***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Background —Intracoronary administration of bone marrow – derived progenitor cells ( BMC ) was shown to improve coronary microvascular function in ischemic heart disease . Because coronary microvascular dysfunction is implicated in the pathogenesis and prognosis of nonischemic dilated cardiomyopathy ( DCM ) , we investigated the effects of intracoronary BMC administration in patients with DCM . Methods and Results —Intracoronary infusion of BMC was performed in 33 patients with DCM by using an over-the-wire balloon catheter . Left ventricular contractility at baseline and after 3 months was assessed by analysis of left ventricular angiograms . Coronary hemodynamics were determined by intracoronary Doppler wire measurements . After 3 months , regional wall motion of the target area ( contractility from −1.08±0.39 to −0.97±0.47 SD/chord , P=0.029 ) and global left ventricular ejection fraction ( from 30.2±10.9 to 33.4±11.5 % , P<0.001 ) were improved . Increase of regional contractile function was directly related to the functionality of the infused cells as measured by their colony-forming capacity . Minimal vascular resistance index was significantly reduced in the BMC -treated vessel after 3 months ( from 1.53±0.63 to 1.32±0.61 mm Hg · s/cm ; P=0.002 , n=24 ) , whereas no changes were observed in the reference vessel ( from 1.60±0.45 to 1.49±0.45 mm Hg · s/cm ; P=0.133 , n=13 ) . Twelve months after BMC infusion , N-terminal prohormone brain natriuretic peptide ( NT-proBNP ) serum levels were decreased , suggesting a beneficial effect on left ventricular remodeling processes ( from 1610±993 to 1473±1147 pg/mL ; P=0.038 for logNT-proBNP , n=26 ) . Conclusions —Intracoronary administration of BMC seems to be associated with improvements in cardiac contractile and microvascular function in patients with DCM . Thus , r and omized blinded studies are warranted to evaluate potential clinical benefits of intracoronary BMC administration in patients with DCM Aims To evaluate the safety profile and efficacy of bone marrow mononuclear cells ( BMMNC ) transplantation for ST-segment elevation myocardial infa rct ion ( STEMI ) by assessing patients and their left ventricular function at up to 4 years follow-up . Methods and results Eighty-six patients with STEMI who had successfully undergone percutaneous coronary intervention ( PCI ) were r and omized to receive intracoronary injection of BMMNC ( n = 41 ) or saline ( n = 45 ) . Left ventricular ejection fraction , as evaluated by UCG , was markedly improved at 6 months ( 0.484 ± 0.5 vs. 0.457 ± 0.6 , P = 0.001 ) , 1 year ( 0.482 ± 0.7 vs. 0.446 ± 0.6 , P < 0.001 ) , and 4 years ( 0.505 ± 0.8 vs. 0.464 ± 0.8 , P < 0.001 ) after BMMNC transplant when compared with control group . However , the current cell therapy did not improve the myocardial viability of the infa rct ed area as assessed by single-photon emission computed tomography analysis at 4 years post-transplant ( 0.263 ± 0.007 in BMMNC group vs. 0.281 ± 0.008 in control group , P = 0.10 ) . During the follow-up period , one control group case ( 2.2 % ) of in-stent restenosis was confirmed by coronary angiography and underwent repeat PCI . Also during follow-up , one death ( 2.2 % ) occurred in the control group , and one patient ( 2.4 % ) in the BMMNC group had transient acute heart failure . Conclusion This study indicates that intracoronary delivery of autologous BMMNC is safe and feasible for STEMI patients who have undergone PCI , and can lead to long-term improvement in myocardial function Rationale : Ixmyelocel-T is associated with a wide range of biological activities relevant to tissue repair and regeneration . Objective : To evaluate the safety and efficacy of ixmyelocel-T in 2 prospect i ve r and omized phase 2A Trials administered via minithoracotomy or intramyocardial catheter injections in patients with dilated cardiomyopathy ( DCM ) stratified by ischemic or nonischemic status . Methods and Results : In IMPACT-DCM , patients were r and omized to either ixmyelocel-T or st and ard-of-care control in a 3:1 ratio ( n=39 ) ;  ixmyelocel-T was administered intramyocardially via minithoracotomy . In Catheter-DCM , patients were r and omized to either ixmyelocel-T or st and ard of care control  in a 2:1 ratio ( n=22 ) ;  ixmyelocel-T was administered intramyocardially using the NOGA Myostar catheter .  Only patients r and omized to ixmyelocel-T underwent bone marrow aspiration and injections . In the 2 studies , a total of 61 patients were r and omized , and 59 were treated or received st and ard of care . Fewer ischemic patients treated with ixmyelocel-T experienced a major adverse cardiovascular event during follow-up when compared with control patients . A similar benefit was not seen in the nonischemic patients . Heart failure exacerbation was the most common major adverse cardiovascular event . Ixmyelocel-T treatment was associated with improved New York Heart Association class , 6-minute walk distance , and Minnesota Living with Heart Failure Question naire scores in the ischemic population relative to control ; a similar trend was not observed in the nonischemic population . Conclusions : Intramyocardial injection with ixmyelocel-T reduces major adverse cardiovascular event and improves symptoms in patients with ischemic DCM but not in patients with nonischemic DCM BACKGROUND AND PURPOSE Although dilated cardiomyopathy ( DCM ) had a poor prognosis in the past , recent studies have shown better survival . However , little is known about the improvement of prognosis in the elderly . This study sought to clarify the changes in prognosis in elderly patients with DCM over the past 20 years . METHODS AND SUBJECTS We studied 54 consecutive patients with DCM ( 38 men and 16 women , aged 65 - 83 years ) who were diagnosed at over 65 years of age . The patients were divided into two groups ( group A : 12 patients diagnosed before 1990 ; group B : 42 patients diagnosed after 1990 ) because after 1990 , based on growing evidence from large-scale , r and omized clinical studies , we intentionally increased the use of angiotensin-converting enzyme inhibitors ( ACEI ) and then beta-blockers at our hospital . RESULTS There were no significant differences in age , gender , NYHA functional class , and the prevalence of atrial fibrillation and ventricular tachycardia between the two groups . Left ventricular ( LV ) size assessed by echocardiography was larger ( LV end-diastolic diameter , 67+/-5.9 versus 62+/-6.6 mm ; p=0.039 ) and LV ejection fraction measured by left ventriculography was lower ( ejection fraction , 24+/-9 versus 35+/-10 % ; p=0.004 ) in group A. ACEI/angiotensin II type 1 receptor blockers ( ARB ) ( 0 % versus 88 % ) or beta-blockers ( 0 % versus 52 % ) were more frequently used in group B.  Antiarrhythmics  ( class Ia or Ib ) ( 75 % versus 14 % ) were less often used in group B. The 5- and 10-year event-free survival rates for cardiac death were 75.4 % and 22.0 % in group A versus 81.2 % and 71.3 % in group B ( log-rank test , p=0.014 ) . CONCLUSIONS The prognosis of DCM patients in the elderly has significantly improved over the past 20 years . The advances in the pharmacologic treatment and earlier diagnosis may have contributed to the better survival Background Cardiac resynchronization therapy using bi-ventricular pacing is proven effective in the management of  heart failure ( HF ) with a wide QRS-complex . In the absence of QRS prolongation , however , device-based resynchronization is reported unsuitable . As an alternative , the present study tests a regenerative cell-based approach in the setting of narrow QRS-complex HF . Methods and Results Progressive cardiac dyssynchrony was provoked in a chronic transgenic model of stress-triggered dilated cardiomyopathy . In contrast to rampant end-stage disease afflicting untreated cohorts , stem cell intervention early in disease , characterized by mechanical dyssynchrony and a narrow QRS-complex , aborted progressive dyssynchronous HF and prevented QRS widening . Stem cell-treated hearts acquired coordinated ventricular contraction and relaxation supporting systolic and diastolic performance . Rescue of contractile dynamics was underpinned by a halted left ventricular dilatation , limited hypertrophy , and reduced fibrosis . Reverse remodeling reflected a restored cardiomyopathic proteome , enforced at systems level through correction of the pathological molecular l and scape and nullified adverse cardiac outcomes . Cell therapy of a dyssynchrony-prone cardiomyopathic cohort translated prospect ively into improved exercise capacity and prolonged survivorship . Conclusions In narrow QRS HF , a regenerative approach demonstrated functional and structural benefit , introducing the prospect of device-autonomous resynchronization therapy for refractory disease AIMS To assess the efficacy and safety of bone marrow cell ( BMC ) therapy after thrombolytic therapy of an acute ST-elevation myocardial infa rct ion ( STEMI ) . METHODS AND RESULTS Patients with STEMI treated with thrombolysis followed by percutaneous coronary intervention ( PCI ) 2 - 6 days after STEMI were r and omly assigned to receive intracoronary BMC s ( n = 40 ) or placebo medium ( n = 40 ) , collected and prepared 3 - 6 h prior PCI and injected into the infa rct artery immediately after stenting .  Efficacy was assessed by the measurement of global left ventricular ejection fraction ( LVEF ) by left ventricular angiography and 2-D echocardiography , and safety by measuring arrhythmia risk variables and restenosis of the stented vessel by intravascular ultrasound . At 6 months , BMC group had a greater absolute increase of global LVEF than placebo group , measured either by angiography ( mean + /- SD increase 7.1 + /- 12.3 vs. 1.2 + /- 11.5 % , P = 0.05 ) or by 2-D echocardiography ( mean + /- SD increase 4.0 + /- 11.2 vs. -1.4 + /- 10.2 % , P = 0.03 ) . No differences were observed between the groups in the adverse clinical events , arrhythmia risk variables , or the minimal lumen diameter of the stented coronary lesion . CONCLUSION Intracoronary BMC therapy is associated with an improvement of global LVEF and neutral effects on arrhythmia risk profile and restenosis of the stented coronary lesions in patients after thrombolytic therapy of STEMI Objective We tested the hypothesis that direct intramyocardial injection of bone marrow mononuclear cells in patients with non-ischemic dilated cardiomyopathy can improve left ventricular function and physical capacity . Methods Thirty non-ischemic dilated cardiomyopathy patients with left ventricular ejection fraction < 35 % were r and omized at a 1:2 ratio into two groups , control and treated . The bone marrow mononuclear cells group received 1.06±108 bone marrow mononuclear cells through mini-thoracotomy . There was no intervention in the control group . Assessment was carried out through clinical evaluations as well as a 6-min walk test , nuclear magnectic resonance imaging and echocardiogram . Results The bone marrow mononuclear cells group showed a trend toward left ventricular ejection fraction improvement , with magnectic resonance imaging - at 3 months , showing an increase from 27.80±6.86 % to 30.13±9.06 % ( P=0.08 ) and returning to baseline at 9 months ( 28.78 % , P=0.77 ) . Magnectic resonance imaging showed no changes in left ventricular ejection fraction during follow-up of the control group ( 28.00±4.32 % , 27.42±7.41 % , and 29.57±4.50 % ) . Echocardiogram showed left ventricular ejection fraction improved in the bone marrow mononuclear cells group at 3 months , 25.09±3.98 to 30.94±9.16 ( P=0.01 ) , and one year 
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Finally , the transplantation of increased numbers of stem cells result ed in no observable additional benefit with respect to LVEF .
Conclusions Bone marrow-derived stem cell therapy might have improved prognoses and appeared to provide moderate benefits in cardiac systolic function at mid-term follow-up .
However , this therapy produced no observed improvement in exercise tolerance