Mapping-guided focal cryoablation and endoaneurysmorrhaphy for a case of ischemic ventricular tachycardia with left ventricular aneurysm

A 74-year-old woman admitted with exertional dyspnea. Echocardiography revealed the giant left ventricular aneurysm. In the hospital course, she fell into sustained monomorphic ventricular tachycardia. Coronary angiogram showed complete obstruction of the LAD. Left ventricular ejection fraction was 20%. The origin of tachycardia seems to be at infero-apicallateral area of LV by electrophysiology study. Because of the failure of RF energy ablation, we planned mapping-guided cryoablation, CABG and endoaneurysmorrhaphy. To prevent air embolism and myocardial ischemic damage for long aortic cross clamp, intraoperative endocardial mapping was carried out on beating heart due to continuous normothermic coronary blood perfusion (300 ml/min) from the aortic root cannula under aortic clamping. Cold crystalloid cardioplegia changed into the root cannula after EPS, focal cryoablation (-100 degrees C) was performed 3 times on cardiac arrest. Sustained VT was not inducible in the following study. CABG and endoaneurysmorrhaphy was performed on repeated cardiac arrest during single aortic clamp. Postoperative course was uneventful, and she discharged 8 weeks after the operation.     

Sex difference and factors associated with outcome in patients with sustained ventricular arrhythmias

OBJECTIVE: To describe gender differences and factors of importance for outcome in patients referred for sustained ventricular arrhythmias. RESULTS: Two hundred and fifty three patients took part in the survey, 126 (20 women) had sustained monomorphic ventricular tachycardia (VT) and 127 (31 women) had polymorphic VT/ventricular fibrillation. Ischemic heart disease was less common in women than in men (47 vs. 80%). At discharge, an ICD implant was similarly common in women (33%) and men (29%). One hundred and twenty five (65%) men and 37 (79%) women were alive at follow-up, p =0.08 (median follow-up 53 months). Independent predictors of long-term mortality were: 1) PVT/VF as the presenting arrhythmia, 2) a low ejection fraction, 3) increased QRS duration and 4) diabetes mellitus. CONCLUSION: The lower proportion of women compared to men being referred for evaluation of sustained ventricular arrhythmias may contribute to the lower number of ICD implants in women. The long-term survival in women and men did not differ significantly.     

Risk factors for stroke after coronary artery bypass.

To determine the prevalence of stroke after coronary artery bypass grafting and to evaluate risk factors, we reviewed the records of 1000 patients undergoing coronary bypass within a 1-year time period. Demographic and perioperative data were evaluated by chi 2 analysis. A history of diabetes, evidence of mural thrombus, positive oculopneumoplethysmography findings, increased age, aortic calcification, and postoperative arrhythmias all correlated with increased risk of permanent neurologic deficit for the patient undergoing coronary bypass. Risk factors were analyzed with stepwise logistic regression. A history of diabetes, presence of mural thrombi, and aortic calcification carried a higher probability that the patient would have a permanent neurologic deficit.     

Transannular cryoablation of ventricular tachycardia. Surgical technique and results

Intraoperative mapping and cryoablation of ventricular tachycardia was achieved without ventriculotomy in seven patients, who are a subgroup of the 80 patients undergoing map-directed ablation of ventricular tachycardia over a 9-year period. There were four male and three female patients. Their mean age was 53.6 +/- 24.1 years. Coronary artery disease was present in five patients, and two patients had idiopathic ventricular tachycardia. The mean preoperative ejection fraction was 42.4% +/- 13.6%. The mean number of ventricular tachycardia morphologies was 1.7 (range 1 to 3). Epicardial mapping was obtained intraoperatively in all seven patients and endocardial data in five of seven patients (71.4%). There were no hospital deaths and no early or late spontaneous recurrence of clinical monomorphic ventricular tachycardia. Nonclinical monomorphic ventricular tachycardia was inducible in two patients postoperatively and both were treated with procainamide. Death occurred late after operation in two patients: One death was related to recurrent nonclinical VT at 8 months and one at 3 months was due to carcinoma of the stomach. These results suggest that the transannular approach is feasible in selected cases, especially when computerized mapping systems with endocardial balloon electrode arrays can be used.     

Surgery for ventricular tachycardia of left ventricular origin: risk factors for success and long-term outcome.

OBJECTIVES: To review 26 consecutive patients with sustained monomorphic ventricular tachycardia (VT) of left ventricular origin, who underwent direct VT surgery. METHODS: Economic factors precluded the use of an implantable cardioverter defibrillator (ICD) in the majority of these patients, and the indication for surgery in 81% of patients was for failed medical drug therapy and 27% of patients had frequent or incessant life-threatening VT. The principles of direct VT surgery included intraoperative mapping, extended endocardial resection, cryoablation, left ventricular aneurysm repair by left ventricular remodelling and endoaneurysmorrhaphy, as well as coronary artery bypass grafting. RESULTS: Two patients with non-ischaemic VT were significantly younger (37.7 +/- 19.4 years, P = 0.03), had lower preoperative New York Heart Association class (P = 0.03), and had better left ventricular ejection fractions of 59.5 +/- 2.1% (P = 0.001) than the 24 ischaemic patients. No operative mortality or recurrence of VT occurred in this group. Ischaemic VT patients had an operative mortality of 8.3%; risk factors were concomitant valve surgery (P = 0.02), and perioperative intra-aortic balloon pump (P = 0.02). Surgery improved the left ventricular ejection fraction from 28.4 +/- 9.8% to 43.2 +/- 8.2% (P = 0.0001). Freedom from recurrence or inducibility of VT in operative survivors was 78.8 +/- 9.6% at 10 years; risk factors were arrhythmic focus remote to the left ventricular aneurysm (P = 0.015), and simple cryoablation or endocardial resection alone and not in combination (P = 0.003). Survival was 54.1 +/- 11.6% and 43.3 +/- 13.4% at 5 and 10 years, respectively, and there were no arrhythmic or sudden cardiac deaths. Patients with immediately life-threatening VT unsuitable for ICD implantation requiring urgent or emergent VT surgery had a 10-year survival of 22.2 +/- 13.9% compared to the more elective surgical group with a rate of 73.3 +/- 13.9% (P = 0.08). CONCLUSIONS: Direct VT surgery should remain an objective for symptomatic drug refractory VT of left ventricular origin.     

Unexpected, sustained ventricular tachyarrhythmia after cardiac operations

Unexpected, sustained ventricular tachyarrhythmia after cardiac operations is differentiated from sustained ventricular tachycardia and ventricular fibrillation from known antecedent causes, such as recent or perioperative myocardial infarction, low cardiac output, preoperative ventricular arrhythmia, sympathomimetic drugs, drug toxicity, and metabolic abnormalities. Sixteen of 2364 patients (0.68%) who underwent heart operations met strict exclusion criteria for unexpected sustained ventricular tachyarrhythmia that occurred 1 hour to 12 days after operation. Recurrent ventricular tachyarrhythmias occurred in 12 patients; three died (21%), despite resuscitation from the initial episode. All patients had significant preoperative left ventricular dysfunction and 14 had ejection fractions below 30%. Fifteen of the 16 patients had monomorphic ventricular tachycardia at the initial episode. Empirically prescribed therapy was not effective in suppressing ventricular tachyarrhythmias inducible by programmed stimulation during postevent electrophysiologic studies in 10 of the 13 survivors. Inducibility was eventually prevented by drugs in nine patients, three patients received automatic implantable cardiac defibrillators, and one patient underwent successful catheter ablation of ventricular tachycardia. No patient died of recurrent ventricular tachyarrhythmias during the follow-up of 8 to 55 (mean 29) months after hospital discharge.     

Ventriculotomy and resection for left ventricular thrombus infection with Salmonella.

We report the case of a patient with a left ventricular thrombus infected by Salmonella. The diagnosis was suspected from a gallium scan demonstrating an intense activity in the lower left parasternal area. A transesophageal echocardiogram confirmed a calcified left ventricular aneurysm with a mural thrombus containing pus and heterogeneous material. The patient underwent a successful left ventricular aneurysmectomy, thrombectomy and endocardial resection under cardiopulmonary bypass which brought the infection under control.     

Late potentials, ventricular stimulation and ventricular tachycardia

Late potentials are depolarizations which arise from areas of delayed ventricular activation and may indicate a propensity for ventricular tachycardia. Sixty-four subjects were assessed by non-invasive measurement. Late potentials were not present in 20 subjects with normal hearts nor in 6 patients with cardiac disease but with no evidence of ventricular tachycardia (VT). Seventeen of 20 patients with recurrent sustained ventricular tachycardia (RSVT) and 2 of 10 patients with unsustained VT had late potentials. None of the 6 patients with automatic VT or the 2 patients with torsades de pointe had late potentials. In a subgroup of 28 symptomatic patients in whom programmed ventricular stimulation was performed, late potentials correlated with inducibility of sustained VT (P less than 0.05). Late potentials may therefore serve as a useful marker of RSVT and confirm a re-entrant mechanism of VT.     

Fatal cerebral embolus - a complication of left ventricular venting.

A 3-year-old child died following a routine tetralogy of Fallot repair. Death was caused by a cerebral embolus. Injury to the left ventricle during left ventricular venting resulted in an apical myocardial infarct. The embolic source was a mural thrombus covering the area of infarction. A technique is described whereby left ventricular venting can be avoided during open-heart surgery in small patients.     

Surgical treatment of tachyarrhythmias due to postinfarction left ventricular aneurysm with endoaneurysmorrhaphy and cryoablation.

OBJECTIVE: In this study, the efficacy of left ventricular (LV) endoaneurysmorrhaphy and cryoablation without intraoperative electrophysiologic mapping was evaluated in patients with postinfarction LV aneurysm and sustained ventricular tachycardia (VT). METHODS: A prospective study was performed on all patients operated with malignant VT in the presence of a resectable LV aneurysm between July 1990 and February 2001. RESULTS: The study included 31 patients, 20 men and 11 women, with a mean age of 65.5 years (47-84). Monomorphic, polymorphic VT or ventricular fibrillation was present in all patients prospectively, and VT was incessant in 11. Twenty-six patients had an anterior, four patients had an inferior and one patient a posterolateral myocardial wall infarction. All patients had a well-limited ventricular aneurysm. Ten patients had three, eight patients two and 13 patients had single vessel coronary artery disease. Mean preoperative ejection fraction was 34.8 +/- 14.5% (8-62) and mean end-diastolic volume index was 141.5 +/- 51.8 ml/m(2) (57-288). Six patients had mitral regurgitation grade III or IV. All patients underwent extensive cryoablation at the transition zone of scar and viable tissue and LV remodelling with prosthetic patch in 26 patients. Associated procedures were CABG in 19 patients (61%) and mitral valve reconstruction in six patients (19%). Postoperative electrophysiologic study (EPS) revealed freedom from VT induction in 25 patients and inducible VT in five patients. One patient had inducible polymorphic VT. Five patients received an implantable cardioverter defibrillator (ICD) and three patients had a permanent pacemaker implanted. After a mean follow-up of 30 +/- 27 months (6-132) there was one arrhythmia-related death. There was one early hospital readmission for clinical VT and no need for late ICD implantation. CONCLUSIONS: In patients suffering from ventricular arrhythmias in the presence of a complicated postinfarction LV aneurysm, combined 'blind' cryoablation and endoaneurysmorrhaphy offers excellent arrhythmia control and clinical and haemodynamic outcome.     

Surgical resection of a lupus-related left ventricular aneurysm in a patient with normal coronary arteries: case report

A 52-year-old woman with systemic lupus erythematosus (SLE) presented with shortness of breath. Echocardiography and cardiac catheterization demonstrated a discrete left ventricular aneurysm (LVA) with normal coronary arteries. Although her heart failure symptomatically improved with medical therapy, she suffered an embolic stroke from a thrombus within the LVA. She was treated with anticoagulation and rehabilitation for 6 weeks. Reevaluation with echocardiography demonstrated persistent depressed LV function and mural thrombus within the LVA. Surgical resection of the LVA was performed with evacuation of the thrombus and local repair of the LV.     

A successful cryosurgical treatment of malignant ventricular tachycardia following left ventricular aneurysm

A 61-year-old man underwent cryoablation in addition to aneurysmectomy and single aorto-coronary bypass for sustained ventricular tachycardia (VT) following left ventricular aneurysm. Two types of VT were observed clinically and electrophysiologically with programmed stimulation. During operation, VT was induced but could not be maintained on normothermic cardio-pulmonary bypass. Therefore cryoablation was performed on the two sites where the delayed potentials were recorded. Postoperatively recurrence of VT was never recognized clinically and electrophysiologically.     

Coronary artery bypass grafting in patients with ventricular fibrillation

The role of coronary artery revascularization in the management of survivors of cardiac arrest remains controversial. Patients with sustained monomorphic ventricular tachycardia rarely respond to revascularization, but the response of patients with ventricular fibrillation as their basic arrhythmia has not been characterized. Coronary artery bypass grafting was performed in 8 patients with a history of cardiac arrest known to be caused by ventricular fibrillation without preceding sustained monomorphic ventricular tachycardia. All patients had critical double-vessel or triple-vessel coronary artery disease, and 7 of 8 had wall motion abnormalities from a prior myocardial infarction. After successful operation, 5 patients had no spontaneous arrhythmias and no inducible arrhythmias at a postoperative electrophysiological study. Three patients, however, had spontaneous, recurrent episodes of ventricular fibrillation unassociated with recurrent ischemia. Clinical factors were not useful predictors of response. The effect of coronary artery revascularization in patients with ventricular fibrillation is unpredictable, and full postoperative electrophysiological evaluation is necessary to judge the success of the procedure.     

Surgical treatment of a case of arrhythmogenic right ventricular dysplasia with local myocardial resections

A 39-year-old man who was diagnosed as ARVD (arrhythmogenic right ventricular dysplasia) with nonischemic sustained ventricular tachycardia (VT) was successfully treated by surgical resection of two parts of the right ventricular free wall, one was the site of earliest excitation during induced VT and the other was an area where delayed potentials were detected during sinus rhythm. A surface mapping was made by means of a computer guided system. A preoperative study of endocardial mapping and a programmed electrical stimulation test were an useful adjunct for surgical management of ARVD. After surgery VT could not be induced by triple extrastimuli and up to now there has been no recurrence of VT more than 2 years after surgery without medication.     

Bioprosthetic mitral valve thrombosis less than one year after replacement and an ablative MAZE procedure: a case report

Occurrence of bioprosthetic valve thrombosis less than a year after replacement is very uncommon. Here, we describe a case of a 57 year old male, who presented 10 months after receiving a bioprosthetic mitral valve replacement with a two week history of dyspnea on exertion, worsening orthopnea and decreased exercise tolerance. Echocardiography revealed severe mitral regurgitation (MR), thrombosis of the posterior mitral leaflet, left atrial (LA) mural thrombus and a depressed left ventricular ejection fraction of twenty-five percent. Given severe clot burden and decompensated heart failure (New York Heart Association - NYHA class III) repeat sternotomy was done to replace the bioprosthetic mitral valve and remove LA mural thrombus. MR was resolved postoperatively. This brief report further reviews promoting factors, established guidelines and management strategies of bioprosthetic valve thrombosis.     

Salmonella infection of a ventricular aneurysm with mural thrombus

We describe a case of salmonella infection of a left ventricular aneurysm with a mural thrombus and review 12 cases described in the literature. This entity should be looked for in any patient with persistent or relapsing salmonella bacteremia in whom an intracardiac thrombus is demonstrated. Nuclear imaging may help in the diagnosis. A combined medical and surgical approach should be aggressively pursued because patients who do not undergo an aneurysmectomy are unlikely to survive.     

Impact of calcification and intraluminal thrombus on the computed wall stresses of abdominal aortic aneurysm

BACKGROUND: Increased biomechanical stresses within the abdominal aortic aneurysm (AAA) wall contribute to its rupture. Calcification and intraluminal thrombus can be commonly found in AAAs, but the relationship between calcification/intraluminal thrombus and AAA wall stress is not completely described. METHODS: Patient-specific three-dimensional AAA geometries were reconstructed from computed tomographic images of 20 patients. Structural analysis was performed to calculate the wall stresses of the 20 AAA models and their altered models when calcification or intraluminal thrombus was not considered. A nonlinear large-strain finite element method was used to compute the wall stress distribution. The relationships between wall stresses and volumes of calcification and intraluminal thrombus were sought. RESULTS: Maximum stress was not correlated with the percentage of calcification, and was negatively correlated with the percentage of intraluminal thrombus (r = -0.56; P = .011). Exclusion of calcification from analysis led to a significant decrease in maximum stress by a median of 14% (range, 2%-27%; P < .01). When intraluminal thrombus was eliminated, maximum stress increased significantly by a median of 24% (range, 5%-43%; P < .01). CONCLUSION: The presence of calcification increases AAA peak wall stress, suggesting that calcification decrease the biomechanical stability of AAA. In contrast, intraluminal thrombus reduces the maximum stress in AAA. Calcification and intraluminal thrombus should both be considered in the evaluation of wall stress for risk assessment of AAA rupture.     

Nonarrhythmogenicity of therapeutic cryothermic lesions of the myocardium

There is increasing interest in the application of surgical methods to the treatment of refractory ventricular tachyarrhythmias (VT). Cryothermic ablation is one of the more promising techniques. However, there is clinical concern that a cryothermic lesion may lead to later arrhythmias. Previous studies have shown that dogs with nonhomogeneous, transmural infarctions are susceptible to VT initiation using programmed electrical stimulation (PES). The purpose of this study was to compare the incidence of inducing VT in dogs with transepicardial cryothermic myocardial damage (Group A) versus dogs with nonhomogeneous transmural infarctions resulting from 2-hr occlusion of the left anterior descending coronary artery (LAD) and subsequent reperfusion (Group B). Twelve dogs in each group were studied 10-14 days later using PES with unipolar cathodal ventricular pacing and two ventricular extrastimuli. Initiation of VT was attempted from at least six normal intramyocardial sites in each dog along the distribution of the LAD and in close proximity (less than or equal to 1 cm) to areas of chronically cryoablated damaged tissue. All dogs survived the initial procedure. VT was not inducible in any dog in Group A. Histological as well as electrophysiological evaluation, including determination of regional excitability thresholds and refractory periods employing strength-interval curves, revealed that all of the Group A dogs had homogeneous transmural infarcts with variable subendocardial sparing. In conclusion (1) cryothermal injury produces homogeneous damage; and (2) the lesion produced is not arrhythmogenic at 7-14 days.     

Position dependent ventricular tachycardia in two children with peripherally inserted central catheters (PICCs)

We report two cases of ventricular tachycardia (VT) in children following the insertion of peripherally inserted central catheters (PICCs). These children had additional procedures requiring turning into the left lateral position after PICC insertion. In both cases sustained VT occurred after turning and flexion of the arm with the PICC. VT was terminated in both cases by withdrawing the catheter.     

Results of electrophysiologically guided operations for drug-resistant recurrent ventricular tachycardia and ventricular fibrillation due to coronary artery disease

Over a 39 month period, 143 patients with coronary artery disease had programmed stimulation (PES) for recurrent ventricular tachycardia (VT) or ventricular fibrillation (VF). Twenty-two patients underwent operations. Ages ranged from 40 to 71 years; 20 of the 22 were men. All patients had coronary artery disease and 11 had left ventricular aneurysms. The mean ejection fraction was 31% (16% to 50%). Eighteen of the 22 patients underwent operations for drug-resistant ventricular arrhythmias (more than six different drugs plus drug combinations tested per patient). Nineteen patients had intraoperative mapping, endocardial resection, and/or an encircling endocardial ventriculotomy. Three patients with ischemia-related VT had coronary artery bypass (CABG) alone. The 30 day operative mortality was 14%. Thirteen of 19 (68%) operative survivors were effectively controlled with operation alone or a combination of operation and previously ineffective drug therapy. Of the six patients whose VT was inducible postoperatively, three have experienced episodes of sustained VT and one patient died suddenly. Three of these patients have the automatic implantable defibrillator. Operation guided by endocardial mapping is effective alone or in combination with drugs in this select group of patients. If the patients' VT was uninducible postoperatively with or without the addition of antiarrhythmic therapy, late deaths (3/19) were due to poor myocardial reserve and coronary artery disease, not the reemergence of sustained ventricular arrhythmias during a mean follow-up of 15 months.