Klinika kardiologie IKEM, Praha. firstname.lastname@example.org
[Clinical spectrum of ventricular tachycardias]. [Review] [40 refs] [Czech]
Casopis Lekaru Ceskych. 139(18):557-63, 2000 Sep 13.
Substantial information has been accumulated concerning the mechanisms, electrocardiographic patterns and electrophysiologic characteristics of various ventricular tachycardias. As a result, several distinct clinical entities of ventricular tachycardia can be identified, each of them with different manifestation, prognostic importance and management strategies. Among monomorphic tachycardias, the sustained ventricular tachycardia after myocardial infarction is the most frequent form, accounting for more than 70% of all ventricular tachycardias. Monomorphic ventricular tachycardias are less frequently associated with dilated or hypertrophic cardiomyopathy, arrhythmogenic right ventricular dysplasia and other diseases. Distinct entity that should not go unrecognised is the bundle branch re-entry and/or interfascicular re-entry. Finally, there is a heterogeneous groups of idiopathic ventricular tachycardias occurring in patients without hay structural heart disease. Polymorphic ventricular tachycardias are often associated with either congenital or acquired QT interval prolongation, the so called torsade de pointes arrhythmias. In addition, some polymorphic ventricular tachycardias without QT interval prolongation may be triggered by ischaemia and/or can occur in patients with previous myocardial infarction. The review describes all the most important varieties of monomorphic and polymorphic ventricular tachycardias together with the treatment options. [References: 40]
Bodegas A. Arana J. Rumoroso JR. Rodrigo D. Barrenetxea JI.
Department of Cardiology, Hospital de Cruces, Barakaldo, Basque Country, Spain.
Prognosis of patients with a first episode of sustained monomorphic ventricular tachycardia.
International Journal of Cardiology. 65(2):181-5, 1998 Jul 1.
: AIMS: To evaluate the cardiac mortality in patients suffering from a first episode of sustained monomorphic ventricular tachycardia (SMVT). METHODS: 100 patients less than 75 years old were evaluated during a 50-month follow-up period. Patients were classified into four groups: myocardial infarction, dilated cardiomyopathy, normal heart and miscellany. Seventeen patients underwent a cardioverter-defibrillator implantation, two heart transplant, three aneurysmectomy and 10 other types of cardiac surgical proceedings. RESULTS: Patients with a left ventricle ejection fraction (EF)> or =50% presented a cardiac mortality of 5% compared with 38% of those with EF<50%. Etiology of underlying cardiomyopathy with an EF> or =50% was associated with a cardiac mortality of 5% (normal heart), 5% (myocardial infarction) and 9% (miscellany) compared to those with EF<50%: 33% (dilated cardiomyopathy) and 40% (myocardial infarction). Patients who experienced syncope during the first episode of SMVT showed a cardiac mortality of 31% compared to those 14% (P < 0.05) who did not experience. Patients with syncope, myocardial infarction and EF<50% showed a cardiac mortality of 68%. CONCLUSION: The present study shows that survival after the first episode of SMVT is closely related to EF and the existence of syncope. Patients with myocardial infarction and EF<50% had a worse prognosis when the site was the inferior wall.
Gradel C. Jain D. Batsford WP. Wackers FJ. Zaret BL.
Section of Cardiovascular Medicine, Yale University School of Medicine, New Haven, CT 06510, USA.
Relationship of scar and ischemia to the results of programmed electrophysiological stimulation in patients with coronary artery disease.
Journal of Nuclear Cardiology. 4(5):379-86, 1997 Sep-Oct.
BACKGROUND: Although myocardial perfusion imaging (MPI) is widely used in patients with coronary artery disease, few data are available concerning the relationship between myocardial scar and ischemia and arrhythmic potential. PATIENTS AND METHODS: One hundred forty-four patients with chronic coronary artery disease who underwent electrophysiological studies (EPS) and MPI within 3 months constituted the study population. By history, 26% of the patients had sustained ventricular tachycardia (VT), 21% had cardiac arrest with ventricular fibrillation, and 53% had nonsustained VT. Eighty-five percent had previous myocardial infarction. Standard EPS protocol with up to three extra stimuli was used. Patients with a response of sustained monomorphic VT were defined as inducible. Quantitative MPI was used to define stress perfusion defect size and reversibility. The relations of ischemia (reversible defect) and scar (fixed defect) to inducibility on EPS were assessed by univariate analysis. Multivariate analysis was used to compare MPI results with known clinical predictors of inducibility. RESULTS: Fifty-two percent of the patients had inducible monomorphic sustained VT. MPI showed scar alone in 33%, scar with additional ischemia in 53%, ischemia alone in 8%, and no abnormality in 6%. No relation was found between the scintigraphic presence or size of ischemia and the likelihood of inducibility or to the type of arrhythmia history. In contrast, scar size was related to the result of EPS; inducible patients had significantly larger resting defect integrals (27 +/- 23 vs 14 +/- 15) than noninducible patients (p < 0.0001). Of 37 patients with very large defects (defect integral > 30), 78% were inducible, whereas only 30% of 33 patients with defect integrals < 5 were inducible. On multivariate analysis resting defect integral was an independent predictor of inducibility. In comparison with left ventricular ejection fraction (available in 122 patients), perfusion defect size was a better independent predictor of sustained VT on EPS. CONCLUSION: The presence or size of potentially ischemic myocardium does not appear to be related to the inducibility during EPS. Size of scar as quantified by myocardial perfusion imaging correlates well and better than the global left ventricular function with inducibility of sustained VT on EPS.
Mont L. Cinca J. Blanch P. Blanco J. Figueras J. Brotons C. Soler-Soler J.
Servicio de Cardiologia, Hospital General Universitari Vall d'Hebron, Universitat Autonoma de Barcelona, Spain.
Predisposing factors and prognostic value of sustained monomorphic ventricular tachycardia in the early phase of acute myocardial infarction.
Journal of the American College of Cardiology. 28(7):1670-6, 1996 Dec.
OBJECTIVES: The purpose of the study was to analyze the factors that favor the occurrence of sustained monomorphic ventricular tachycardia in the early phase (< 48 h) of acute myocardial infarction and to establish its prognostic implications. BACKGROUND: Sustained monomorphic ventricular tachycardia early in the course of an acute myocardial infarction is an uncommon arrhythmia, and its significance has not been specifically studied. METHODS: The clinical characteristics and prognosis of sustained monomorphic ventricular tachycardia were studied in 21 (1.9%) of 1,120 consecutive patients admitted to the coronary care unit with a diagnosis of myocardial infarction. RESULTS: Patients with sustained monomorphic ventricular tachycardia had a larger infarct on the basis of peak creatine kinase, MB fraction (CK-MB) isoenzyme activity (435 +/- 253 IU/liter vs. 168 +/- 145 IU/liter, p < 0.001) and higher mortality rate (43% vs. 11%, p < 0.001). By logistic regression analysis, in dependent predictors of sustained monomorphic ventricular tachycardia were CK-MB (odds ratio [OR] 11.8), Killip class (OR 4.0) and bifascicular bundle branch block (OR 3.1). Moreover, sustained monomorphic ventricular tachycardia was itself an independent predictor of mortality (OR 5.0). Compared with patients with ventricular fibrillation, those with sustained monomorphic ventricular tachycardia had a worse Killip class (Killip class > I: 63% vs. 30%, p < 0.05), higher CK-MB activity (430 +/- 260 IU/liter vs. 242 +/- 176 IU/liter, p < 0.01) and higher arrhythmia recurrence rate (31% vs. 4%, p < 0.01). During the follow-up period, 5 (42%) of 12 survivors in the sustained monomorphic ventricular tachycardia group died of cardiac-related causes. Recurrence of ventricular tachycardia was seen in two patients (17%). CONCLUSIONS: Sustained monomorphic ventricular tachycardia during the first 48 h of myocardial infarction is a sign of extensive myocardial damage and an independent predictor of in-hospital mortality.