TC YungPaediatric Cardiology Unit Grantham HospitalHong KongBiventricular pacing in a baby with RV pacing induced heart failureThe 10th South China International Congress of Cardiology, Guangzhou, 2008Male babylAntenatallat 21 week of gestation noted have bradycardia and AV blocklmother anti Ro, RF + ve lLSCS at 35 weeks for progressive fetal heart failure, birth weight 2.36 kglPost-natal lRespiratory distresslCXR : cardiomegaly, CT ratio 67% lPut on nasal CPAP + Isoprenaline infusionCT ratio 67%Transfer to TGH on the day of birth Echo showed normal heart structure, LVSF 38.9%, LVEDD 2.78cm LVEF 77.2% HR 50-60/min, systolic BP 55mmHg while on isoprenaline infusion Epicardial pacemaker insertion the second day after admission RA RV (inferior wall) pacing DDD (90-180/min)Post epicardial DDD pacing: CT ratio 67.9%Measurement at Operation Leads 4965 steroid-eluted leads for both RA and RV Generator-Sensia SE DR 01 DDDR Impedance - V lead 589 - A lead 343 A pacing threshold - 1.8V 0.5ms V pacing threshold - 1.6V 0.5ms R wave8.8mv P wave3.4mvParadoxical septal motion, LVEDD 2.1cm, FS 25.3% , LVEF 58%3 days after RV pacingECHO post DDD pacing:ECHO before DDD pacing:Pericardial effusion Short axis viewLong axis viewDay 12 post pacing Surgical drainage of pericardial fluid (30cc)LVEDD 2.76cm, FS 14.6%, EF 37.8% Dilated LV cavity3 weeks post pacing Discharge from hospital with diuretics Pacing rate 70-180/min3.5 months post RV pacing Significant heart failure symptom: tachypnea and fluid retention Echo - dilated LV, LVEDD 3.3 cm - Moderate tricuspid and mitral incompetence - Poor LV contraction , LVFS 5% LVEF 14.3%- ECG showed irregular rhythm, Wenckebach phenomenon due to rapid atrial rate while on DDD pacing - Pace mode changed to VVI 130/min - Hospitalized for dobutamine infusion ECHOprogressive LV dilatationSevere LV dysynchrony, LVPW Septal delay 255ms3 days after admission When VVI turned off intrinsic escape rhythm, synchronized LV contraction pacing rate to 55/min and started isoprenaline to promote synchronized contraction, But heart failure continued to deteriorate The baby was intubated for 5 days RV pacing rate was increased to 120/minPlan Biventricular epicardial pacing- LV epicardial pacing - LV lead threshold = 1.0 v , 0.4ms - RV/LV delay = 4ms (LV first)1 day after biventricular pacingPost bivent pacingLVPW Septal delay 65msDDD RV pacing LVPW Septal delay 255msSecond day post biventricular pacing LVEDD 3.24cm, LVSF 20.6%, mild mitral incompetenceSecond day post biventricular pacingSense AV intervals VTI of LVOT50ms8.3 80ms9.1 100ms9.1 120ms8.5 140ms5.8V-V delay LV first VTI of LVOT(sense AV 100ms)4 ms7.8 12ms7.5 20ms6.840ms7.5Biventricular pacing QRD duration: 100 ms Post epicardial DDD (RA RV ) pacing 90 -180 ppm QRS duration 120 msDDD RV pacing QRS duration: 120 msBiventricular pacing QRD duration: 100 ms 1 week after Bivent pacingHome with diuretics and ACEI LVEDD 3.19cm, LVSF 20.2% LVEF 49.3% Septal-LVPW delay 65ms 10 days after Bivent pacingLVEDD 3.02cm, LVSF 26.7%, LVEF 60.0% 17 days after Bivent pacingLVEDD 2.51cm, LVSF 27.8% ,LVEF 62.5% 4 weeks post Bivent pacing LVEDD 2.4cm, LVSF 33% LVEF 69.9%3 weeks after Bivent pacing5 months post Bivent pacingLVEDD 2.5cm, LVSF 44% , LVEF 82%no mitral incompetenceOff medication9 months post biventrcular pacingLVEDD 2.32cm, FS 32.5% LVEF 67.2%LV size and LV ejection fractioncmBivent pacingAdmission for heart failureSummary: RV pacing may occasionally induced severe LV dysfunction secondary to LV dysynchrony LV dysfunction may be evident within 2 weeks after RV pacing and progress to dilated cardiomyopathy Biventricular pacing (CRT) can correct the LV dysynchrony and the dilated cardiomyopathy Post epicardial DDD (RA RV ) pacing 90 -180 ppm QRS duration 120 ms5 months post Bivent pacingLVEDD 2.5cm, LVSF 44% , LVEF 82%no mitral incompetenceOff medication