... 10 first-degree AV block 13nodal and infranodal partitioning 16prolonged 8, 10 second-degree AV block 14, 15short 193, 202, 247, 250soft first heart sound (S1) and 14Wolff-Parkinson-White ... 2432-hour duration 137, 173, 187, 198, 244, 246, 2493-hour duration 144, 159, 237, 2415-hour duration 171, 178, 243, 2456-hour duration 184, 206, 246, 2509-hour duration 111, 22914-hour ... tachycardia/fibrillation 108 , 228cardioversion, atrial arrhythmias 21chest pain30-minute duration 141, 147, 236, 23845-minute episode 110, 2281-hour episode, previous day 140, 23690-minute duration...