Isaac Gielchinsky

Intraoperative mapping-guided argon laser ablation of malignant ventricular tachycardia.

Intraoperative mapping-guided laser ablation of arrhythmogenic myocardium was performed in 5 patients with refractory sustained ventricular tachycardia (VT). Using a 15-W argon laser coupled to a 300-mu optical fiber, a bloodless laser ventriculotomy was successfully performed in 4 patients with VT. Visually- and mapping-guided endocardial ablation of 7 VT morphologic patterns was performed. Five of the 7 sites of VT origin were unresectable using standard resection techniques. Postoperatively, spontaneous and inducible VT was suppressed in all patients (without antiarrhythmic drugs in 4 patients and with a previously ineffective drug 1 patient). Mean pulmonary capillary wedge pressure, cardiac index and left ventricular ejection fraction were unchanged (p greater than 0.2) from preoperative values. Mean maximal creatinine kinase-MB isoenzyme concentration was 139 +/- 75 IU. All patients were New York Heart Association functional class II at discharge. During follow-up, no spontaneous arrhythmia has recurred in any patient. Thus, intraoperative argon laser ablation is effective for VT ablation alone or in conjunction with standard surgical resection techniques.

Argon laser ablation of malignant ventricular tachycardia associated with coronary artery disease

The long-term clinical efficacy and safety of intraoperative mapping-guided argon laser ablation alone or in conjunction with standard surgical methods were assessed in 20 consecutive patients with refractory sustained ventricular tachycardia (VT) or ventricular fibrillation. A 15-W argon ion gas laser was used and pulsed laser energy was delivered through a fiberoptic catheter delivery system. Pre- and intraoperative mapping was used to localize the arrhythmogenic tissue. Postoperative clinical, ambulatory electrocardiographic and electrophysiologic evaluations were performed before discharge and at 1 year of follow-up. Thirty-eight VT morphologies were mapped and ablated with laser energy alone (82%), combined laser ablation and mechanical resection (13%) or mechanical resection alone (5%). Concomitant coronary artery bypass surgery was performed in 15 patients and in 1 patient it was performed with mitral value replacement. Postoperative 30-day mortality was 5%. One patient (5%) required postoperative antiarrhythmic drug therapy, and all survivors had suppression of inducible sustained VT at discharge. Mean left ventricular ejection fraction increased from 34 +/- 12% preoperatively to 41 +/- 13% postoperatively (p = 0.001). Efficacy rates for ablation of VT sites associated with anterior myocardial infarction and inferior or posterior myocardial infarction were comparable (100 vs 96%, respectively, p greater than 0.2). At 1-year follow-up no sudden deaths had occurred and total survival rate was 90%. Intraoperative pulsed argon laser ablation alone or in conjunction with standard surgical techniques improves the efficacy of surgical ablation procedures for VT or ventricular fibrillation and reduces the need for additional postoperative antiarrhythmic drug or device therapy.

Long-Term Efficacy of Subendocardial Resection in Refractory Ventricular Tachycardia: Relationship to Site of Arrhythmia Origin

Subendocardial resection is performed in patients with ventricular tachycardia (VT), but its efficacy as related to the site of origin of VT is problematic. We analyzed the efficacy of subendocardial resection in 24 patients with coronary artery disease and VT. All patients underwent preoperative and intraoperative mapping before subendocardial resection. Postoperative electrophysiologic studies were performed in the drug-free state 7 to 14 days after subendocardial resection. Group 1 (n = 14) had anterior, septal, or lateral sites of origin, and Group 2 (n = 10) had inferior or posterior sites of origin. Localization of presystolic electrical activity during VT by preoperative and intraoperative mapping was comparable in both groups (100%). Resectability of the site of origin was higher in Group 1. Induction of VT during a postoperative electrophysiological study was higher in Group 2. Perioperative mortality was comparable. Postoperative antiarrhythmic therapy was instituted more frequently in Group 2. Actuarial survival analysis showed improved patient survival at one year after subendocardial resection for both groups. The efficacy of subendocardial resection is related to site of origin of VT: Subendocardial resection is less efficacious in VT with inferior or posterior sites of origin because of nonresectability of the arrhythmogenic area.

Argon laser ablation or modification of the atrioventricular conduction system in refractory supraventricular tachycardia

Management of drug-refractory supraventricular tachycardia has been greatly facilitated by several nonpharmacologic therapeutic options. These options include catheter or surgical ablation of the arrhythmogenic substrate or the use of antitachycardia pacemakers. Catheter ablation is performed for interruption or modification of normal or abnormal atrioventricular (AV) conduction using direct current shocks or radiofrequency energy.1 Intraoperative ablation of these conduction pathways is now only performed in the following cases: in symptomatic patients who have either failed catheter ablation; concomitantly with cardiac surgery for another indication; or in place of catheter ablation in specific conditions, for example, preexcitation syndromes. Implantation of antitachycardia devices is usually restricted to a few highly selected patients. Experimental studies have suggested that argon laser ablation of the specialized AV conduction system or accessory pathways is feasible.2,3 Since 1986, we have used catheter delivery of argon laser energy for intraoperative ablation of malignant supraventricular and ventricular tachycardia.4–6 We have previously reported its use in supraventricular tachycardia associated with the Wolff-Parkinson-White syndrome.5,7 In this study, we report our initial clinical experience with normothermic argon laser catheter ablation of the specialized AV conduction system and examine its clinical electrophysiologic effects.

Surgery of the Ebstein's anomaly: early and late outcomes.

Abstract  Background: Ebsteins anomaly of the tricuspid valve is a complex malformation. Several operations have been undertaken with varying results. The severity of the morphology of the lesion and ventricular function determine the spectrum of surgical techniques that are employed with varying results. Methods: Between 1980 and 2005, 45 patients with Ebsteins anomaly underwent surgical repair. Age at operation ranged from 3 to 26 years (median 15.5, mean 18.0 years). In 41 patients (91%), tricuspid valvuloplasty was done. The other four patients had valve replacement with bio‐prosthesis. Eight patients required ventricular unloading by creating bidirectional Glenn procedure in addition to a valve repair. Seven needed re‐operations: one repeat valve repair, two valve replacements and three takedown of Glen shunt, and one Fontan operation. Results: In‐hospital deaths occurred in two patients (4.4%) and late mortality in four patients (9%). 95% of 39 survivors were followed for 5 months to 19.5 years (median follow‐up, 5.0 years; mean follow‐up, 6.9 years). The actuarial survival rate (Kaplan‐Meier) was 96.5%± 2.4% at 1 year, 84.4%± 3.5% at 10 years and 83.3%± 5.6% at 19 years. At follow‐up 90% were in functional class I or II with substantial improvement compared with their preoperative status. Doppler echocardiographic studies demonstrated good tricuspid valve function in most patients. Conclusions: Valve repair or replacement tailored to the anatomical substrate of the anomaly yielded good long‐term results with substantial improvement in functional status. Bidirectional Glenn anastomosis combined with a valve repair improved ventricular function and improved both the early and late outcomes. (J Card Surg 2011;26:227‐233)

Treatment outcomes in 23 thoracic primitive neuroectodermal tumours: a retrospective study

OBJECTIVES Thoracic primitive neuroectodermal tumour is an aggressive malignancy with poor survival despite multimodality treatment regimens. Early diagnosis of the tumour by histological, immunohistochemical, ultrastructural and cytogenetic techniques and early total surgical resection of the tumour with intensive chemoradiation may improve outcomes. METHODS Over 30 years, 23 patients (median age 29.5) with primitive neuroectodermal tumours (15 chest wall, 4 lung, 3 costovertebral sulcus and 1 anterior mediastinum) were diagnosed by transthoracic needle biopsy (43%) or excisional biopsy (57%). Treatment of a localized disease (Stage I and II) in 19 patients included surgery (wide excision of chest lesions in 11, 4 lung resections, excision of 3 costovertebral sulcus and 1 anterior mediastinal tumours, and resection of adjacent tissues involved by tumour en bloc) with adjuvant chemoradiation. Four metastatic chest wall tumours (Stage III) had chemotherapy and radiation alone. RESULTS Tumour recurred in 5 (2 chest wall, 2 costovertebral sulcus and 1 lung) requiring further chemotherapy, radiation and completion pneumonectomy for a lung recurrence. The incidence of recurrent tumour in 7 years for Stage I was 21 vs 40% (P=0.4) for Stage II lesions and 16% after the neoadjuvant chemotherapy vs 30% (P=0.4) after adjuvant chemoradiation. Four with recurrence, except one with a chest recurrence, succumbed to second relapse (78-96 months). All four Stage III chest tumours succumbed to advanced disease (30 months). The Kaplan-Meier disease-free survival of the overall group (23 patients) was 82±2% at 5 years and 64±3% at 10 years. The 10-year disease-free survival of 19 patients with localized tumours was 76%, but was high at 90% for chest wall tumours and low 33% for costovertebral sulcus tumours (P≤0.01). The 10-year disease-free survival was 86% for Stage I vs 60% (P=0.02) for Stage II tumours; and 83% for neoadjuvant vs 76% (P=0.06) for adjuvant chemotherapy and radiation. CONCLUSIONS The primitive neuroectodermal tumours are aggressive neoplasms with poor prognosis. Early diagnosis and total surgical excision of localized tumours with neoadjuvant or adjuvant chemotherapy and radiation improved disease-free survival.

Results of coronary bypass and valve operations for mitral valve regurgitation.

Combined coronary bypass grafting and valve procedures for mitral valve regurgitation result in poor outcomes, but the impact of the etiology of valve regurgitation on operative and long-term outcomes is not well defined. A retrospective analysis of 468 patients who had combined coronary bypass grafting and valve operations for mitral regurgitation showed that 78% had valve repairs and 22% had replacements for ischemic (45%) or degenerative (55%) disease. Predictors of operative mortality were ischemic mitral regurgitation, failure to use the internal mammary artery for grafting, severe coronary disease, acute myocardial infarction, low ejection fraction, advanced heart failure, emergency operation, and mitral valve replacement. The 5-year survival rates for propensity-matched patients with ischemic or degenerative disease were similar (66%). Low ejection fraction (< 35%), advanced age (> 67 years), valve replacement surgery, residual mitral regurgitation, and severe coronary artery disease were predictors of poor long-term outcome. Although the operative outcomes of ischemic mitral regurgitation were poor compared to those of degenerative disease, the long-term survival was similar in both groups of propensity-matched patients. Left ventricular remodeling, an optimal valve procedure without residual mitral regurgitation, and left ventricular function are more important determinants of long-term outcome than the etiology of valve regurgitation.

Pulmonary Inactivation of Vasopressors Following Cardiac Operations

Vasoactive drugs were infused through catheters in the right atrium and then the left atrium of 34 patients who required either vasopressor or vasodilator support following cardiac operation to determine if the route of infusion affected the aortic blood concentration of these agents. Drugs were given through the right atrium for one hour and then the left atrium for an hour. Both central aortic and pulmonary arterial blood were assayed for drug concentrations, and hemodynamic measurements were made. Sixteen patients receiving dopamine hydrochloride through the left atrium had a 36 +/- 12% (+/- standard error of the mean) increase in aortic concentration of the drug (p less than 0.005) and a 37 +/- 14% increase in cardiac index (p less than 0.005) compared with administration through the right atrium. Seven patients receiving epinephrine showed a 59 +/- 21% increase in aortic concentration (p less than 0.05) and a 21 +/- 10% increase in cardiac index (p greater than 0.05, not significant). Eleven patients receiving sodium nitroprusside achieved a 99 +/- 25% increase in aortic concentration (p less than 0.005) and a 20 +/- 7% increase in cardiac index (p less than 0.05). In all instances, significantly higher central aortic blood concentrations were achieved during left atrial (LA) versus right atrial (RA) infusions. Changes in blood concentration of the drug between the pulmonary artery and the aorta during RA infusion suggest removal or inactivation of these drugs in the pulmonary vasculature.(ABSTRACT TRUNCATED AT 250 WORDS)