RESUMO
UNLABELLED: Renal denervation using the technique of radiofrequency is used only recently for the treatment of resistant hypertension. Normally, it is done under general anesthesia because the ablation point technique is painful. We suggest an alternative to general anesthesia comprising an association of morphin 0.1mg/kg IV to MEOPA (gas combining oxygen and azot protoxyd) delivered through an oxygen mask. Our series includes 12 consecutive patients treated between October 2011 and June 2013, the first five patients (group 1) have received only an hydroxizin and morphin sedation. Every five have felt the ablation painful, in two cases bearable pain (EVA<5), in three cases intense (EVA>5) pain leading to increasing doses of morphin, (total dose of 0.25mg/kg in two cases, 0.17mg in one case). For the seven following patients, a protocol including hydroxyzin, morphin and MEOPA given through a mask has been set up. Only one patient has felt a mild pain (EVA 5) leading to an increasing dose of morphin (total dose 0.17mg/kg). None of the six other patients has felt any pain during the procedure. The average dose of morphin is 0.17mg/kg in group 1, 0.11mg/kg in group 2. This is a preliminary study; if confirmed, it will allow a lot of hospitals without on-site possibilities of general anesthesia, to realize such procedures. CONCLUSION: regarding pain, the procedure of renal ablation was well tolerated for six among seven patients receiving the association MEOPA and IV morphin. In contrast, in the five patients treated only with IV morphin, we observed a less good tolerance to pain and the need to increase the doses of IV morphin.
Assuntos
Analgésicos não Narcóticos/administração & dosagem , Analgésicos Opioides/administração & dosagem , Ablação por Cateter/métodos , Denervação/métodos , Morfina/administração & dosagem , Óxido Nitroso/administração & dosagem , Compostos de Oxigênio/administração & dosagem , Artéria Renal/cirurgia , Idoso , Ablação por Cateter/efeitos adversos , Combinação de Medicamentos , Feminino , Humanos , Hipertensão/cirurgia , Masculino , Pessoa de Meia-Idade , Dor/etiologia , Dor/prevenção & controle , Medição da DorRESUMO
OBJECTIVES: To assess the prevalence of coronary artery spasm during dobutamine stress chocardiography (DSE), to describe clinical and echocardiographic characteristics and prognosis. PATIENTS AND METHODS: We evaluated all the patients with known or suspected coronary artery disease (CAD) referred to our echocardiography laboratory for dobutamine stress test between January 2004 and June 2012, (10013 exams). Those with abnormal DSE underwent coronary angiograms with a systematic methylergometrine intracoronary injection in case of absence of significant coronary stenosis or spontaneous occlusive coronary spasm. Patients who had spontaneous occlusive coronary spasm or positive methylergometrine test but no significant stenoses were included. RESULTS: One thousand and four patients had abnormal DSE, 78 (7.7%) fulfilled the inclusion criteria. There were 57 males and 21 females, mean age was 57.9 years, 37 patients had a known history of CAD. Twenty-four patients had a spasm on the left anterior artery (31%), 37 on the right coronary artery (47%) and 17 on the circumflex (22%). There was a good correlation between spastic arteries and dobutamine induced wall motion abnormalities territories. No complications occurred during the exams or during the provocation test. After 46 months mean follow up; one case of myocardial infarction with normal coronary arteries was noted and six patients experienced recurrent angina responding to treatment intensification. CONCLUSION: Coronary artery spasm during DSE but is a rare and under-diagnosed finding; it has, though, to be recognized as it may partly explain some erroneously labelled "false positive" exams. Methylergometrine provocation test should be performed in such a situation to establish the diagnosis. Prognosis appears favourable.
Assuntos
Cardiotônicos/efeitos adversos , Doença da Artéria Coronariana/diagnóstico por imagem , Estenose Coronária/diagnóstico por imagem , Vasoespasmo Coronário/induzido quimicamente , Vasoespasmo Coronário/epidemiologia , Dobutamina/efeitos adversos , Ecocardiografia sob Estresse/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Angiografia Coronária/métodos , Reações Falso-Positivas , Feminino , Seguimentos , França/epidemiologia , Humanos , Injeções Intravenosas , Masculino , Metilergonovina , Pessoa de Meia-Idade , Ocitócicos , Valor Preditivo dos Testes , Prevalência , Prognóstico , Estudos Prospectivos , Sensibilidade e EspecificidadeAssuntos
Anestesia Epidural/métodos , Anestesia Obstétrica/métodos , Raquianestesia/métodos , Cesárea , Emergências , Obesidade Mórbida/complicações , Complicações na Gravidez , Adulto , Anestesia Epidural/instrumentação , Falha de Equipamento , Feminino , Sofrimento Fetal , Humanos , Lordose/etiologia , Agulhas , Gravidez , Complicações Cardiovasculares na Gravidez/etiologia , Tromboflebite/etiologiaRESUMO
The efficacy of propafenone in the treatment of paroxysmal atrial fibrillation was investigated in 16 patients presenting with frequent and/or poorly tolerated paroxysmal atrial fibrillation despite prophylactic treatment in 13 patients. Prolonged atrial fibrillation (> 10 minutes) was triggered in 16 patients following a standard atrial stimulation protocol. Intravenous injection of propafenone (2 mg/kg over 5 minutes) restored sinus rhythm in 12 patients (75%) within 15 minutes after the end of the injection. In five of the 10 patients in whom this was possible, propafenone prevented the induction of atrial fibrillation in response to programmed stimulation by the same protocol. Oral propafenone (900 mg/24 hours) was indicated in 11 patients. The treatment was discontinued in 1 patient due to severe dizziness. Atrial fibrillation recurred in 4 patients 10 to 91 days after treatment began. With a mean follow-up time of 8 months, 4 patients had been brought under control and 2 had relapsed despite a generally beneficial effect. Three patients suffered side effects which did not make it necessary to stop treatment. This study suggests that intravenous propafenone is effective against persistent atrial fibrillation induced by stimulation. Oral propafenone may be useful for the prevention of attacks of recalcitrant paroxysmal atrial fibrillation.
Assuntos
Fibrilação Atrial/tratamento farmacológico , Propafenona/uso terapêutico , Administração Oral , Adolescente , Adulto , Idoso , Fibrilação Atrial/prevenção & controle , Tontura/etiologia , Avaliação de Medicamentos , Feminino , Humanos , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade , Propafenona/administração & dosagem , Propafenona/efeitos adversosRESUMO
The efficacy of antiarrhythmic drugs is attributed to their actions on the refractory periods or conduction velocity in the reentry circuit. The aim of this study was to determine the relationship between these factors and the prevention of electrically inducible ventricular tachycardia (VT). Twenty-seven patients with sustained monomorphic postinfarction VT underwent programmed stimulation under basal conditions and after administration of oral Class I antiarrhythmic drugs. The protocol of stimulation consisted of delivering one to three extrastimuli to the right ventricular apex on two basic cycle lengths. Sustained VT was induced in all patients. After the same protocol under antiarrhythmic therapy (1 to 5 tests, average 2.9 +/- 1) sustained VT could not be induced in 12 patients (44%). The effective right ventricular refractory period was significantly increased in patients without inducible VT under treatment (247 +/- 18 versus 302 +/- 26 ms). The increase in the right ventricular effective refractory period in patients with persistence of inducible VT was much less (from 270 +/- 28 to 287 +/- 30 ms). In all patients in whom several antiarrhythmic drugs were tested the right ventricular effective refractory period was higher when the treatment was judged to be effective (299 +/- 27 ms) than ineffective (272 +/- 27, p < 0.02). The prevention of inducible VT by class I antiarrhythmic agents seems therefore to be related to their effect on the ventricular refractory period.
Assuntos
Antiarrítmicos/farmacologia , Estimulação Cardíaca Artificial , Sistema de Condução Cardíaco/efeitos dos fármacos , Taquicardia Ventricular/prevenção & controle , Antiarrítmicos/uso terapêutico , Feminino , Humanos , Masculino , Função Ventricular Direita/efeitos dos fármacosRESUMO
The aim of this study was to assess the usefulness of prophylactic antibiotics during insertion of a cardiac pacemaker, in order to avoid infection of exteriorisation of infectious origin. The study involved two groups. One hundred and eight patients made up group I, a control group without the use of prophylactic antibiotics. Group II consisted of 101 patients who were given an intravenous injection of 1 or 2 g of oxacillin before surgery, followed up by four days of oral oxacillin (3 g per day). Serum oxacillin levels at the end of the procedure were 0.37 +/- 0.09 mcg/ml, falling within the range of minimum inhibitory concentrations of methicillin-sensitive staphylococci. In the patients of the control group, followed up for 1 to 36 months (mean 12 +/- 11 months), during the first 2 months there were 2 infections, 4 exteriorisations and one cutaneous erosion over the pacemaker. In addition, one exteriorisation and one infection occurred at 17 and 29 months respectively. In patients with exteriorisation of their pacemaker device, there was nothing to suggest an infection and bacteriological specimens were sterile. No obvious infections nor any cutaneous complications occurred in the patients of group II, with prophylactic antibiotics, followed up for 1 to 21 months (mean 6 +/- 5 months). In conclusion, anti-staphylococcal antibiotic treatment appears not only to be capable of avoiding cardiac pacemaker infections but also of preventing exteriorisation of the pacemaker device, which may be linked to hidden infections. A randomised study is nevertheless necessary to confirm this hypothesis.
Assuntos
Antibacterianos/uso terapêutico , Marca-Passo Artificial , Pré-Medicação , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Avaliação como Assunto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de RiscoRESUMO
The etiology of syncope of presumed cardiac origin can be determined by clinical and electrocardiographic examination with Holter monitoring in about 50 per cent of cases. The aim of this study was to review the data of electrophysiological investigation and the outcome of the patients in whom a cardiac pacemaker was eventually implanted, in those cases in whom the initial work-up had been negative. Ninety four patients, all of whom underwent standardised electrophysiological investigation, were included. The results of the investigations enabled us to identify three groups of patients: Group I: patients in whom the criteria did not suggest a cardiac origin of syncope; Group II: with criteria possibly suggesting a cardiac origin and Group III in which the criteria were strongly suggestive of a cardiac origin. A cardiac pacemaker was implanted systematically for AV block in Group III; on the other hand, this was very rare (only 1 patient) in Group I, and the indication in Group II depended on age and the history of recurrent syncope. Ninety patients (96%) were followed up for an average of 39.3 +/- 15.3 months. There was a very low incidence of recurrent syncope irrespective of the original classification, so confirming the value of electrophysiological investigations for cardiac pacemaker implantation in this type of patients. In addition, negative electrophysiological investigations allowed identification of a group of patients with a low mortality and low risk of recurrent syncope.
Assuntos
Arritmias Cardíacas/complicações , Síncope/fisiopatologia , Idoso , Antiarrítmicos/uso terapêutico , Arritmias Cardíacas/fisiopatologia , Arritmias Cardíacas/terapia , Estimulação Cardíaca Artificial , Eletrocardiografia Ambulatorial , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Síncope/etiologiaRESUMO
A prospective study was carried out from May 1984 to July 1987 to determine the prognostic value of the results of programmed electrical stimulation (PES) in patients with complex ventricular ectopy. The study population comprised 118 patients, 80 with and 38 without apparent underlying cardiac disease. The PES consisted in at most 3 extrastimuli delivered to the right ventricular apex during 2 imposed basal rhythms. Two groups of patients were identified: Group I (n = 35; 29.6%) in which a significant ventricular arrhythmia was induced (sustained ventricular tachycardia (11 cases), non-sustained VT (21 cases) and ventricular fibrillation (3 cases); and Group II (n = 83; 70.3%) in which no significant arrhythmia could be induced. During follow-up (average 28.7 +/- 11.7 months, range 6 to 48 months) there were 10 cardiac deaths, 8 of which occurred suddenly. Sudden death only occurred in patients with cardiac disease and usually with LV ejection fraction of less than 0.40; the prevalence of sudden death in Group I (11.5%) was higher than in Group II (4.8%) but the difference was not statistically significant. The prognosis of patients in Group II was the same as that of the general population. The results of this study suggest that PES enables identification of a subgroup of patients with complex ventricular ectopy in which ventricular tachyarrhythmias cannot be induced and the risk of sudden death is low; the management of patients with inducible ventricular tachyarrhythmias and normal LV function has to be determined case by case.
Assuntos
Complexos Cardíacos Prematuros/terapia , Morte Súbita , Terapia por Estimulação Elétrica , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antiarrítmicos/uso terapêutico , Complexos Cardíacos Prematuros/complicações , Complexos Cardíacos Prematuros/fisiopatologia , Estudos de Avaliação como Assunto , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Fatores de RiscoRESUMO
The authors report the case of a 23 year old man who presented with a continuous murmur five years after closed chest trauma. The electrocardiographic and echocardiographic findings indicated previous apical myocardial infarction. The underlying diagnosis was first suggested by continuous wave Doppler which showed systolo-diastolic flow in the septo-apical region directed towards the left ventricle (LV) in diastole. Color Doppler flow studies showed a mosaic pattern opposite a dilated left anterior descending (LAD) artery. These signs of LAD-LV fistula with a single orific were confirmed at coronary arteriography. The patient's previous history was in favour of a traumatic etiology. In the absence of left ventricular failure and myocardial ischaemia by coronary steal, surgery was deferred; Doppler echocardiography would seem to be a good method of following up the fistula and its consequences on left ventricular function. A traumatic left coronary to left ventricular fistula is an extremely rare condition and merits publication. The authors review the literature and describe the physiopathology, diagnosis and therapeutic indications of these fistulae.
Assuntos
Vasos Coronários/lesões , Fístula/etiologia , Traumatismos Cardíacos/etiologia , Ventrículos do Coração/lesões , Traumatismos Torácicos/complicações , Adulto , Ecocardiografia , Fístula/diagnóstico , Traumatismos Cardíacos/diagnóstico , Sopros Cardíacos , Humanos , Masculino , UltrassonografiaRESUMO
A new technique for cardioversion of chronic atrial fibrillation was used in 17 patients whose arrhythmia had resisted all attempts at electrical and pharmacologycal cardioversion. Atrial fibrillation was badly tolerated by all patients despite digitalis administered alone (8 patients) or combined with amiodarone (9 patients). Twelve patients had left atrial dilatation at echocardiography. The 200, 300 or 400 joule electrical shock was delivered between the proximal pole of a quadripolar catheter (cathode) and a back plate (anode). The catheter was positioned at the His bundle recording site then withdrawn into the right atrium. The internal shock restored sinus rhythm in 15 patients (88 p. 100). Transient atrioventricular block (3-315 sec) was observed in 8 patients. Eleven patients were discharged in sinus rhythm. In 4 patients, the atrial fibrillation recurred on day 8 and after 2, 4 and 9 months. A second shock was attempted in two patients and succeeded in one. After a mean follow-up period of 14.8 +/- 8 months (range 2 to 25 months), 8 of the 11 patients successfully cardioverted (72 p. 100) or of the attempted reductions (47 p. 100) were in sinus rhythm. The remaining 9 patients were treated with antiarrhythmic drugs (n = 5) or by his bundle catheter ablation (n = 4). High energy internal shock therefore seems to be an interesting treatment in patients with permanent atrial fibrillation after failure of external electric shock. It enabled 13 of the 17 patients in this series to avoid His bundle catheter ablation indicated by the quasi-impossibility to control the atrial rate and associated symptoms.(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Fibrilação Atrial/terapia , Cardioversão Elétrica/métodos , Adulto , Idoso , Eletrocardiografia , Eletrocardiografia Ambulatorial , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , RecidivaRESUMO
Between 1977 and 1987, 27 consecutive patients (16 men, 11 women, mean age 66 years, range 54 to 75 years) with ventricular septal rupture complicating acute myocardial infarction underwent surgical repair. The purpose of this retrospective study was to analyse the post-operative mortality factors from clinical, haemodynamic and operative data in all patients and also from coronary angiographic data in 23/27 patients whose haemodynamic status allowed this type of exploration. Seventeen patients (63 p. 100) died during the first post-operative month, 10 survived and were discharged. Factors that influenced the prognosis were: (1) inferiorly-located necrosis associated with a 75 p. 100 mortality rate (9 out of 12 patients), as opposed to 53 p. 100 (8 out of 15 patients) with anterior necrosis; (2) right ventricular dysfunction, observed in 83 p. 100 of patients with inferior necrosis and 53 p. 100 with anterior necrosis, which was responsible for 7 out of 9 deaths in the inferior necrosis subgroup and contributed to 3 out of 8 deaths in the anterior necrosis subgroup; this established a cause-effect relationship between right ventricular function and the overmortality of patients with inferior necrosis; (3) independently of the haemodynamic status, two- and three-vessel lesions (56 p. 100 of all lesions) which had an 84 p. 100 mortality rate as opposed to 40 p. 100 with one-vessel lesions; (4) the presence of a state of shock which was associated with a 78 p. 100 mortality rate as opposed to 55 p. 100 in patients without shock. We conclude that when permitted by the patient's haemodynamic status coronary angiography should be part of the pre-operative evaluation to assess the operative risk and guide the surgical procedure.
Assuntos
Ruptura Cardíaca Pós-Infarto/cirurgia , Ruptura Cardíaca/cirurgia , Doença Aguda , Idoso , Angiografia Coronária , Feminino , Ruptura Cardíaca/mortalidade , Ruptura Cardíaca Pós-Infarto/mortalidade , Hemodinâmica , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Choque Cardiogênico/fisiopatologiaRESUMO
Seventy-two consecutive patients with electrocardiographic evidence of Wolff-Parkinson-White syndrome underwent electrophysiological study (EPS). Fifty-five of these patients (76 p. 100) had episodes of tachycardia, 11 experienced palpitations or syncopes and 6 were asymptomatic. The decision to prescribe an antiarrhythmic agent was reached on the basis of the patients' symptoms and EPS data. One patient was treated by surgery before the medical treatment was tried; 17 patients were discharged without treatment, 4 were discharged with an episodic and 50 with a preventive antiarrhythmic treatment. Among these 50 patients, 46 (92 p. 100) could be followed up for a mean period of 45.7 +/- 28 months. One died of lung cancer; 43 presented with spontaneous episodes of tachycardia, 4 were able to discontinue treatment at the end of the follow-up period since they had very few symptoms and 2 were lost sight of. Among the 37 patients under antiarrhythmic treatment followed up, 29 (78 p. 100) are well controlled, while 8 (22 p. 100) still present with episodes of tachycardia. A tachycardia-reducing pacemaker was implanted in 5 of these 8 patients. It therefore appears that 78 p. 100 of patients presenting with spontaneous episodes of tachycardia associated with WPW syndrome can be controlled with an antiarrhythmic treatment. This result was obtained after trying at least two types of antiarrhythmic agents in 86 p. 100 of the cases.(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Antiarrítmicos/uso terapêutico , Taquicardia/tratamento farmacológico , Síndrome de Wolff-Parkinson-White/tratamento farmacológico , Adolescente , Adulto , Eletrofisiologia , Feminino , Seguimentos , Sistema de Condução Cardíaco , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Taquicardia/etiologia , Síndrome de Wolff-Parkinson-White/complicações , Síndrome de Wolff-Parkinson-White/fisiopatologiaRESUMO
The electrocardiographic characteristics of spontaneous escape rhythm during complete heart block induced by transcatheter ablation of the atrioventricular junction was prospectively studied in 21 patients by periodically interrupting temporary pacing. The data derived from 13 of these 21 patients, in whom conduction recurred after the procedure, were analyzed. An escape rhythm was present in 12 patients 8.2 +/- 5.8 minutes after shock delivery at a cycle length of 1985 +/- 974 ms. The escape QRS had a configuration of right bundle branch block with left axis deviation in 9 patients, of right bundle branch block with normal axis in 1, of left bundle branch block with left axis deviation in 1, and 2 distinct morphologies in the remaining patient. After resumption of conduction, the conducted complexes were identical to the escape complexes in six patients, different only in axis in four patients, and different in morphology in two patients. This suggests that in the majority of patients the escape rhythm seen during transient heart block, induced by transcatheter ablation of the atrioventricular junction, presents a right bundle branch morphology with or without a left axis deviation, and most likely originates from an area above, or close to, the site of the anatomical damage.
Assuntos
Arritmias Cardíacas/cirurgia , Eletrocardiografia , Sistema de Condução Cardíaco/cirurgia , Coração/fisiopatologia , Adulto , Idoso , Arritmias Cardíacas/fisiopatologia , Eletrocirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
The incidence and significance of ventricular arrhythmia induced by programmed electrical stimulation in subjects with complex ventricular ectopy were studied in 46 consecutive subjects: 34 with heart disease, 12 with an apparently normal heart. The procedure consisted of delivering on one spontaneous and 2 imposed rhythms one, two, then three extrastimuli. Significant arrhythmia with more than 6 ventricular complexes was induced in 17 patients (37%), including 6 (13%) with sustained ventricular tachycardia and 11 with unsustained ventricular tachycardia. Induction of ventricular arrhythmia was observed in 12 of the 14 patients with a history of myocardial infarction. At the end of a mean follow-up period of 12 +/- 4 months, there were 2 sudden deaths, and 3 patients had clinically sustained ventricular tachycardia. Clinical ventricular tachycardia occurred in the group of 17 patients inducible during programmed electrical stimulation. The patients who died suddenly belonged to the group of 29 patients without induced ventricular arrhythmia. This study shows a high proportion of significant stimulation-induced arrhythmia in patients who had suffered from myocardial infarction more than 3 months previously and who had complex ventricular ectopy. Owing to the good condition of this group of patients after a mean follow-up of 12 months, we were unable to determine the influence of stimulation-induced arrhythmia on mortality. However, it must be noted that spontaneous sustained tachycardia occurred in the group of patients with significant induced ventricular arrhythmia.
Assuntos
Complexos Cardíacos Prematuros/fisiopatologia , Estimulação Cardíaca Artificial , Adulto , Idoso , Antiarrítmicos/uso terapêutico , Complexos Cardíacos Prematuros/tratamento farmacológico , Doença das Coronárias/fisiopatologia , Morte Súbita , Eletrocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica , Prognóstico , Estudos ProspectivosRESUMO
Falipamil hydrochloride (AQA 39) is a new antiarrhythmic agent structurally related to verapamil. We evaluated the electrophysiologic properties of intravenous falipamil (1.5 mg kg-1 within 20 minutes) in 12 patients. The spontaneous cycle length was significantly (P less than 0.001) prolonged (+79 +/- 59 ms). Atrioventricular conduction was significantly (P less than 0.001) shorter due to AH interval shortening (-17 +/- 14 ms), most probably related to an anticholinergic effect. Similarly, the anterograde Wenckebach point occurred at a significantly (P less than 0.06) higher rate after falipamil (+10 +/- 7 beats min-1). No statistically significant effect was noted on the refractory periods of the AV node, although there was a trend to shortening. The refractoriness of the right atrium and ventricle was significantly prolonged. It is concluded that falipamil is a bradycardiac agent with electrophysiologic properties quite different from those of verapamil and similar to those of class IA antiarrhythmic agents.
Assuntos
Antiarrítmicos , Coração/efeitos dos fármacos , Ftalimidas/farmacologia , Idoso , Nó Atrioventricular/efeitos dos fármacos , Doença das Coronárias/fisiopatologia , Eletrofisiologia , Feminino , Átrios do Coração/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Ventrículos do Coração/efeitos dos fármacos , Humanos , Isoindóis , Masculino , Pessoa de Meia-IdadeRESUMO
The mode of termination by programmed electrical stimulation of sustained ventricular tachycardia (VT) (more than 30 seconds) and induced by stimulation was investigated in 33 patients. In 27 patients (82%) programmed stimulation was possible because VT did not require an immediate electric shock or did not terminate spontaneously, but constant reduction of VT was obtained with one extrasystole in only 1 patient (3%), with two extrasystoles in 5 patients (15%) and by overdrive stimulation in 12 patients (36%). The remaining 15 patients (45%) required an external electric shock either because VT was poorly tolerated clinically, or because stimulation had failed. In 8 of the 27 cases in whom stimulation was attempted (30%), acceleration of VT was observed. A significant correlation was found between the need for electrical shock and the VT cycle length. It is concluded that reduction of VT by programmed electrical stimulation can only be successful in a limited number of patients and carries a significant risk of acceleration. These data must be taken into account when temporary treatment of VT by stimulation is contemplated. They should incite to considerable caution in the use of implantable pacemakers for tachycardia termination.
Assuntos
Terapia por Estimulação Elétrica/métodos , Taquicardia/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Ventrículos do Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Taquicardia/fisiopatologiaRESUMO
We report on two patients out of a series of 22 who underwent transcatheter ablation of the atrioventricular (AV) junction. The procedure failed to induce permanent complete heart block in 15 patients, 12 of whom were in sinus rhythm with 1:1 AV conduction before hospital discharge. Of the 12 patients, two (16.6%) were found to be in high degree heart block, one month later. We discuss the mechanism of late occurrence of high degree heart block and we emphasize the need for systematic implantation of permanent ventricular or dual chamber pacemakers, despite failure of transcatheter ablation of the AV junction.
Assuntos
Fibrilação Atrial/cirurgia , Fascículo Atrioventricular/cirurgia , Estimulação Cardíaca Artificial , Bloqueio Cardíaco , Sistema de Condução Cardíaco/cirurgia , Taquicardia Supraventricular/cirurgia , Adulto , Fibrilação Atrial/fisiopatologia , Cateterismo Cardíaco , Eletrocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Taquicardia Supraventricular/fisiopatologiaRESUMO
The presence of resting sinus bradycardia (less than or equal to 45 bpm) with junctional escapes in an 8 year old child with catecholamine induced ventricular tachycardia, raised the problem of an underlying sinus node dysfunction. This was an important consideration bearing in mind the potential risk of the high dose betablocker therapy aggravating the sinus bradycardia. Electrophysiological studies showed pathological sinus node recovery times. Betablocker therapy did not aggravate the bradycardia, even after 6 months' treatment. A review of the literature showed the association of sinus bradycardia and catecholamine-induced ventricular tachycardia to be relatively common (39 p. 100). However, no mention was found of aggravation of this sinus bradycardia by betablocker therapy.