Comparison of standard aneurysmectomy and aneurysmectomy with directed endocardial resection for the treatment of recurrent sustained ventricular tachycardia

Outcomes of Catheter Ablation of Ventricular Tachycardia in the Setting of Structural Heart Disease

Sustained ventricular tachycardias are common in the setting of structural heart disease, either due to prior myocardial infarction or a variety of non-ischemic etiologies, including idiopathic dilated cardiomyopathy, hypertrophic cardiomyopathy, and arrhythmogenic right ventricular cardiomyopathy. Over the past two decades, percutaneous catheter ablation has evolved dramatically and has become an effective tool for the control of ventricular arrhythmias. Single and multicenter observational studies as well as several prospective randomized trials have begun to investigate long-term outcomes after catheter ablation procedures. These studies encompass a wide range of mapping and ablation techniques, including conventional activation mapping/entrainment criteria, substrate modification guided by pacemapping, late potential and abnormal electrogram ablation, scar de-channeling, and core isolation. While large-scale, multicenter prospective randomized clinical trials are somewhat limited, the published data demonstrate favorable outcomes with respect to a reduction in overall ventricular tachycardia (VT) burden, reduction of implantable cardioverter defibrillator (ICD) shocks, and discontinuation of anti-arrhythmic medications across varying disease subtypes and convincingly support the use of catheter ablation as the standard of care for many patients with VT in the setting of structural heart disease.

Analytic Reviews: Electrophysiologic Testing in the Intensive Care Unit

The role of electrophysiologic concepts and procedures in managing patients with potentially life-threatening ar rhythmias in the intensive care unit is discussed. These patients may be survivors of sudden cardiac arrest or myocardial infarction or may be admitted for syncope or sustained or nonsustained ventricular tachycardia. The value of electrophysiologic testing is discussed in terms of the distinction between wide QRS complex tachycardias that are supraventricular or ventricular in origin and those in which preexcitation syndromes may be important. Drug-induced ventricular arrhythmias are discussed, with specific emphasis on torsades de pointes. Finally, the use of His bundle recordings in pa tients with atrioventricular conduction disturbances is discussed. The methodology of electrophysiologic test ing, including stimulation protocols and interpretation of results, is described.

Surgical ventricular reconstruction with endocardectomy along radiofrequency ablation-induced markings

OBJECTIVE

The objective of this study was to evaluate the efficacy of a novel approach for endocardectomy during coronary artery bypass graft with surgical ventricular restoration in patients with postinfarction left ventricular aneurysm.

METHODS

One hundred sixty-eight patients underwent coronary artery bypass graft with surgical ventricular restoration from 2005 to 2011. Endocardectomy was performed as an integral part of surgical ventricular restoration for the prevention of ventricular tachycardia. The experimental group (surgical ventricular restoration-endocardectomy group; n = 74) underwent preoperative electrophysiologic study with electroanatomic left ventricular mapping. Radiofrequency ablation-induced markings were placed and were used later as guides for performing endocardectomy during coronary artery bypass graft with surgical ventricular restoration. The control group (surgical ventricular restoration group; n = 94) underwent surgical ventricular restoration without endocardectomy.

RESULTS

The 1-year mortality rates in the surgical ventricular restoration-endocardectomy and surgical ventricular restoration (control) groups were 5% and 13%, respectively. During the postoperative period, 3% of patients in the surgical ventricular restoration-endocardectomy group and 38% of patients in the surgical ventricular restoration group experienced ventricular tachycardia events (P < .05). Automatic implantable cardioverter-defibrillators were implanted in 11 patients in the surgical ventricular restoration group and in 1 patient of the surgical ventricular restoration-endocardectomy group for secondary prevention of sudden cardiac death.

CONCLUSIONS

When performed as an integral part of surgical ventricular restoration, endocardectomy was crucial in preventing postoperative ventricular tachycardia. Use of radiofrequency ablation-induced markings allowed clear visualization of the reentry zones for efficient endocardectomy during coronary artery bypass graft with surgical ventricular restoration, resulting in better patient outcomes.

Surgery for ventricular tachycardia in patients undergoing surgical ventricular restoration: The Karolinska approach

This article presents a review on the efficacy of surgical ventricular restoration and direct surgery for ventricular tachycardia in patients with left ventricular aneurysm or dilated ischemic cardiomyopathy. The procedure includes a non-electrophysiologically guided subtotal endocardiectomy and cryoablation in addition to endoventricular patch plasty of the left ventricle. Coronary artery bypass surgery and mitral valve repair are performed concomitantly as needed. In our experience, this procedure yielded a 90% success rate in terms of freedom from spontaneous ventricular tachycardia, with an early mortality rate of 3.8%. A practical guide to the pre- and postoperative management of these patients is provided.

Surgery and ablative therapy for ventricular tachycardia

In the absence of acute ischaemia, ventricular tachycardia (VT) is the most common arrhythmia leading to cardiac arrest and death. This paper will describe the history of research into VT and the therapies that evolved. The contributions of John Uther and other members of the Department of Cardiology at Westmead Hospital will be outlined and placed into perspective.

Relationship Between Successful Ablation Sites and the Scar Border Zone Defined by Substrate Mapping for Ventricular Tachycardia Post-Myocardial Infarction

INTRODUCTION

It is unknown if identification of scar border zones by electroanatomical mapping correlates with successful ablation sites determined from mapping during ventricular tachycardia (VT) post-myocardial infarction (MI). We sought to assess the relationship between successful ablation sites of hemodynamically stable post-MI VTs determined by mapping during VT with the scar border zone defined in sinus rhythm.

METHODS AND RESULTS

Forty-six patients presenting with hemodynamically stable, mappable monomorphic VT post-MI and who had at least one such VT successfully ablated were prospectively included in the study. In each patient, VT was ablated by targeting regions during VT that exhibited early activation, +/- isolated mid-diastolic potentials, and concealed entrainment suggesting a critical isthmus site. Prior to ablation, a detailed sinus-rhythm CARTO voltage map of the left ventricle was obtained. A voltage <0.5 mV defined dense scar. Successful VT ablation sites were registered on the sinus voltage map to assess their relationship to the scar border zone. Of the 86 VTs, 68% were successfully ablated at sites in the endocardial border zone. The remaining VTs had ablation sites within the scar in (18%), in normal myocardium (4%), and on the epicardial surface (10%). There were no significant differences in VT recurrence amongst the different groups.

CONCLUSION

Successful ablation sites of hemodynamically stable, monomorphic VTs post-MI are often located in the scar border zone as defined by substrate voltage mapping. However, in a sizable minority, ablation sites are located within endocardial scar, epicardially, and even in normal myocardium.

[Endocardial ablation of substrate of postinfarction ventricular tachycardia during sinus rhythm]

OBJECTIVE

Radiofrequency ablation of ventricular tachycardia requires good tachycardia tolerance during mapping and entrainment, and this limits its application. We present our initial experience with ventricular tachycardia ablation during sinus rhythm in 7 patients with previous inferior myocardial infarction.

METHODS

Seven men, 56-70 years old (mean +/- SD, 65 +/- 4.5) were included in the study. Ventricular tachycardia was unstable in 6 and in 1 it was induced non-sustained. The scar was localized by recording low-voltage, fragmented electrograms (< 2 mV). Ventricular tachycardia "exit" was localized by pace-mapping in sinus rhythm. Radiofrequency lines were made radially, point by point, from normal to scarred tissue. One of the lines crossed the exit area. The objective was to achieve non-inducibility.

RESULTS

Sustained clinical ventricular tachycardia was induced in 6 and non-sustained in 1. Two-four lines were performed per patient with 11-28 (21 +/- 5.4) radio frequency applications. The procedure duration was of 130-280 min (230 +/- 61) and being 49-75 min (63 +/- 7.9) for fluoroscopy. There were no complications. Clinical ventricular tachycardia became non-inducible in 6, although in 4 a rapid (cycle < or = 250 ms), non-clinical ventricular tachycardia remained inducible. Defibrillators were implanted in the patient remaining inducible for clinical ventricular tachycardia and another with > 60 tachycardia episodes the previous week. During 3-22 months (13.8 +/- 5.9) of follow-up, 1 patient died of heart failure at 20 months and another received 3 defibrillator shocks for VT at 13 months. There were no other episodes of ventricular tachycardia, syncope or sudden death.

CONCLUSIONS

This preliminary experience suggests that radiofrequency ablation of post-infarction ventricular tachycardia substrate is possible during sinus rhythm, suggesting that radiofrequency ablation may be applicable in a large proportion of patients with post-infarction sustained ventricular tachycardia.

Mapping of septal ventricular tachycardia: clinical and experimental correlations

In patients with chronic myocardial infarction, ventricular tachycardia originating in the interventricular septum may account for a significant number of arrhythmia recurrences after direct ablative operations. We used total computer-assisted cardiac mapping (epicardial sock, left and right ventricular endocardial balloon electrode arrays) to assess whether tachycardia originating in deep or right-sided layers of the interventricular septum is associated with a specific pattern of epicardial activation sequence. We performed these studies during operations in 18 patients and during experiments in 12 dogs in which a septal myocardial infarction was produced by ligating the anterior septal coronary artery. Intraseptal needle electrodes were plunged into the septum of all animal preparations to generate pace-mapping data and to obtain intraseptal recordings (six preparations) during reentrant ventricular tachycardia induced by programmed stimulation. In addition, pace-mapping data of infarcted canine heart preparations were compared with those of nine healthy heart preparations. In the clinical study, 31 ventricular tachycardias with a septal site of origin were analyzed. Twenty tachycardias displayed an epicardial breakthrough in the area of the interventricular groove, whereas 11 had an epicardial breakthrough in the right ventricular free wall. Biventricular endocardial mapping revealed that left septal endocardial activation preceded right septal activation in the former and that right septal activation occurred earlier in the latter. In the experimental study, 14 ventricular tachycardias (cycle length 146 +/- 34 msec) were induced by programmed stimulation in 11 infarcted heart preparations. Eight tachycardias displaying an epicardial breakthrough on the right ventricle were found to originate in the right ventricular septal subendocardial layers, whereas six tachycardias in which the epicardial breakthrough occurred on the anterior interventricular groove originated in the left ventricular septal subendocardial layers. The epicardial breakthrough preceded the left ventricular endocardial breakthrough in six tachycardias (85.7%) originating in intermediate or right ventricular septal layers, but in only one of five tachycardias originating in the left ventricular septal layers. In the pace-mapping study, the epicardial breakthrough shifted progressively from the right ventricular free wall toward the interventricular groove area in response to pacing from the right, intermediate, and left ventricular thirds of the basal septum. This relationship was similar for infarcted and noninfarcted hearts, although transseptal conduction time was prolonged in infarcted hearts (45 +/- 10 msec vs 33 +/- 7 msec, p < 0.01). Therefore the information integrated from the localization of the epicardial breakthrough and the relative timing between the epicardial and the left ventricular endocardial breakthroughs can be used to estimate the depth of the site of origin of septal ventricular tachycardias. This study confirms that a three-dimensional view of the substratum of ventricular tachycardia can be derived from simultaneous epicardial and left ventricular endocardial mapping and can provide a superior basis for therapeutic interventions.

Postinfarction ventricular aneurysms

Ventricular aneurysms are circumscribed, thin-walled fibrous, noncontractile outpouchings of the ventricle. The majority are apically located, true aneurysms of the left ventricle (LV) that occur as a consequence of transmural myocardial infarction (MI). The precursor of aneurysm formation appears to be infarct expansion early after acute MI and occurrence generally relates to infarct size. The presence of underlying hypertension and the use of steroids and nonsteroidal antiinflammatory agents may promote aneurysm formation. The clinical sequelae include congestive heart failure (CHF), thromboembolism, angina pectoris, and ventricular tachyarrhythmias. Late rupture is a particular complication of false aneurysms in which the pericardium is the aneurysm wall. The diagnosis may be suspected by the clinical finding of a diffuse, pansystolic apical thrust, persistent ST-segment elevation on the electrocardiogram, and distortion of the cardiac silhouette on chest x-ray. This can be confirmed using echocardiography, radionuclide ventriculography, and cardiac catheterization. The latter has the additional advantage of being able to delineate the coronary anatomy. Management involves prevention, specific therapy for the various clinical manifestations, and surgery. Therapeutic interventions with thrombolytic agents, aspirin, heparin, and beta blockers that are applied early in the evolution of an MI may limit infarction size, thereby reducing the tendency toward infarct expansion and aneurysm formation. Patients with mild CHF can usually be controlled with the standard combination of angiotensin-converting enzyme inhibitors, diuretics, and digoxin. Thromboembolism is best prevented by anticoagulation with warfarin for at least 3 months after the acute MI. The choice of pharmacotherapy for ventricular tachyarrhythmias should be guided by electrophysiologic studies. The treatment of patients with angina pectoris utilizes conventional therapeutic modalities.(ABSTRACT TRUNCATED AT 250 WORDS)

Arrhythmogenic ventricular aneurysms unrelated to coronary artery disease

Malignant ventricular tachycardia occurs most frequently in patients with coronary artery disease who have had a previous myocardial infarction and in whom a ventricular aneurysm subsequently develops in the scarred section of myocardium. Ventricular tachycardia in the presence of normal coronary arteries and a left ventricular aneurysm is unusual and can be refractory to medical therapy. We retrospectively reviewed our experience of 10 patients treated at our institution from 1983 to 1993. Age ranged from 22 to 76 years, and all patients presented with sustained ventricular tachycardia. All patients underwent complete electrophysiologic testing. Cardiac catheterization was performed in 9 patients, and each had normal coronary artery anatomy without evidence of significant fixed lesions. A left ventricular aneurysm, diagnosed by either echocardiography, thoracic cine computed tomography or magnetic resonance imaging, or ventricular angiography was present in all patients. Ventricular tachycardia could not be suppressed pharmacologically in 7 of 10 patients using multiple agents including procainamide, quinidine, flecanide, tocainide, propaferone, and amiodarone. Six patients were treated surgically by intraoperative electrophysiologic mapping, endocardial resection of foci, and left ventricular aneurysmectomy. An implantable cardiac defibrillation device was implanted in 2 patients. One patient died on the second postoperative day after simultaneous mapping -guided aneurysmectomy and implantable cardioverter defibrillator placement. There was one late postoperative death. All other surgically treated patients had postoperative electrophysiologic studies demonstrating no inducible ventricular tachycardia, and these patients remain without antiarrhythmic therapy in follow-up extending from 29 to 86 months (mean, 56 months).(ABSTRACT TRUNCATED AT 250 WORDS)

Human ventricular tachycardia: precise intraoperative localization with potential distribution mapping

Electrophysiologically guided operations for ventricular tachycardia (VT) have been directed exclusively by activation time maps. Even with computer-assisted mapping, extensive editing is required, which prolongs the duration of the operation and which may introduce significant error. In contrast, potential distribution maps can be constructed in less than 3 minutes and can be viewed as a movie of developing and receding potentials. In 4 patients undergoing operation for VT, endocardial mapping was performed using form-fitting electrodes containing 160 points. A computerized mapping system, capable of simultaneously recording 256 channels of data, was used to analyze data and to display potential distribution maps sequentially at 1-millisecond intervals as a color movie. A total of eight morphologies of sustained VT were mapped. The mean VT cycle length was 340 +/- 40 milliseconds (range, 274 to 394 milliseconds). In 3 patients with ischemic heart disease, four VT morphologies originated from the subendocardium. All were successfully ablated with cryoablation alone or in conjunction with aneurysmectomy and endocardial resection. A fourth patient with VT secondary to cardiomyopathy had multiple morphologies and received an implantable cardioverter defibrillator. Potential distribution maps correlated well with the concomitant activation time maps. Thus, potential distribution mapping provides a rapid and accurate means of identifying the site of origin of VT facilitating intraoperative mapping in patients undergoing surgical ablation.

The long-term outcome of visually directed subendocardial resection in patients without inducible or mappable ventricular tachycardia at the time of surgery

INTRODUCTION

In prior studies, 20% to 40% of patients undergoing subendocardial resection (SER) for ventricular tachycardia (VT) could not be mapped intraoperatively because the VT was either noninducible or nonmappable following the ventriculotomy. The optimal surgical approach to such patients is not known.

METHODS AND RESULTS

In this study, we retrospectively compared the long-term survival and functional outcome of 29 patients with VT and prior myocardial infarction who were either noninducible or nonmappable intraoperatively and underwent a visually directed extended SER. These results were then compared to 85 patients who had inducible VT intraoperatively and underwent a map-guided sequential SER. The two patient groups had different clinical characteristics. The visually directed cohort was more likely to be male, experienced fewer VT episodes before surgery, and underwent fewer antiarrhythmic drug trials prior to resection. In addition, the visually directed group had slower VT induced at a preoperative electrophysiologic study and was less likely to present to the operating room in shock or incessant VT than the map-guided group. The postoperative VT clinical recurrence or inducibility rate was 14% in both the visually directed and map-guided groups. The long-term actuarial survival at 1, 3, and 5 years was 93%, 86%, and 75%, respectively, in the visually directed group, compared to 77%, 58%, and 58%, respectively, in the map-guided group (P = 0.06). There were no documented nonfatal recurrences of VT in either group. At 24 months following surgery, 77% of patients who had a visually directed SER were in New York Heart Association Functional Class I or II, compared to 46% of patients who underwent a map-guided SER (P < 0.05).

CONCLUSION

In patients with VT and prior myocardial infarction, the inability to induce or map the VT in the operating room does not preclude a favorable long-term outcome if a visually directed extended SER technique is used.

Surgical therapy for drug-refractory ventricular tachycardia: role of additional aneurysmectomy or bypass grafting

To assess whether additional aneurysmectomy and/or bypass grafting influence prognosis we studied 97 patients with recurrent sustained monomorphic ventricular tachycardia after an old myocardial infarction. All patients underwent subendocardial resection due to drug-refractory ventricular tachycardia. There were 41 patients who had resection alone, 27 patients had resection and aneurysmectomy, 13 patients had resection and bypass grafting and the remaining 16 patients had resection with both, aneurysmectomy and bypass grafting. During the mean follow-up of 40 +/- 27 months 29 patients died (30%) (total mortality), 7 patients suddenly (7%) and 20 patients from cardiac causes (20%). There were no significant differences in total mortality between patients with resection alone (32%), patients with resection and aneurysmectomy (22%), patients with resection and bypass grafting (31%) and patients who had resection, aneurysmectomy and bypass grafting (38%). In addition, no significant differences were observed in the incidence of sudden death and nonfatal recurrences between patients with resection alone: sudden death 12%, recurrences 7%; patients with resection and aneurysmectomy: sudden death 0%, recurrences 19%; patients with resection and bypass grafting: sudden death 0%, recurrences 8%; and patients with resection, aneurysmectomy and bypass grafting: sudden death 13%, recurrences 0%. Postoperatively, left ventricular function improved in 56% of patients who had resection and aneurysmectomy compared to 17% of patients with resection alone, 31% of patients with resection and bypass grafting and 19% of patients who had resection, aneurysmectomy and bypass grafting. There is a low risk of sudden death and nonfatal recurrences after subendocardial resection. An influence of additional surgical approaches (aneurysmectomy or bypass grafting) on prognosis is not visible.

Experience with a new implantable pacer-, cardioverter-defibrillator for the therapy of recurrent sustained ventricular tachyarrhythmias: a step toward a universal ventricular tachyarrhythmia control device

Ten consecutive patients (mean age 57.9 +/- 7.6 years) were treated with an investigational tachyarrhythmia control device, the implantable Medtronic Pacer-, Cardioverter-, Defibrillator model 7216A or 7217B. All patients had coronary artery disease with old myocardial infarctions and presented hemodynamically significant sustained ventricular tachyarrhythmias not suppressed by antiarrhythmic drug therapy and unrelated to acute myocardial infarction. In two patients a nonthoracotomy lead system was implanted. Lowest effective defibrillation energy ranged from 5 to 18 joules (mean 12.2 +/- 4 joules) for the epicardial bielectrode systems and were 15 and 18 joules for the nonthoracotomy lead system implants. The postoperative periods were unremarkable. Follow-up ranged from 7 to 19 months (mean 13.8 +/- 4.5 months). Spontaneous tachyarrhythmia episodes were detected and treated by the device in six patients, five of them received staged therapies. No deaths occurred and no hospital admissions were necessary for device related or ventricular tachyarrhythmia related complications. In conclusion, this integrated device represents a major step toward the development of a universal ventricular arrhythmia control device.

The role of cryosurgery in the management of cardiac arrhythmias

In the late 1970s, cryoablation of the AV node, accessory pathways, and ventricular tachycardia was first demonstrated and the technique was thought likely to assume an increasing importance in the surgical management of cardiac arrhythmias. However, more than 10 years later, cryotherapy is relatively sparingly used in these situations, and is at best an adjunctive means of therapy. The principal reason for this may lie in what was thought to be its major advantage: the fact that it is a highly selective, precise means of ablating myocardial tissue. Whereas electrophysiological mapping of tachycardia is able to identify apparently localized areas of arrhythmia substrate, relatively wide surgical destruction of myocardial tissue is frequently required to ensure successful tachycardia abolition: discrete, precise means of ablation are at a disadvantage. The future role for cryosurgery would seem to lie in those areas of arrhythmia management where selective ablation of substrate is essential. The ability of cryosurgery to modify (rather than simply ablate) AV nodal physiology in patients with AV nodal re-entrant tachycardia is such that it is likely to rival the recently reported catheter techniques for modification of the AV node.

Surgery for ventricular arrhythmia

Years of frustration of cardiac surgeons attempting to control intractable ventricular arrhythmia finally ended when the team of Harken, Josephson, and Horowitz performed electrophysiologically directed left ventricular endocardial resection and reported their early results 10 years ago. The scientific background for this breakthrough is reviewed and some subsequent modifications of their procedure are described. The current status of arrhythmia surgery since the advent of the automatic internal cardioverter-defibrillator is described: the two methodologies are complementary, not competitive.

Overview of the clinical electrophysiology study

Clinical electrophysiology testing is now a standard, useful technique for assessing patients with bradyarrhythmias or tachyarrhythmias. The technique requires specialized training and equipment. The recording equipment and program stimulator have evolved to sophisticated devices allowing accurate reproduction of intracardiac electrograms and timing of programmed extrastimuli. Electrophysiologic studies are useful for determining the mechanisms of a tachycardia or bradycardia and identifying the most appropriate therapy, whether it be pacing, antiarrhythmic medications, transvenous ablation, or electrosurgery.

Surgical therapy for drug-refractory ventricular tachycardia: results with mapping-guided subendocardial resection

Surgical therapy with mapping-guided subendocardial resection was used in 30 patients with drug-refractory ventricular tachycardia. Results of preoperative, intraoperative and postoperative electrophysiologic evaluation and long-term clinical follow-up are reported. Left ventricular aneurysm was located in the inferior wall in 8 patients and in the anterior wall in 22. Left ventricular mapping was performed in 15 patients preoperatively and in all 30 patients intraoperatively. Subendocardial resection was supplemented with cryoablation in 26 patients and with laser photocoagulation in 4. Coronary bypass surgery was performed in 27 patients. The surgical mortality rate was 10%; the three deaths were due to cardiogenic shock, pneumonia and sepsis, respectively. At postoperative electrophysiologic study, ventricular tachycardia was inducible in 8 (30%) of 27 patients. Previously ineffective antiarrhythmic drugs were effective in preventing the induction of ventricular tachycardia in four of these eight patients. Two of the remaining four patients received an automatic implantable cardioverterdefibrillator; the other two were treated with amiodarone. At a mean follow-up period of 18 +/- 17 months (range 1 to 52), there has been one sudden death and one nonfatal recurrence of ventricular tachycardia in the 18 patients without inducible arrhythmias postoperatively. Among the eight patients with inducible ventricular tachycardia after subendocardial resection, there has been one nonfatal ventricular tachycardia recurrence. Thus, among the 27 patients surviving surgery, 17 (63%) were cured with surgery alone, and another 7 (26%) had their ventricular tachycardia controlled with drugs (n = 5) or the defibrillator (n = 2). Inability to completely map the tachycardia, a clinical history of cardiac arrest requiring resuscitation and the presence of myocardial infarction within 2 months predicted postoperative arrhythmia inducibility and recurrence.

Prophylactic automatic implantable cardioverter-defibrillator patches in patients at high risk for postoperative ventricular tachyarrhythmias

The strategy of placing prophylactic patches for the automatic implantable cardioverter-defibrillator (AICD) without the AICD was employed in 34 patients with coronary artery disease at risk for postoperative ventricular tachycardia undergoing coronary bypass graft surgery (12 patients) or subendocardial resection (22 patients). Patients were selected on the basis of the presence of preoperative sustained ventricular tachycardia (25 patients) or ventricular fibrillation (9 patients) and absence of control of the arrhythmia with 3.6 +/- 1.3 antiarrhythmic drugs by programmed stimulation. Patients having subendocardial resection were also selected on the basis of multiple configurations of ventricular tachycardia, inability to map the tachycardia or posterior wall aneurysm. The surgical mortality rate was 12%, with two deaths after coronary bypass graft surgery and two deaths after subendocardial resection. The AICD patches were removed in 1 of the 34 patients a few hours after surgery because of left atrial laceration and bleeding. Among 10 patients surviving coronary bypass surgery alone, ventricular arrhythmia was not inducible in 6 and in 4 it remained inducible postoperatively. One of the four patients with inducible arrhythmia had the AICD implanted with use of local anesthesia; the other three were treated with drugs. Among 20 patients surviving subendocardial resection, ventricular arrhythmia was noninducible in 15 and remained inducible in 5. Three of these five patients had an AICD implanted; the other two were treated with drugs. At 12 +/- 7 month follow-up, there were no late deaths.(ABSTRACT TRUNCATED AT 250 WORDS)

Left ventricular aneurysm: a review

The vast majority of left ventricular aneurysms (LVA) are secondary to coronary artery disease. The natural history of LVA is now better understood. The increasing use of noninvasive techniques has allowed earlier recognition and better appreciation of LVA genesis and pathophysiology. Improvements in surgical anesthesia and techniques have resulted in more successful LVA surgery. This article reviews the pathogenesis, natural history, and complications of LVA. Surgical indications and available treatment options in the management of patients with LVA and severe symptoms are presented. Left ventricular pseudoaneurysm (false aneurysm) will also be discussed.

Treatment of life-threatening ventricular arrhythmias with nonguided surgery supported by electrophysiologic testing and drug therapy

Forty-six patients who had coronary artery disease, left ventricular aneurysm and life-threatening ventricular tachyarrhythmia underwent surgical treatment to eliminate or facilitate control of the arrhythmia. Surgery was performed without the assistance of intraoperative mapping techniques. Forty-three patients underwent preoperative or postoperative electrophysiologic testing, or both, and antiarrhythmic therapy was added, when indicated, postoperatively. The patients had a mean age of 63 years, a mean preoperative left ventricular ejection fraction of 27 +/- 9% and a mean preoperative left ventricular end-diastolic pressure of 23 +/- 9 mm Hg. Twenty-one patients (46%) underwent surgical treatment within 2 months of their last myocardial infarction. The overall operative mortality rate was 6.5% (three patients). Eighteen of the 43 operative survivors were discharged from the hospital on no antiarrhythmic therapy, whereas 25 received additional antiarrhythmic treatment. During a mean follow-up period of 36 months (range 2 to 88), there were 13 deaths; eight patients died suddenly, three died of congestive heart failure, one of myocardial reinfarction and one from a noncardiac cause. The overall cumulative cardiac mortality rate at 1, 2 and 3 years was 16, 22 and 35%, respectively, whereas the sudden cardiac death rate was 5, 12 and 20%, respectively. This experience suggests that high risk patients who undergo nonguided surgery for life-threatening ventricular arrhythmia and left ventricular aneurysm have a relatively low surgical mortality and a better long-term survival than previously reported. However, if utilized, such an approach must be systematically supported by perioperative electrophysiologic testing to determine the need for supplemental antiarrhythmic therapy.

Surgery of ventricular tachycardia and ventricular fibrillation in patients with coronary artery disease and LV-aneurysms

In 26 patients with left ventricular aneurysm and ventricular tachycardia and/or ventricular fibrillation following myocardial infarction, coronary angiography, left ventriculography and electrophysiologic examination were performed preoperatively. Surgery in all cases consisted of aneurysmectomy and mapping-guided endocardial resection of the area found to be the arrhythmogenic center. Four patients died peroperatively or during the postoperative hospital stay. The 22 survivors were followed up for 3-48 (mean 22) months postoperatively. There were no late deaths. Repeated electrophysiologic studies were performed in 18 of the survivors. Freedom from ventricular tachycardia and fibrillation was achieved in 21 patients, 17 after surgery alone and four after combined surgical and medical treatment. The remaining patient still has ventricular tachycardia despite combined treatment.

Encircling endocardial ventriculotomy for malignant ventricular arrhythmias. Effect on cardiac performance

Cardiac performance and hemodynamics were studied with radionuclide ventriculography in 19 survivors of aneurysmectomy and encircling endocardial ventriculotomy for recurrent, sustained ventricular arrhythmia (group I). To characterize the effect of the ventriculotomy on cardiac function, comparisons were made with a similar group of patients who underwent aneurysm surgery for angina pectoris and/or congestive heart failure (group II). Functional classification revealed no difference between the groups and they achieved the same level of exercise after surgery. No intergroup difference was found postoperatively with respect to right or left ventricular ejection fraction, regional ejection fractions, peak ejection rate, cardiac index or stroke volume. Peak filling rate was also similar, as were cardiac volumes. Exercise did not change any parameter of this intergroup similarity. The authors conclude that most patients with moderately impaired left ventricular function who undergo left ventricular aneurysmectomy with encircling endocardial ventriculotomy do not differ in postoperative hemodynamics and systolic or diastolic function from those treated with simple aneurysmectomy.

Prognosis following sustained ventricular tachycardia occurring early after myocardial infarction

Eighty-seven patients with sustained ventricular tachycardia (VT) between 3 and 90 days after acute myocardial infarction (AMI) were evaluated to define factors associated with a high risk of arrhythmia recurrence or death. Most patients had poor left ventricular function (mean ejection fraction 29 +/- 12%), multivessel coronary artery disease (71%) and inducible sustained VT with programmed stimulation (87%). During a mean follow-up of 26 months, 36 patients (41%) died and 21 patients had arrhythmia recurrence (with 19 sudden deaths). Factors independently associated with mortality included: (1) treatment before 1981 (p less than 0.01); (2) anterior AMI (p less than 0.05); (3) short time from AMI to first episode of VT (p less than 0.06); and (4) multivessel coronary artery disease (p less than 0.07). Factors independently associated with arrhythmia recurrence were: (1) medical treatment (as opposed to surgical) (p less than 0.01); (2) greater than or equal to 3 episodes of spontaneous VT (p = 0.01); (3) multivessel coronary disease (p less than 0.05); and (4) anterior AMI (p less than 0.07). Medically and surgically treated patients did not differ significantly in overall survival (49 vs 61%, respectively), although short-term (6 month) surgical survival improved from 31% during the first half of the study to 96% in the latter half (p less than 0.01). For patients with sustained VT early after AMI the risk of death and arrhythmia recurrence can be assessed based on clinical and angiographic characteristics; in addition, surgical treatment is associated with a lower incidence of arrhythmia recurrence than medical treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Left ventricular aneurysm repair with myocardial revascularization: an analysis of 246 consecutive patients over 15 years

From 1970 to 1985, 246 consecutive patients with left ventricular (LV) aneurysm underwent repair and concomitant myocardial revascularization at Ochsner Foundation Hospital. The overall incidence of perioperative death was 7.3%. Although the deaths were mainly cardiac related (10/18) with congestive heart failure (CHF) as the leading cause (6/10), 8 deaths were of noncardiac origin. Perioperative mortality increased significantly in patients with mitral regurgitation (MR) (22%; p = 0.0008); perioperative mortality for patients without MR was 4.8%. The overall 5-year survival was 69%. Late deaths were caused most commonly by myocardial infarction (20/32) with only 7 due to CHF. Predictors of long-term survival were related to LV function preoperatively: absence of CHF (p = 0.001); LV end-diastolic pressure less than or equal to 20 mm Hg (p = 0.03); and ejection fraction greater than or equal to 35% (p = 0.02). Factors that did not significantly affect long-term survival were type of aneurysm repair (resection or plication), morphology of left anterior descending coronary artery (occlusion or stenosis), and size of the aneurysm.

Surgical treatment of arrhythmias

Surgical treatment of arrhythmias is often more expeditious and more cost-effective in the long run than pharmacologic therapy. In the past, surgical treatment of arrhythmias has been reserved for patients with disabling paroxysmal or incessant tachycardia refractory to medical management, severe life-threatening arrhythmia or aborted episodes of sudden death. However, tachyarrhythmias that are refractory to pharmacologic therapy because of drug inefficacy, noncompliance or limiting side effects are not uncommon. Although nonpharmacologic treatment of arrhythmias carries with it a one-time period of higher risk (i.e., when the patient undergoes surgery), it is curative and often preferable to the uncertainty and possibly higher cumulative risk associated with medical management.

Excisional surgery for patients with ventricular tachyarrhythmias

Thirty-eight patients with drug refractory ventricular tachycardia have been operated on since 1980. An attempt at preoperative localization of the site of arrhythmia was made in those patients who did not have severe ischemia or multifocal tachycardia. Operation consisted of intraoperative mapping, when feasible, subendocardial resection and cryolesions placed when sites of interest could not be resected. Patients averaged 56 +/- 44 years of age and 25 had associated coronary bypass. The operative mortality was 5/38 (13%) and two deaths were related to recurrent arrhythmia. Of 33 survivors, 21 (64%) were cured of their arrhythmia and an additional nine patients who had been drug refractory were controlled with medication alone. The best results were found in patients with anteroapical scar and unifocal tachycardia. Thus, direct operation for drug refractory ventricular tachycardia can be performed at a reasonable risk and with a high likelihood of successful arrhythmia control.

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.

Perioperative and long-term results after electrophysiologically directed ventricular surgery for recurrent ventricular tachycardia

Thirty-six patients underwent ventricular aneurysmectomy and electrophysiologically directed endocardial resection for treatment of recurrent ventricular tachycardia refractory to antiarrhythmic drug therapy. The surgical mortality rate was 17% and all 30 patients discharged from the hospital were alive at the end of the follow-up period (range 6 to 54 months), yielding a cumulative projected survival rate of 83% by actuarial analysis. Poor systolic function of the nonaneurysmal ventricular segments was the strongest and the only independent predictor of operative mortality among the clinical, hemodynamic, angiographic and electrophysiologic variables analyzed by stepwise logistic regression. Ventricular tachycardia recurred early in four of the six patients in whom the endocardial resection was limited to a small area for technical reasons. Twelve patients, including 10 with sustained ventricular tachycardia still inducible by postsurgical programmed electrical stimulation, were discharged receiving antiarrhythmic drugs that had been tried unsuccessfully before surgery. During a mean follow-up period of 25 +/- 15 months, nonfatal sustained ventricular tachycardia recurred in two patients after discharge. Inadequate endocardial resection was a significant predictor of arrhythmia recurrence.