group1 (n=7) group 2 (n=10) group 3 (n=31)
p value
Epidemiological background Epidemiological background Epidemiological background Epidemiological background Epidemiological background
Age, years 65 ± 6 71 ± 9 67 ± 11 0.27
Age ≥ 75 years 1 (14) 5 (50) 7 (23) 0.23
Age by first device implantation, years 56 ± 5 66 ± 10 59 ± 11 0.13
Duration from first device implantation to CRT upgrade (days) 3508 (1980-6741) 2136 (1771-3884) 1914 (718-4274) 0.40
Male 1 (14) 6 (60) 21 (68) 0.041
Body mass index (kg/m²) 22 ± 2 23 ± 3 22 ± 4 0.42
Comorbidities Comorbidities Comorbidities Comorbidities Comorbidities
Hypertension 1 (14) 2 (20) 9 (29) 0.7
Diabetes mellitus 0 (0) 3 (30) 8 (26) 0.37
Hyperlipidemia 1 (14) 1 (10) 7 (23) 0.86
Chronic kidney disease 2 (29) 2 (20) 9 (29) 0.9
COPD 0 (0) 0 (0) 0 (0)
Stroke 0 (0) 1 (10) 3 (10) 0.61
High-grade atrio-ventricular block 6 (86) 10 (100) 21 (68) 0.12
Sick sinus syndrome 1 (14) 0 (0) 3 (10) 0.6
Previous frequent RV pacing 6 (86) 10 (100) 26 (84) 0.45
Previous device
PM 5 (71) 10 (100) 23 (74) 0.19
ICD 2(29) 0 (0) 8 (26) 0.19
History of ventricular arrythmias 4 (57) 5 (50) 10 (32) 0.43
Prior VT ablation 1 (14) 3 (30) 2 (6) 0.083
Atrial fibrillation 1 (14) 3 (30) 16 (52) 0.15
Permanent 0 (0) 0 (0) 8 (26) 0.12
HF hospitalization 2 (29) 5 (50) 18 (58) 0.34
NYHA functional class 2 (2-3) 3 (2-3) 3 (3-3.5) 0.06
Coronary Artery Disease 0 (0) 0 (0) 1 (3) 0.76
Valvular heart disease 0 (0) 0 (0) 4 (13) 0.6
Dilated cardiomyopathy 0 (0) 0 (0) 15 (48) 0.0015
Hypertrophic cardiomyopathy 0 (0) 0 (0) 2 (6) 0.56
Medication Medication Medication Medication Medication
β-blocker 6 (86) 9 (90) 26 (84) 0.89
ACEi/ARB 5 (71) 9 (90) 21 (68) 0.4
Spironolactone 4 (57) 6 (60) 19 (61) 0.98
Diuretics 4 (57) 8 (80) 23 (74) 0.64
Amiodarone 2 (29) 3 (30) 5 (16) 0.5
Cardiotonics 1 (14) 1 (10) 4 (13) 0.96
Corticosteroids 7 (100) 6 (60) 0 (0) <0.0001
Dosage before CRT upgrade (mg) 5.0 (2.5-10) 0 (0-0) 0 (0-0) 0.001
Maintenance dosage (mg) 2.5 (2.5-10) 4.1 (0-10) 0 (0-0) 0.037
Electrocardiography Electrocardiography Electrocardiography Electrocardiography Electrocardiography
QRS duration (mm) 173 ± 20 178 ± 21 185 ± 32 0.56
Echocardiographic parameters Echocardiographic parameters Echocardiographic parameters Echocardiographic parameters Echocardiographic parameters
LA-diameter (mm) 40 ± 14 42 ± 4 49 ± 8 0.025
LVEF (%) 27 ± 9 26 ± 7 26.0 ± 7.0 0.98
LVEDV (mL) 168 ± 46 144 ± 46 175 ± 51 0.24
LVESV (mL) 127 ± 44 105 ± 33 127.2 ± 37.4 0.28
MR 3 (2-3) 2 (1.75-3.25) 2 (2-2.5) 0.16
Laboratory data Laboratory data Laboratory data Laboratory data Laboratory data
BNP (pg/mL) 321 (205-767) 271 (102-509) 188 (135-245) 0.7
Creatinine (mg/dL) 0.93 (0.68-1.29) 0.84 (0.79-1.20) 0.73 (0.69-1.28) 0.84
Hemoglobin (mg/dL) 12.4 ± 1.5 12.8 ± 1.6 12.1 ± 2.6 0.7
Type of device Type of device Type of device Type of device Type of device
CRT-P 3 (43) 4 (40) 13 (42) 0.99
CRT-D 4 (57) 6 (60) 18 (58) 0.99