La valvuloplastie mitrale percutanée selon la technique d'Inoue. A propos d'une expérience de 71 cas.

Seventy-one consecutive, unselected patients underwent percutaneous mitral valvuloplasty by Inoue's technique between February and November 1990. The mean age was 53 years (range 32 to 75 years). Fifteen of the 71 patients had previously undergone surgical mitral commissurotomy. Three patients had Björk aortic valve prostheses. The mitral valve surface area increased from 1.1 +/- 0.2 cm2 to 1.95 +/- 0.5 cm2 (p less than 0.01) and the mean transmitral pressure gradient fell from 12 +/- 3 mmHg to 5 +/- 2 mmHg (p less than 0.05). Grade 3+ mitral regurgitation was observed in 4 patients. There were no cases of cardiac perforation or tamponade. The only complications were related to the catheterisation and not to the technique valvuloplasty (one case of prolonged fever which regressed with antibiotic therapy, one case of arteriovenous fistula at the site of femoral artery puncture). The QP/QS ratio was 1.1 +/- 0.2 at the end of the procedure. A QP/QS ratio greater than 1.5 was observed in one patient. A left-to-right shunt was observed in 53% of cases in the immediate post-valvuloplasty period with Doppler color flow imaging. In all, 78% of patients had a satisfactory result (mitral surface area greater than 1.5 cm2 and mitral regurgitation less than or equal to 2/4). These results are identical to those observed with the double balloon technique with a lower rate of complications. The duration of the procedure (104 +/- 13 min p less than 0.02) and of radioscopy (16 +/- 8 min, p less than 0.02) were shorter than with the double balloon technique.(ABSTRACT TRUNCATED AT 250 WORDS)

[Physiopathology of left ventricular remodeling after myocardial infarction]. / Physiopathologie du remodelage ventriculaire gauche après infarctus du myocarde.

The geometry of both the infarcted and non-infarcted zone of the left ventricle changes after myocardial infarction. Two mechanisms are involved: expansion of the infarcted zone and secondary dilatation of the non-infarcted zone. The necrosed area undergoes an inflammatory reaction followed by fibrosis which end up as a sca within a period of a few days to a few weeks. During this period if fibrous scarring the infarcted, thinned myocardium undergoes progressive expansion which starts in the first hours of the myocardial infarction. The loss of left ventricular systolic function related to the infarct and volumic overload created by expansion of the infarct influence the secondary development of dilatation of the non-infarcted zones. This dilatation results in restoration of left ventricular stroke volume but at the price of increased wall stress, which itself induces compensatory wall hypertrophy. These phenomena are more pronounced when the initial infarction is extensive and if they are sustained, they result in definitive myocardial failure. Several factors influence remodeling: the size of the infarct, arterial patency, wall stress and the quality of the scarring process itself. Therapeutic interventions of each of these factors can influence the remodeling. Limitation of infarct size by thrombolytic therapy, arterial revascularisation, even when performed late, seem capable of limiting expansion of the necrosed zone. Pharmacodynamic intervention of left ventricular afterload also affects ventricular remodeling. Nitrate derivatives, vasodilator therapy in general and converting enzyme inhibitors have been shown to be effective.

The double-balloon and Inoue techniques in percutaneous mitral valvuloplasty: comparative results in a series of 232 cases.

Immediate hemodynamic results of percutaneous mitral valvuloplasty were compared in two consecutive series of unselected patients from the same institution undergoing valvuloplasty with the double-balloon (161 patients) or the Inoue balloon (71 patients) technique. Before valvuloplasty, the patient series were comparable with regard to average age, gender repartition and most clinical, electrocardiographic, X-ray and hemodynamic variables. Poor anatomic forms of mitral stenosis were equally distributed in both series (41% vs. 45%, p = NS). The magnitude of mitral valve area increase and of mean mitral gradient decrease during percutaneous mitral valvuloplasty did not differ significantly in the Inoue balloon and double-balloon series (mean +/- SEM 1.1 +/- 0.2 to 1.95 +/- 0.5 and 1.0 +/- 0.2 to 1.97 +/- 0.5 cm2, respectively, for mitral valve area and 12 +/- 3 to 5 +/- 2 and 13 +/- 4 to 5 +/- 2 mm Hg, respectively, for mean mitral gradient). Four cases of 3+ mitral regurgitation occurred in the Inoue balloon series and 7 in the double-balloon series (p = NS). A good immediate result--defined as mitral valve area greater than or equal to 1.5 cm2 with greater than or equal to 25% in mitral valve area gain and mitral regurgitation less than 2+ at the end of the procedure--was observed in 78% of patients in both series. Three cases of tamponade due to chamber perforation and 14 cases of transient air embolism in the right coronary system due to balloon rupture were observed in the double-balloon series.(ABSTRACT TRUNCATED AT 250 WORDS)