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The guidelines of the European Society of Cardiology, published in 2003, consider primary angioplasty as the preferred treatment strategy in acute coronary syndromes with ST-segment elevation, if the procedure can be performed within 90 min after first medical contact. We report the experience of three Alsacian centers running a common prospective registry with 2504 consecutive patients enroled between January 1999 and December 2004. The average age of the patients was 62 years with a proportion of 24% women. The time delay "pain to admission" was > or =3 hours in 55.9% of the cases. The treatment delay "door to catheterisation needle" was 59 min and the mean delay "door-to-reperfusion" was 79 min. The study population was representative of the real world including subsets of patients with a particulary high risk profile: age > or =70 years in 33%, a Killip grade > or =3 in 11.5%, rescucitated sudden death in 6.6% and cardiogenic shock in 10.9% of the patients respectively. The immediate procedural success rate (Timi 3 flow) in the treated coronary artery was 96.5%. The overall inhospital mortality-rate was 9.3%. The combinations of rescucitated sudden death--cardiogenic shock or age > or =75 years--cardiogenic shock were associated with a poor clinical outcome and mortality rates of 69% and 72.6% respectively, where as in the absence of abovementioned clinical high risk settings, the mortality rate was as low as 1.4%. The overall bleeding complication rate was 1.4%. The policy of systematic primary angioplasty in acute coronary syndromes with ST-Segment elevation appears to be coherent. The procedural complications and the in-hospital mortality rates were low, except in the presence of above mentioned clinical high risk settings.

The object of this study was to assess the incidence and significance of atrioventricular block (AVB) induced by radiofrequency ablation of intranodal reentrant tachycardias. The study population was 18 patients aged 44 to 83, selected from a total population of 144 patients treated for recurrent, refractory tachycardias. These patients developed complete AVB (9 cases), 2nd degree ABV (3 cases) and 1st degree AVB (6 cases) either immediately or in the chronic phase after radiofrequency ablation. The outcomes were as follows: 1. In the 9 patients with complete AVB, the block regressed in a period ranging from 7 seconds to 5 minutes. It recurred as complete AVB 1 to 4 days later in 2 patients, and regressed again after a maximum of 10 days. One 47 year old woman had definitive complete AVB; 2. In the 3 patients with 2nd degree AVB, the block regressed within 7 days; 3. In the 6 cases of 1st degree AVB, 2 patients developed transient complete AVB the following day. The possible causes of AVB were: increased vagal tone in 1 case, ablation of the rapid pathway located in a postero-septal site in 8 cases and, in the remainder, pre-existing conduction defects. The authors conclude that transient complete AVB is common and usually has a good prognosis. Definitive complete AVB is a rare but possible (0.7%) complication of radiofrequency ablation of reentrant intranodal tachycardias; other forms of AVB generally regress quickly and, although they may recur within days, they carry a good prognosis in the following months. However, long-term follow-up remains necessary.

Curative radiofrequency ablation of the reentry circuit of paroxysmal junctional tachycardia is a relatively common method of treating this condition. The aim of this study was to determine whether the age of the patients should be taken into account for assessing the indication. The study population was 178 patients aged 18 to 86 years (average 56 +/- 19 years), who had paroxysmal junctional tachycardia and normal interatrial ECGs. One hundred and thirty-five patients were under 70 years of age (Group I) and 43 were over 70 (Group II). No significant differences in the mechanism of reentry, which was intranodal in 67% of cases, in the risk of immediate complications (11%) or in recurrence of tachycardia were observed between the two groups. Functional improvement was more spectacular in Group II with regression of the symptoms of associated cardiac disease and, above all, in reduction in the number of hospital admissions. The common association of cardiac disease and other pathologies in Group II should however lead to more careful management and follow-up of the more elderly patients. The authors conclude that radiofrequency ablation of paroxysmal junctional tachycardia in the over 70s is feasible and often provides better clinical results than observed in younger patients.

The aims of myocardial revascularisation are to treat angina, reduce ischaemia and improve life expectancy. Patients with multivessel disease have a poor prognosis, especially when the lesions are proximal, when the preseptal left anterior descending artery is involved and when left ventricular dysfunction is present. In this particular group of patients, coronary bypass surgery has been shown to improve 10 year survival. Coronary angioplasty has been compared with surgical treatment in many clinical trials. The medium-term survival is the same in both groups, but with a higher number of repeat procedures except in diabetic patients in whom mortality is higher after angioplasty. The use of coronary stents should reduce the number of post-angioplasty procedures. Constant technical improvements, the introduction of surgery without cardiopulmonary bypass, combined revascularisation procedures, new antiplatelet drugs, the absence of long-term comparative results, all this results in a personalized choice of revascularisation procedure based on the overall clinical and angiography features of each particular case.

The clinical significance of rapid monomorphic ventricular tachycardia (VT) (> 270 beats/min), also called ventricular flutter, remains controversial in patients without documented spontaneous sustained VT. The aim of this study was to evaluate the outcome of 115 patients with ischaemic heart disease, aged 58 +/- 10 years, without spontaneous ventricular arrhythmias, but who had inducible ventricular flutter during programmed ventricular stimulation. The patients underwent stimulation to evaluate the prognosis after myocardial infarction or to investigate a malaise with or without loss of consciousness. Sustained ventricular flutter was the only inducible arrhythmia in all patients. The mean left ventricular ejection fraction (LVEF) was 42 +/- 14%. During an average follow-up period of 66 +/- 43 months, 31 deaths, including 27 of cardiac causes, were observed. The 1, 5, and 11 year survival of the whole population was 94, 79 and 64% respectively. In univariate analysis, anterior wall myocardial infarction, a low LVEF, the presence of non-sustained ventricular tachycardia (NSVT) on 24 hour Holter monitoring and Class III antiarrhythmic treatment, were poor prognostic factors (p 0.05). In multivariate analysis, the only independent predictive factors of mortality were low LVEF (p = 0.006), the presence of NSVT on Holter monitoring (p = 0.003) and the absence of betablocker therapy (p = 0.015). Medical therapy with betablockers or the implantation of an automatic defibrillator may be indicated in these patients at higher risk.

The aim of this study was to determine whether advances in angioplasty techniques have improved results in multiple vessel coronary disease and to compare present results with those reported in randomised trials comparing angioplasty and surgery. The hospital results of two cohorts of multivessel coronary patients treated by angioplasty during two different periods were compared (group 1: 1990-1991. group 2: 1994-1995). The first period corresponded to the inclusion period of randomised trials comparing surgery and angioplasty. The patients in group 2 (n = 449) were older than those in group 1 (n = 424), had more triple vessel disease, more severe angina and more previous angioplasty attempts. Moreover, there were more cases of unfavourable lesions. Nevertheless, the clinical success rate was high in group 2 (92% vs 84%; p < 0.001) and the major complication rate (death, myocardial infarction or emergency bypass surgery) was lower (2.9% vs 6.1%; p = 0.02). The main technical difference between the two periods concerned the use of coronary stents (12% vs 8%; p < 0.001). The fact of being in group 2 was identified by multivariate analysis as an independent predictor for clinical success and a lower major complication rate. The authors conclude that, since the publication of randomised trials comparing angioplasty with coronary surgery, the hospital results of angioplasty have significantly improved. This should be taken into account in considering the clinical applications of the results of these trials.

A review of the results of randomised trials of the use of betablockers in acute myocardial infarction shows by techniques of meta-analysis that their prescription in the early hours of the acute event leads to a reduction in short-term mortality: the reduction of risk is 12% as compared with groups which are not given betablockers. In addition to its impact on mortality, early betablocker therapy is associated with a reduction in the risk of recurrence of myocardial infarction and a proven antalgic effect. However, in patients receiving thrombolysis, the beneficial effect on mortality and recurrence of infarction of intravenous betablockers seems less evident. In daily clinical practice, the prescription of betablockers in the first days of infarction has significantly increased over the last ten years. In the USIK trial carried out in France in November 1995, nearly two thirds of patients received betablocker therapy. In the same study, the prescription of betablockers is associated with a reduction in mortality independent of the classical risk factors and the prescription of angiotensin converting enzyme inhibitors. These results confirm the value of this therapeutic class in the acute phase of myocardial infarction.

The reproducibility of programmed ventricular stimulation has been previously demonstrated for periods of a few hours to several months. It has not been studied over longer intervals. The aim of this study was to assess the reproducibility of the method at long-term (> 2 years). Forty-six patients with underlying cardiac disease underwent two programmed ventricular stimulations in the absence of antiarrhythmic treatment at intervals of 2 to 6 years (mean 4 years). None of the patients had myocardial infarction or cardiac surgery during this period. The protocol was identical: up to 3 extra-stimuli were delivered in the two right ventricular sites over 3 cycles. Twenty-eight patients had inducible sustained monomorphic ventricular tachycardia during the first investigation (Group I): the investigation was negative in the remaining 18 patients (Group II). During the second investigation, 26 of the 28 patients in Group I had inducible ventricular tachycardia, the rate of which decreased from 206 +/- 50 bpm to 196 +/- 54 bpm. The induced ventricular tachycardia was slower in 15 patients and faster in 5 patients. The mode of induction was different in 12 cases. In Group II, 4 patients (22%) had inducible sustained ventricular tachycardia at the second investigation. The authors conclude that the reproducibility of programmed ventricular stimulation remains good in the long-term in subjects within inducible tachycardia, demonstrating the stability of the arrhythmogenic substrate; the frequency of this tachycardia is generally slower. In subjects with an abnormal initial investigation who became symptomatic, it may be useful to repeat programmed ventricular stimulation.

Evaluation of heart rate variability is a common method of assessing autonomic nervous system function and its effects on heart rate in different conditions. The reproducibility of the technique is not known in the chronic phase of myocardial infarction. The aim of this study was therefore to assess the reproducibility of the measurement in 54 subjects who were clinically stable with no change in treatment at a distance from acute or semi-recent (> 2 years) myocardial infarction, after an interval of one month. The temporal and spectral analysis of heart rate variability included measurement of the standard deviation of the normal RR intervals (SDNN), on the mean heart rate, the percentage of RR intervals greater than 50 ms than the adjacent interval (pNN50), the coefficient of variability (CV), the square root of the differences between successive RR intervals (rMSSD), the power of low frequencies (LF) and high frequencies (HF) and of the fractional spectral power (LF/HF). No significant changes in these parameters were observed. Analysis of individual variations showed that the heart rate was the most stable parameter: for evaluation of vagal tone, the rMSSD showed less variability than the pNN50 and HF. The presence of cardiac disease did not influence these results. The authors conclude that parameters of evaluation of heart rate variability in temporal and spectral analysis are globally reproducible in stable subjects. However, individual values may change from one measurement to another. Nevertheless, abnormal variability is constantly observed at the second investigation and, similarly, normal variability also remains unchanged. These individual variations suggest that, for the demonstration of change in these parameters of variability with treatment, large population groups must be studied.

The study of heart rate variability is a new means of assessing autonomic nervous system function and the risks of cardiac and sudden death in patients with advandec cardiac disease. The aim of this study was to analyse changes in heart rate variability in the hours preceding cardiac death and just before its occurrence. Seventeen subjects aged 78.5 +/- 10 years, with advanced cardiac disease responsible for a reduction of left ventricular ejection fraction below 40%, died during Holter ECG recording. Ten died of ventricular fibrillation, 5 of bradycardia and 2 of non-rhythmic causes. General analysis of heart rate variability showed a decrease in all but 1 patient, the average standard deviation of normal RR intervals in subjects in sinus rhythm being 53 +/- 14 msec and the fractioned spectral power (low frequency/high frequency power) being 1 +/- .07. The change in heart rate variability did not allow prediction of the mechanism of death: the mean heart rate only increased before death in 3 of the patients with an ischaemic component in the hours before death, the indices of vagal tone were very low in the majority of patients and, just before death, a disequilibrium between the spectral powers with a sudden increase in LF/HF ratio of 10 of the 17 patients, irrespective of the cause of death, appeared. In conclusion, a decrease in heart rate variability was observed in all cases but did not predict the mechanism of death. Just before death occurred, some patients, especially those with acute ischaemia, showed a sudden change in the indices of heart rate variability indicating a terminal vaso-sympathetic disequilibrium.

Programmed atrial stimulation is a technique increasingly used to assess different pathologies but the reproducibility of the results is totally unknown. The aim of this study was to determine its reproducibility. Two electrophysiological studies were undertaken without antiarrhythmic therapy in an interval of one to three months (average 18 months) in 48 patients. The programmed atrial stimulation used 1 and 2 extrastimuli delivered in sinus rhythm and then three paced rhythms (sinus cycle -10%, 600 ms, 400 ms). Twenty-one patients had documented atrial arrhythmias (atrial fibrillation n = 13, flutter n = 3 or tachycardia n = 5) (group 1) and the 27 other patients had no spontaneous arrhythmias (group II). In group I, clinical tachycardial was reproduced in 18 patients during the initial stimulation procedure. During the second investigation, 17 remained inducible and in the 3 in whom stimulation was negative, it remained so in 2 of the cases. The reproducibility was therefore 90%. In group II, 12 patients had inducible sustained (for over 1 minute) tachycardia during the first procedure (44%) but this only remained inducible in 6 patients. In the other 15 subjects, stimulation was negative during the first procedure but 7 of them had inducible tachycardial during the second procedure. The reproducibility of the technique was therefore only of 52%. The authors conclude that the reproducibility of programmed atrial stimulation in patients with documented spontaneous paroxysmal arrhythmias is excellent. However, the reproducibility is mediocre in subjects without spontaneous arrhythmias and the induction of tachycardial in this group of patients should be interpreted with caution given the variability of the response to programmed atrial stimulation.

1/1 atrial tachycardia or "quinidine" flutter under class I antiarrhythmic drugs is a serious complication of these agents which, unfortunately, cannot be anticipated. The aim of this study was to review the cases of 11 patients who had suffered this complication of class I antiarrhythmic therapy to see if it could have been prevented. All drugs of this class were included. The 11 subjects were aged 57 to 78: 7 had no apparent underlying cardiac disease and the others had valvular (n = 1), hypertensive (n = 1) and ischaemic (n = 2) heart disease. They were treated for episodes of paroxysmal atrial fibrillation or tachycardia. In the absence of treatment, 7 patients had a short PR interval on the ECG (PR between 0.11 and 0.14 s). In the other 4, the PR interval was normal (0.16 to 0.20 s), but the P wave was widened with appearances of left atrial hypertrophy or an intra-atrial conduction defect. High amplification ECG performed in 3 patients showed continuity of atrial and ventricular depolarisation. Atrial stimulation showed excellent nodal conduction with a Wenckebach point of 200/min. The authors conclude that a short PR interval is predisposing factor to 1/1 atrial tachycardia with class I antiarrhythmics. High amplification ECG which allows identification of the end of the P wave with respect to the QRS complex could help identify subjects at risk when the P wave is widened and that, consequently, the PR interval appears to be normal.

The authors report the case of a 56 year old patient in whom the mechanisms of a wide QRS complex tachycardia recorded on an intensive care monitor could not be determined. The patient also had episodes of atrial flutter with left bundle branch block. Programmed ventricular stimulation with 3 extrastimuli triggered a non-specific ventricular flutter. One week later, the patient was resuscitated from a cardiac arrest which was undocumented. It was therefore important to elucidate the mechanism of the initial tachycardia. A second session of programmed ventricular stimulation was undertaken. As the use of 2 extrastimuli triggered runs of unsustained polymorphic ventricular tachycardia, the classical protocol was stopped. An infusion of low-dose isoproterenol was used to repeat programmed stimulation with a single extrastimulus. This protocol triggered sustained monomorphic ventricular tachycardia at 240/min. The diagnosis of ventricular tachycardia could therefore be continued.

Radiofrequency ablation of the slow pathway of the reentry circuit is the usual radical treatment of nodal tachycardia. It is, however, possible to create atrioventricular conduction defects, the significance of which is not known. The aim on this study was to report the history of these conduction defects created during ablation of the slow pathway of the intranodal reentry circuit. Four cases were observed in a series of 27 patients. In one female patient, complete atrioventricular block was observed for 5 minutes before conduction returned to normal followed by recurrence of the tachycardias. Three other women developed complete atrioventricular block one to four days after the ablation. The block regressed after a maximum delay of 7 days. Six months to one year after the procedure, these three patients remain free of tachycardia and have only first degree atrioventricular block on the surface ECG. These patients were not implanted with a pacemaker. The authors conclude that complete atrioventricular block after ablation of the slow pathway may be treated conservatively, providing it is well tolerated. It normally regresses within few days.

The aim of this study was to evaluate the results of signal-averaged (SA) ECG in cases of complete right (RBBB) or left bundle branch block (LBBB). One hundred and seven patients had RBBB; 42 without cardiac disease (0), 56 with chronic myocardial infarction (MI) and 9 with primary cardiomyopathy (CMP). Seventy-four patients had LBBB: 20 without cardiac disease, 26 with chronic myocardial infarction and 28 with primary cardiomyopathy. A SA ECG (Cardionics, Fidelity) was performed with a 40 Hz band pass and compared with the recordings of 72 healthy controls without bundle branch block. The duration of the averaged QRS (QRS dur), the voltage of the last 40 milliseconds (RMS40) and duration of terminal activity < 40 microV (LAS) were measured. The analysis of results showed that QRS dur was significantly longer in subjects with ventricular tachycardia (VT) (p < 0.05) and in those with advanced cardiac disease (p < 0.05), whatever the type of bundle branch block, and that only the RMS40 distinguished patients with VT from those without VT, irrespective of the underlying cardiac disease and the type of bundle branch block. However, the study of the diagnostic value of each parameter showed very mediocre results: RMS 40 < 20 microV in myocardial infarction and < 17 microV in cardiomyopathy had sensitivities and specificities in RBBB of 73% and 50% respectively, incalculable in CMP, in LBBB 70% and 33%, 77% and 60% respectively; the LAS was unusable. The authors conclude that it is hazardous to interprete SA ECG in bundle branch block, especially in advanced cardiac disease where the specificity of the criteria becomes very low (< 50%).

Analysis of heart rate variability (HRV) by Holter monitoring is the method of choice for assessing the cardiac autonomic regulation. Rapid ventricular stimulation also provokes changes in the autonomic nervous system tone. The aim of this study was to compare time and frequency domain analysis of HRV (Elatec version 3.02) with variations of HR observed after incremental ventricular stimulation to 200/min in 130 patients. In 80 patients, ventricular stimulation provoked an initial acceleration in HR followed by a slowing with a variation of over 10%. In the other 50 patients, these variations were not observed. Holter analysis of HRV showed concordance between the two methods. In time domain analysis, the standard deviation of normal R-R intervals, the coefficient of variability [(CV = SD/mean RR) and percentage of adjacent RR intervals with a difference of more than 50 msec (pNN 50) were significantly reduced in the abnormal group, the respective values in the normal and abnormal groups being: SD 122 vs 72 msec; CV 15 versus 9% and pNN50 9 versus 5%)]. In frequency domain analysis, there was a reduction of low and high frequency spectra and of the ratio of low/high frequencies in abnormal subjects. The authors conclude that the disappearance of HR changes after ventricular stimulation is correlated to the absence of HRV on Holter recording. This simple test may be performed systematically during electrophysiological investigations. The measurements are reproductible and the results are not affected by arrhythmias or technical problems of quality recording by the Holter method which may affect analysis of HRV.

The aim of this study was to determine the influence of the chronicity of myocardial infarction on QRS duration. The signal-averaged electrocardiogram (SA ECG) was recorded with a 40 Hz filter in 239 patients with a history of myocardial infarction. The infarction was recent (up to 6 weeks) in 105 patients (group A) and chronic (> 1 year) in the other 134 cases (group B). In group A, 35 patients had inductible sustained ventricular tachycardia (VT) at less than 270/mn; 40 had negative electrophysiological investigations and 30 had inducible ventricular flutter or fibrillation (VF). In group B, 58 had inducible VT, 54 had negative investigations and 22 had inducible VF. The three SA ECG parameters (QRS duration, amplitude of RMS 40 and duration of LAS) differed significantly in subjects with VT with respect to those with negative investigations and inducible VF, irrespective of the chronicity of infarction. On the other hand, only QRS duration differentiated patients with recent infarction from those with chronic infarction, irrespective of the results of programmed pacing, QRS duration being longer in group B. The best diagnostic value of QRS duration for identifying subjects with VT < 270/mn and negative investigations was 110 ms in group A and 120 ms in group B (sensitivity 46% and 77.5% respectively). In chronic infarction, the increase in QRS duration was significantly correlated to the decrease in left ventricular ejection fraction. The authors conclude that the criteria of abnormality of QRS duration are dependent on the chronicity of myocardial infarction. Although a duration of 110 ms is abnormal in the early post-infarction period, after a period of one year, a value of 120 ms should be considered to be pathological, especially when the sequellae of infarction are important.