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Introduction: The aim of this study was to determine whether impaired adaptation of the QT interval to changes in heart rate predicts sudden death after an acute myocardial infarction. Methods and Results: The Groupe d'Etude du Pronostic de l'Infarctus du Myocarde (GREPI) trial was a prospective multicenter study designed to evaluate the long-term outcome of myocardial infarction. QT dynamicity was evaluated in 265 patients by analyzing 24-hour Holter recordings obtained 9 to 14 days after myocardial infarction. The linear regression slope of QT intervals measured to the apex and to the end of the T wave (QTe) plotted against RR intervals was calculated using a dedicated Holter algorithm. The value of QT/RR in predicting sudden death and total mortality was compared with those of ejection fraction, heart rate variability, and late potentials. Mean follow-up was 81 ± 27 months. There were 73 deaths, of which 23 were sudden. Of all the parameters, an increased diurnal QTe/RR slope (>0.18) was the strongest independent predictor of sudden death (relative risk 6.07, confidence interval 1.48–24.95,P = 0.01). Conclusion: Increased diurnal QTe dynamicity is independently predictive of sudden death among patients with myocardial infarction. This simple parameter may help to stratify risk and select patients who may benefit from antiarrhythmic prophylaxis.(J Cardiovasc Electrophysiol, Vol. 14, pp. 227-233, March 2003)

ObjectivesThis meta-analysis compared amiodarone with placebo and class Ic drugs for the cardioversion of recent-onset atrial fibrillation (AF), defined as lasting less than seven days.BackgroundDespite the lack of trials that support its efficacy convincingly, amiodarone is widely used for conversion of recent-onset AF.MethodsWe searched Medline and EMBASE databases, as well as the Cochrane Controlled Trials Register for randomized trials on recent-onset AF comparing amiodarone to placebo or class Ic drugs. Data were combined according to a fixed effect model. The primary end point was the rate of conversion at 24 h. To study time-dependency of the drugs, efficacy at 1 to 2 h, 3 to 5 h, 6 to 8 h, and at 24 h was analyzed.ResultsWe found six studies randomizing amiodarone versus placebo (595 patients) and seven studies versus class Ic drugs (579 patients). There was no significant difference between amiodarone and placebo at 1 to 2 h, but significant efficacy was found after 6 to 8 h (relative risk [RR] 1.23, p = 0.022) and at 24 h (RR 1.44, p < 0.001). Efficacy with amiodarone was inferior to class Ic drugs for up to 8 h (RR 0.67, p < 0.001) but no difference was seen at 24 h (RR 0.95, p = 0.50). There were no major adverse effects.ConclusionsAmiodarone is superior to placebo for cardioversion of AF, and even though the onset of conversion is delayed, its efficacy is similar at 24 h compared with class Ic drugs. These results favor amiodarone as a reasonable alternative for patients with recent AF in whom class Ic and other, more rapidly acting antiarrhythmic drugs cannot be used.

Background: Although well-defined clinically and electrocardiographically, Acquired Long QT Syndrome (LQTS) remains elusive from a pathophysiologic point of view. An increasingly accepted hypothesis is that it represents an attenuated form of Congenital Long QT Syndrome. To test this hypothesis further, we investigated patients with Acquired LQTS, using various investigations that are known to give information in patients with Congenital LQTS. Methods: All the investigations were performed in patients with a history of Acquired Long QT Syndrome, defined by marked transient QT lengthening (QT>600 ms) and/or torsades de pointes. Measurement of the QT interval dispersion, the interlead difference for the QT interval on a 12-lead ECG, was performed in 18 patients and compared with 18 controls, matched for age and sex. To assess sympathetic myocardial innervation, I-123 Meta-iodobenzylguanidine (I-123-MIBG) scintigraphy was performed in 12 patients, together with Thallium scintigraphy, to rule out abnormal myocardial perfusion. Time—frequency analysis of a high-resolution ECG using a wavelet technique, was made for nine patients and compared with 38 healthy controls. Finally, genetic studies were performed prospectively in 16 consecutive patients, to look for HERG , KCNE1 , KCNE2 and KCNQ1 mutations. The functional profile of a mutated HERG protein was performed using the patch-clamp technique. Results: Compared with the control group, a significant increase in QT dispersion was observed in the patients with a history of Acquired LQTS (55±15 vs. 33±9 ms, P

Aims Ablation of the atrial isthmus between the tricuspid annulus and the inferior vena cava changes P-wave morphology during low lateral right atrial pacing. For better understanding of the mechanism of this alteration, the sequence of activation of the inter-atrial septum and the left atrium were compared before and after ablation of the isthmus between the inferior vena cava and the tricuspid annulus. Methods and Results In 13 patients, left atrial mapping was performed using a duodecapolar electrode catheter advanced to the far distal coronary sinus. The inter-atrial septum was mapped using a right atrial duodecapolar electrode catheter. Conduction times were measured during low lateral right atrial pacing from the pacing artefact and during sinus rhythm from the earliest right atrial electrogram to every intra-cardiac electrogram before and after the ablation. During low lateral right atrial pacing, isthmus ablation resulted in a significant delay in every left atrial lead. Changes were maximal at the posterior aspect of the left atrium and minimal at its anterior aspect. No significant change was discernible on the inter-atrial septum. During sinus rhythm, atrial activations remained unchanged. Conclusion Electrocardiographic changes of P-wave morphology result from alteration in the sequence of left atrial activation rather than that of the inter-atrial septum.

Objective ST-segment elevation in acute pericarditis is believed to be caused by superficial myocardial inflammation or epicardial injury. We used cardiac troponin I, a sensitive and specific marker of myocardial injury, to assess myocardial lesions in idiopathic acute pericarditis and its relationship to ST-segment elevation. Patients and Methods Sixty-nine consecutive patients (53 men, 48±17 years) with idiopathic acute pericarditis were included. We used an enzymoimmunoflurometric method to measure serum cardiac troponin I on admission (myocardial infarction threshold was 1·5ng.ml−1). Results Cardiac troponin I was detectable in 34 patients (49%) and was beyond the 1·5ng.ml−1threshold in 15 (22%). Coronary angiography performed in seven of these 15 patients was normal in all of them. ST-segment elevation was observed in 93% of the patients with cardiac troponin I >1·5ng.ml−1vs 57% of those without ( P

Background Late potentials (LPs) in the terminal portion of the QRS complex are commonly sought to identify post-myocardial infarction patients prone to ventricular tachyarrthythmias (VT) or sudden death. More recent time–frequency signal processing tools have been shown to provide new parameters for the quantification of LPs and abnormal activities buried within the QRS complex. Methods and Results The study population comprised 23 myocardial infarction patients with documented sustained VT (MI+VT), 40 myocardial infarction patients without VT (MIVT) and 31 normal subjects. The reproducibility of the method was tested in an additional set of 66 patients. The signal-averaged high-resolution electrocardiograms (HRECGs) were quantified by deconstructing the unfiltered X, Y and Z leads using a 511-orthogonal wavelet network. Using receiver operating characteristics (ROC) curves and discriminant analysis applied to the wavelet coefficients, we extracted the most significant wavelets to classify the post MI patients. These wavelets detected time–frequency alterations both in the ST segment and within the QRS complex, characterizing patients prone to VTs. The same statistical methods were applied to the conventional time-domain measurements. The combined application in our population of the orthogonal wavelet deconstruction method and discriminant analysis had 91% sensitivity and 95% specificity, an improvement of 22% and 25%, respectively, compared with the conventional time–domain method. Reproducibility was 82%. Conclusions In post-myocardial infarction patients, orthogonal wavelet transforms can detect alterations in high-frequency components within the QRS and ST segment. Our findings support the view that waveletrelated parameters are more relevant than those of the time–domain method in predicting subsequent malignant tachyarrhythmias. (Europace 2000; 2: 141–153)

Background —Infection remains a severe complication after pacemaker implantation. The purpose of our prospective study was to evaluate the role of the local bacteriologic flora in its occurrence. Methods and Results —Specimens were collected at the site of implantation for culture from the skin and the pocket before and after insertion in a consecutive series of patients who underwent elective permanent pacemaker implantation. Microorganisms isolated both at the time of insertion and of any potentially infective complication were compared by using conventional speciation and ribotyping. There were 103 patients (67 men and 36 women) whose age ranged from 16 to 93 years (mean±SD, 67±15). At the time of pacemaker implantation, a total of 267 isolates were identified. The majority (85%) were staphylococci. During a mean follow-up of 16.5 months (range, 1 to 24), infection occurred in four patients (3.9%). In two of them, an isolate of Staphylococcus schleiferi was recognized by molecular method as identical to the one previously found in the pacemaker pocket. In one patient, Staphylococcus aureus , an organism that was absent at the time of pacemaker insertion, was isolated. In another patient, a Staphylococcus epidermidis was identified both at the time of pacemaker insertion and when erosion occurred; however, their antibiotic resistance profiles were different. Conclusions —This study strongly supports the hypothesis that pacemaker-related infections are mainly due to local contamination during implantation. S schleiferi appears to play an underestimated role in infectious colonization of implanted biomaterials and should be regarded as an important opportunistic pathogen.

Objectives. Our aim was to look at the clinical features and long-term follow-up of seven patients without coronary artery disease, who had a history of life-threatening ventricular arrhythmias due to coronary spasm. Background. Arrhythmic cardiac arrest due to isolated coronary spasm is rare, and there is limited information on the patients affected by this entity alone. Methods. The seven patients were recruited retrospectively from a cohort of survivors of cardiac arrest. None had a history of angina pectoris, structural heart disease or significantly narrowed coronary segments. All had a positive ergonovine provocation test result. Results. The patients’ mean age was 44 years; three were male and four female. All were habitual cigarette smokers. No arrhythmias were induced on programmed ventricular stimulation; corrected QT interval (QTc) and corrected JT interval (JTc) dispersion were within normal ranges. After the ergonovine provocation test, treatment with calcium channel blocking agents (diltiazem, verapamil, nifedipine or amlodipine) was initiated at a dose determined by titration until a negative test result was obtained. At a mean follow-up interval of 58 months for the total group, six patients remained free of symptoms, whereas the one patient who did not stop smoking had a new cardiac arrest despite treatment for coronary spasm. Conclusions. A favorable long-term outcome may be expected in survivors of cardiac arrest due to coronary spasm, in the absence of significant coronary artery disease. Calcium channel blockers are the most appropriate therapy in these patients. These observations provide further evidence for the role of silent ischemia in cardiovascular death.

Wavelet analysis provides a fruitful alternative to standard techniques for the detection of fractionated potentials in signal averaged high-resolution (SA-HR) ECGs. In this study, an attempt is made to optimize the discrimination of post infarction patients prone to ventricular tachycardia (VT), using wavelet analysis. Optimization is based on the choice of the ECG leads or lead combinations to be analyzed, and on the analyzing wavelet to be computed. A set of 40 post-infarction patients (20 patients with VT and 20 patients without any arrhythmia) is analyzed. Individual leads and lead combinations of the SA-HR ECGs are processed using a multiparametric algorithm, based on coherent detection of aligned local maxima of the wavelet transform. Seven basic wavelets are tested: the Morlet's wavelet, and the six first derivatives of a Gaussian function. The first derivative of a Gaussian function provides poor results, and is discarded. All other wavelets prove to perform equivalent classification. A vector magnitude computed from the wavelet transforms of the three SA-HR ECGs achieves better results than individual leads. An optimized risk stratification algorithm leads to 90% sensitivity and 100% specificity in the 40 patients learning set.

BACKGROUND Previous reports have shown that radiofrequency ablation can terminate atrial flutter and prevent recurrences. However, different methods have been used, and the current experience remains limited. The objective of the present study was to determine the efficacy of radiofrequency ablation of atrial tissue in patients with atrial flutter using an anatomically guided approach. METHODS AND RESULTS We treated 22 patients aged 30 to 73 years. Atrial flutter was recurrent for a mean of 5 years despite the administration of multiple antiarrhythmic drugs. Radiofrequency current was directed to the atrial isthmus between the inferior vena cava and the tricuspid ring, regardless of the morphology of local electrograms. Radiofrequency energy was applied during typical atrial flutter in 12 patients, atypical atrial flutter in 2 patients, and successively both forms in 8 patients. In 19 patients, atrial flutter abruptly terminated. In 3 patients, atrial flutter persisted despite 37, 48, and 25 applications, respectively. Atrial recordings demonstrated that atrial flutter termination occurred as a consequence of conduction block at the site of radiofrequency energy application, regardless of the type of atrial flutter. The number of applications before termination ranged from 1 to 82 (mean, 32). Atrial flutter could no longer be induced in every case. There were no complications. During a 13-month mean follow-up, atrial flutter recurred in only 2 of the 19 patients who had a successful ablation. Four patients experienced chronic atrial fibrillation, and 2 of them returned to sinus rhythm with antiarrhythmic therapy. CONCLUSIONS Radiofrequency ablation of atrial flutter using anatomic guidance is feasible and effective. Further experience is needed to delineate its role as an alternative approach to the management of refractory atrial flutter.

International audience; The authors present an original method for the discrimination of patients prone to ventricular tachycardia. The wavelet transform, which is a new time-scale technique suitable for transient signal detection, was applied to bipolar unfiltered X, Y, Z signal-averaged electrocardiograms in 20 postinfarction patients with sustained ventricular tachycardia, in 20 myocardial infarction patients without ventricular tachycardia, and in 10 healthy subjects. An improved automated algorithm for the detection and localization of sharp variations of the signal, based on coherent detection of the local maxima of the wavelet transform, was developed. A risk stratification method, based on the detection of at least one singularity at or after a point defined with reference to the QRS onset, was assessed. The optimum cutoff point, found 98 ms after the onset of QRS, provides a specificity of 90% and a sensitivity of 85%. The authors conclude that wavelet analysis makes it possible, in this group of patients, to discriminate those with ventricular tachycardia. It yields better results than those obtained from the conventional time-domain approach.

International audience; BACKGROUND: Randomized studies evaluating left atrial radiofrequency ablation (RFA) in patients with persistent atrial fibrillation undergoing mitral valve surgery are scarce and monocentric. AIM: To evaluate the efficacy of left atrial RFA concomitant with mitral valve surgery to restore and maintain sinus rhythm. METHODS: The SAFIR is a multicentre, double-blinded, centrally randomized study involving four university hospitals. Between December 2002 and September 2005, 43 patients with mitral valve disease and long-standing, persistent atrial fibrillation (duration>6 months) were included. We compared valvular surgery alone (n=22) or with left atrial RFA (n=21). The main endpoint was sinus rhythm at 12 months without recurrence of arrhythmia during follow-up. Secondary endpoints were surgical adverse events, atrial fibrillation relapses, stroke and echocardiographic measurements after three and 12 months' follow-up. Analyses of the efficacy criteria were performed on an intention-to-treat basis. RESULTS: The primary endpoint occurred significantly more often in the RFA group than in the control group (respectively, 12/21 patients [57%] vs 1/22 patients [4%]; p=0.004). There were more patients with sinus rhythm in the RFA group than in the control group at discharge (72.7% vs 4.8%; p

Eleven male patients, New York Heart Association (NYHA) Class III, have undergone cardiomyoplasty (Chachques and Carpentier technique). There were no deaths. Two patients suffered from low cardiac output, one patient suffered a massive aortic bifurcation embolism, and one patient had a Legionella pneumonia. All patients recovered well. The follow-up was 6.9 +/- 2.3 months. One patient had a Cardiomyostimulator Pulse Train Generator failure and had it replaced. The first seven patients were evaluated 6 months after surgery. They all improved (Class II) except for one, who was transplanted. The maximal level of exercise was improved (92 +/- 18 W vs 60 +/- 24 W), as was the heart rate-systolic blood pressure product (30,262 +/- 3,119 vs 19,908 +/- 4,190), mainly due to an increase in systolic blood pressure (200.0 +/- 25.5 vs 141.5 +/- 20.3 mmHg). Echographic parameters, maximal oxygen consumption, left ventricular ejection fraction (LVEF), cardiac index, oxygen arteriovenous difference, and cardiac filling pressures did not change. The left ventricular (LV) angiography always showed good contraction of the latissimus dorsi. A problem needing investigation is the principle of cardiomyoplasty (CMP) itself, as the muscle acts more as a lift than as pincers. Our patients, and patients from other series, improved functionally, and they exercised more. Improvement in survival can be studied only by a randomized clinical trial.

This study evaluated the prevalence of increased cardiac troponin I (cTnI) in patients with acute aortic dissection of the ascending aorta (type A).In 119 consecutive patients with type A acute aortic dissection, serum cardiac troponin I was measured along with clinical, haemodynamic, electrocardiographic and echocardiographic variables obtained on admission. Cardiac troponin I was positive in 28 patients (23.5%; mean +/- SD: 6.1 +/- 14.7 ng/ml) and above the myocardial infarction threshold (1.5 ng/ml) in 12 (10%). Catecholamine infusion (17.9% vs. 4.4%; p = 0.03) and higher value of creatinine (35.7% vs. 15.4%; p = 0.03) were more frequent in patients with elevated troponin. Total mortality was 29.7% (n = 35) and surgical mortality was 16.8% (n = 17). An increased troponin was discriminatory with respect to mortality (OR: 4.1 (1.6-9.9); p = 0.002) in univariate analysis. However, this association was lost when other markers of death (age, stroke, ST-segment elevation, tamponade, catecholamine infusion, renal failure) were added in a multivariate model (OR: 2.2 (0.7-7.4); p = 0.19) indicating that the myocardial loss associated with troponin increase is not in itself a factor of mortality.Cardiac troponin I elevation is frequent in patients with type A aortic dissection. It might reflect a higher haemodynamic stress but does not necessarily reflect a negative prognosis.

Introduction Studies evaluating changes in HRV preceding the onset of ventricular arrhythmias using conventional techniques have shown inconsistent results. Time-frequency analysis of HRV is traditionally performed using short-term Fourier transform (STFT). Wavelet transform (WT) may however be better suited for analyzing non-stationary signals such as heart rate recordings. Methods and results We studied patients with a history of myocardial infarction implanted with a defibrillator with an extended memory. The RR intervals during the 51 min preceding ventricular events requiring electrical therapy were retrieved, and HRV studied by WT and STFT. 111 episodes of ventricular arrhythmia were retrieved from 41 patients (38 males, age 64±8 years). Heart rate increased significantly before arrhythmia. There was no significant variation in low frequency / high frequency components (LF/HF) observed for the group as a whole, probably due to a great degree of heterogeneity amongst individuals. A subset of 30 patients also had heart rate recordings performed during normal ICD follow-up. WT did not show any difference in HRV before arrhythmia onset and during control conditions. Conclusion Variations in HRV before onset of ventricular arrhythmias were not apparent in this large dataset, despite use of optimal tools for studying time-frequency analysis.

Objective: To determine factors predictive of mortality in patients undergoing emergency mitral valve surgery in the setting of severe post-infarction regurgitation. Methods: Patients admitted for an acute myocardial infarction who required urgent mitral valve surgery for severe regurgitation were studied. Factors predictive of outcome were analysed. Results: Fifty-five consecutive patients (mean 65 ^ 10 years, 37 males) were included. The infarct was inferior in 31 patients, posterior in 10, anterior in 9 and lateral in 5. Thirty-four patients (62%) were in Killip class IV. Peroperative findings confirmed total papillary muscle rupture in 25 patients (posteromedial in 21, anterolateral in 4), and partial rupture in 12 patients (posteromedial in 10, anterolateral in 2). Papillary muscle dysfunction without rupture was responsible for regurgitation in 18 patients (posteromedial in 15, anterolateral in 3). The mitral valve was replaced by a prosthesis in all but 4 patients, who had valvuloplasty. Coronary angiography was done in 32 patients, of whom 18 underwent concomitant coronary artery bypass grafting and 2 balloon angioplasty. Surgery was performed on average 7 days after infarction. Thirteen patients (24%) died during the perioperative period. Absence of coronary revascularisation was significantly associated with increased perioperative mortality (34% vs. 9%, P ¼ 0:02Þ: Of the 42 surviving patients, there were 5 deaths during a mean follow-up of 4.0 ^ 3.7 years. Conclusion: In patients with acute post-infarction mitral regurgitation, perioperative mortality is high, but can be improved with concomitant CABG in addition to valve surgery. Long-term outcome of survivors is favourable. q 2004 Elsevier B.V. All rights reserved.

To describe the preoperative clinical, echocardiographic and biological findings in patients with acute aortic dissection and attempt to specify high risk factors of preoperative mortality.A retrospective, monocentric study of 148 patients admitted for acute type A aortic dissection. All patients underwent a clinical, echocardiographic and biological evaluation on admission. In 75 patients, we measured serum cardiac troponin I (cTnI).In hospital mortality was 25.9% and 15.6% presented with preoperative cardiac circulatory arrest (POCCA). Patients with POCCA were more likely than others to have hypotension (97+/-56 vs 144+/-24 mmHg, p0.01) or shock (52% vs 3%, p0.01) on admission. Pericardial effusion (65% vs 35%, p=0.01) and tamponade (61% vs 8%, p0.01) were also significantly linked to POCCA but not the aortic ascendant diameter. Detection of cTnI was more frequent in patients with POCCA (24% vs 7%, p=0.051) and was found to be a good predictor of in hospital mortality (47% vs 14%, p0.01).For patients with acute type A aortic dissection, hypotension or shock on admission, pericardial effusion or tamponade, as well as cTnI detection, were the main predictors for POCCA and imply immediate surgery.

The purpose of this study was to determine the incidence and significance of troponin i (tni) elevation in acute pericarditis.We retrospectively included 69 patients with acute idiopathic pericarditis. We analyzed ECG recordings, echocardiography findings and tni level. Thirty-four patients (49%) had detectable tni (0.5 ng/ml), 15 (22%) had a significantly elevated level (1.5 ng/ml). There was a significant correlation between elevated tni level and ST elevation. All patients were well at one year.A rise in tni is frequently observed during acute idiopathic pericarditis. According to the correlation with ST segment elevation, a rise in tni is apparently indicative of superficial myocardial damage. The prognostic value remains unknown.

Acute dissection of the aorta during myocardial infarction is exceptional. In such cases, fibrinolysis can be fatal.A 63-year-old woman with a history of hypertension was referred to our intensive care unit with the diagnosis of early stage inferior myocardial infarction. Thrombolysis was instituted and the patient rapidly developed cardiovascular collapse with global heart failure. Coronarography was attempted to revascularize the occluded coronary artery but the coronary arteries could not be catheterized. An aortography was performed and gave the diagnosis of De Bakey type I dissection of the aorta. The patient died from cardiac arrest after a phase of low cardiac output.This case illustrates how myocardial infarction can complicate or mask acute dissection of the aorta. It also raises the question of transthoracic echocardiography prior to institution of fibrinolysis.

This study was designed to prospectively evaluate the effects of radiofrequency ablation in Wolff-Parkinson-White (WPW) syndrome by scintigraphic analysis.The functional changes triggered by radiofrequency current ablation of atrioventricular accessory pathways are not fully known.Forty-four patients with WPW syndrome were consecutively investigated before and 48 h after radiofrequency therapy. Fourteen patients had right sided atrioventricular pathways and 30 patients had left sided bypass-tracts. Planar gated imaging and gated blood pool tomography were performed in all of these patients.A significant increase in the left ventricular ejection fraction (LVEF) was demonstrated in patients with left preexcitation (62.2+/-7.9% before ablation against 64.4+/-6.3% after ablation, p = 0.02) but not for those with right sided anomalous pathway. Phase analysis only gave significant differences following ablation of right sided pathways (left-to-right phase difference = 14.4+/-13.8 degrees before ablation versus 7.5+/-7.2 degrees after ablation, p0.05). Early abnormal ventricular contraction persisted in 12 patients with right accessory pathways and in 8 patients with left accessory pathways despite the complete disappearance of any abnormal conduction as proven electrophysiologically.Following catheter ablation of atrioventricular accessory pathways: 1) an improvement of left ventricular function may be seen, particularly in patients with left sided accessory pathways, and 2) unexpected persistence of local ventricular preexcitation at the site of successful ablation may be detected.

To evaluate prospectively, the tolerability and safety of intravenous cibenzoline therapy, for the cardioversion of spontaneous monomorphic ventricular tachycardia (VT).Between February 1990 and December 1996, fifty-eight patients aged 59+/-10 years old (fifty-three males, five females), with spontaneous VT not causing cardiac arrest, received intravenous cibenzoline. Their underlying heart conditions were: ischemic heart disease [35], dilated cardiomyopathy [14], right ventricular dysplasia [3], hypertrophic cardiomyopathy [1], valvulopathy [2], Fallot's Tetralogy [1] and primary arrhythmogenic disease [2]. The left ventricular ejection fraction was 42+/-13% (range 20%-76%).The mean dose of cibenzoline was 70+/-12 mg. The tachycardia stopped within 6+/-3 min in 47 (81%) patients. Side effects from cibenzoline occurred in two patients. The hemodynamic complications were limited to hypotension, that required vasopressor therapy in one patient. The only apparent proarrhythmic effect consisted of an isolated change in the morphology of the VT, that resolved spontaneously on withdrawal of the drug. No mortality occurred at the hospital.With appropriate rules for its administration, intravenous cibenzoline has the potential to become one of the first-line antiarrhythmic drugs, to be used for cardioversion of patients with spontaneous VT.

Objective—To compare the efficacy and safety of a single dose of ibutilide, a new class III antiarrhythmic drug, with that of DL-sotalol in terminating chronic atrial fibrillation or flutter in haemodynamically stable patients. Design—Double blind, randomised study. Setting—43 European hospitals. Patients—308 patients (mean age 60 years, 70% men, 48% with heart disease) with sustained atrial fibrillation (n = 251) or atrial flutter (n = 57) (duration three hours to 45 days) were randomised to three groups to receive a 10 minute infusion of 1 mg ibutilide (n = 99), 2 mg ibutilide (n = 106), or 1.5 mg/kg DL-sotalol (n = 103). Infusion was discontinued at termination of the arrhythmia. Main outcome measure—Successful conversion of atrial fibrillation or flutter, defined as termination of arrhythmia within one hour of treatment. Results—Both drugs were more effective against atrial flutter than against atrial fibrillation. Ibutilide was superior to DL-sotalol for treating atrial flutter (70% and 56% v 19%), while the high dose of ibutilide was more effective for treating atrial fibrillation than DL-sotalol (44% v 11%) and the lower dose of ibutilide (44% v 20%, p

Background —Infection remains a serious complication after permanent pacemaker implantation. Antibiotic prophylaxis is frequently prescribed at the time of insertion to reduce its incidence, although results of well-designed, controlled studies are lacking. Methods and Results —We performed a meta-analysis of all available randomized trials to evaluate the effectiveness of antibiotic prophylaxis to reduce infection rates after permanent pacemaker implantation. Reports of trials were identified through a Medline, Embase, Current Contents, and an extensive bibliography search. Trials that met the following criteria were included: (1) prospective, randomized, controlled, open or blind trials; (2) patients assigned to a systemic antibiotic group or a control group; (3) end point events related to any infection after pacemaker implantation: wound infection, septicemia, pocket abscess, purulent secretion, right infective endocarditis, inflammatory signs, a positive culture, septic pulmonary embolism, or repeat operation for an infective complication. Seven trials met the inclusion criteria. They included 2023 patients with established permanent pacemaker implantation (new implants or replacements). The incidence of end point events in control groups ranged from 0% to 12%. The meta-analysis suggested a consistent protective effect of antibiotic pretreatment ( P =.0046; common odds ratio: 0.256, 95% confidence interval: 0.10 to 0.656). Conclusions —Results of the present meta-analysis suggest that systemic antibiotic prophylaxis significantly reduces the incidence of potentially serious infective complications after permanent pacemaker implantation. They support the use of prophylactic antibiotics at the time of pacemaker insertion to prevent short-term pocket infection, skin erosion or septicemia.

Acute dissection of the aorta is an increasingly recognised pathology, the diagnosis of which is sometimes delayed despite the fact that advances in medical imaging provide almost perfect diagnostic accuracy. Some of the symptoms are particularly suggestive. Chest pain is the key symptom, and the greater the intensity, usually described as a migratory intrathoracic tearing sensation irradiating towards the lumbar region. The other symptoms become meaningful in association with this pain: paraplegia, acute peripheral ischaemia, hemiplegia. Clinical examination is capital when a diastolic murmur of aortic regurgitation is heard or when a distal pulse is absent, the blood pressure is asymmetric or a pericardial rub is detected. The frighteningly poor initial prognosis of acute dissection of the aorta has been transformed by surgery, providing, that it is performed early. Optimal therapeutic results can only be obtained by and early diagnosis.

Background: Valve obstruction is a life threatening complication of mechanical valve prosthesis. Methods: From 1985 to 1993, 29 consecutive patients were hospitalized in our intensive care unit for mechanical prosthetic valve thrombosis (PVT). There were 12 men and 17 women aged 25‐75 years (57912). Prosthetic valve location was mitral in 14 patients, aortic in 6, aortic and mitral in 9. PVT occurred from 15 days to 174 months (679 52 months) after surgery. Delay from first symptoms to hospitalization ranged from 1 to 45 days (11911). Results: First clinical symptoms were progressive left heart failure in 17 patients, stroke in 6, and chest pain in 6. Furthermore, acute myocardial infarction was later documented in 3. Left heart failure NYHA III‐IV was present in 26 patients (90%) on admission and 10 of those were in cardiogenic shock. Anticoagulation regimen was inadequate in 13 cases (45%). It has been recently stopped in 8 patients and incorrectly conducted in 5. Total hospital mortality was 41.3% (12). It was independent of type and position of the valve prosthesis. Diagnosis of PVT was only made at autopsy in 3 patients who died of recurrent myocardial infarction (2) or cardiogenic shock (1). Five further patients died before any surgery could be attempted (cardiac arrest: 2, cardiogenic shock: 3). Valve replacement could be done in 21 cases, 7 of whom were in cardiogenic shock and 9 had severe pulmonary edema. Four patients died after surgery, the operative mortality was 19%. Conclusion: PVT remains a serious complication of mechanical heart valve prostheses. Overall mortality rate is high, related to difficulty to diagnosis, delay to hospitalization and severe clinical condition at admission. In our study, operative risk remained acceptable even when the clinical presentation was severe. © 1997 Elsevier Science B.V.

The present study was performed to evaluate whether the modalities of risk stratification after myocardial infarction were still operative in the thrombolytic era.Prediction of fatal events in the aftermath of myocardial infarction relies on tests which aim to assess myocardial function, residual ischaemia and propensity for ventricular arrhythmias. Recent data on improved myocardial infarction prognosis have led to the view that risk stratification needs to be updated.In this multicentre, prospective study, 471 acute myocardial infarction patients, 45% of whom were given thrombolytic therapy, were enrolled from the 10th day and underwent all or part of the following tests exercise test, radionuclide ventriculography (resting and exertional ejection fraction). Holter monitoring, signal-averaged electrocardiography and programmed electrical stimulation. Univariate and multivariate analyses were performed to identify predictors of mortality.One year and long-term (mean follow-up 31.4 months) mortality rates were 5.5% and 8.4%, respectively. Prediction of mortality was assessed and the role of the following variables was thus determined: age over 56 years (P = 0.01), previous coronary attacks (P0.001), history of heart failure (P0.001), early heart failure after myocardial infarction (P = 0.017), maximum workload of lest than 120 W at exercise test (P = 0.014), ineligibility to perform exercise (P = 0.002), depressed left ventricular ejection fraction (P = 0.013), late potentials as identified using 50 Hz high pass filtering (P = 0.012), mean night-time cycle length of less than 750 ms (P0.001), standard deviation of day time RR intervals of less than 100 ms (P = 0.04), the last two measures reflecting heart rate variability. In this population, neither ventricular ectopic activity nor inducibility of sustained monomorphic ventricular tachycardia at electrophysiological study carried any prognostic significance. Multivariate analyses showed that decreased heart rate variability, presence of late potentials and low ejection fraction (30%) made an independent contribution to the survival models.In the current context of management of acute coronary patients, the basis for risk stratification after myocardial infarction remain roughly unchanged.

A good result of electrophysiological investigations under amiodarone therapy distinguishes a low risk group of patients with malignant ventricular arrhythmias. The authors set out to determine the factors predictive of this response in order to identify patients better protected by amiodarone at an earlier stage. Fourty-five patients with an average age of 56 years, were referred for evaluation of severe ventricular arrhythmias, monomorphic ventricular tachycardia being inducible during electrophysiological investigation in all cases before treatment. Amiodarone was prescribed orally at degressive doses. A control electrophysiological study was performed 4 to 6 weeks later. Eighteen patients (40%) were considered to be responders (absence of inducible ventricular arrhythmia or inducible non-sustained tachycardia or tachycardia with a cycle length increased by over 100 ms with respect to the base-line study). The other 27 patients were considered to be non-responders. No clinical or paraclinical parameter was found to distinguish responders from non-responders. The authors conclude that the data obtained before control electrophysiological investigation under amiodarone does not allow prediction of the response to this drug. The search for early prognosis of the efficacy of amiodarone in preventing ventricular arrhythmias therefore requires electrophysiological investigation after impregnation.

The authors report the case of a 63-year-old woman with occlusive thrombosis of a mitral valve prosthesis and cardiogenic shock successfully treated by systemic thrombolytic therapy. This treatment was given despite metastatic hepatic and bone breast cancer. This, and other recently reported cases, argues in favour of widening the indication of thrombolysis as treatment of first intention in cases of obstruction of atrioventricular valve prostheses. Nevertheless, the relative safety of surgical treatment and the risk of systemic thromboembolism of thrombolysis, incites caution and reservation of medical therapy for carefully selected patients.

Left ventricular aneurysms are usually secondary to myocardial infarction with atheromatous coronary artery disease. The authors report two rare cases of non-atheromatous left ventricular apical aneurysms. The first case was clearly post-traumatic but the diagnosis in the second case was more difficult. The authors discuss the aetiological diagnosis of these rare non-atheromatous aneurysms in adults and the therapeutic management with respect to these two cases and a review of the literature.

Patients with an implanted cardioverter defibrillator (ICD) may experience a certain degree of suffering. A sample of 32 patients was surveyed to determine the psychological benefit resulting from this treatment.Hamilton Anxiety Scale, Beck Depression Inventory and a shortened version of the Minnesota Multiphasic Personality Inventory were used. A 10-item scale and a global index of quality of life were especially designed to assess cardioverter defibrillator tolerance and the effect of its implantation on patients' current well-being.Both quality of life index scores were negatively correlated with anxiety and depression. Occurrence of shocks had no influence on psychological well-being.The questionnaires provided a simple and reliable measure of quality of life in ICD patients. Prior to implantation, technical explanations should be accompanied by stress management techniques adapted to the patients' psychological background.

The objective of this study was to compare the efficacy and safety of cibenzoline (130 mg twice a day) and sustained-release hydroquinidine (300 mg twice a day) in the prevention of recurrent atrial fibrillation (AF). This randomized double-blind study was conducted in 87 patients, with a mean age of 62 years, presenting with a history of AF for 72 hours to a maximum of 3 years. After restoration of sinus rhythm, in order for the subjects to be included in the study, echocardiography had to reveal a left ventricular shortening fraction of more than 20%. Patients were followed for one year by clinical examination, ECG and 24-hour Holter monitoring performed 7 days after inclusion, then after 3, 6, 9 and 12 months. The two groups, treated with either cibenzoline (n = 40) or hydroquinidine (n = 44), were comparable. The AF recurrence rates with cibenzoline or hydroquinidine were 34.9% had 36.4% at 6 months, and 41.9% and 43.2% at 12 months, respectively (NS). Most recurrences occurred during the first month. Adverse effects were reported in 10 patients (23.3%) with cibenzoline and 12 patients (27.3%) with hydroquinidine. They led to discontinuation of treatment in 6 patients (14%) treated with cibenzoline and 5 patients (11.4%) treated with hydroquinidine. Serious adverse events included one death from hypoglycaemic coma and one case of persistent ventricular tachycardia with hydroquinidine. In conclusion, oral cibenzoline demonstrated the same antiarrhythmic activity as hydroquinidine in the long-term prevention of recurrent atrial fibrillation, with a similar degree of safety. This drug can therefore constitute an alternative to conventional antiarrhythmics in this context.

The authors analysed the clinical and paraclinical variables of 116 patients admitted to the Hôpital Cardiologique de Lyon between 1986 and 1990 with sustained ventricular tachycardia without cardiocirculatory arrest in order to determine the long-term outcome and the prognostic factors of death and recurrence. The average age of the patients was 56 +/- 15 years (mean +/- SD) and 83% were men. The mean ejection fraction was 39 +/- 15%. Sixty-five had previous myocardial infarction (group I); 30 (group II) had dilated cardiomyopathy (n = 21), right ventricular dysplasia (n = 4), hypertrophic cardiomyopathy (n = 2), congenital (n = 2) or valvular (n = 1) heart disease. Group III comprised 21 patients with no apparent cardiac disease or isolated mitral valve prolapse. Brief syncope was reported in 12 cases. The paraclinical investigations showed 46 patients (66%) with at least two criteria of positivity for ventricular late potentials; Holter recording showed doublets or runs of VES in 46% of cases and sustained or non-sustained VT was induced during exercise testing in 16 patients (22%). Programmed ventricular stimulation triggered VT in 85%, 79% and 61% of patients in groups I, II and III respectively. The patients were treated with amiodarone in 65 cases, a betablocker in 25 cases, catheter ablation of the origin of the tachycardia in 12 cases, antiarrhythmic surgery in 6 cases, coronary bypass grafting in 5 cases (with an associated antiarrhythmic procedure in 3 cases). An automatic defibrillator was implanted in 9 patients. The average follow-up period was 32 months (range: 17 days to 65 months).(ABSTRACT TRUNCATED AT 250 WORDS)

Systematic transoesophageal echocardiography after the 10th day of mitral valve replacement with a mechanical prosthesis has enable diagnosis of several abnormal conditions: thrombi, strands and paravalvular leaks. The aim of this prospective study was to determine the prevalence of these conditions by biplane transoesophageal echocardiography in the first 24 postoperative hours. Transthoracic and transoesophageal echocardiography was performed on average 12 +/- 3 hours after coming out of the surgical block in 77 consecutive patients who underwent mitral valve replacement with a mechanical prosthesis. Nine patients (11.7%) had appearances of thrombi or strands in the left atrium or auricle. These small thrombi (1 to 1.5 cm2) were not obstructive. No embolic events were observed in the first month of these patients. Spontaneous contrast was seen in the left atrium of 31 patients (40%). The factors associated with the presence of thrombus or strands were advanced age (p = 0.02), presence of spontaneous contrast (p = 0.02) and more dilated left atrium (p = NS) Paraprosthetic leaks were seen in 11 cases (14.3%). In 10 cases, the regurgitant jets were narrow at their origin with little extension into the left atrium. Only one patient had severe regurgitation associated with raised transprosthetic pressure gradients. Cases with paravalvular leaks had a lower incidence of spontaneous contrast (3.2% vs 21.7%) and no thrombosis. Transoesophageal echocardiography demonstrated spontaneous contrast, thrombi and strands in the initial hours following implantation of a mechanical mitral valve prosthesis. The prevalence of these appearances, comparable to that of the results reported with later investigations, underlines the importance of effective anticoagulation from the fist postoperative hours.

The first radical approach to the treatment of atrioventricular nodal reentrant tachycardia was surgical dissection of the perinodal region. This technique has been replaced by the delivery of radiofrequency energy by an ablation catheter to the region of the atrioventricular node. The aim of this report is to describe the authors' experience of atrioventricular nodal application of radiofrequency current. The study comprised 53 cases (32 women and 21 men, mean age 46 +/- 17 years) with frequent attacks of reciprocating tachycardia. Endocavitary electrophysiological investigation confirmed the intranodal reentrant mechanism. The region of application of the radiofrequency current was located radiologically and then the precise site determined by the recording of nodal electrical activity. The appearance of junctional rhythm during the procedure was also used as a means of identification of the zone of ablation. Dual conduction persisted after ablation in 35 patients. However, no episode of tachycardia could be induced after the procedure. The AH interval increased during application of radiofrequency current in 3 cases but this abnormality regressed in the 2 months following the procedure. Recurrences of nodal reentrant tachycardia were observed in 14 cases (26%), 24 hours to 2 months after ablation. The rate of recurrence was significantly higher in patients who did not have a junctional rhythm during application of the radiofrequency current (62% vs 4%, p0.05). The number of recurrences was also greater in the group of patients with persistence of slow intranodal conduction after the radiofrequency ablation (p0.04). A second session of radiofrequency ablation was undertaken in 14 patients and a third session was required for 2 of them.(ABSTRACT TRUNCATED AT 250 WORDS)

A commensal organism of the buccal cavity, Actinobacillus actinomycetemcomitans (AAC) has been responsible for at least four new cases of infectious endocarditis by year in France. This retrospective study was based on 90 new cases of infectious endocarditis by AAC, including 8 personal observations. One third of patients had no known cardiac disease before their infectious endocarditis, the portal of entry of which was usually dental. In cases of suspected infectious endocarditis, rapid and severe weight loss (43% of cases) and, less commonly, anicteric cholestasis (8%) should alert the physician for the possible pathological role of AAC. The echocardiographic appearances are non-specific. The diagnosis is confirmed on blood cultures but the organism grows slowly in CO2 enriched atmosphere. Initially, the course of the disease was favourable in one third of patients but, in two thirds of cases, complications were observed almost renal (26%), cardiac (24%) and neurological (18%). Two thirds of patients were cured by the time they were discharged whereas the remainder had sequellae, mainly valvular and neurological. The hospital mortality was 9%; late mortality was 6%. Therefore, the prognosis of AAC endocarditis, seems to be better than that of other bacteriological forms. A combination of cephalosporin and aminoside, or even a simple third generation cephalosporin antibiotic therapy for at least 4 weeks are usually effective. The complementary surgical indications are the same as for other forms of infectious endocarditis. Prophylaxis depends on strict prophylactic amoxicillin therapy for all cardiac patients at risk of infectious endocarditis before dental treatment and on good bucco-dental hygiene.

The authors report the long term results of His bundle ablation for supraventricular tachycardia in a series of 49 patients. This retrospective study was based on a patient population of 27 men and 22 women with an average age of 59 at the time of ablation, between 1984 and 1993. The indication for His bundle ablation was invalidating supraventricular tachycardia resistant to antiarrhythmic therapy in all cases. One group of patients (Group I, n = 31 patients) underwent high energy electrical shock and the second group (Group II, n = 18 patients) recruited after 1991, underwent radiofrequency catheter ablation. Complete atrioventricular block was obtained in the first group in 1 to 4 sessions whereas 17 patients of Group II were treated in a single session. During a follow-up period of an average of 40 months, 2 patients were lost to follow-up and 6 died, 3 of cardiac failure, 1 of a cerebrovascular accident, 1 of pulmonary carcinoma and 1 of unknown cause. In Group I, atrioventricular conduction persisted in 1 patient (primary failure) and reappeared in one other patient, but, in Group II, complete atrioventricular block persisted even in the patient in whom the interruption was not obtained with a single session of radiofrequency ablation. The patients were generally physically improved and satisfied not to have any palpitations. A decrease in exercise capacity estimated by the NYHA classification was observed in 38% of patients without apparent cardiac disease who developed dyspnea. On the other hand, 43% of patients with cardiac disease and in NYHA classor = 2 were improved.(ABSTRACT TRUNCATED AT 250 WORDS)

Although the material and techniques of implantation of the electrodes of implantable defibrillators have been improved, the abdominal implantation of the generator remains widely used as described by Mirowski in 1980. Despite a progressive reduction in their size, the generators remain bulky and a source of local complications. The risks and discomfort of implantation in the abdominal wall led the authors to try subdiaphragmatic implantation in 22 patients. There was no morbidity with perfect healing in all 22 cases. The mean follow-up period was 11 months. The patients felt very comfortable, a significant advance with respect to abdominal implantations.

Nonthoracotomy lead systems are increasingly used in patients (pts) with implantable cardioverter defibrillator (ICD). In this setting, due to high energy requirements, a subcutaneous patch may be necessary in addition to endocardial leads. However in some patients, high defibrillation threshold (DT) may persist leading to thoracotomy for epicardial patch placement. In a preliminary experience, 3 patients with high DT (20 J) following endocardial lead system, underwent the insertion of a extrapericardial patch under video-thoracoscopic control. A left subcostal incision extended to the left pleural cavity was performed. Using thoracoscopy the patch was positioned on the pericardium, sutured and connected to the defibrillator. DTs were 10, 10 and 20 J respectively in our 3 patients. Postoperative course was uneventful. Thoracoscopy allows other techniques such as a stellectomy, which we performed in a 33 year old woman with long QT syndrome. Patients were reassessed after 8 days and 2 months. Termination of induced ventricular fibrillation was achieved with the same minimal energy levels used peroperatively. In conclusion, extrapericardial patch insertion using thoracoscopy may help reduce DT in ICD patients with a non thoracotomy lead system. Comparison with other lead configurations requires further investigation.

In order to identify patients who will receive an electric shock after implantation of an automatic fibrillator, the relationship between the time to the first shock and clinical and paraclinical characteristics were studied in 43 patients treated at the Lyon Cardiological Hospital between July 1987 and September 1991. The age of the patients was 49.5 +/- 16 years (mean + SD). Eighty two percent of patients were men and the average left ventricular ejection fraction was 38.5 +/- 16.8%. Four patients died in the peri-operative period. The average follow-up of the survivors was 22 months. During this period, 21 patients (53.8%) received an appropriate electric shock. Three patients died. The causal role of a malignant ventricular arrhythmia is discussed in one case. A second patient, who never had automatic fibrillation, died of cardiac failure. Finally, the third patient died of non-cardiac pathology. The 22 month actuarial survival rate was 86%. The probability of receiving an appropriate electric shock was 60%. Analysis of clinical and paraclinical features identified left ventricular dysfunction (ejection fraction less than 38%) and cardiac symptoms (Stage III dyspnoea of the NYHA classification) as being associated with earlier electric shocks. This association was even more clear cut in the group of patients with previous myocardial infarction. Therefore, patients with implantable automatic defibrillators for malignant ventricular arrhythmias receive appropriate electric shocks in over 50% of cases. Patients with symptoms of cardiac failure and low ejection fraction are particularly exposed especially when they have previous myocardial infarction.

Fifteen patients with acute myocardial infarction and cardiogenic shock underwent emergency cardiac transplantation after medical treatment failed to improve their haemodynamic status. Their mean age was 49 +/- 7 years. The infarction was anterior in 12 cases, inferoposterior in two cases, and septal in one. Shock occurred within 3 days after the onset of chest pain in nine patients, and during the first day in six of them. Mechanical circulatory assistance was used in six patients as a bridge to transplantation when their haemodynamic status could not be stabilized pharmacologically. Orthotopic cardiac transplantation was performed an average of 15.6 +/- 14 days after onset of infarction. Three patients died during the early post-operative period. Another died 7 months after transplantation. During the mean follow-up period of 30.6 +/- 20.3 months, there were three acute rejections, all successfully treated, and one chronic rejection. The survival rate for this series is 70%. Thus, emergency cardiac transplantation may be the best option for selected patients with acute myocardial infarction and cardiogenic shock refractory to conventional therapy.

From December 1990 to April 1992, 41 consecutive patients (22 men and 19 women with an average age of 35 +/- 16 years -6-72) underwent ablation of accessory atrioventricular conduction pathways (Bundles of Kent) for poorly tolerated and/or medically resistant supraventricular tachycardias. In 33 cases, the arrhythmia was a paroxysmal SVT, in 7 cases atrial fibrillation, and in 1 patient incessant junctional tachycardia causing left ventricular dysfunction. The Wolff-Parkinson-White syndrome was apparent in 30 patients and concealed in 11 cases. The location of the Kent bundle was left lateral in 22 cases (53.7%), posterior paraseptal in 9 cases (21.9%), right lateral in 5 cases (12.2%) and anterior paraseptal in 5 cases (12.2%). The Kent bundles were ablated by radiofrequency currents in 38 cases (92.7%); in 2 patients (4.9%) in whom radiofrequency could not be used (increased impedance) high energy electrical shock was successful. In one patient (2.4%), it was not possible to suppress the Kent bundle. A single session of radiofrequency ablation was sufficient in 33 cases: 7 cases (17.5%) required 2 (4) or 3 (3) sessions. The average number of sites of application per patient was 8.8 +/- 8.8. The duration and intensity were respectively 32.2 +/- 9.3 (5-60) seconds and 25 +/- 15 (20-30) watts. With an average follow-up of tachycardia or of ventricular preexcitation have been observed in the 40 patients. In addition, in 36 patients, electrophysiological control studies confirmed the initial result with absence of any disturbance of nodohisian conduction.(ABSTRACT TRUNCATED AT 250 WORDS)

The authors studied the clinical, angiographic and electrophysiological features, and the long-term outcome of patients with arrhythmogenic right ventricular dysplasia (ARVD). The study was retrospective and involved 22 patients (3 women and 19 men) with an average age of 36 years at the time of their first documented ventricular tachycardia (VT) and admitted to hospital between 1971 and 1989. The diagnosis of ARVD was based on the association of monomorphic VT with a left bundle branch block morphology and right ventricular abnormalities on angiography. Fifteen patients were treated by antiarrhythmic drugs alone, 5 by antiarrhythmic drugs and tachycardia ablation and 2 by antiarrhythmic drugs and cardiac transplantation. An automatic defibrillator was implanted in one patient. After the first episode of VT, the beginning of follow-up, the criteria of evaluation were mortality, right heart failure and the evolution of the arrhythmia. The study population had the following characteristics. Familial forms or ARVD were observed in 18%. The mitral ventricular arrhythmia was often induced by exercises (45%). Twenty-one patients had a sustained VT and 1 patient had non-sustained VT. The resting ECG in sinus rhythm was abnormal in all cases. Thirty-two different VT morphologies were recorded. The abnormalities of the right ventricular wall motion on ventriculography were localised in 45% of cases and diffuse in 55% of cases. Seventy per cent of patients undergoing electrophysiological investigation had inducible sustained VT. The clinical outcome after an average of 10.7 years' follow-up was: 17 survivors, 3 sudden deaths and 4 cases of right ventricular failure. The 10 year actuarial survival rate was 75%.(ABSTRACT TRUNCATED AT 250 WORDS)

Nonthoracotomy lead systems are increasingly used in patients (pts) with implantable cardioverter defibrillator (ICD). In this setting, due to high energy requirements, a subcutaneous patch may be necessary in addition to endocardial leads. However in some patients, high defibrillation threshold (DT) may persist leading to thoracotomy for epicardial patch placement. In a preliminary experience, 3 patients with high DT (20J) following endocardial lead system, underwent the insertion of a extrapericardial patch under video-thoracoscopic control. A left subcostal incision extended to the left pleural cavity was performed. Using thoracoscopy the patch was positioned on the pericardium, sutured and connected to the defibrillator. DTs were 10, 10 and 20 J respectively in our 3 patients. Postoperative course was uneventful. Thoracoscopy allows other techniques such as a stellectomy, which we performed in a 33 year old woman with long QT syndrome. Patients were reassessed after 8 days and 2 months. Termination of induced ventricular fibrillation was achieved with the same minimal energy levels used peroperatively. In conclusion, extrapericardial patch insertion using thoracoscopy may help reduce DT in ICD patients with a non thoracotomy lead system. Comparison with other lead configurations requires further investigation.

The authors attempted to identify the parameters which best differentiated intranodal reentry from tachycardias associated with an accessory pathway during a simplified electrophysiological study. The data were obtained by using two catheters, one recording right atrial activity and the other delivering programmed stimulation in the right ventricle. Sixty-four patients in whom the mechanism of their tachycardias had previously been determined were studied. There were 19 intranodal and 45 accessory pathway tachycardias. The following parameters were studied: the ventriculo-atrial interval during tachycardia; the prematurity of atrial activity in response to programmed ventricular stimulation; the shortest ventriculo-atrial interval when the atrial activity was premature; the difference between the shortest ventriculo-atrial interval with atrial prematurity and the ventriculo-atrial interval during tachycardia; in the absence of prematurity the ventriculo-atrial interval with the shortest ventricular coupling was used. The ventriculo-atrial interval during tachycardia was shorter in intranodal reentry (43 ms vs 170 ms, p less than 0.001). This interval was greater than 120 ms only in accessory pathway tachycardias and was only under 75 ms in patients with intranodal tachycardias. Premature atrial activation was observed in 42% of intranodal and 98% of accessory pathway tachycardias (p less than 0.001). The predictive value for tachycardias involving an accessory pathway was 85% when the auriculogramme was premature and, conversely, it was 92% for intranodal tachycardia.(ABSTRACT TRUNCATED AT 250 WORDS)

To avoid atrioventricular node-His bundle ablation, catheter ablation of the atrial myocardium was attempted in eight patients with drug refractory type I atrial flutter. In seven of eight patients, a zone of prolongation and fragmentation of the endocardial electrogram was found in the low posterior part of the right atrium. Entrainment of the atrial flutter by high right atrial pacing was accompanied by local recording of second-degree regional block in several atrial sectors but never in the low septal area. We, therefore, hypothesized that the latter represented the critical slow conduction zone of the reentrant flutter circuit. One or two cathodal DC shocks were locally delivered without immediate or late complications. One single ablation attempt was performed in five patients, whereas three patients underwent a second attempt because of early flutter recurrence. Patients were initially discharged without (and after a second session with) antiarrhythmic drugs. After a mean follow-up of 15.5 months (range, 10-23 months), five patients are free of arrhythmias without antiarrhythmic drug therapy. Two patients did not experience atrial arrhythmias while on a drug regimen that was previously found to be ineffective, and a third patient had flutter recurrences. This study suggests that patients with type I atrial flutter referred for atrioventricular node-His bundle ablation may be successfully managed by delivering the ablative shock directly on the atrial arrhythmia substrate.

Electrophysiologic studies were performed in three patients suffering from attacks of paroxysmal tachycardia with wide QRS complexes. Two patients had atrioventricular dissociation. The arrhythmia could be initiated and terminated by premature ventricular stimulation in all three patients. One patient developed the arrhythmia after rapid atrial stimulation. In each subject, the QRS complexes during tachycardia were identical to recorded supraventricular beats (left bundle branch block pattern in two cases and right bundle branch block pattern in one). A His bundle potential was noted before the QRS complex; the HV interval was equal to or longer than that of the sinus beats. The following observations suggested the presence of a bundle branch reentry mechanism: (1) the relationship between bundle branch block development and tachycardia initiation; (2) the occurrence of tachycardia after electrically induced His-Purkinje reentry; (3) the ability of premature ventricular stimulation during tachycardia to advance the timing of the His deflection and QRS complex, with an unchanged or slightly increased HV interval; and (4) the termination of arrhythmia by premature ventricular depolarization blocked within the bundle branch system. Our results support the idea that bundle branch reentry can play a role in the genesis of ventricular tachycardia.

The effects of amiodarone on the sinuatrial node were studied in 24 patients after an intravenous injection of the drug (5 mg/kg). Sinuatrial function was assessed by rapid atrial pacing and premature atrial stimulation. Sinus cycle length did not change significantly, but the corrected sinus node recovery time was prolonged. While there was no significant change in sinuatrial conduction time, prolongation of the non-reset zone in 14 cases, as well as the abolition of the platesu in 2/24 patients, suggested that conduction of the atrial responses to the sinus node might have been depressed.