Surgical management of ventricular tachyarrhythmias

Surgical treatment of cardiac arrhythmias

This report describes 20 consecutive patients who underwent surgical procedures for treatment of cardiac arrhythmias. 16 patients have been operated for WPW syndrome, always using the epicardial approach, without extracorporeal circulation. Three patients underwent surgery for atrio-ventricular nodal reentrant tachycardia, using a discrete perinodal cryotreatment, during normothermic extracorporeal circulation. In one case we used cryoablation of the atrial myocardium below the coronary sinus to treat atrial flutter. This operation was performed under normothermic extracorporeal circulation. In our observations, there was no early or late death; postoperative complications developed in 1 patient (5%) due to pericarditis. Ablation of the AP was completely successful in all the cases (100%) operated for WPW as well as for AVNRT syndromes and atrial flutter.

Bundle branch reentrant tachycardia treated by transvenous catheter ablation of the right bundle branch

Recurrent episodes of ventricular tachycardia not responding to medical treatment occurred in a 56-year-old man. Electrophysiological investigation showed ventricular tachycardia due to bundle branch reentry. Using a method similar to catheter ablation of the atrioventricular junction, ablation of the right bundle branch was performed by an electrical shock of 250 joules. While before the ablation ventricular tachycardia occurred several times a day and its induction by programmed ventricular stimulation was facilitated by the administration of antiarrhythmic drugs, no initiation of ventricular tachycardia was possible after ablation of the right bundle branch. Over a follow-up of 30 months the patient has not suffered from tachycardia and the right bundle branch block persists.

The prognostic value of the changes in the mode of ventricular tachycardia induction noted during therapy with a marked reduction of ventricular ectopic activity

The prognostic significance of changes in the mode of induction of ventricular tachycardia (VT) noted during therapy was studied in 49 patients with sustained VT or ventricular fibrillation. Before treatment, all patients had inducible sustained VT by programmed stimulation (one to three extrastimuli) and frequent (greater than or equal to 30/hr) ventricular premature complexes (VPCs). On the discharge regimen, VT was no longer inducible by programmed stimulation in 22 patients (group 1). Twenty-seven patients (group 2) with persistent induction of VT despite extensive serial drug testings were discharged on a regimen that resulted in a marked reduction of VPCs on Holter monitoring (greater than or equal to 50% reduction of VPCs, greater than or equal to 90% reduction of couplets, and abolition of nonsustained VT). The modes of induction at baseline and on the discharge regimen were compared in each patient in group 2. Induction of VT was more difficult, requiring more aggressive stimulation protocol in 5 of 27 patients, unchanged in 14 patients, and easier in 8 patients. The duration of follow-up was 20 +/- 13 months (mean +/- SD). Arrhythmia-free survival rates at 6, 12, 18, and 24 months were 95%, 89%, 82%, and 73% in group 1, 92%, 84%, 75%, and 75% in group 2, 93%, 83%, 77%, and 69% in 27 patients with noninducibility or harder induction, and 95%, 90%, 79%, and 79% in 22 patients with the same or easier induction, respectively. The differences were not significant.(ABSTRACT TRUNCATED AT 250 WORDS)

Laser-assisted endocardiectomy for refractory ventricular tachyarrhythmias: preliminary intraoperative experience

Previous in vitro investigations utilizing necropsy specimens have suggested a potential role for laser irradiation in the treatment of refractory ventricular tachyarrhythmias associated with pathologically thickened endocardium. In the patient described in the present report, findings of these previous in vitro studies were applied intraoperatively to a patient undergoing surgery for ischemic heart disease associated with ventricular tachyarrhythmias. Aneurysm resection and manual subendocardial resection were performed using standard techniques. Laser irradiation was used to ablate pathologically thickened endocardium involving the papillary muscle and thereby avoid mitral valve replacement. Postoperatively, there was no auscultatory evidence of mitral regurgitation, and ventricular tachycardia could not be induced by electrophysiologic provocative testing. This preliminary experience confirms that laser irradiation is both a feasible and potentially advantageous means of accomplishing endocardial debridement in patients undergoing arrhythmia-ablation procedures.

Is programmed stimulation of value in predicting the long-term success of antiarrhythmic therapy for ventricular tachycardias?

We studied the value of programmed stimulation in assessing the efficacy of antiarrhythmic agents in 52 patients with sustained ventricular tachycardia. All patients in this nonrandomized study had ventricular tachycardia inducible by programmed stimulation and also had frequent ventricular premature complexes (greater than or equal to 30 per hour) on Holter-monitor recordings before therapy. The efficacy of antiarrhythmic agents was assessed by both programmed stimulation and Holter recordings during serial drug testing. A regimen was deemed effective according to the programmed-stimulation criteria in 25 patients (Group 1). Twenty-seven patients in whom tachycardia could still be induced during programmed stimulation despite extensive drug trials were discharged on a regimen that caused a marked reduction of ventricular premature complexes according to Holter monitoring (Group 2). In 23 patients no effective drug regimen was identified by either set of efficacy criteria, and these patients were excluded from the present analysis. Follow-up lasted 18.6 +/- 13.9 months. Rates of arrhythmia-free survival at 12 and 24 months were 88 percent and 72 percent, respectively, in Group 1 and 84 percent and 75 percent in Group 2 (P = 0.637). We conclude that demonstration of antiarrhythmic efficacy by programmed stimulation predicts a good clinical outcome, that inefficacy as shown by the programmed-stimulation protocol used in this study may not preclude a good outcome if there is a marked reduction of spontaneous ventricular premature complexes on Holter monitoring, and that randomized trials should be conducted to validate the results of this observational study.

Clinical, angiographic, and electrophysiologic findings in patients with aborted sudden death as compared with patients with sustained ventricular tachycardia after myocardial infarction

After the acute phase of myocardial infarction, patients who develop sustained ventricular arrhythmias present with either sudden death or ventricular tachycardia (VT). Although current evidence suggests that VT frequently precedes ventricular fibrillation (VF) in patients presenting with sudden death, the factors resulting in rapid deterioration of VT to VF have not been delineated in humans. To determine whether left ventricular function, coronary anatomy, or electrophysiologic characteristics could differentiate patients with sudden death from those with VT without sudden death, we compared results of cardiac angiography and programmed electrical stimulation in 42 patients referred for evaluation of sustained VT or surviving "aborted" sudden death for more than 9 days after myocardial infarction. By univariate analysis there were no differences between patients with sudden death and those with VT in age, time from myocardial infarction to VT or sudden death, ejection fraction (0.31 +/- 0.12 vs 0.29 +/- 0.09), or the number of patients with a major area of contracting myocardium supplied by an artery with a 50% or greater or a 70% or greater stenosis (84% vs 64% and 68% vs 41%). Thirty-six percent of patients with sudden death but no patient with VT had two separate areas of infarction. During programmed electrical stimulation, a sustained ventricular arrhythmia was initiated in 100% of patients with VT and 73% of patients with sudden death and rapidly produced syncope in 67% of patients with sudden death but in only 5% of those with VT. This difference was due to the more frequent initiation of rapid polymorphic VT or VF (27% of patients) and to the shorter VT cycle length (242 +/- 31 vs 319 +/- 69 msec) when monomorphic VT was induced in the group with sudden death. No difference was found in the number of extrastimuli required for initiation of a sustained ventricular arrhythmia.(ABSTRACT TRUNCATED AT 250 WORDS)

Laser photoablation of pathological endocardium: in vitro findings suggesting a new approach to the surgical treatment of refractory arrhythmias and restrictive cardiomyopathy

In selected patients, malignant ventricular tachyarrhythmias have been successfully abolished by excision of subendocardial arrhythmogenic foci. Likewise, in certain patients in whom restrictive cardiomyopathy is due to endocardial thickening, endocardial resection has resulted in hemodynamic improvement. The present study was designed to explore the utility, in vitro, of laser photoablation of pathologically thickened endocardium. Endocardial photoablation was easily accomplished regardless of etiological or anatomical variations using either the focused beam of a carbon dioxide laser or argon laser light delivered through a 200-microns optical fiber. Photoablation of areas as large as 3.9 X 1.3 cm was performed within 40 seconds. The extent or depth of endocardial photoablation could be limited to 2 mm2 in area or 1 mm in depth using either form of laser therapy. These in vitro results suggest that either carbon dioxide or argon laser phototherapy can be successfully applied to the surgical treatment of refractory arrhythmias and restrictive cardiomyopathy. Advantages of laser photoablation include speed and precision. Furthermore, laser photoablation obviates the difficulty associated with conventional techniques in establishing tissue planes.

Operative therapy for ventricular arrhythmia

The history of surgical attempts to control ventricular arrhythmia is reviewed and current methodology is presented in detail. The results of the various surgical approaches and future trends in the management of this troublesome condition are discussed.