Surgical treatment of ventricular arrhythmias in coronary artery disease

Serious ventricular arrhythmias, a common complication of coronary artery disease, frequently respond to medical management. When pharmacologic and pacemaker therapy fail to control them, however, surgical therapy must be considered. In this review we assess the efficacy of surgical treatment of these arrhythmias. Coronary revascularization fails to reduce the frequency and complexity of ventricular ectopic activity and may exacerbate them. Recurrent ventricular fibrillation due to acute, reversible ischemic events may respond favorably to coronary revascularization. Recurrent ventricular fibrillation associated with recent myocardial infarction when unresponsive to medical therapy can be managed with coronary revascularization and infarctectomy with comparatively good results. Recurrent sustained ventricular tachycardia is not optimally treated with coronary artery bypass grafting and myocardial resection. Operations guided by activation mapping that isolate or destroy the site of origin of the ventricular tachycardia show promise.

The surgical treatment of ventricular tachycardia

Recurrent ventricular tachycardia is a well-recognized complication of ischemic heart disease. Coronary bypass operation with or without aneurysmectomy has been disappointing as therapy for these arrhythmias. With the advent of programmed electrical stimulation, it has become possible to distinguish automatic and reentrant ventricular tachyarrhythmias. The latter have recently proved amenable to operative intervention. This review examines the pathophysiology and diagnosis of ventricular tachycardia using programmed electrical stimulation. Surgical therapy with resection, revascularization, autonomic modulation, thermal ablation, cardiac pacing, reentrant circuit interruption, and endocardial excision is explored. Operation for cardiac arrhythmias is on a firm electrophysiological foundation. Surgical treatment of refractory ventricular tachyarrhythmias is now rational, recommended, and rewarding.

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

Nineteen patients undergoing a standard aneurysmectomy for recurrent ventricular tachycardia are compared with 30 patients unergoing electrophysiologically directed endocardial excision and aneurysmectomy. The electrophysiologically nondirected and electrophysiologically directed groups were aneurysmectomy. The electrophysiologically nondirected and electrophysiologically directed groups were similar for age (56.8 versus 57.5 years), interval after myocardial infarction (26.2 versus 28.3 months), preoperative episodes of ventricular tachycardia (13.2 versus 19.7), cardiac index (2.95 versus 2.79 L/min/m2), left ventricular end-diastolic pressure (15.5 versus 18.2 torr), and ejection fraction (34 versus 28%). Operative mortality rate in the nondirected group was 42%, with all but one of the deaths resulting from uncontrolled postoperative ventricular tachycardia. In the nondirected group 78.9% (15/19) of patients had recurrent ventricular tachycardia postoperatively. The operative mortality rate in the electrophysiologically directed group was 6.7% (2/30), and both patients died of left ventricular failure. Three patients (10%) have ventricular tachycardia inducible with programmed stimulation. We conclude that standard left ventricular aneurysmectomy is not an effective operation for recurrent sustained ventricular tachycardia. Conversely, electrophysiologically directed endocardial excision characteristically controls the arrhythmia at an acceptable surgical risk.

Endomyocardial fibrosis: report of 6 patients and review of the surgical literature

Six patients with endomyocardial fibrosis were treated by endocardium decortication and atrioventricular valve replacement. There were 5 female patients and 1 male patient ranging from 14 to 48 years old (mean, 30 years). Four patients had involvement of the right ventricle, 1 patient had involvement of the left ventricle, and 1 patient had biventricular disease. There was 1 operative death due to low cardiac output state (the patient with biventricular endomyocardial fibrosis), and there was 1 late noncardiac death. The surgical literature, which describes 19 previously reported cases, was reviewed. On the basis of the results of this series and those of the reported cases, it is concluded that surgical treatment of endomyocardial fibrosis is feasible and provides good clinical improvement.

Echocardiographic recognition of atrioventricular valve stenosis associated with endocardial cushion defect: pathologic and surgical correlates

The association of either mitral or tricuspid stenosis with endocardial cushion defects has been well recognized pathologically but is infrequenctly diagnosed clinically. M mode echocardiographic features such as markedly disproportionate ventricular size, abnormal mitral or tricuspid diastolic echoes or failure to define adequately an atrioventricular (A-V) valve are strongly suggestive of associated stenosis of that valve. In this study mitral stenosis in association with endocardial cushion defect was correctly diagnosed in four of five patients. In the fifth patient (the first seen) the condition was easily diagnosed retrospectively. Tricuspid stenosis was similarly diagnosed prospectively in three of four patients. Significant stenosis was not overlooked or misdiagnosed in any patient with an endocardial cushion defect. Significant stenosis of an A-V valve in association with endocardial cushion defect carries a high mortality. It is important to recognize the combined lesion clinically because infants with it are not suitable for total surgical correction. Palliative surgical procedures with aggressive medical therapy probably offer the infant the best chance of surviving until ventricular growth may render corrective surgery feasible.

Endocardial excision: a new surgical technique for the treatment of recurrent ventricular tachycardia

Twelve patients with medically refractory ventricular tachycardia secondary to ischemic heart disease underwent surgery for cure of their arrhythmia. Preoperatively, the tachycardia could be reproducibly initiated and terminated in each patient by programmed stimulation. In all instances, intraoperative mapping localized the tachycardia to the border of the aneurysm, a site not routinely resected during aneurysmectomy. In nine instances, the area of origin involved the septum. During bypass the tachycardia could still be induced after standard aneurysmectomy or ventriculotomy in 11 of 12 patients. On the basis of intraoperative mapping, resection of endocardium in the area of origin (25--40% the circumference of the aneurysmectomy) up to normal muscle was performed. In one patient without a discrete aneurysm, endocardial excision alone through a ventriculotomy was performed. There was one operative death due to cardiogenic shock (preoperative ejection fraction 5%) and one late death due to rupture of a mycotic aneurysm in the pulmonary artery. Before discharge, all patients underwent a repeat relectrophysiologic study off antiarrhythmic agents and in none could ventricular tachycardia be initiated. Hemodynamic and angiographic catheterization showed improved hemodynamics and ejection fractions in all. The 10 survivors remained free of sustained ventricular tachycardia for 9--20 months, with one late nonarrhythmic death.

Surgical endocardial resection for the treatment of malignant ventricular tachycardia

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Encircling endocardial ventriculotomy: a new surgical treatment for life-threatening ventricular tachycardias resistant to medical treatment following myocardial infarction

Ventricular tachycardias occurring after myocardial infarction (MI) and resistant to medical treatment were successfully treated in 5 patients by encircling endocardial ventriculotomy. All patients had a history of MI. The delay between MI and ventricular tachycardias ranged from 1 month to 8 years. A reentrant mechanism was demonstrated by laboratory studies. Under cardiopulmonary bypass, the left ventricle was entered through the thin fribrous scar. Encircling endocardial ventriculotomy was carried out from the inside of the ventricle, through the whole thickness of the normal myocardium, and along the border of the endocardial fibrosis, which delineated the area of diseased myocardium. The ventriculotomy was placed in the free wall or in the septum or in both of these locations. It was repaired and the left ventricle was closed. Drug therapy was discontinued after operation. No ventricular tachycardias recurred during a follow-up period of 6 to 24 months. The effectiveness of encircling endocardial ventriculotomy is explained by the exclusion of the entire diseased area, especially the border zone and the septum. This technique is useful in any location of MI.

Hypertrophic subaortic stenosis. Operative methods utilized to relieve left ventricular outflow obstruction

The methods currently used at the National Heart Institute in the operative treatment of patients with hypertrophic subaortic stenosis (IHSS) are described. Features of the operation that facilitate exposure of the septum and the criteria of an adequate myotomy are emphasized.

Recurrent sustained ventricular tachycardia. 2. Endocardial mapping

Endocardial ventricular mapping of 21 ventricular tachyardias (VT) in 17 patients was performed using electrode catheters. Activation at multiple left and right ventricular sites was utilized to determine the site of origin of the VT. Eleven VT had a left bundle branch block pattern (VT-LBBB) and 10 VT had right bundle branch block pattern (VT-RBBB). In all VT-RBBB the earliest site of activation was in the LV or septum. In VT-LBBB the earliest site was RV (4/11), LV (5/11) and septum (2/11). All ventricular tachycardias with QRS less than 140 msec arose in the septum. In patients with an aneurysm, the site of origin of ventricular tachycardia was always in the aneursm. All VT-LBBB arising from the left ventricle originated in an aneurysm involving the septum. QRS changes during ventricular tachycardia were associated with alterations in the patterm of ventricular activation without alteration of the site of origin. In three patients the site of origin predicted by endocardial ventricular mapping was confirmed intraoperatively by epi- and/or endocardial mapping. We conclude that endocardial ventricular mapping demonstrates the limitations of the surface electrocardiogram in localizing the site of origin of ventricular tachycardia. The method may provide important data upon which the surgical therapy of ventricular tachycardia is based.

[Fibroblastic constrictive endocarditis. Apropos of a form localized in the left ventricle]

The authors report a case of a localised form of this strange disorder which was confined to the left ventricle, and in which the diagnosis was tentative for a long time. In this case it was possible to carry out a removal of the fibrous plaque after opening the apex of the left ventricle, the mitral valve being preserved, as described by Dubost; the functional and haemodynamic results of this procedure were very satisfactory.

[Endocardial resection: surgical treatment of constrictive fibrous endocarditis]

A new operation, the resection of the endocardium, is proposed in the case of fibrous constrictive endocarditis. I performed this operation in 1971, for the first time, with good results. I operated on two other patients with success in 1973 and 1975. The results I have obtained indicate that this new technique is possibly the answer to a disease which otherwise ultimately results in death.

Modified technique for long-term endocardial pacemaking

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Electrical pacing of the heart with endocardial and implanted pacemakers: review of 60 cases

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