PRESENTER DISCLOSURE INFORMATION There are no potential conflicts of interest regarding current presentation
Better synchrony and diastolic function for septal versus apical right ventricular permanent pacing in a 1-year follow-up study R.C. Sisu, A. D. Margulescu, C. Siliste, M. Cinteza, D. Vinereanu University & Emergency Hospital of Bucharest, Romania
RV Apical pacing Background accessible, safe, and stable long-term pacing altered LV contraction 31-53% of patients asymptomatic dyssynchrony higher risk of morbidity and mortality increased risk of heart failure Frohlig et al. P.Clin Electrophysiol 2004; Se and Lau. JACC 2006; McGavigan et al. Curr Opin Cardiol 2006.
Optimal pacing site: theory? RV septal pacing Safe, and stable long-term pacing Shorter fluoroscopic time More physiological activation pathway - shorter QRS duration Possible preservation of LV synchrony Improve outcomes acutely and medium term However: Different lead positions for septal pacing Long-term - no convincing data about its superiority Alexander Kypta et al. Europace 2008; Gabriel V et al. J Interv Card Electrophysiology 2008 Cano O et al. Am J Cardiol 2010.
STUDY AIMS Comparative evaluation of IVS and RVA pacing on cardiac function and synchrony in a long term study - transversal study - TDI measurements of subclinical LV dysfunction Conventional Echocardiography
STUDY GROUP Inclusion criteria: Permanent pacemaker for symptomatic bradycardia Pacing dependent = cum%vp 90% Age > 18 years Written informed consent. Exclusion criteria: Cum%VP < 90% Age > 90 years Recent acute coronary syndrome < 3 months Important medical disability Medical condition with life expectance < 1 year Inappropriate quality of echocardiographic images.
STUDY DESIGN Baseline Visit (11 ± 4 months) 12 months follow-up Visit Conventional echocardiography Structural parameters: LV, LA diameters and volumes, RV, RA diameters Valvular anatomy and function Global systolic function: 2D-EF (Simpson), indexed CO Diastolic function: E/A, E/Vp, E/E ratio Tissue Doppler Imaging - Longitudinal deformation 12 LV segments (basal + mid): septal, lateral, anterior, inferior, posterior, and antero-septal Mean longitudinal peak systolic strain (%), and strain rate (1/s) Time to peak longitudinal systolic strain (TTPS) Vivid7, GE, 3.5 MHz transducer
TDI: longitudinal deformation 12 sites for LSS, SR and TTPS off line measurements
Dyssynchrony Intraventricular dyssynchrony Maximal systolic temporal difference (MAXS) = delay between the shortest and longest of the myocardial timings (TTPS) for all 12 LV segments Standard deviation systolic (SDS) of all 12 LV myocardial timings - measurement of electromechanical delay dispersion Interventricular dyssynchrony Aorto-pulmonary flow delay (APD) = difference between aortic and pulmonary pre-ejection delays using conventional PW Doppler.
Intraventricular dyssynchrony - MAXS -
Results - patients 40 patients (from 60 screened) had baseline study at 11 ± 4 months from pacemaker implantation 20 paced at the apex and 20 at the septal level mean age 74 ± 9 years; 21 male 32 of them performed a follow up visit at 12 months 4 patients were lost to follow up 4 patients died (ALL IN APICAL GROUP; p = 0.036)
Baseline clinical demographic data General information All patients (n=40) Septal pacing (n=20) Apical pacing (n=20) P value Age (mean SD) 74 8 73 9 74 8 n.s. Months post- implantation (mean SD) 11 4 10 4 12 5 n.s. Male, n (%) 21 (52) 8 (40) 13 (65) 0.027 Synus rhythm, n (%) 34 (85) 18 (90) 16 (80) n.s. Atrial fibrillation, n (%) 6 (15) 2 (10) 4 (20) n.s. Pacing modevvi, n (%) DDD, n (%) 21 (52) 8 (38) 13 (62) n.s. 19 (48) 12 (62) 7 (38) n.s Hypertension, n (%) 37 (93) 18 (90) 19 (95) n.s LVH, n (%) 17(43) 8(40) 9(45) n.s. Diabetus mellitus, n (%) 11 (28) 6 (30) 5 (25) n.s. Obesity, n (%) 13 (33) 6 (30) 7 (35) n.s. Prior MI, n (%) 4 (20) 2 (10) 2 (10) n.s. Valvulopathy, n (%) 6(15) 1(5) 5(25) n.s. EF<45%, n (%) 7(17) 5(25) 2(10) n.s. NYHA class (mean SD) 0,5 1 0,3 0.7 0,8 1,2 n.s. Pharmacological therapy ACE inhibitor, n (%) Beta-blocker, n (%) Loop diuretic, n (%) Calcium-blocker, n (%) Spironolactone, n (%) Aspirin, n (%) 29 (73) 15 (75) 14 (70) n.s. 13 (33) 4 (20) 9 (45) n.s. 20 (50) 9 (45) 11 (55) n.s. 15 (38) 7 (35) 8 (40) n.s. 3 (8) 1 (5) 2 (10) n.s. 30(75) 14 (70) 16 (80) n.s.
Standard Echocardiographic Data Pacing sites mean SD Baseline 12 months Septal Apical P Septal Apical P LA mm 40 7 44 8 n.s. 43 7 42 10 n.s. RA mm 38 7 39 6 n.s. 39 10 40 8 n.s. EDLV mm 49 9 47 7 n.s. 48 8 45 9 n.s. ESLV mm 37 9 35 7 n.s. 36 9 35 9 n.s. LVEDV ml 108 33 100 25 n.s. 121 36 106 33 n.s. LVESVml 53 27 47 16 n.s. 64 32 53 19 n.s RVED mm 36 7 36 7 n.s. 32 8* 34 7 n.s. MR grade 1.6 0.7 1.6 1 n.s. 1.8 0.8 1.5 1 n.s. * p=0,032
Apical versus Septal Site at baseline and 12 months follow-up visits * p<0,05 Pacing sites mean SD Baseline 12 months Septal Apical P Septal Apical P LVEF 53 11 54 8 n.s. 49 14 54 8 n.s. CO 2.9 2.2 2.3 1 n.s. 2.6 1 2.2 0.8 n.s. MLSS -11±4-13±5 n.s -12±4-11±3 n.s MLSR -1±0.5-1±0.5 n.s. -1±0.4-1±0.5 n.s. E/A 1.3 1.1 1.5 1 n.s 0.9 0.6 1.9 1.5 0.037 E/Vp 2.5 2.2 2.3 1 n.s. 1.7 0.5 2.1 0.7 0.072 E/E 14 7 17 9 n.s 13 6 18 6 0.04 APD 41 21 40 34 n.s. 41 20 41 25 n.s. SDS 79±32 57±26* n.s 92±49 90±54* n.s MAXS 275±134 195±101* 0.074 280±153 274±122* n.s
MAXS Maximal systolic temporal difference of myocardial timings at baseline and 12 months follow-up visit * P =0.013 300 250 275 * 280 274 200 150 100 50 195 0 Septal baseline Apical baseline Septal 12 months Apical 12 months
SDS 100 90 Standard deviation systolic at baseline and 12 months follow-up * * P =0.022 80 70 60 79 92 90 50 40 30 20 10 57 0 Septal baseline Apical baseline Septal 12 months Apical 12 months
p=0.032 r=0,554
E/A difference between pacing sites at baseline and 12 months follow up visit 6 5 * 4 3 * p<0.05 2 1 E/A baseline 0 E/A 12 months N = 14 14 14 14 RVA IVS Pacing site
Reproducibility Parameter Intraobserver variability LVEF ± 3.4 % CO ± 4.8% LSS ± 4,75% LSR ± 5.5% TTPS ±4.5% Bland-Altman analysis
Factors Needed to Be Considered Co-Morbidities Age VVI/DDD pacing AV Delay Small number Patient Populations Septal position Echocardiographic methodology Confirmation method Location Preexisting Conduction System Disorder
Conclusions Important progression of intraventricular dyssynchrony only for apical site Increased filling pressure and worse diastolic profile only for apical pacing over time. No difference: LVEF, CO, NYHA class longitudinal systolic function, myocardial timings dispersion, inter- or intraventricular dyssynchrony Longer follow-up might reveal more clear differences