Mild mitral regurgitation reduces exercise capacity in patients with idiopathic dilated cardiomyopathy

The CINCH-FMR postmarket registry: Real-world long-term outcomes with percutaneous mitral valve repair with the Carillon Mitral Contour System®

BACKGROUND

The Carillon® Mitral Contour System® has been studied in 4 prospective controlled studies in the treatment of functional mitral regurgitation (FMR) where it has been found to reduce mitral regurgitation, reduce left ventricular and atrial volumes, and be associated with improvements in clinical parameters.

AIMS

The CINCH post-market registry is designed to evaluate immediate, mid-term and long-term outcomes from a post-approval study of the Carillon® device evaluated in real-world practice.

METHODS

The CINCH post-market registry is a single-arm study of percutaneous mitral annuloplasty with the Carillon device in patients with functional (secondary) mitral regurgitation and symptomatic congestive heart failure when utilized in real-world conditions. Patient selection, echocardiographic hemodynamic measurements, and patient follow-up requirements were performed per standard of care at each institution.

RESULTS

A total of 101 patients treated with the Carillon device at 13 sites in Germany were enrolled in the CINCH registry. The mean age was 75 ± 9 years, 57 % were male, and patient presentation included primarily NYHA class III (69 %) with MR grade 3 (68 %). Over 5 years of follow-up, all-cause mortality was 40.1 %, the incidence of HFH was 53.9 %, and the composite outcome of HFH or death was 66.4 %. At each follow-up interval through 5 years, statistically significant reductions in NYHA class (p < 0.05) and MR grade (p < 0.01) were reported.

CONCLUSIONS

In this "real world" registry of the Carillon Mitral Contour System, procedural safety and medium-term follow-up outcomes is similar to the outcomes seen in the prospective, controlled clinical trials, despite being used in populations of patients that extend outside of those studied in the trials. The use of this therapy in patients with atrial functional mitral regurgitation, and heart failure with preserved ejection fraction, was notable, since these types of patients were excluded from the prospective, controlled trials. This supports possible additional patient populations who might benefit from this type of mechanical therapy. The safety profile of this therapy in this registry and in the earlier trials may support a potential role in earlier forms of secondary mitral regurgitation.

A randomized double-blind trial of an interventional device treatment of functional mitral regurgitation in patients with symptomatic congestive heart failure-Trial design of the REDUCE FMR study

The Carillon Mitral Contour System has been studied in 3 nonrandomized trials in patients with symptomatic congestive heart failure and functional mitral regurgitation. The REDUCE FMR study is a uniquely designed, double-blind trial evaluating the impact of the Carillon device on reducing regurgitant volume, as well as assessing the safety and clinical efficacy of this device. Carillon is a coronary sinus-based indirect annuloplasty device. Eligible patients undergo an invasive venogram to assess coronary sinus vein suitability for the Carillon device. If the venous dimensions are suitable, they are randomized on a 3:1 basis to receive a device or not. Patients and assessors are blinded to the treatment assignment. The primary end point is the difference in regurgitant volume at 1 year between the implanted and nonimplanted groups. Other comparisons include clinical parameters such as heart failure hospitalizations, 6-minute walk test, Kansas City Cardiomyopathy Questionnaire (KCCQ), and other echocardiographic parameters. An exercise echo substudy will also be included.

Coronary Sinus-Based Approach to Mitral Regurgitation

Functional, or secondary, mitral regurgitation (FMR) is clinically important because patient with congestive heart failure with FMR have worse clinical outcomes and associated higher risks than patients without FMR. There is interest in finding repair techniques which may modify the mitral valve dysfunction and reduce the clinical impact. Although several devices have taken advantage of the close anatomical relationship between the coronary sinus and the posterior annulus of the mitral valve, in order to provide a cinching force on the mitral annulus, only the Carillon device is currently in use in humans. A double blind randomized trial is currently being done to evaluate the value of this therapy, building upon the favorable result of three prior safety and efficacy trials, which have led to European approval of the device.

Coronary sinus-based percutaneous annuloplasty as treatment for functional mitral regurgitation: the TITAN II trial

Objective

Functional (or secondary) mitral regurgitation (FMR) is associated with greater morbidity and worse outcomes in patients with congestive heart failure (CHF) and cardiomyopathy. The Carillon® Mitral Contour System® is a coronary sinus-based percutaneous therapy to reduce FMR. We evaluated the safety and efficacy of a modified version of the Carillon device in the treatment of patients with cardiomyopathy and FMR.

Methods

36 patients with CHF, depressed left ventricular function (ejection fraction <40%) and at least moderate FMR underwent the Carillon device implant.

Results

There was 1 major adverse event within 30 days—a death (not device related)—occurring 17 days after the implant. Reductions in FMR and improvements in functional class and 6 min walk tests were seen, similar to prior studies. Device fractures in the high strain region of the proximal anchor (seen in prior studies) were not seen in this study.

Conclusions

The modified Carillon device was associated with improvements in clinical and echocardiographic parameters in treating patients with FMR, while successfully addressing the issue of anchor fracture. This version of the Carillon device will be used in a blinded randomised trial of symptomatic patients with FMR.

Prediction of peak oxygen pulse (O2Ppeak) without exercise testing in older adults

Peak oxygen pulse has been considered a surrogate of cardiovascular function and an independent predictor of all cause mortality. However, O2P(peak) depends on maximal volitional effort which may limit its utility in older subjects. The aim of this study was to develop a model to estimate O2P(peak) without exercise in an elderly sample. This cross-sectional study enrolled 67 community-dwelling older adults (69.4±7.1 years; 41 men) for the non-exercise model development and 30 community-dwelling older adults (67.7±6.4 years; n=30; 17 men) for cross-validation. The non-exercise model was derived through hierarchical regression model and cross-validated by means of PRESS statistics and comparison against an independent sample. Classification accuracy of the model for tertiles of estimated and actual O2P(peak) was tested by gamma (γ) nonparametric correlation. The following prediction equation was generated: -3.416+0.137 × weight (kg)+1.226 × Veterans Specific Activity Questionnaire (VSAQ) (metabolic equivalents, METs)+1.987 × gender (0=women, 1=men)-2.045 × β-Blockers use (0=no, 1=yes)-0.044 × resting heart rate (HR) (R(2)=0.83; standard error of estimate (SEE)=1.68 mL beat(-1)). Correlation in cross-validation group was 0.80 (P<0.001). A high probability was observed for the model to rank the values in the same tertile in validation and cross-validation groups (γ=0.98; γ=0.92, respectively, P<0.05). In conclusion, O2P(peak) can be estimated with reasonable precision without exercise testing, providing an alternative for elder subjects not capable to perform maximal effort.

[Echocardiographic predictors of exercise capacity in patients with heart failure and systolic dysfunction: role of mitral regurgitation]

INTRODUCTION AND OBJECTIVES

Patients with heart failure and similar left ventricular systolic dysfunction have differing exercise capacity. The aim of this study was to identify echocardiographic predictors of exercise capacity in patients with heart failure and systolic dysfunction.

METHODS

We included 150 patients with class II (70%) or III (30%) heart failure with left ventricular ejection fraction below 40%. Six-minute walking test and cardiac color Doppler-echo, including tissue Doppler of mitral and tricuspid rings, were performed. Moderate and severe mitral regurgitation were considered as significant. Two groups were divided according to the median walking distance (290 m): Group 1, <290 m and Group 2, ≥290 m.

RESULTS

Mitral regurgitation was detected in 112 patients (75%), which was significant in 40 (27%). Group 1 showed more significant mitral regurgitation (35 vs 18%), increased left atrium area (27±1 vs 24±1cm(2)), mitral E amplitude (88±5 vs 72±3cm/s) and systolic pulmonary pressure (37±1 vs 32±1mmHg, all P<.05). By logistic regression analysis, only the presence of significant mitral regurgitation was independently associated with less walked distance (odds ratio: 3.44 95% confidence interval 1.02-11.66, P<.05). By multiple linear regression, the only independent predictor of walked distance was left atrium area (r=0.25, beta coefficient: -6.52±2, P<.01).

CONCLUSIONS

In patients with class II-III heart failure and left ventricular systolic dysfunction, the main echocardiographic predictors of exercise capacity are related to the presence of significant mitral regurgitation.

Percutaneous mitral valve interventions: overview of new approaches

The percutaneous management of valvular heart disease has recently been receiving a great deal of interest as an area of great potential. Innovative technologies are now being developed to treat mitral regurgitation. Although there are established surgical techniques for treating organic mitral regurgitation, the surgical management of functional mitral regurgitation remains controversial, and such patients have a poor prognosis. Therefore, a percutaneous treatment for functional mitral regurgitation holds great clinical potential. Having a nonsurgical approach available may be attractive to patients with organic mitral valve regurgitation as well. Several approaches and devices have been designed to treat specifically functional mitral regurgitation, and some of these have been applied to humans in early-stage evaluations. The MitraClip device (Abbott Laboratories, Abbott Park, IL) has been used to treat both functional and degenerative mitral valve regurgitation and has been compared to surgery in the EVEREST II (Endovascular Valve Edge-to-Edge Repair Study II) randomized trial. Although the field of percutaneous management of mitral regurgitation is at an early stage, it has been demonstrated that percutaneous approaches can reduce mitral regurgitation, suggesting there is a great deal of potential for clinical benefit to patients with mitral regurgitation.

Long-term stability of the oxygen pulse curve during maximal exercise

INTRODUCTION

Exercise oxygen pulse (O₂ pulse), a surrogate for stroke volume and arteriovenous oxygen difference, has emerged as an important variable obtained during cardiopulmonary exercise testing.

OBJECTIVES

We hypothesized that the O₂ pulse curve pattern response to a maximal cycling ramp protocol exhibits a stable linear pattern in subjects reevaluated under the same clinical conditions.

METHODS

We retrospectively studied 100 adults (80 males), mean age at baseline of 59 + 12 years, who performed two cardiopulmonary exercise testings (median interval was 15 months), for clinical and/or exercise prescription reasons. The relative O₂ pulse was calculated by dividing its absolute value by body weight. Subjects were classified into quintiles of relative O₂ pulse. Cardiopulmonary exercise testing results and the O₂ pulse curve pattern, expressed by its slope and intercept, were compared among quintiles of relative O₂ pulse at both cardiopulmonary exercise testings.

RESULTS

After excluding the first minute of CPX (rest-exercise transition), the relative O₂ pulse curve exhibited a linear increase, as demonstrated by high coefficients of determination (R² from 0.75 to 0.90; p < 0.05 for all quintiles). Even though maximum oxygen uptake and relative O₂ pulse were significantly higher in the second cardiopulmonary exercise testing for each quintile of relative O₂ pulse (p < 0.05 for all comparisons), no differences were found when slopes and intercepts were compared between the first and second cardiopulmonary exercise testings (p > 0.05 for all comparisons; except for intercept in the 5th quintile).

CONCLUSION

Excluding the rest-exercise transition, the relative O₂ pulse exhibited a stable linear increase throughout maximal exercise in adults that were retested under same clinical conditions.

Mitral regurgitation and cardiac resynchronization therapy

Secondary mitral regurgitation (MR) is frequent in patients with severely depressed left ventricular function. It increases mortality, and decreases exercise capacity. Its main mechanisms are multifactorial, related to apical and outward displacement of the papillary muscles, secondary to an enlarged and a more spherical left ventricle, causing increased subvalvar traction; mitral annular dilatation; and poor contraction of the left ventricle, with a slowed rate of rise of intraventricular pressure and slow closure of the leaflets. Since mechanical dyssynchrony is a major contributor factor to secondary MR, cardiac resynchronization therapy (CRT) could be considered as an alternative therapeutic option for MR, alone or in combination with surgical correction. Effects of CRT on secondary MR are acute and long-term, due to the reverse remodeling of the left ventricle. CRT reduces systolic MR by 30-40%, both at rest and during exercise, and abolishes diastolic MR, by increase of the closing forces and decrease of the tethering forces, acting on the mitral valve; decrease of the mitral annular dilatation represents a minor mechanism. Patients more likely to benefit should have moderate-to-severe MR (but not too severe), of nonischemic etiology, and high interpapillary muscles dyssynchrony. Effects are similar in patients with sinus rhythm and in patients with atrial fibrillation, and in patients with broad and narrow QRS complexes, provided that they have similar extent of dyssynchrony. Biventricular mode is the pacing modality of choice.

Biventricular pacing: impact on exercise-induced increases in mitral insufficiency in patients with chronic heart failure

INTRODUCTION

Mitral regurgitation (MR) in chronic heart failure (CHF) patients frequently worsens with exercise. Cardiac resynchronization therapy (CRT) reduces MR at rest, but its effects on exercise-induced worsening of MR are incompletely explored. The present study examined the influence of CRT on MR during submaximal exercise in CHF patients.

METHODS

Eleven patients with CHF who were treated with CRT underwent echocardiography while performing steady-state exercise during four conduction modes (intrinsic rhythm, right ventricular [RV], biventricular [BiV] and left ventricular [LV] pacing). Measurements of MR were jet area planimetry, effective regurgitant orifice area, peak MR flow rate and regurgitant volume.

RESULTS

At rest and during exercise, there were no differences in dyssynchrony between intrinsic rhythm and RV pacing. BiV and LV pacing reduced dyssynchrony at rest and during exercise compared with intrinsic conduction and RV pacing, and there were no differences in the magnitude of these effects between these two pacing modes. At rest, RV pacing increased MR compared with intrinsic conduction (MR regurgitant volume; P<0.05), whereas BiV and LV pacing reduced MR (reductions in effective regurgitant orifice area and jet area; P<0.02, and MR flow rate; P<0.05 with BiV pacing from intrinsic conduction). MR significantly increased on exercise with intrinsic rhythm and RV pacing, whereas with LV and BiV pacing, there were no significant exercise-induced increases in any MR variable. There were relationships between changes in measures of dyssynchrony and reductions in MR at rest and during exercise.

CONCLUSIONS

CRT reduces MR at rest and during exercise, and prevents exercise-induced MR. Reductions in MR during exercise correlate with improvements in dyssynchrony.

Diagnostic usefulness and prognostic implications of the mitral E/E' ratio in patients with heart failure and severe secondary mitral regurgitation

In patients with chronic heart failure (CHF) and severe secondary mitral regurgitation (MR), the diagnostic usefulness and prognostic impact of tissue Doppler imaging (TDI) is unknown. This prospective study enrolled 370 patients with stable CHF. Severe secondary MR, defined as effective regurgitant orifice area >/=0.20 cm(2), was present in 92 patients (25%). Echo measurements comprised left ventricular volumes, ejection fraction, mitral E/A ratio, deceleration time, and TDI-derived mitral annular velocities (e.g., S', E', A', E/E'). During a follow-up of 790 +/- 450 days, all-cause mortality and rehospitalization data were analyzed. Patients with or without MR did not differ with respect to age or ejection fraction, but patients with MR were in a poorer New York Heart Association functional class and had a higher mitral E/E' ratio. During follow-up, 70 patients (18%) died and 134 patients (36%) were rehospitalized for worsening heart failure. Mortality rate was significantly higher in patients with versus without severe MR (33% vs 14%, p <0.001). In the MR group, the mitral E/E' ratio independently predicted all-cause mortality and was also significantly associated with rehospitalization for worsening heart failure. In patients with MR with an E/E' ratio >13.5, outcome was markedly worse compared with patients with an E/E' ratio </=13.5 (event-free survival rate, 64% vs 31%, p <0.001). In conclusion, in patients with CHF and severe secondary MR, a higher mitral E/E' ratio is associated with increased morbidity and an adverse outcome. TDI appears to be a useful adjunct in the diagnostic workup and risk stratification of such patients.

Role of severe functional mitral regurgitation in predicting electrical remodeling in idiopathic dilated cardiomyopathy

OBJECTIVE

To investigate incidence and predictors of clinically relevant QRS widening (predefined as > or = 10% with respect to baseline) in idiopathic dilated cardiomyopathy (IDC) and particularly the prognostic role of functional mitral regurgitation (MR). Although QRS widening in left ventricular systolic dysfunction carries relevant prognostic and therapeutic implications, its incidence and predictors in patients with IDC remain unknown.

METHODS

We analyzed 114 patients with IDC receiving optimized medical treatment (age 52 +/- 10 years; 44% males; 36% New York Heart Association class III-IV) who underwent clinical, echocardiographic, hemodynamic, and laboratory evaluations and at least two electrocardiograms > or = 6 months after the index evaluation.

RESULTS

During follow-up (median 20 months), 19 (17%) patients developed clinically relevant QRS widening, corresponding to an incidence of 8% per year. At multivariable analysis, the presence of echocardiographically detected severe MR (P = 0.029) and mean right atrial pressure (RAP) by right heart catheterization (P = 0.021) independently predicted clinically relevant QRS widening.

CONCLUSIONS

Clinically relevant QRS widening is relatively frequent in IDC despite optimized medical treatment, and is independently predicted by MR severity and high RAP. IDC patients presenting either of these risk-factors might benefit from strict follow-up, which could also allow timely detection of the onset of indications for cardiac resynchronization therapy.

Quantification of annular dilatation and papillary muscle separation in functional mitral regurgitation: role of anterior mitral leaflet length as reference

BACKGROUND

We hypothesized that anterior mitral leaflet length (ALL) does not differ significantly between normal subjects and patients with functional mitral regurgitation (FMR) and hence may be used as a reference measurement to quantify annular dilatation and papillary muscle separation.

METHODS AND RESULTS

We prospectively studied 50 controls, 15 patients with systolic left ventricular dysfunction (LVD) with significant FMR, and 15 patients with LVD without significant FMR. Significant MR was defined as an effective regurgitant orifice area > or = 0.2 cm2 as measured by the flow convergence method. Annular diameter, interpapillary distance, and ALL were measured, and the following ratios were derived: annular diameter indexed to ALL (ADI) and interpapillary distance indexed to ALL (IPDI). There was no significant difference in ALL among the three groups. The mean ADI was 1.26 times controls in patients with LVD without significant FMR compared to 1.33 times controls in patients with LVD with significant FMR (P = 0.06, no significant difference between groups). The mean IPDI was 1.42 times controls in patients with LVD without significant FMR compared to 2.1 times controls in patients with LVD with significant FMR (P < 0.0001, significant difference between groups).

CONCLUSION

There was no significant difference in ALL between controls and patients with LVD. ALL can be used as a reference measurement to quantify annular dilatation and papillary muscle separation in patients with FMR. Interpapillary distance but not annular diameter indexed to ALL correlates with severity of FMR.

Functional ischemic mitral regurgitation in anterior ventricular remodeling: results of surgical ventricular restoration with and without mitral repair

Ischemic functional mitral regurgitation following ischemic cardiomyopathy is a secondary phenomenon to ventricular dilation, and therapeutic approaches to this complication are not uniform. Solutions to improve mitral function include either mitral repair or observing the effects of coronary revascularization and/or ventricular rebuilding during surgical ventricular restoration (SVR). The present study of 108 patients (comprising 18% of our 588 SVR population) reports the effects of mitral repair following SVR and CABG by comparing geometric, functional, hemodynamic and outcome changes to SVR patients without mitral repair. The degree of mitral regurgitation went from 2.9 +/- 1.2 before to 0.7 +/- 0.7 after SVR and mitral repair. SVR improved EF from 29 +/- 7% to 34 +/- 10% p 0.001; reduced end diastolic volume from 243 +/- 74 to 163 +/- 53 ml and end systolic volume from 170 +/- 63 to 107 +/- 41 ml, p 0.000. Ventricular size and shape geometric measurements improved in all patients, either with and without mitral repair. SVR improved tenting and papillary muscle width between muscle heads in all patients, but alterations in mitral annular size improved only following mitral repair. Preoperative mitral regurgitation occurred in patients with larger ventricular volume and lower ejection fraction and was an independent predictor of operative mortality risk.

Ventricular reverse remodeling and 6-month outcomes in patients receiving cardiac resynchronization therapy: analysis of the MIRACLE study

OBJECTIVE

The objective of this analysis was to determine if there were differences in ventricular reverse remodeling and 6-month outcome with cardiac resynchronization therapy (CRT) among specific subgroups enrolled in the Multicenter InSync Randomized Clinical Evaluation (MIRACLE) Study.

BACKGROUND

Analysis of major subgroups receiving CRT is important in determining who may be most likely to benefit, since all patients who receive CRT do not demonstrate improvement.

METHODS

Differences in response to CRT between subgroups based on baseline echocardiographic parameters, New York Heart Association (NYHA) class, age, gender, beta blocker use, and etiology of heart failure (HF) were analyzed for the clinical end points of the study as well as 6-month HF re-hospitalization or death.

RESULTS

The benefit of CRT over control was similar in all subgroups with respect to all clinical endpoints. However, non-ischemic HF patients had greater improvements with CRT compared to ischemic HF patients in left ventricular end diastolic volume (P < 0.001) and ejection fraction (EF) (6.7% increase vs. 3.2% [P < 0.001]). Greater improvements in EF were also seen in those patients with less severe baseline mitral regurgitation (MR) (P < 0.001). Women but not men receiving CRT were more likely to be event-free from first HF hospitalization or death compared to the control group (Hazard Ratio = 0.157).

CONCLUSIONS

The benefits of CRT with respect to EF and reverse remodeling were greater in patients with non-ischemic HF and less severe MR. Women may also derive more benefit than men with respect to the occurrence of HF hospitalization or death.

Seeing congestive heart failure with the eyes of the mind: a surgical view

Our normal approach is to recognize pathology and deal with what we see. This article shows that surgical actions in patients with congestive heart failure (CHF) are based on secondary changes in apparently normal looking structures that must be altered to restore normal function. These interventions follow the process of opening the normal pericardium to deal with the abnormal heart. Recognition of conceptual changes in structures without obvious pathology will lead to our incising the normal epicardium to deal with the scarred underlying muscle, narrowing the normal annulus to alter tethering of the lengthened papillary muscle chord connections, imbricating dilated normal myocardium between papillary muscle heads to narrow secondary widening, and rebuilding the dilated spheric ventricle to restore a normal elliptic contour. The overall objective is make our mental concepts guide surgical activities, and thus go beyond evident pathology in our corrective efforts. Our intent is to escape the boundary of the visible disease, and aim restoration toward the boundary of normality.

Left ventricular remodeling and functional mitral regurgitation: mechanisms and therapy

Myocardial damage that results in dysfunction and remodeling changes left ventricular shape and size. Mitral competence requires the functional integrity of all components of the mitral apparatus. Progressive remodeling ultimately leads to geometric distortion of multiple elements of the mitral apparatus, resulting in functional mitral regurgitation (MR). In this article, we examine the mechanisms of functional MR in the remodeled ventricle. Surgical treatment should aim to correct all abnormalities of the mitral apparatus. These include (1) revascularization of viable myocardium, (2) reduction of ventricular volume and restoration of shape, (3) realignment of papillary muscles, and (4) reduction of annular orifice size.

Exercise echocardiographic assessment in severe mitral regurgitation

In chronic severe mitral regurgitation, minimum morbidity and mortality is achieved by applying surgical correction before left ventricular dysfunction becomes irreversible. This requires detection of subtle signs of early ventricular decompensation, for which isotonic stress echocardiography is more accurate than is use of resting indices of contractile function alone. We perform serial 6-monthly stress echocardiography for patients with severe mitral regurgitation, and recommend surgery when the exercise end-systolic volume index or ejection fraction reaches the cutoff values in Table 4 or if there is a clear adverse trend. Exercise echocardiography is more accurate than is exercise electrocardiography for detecting concomitant coronary disease prior to revascularization. Stress testing is also an objective measure of symptoms. Color-Doppler stress echocardiography can detect those patients whose mitral regurgitation worsens (or even develops de novo) with exercise, which can explain unexpected symptoms. Stress echocardiography, therefore, provides a comprehensive and cost-effective evaluation of patients with mitral regurgitation that combines functional, diagnostic, and prognostic information.

Clinical and electrophysiologic features of idiopathic left ventricular aneurysm with sustained ventricular tachycardia

We examined 10 patients with idiopathic left ventricular (LV) aneurysm with sustained ventricular tachycardia (VT) (Id-An group), and compared them with those in 16 age- and sex-matched patients who had postinfarction aneurysm and VT (MI-An group) to clarify detailed clinical and electrophysiologic characteristics of idiopathic LV aneurysm. The clinical and laboratory data and results of electrocardiography, electrophysiologic, and morphologic examinations in the two groups were compared. In the Id-An group, the LV aneurysms were located more often at the posterior and/or inferior wall, while in the MI-An group, they were more often located at the anterior and/or apical wall (P<0.001). The LV end-diastolic volume index was significantly smaller and the LV ejection fraction was significantly higher in the Id-An group (P<0.001). The size of the aneurysm and the area with abnormal electrograms in the Id-An group were significantly smaller than those in the MI-An group (P<0.005 and P<0.001, respectively). The inducibility of VT was high in both groups, and ventricular pacing during VT showed entrainment phenomenon in most of the patients. Thus, in both groups, the abnormal electrograms were closely associated with the wall motion abnormality, and reentry was suggested as the mechanism of VT. In the Id-An group, since the lesions were anatomically and electrophysiologically confined to the posterior and/or inferior wall, the global LV function was more well preserved compared with the MI-An group.