LEFT BUNDLE BRANCH BLOCK- BENIGN OR A HARBINGER OF HEART FAILURE? PROGNOSTIC INDICATOR? Juan Cinca Department and Chair of Cardiology Hospital de la Santa Creu i Sant Pau Universitat Autònoma de Barcelona Barcelona, Spain
DISCLOSURE OF INTEREST No conflicts of interest to be declared
/ PROGNOSTIC INDICATOR? Pathophysiological relationship between & HF I) Primary cause of HF Heart Failure II) Secondary condition aggravating HF Heart Failure
OBJECTIVES Primary pathophysiological potential of Experimental models (healthy hearts) Secondary condition aggravating HF Clinical studies Outcomes in HF cohorts
IN HEALTHY HEARTS LV Circumferential Shortening RV * * * * * LV * * * MRI- Dogs (n=8) Ablation of the LBB ACUTE EFFECTS (%) 0 20 0 20 BASELINE SEPTUM Ejection 0 450ms LATERAL Ejection (RF ablation) SEPTUM Ejection LATERAL Ejection CRHONIC EFFECTS Echocardiographic parameters Baseline 16 Weeks LV Ejection Fraction (%) 43±4 33±6* LV Wall Mass (g) 126±31 145±30* LVED Volume (ml) 104±31 135±53* * p<0.05 LV asynchrony (reduction of cardiac output) LV Remodelling (dysfunction, hypertrophy, and dilation) Vernooy K et al Eur Heart J 2005;26:91-98
IN HEALTHY HEARTS Asynchrony & Intra Myocardial Pressure BASELINE (RV pacing) Dogs (n=17) IMP Tissue Pressure Cathter LAD Flow (Doppler) Shortening of diastolic filling ( stroke volume) Increased septal pressure in diastole (compression of septal vessels) Ono S et al, Circulation 1992;85:1125-1131
SECONDARY EFFECTS IN DISEASED HEARTS Diastolic filling and mitral regurgitation DCM DCM with Doppler MVR duration Doppler MVR duration LV filling LV filling A2 A2 S1 S2 S1 S1 S2 S1 DCM n=40 DCM + n= 12 LV Filling (ms) 325±90 190±45* Mitral Regurgitation (ms) 390±60 495±90* *P<0.01 Xiao HB et al, BrHeartJ 1991;66:443-7
SECONDARY EFFECTS IN DISEASED HEARTS LV Asynchrony Normal subject HF+ Li CH, Pons-Llado et al; Int J Cardiovasc Imaging 2010 LV endocardial displacement Speckle trackying 3D-echo Dispersion of time peaks Healthy n=27) Idiopathic (n=35) EF>50% EF<35% Systolic 4±2 12±2 15±3* Diastolic 1±0.6 2±0.6 5±2* Kang SJ et al; Am J Cardiol 2004;93:1243-1246; *P<0.05 induces systolic and diastolic asynchrony
PATHOPHYSIOLOGICAL POTENTIAL OF is a primary cause of LV remodelling and aggravates LV dysfunction in patiens with heart failure
OBJECTIVES Primary pathophysiological potential of Experimental models (healthy hearts) Secondary condition aggravating HF Clinical studies Outcomes in HF cohorts
1-Year Mortality (%) Italian Network on Congestive Heart Failure 150 cardiology centers, FU:1 year (2000); EP:cardiac death Inclusion: CHF NYHA I-IV; N= 5,517 OUTCOMES OF Clinical profile All-cause Death Sudden Death (n=4,126) Age >70 years (%) 30 31 (n=1,391) Male (%) 88.5 70.7* Dilated CM (%) 31.6 49.3* NYHA III-IV (%) 26.4 32.8* LV EF <30% (%) 30.4 49.2* No * p<0.001 HR: 1.36 (1.14-1.61) P:0.0004 HR: 1.34 (1.05-1.72) P<0.01 is an unfavorable prognostic marker in patients with CHF, independent of age, HF severity, and drug prescriptions Baldasseroni S et al, Am Heart J 2002;143:398-405
OUTCOMES OF Enhanced Feedback For Effective Cardiac Treatment (EFFECT) Ontario hospital records; cardiology nurse abstractors; last March 2006; EP: Mortality (Registered Persons DB); N=9,082 Clinical profile (n=6,951) (n=1,480) Age 75.4±12 76.3±11 Male (%) 47.7 49.8* Previous MI(%) 35.1 41.4* S3 (%) 8.6 12* No echocardiographic data * p<0.001 Survival RBBB Adjusted HR (Age,sex,diabetes,ure,hemoglobin,respiratory Diseae,creatinine,LV fnction) : 1.10 (1.02-1.18), p=0.001 RBBB: 1.10 (0.99-1.21), p=0.08 was independently associated with a higher risk of death and rehospitalization for HF or cardiovascular disease Abdel-Qadir HM et al, Int J Cardiol 2011;146:213-218
Henry Ford Hospital-Intensive Care Unit Data Base Detroit,MI. Period: 1990-1998; EP: Mortality at discharge ICU; FU:Vital status (Death Certificate Registry) 27±28 months OUTCOMES OF Clinical profile Survival (n=2,310) (n=386) Age 63±13 63±14 Male (%) 54 54 Previous MI(%) 32 42* LVEF(%) 40±15 29±15* Renal insufficiency (%) 33 40 Severe MV Regurgitation(%) 6.5 9.3 RBBB * p<0.001 HR (adjusted for age,sex, LVEF,renal dysfunction, prior MI.) RBBB+: 1.17 (1,03-1.31), p=0.01 Left and Right BBB are independently associated with higher all-cause mortality after discharge for severe HF McCullough PA et al, Int J Cardiol 2005;102:303-308
OUTCOMES OF Spanish Network for Heart Failure Research (REDINSCOR) 14 hospitals; Consecutive recruitment at HF Units (prior hospitalization );NYHA II-IV; January 2007-January 2010; FU:21 months (11-33); EP: mortality/readmissions. N=2,254 Pathophysiological Categories LV Necrosis LV Dilation LV Hypertrophy LV LV LV Necrotic Q waves Indexed LVED >32mm/m 2 and LVEF<35% N=567 N=672 N=455 LVH with eccentricity Index >0.38
REDINSCOR REGISTRY Clinical Profile of Pathophysiological Categories 80% 70% Male Necrosis (n=567) Dilation (n=672 Hypertrophy (n=455) RR Interval 800 ms 70% Necrosis (n=567) Dilation (n=672 Hypertrophy (n=455) 60% 50% Body Mass Index 28 Kg/m 2 50% 40% 30% Age 67 yr Atrial Fibrillation /Flutter 30% 10% QRS Complex 118 ms Diabetes Mellitus Arterial Hypertension Left Bundle Branch Block is more frequent in LV dilation category
REDINSCOR REGISTRY Outcomes of the Pathophysiological Categories The LV dilation category had the most unfavorable outcome
REDINSCOR REGISTRY Characteristics of patiens with BBB (n=942 )(59%) Left BBB (n=532) (33%) Right BBB (n=134) (8%) Age (yr) 64.7±13.7 66.8±11.6 67.6±12.6* Male (%) 65 71 75* LVNecrosis (%) 32 16 31** LVDilation (%) 19 49 14** LVHypertrophy(%) 24 13 22** LVEDDiameter (mm) 58±10 65±10 57±10** LVEF (%) 39±16 29±10 39±15** LVMass (g) 348±121 404±123 351±103** MVRegurgitation III-IV (%) 15 27 13** Signs of Right HF (%) 39 42 52** * p<0.005 **p<0.0001 Patients with showed the most evolved LV remodelling pattern Patients with RBBB depict more advanced right HF
REDINSCOR REGISTRY Mortality in BBB All cause mortality Cardiovascular death RBBB p<0.0001 RBBB p<0.0001 HR * : 1.41 (1.10-1.81), p=0.006 RBBB: 1.80 (1.23-2.61),p=0.002 HR * : 1.46 (1.10-1.94), p=0.008 RBBB: 1.81 (1.17-2.80),p=0.007 Adjusted for age, diabetes,arterial hypertension, indexed LV mass, left atrial diameter, hemoglobin, estimated glomerular filtration rate.
REDINSCOR REGISTRY Mortality in BBB Cardiac death Pump failure death RBBB p<0.0001 RBBB p<0.0001 HR : 1.62 (1.20-2.19), p=0.001 RBBB: 1.83 (1.15-2.91),p=0.01 HR : 1.59 (1.12-2.26), p=0.009 RBBB: 2.64 (1.61-4.34),p=0.000 Adjusted for age, diabetes, arterial hypertension, indexed LV mass, left atrial diameter, hemoglobin, glomerular filtration rate., RR interval, mitral valve regurgitation, angiotensin converting enzyme inhibitor treatment
PROGNOSIS OF Heart Failure Survey in Israel (HFSIS) March-April 2003; FU: 4 years (all-cause mortality) (n=1389) RBBB (n=193) (n=306) Age (yr) 71 (62-79) 74 (67-81) 76 (68-81) ** Previous MI (%) 62 67 55* NYHA III-IV (%) 35 45 51** LV EF <30% (%) 29 40 51 ** *p<0.05 * *p<0.001 LVEF <50% LVEF <30% RBBB RBBB RBBB vs : HR 1.29 (1.02-1.64) P=0.035 RBBB vs : HR 1.58 (1.09-2.28) P=0.015 All-cause mortality (no causes of death) RBBB but not is associated with increased long-term mortality in patients with HF, especially in those with advanced LV dysfunction Barsheshet A et al; Am J Cardiol 2011:107:540-544)
CONCLUSIONS Prognostic marker? = YES Left BBB is a primary cause of LV remodelling in healthy hearts (via: septal workload-- dilation-- asymmetrical hypertrophy) The concurrence of Left BBB in patients and HF worsens LV function (via: LV filling-- mitral regurgitation-- LV dilation-- LV asinchrony) Left BBB is a prognostic marker of total and cardiac mortality in patients with HF and is more frequently associated with LV dilation Right BBB emerges as a predictor of unfavorable outcome especially in patients with advanced congestive HF (pump failure death)
PROGNOSIS OF Korean Heart Failure Registry 24 hospitals; Acute HF registry; June 2004-April 2009; EP: Mortality and readmissisons Clinical profile (n=1977) (n=107) RBBB (n=118 Age 67±15 71±12 68±15** Male (%) 50 41 58* NYHA III-IV (%) 69 75 80* LVEF(%) 40±15 29±12 39±13.6** Renal failure (%) 9 3.7 9.3 Rehospitalization and death RBBB PAP in LVEF<40%vs >40%: 52±17.5 vs 40±12.4 mmhg, p=0.01 * p<0.05; ** p<0.001 HR adjusted for age,sex,lvef,creatinine,prior MI, diabetes,.) RBBB vs nobbb: 1.91 (1.37-2.6) p<0.001 RBBB vs : 2.57(1.46-4.5) p=0.001 vs nobbb: 0.75 (0.46-1.2) p=0.2 Right BBB is independently associated with worse outomes in patients with acute HF Hong SJ et al, Int J Cardiol 2012; 157(3):416-8