You will be presented with the full text of a biomedical research paper. Please write an abstract for this paper. Your response should include the abstract and no additional text.

Paper text:
incessant ventricular tachycardia ( vt ) occurs infrequently , especially in patients with large post - infarction ventricular aneurysm and severe left ventricular ( lv ) systolic dysfunction.1 , 2 antiarrhythmic drugs are generally ineffective , and the use of an implantable cardioverter / defibrillator ( icd ) is contraindicated;1 management is , therefore , challenging because of the resistance of the arrhythmia to treatment with antiarrhythmic drugs and repeated external cardioversions.1 , 2 incessant vt can also prove life - threatening not only through the arrhythmia per se but also through possible myocardial depression and vasodilatation triggered by the administration of antiarrhythmic drugs in that acute setting.3 as a result , therapeutic options must be aimed at the arrhythmia substrate .
we herein report the case of a patient presenting with incessant vt terminated only by off - pump coronary artery bypass grafting ( cabg ) with aneurysmal plication .
a 59-year - old woman referred to our institute because of incessant wide qrs tachycardia unresponsive to 3 antiarrhythmic drugs . also , repeated synchronized electrical cardioversions were followed by wide qrs tachycardia in a few seconds .
physical examination showed normal blood pressure of 100/70 mmhg , pulse rate of 150 per minute , and respiratory rate of 18 per minute .
lungs were clear , and there was s3 gallop and a systolic murmur at the apex .
she had suffered an anterior myocardial infarction 5 months previously and had been admitted several times in the previous 3 months because of palpitation .
laboratory findings , including cardiac enzymes , were normal ; electrocardiogram showed a wide qrs complex tachycardia indicative of vt ( figure 1 ) ; echocardiography revealed a large apical true aneurysm with severely reduced lv function ( figure 2a ) ; and finally coronary angiography demonstrated significant stenosis in the left anterior descending artery and diagonal arteries .
the patient emergently underwent off - pump cabg with the plication of the aneurysm ( figure 2b ) , upon which sinus rhythm spontaneously emerged and was maintained in the operating room ( figure 3 ) . a single - chamber implantable cardioverter defibrillator ( icd )
was thereafter implanted , and the patient was discharged after one week . at 39 months follow - up without any antiarrhythmic drugs , there was no episode of palpitation , syncope , presyncope , or appropriate therapy by icd .
ventricular tachycardia that repeatedly recurs and persists for more than half of a 24-hour period despite repeated attempts to terminate the arrhythmia is designated 
incessant.3 this type of vt is a therapeutic challenge in that antiarrhythmic agents can cause myocardial depression or vasodilatation , thus aggravating the condition.4 such medications might even facilitate the incessant mechanism itself by slowing cardiac conduction .
use of an icd is also ineffective . indeed , because an icd delivers multiple shocks and does not prevent recurrences , its use is contraindicated as a sole therapeutic option.5 rarely , idiopathic vt that is not associated with structural heart disease is incessant.6 more commonly , incessant vt is due to structural heart disease , with severe , immediate consequences.3 sedation and measures to reduce sympathetic tone are important , and often effective.7 if episodes of arrhythmia are not precipitated by slow heart rates or pauses , the administration of beta - adrenergic blockers should be considered .
intra - aortic balloon counter - pulsation can also be helpful.8 the treatment of choice for incessant tachyarrhythmia is direct intervention to alter the substrate .
catheter ablation is an important option for the management of incessant monomorphic vt and can be life - saving.9 when hemodynamic stability can be maintained , the presence of the tachycardia facilitates mapping to identify the source of the arrhythmia .
most scar - related reentry circuits in patients with prior myocardial infarction are located on the endocardium and are susceptible to catheter ablation from an intravascular , endocardial approach.10 even after successful radiofrequency ablation , the use of an icd is generally advisable because the recurrence of the arrhythmia is a frequent occurrence.11 surgical ablation has also been reported by either subendocardial resection or cryoablation .
sometimes this procedure may be accompanied by aneurysmectomy or endoaneurysmoraphy.12 both percutaneous and surgical ablation approaches are invasive and time - consuming procedures not available in all hospitals , with a moderate success rate even in experienced hands .
the use of an epicardial or subselective transcoronary injection of alcohol is another possible intervention , but it might not be useful in some cases because of anatomic limitations.13 we herein present a patient with incessant vt refractory to antiarrhythmic drugs and electrical cardioversion .
there are reports in the existing literature on the use of aneurysmal plication as a surgical technique for the remodeling of the lv cavity ; to our knowledge , however , there is no report to date on the utilization of this treatment technique to treat the incessant vt . of course , we should not ignore the role of cabg in controlling the ischemia as the triggering factor for initiating the tachycardia .
another explanation for the control of the tachycardia postoperatively in this patient may be simply the time - dependent elimination of the proarrhythmic effect of the prescribed drugs that prominently slow conduction velocity .
be that as it may , the non - recurrence of the arrhythmia at a long - term follow - up is in favor of the causal effect of surgery in changing the electrophysiogical properties of the arrhythmic substrate .
obviously , success is not guaranteed with this intervention modality as is the case with others ; nonetheless , given the life - threatening nature of some cases of incessant vt , we would posit that when percutaneous and surgical ablations are not available and once antiarrhythmic drugs or electrical cardioversion have failed , there may be an opportunity to control the arrhythmia in the operating room after off - pump cabg and plication of the apical aneurysm .
it is also deserving of note that the presence of acute coronary syndrome necessitates coronary revascularization as well .
off - pump left ventricular aneurysmal plication and , if indicated , cabg after selective coronary angiography could be an option when the arrhythmia is refractory to antiarrhythmic drugs and electrical cardioversions and other interventions fail or are not technically available .
there are many treatment modalities available to acutely terminate incessant ventricular tachycardia with variable success rates , but some cases tend to prove refractory to all of them . 
 we report a 59-year - old woman presenting with incessant ventricular tachycardia . 
 echocardiography revealed a large true apical aneurysm and severe left ventricular dysfunction . 
 the arrhythmia was controlled in the operating room after off - pump coronary artery bypass surgery and plication of the apical aneurysm .