Characteristics of the population according to QRS duration and heart rate
| Variable | QRS <150 ms+ heart rate <70 bpm (n=686) | QRS <150 ms+ heart rate ≥70 bpm (n=900) | QRS ≥150 ms+ heart rate <70 bpm (n=465) | QRS ≥150 ms+ heart rate ≥70 bpm (n=420) | P value |
| Age, median, Q1–Q3 | 72.2 (62.8–80.8) | 74.4 (64.7–82.1) | 70.3 (60.4–78.5) | 70 (61.1–78.6) | <0.0001 |
| Male sex, no (%) | 214 (31.2) | 203 (22.6) | 309 (66.5) | 235 (56.0) | <0.001 |
| Hypertension, no (%) | 269 (39.2) | 282 (31.3) | 190 (40.9) | 157 (37.4) | <0.001 |
| Diabetes, no (%) | 36 (5.2) | 66 (7.3) | 39 (8.4) | 44 (10.5) | 0.01 |
| MI, no (%) | 11 (1.6) | 8 (0.9) | 8 (1.7) | <4 | (0.31) |
| IHD w/o MI, no (%) | 45 (6.6) | 43 (4.8) | 38 (8.2) | 29 (6.9) | 0.08 |
| Malignancy, no (%) | 42 (6.1) | 58 (6.4) | 23 (4.9) | 12 (2.9) | 0.05 |
| PVD, no (%) | 10 (1.5) | 16 (1.8) | 10 (2.2) | 11 (2.6) | 0.55 |
| CVD, no (%) | 29 (4.2) | 34 (3.8) | 23 (4.9) | 18 (4.3) | 0.79 |
| CLD, no (%) | 19 (2.8) | 23 (2.6) | 4 (0.9) | 11 (2.6) | 0.14 |
| Liver disease, no (%) | <4 | <4 | <4 | <4 | 0.54 |
| Renal disease, no (%) | <4 | <4 | <4 | <4 | 0.54 |
| Cardiac glycosides, no (%) | 8 (1.2) | 10 (1.1) | 4 (0.9) | 4 (1.0) | 0.96 |
| ACE inhibitors, no (%) | 137 (20.0) | 83 (9.2) | 101 (21.7) | 48 (11.4) | 0.29 |
| Class II anti-arrythmic | 8 (1.2) | 5 (0.6) | 3 (0.6) | 6 (1.4) | <0.001 |
| AA, no (%) | 8 (1.2) | 5 (0.6) | <4 | 6 (1.4) | 0.33 |
| Outcome (heart failure), no (%) | 36 (5.2) | 52 (5.8) | 30 (6.5) | 24 (5.7) | |
| Outcome (death), no (%) | 72.2 (62.8–80.8) | 74.4 (64.7–82.1) | 70.3 (60.4–78.5) | 70 (61.1–78.6) | <0.001 |
Data show characteristics according to QRS duration and heart rate. Subgroup 1: QRS duration <150 ms and heart rate <70 bpm. Subgroup 2: QRS duration <150 ms and heart rate ≥70 bpm. Subgroup 3: QRS duration ≥150 ms and heart rate <70 bpm. Subgroup 4: QRS duration ≥150 ms and heart rate ≥70 bpm. Categorical variables are presented with numbers and percentages and continuous variables with medians and 25%–75% percentiles (1st–3rd quartiles, Q1–Q3).
AA, aldosterone antagonist; bpm, beats per minute; CLD, chronic lung disease; CVD, cerebrovascular disease; MI, myocardial infarction; IHD w/o MI, ischaemic heart disease without myocardial infarction; PVD, peripheral vascular disease.